NEWS
author wenzelm
Fri, 29 Jun 2012 15:45:50 +0200
changeset 49186 28a6d67c93f0
parent 49135 9fe0e71052a0
child 49220 09c2a3d9aa22
permissions -rw-r--r--
default for \<euro> is now based on eurosym package, instead of slightly exotic babel/greek (which causes problems with the Gentoo installation on lxbroy2);
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Discontinued obsolete method fastsimp / tactic fast_simp_tac, which
    10 is called fastforce / fast_force_tac already since Isabelle2011-1.
    11 
    12 * Updated and extended "isar-ref" manual, reduced remaining material
    13 in old "ref" manual.
    14 
    15 
    16 *** Document preparation ***
    17 
    18 * Default for \<euro> is now based on eurosym package, instead of
    19 slightly exotic babel/greek.
    20 
    21 
    22 *** System ***
    23 
    24 * Discontinued support for Poly/ML 5.2.1, which was the last version
    25 without exception positions and advanced ML compiler/toplevel
    26 configuration.
    27 
    28 
    29 *** HOL ***
    30 
    31 * Simproc for rewriting set comprehensions into pointfree expressions
    32 
    33 * Quickcheck:
    34 
    35   - added an optimisation for equality premises.
    36     It is switched on by default, and can be switched off by setting
    37     the configuration quickcheck_optimise_equality to false.    
    38 
    39 * The SMT solver Z3 has now by default a restricted set of directly
    40 supported features. For the full set of features (div/mod, nonlinear
    41 arithmetic, datatypes/records) with potential proof reconstruction
    42 failures, enable the configuration option "z3_with_extensions".
    43 Minor INCOMPATIBILITY.
    44 
    45 * Sledgehammer:
    46 
    47   - Rationalized type encodings ("type_enc" option).
    48 
    49 
    50 
    51 New in Isabelle2012 (May 2012)
    52 ------------------------------
    53 
    54 *** General ***
    55 
    56 * Prover IDE (PIDE) improvements:
    57 
    58   - more robust Sledgehammer integration (as before the sledgehammer
    59     command-line needs to be typed into the source buffer)
    60   - markup for bound variables
    61   - markup for types of term variables (displayed as tooltips)
    62   - support for user-defined Isar commands within the running session
    63   - improved support for Unicode outside original 16bit range
    64     e.g. glyph for \<A> (thanks to jEdit 4.5.1)
    65 
    66 * Forward declaration of outer syntax keywords within the theory
    67 header -- minor INCOMPATIBILITY for user-defined commands.  Allow new
    68 commands to be used in the same theory where defined.
    69 
    70 * Auxiliary contexts indicate block structure for specifications with
    71 additional parameters and assumptions.  Such unnamed contexts may be
    72 nested within other targets, like 'theory', 'locale', 'class',
    73 'instantiation' etc.  Results from the local context are generalized
    74 accordingly and applied to the enclosing target context.  Example:
    75 
    76   context
    77     fixes x y z :: 'a
    78     assumes xy: "x = y" and yz: "y = z"
    79   begin
    80 
    81   lemma my_trans: "x = z" using xy yz by simp
    82 
    83   end
    84 
    85   thm my_trans
    86 
    87 The most basic application is to factor-out context elements of
    88 several fixes/assumes/shows theorem statements, e.g. see
    89 ~~/src/HOL/Isar_Examples/Group_Context.thy
    90 
    91 Any other local theory specification element works within the "context
    92 ... begin ... end" block as well.
    93 
    94 * Bundled declarations associate attributed fact expressions with a
    95 given name in the context.  These may be later included in other
    96 contexts.  This allows to manage context extensions casually, without
    97 the logical dependencies of locales and locale interpretation.  See
    98 commands 'bundle', 'include', 'including' etc. in the isar-ref manual.
    99 
   100 * Commands 'lemmas' and 'theorems' allow local variables using 'for'
   101 declaration, and results are standardized before being stored.  Thus
   102 old-style "standard" after instantiation or composition of facts
   103 becomes obsolete.  Minor INCOMPATIBILITY, due to potential change of
   104 indices of schematic variables.
   105 
   106 * Rule attributes in local theory declarations (e.g. locale or class)
   107 are now statically evaluated: the resulting theorem is stored instead
   108 of the original expression.  INCOMPATIBILITY in rare situations, where
   109 the historic accident of dynamic re-evaluation in interpretations
   110 etc. was exploited.
   111 
   112 * New tutorial "Programming and Proving in Isabelle/HOL"
   113 ("prog-prove").  It completely supersedes "A Tutorial Introduction to
   114 Structured Isar Proofs" ("isar-overview"), which has been removed.  It
   115 also supersedes "Isabelle/HOL, A Proof Assistant for Higher-Order
   116 Logic" as the recommended beginners tutorial, but does not cover all
   117 of the material of that old tutorial.
   118 
   119 * Updated and extended reference manuals: "isar-ref",
   120 "implementation", "system"; reduced remaining material in old "ref"
   121 manual.
   122 
   123 
   124 *** Pure ***
   125 
   126 * Command 'definition' no longer exports the foundational "raw_def"
   127 into the user context.  Minor INCOMPATIBILITY, may use the regular
   128 "def" result with attribute "abs_def" to imitate the old version.
   129 
   130 * Attribute "abs_def" turns an equation of the form "f x y == t" into
   131 "f == %x y. t", which ensures that "simp" or "unfold" steps always
   132 expand it.  This also works for object-logic equality.  (Formerly
   133 undocumented feature.)
   134 
   135 * Sort constraints are now propagated in simultaneous statements, just
   136 like type constraints.  INCOMPATIBILITY in rare situations, where
   137 distinct sorts used to be assigned accidentally.  For example:
   138 
   139   lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"
   140 
   141   lemma "P (x::'a)" and "Q (y::'a::bar)"
   142     -- "now uniform 'a::bar instead of default sort for first occurrence (!)"
   143 
   144 * Rule composition via attribute "OF" (or ML functions OF/MRS) is more
   145 tolerant against multiple unifiers, as long as the final result is
   146 unique.  (As before, rules are composed in canonical right-to-left
   147 order to accommodate newly introduced premises.)
   148 
   149 * Renamed some inner syntax categories:
   150 
   151     num ~> num_token
   152     xnum ~> xnum_token
   153     xstr ~> str_token
   154 
   155 Minor INCOMPATIBILITY.  Note that in practice "num_const" or
   156 "num_position" etc. are mainly used instead (which also include
   157 position information via constraints).
   158 
   159 * Simplified configuration options for syntax ambiguity: see
   160 "syntax_ambiguity_warning" and "syntax_ambiguity_limit" in isar-ref
   161 manual.  Minor INCOMPATIBILITY.
   162 
   163 * Discontinued configuration option "syntax_positions": atomic terms
   164 in parse trees are always annotated by position constraints.
   165 
   166 * Old code generator for SML and its commands 'code_module',
   167 'code_library', 'consts_code', 'types_code' have been discontinued.
   168 Use commands of the generic code generator instead.  INCOMPATIBILITY.
   169 
   170 * Redundant attribute "code_inline" has been discontinued. Use
   171 "code_unfold" instead.  INCOMPATIBILITY.
   172 
   173 * Dropped attribute "code_unfold_post" in favor of the its dual
   174 "code_abbrev", which yields a common pattern in definitions like
   175 
   176   definition [code_abbrev]: "f = t"
   177 
   178 INCOMPATIBILITY.
   179 
   180 * Obsolete 'types' command has been discontinued.  Use 'type_synonym'
   181 instead.  INCOMPATIBILITY.
   182 
   183 * Discontinued old "prems" fact, which used to refer to the accidental
   184 collection of foundational premises in the context (already marked as
   185 legacy since Isabelle2011).
   186 
   187 
   188 *** HOL ***
   189 
   190 * Type 'a set is now a proper type constructor (just as before
   191 Isabelle2008).  Definitions mem_def and Collect_def have disappeared.
   192 Non-trivial INCOMPATIBILITY.  For developments keeping predicates and
   193 sets separate, it is often sufficient to rephrase some set S that has
   194 been accidentally used as predicates by "%x. x : S", and some
   195 predicate P that has been accidentally used as set by "{x. P x}".
   196 Corresponding proofs in a first step should be pruned from any
   197 tinkering with former theorems mem_def and Collect_def as far as
   198 possible.
   199 
   200 For developments which deliberately mix predicates and sets, a
   201 planning step is necessary to determine what should become a predicate
   202 and what a set.  It can be helpful to carry out that step in
   203 Isabelle2011-1 before jumping right into the current release.
   204 
   205 * Code generation by default implements sets as container type rather
   206 than predicates.  INCOMPATIBILITY.
   207 
   208 * New type synonym 'a rel = ('a * 'a) set
   209 
   210 * The representation of numerals has changed.  Datatype "num"
   211 represents strictly positive binary numerals, along with functions
   212 "numeral :: num => 'a" and "neg_numeral :: num => 'a" to represent
   213 positive and negated numeric literals, respectively.  See also
   214 definitions in ~~/src/HOL/Num.thy.  Potential INCOMPATIBILITY, some
   215 user theories may require adaptations as follows:
   216 
   217   - Theorems with number_ring or number_semiring constraints: These
   218     classes are gone; use comm_ring_1 or comm_semiring_1 instead.
   219 
   220   - Theories defining numeric types: Remove number, number_semiring,
   221     and number_ring instances. Defer all theorems about numerals until
   222     after classes one and semigroup_add have been instantiated.
   223 
   224   - Numeral-only simp rules: Replace each rule having a "number_of v"
   225     pattern with two copies, one for numeral and one for neg_numeral.
   226 
   227   - Theorems about subclasses of semiring_1 or ring_1: These classes
   228     automatically support numerals now, so more simp rules and
   229     simprocs may now apply within the proof.
   230 
   231   - Definitions and theorems using old constructors Pls/Min/Bit0/Bit1:
   232     Redefine using other integer operations.
   233 
   234 * Transfer: New package intended to generalize the existing
   235 "descending" method and related theorem attributes from the Quotient
   236 package.  (Not all functionality is implemented yet, but future
   237 development will focus on Transfer as an eventual replacement for the
   238 corresponding parts of the Quotient package.)
   239 
   240   - transfer_rule attribute: Maintains a collection of transfer rules,
   241     which relate constants at two different types. Transfer rules may
   242     relate different type instances of the same polymorphic constant,
   243     or they may relate an operation on a raw type to a corresponding
   244     operation on an abstract type (quotient or subtype). For example:
   245 
   246     ((A ===> B) ===> list_all2 A ===> list_all2 B) map map
   247     (cr_int ===> cr_int ===> cr_int) (%(x,y) (u,v). (x+u, y+v)) plus_int
   248 
   249   - transfer method: Replaces a subgoal on abstract types with an
   250     equivalent subgoal on the corresponding raw types. Constants are
   251     replaced with corresponding ones according to the transfer rules.
   252     Goals are generalized over all free variables by default; this is
   253     necessary for variables whose types change, but can be overridden
   254     for specific variables with e.g. "transfer fixing: x y z".  The
   255     variant transfer' method allows replacing a subgoal with one that
   256     is logically stronger (rather than equivalent).
   257 
   258   - relator_eq attribute: Collects identity laws for relators of
   259     various type constructors, e.g. "list_all2 (op =) = (op =)".  The
   260     transfer method uses these lemmas to infer transfer rules for
   261     non-polymorphic constants on the fly.
   262 
   263   - transfer_prover method: Assists with proving a transfer rule for a
   264     new constant, provided the constant is defined in terms of other
   265     constants that already have transfer rules. It should be applied
   266     after unfolding the constant definitions.
   267 
   268   - HOL/ex/Transfer_Int_Nat.thy: Example theory demonstrating transfer
   269     from type nat to type int.
   270 
   271 * Lifting: New package intended to generalize the quotient_definition
   272 facility of the Quotient package; designed to work with Transfer.
   273 
   274   - lift_definition command: Defines operations on an abstract type in
   275     terms of a corresponding operation on a representation
   276     type.  Example syntax:
   277 
   278     lift_definition dlist_insert :: "'a => 'a dlist => 'a dlist"
   279       is List.insert
   280 
   281     Users must discharge a respectfulness proof obligation when each
   282     constant is defined. (For a type copy, i.e. a typedef with UNIV,
   283     the proof is discharged automatically.) The obligation is
   284     presented in a user-friendly, readable form; a respectfulness
   285     theorem in the standard format and a transfer rule are generated
   286     by the package.
   287 
   288   - Integration with code_abstype: For typedefs (e.g. subtypes
   289     corresponding to a datatype invariant, such as dlist),
   290     lift_definition generates a code certificate theorem and sets up
   291     code generation for each constant.
   292 
   293   - setup_lifting command: Sets up the Lifting package to work with a
   294     user-defined type. The user must provide either a quotient theorem
   295     or a type_definition theorem.  The package configures transfer
   296     rules for equality and quantifiers on the type, and sets up the
   297     lift_definition command to work with the type.
   298 
   299   - Usage examples: See Quotient_Examples/Lift_DList.thy,
   300     Quotient_Examples/Lift_RBT.thy, Quotient_Examples/Lift_FSet.thy,
   301     Word/Word.thy and Library/Float.thy.
   302 
   303 * Quotient package:
   304 
   305   - The 'quotient_type' command now supports a 'morphisms' option with
   306     rep and abs functions, similar to typedef.
   307 
   308   - 'quotient_type' sets up new types to work with the Lifting and
   309     Transfer packages, as with 'setup_lifting'.
   310 
   311   - The 'quotient_definition' command now requires the user to prove a
   312     respectfulness property at the point where the constant is
   313     defined, similar to lift_definition; INCOMPATIBILITY.
   314 
   315   - Renamed predicate 'Quotient' to 'Quotient3', and renamed theorems
   316     accordingly, INCOMPATIBILITY.
   317 
   318 * New diagnostic command 'find_unused_assms' to find potentially
   319 superfluous assumptions in theorems using Quickcheck.
   320 
   321 * Quickcheck:
   322 
   323   - Quickcheck returns variable assignments as counterexamples, which
   324     allows to reveal the underspecification of functions under test.
   325     For example, refuting "hd xs = x", it presents the variable
   326     assignment xs = [] and x = a1 as a counterexample, assuming that
   327     any property is false whenever "hd []" occurs in it.
   328 
   329     These counterexample are marked as potentially spurious, as
   330     Quickcheck also returns "xs = []" as a counterexample to the
   331     obvious theorem "hd xs = hd xs".
   332 
   333     After finding a potentially spurious counterexample, Quickcheck
   334     continues searching for genuine ones.
   335 
   336     By default, Quickcheck shows potentially spurious and genuine
   337     counterexamples. The option "genuine_only" sets quickcheck to only
   338     show genuine counterexamples.
   339 
   340   - The command 'quickcheck_generator' creates random and exhaustive
   341     value generators for a given type and operations.
   342 
   343     It generates values by using the operations as if they were
   344     constructors of that type.
   345 
   346   - Support for multisets.
   347 
   348   - Added "use_subtype" options.
   349 
   350   - Added "quickcheck_locale" configuration to specify how to process
   351     conjectures in a locale context.
   352 
   353 * Nitpick: Fixed infinite loop caused by the 'peephole_optim' option
   354 and affecting 'rat' and 'real'.
   355 
   356 * Sledgehammer:
   357   - Integrated more tightly with SPASS, as described in the ITP 2012
   358     paper "More SPASS with Isabelle".
   359   - Made it try "smt" as a fallback if "metis" fails or times out.
   360   - Added support for the following provers: Alt-Ergo (via Why3 and
   361     TFF1), iProver, iProver-Eq.
   362   - Replaced remote E-SInE with remote Satallax in the default setup.
   363   - Sped up the minimizer.
   364   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   365   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   366   - Renamed "sound" option to "strict".
   367 
   368 * Metis: Added possibility to specify lambda translations scheme as a
   369 parenthesized argument (e.g., "by (metis (lifting) ...)").
   370 
   371 * SMT: Renamed "smt_fixed" option to "smt_read_only_certificates".
   372 
   373 * Command 'try0': Renamed from 'try_methods'. INCOMPATIBILITY.
   374 
   375 * New "case_product" attribute to generate a case rule doing multiple
   376 case distinctions at the same time.  E.g.
   377 
   378   list.exhaust [case_product nat.exhaust]
   379 
   380 produces a rule which can be used to perform case distinction on both
   381 a list and a nat.
   382 
   383 * New "eventually_elim" method as a generalized variant of the
   384 eventually_elim* rules.  Supports structured proofs.
   385 
   386 * Typedef with implicit set definition is considered legacy.  Use
   387 "typedef (open)" form instead, which will eventually become the
   388 default.
   389 
   390 * Record: code generation can be switched off manually with
   391 
   392   declare [[record_coden = false]]  -- "default true"
   393 
   394 * Datatype: type parameters allow explicit sort constraints.
   395 
   396 * Concrete syntax for case expressions includes constraints for source
   397 positions, and thus produces Prover IDE markup for its bindings.
   398 INCOMPATIBILITY for old-style syntax translations that augment the
   399 pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of
   400 one_case.
   401 
   402 * Clarified attribute "mono_set": pure declaration without modifying
   403 the result of the fact expression.
   404 
   405 * More default pred/set conversions on a couple of relation operations
   406 and predicates.  Added powers of predicate relations.  Consolidation
   407 of some relation theorems:
   408 
   409   converse_def ~> converse_unfold
   410   rel_comp_def ~> relcomp_unfold
   411   symp_def ~> (modified, use symp_def and sym_def instead)
   412   transp_def ~> transp_trans
   413   Domain_def ~> Domain_unfold
   414   Range_def ~> Domain_converse [symmetric]
   415 
   416 Generalized theorems INF_INT_eq, INF_INT_eq2, SUP_UN_eq, SUP_UN_eq2.
   417 
   418 See theory "Relation" for examples for making use of pred/set
   419 conversions by means of attributes "to_set" and "to_pred".
   420 
   421 INCOMPATIBILITY.
   422 
   423 * Renamed facts about the power operation on relations, i.e., relpow
   424 to match the constant's name:
   425 
   426   rel_pow_1 ~> relpow_1
   427   rel_pow_0_I ~> relpow_0_I
   428   rel_pow_Suc_I ~> relpow_Suc_I
   429   rel_pow_Suc_I2 ~> relpow_Suc_I2
   430   rel_pow_0_E ~> relpow_0_E
   431   rel_pow_Suc_E ~> relpow_Suc_E
   432   rel_pow_E ~> relpow_E
   433   rel_pow_Suc_D2 ~> relpow_Suc_D2
   434   rel_pow_Suc_E2 ~> relpow_Suc_E2
   435   rel_pow_Suc_D2' ~> relpow_Suc_D2'
   436   rel_pow_E2 ~> relpow_E2
   437   rel_pow_add ~> relpow_add
   438   rel_pow_commute ~> relpow
   439   rel_pow_empty ~> relpow_empty:
   440   rtrancl_imp_UN_rel_pow ~> rtrancl_imp_UN_relpow
   441   rel_pow_imp_rtrancl ~> relpow_imp_rtrancl
   442   rtrancl_is_UN_rel_pow ~> rtrancl_is_UN_relpow
   443   rtrancl_imp_rel_pow ~> rtrancl_imp_relpow
   444   rel_pow_fun_conv ~> relpow_fun_conv
   445   rel_pow_finite_bounded1 ~> relpow_finite_bounded1
   446   rel_pow_finite_bounded ~> relpow_finite_bounded
   447   rtrancl_finite_eq_rel_pow ~> rtrancl_finite_eq_relpow
   448   trancl_finite_eq_rel_pow ~> trancl_finite_eq_relpow
   449   single_valued_rel_pow ~> single_valued_relpow
   450 
   451 INCOMPATIBILITY.
   452 
   453 * Theory Relation: Consolidated constant name for relation composition
   454 and corresponding theorem names:
   455 
   456   - Renamed constant rel_comp to relcomp.
   457 
   458   - Dropped abbreviation pred_comp. Use relcompp instead.
   459 
   460   - Renamed theorems:
   461 
   462     rel_compI ~> relcompI
   463     rel_compEpair ~> relcompEpair
   464     rel_compE ~> relcompE
   465     pred_comp_rel_comp_eq ~> relcompp_relcomp_eq
   466     rel_comp_empty1 ~> relcomp_empty1
   467     rel_comp_mono ~> relcomp_mono
   468     rel_comp_subset_Sigma ~> relcomp_subset_Sigma
   469     rel_comp_distrib ~> relcomp_distrib
   470     rel_comp_distrib2 ~> relcomp_distrib2
   471     rel_comp_UNION_distrib ~> relcomp_UNION_distrib
   472     rel_comp_UNION_distrib2 ~> relcomp_UNION_distrib2
   473     single_valued_rel_comp ~> single_valued_relcomp
   474     rel_comp_def ~> relcomp_unfold
   475     converse_rel_comp ~> converse_relcomp
   476     pred_compI ~> relcomppI
   477     pred_compE ~> relcomppE
   478     pred_comp_bot1 ~> relcompp_bot1
   479     pred_comp_bot2 ~> relcompp_bot2
   480     transp_pred_comp_less_eq ~> transp_relcompp_less_eq
   481     pred_comp_mono ~> relcompp_mono
   482     pred_comp_distrib ~> relcompp_distrib
   483     pred_comp_distrib2 ~> relcompp_distrib2
   484     converse_pred_comp ~> converse_relcompp
   485 
   486     finite_rel_comp ~> finite_relcomp
   487 
   488     set_rel_comp ~> set_relcomp
   489 
   490 INCOMPATIBILITY.
   491 
   492 * Theory Divides: Discontinued redundant theorems about div and mod.
   493 INCOMPATIBILITY, use the corresponding generic theorems instead.
   494 
   495   DIVISION_BY_ZERO ~> div_by_0, mod_by_0
   496   zdiv_self ~> div_self
   497   zmod_self ~> mod_self
   498   zdiv_zero ~> div_0
   499   zmod_zero ~> mod_0
   500   zdiv_zmod_equality ~> div_mod_equality2
   501   zdiv_zmod_equality2 ~> div_mod_equality
   502   zmod_zdiv_trivial ~> mod_div_trivial
   503   zdiv_zminus_zminus ~> div_minus_minus
   504   zmod_zminus_zminus ~> mod_minus_minus
   505   zdiv_zminus2 ~> div_minus_right
   506   zmod_zminus2 ~> mod_minus_right
   507   zdiv_minus1_right ~> div_minus1_right
   508   zmod_minus1_right ~> mod_minus1_right
   509   zdvd_mult_div_cancel ~> dvd_mult_div_cancel
   510   zmod_zmult1_eq ~> mod_mult_right_eq
   511   zpower_zmod ~> power_mod
   512   zdvd_zmod ~> dvd_mod
   513   zdvd_zmod_imp_zdvd ~> dvd_mod_imp_dvd
   514   mod_mult_distrib ~> mult_mod_left
   515   mod_mult_distrib2 ~> mult_mod_right
   516 
   517 * Removed redundant theorems nat_mult_2 and nat_mult_2_right; use
   518 generic mult_2 and mult_2_right instead. INCOMPATIBILITY.
   519 
   520 * Finite_Set.fold now qualified.  INCOMPATIBILITY.
   521 
   522 * Consolidated theorem names concerning fold combinators:
   523 
   524   inf_INFI_fold_inf ~> inf_INF_fold_inf
   525   sup_SUPR_fold_sup ~> sup_SUP_fold_sup
   526   INFI_fold_inf ~> INF_fold_inf
   527   SUPR_fold_sup ~> SUP_fold_sup
   528   union_set ~> union_set_fold
   529   minus_set ~> minus_set_fold
   530   INFI_set_fold ~> INF_set_fold
   531   SUPR_set_fold ~> SUP_set_fold
   532   INF_code ~> INF_set_foldr
   533   SUP_code ~> SUP_set_foldr
   534   foldr.simps ~> foldr.simps (in point-free formulation)
   535   foldr_fold_rev ~> foldr_conv_fold
   536   foldl_fold ~> foldl_conv_fold
   537   foldr_foldr ~> foldr_conv_foldl
   538   foldl_foldr ~> foldl_conv_foldr
   539   fold_set_remdups ~> fold_set_fold_remdups
   540   fold_set ~> fold_set_fold
   541   fold1_set ~> fold1_set_fold
   542 
   543 INCOMPATIBILITY.
   544 
   545 * Dropped rarely useful theorems concerning fold combinators:
   546 foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
   547 rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
   548 concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
   549 foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
   550 listsum_conv_fold, listsum_foldl, sort_foldl_insort, foldl_assoc,
   551 foldr_conv_foldl, start_le_sum, elem_le_sum, sum_eq_0_conv.
   552 INCOMPATIBILITY.  For the common phrases "%xs. List.foldr plus xs 0"
   553 and "List.foldl plus 0", prefer "List.listsum".  Otherwise it can be
   554 useful to boil down "List.foldr" and "List.foldl" to "List.fold" by
   555 unfolding "foldr_conv_fold" and "foldl_conv_fold".
   556 
   557 * Dropped lemmas minus_set_foldr, union_set_foldr, union_coset_foldr,
   558 inter_coset_foldr, Inf_fin_set_foldr, Sup_fin_set_foldr,
   559 Min_fin_set_foldr, Max_fin_set_foldr, Inf_set_foldr, Sup_set_foldr,
   560 INF_set_foldr, SUP_set_foldr.  INCOMPATIBILITY.  Prefer corresponding
   561 lemmas over fold rather than foldr, or make use of lemmas
   562 fold_conv_foldr and fold_rev.
   563 
   564 * Congruence rules Option.map_cong and Option.bind_cong for recursion
   565 through option types.
   566 
   567 * "Transitive_Closure.ntrancl": bounded transitive closure on
   568 relations.
   569 
   570 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
   571 
   572 * Theory Int: Discontinued many legacy theorems specific to type int.
   573 INCOMPATIBILITY, use the corresponding generic theorems instead.
   574 
   575   zminus_zminus ~> minus_minus
   576   zminus_0 ~> minus_zero
   577   zminus_zadd_distrib ~> minus_add_distrib
   578   zadd_commute ~> add_commute
   579   zadd_assoc ~> add_assoc
   580   zadd_left_commute ~> add_left_commute
   581   zadd_ac ~> add_ac
   582   zmult_ac ~> mult_ac
   583   zadd_0 ~> add_0_left
   584   zadd_0_right ~> add_0_right
   585   zadd_zminus_inverse2 ~> left_minus
   586   zmult_zminus ~> mult_minus_left
   587   zmult_commute ~> mult_commute
   588   zmult_assoc ~> mult_assoc
   589   zadd_zmult_distrib ~> left_distrib
   590   zadd_zmult_distrib2 ~> right_distrib
   591   zdiff_zmult_distrib ~> left_diff_distrib
   592   zdiff_zmult_distrib2 ~> right_diff_distrib
   593   zmult_1 ~> mult_1_left
   594   zmult_1_right ~> mult_1_right
   595   zle_refl ~> order_refl
   596   zle_trans ~> order_trans
   597   zle_antisym ~> order_antisym
   598   zle_linear ~> linorder_linear
   599   zless_linear ~> linorder_less_linear
   600   zadd_left_mono ~> add_left_mono
   601   zadd_strict_right_mono ~> add_strict_right_mono
   602   zadd_zless_mono ~> add_less_le_mono
   603   int_0_less_1 ~> zero_less_one
   604   int_0_neq_1 ~> zero_neq_one
   605   zless_le ~> less_le
   606   zpower_zadd_distrib ~> power_add
   607   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   608   zero_le_zpower_abs ~> zero_le_power_abs
   609 
   610 * Theory Deriv: Renamed
   611 
   612   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   613 
   614 * Theory Library/Multiset: Improved code generation of multisets.
   615 
   616 * Theory HOL/Library/Set_Algebras: Addition and multiplication on sets
   617 are expressed via type classes again. The special syntax
   618 \<oplus>/\<otimes> has been replaced by plain +/*. Removed constant
   619 setsum_set, which is now subsumed by Big_Operators.setsum.
   620 INCOMPATIBILITY.
   621 
   622 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
   623 use theory HOL/Library/Nat_Bijection instead.
   624 
   625 * Theory HOL/Library/RBT_Impl: Backing implementation of red-black
   626 trees is now inside a type class context.  Names of affected
   627 operations and lemmas have been prefixed by rbt_.  INCOMPATIBILITY for
   628 theories working directly with raw red-black trees, adapt the names as
   629 follows:
   630 
   631   Operations:
   632   bulkload -> rbt_bulkload
   633   del_from_left -> rbt_del_from_left
   634   del_from_right -> rbt_del_from_right
   635   del -> rbt_del
   636   delete -> rbt_delete
   637   ins -> rbt_ins
   638   insert -> rbt_insert
   639   insertw -> rbt_insert_with
   640   insert_with_key -> rbt_insert_with_key
   641   map_entry -> rbt_map_entry
   642   lookup -> rbt_lookup
   643   sorted -> rbt_sorted
   644   tree_greater -> rbt_greater
   645   tree_less -> rbt_less
   646   tree_less_symbol -> rbt_less_symbol
   647   union -> rbt_union
   648   union_with -> rbt_union_with
   649   union_with_key -> rbt_union_with_key
   650 
   651   Lemmas:
   652   balance_left_sorted -> balance_left_rbt_sorted
   653   balance_left_tree_greater -> balance_left_rbt_greater
   654   balance_left_tree_less -> balance_left_rbt_less
   655   balance_right_sorted -> balance_right_rbt_sorted
   656   balance_right_tree_greater -> balance_right_rbt_greater
   657   balance_right_tree_less -> balance_right_rbt_less
   658   balance_sorted -> balance_rbt_sorted
   659   balance_tree_greater -> balance_rbt_greater
   660   balance_tree_less -> balance_rbt_less
   661   bulkload_is_rbt -> rbt_bulkload_is_rbt
   662   combine_sorted -> combine_rbt_sorted
   663   combine_tree_greater -> combine_rbt_greater
   664   combine_tree_less -> combine_rbt_less
   665   delete_in_tree -> rbt_delete_in_tree
   666   delete_is_rbt -> rbt_delete_is_rbt
   667   del_from_left_tree_greater -> rbt_del_from_left_rbt_greater
   668   del_from_left_tree_less -> rbt_del_from_left_rbt_less
   669   del_from_right_tree_greater -> rbt_del_from_right_rbt_greater
   670   del_from_right_tree_less -> rbt_del_from_right_rbt_less
   671   del_in_tree -> rbt_del_in_tree
   672   del_inv1_inv2 -> rbt_del_inv1_inv2
   673   del_sorted -> rbt_del_rbt_sorted
   674   del_tree_greater -> rbt_del_rbt_greater
   675   del_tree_less -> rbt_del_rbt_less
   676   dom_lookup_Branch -> dom_rbt_lookup_Branch
   677   entries_lookup -> entries_rbt_lookup
   678   finite_dom_lookup -> finite_dom_rbt_lookup
   679   insert_sorted -> rbt_insert_rbt_sorted
   680   insertw_is_rbt -> rbt_insertw_is_rbt
   681   insertwk_is_rbt -> rbt_insertwk_is_rbt
   682   insertwk_sorted -> rbt_insertwk_rbt_sorted
   683   insertw_sorted -> rbt_insertw_rbt_sorted
   684   ins_sorted -> ins_rbt_sorted
   685   ins_tree_greater -> ins_rbt_greater
   686   ins_tree_less -> ins_rbt_less
   687   is_rbt_sorted -> is_rbt_rbt_sorted
   688   lookup_balance -> rbt_lookup_balance
   689   lookup_bulkload -> rbt_lookup_rbt_bulkload
   690   lookup_delete -> rbt_lookup_rbt_delete
   691   lookup_Empty -> rbt_lookup_Empty
   692   lookup_from_in_tree -> rbt_lookup_from_in_tree
   693   lookup_in_tree -> rbt_lookup_in_tree
   694   lookup_ins -> rbt_lookup_ins
   695   lookup_insert -> rbt_lookup_rbt_insert
   696   lookup_insertw -> rbt_lookup_rbt_insertw
   697   lookup_insertwk -> rbt_lookup_rbt_insertwk
   698   lookup_keys -> rbt_lookup_keys
   699   lookup_map -> rbt_lookup_map
   700   lookup_map_entry -> rbt_lookup_rbt_map_entry
   701   lookup_tree_greater -> rbt_lookup_rbt_greater
   702   lookup_tree_less -> rbt_lookup_rbt_less
   703   lookup_union -> rbt_lookup_rbt_union
   704   map_entry_color_of -> rbt_map_entry_color_of
   705   map_entry_inv1 -> rbt_map_entry_inv1
   706   map_entry_inv2 -> rbt_map_entry_inv2
   707   map_entry_is_rbt -> rbt_map_entry_is_rbt
   708   map_entry_sorted -> rbt_map_entry_rbt_sorted
   709   map_entry_tree_greater -> rbt_map_entry_rbt_greater
   710   map_entry_tree_less -> rbt_map_entry_rbt_less
   711   map_tree_greater -> map_rbt_greater
   712   map_tree_less -> map_rbt_less
   713   map_sorted -> map_rbt_sorted
   714   paint_sorted -> paint_rbt_sorted
   715   paint_lookup -> paint_rbt_lookup
   716   paint_tree_greater -> paint_rbt_greater
   717   paint_tree_less -> paint_rbt_less
   718   sorted_entries -> rbt_sorted_entries
   719   tree_greater_eq_trans -> rbt_greater_eq_trans
   720   tree_greater_nit -> rbt_greater_nit
   721   tree_greater_prop -> rbt_greater_prop
   722   tree_greater_simps -> rbt_greater_simps
   723   tree_greater_trans -> rbt_greater_trans
   724   tree_less_eq_trans -> rbt_less_eq_trans
   725   tree_less_nit -> rbt_less_nit
   726   tree_less_prop -> rbt_less_prop
   727   tree_less_simps -> rbt_less_simps
   728   tree_less_trans -> rbt_less_trans
   729   tree_ord_props -> rbt_ord_props
   730   union_Branch -> rbt_union_Branch
   731   union_is_rbt -> rbt_union_is_rbt
   732   unionw_is_rbt -> rbt_unionw_is_rbt
   733   unionwk_is_rbt -> rbt_unionwk_is_rbt
   734   unionwk_sorted -> rbt_unionwk_rbt_sorted
   735 
   736 * Theory HOL/Library/Float: Floating point numbers are now defined as
   737 a subset of the real numbers.  All operations are defined using the
   738 lifing-framework and proofs use the transfer method.  INCOMPATIBILITY.
   739 
   740   Changed Operations:
   741   float_abs -> abs
   742   float_nprt -> nprt
   743   float_pprt -> pprt
   744   pow2 -> use powr
   745   round_down -> float_round_down
   746   round_up -> float_round_up
   747   scale -> exponent
   748 
   749   Removed Operations:
   750   ceiling_fl, lb_mult, lb_mod, ub_mult, ub_mod
   751 
   752   Renamed Lemmas:
   753   abs_float_def -> Float.compute_float_abs
   754   bitlen_ge0 -> bitlen_nonneg
   755   bitlen.simps -> Float.compute_bitlen
   756   float_components -> Float_mantissa_exponent
   757   float_divl.simps -> Float.compute_float_divl
   758   float_divr.simps -> Float.compute_float_divr
   759   float_eq_odd -> mult_powr_eq_mult_powr_iff
   760   float_power -> real_of_float_power
   761   lapprox_posrat_def -> Float.compute_lapprox_posrat
   762   lapprox_rat.simps -> Float.compute_lapprox_rat
   763   le_float_def' -> Float.compute_float_le
   764   le_float_def -> less_eq_float.rep_eq
   765   less_float_def' -> Float.compute_float_less
   766   less_float_def -> less_float.rep_eq
   767   normfloat_def -> Float.compute_normfloat
   768   normfloat_imp_odd_or_zero -> mantissa_not_dvd and mantissa_noteq_0
   769   normfloat -> normfloat_def
   770   normfloat_unique -> use normfloat_def
   771   number_of_float_Float -> Float.compute_float_numeral, Float.compute_float_neg_numeral
   772   one_float_def -> Float.compute_float_one
   773   plus_float_def -> Float.compute_float_plus
   774   rapprox_posrat_def -> Float.compute_rapprox_posrat
   775   rapprox_rat.simps -> Float.compute_rapprox_rat
   776   real_of_float_0 -> zero_float.rep_eq
   777   real_of_float_1 -> one_float.rep_eq
   778   real_of_float_abs -> abs_float.rep_eq
   779   real_of_float_add -> plus_float.rep_eq
   780   real_of_float_minus -> uminus_float.rep_eq
   781   real_of_float_mult -> times_float.rep_eq
   782   real_of_float_simp -> Float.rep_eq
   783   real_of_float_sub -> minus_float.rep_eq
   784   round_down.simps -> Float.compute_float_round_down
   785   round_up.simps -> Float.compute_float_round_up
   786   times_float_def -> Float.compute_float_times
   787   uminus_float_def -> Float.compute_float_uminus
   788   zero_float_def -> Float.compute_float_zero
   789 
   790   Lemmas not necessary anymore, use the transfer method:
   791   bitlen_B0, bitlen_B1, bitlen_ge1, bitlen_Min, bitlen_Pls, float_divl,
   792   float_divr, float_le_simp, float_less1_mantissa_bound,
   793   float_less_simp, float_less_zero, float_le_zero,
   794   float_pos_less1_e_neg, float_pos_m_pos, float_split, float_split2,
   795   floor_pos_exp, lapprox_posrat, lapprox_posrat_bottom, lapprox_rat,
   796   lapprox_rat_bottom, normalized_float, rapprox_posrat,
   797   rapprox_posrat_le1, rapprox_rat, real_of_float_ge0_exp,
   798   real_of_float_neg_exp, real_of_float_nge0_exp, round_down floor_fl,
   799   round_up, zero_le_float, zero_less_float
   800 
   801 * New theory HOL/Library/DAList provides an abstract type for
   802 association lists with distinct keys.
   803 
   804 * Session HOL/IMP: Added new theory of abstract interpretation of
   805 annotated commands.
   806 
   807 * Session HOL-Import: Re-implementation from scratch is faster,
   808 simpler, and more scalable.  Requires a proof bundle, which is
   809 available as an external component.  Discontinued old (and mostly
   810 dead) Importer for HOL4 and HOL Light.  INCOMPATIBILITY.
   811 
   812 * Session HOL-Word: Discontinued many redundant theorems specific to
   813 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
   814 instead.
   815 
   816   word_sub_alt ~> word_sub_wi
   817   word_add_alt ~> word_add_def
   818   word_mult_alt ~> word_mult_def
   819   word_minus_alt ~> word_minus_def
   820   word_0_alt ~> word_0_wi
   821   word_1_alt ~> word_1_wi
   822   word_add_0 ~> add_0_left
   823   word_add_0_right ~> add_0_right
   824   word_mult_1 ~> mult_1_left
   825   word_mult_1_right ~> mult_1_right
   826   word_add_commute ~> add_commute
   827   word_add_assoc ~> add_assoc
   828   word_add_left_commute ~> add_left_commute
   829   word_mult_commute ~> mult_commute
   830   word_mult_assoc ~> mult_assoc
   831   word_mult_left_commute ~> mult_left_commute
   832   word_left_distrib ~> left_distrib
   833   word_right_distrib ~> right_distrib
   834   word_left_minus ~> left_minus
   835   word_diff_0_right ~> diff_0_right
   836   word_diff_self ~> diff_self
   837   word_sub_def ~> diff_minus
   838   word_diff_minus ~> diff_minus
   839   word_add_ac ~> add_ac
   840   word_mult_ac ~> mult_ac
   841   word_plus_ac0 ~> add_0_left add_0_right add_ac
   842   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
   843   word_order_trans ~> order_trans
   844   word_order_refl ~> order_refl
   845   word_order_antisym ~> order_antisym
   846   word_order_linear ~> linorder_linear
   847   lenw1_zero_neq_one ~> zero_neq_one
   848   word_number_of_eq ~> number_of_eq
   849   word_of_int_add_hom ~> wi_hom_add
   850   word_of_int_sub_hom ~> wi_hom_sub
   851   word_of_int_mult_hom ~> wi_hom_mult
   852   word_of_int_minus_hom ~> wi_hom_neg
   853   word_of_int_succ_hom ~> wi_hom_succ
   854   word_of_int_pred_hom ~> wi_hom_pred
   855   word_of_int_0_hom ~> word_0_wi
   856   word_of_int_1_hom ~> word_1_wi
   857 
   858 * Session HOL-Word: New proof method "word_bitwise" for splitting
   859 machine word equalities and inequalities into logical circuits,
   860 defined in HOL/Word/WordBitwise.thy.  Supports addition, subtraction,
   861 multiplication, shifting by constants, bitwise operators and numeric
   862 constants.  Requires fixed-length word types, not 'a word.  Solves
   863 many standard word identities outright and converts more into first
   864 order problems amenable to blast or similar.  See also examples in
   865 HOL/Word/Examples/WordExamples.thy.
   866 
   867 * Session HOL-Probability: Introduced the type "'a measure" to
   868 represent measures, this replaces the records 'a algebra and 'a
   869 measure_space.  The locales based on subset_class now have two
   870 locale-parameters the space \<Omega> and the set of measurable sets M.
   871 The product of probability spaces uses now the same constant as the
   872 finite product of sigma-finite measure spaces "PiM :: ('i => 'a)
   873 measure".  Most constants are defined now outside of locales and gain
   874 an additional parameter, like null_sets, almost_eventually or \<mu>'.
   875 Measure space constructions for distributions and densities now got
   876 their own constants distr and density.  Instead of using locales to
   877 describe measure spaces with a finite space, the measure count_space
   878 and point_measure is introduced.  INCOMPATIBILITY.
   879 
   880   Renamed constants:
   881   measure -> emeasure
   882   finite_measure.\<mu>' -> measure
   883   product_algebra_generator -> prod_algebra
   884   product_prob_space.emb -> prod_emb
   885   product_prob_space.infprod_algebra -> PiM
   886 
   887   Removed locales:
   888   completeable_measure_space
   889   finite_measure_space
   890   finite_prob_space
   891   finite_product_finite_prob_space
   892   finite_product_sigma_algebra
   893   finite_sigma_algebra
   894   measure_space
   895   pair_finite_prob_space
   896   pair_finite_sigma_algebra
   897   pair_finite_space
   898   pair_sigma_algebra
   899   product_sigma_algebra
   900 
   901   Removed constants:
   902   conditional_space
   903   distribution -> use distr measure, or distributed predicate
   904   image_space
   905   joint_distribution -> use distr measure, or distributed predicate
   906   pair_measure_generator
   907   product_prob_space.infprod_algebra -> use PiM
   908   subvimage
   909 
   910   Replacement theorems:
   911   finite_additivity_sufficient -> ring_of_sets.countably_additiveI_finite
   912   finite_measure.empty_measure -> measure_empty
   913   finite_measure.finite_continuity_from_above -> finite_measure.finite_Lim_measure_decseq
   914   finite_measure.finite_continuity_from_below -> finite_measure.finite_Lim_measure_incseq
   915   finite_measure.finite_measure_countably_subadditive -> finite_measure.finite_measure_subadditive_countably
   916   finite_measure.finite_measure_eq -> finite_measure.emeasure_eq_measure
   917   finite_measure.finite_measure -> finite_measure.emeasure_finite
   918   finite_measure.finite_measure_finite_singleton -> finite_measure.finite_measure_eq_setsum_singleton
   919   finite_measure.positive_measure' -> measure_nonneg
   920   finite_measure.real_measure -> finite_measure.emeasure_real
   921   finite_product_prob_space.finite_measure_times -> finite_product_prob_space.finite_measure_PiM_emb
   922   finite_product_sigma_algebra.in_P -> sets_PiM_I_finite
   923   finite_product_sigma_algebra.P_empty -> space_PiM_empty, sets_PiM_empty
   924   information_space.conditional_entropy_eq -> information_space.conditional_entropy_simple_distributed
   925   information_space.conditional_entropy_positive -> information_space.conditional_entropy_nonneg_simple
   926   information_space.conditional_mutual_information_eq_mutual_information -> information_space.conditional_mutual_information_eq_mutual_information_simple
   927   information_space.conditional_mutual_information_generic_positive -> information_space.conditional_mutual_information_nonneg_simple
   928   information_space.conditional_mutual_information_positive -> information_space.conditional_mutual_information_nonneg_simple
   929   information_space.entropy_commute -> information_space.entropy_commute_simple
   930   information_space.entropy_eq -> information_space.entropy_simple_distributed
   931   information_space.entropy_generic_eq -> information_space.entropy_simple_distributed
   932   information_space.entropy_positive -> information_space.entropy_nonneg_simple
   933   information_space.entropy_uniform_max -> information_space.entropy_uniform
   934   information_space.KL_eq_0_imp -> information_space.KL_eq_0_iff_eq
   935   information_space.KL_eq_0 -> information_space.KL_same_eq_0
   936   information_space.KL_ge_0 -> information_space.KL_nonneg
   937   information_space.mutual_information_eq -> information_space.mutual_information_simple_distributed
   938   information_space.mutual_information_positive -> information_space.mutual_information_nonneg_simple
   939   Int_stable_cuboids -> Int_stable_atLeastAtMost
   940   Int_stable_product_algebra_generator -> positive_integral
   941   measure_preserving -> equality "distr M N f = N" "f : measurable M N"
   942   measure_space.additive -> emeasure_additive
   943   measure_space.AE_iff_null_set -> AE_iff_null
   944   measure_space.almost_everywhere_def -> eventually_ae_filter
   945   measure_space.almost_everywhere_vimage -> AE_distrD
   946   measure_space.continuity_from_above -> INF_emeasure_decseq
   947   measure_space.continuity_from_above_Lim -> Lim_emeasure_decseq
   948   measure_space.continuity_from_below_Lim -> Lim_emeasure_incseq
   949   measure_space.continuity_from_below -> SUP_emeasure_incseq
   950   measure_space_density -> emeasure_density
   951   measure_space.density_is_absolutely_continuous -> absolutely_continuousI_density
   952   measure_space.integrable_vimage -> integrable_distr
   953   measure_space.integral_translated_density -> integral_density
   954   measure_space.integral_vimage -> integral_distr
   955   measure_space.measure_additive -> plus_emeasure
   956   measure_space.measure_compl -> emeasure_compl
   957   measure_space.measure_countable_increasing -> emeasure_countable_increasing
   958   measure_space.measure_countably_subadditive -> emeasure_subadditive_countably
   959   measure_space.measure_decseq -> decseq_emeasure
   960   measure_space.measure_Diff -> emeasure_Diff
   961   measure_space.measure_Diff_null_set -> emeasure_Diff_null_set
   962   measure_space.measure_eq_0 -> emeasure_eq_0
   963   measure_space.measure_finitely_subadditive -> emeasure_subadditive_finite
   964   measure_space.measure_finite_singleton -> emeasure_eq_setsum_singleton
   965   measure_space.measure_incseq -> incseq_emeasure
   966   measure_space.measure_insert -> emeasure_insert
   967   measure_space.measure_mono -> emeasure_mono
   968   measure_space.measure_not_negative -> emeasure_not_MInf
   969   measure_space.measure_preserving_Int_stable -> measure_eqI_generator_eq
   970   measure_space.measure_setsum -> setsum_emeasure
   971   measure_space.measure_setsum_split -> setsum_emeasure_cover
   972   measure_space.measure_space_vimage -> emeasure_distr
   973   measure_space.measure_subadditive_finite -> emeasure_subadditive_finite
   974   measure_space.measure_subadditive -> subadditive
   975   measure_space.measure_top -> emeasure_space
   976   measure_space.measure_UN_eq_0 -> emeasure_UN_eq_0
   977   measure_space.measure_Un_null_set -> emeasure_Un_null_set
   978   measure_space.positive_integral_translated_density -> positive_integral_density
   979   measure_space.positive_integral_vimage -> positive_integral_distr
   980   measure_space.real_continuity_from_above -> Lim_measure_decseq
   981   measure_space.real_continuity_from_below -> Lim_measure_incseq
   982   measure_space.real_measure_countably_subadditive -> measure_subadditive_countably
   983   measure_space.real_measure_Diff -> measure_Diff
   984   measure_space.real_measure_finite_Union -> measure_finite_Union
   985   measure_space.real_measure_setsum_singleton -> measure_eq_setsum_singleton
   986   measure_space.real_measure_subadditive -> measure_subadditive
   987   measure_space.real_measure_Union -> measure_Union
   988   measure_space.real_measure_UNION -> measure_UNION
   989   measure_space.simple_function_vimage -> simple_function_comp
   990   measure_space.simple_integral_vimage -> simple_integral_distr
   991   measure_space.simple_integral_vimage -> simple_integral_distr
   992   measure_unique_Int_stable -> measure_eqI_generator_eq
   993   measure_unique_Int_stable_vimage -> measure_eqI_generator_eq
   994   pair_sigma_algebra.measurable_cut_fst -> sets_Pair1
   995   pair_sigma_algebra.measurable_cut_snd -> sets_Pair2
   996   pair_sigma_algebra.measurable_pair_image_fst -> measurable_Pair1
   997   pair_sigma_algebra.measurable_pair_image_snd -> measurable_Pair2
   998   pair_sigma_algebra.measurable_product_swap -> measurable_pair_swap_iff
   999   pair_sigma_algebra.pair_sigma_algebra_measurable -> measurable_pair_swap
  1000   pair_sigma_algebra.pair_sigma_algebra_swap_measurable -> measurable_pair_swap'
  1001   pair_sigma_algebra.sets_swap -> sets_pair_swap
  1002   pair_sigma_finite.measure_cut_measurable_fst -> pair_sigma_finite.measurable_emeasure_Pair1
  1003   pair_sigma_finite.measure_cut_measurable_snd -> pair_sigma_finite.measurable_emeasure_Pair2
  1004   pair_sigma_finite.measure_preserving_swap -> pair_sigma_finite.distr_pair_swap
  1005   pair_sigma_finite.pair_measure_alt2 -> pair_sigma_finite.emeasure_pair_measure_alt2
  1006   pair_sigma_finite.pair_measure_alt -> pair_sigma_finite.emeasure_pair_measure_alt
  1007   pair_sigma_finite.pair_measure_times -> pair_sigma_finite.emeasure_pair_measure_Times
  1008   prob_space.indep_distribution_eq_measure -> prob_space.indep_vars_iff_distr_eq_PiM
  1009   prob_space.indep_var_distributionD -> prob_space.indep_var_distribution_eq
  1010   prob_space.measure_space_1 -> prob_space.emeasure_space_1
  1011   prob_space.prob_space_vimage -> prob_space_distr
  1012   prob_space.random_variable_restrict -> measurable_restrict
  1013   prob_space_unique_Int_stable -> measure_eqI_prob_space
  1014   product_algebraE -> prod_algebraE_all
  1015   product_algebra_generator_der -> prod_algebra_eq_finite
  1016   product_algebra_generator_into_space -> prod_algebra_sets_into_space
  1017   product_algebraI -> sets_PiM_I_finite
  1018   product_measure_exists -> product_sigma_finite.sigma_finite
  1019   product_prob_space.finite_index_eq_finite_product -> product_prob_space.sets_PiM_generator
  1020   product_prob_space.finite_measure_infprod_emb_Pi -> product_prob_space.measure_PiM_emb
  1021   product_prob_space.infprod_spec -> product_prob_space.emeasure_PiM_emb_not_empty
  1022   product_prob_space.measurable_component -> measurable_component_singleton
  1023   product_prob_space.measurable_emb -> measurable_prod_emb
  1024   product_prob_space.measurable_into_infprod_algebra -> measurable_PiM_single
  1025   product_prob_space.measurable_singleton_infprod -> measurable_component_singleton
  1026   product_prob_space.measure_emb -> emeasure_prod_emb
  1027   product_prob_space.measure_preserving_restrict -> product_prob_space.distr_restrict
  1028   product_sigma_algebra.product_algebra_into_space -> space_closed
  1029   product_sigma_finite.measure_fold -> product_sigma_finite.distr_merge
  1030   product_sigma_finite.measure_preserving_component_singelton -> product_sigma_finite.distr_singleton
  1031   product_sigma_finite.measure_preserving_merge -> product_sigma_finite.distr_merge
  1032   sequence_space.measure_infprod -> sequence_space.measure_PiM_countable
  1033   sets_product_algebra -> sets_PiM
  1034   sigma_algebra.measurable_sigma -> measurable_measure_of
  1035   sigma_finite_measure.disjoint_sigma_finite -> sigma_finite_disjoint
  1036   sigma_finite_measure.RN_deriv_vimage -> sigma_finite_measure.RN_deriv_distr
  1037   sigma_product_algebra_sigma_eq -> sigma_prod_algebra_sigma_eq
  1038   space_product_algebra -> space_PiM
  1039 
  1040 * Session HOL-TPTP: support to parse and import TPTP problems (all
  1041 languages) into Isabelle/HOL.
  1042 
  1043 
  1044 *** FOL ***
  1045 
  1046 * New "case_product" attribute (see HOL).
  1047 
  1048 
  1049 *** ZF ***
  1050 
  1051 * Greater support for structured proofs involving induction or case
  1052 analysis.
  1053 
  1054 * Much greater use of mathematical symbols.
  1055 
  1056 * Removal of many ML theorem bindings.  INCOMPATIBILITY.
  1057 
  1058 
  1059 *** ML ***
  1060 
  1061 * Antiquotation @{keyword "name"} produces a parser for outer syntax
  1062 from a minor keyword introduced via theory header declaration.
  1063 
  1064 * Antiquotation @{command_spec "name"} produces the
  1065 Outer_Syntax.command_spec from a major keyword introduced via theory
  1066 header declaration; it can be passed to Outer_Syntax.command etc.
  1067 
  1068 * Local_Theory.define no longer hard-wires default theorem name
  1069 "foo_def", but retains the binding as given.  If that is Binding.empty
  1070 / Attrib.empty_binding, the result is not registered as user-level
  1071 fact.  The Local_Theory.define_internal variant allows to specify a
  1072 non-empty name (used for the foundation in the background theory),
  1073 while omitting the fact binding in the user-context.  Potential
  1074 INCOMPATIBILITY for derived definitional packages: need to specify
  1075 naming policy for primitive definitions more explicitly.
  1076 
  1077 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
  1078 conformance with similar operations in structure Term and Logic.
  1079 
  1080 * Antiquotation @{attributes [...]} embeds attribute source
  1081 representation into the ML text, which is particularly useful with
  1082 declarations like Local_Theory.note.
  1083 
  1084 * Structure Proof_Context follows standard naming scheme.  Old
  1085 ProofContext has been discontinued.  INCOMPATIBILITY.
  1086 
  1087 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
  1088 change of semantics: update is applied to auxiliary local theory
  1089 context as well.
  1090 
  1091 * Modernized some old-style infix operations:
  1092 
  1093   addeqcongs    ~> Simplifier.add_eqcong
  1094   deleqcongs    ~> Simplifier.del_eqcong
  1095   addcongs      ~> Simplifier.add_cong
  1096   delcongs      ~> Simplifier.del_cong
  1097   setmksimps    ~> Simplifier.set_mksimps
  1098   setmkcong     ~> Simplifier.set_mkcong
  1099   setmksym      ~> Simplifier.set_mksym
  1100   setmkeqTrue   ~> Simplifier.set_mkeqTrue
  1101   settermless   ~> Simplifier.set_termless
  1102   setsubgoaler  ~> Simplifier.set_subgoaler
  1103   addsplits     ~> Splitter.add_split
  1104   delsplits     ~> Splitter.del_split
  1105 
  1106 
  1107 *** System ***
  1108 
  1109 * USER_HOME settings variable points to cross-platform user home
  1110 directory, which coincides with HOME on POSIX systems only.  Likewise,
  1111 the Isabelle path specification "~" now expands to $USER_HOME, instead
  1112 of former $HOME.  A different default for USER_HOME may be set
  1113 explicitly in shell environment, before Isabelle settings are
  1114 evaluated.  Minor INCOMPATIBILITY: need to adapt Isabelle path where
  1115 the generic user home was intended.
  1116 
  1117 * ISABELLE_HOME_WINDOWS refers to ISABELLE_HOME in windows file name
  1118 notation, which is useful for the jEdit file browser, for example.
  1119 
  1120 * ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
  1121 (not just JRE).
  1122 
  1123 
  1124 
  1125 New in Isabelle2011-1 (October 2011)
  1126 ------------------------------------
  1127 
  1128 *** General ***
  1129 
  1130 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
  1131 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
  1132 
  1133   - Management of multiple theory files directly from the editor
  1134     buffer store -- bypassing the file-system (no requirement to save
  1135     files for checking).
  1136 
  1137   - Markup of formal entities within the text buffer, with semantic
  1138     highlighting, tooltips and hyperlinks to jump to defining source
  1139     positions.
  1140 
  1141   - Improved text rendering, with sub/superscripts in the source
  1142     buffer (including support for copy/paste wrt. output panel, HTML
  1143     theory output and other non-Isabelle text boxes).
  1144 
  1145   - Refined scheduling of proof checking and printing of results,
  1146     based on interactive editor view.  (Note: jEdit folding and
  1147     narrowing allows to restrict buffer perspectives explicitly.)
  1148 
  1149   - Reduced CPU performance requirements, usable on machines with few
  1150     cores.
  1151 
  1152   - Reduced memory requirements due to pruning of unused document
  1153     versions (garbage collection).
  1154 
  1155 See also ~~/src/Tools/jEdit/README.html for further information,
  1156 including some remaining limitations.
  1157 
  1158 * Theory loader: source files are exclusively located via the master
  1159 directory of each theory node (where the .thy file itself resides).
  1160 The global load path (such as src/HOL/Library) has been discontinued.
  1161 Note that the path element ~~ may be used to reference theories in the
  1162 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
  1163 INCOMPATIBILITY.
  1164 
  1165 * Theory loader: source files are identified by content via SHA1
  1166 digests.  Discontinued former path/modtime identification and optional
  1167 ISABELLE_FILE_IDENT plugin scripts.
  1168 
  1169 * Parallelization of nested Isar proofs is subject to
  1170 Goal.parallel_proofs_threshold (default 100).  See also isabelle
  1171 usedir option -Q.
  1172 
  1173 * Name space: former unsynchronized references are now proper
  1174 configuration options, with more conventional names:
  1175 
  1176   long_names   ~> names_long
  1177   short_names  ~> names_short
  1178   unique_names ~> names_unique
  1179 
  1180 Minor INCOMPATIBILITY, need to declare options in context like this:
  1181 
  1182   declare [[names_unique = false]]
  1183 
  1184 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
  1185 that the result needs to be unique, which means fact specifications
  1186 may have to be refined after enriching a proof context.
  1187 
  1188 * Attribute "case_names" has been refined: the assumptions in each case
  1189 can be named now by following the case name with [name1 name2 ...].
  1190 
  1191 * Isabelle/Isar reference manual has been updated and extended:
  1192   - "Synopsis" provides a catalog of main Isar language concepts.
  1193   - Formal references in syntax diagrams, via @{rail} antiquotation.
  1194   - Updated material from classic "ref" manual, notably about
  1195     "Classical Reasoner".
  1196 
  1197 
  1198 *** HOL ***
  1199 
  1200 * Class bot and top require underlying partial order rather than
  1201 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
  1202 
  1203 * Class complete_lattice: generalized a couple of lemmas from sets;
  1204 generalized theorems INF_cong and SUP_cong.  New type classes for
  1205 complete boolean algebras and complete linear orders.  Lemmas
  1206 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
  1207 class complete_linorder.
  1208 
  1209 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
  1210 Sup_fun_def, Inf_apply, Sup_apply.
  1211 
  1212 Removed redundant lemmas (the right hand side gives hints how to
  1213 replace them for (metis ...), or (simp only: ...) proofs):
  1214 
  1215   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
  1216   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
  1217   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
  1218   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
  1219   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
  1220   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
  1221   Inter_def ~> INF_def, image_def
  1222   Union_def ~> SUP_def, image_def
  1223   INT_eq ~> INF_def, and image_def
  1224   UN_eq ~> SUP_def, and image_def
  1225   INF_subset ~> INF_superset_mono [OF _ order_refl]
  1226 
  1227 More consistent and comprehensive names:
  1228 
  1229   INTER_eq_Inter_image ~> INF_def
  1230   UNION_eq_Union_image ~> SUP_def
  1231   INFI_def ~> INF_def
  1232   SUPR_def ~> SUP_def
  1233   INF_leI ~> INF_lower
  1234   INF_leI2 ~> INF_lower2
  1235   le_INFI ~> INF_greatest
  1236   le_SUPI ~> SUP_upper
  1237   le_SUPI2 ~> SUP_upper2
  1238   SUP_leI ~> SUP_least
  1239   INFI_bool_eq ~> INF_bool_eq
  1240   SUPR_bool_eq ~> SUP_bool_eq
  1241   INFI_apply ~> INF_apply
  1242   SUPR_apply ~> SUP_apply
  1243   INTER_def ~> INTER_eq
  1244   UNION_def ~> UNION_eq
  1245 
  1246 INCOMPATIBILITY.
  1247 
  1248 * Renamed theory Complete_Lattice to Complete_Lattices.
  1249 INCOMPATIBILITY.
  1250 
  1251 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
  1252 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
  1253 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
  1254 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
  1255 
  1256 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
  1257 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
  1258 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
  1259 INCOMPATIBILITY.
  1260 
  1261 * Added syntactic classes "inf" and "sup" for the respective
  1262 constants.  INCOMPATIBILITY: Changes in the argument order of the
  1263 (mostly internal) locale predicates for some derived classes.
  1264 
  1265 * Theorem collections ball_simps and bex_simps do not contain theorems
  1266 referring to UNION any longer; these have been moved to collection
  1267 UN_ball_bex_simps.  INCOMPATIBILITY.
  1268 
  1269 * Theory Archimedean_Field: floor now is defined as parameter of a
  1270 separate type class floor_ceiling.
  1271 
  1272 * Theory Finite_Set: more coherent development of fold_set locales:
  1273 
  1274     locale fun_left_comm ~> locale comp_fun_commute
  1275     locale fun_left_comm_idem ~> locale comp_fun_idem
  1276 
  1277 Both use point-free characterization; interpretation proofs may need
  1278 adjustment.  INCOMPATIBILITY.
  1279 
  1280 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
  1281 accordance with standard mathematical terminology. INCOMPATIBILITY.
  1282 
  1283 * Theory Complex_Main: The locale interpretations for the
  1284 bounded_linear and bounded_bilinear locales have been removed, in
  1285 order to reduce the number of duplicate lemmas. Users must use the
  1286 original names for distributivity theorems, potential INCOMPATIBILITY.
  1287 
  1288   divide.add ~> add_divide_distrib
  1289   divide.diff ~> diff_divide_distrib
  1290   divide.setsum ~> setsum_divide_distrib
  1291   mult.add_right ~> right_distrib
  1292   mult.diff_right ~> right_diff_distrib
  1293   mult_right.setsum ~> setsum_right_distrib
  1294   mult_left.diff ~> left_diff_distrib
  1295 
  1296 * Theory Complex_Main: Several redundant theorems have been removed or
  1297 replaced by more general versions. INCOMPATIBILITY.
  1298 
  1299   real_diff_def ~> minus_real_def
  1300   real_divide_def ~> divide_real_def
  1301   real_less_def ~> less_le
  1302   real_abs_def ~> abs_real_def
  1303   real_sgn_def ~> sgn_real_def
  1304   real_mult_commute ~> mult_commute
  1305   real_mult_assoc ~> mult_assoc
  1306   real_mult_1 ~> mult_1_left
  1307   real_add_mult_distrib ~> left_distrib
  1308   real_zero_not_eq_one ~> zero_neq_one
  1309   real_mult_inverse_left ~> left_inverse
  1310   INVERSE_ZERO ~> inverse_zero
  1311   real_le_refl ~> order_refl
  1312   real_le_antisym ~> order_antisym
  1313   real_le_trans ~> order_trans
  1314   real_le_linear ~> linear
  1315   real_le_eq_diff ~> le_iff_diff_le_0
  1316   real_add_left_mono ~> add_left_mono
  1317   real_mult_order ~> mult_pos_pos
  1318   real_mult_less_mono2 ~> mult_strict_left_mono
  1319   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
  1320   real_0_le_divide_iff ~> zero_le_divide_iff
  1321   realpow_two_disj ~> power2_eq_iff
  1322   real_squared_diff_one_factored ~> square_diff_one_factored
  1323   realpow_two_diff ~> square_diff_square_factored
  1324   reals_complete2 ~> complete_real
  1325   real_sum_squared_expand ~> power2_sum
  1326   exp_ln_eq ~> ln_unique
  1327   expi_add ~> exp_add
  1328   expi_zero ~> exp_zero
  1329   lemma_DERIV_subst ~> DERIV_cong
  1330   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
  1331   LIMSEQ_const ~> tendsto_const
  1332   LIMSEQ_norm ~> tendsto_norm
  1333   LIMSEQ_add ~> tendsto_add
  1334   LIMSEQ_minus ~> tendsto_minus
  1335   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
  1336   LIMSEQ_diff ~> tendsto_diff
  1337   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
  1338   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
  1339   LIMSEQ_mult ~> tendsto_mult
  1340   LIMSEQ_inverse ~> tendsto_inverse
  1341   LIMSEQ_divide ~> tendsto_divide
  1342   LIMSEQ_pow ~> tendsto_power
  1343   LIMSEQ_setsum ~> tendsto_setsum
  1344   LIMSEQ_setprod ~> tendsto_setprod
  1345   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
  1346   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
  1347   LIMSEQ_imp_rabs ~> tendsto_rabs
  1348   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
  1349   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
  1350   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
  1351   LIMSEQ_Complex ~> tendsto_Complex
  1352   LIM_ident ~> tendsto_ident_at
  1353   LIM_const ~> tendsto_const
  1354   LIM_add ~> tendsto_add
  1355   LIM_add_zero ~> tendsto_add_zero
  1356   LIM_minus ~> tendsto_minus
  1357   LIM_diff ~> tendsto_diff
  1358   LIM_norm ~> tendsto_norm
  1359   LIM_norm_zero ~> tendsto_norm_zero
  1360   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
  1361   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
  1362   LIM_rabs ~> tendsto_rabs
  1363   LIM_rabs_zero ~> tendsto_rabs_zero
  1364   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
  1365   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
  1366   LIM_compose ~> tendsto_compose
  1367   LIM_mult ~> tendsto_mult
  1368   LIM_scaleR ~> tendsto_scaleR
  1369   LIM_of_real ~> tendsto_of_real
  1370   LIM_power ~> tendsto_power
  1371   LIM_inverse ~> tendsto_inverse
  1372   LIM_sgn ~> tendsto_sgn
  1373   isCont_LIM_compose ~> isCont_tendsto_compose
  1374   bounded_linear.LIM ~> bounded_linear.tendsto
  1375   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
  1376   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
  1377   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
  1378   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
  1379   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
  1380   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
  1381 
  1382 * Theory Complex_Main: The definition of infinite series was
  1383 generalized.  Now it is defined on the type class {topological_space,
  1384 comm_monoid_add}.  Hence it is useable also for extended real numbers.
  1385 
  1386 * Theory Complex_Main: The complex exponential function "expi" is now
  1387 a type-constrained abbreviation for "exp :: complex => complex"; thus
  1388 several polymorphic lemmas about "exp" are now applicable to "expi".
  1389 
  1390 * Code generation:
  1391 
  1392   - Theory Library/Code_Char_ord provides native ordering of
  1393     characters in the target language.
  1394 
  1395   - Commands code_module and code_library are legacy, use export_code
  1396     instead.
  1397 
  1398   - Method "evaluation" is legacy, use method "eval" instead.
  1399 
  1400   - Legacy evaluator "SML" is deactivated by default.  May be
  1401     reactivated by the following theory command:
  1402 
  1403       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
  1404 
  1405 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
  1406 
  1407 * New proof method "induction" that gives induction hypotheses the
  1408 name "IH", thus distinguishing them from further hypotheses that come
  1409 from rule induction.  The latter are still called "hyps".  Method
  1410 "induction" is a thin wrapper around "induct" and follows the same
  1411 syntax.
  1412 
  1413 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
  1414 still available as a legacy feature for some time.
  1415 
  1416 * Nitpick:
  1417   - Added "need" and "total_consts" options.
  1418   - Reintroduced "show_skolems" option by popular demand.
  1419   - Renamed attribute: nitpick_def ~> nitpick_unfold.
  1420     INCOMPATIBILITY.
  1421 
  1422 * Sledgehammer:
  1423   - Use quasi-sound (and efficient) translations by default.
  1424   - Added support for the following provers: E-ToFoF, LEO-II,
  1425     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
  1426   - Automatically preplay and minimize proofs before showing them if
  1427     this can be done within reasonable time.
  1428   - sledgehammer available_provers ~> sledgehammer supported_provers.
  1429     INCOMPATIBILITY.
  1430   - Added "preplay_timeout", "slicing", "type_enc", "sound",
  1431     "max_mono_iters", and "max_new_mono_instances" options.
  1432   - Removed "explicit_apply" and "full_types" options as well as "Full
  1433     Types" Proof General menu item. INCOMPATIBILITY.
  1434 
  1435 * Metis:
  1436   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
  1437   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
  1438     INCOMPATIBILITY.
  1439 
  1440 * Command 'try':
  1441   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
  1442     "elim:" options. INCOMPATIBILITY.
  1443   - Introduced 'try' that not only runs 'try_methods' but also
  1444     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
  1445 
  1446 * Quickcheck:
  1447   - Added "eval" option to evaluate terms for the found counterexample
  1448     (currently only supported by the default (exhaustive) tester).
  1449   - Added post-processing of terms to obtain readable counterexamples
  1450     (currently only supported by the default (exhaustive) tester).
  1451   - New counterexample generator quickcheck[narrowing] enables
  1452     narrowing-based testing.  Requires the Glasgow Haskell compiler
  1453     with its installation location defined in the Isabelle settings
  1454     environment as ISABELLE_GHC.
  1455   - Removed quickcheck tester "SML" based on the SML code generator
  1456     (formly in HOL/Library).
  1457 
  1458 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
  1459 use 'partial_function' instead.
  1460 
  1461 * Theory Library/Extended_Reals replaces now the positive extended
  1462 reals found in probability theory. This file is extended by
  1463 Multivariate_Analysis/Extended_Real_Limits.
  1464 
  1465 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
  1466 from where it must be imported explicitly if it is really required.
  1467 INCOMPATIBILITY.
  1468 
  1469 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
  1470 been moved here.  INCOMPATIBILITY.
  1471 
  1472 * Theory Library/Saturated provides type of numbers with saturated
  1473 arithmetic.
  1474 
  1475 * Theory Library/Product_Lattice defines a pointwise ordering for the
  1476 product type 'a * 'b, and provides instance proofs for various order
  1477 and lattice type classes.
  1478 
  1479 * Theory Library/Countable now provides the "countable_datatype" proof
  1480 method for proving "countable" class instances for datatypes.
  1481 
  1482 * Theory Library/Cset_Monad allows do notation for computable sets
  1483 (cset) via the generic monad ad-hoc overloading facility.
  1484 
  1485 * Library: Theories of common data structures are split into theories
  1486 for implementation, an invariant-ensuring type, and connection to an
  1487 abstract type. INCOMPATIBILITY.
  1488 
  1489   - RBT is split into RBT and RBT_Mapping.
  1490   - AssocList is split and renamed into AList and AList_Mapping.
  1491   - DList is split into DList_Impl, DList, and DList_Cset.
  1492   - Cset is split into Cset and List_Cset.
  1493 
  1494 * Theory Library/Nat_Infinity has been renamed to
  1495 Library/Extended_Nat, with name changes of the following types and
  1496 constants:
  1497 
  1498   type inat   ~> type enat
  1499   Fin         ~> enat
  1500   Infty       ~> infinity (overloaded)
  1501   iSuc        ~> eSuc
  1502   the_Fin     ~> the_enat
  1503 
  1504 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
  1505 been renamed accordingly. INCOMPATIBILITY.
  1506 
  1507 * Session Multivariate_Analysis: The euclidean_space type class now
  1508 fixes a constant "Basis :: 'a set" consisting of the standard
  1509 orthonormal basis for the type. Users now have the option of
  1510 quantifying over this set instead of using the "basis" function, e.g.
  1511 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
  1512 
  1513 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
  1514 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
  1515 "Cart_nth" and "Cart_lambda" have been respectively renamed to
  1516 "vec_nth" and "vec_lambda"; theorems mentioning those names have
  1517 changed to match. Definition theorems for overloaded constants now use
  1518 the standard "foo_vec_def" naming scheme. A few other theorems have
  1519 been renamed as follows (INCOMPATIBILITY):
  1520 
  1521   Cart_eq          ~> vec_eq_iff
  1522   dist_nth_le_cart ~> dist_vec_nth_le
  1523   tendsto_vector   ~> vec_tendstoI
  1524   Cauchy_vector    ~> vec_CauchyI
  1525 
  1526 * Session Multivariate_Analysis: Several duplicate theorems have been
  1527 removed, and other theorems have been renamed or replaced with more
  1528 general versions. INCOMPATIBILITY.
  1529 
  1530   finite_choice ~> finite_set_choice
  1531   eventually_conjI ~> eventually_conj
  1532   eventually_and ~> eventually_conj_iff
  1533   eventually_false ~> eventually_False
  1534   setsum_norm ~> norm_setsum
  1535   Lim_sequentially ~> LIMSEQ_def
  1536   Lim_ident_at ~> LIM_ident
  1537   Lim_const ~> tendsto_const
  1538   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
  1539   Lim_neg ~> tendsto_minus
  1540   Lim_add ~> tendsto_add
  1541   Lim_sub ~> tendsto_diff
  1542   Lim_mul ~> tendsto_scaleR
  1543   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
  1544   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
  1545   Lim_linear ~> bounded_linear.tendsto
  1546   Lim_component ~> tendsto_euclidean_component
  1547   Lim_component_cart ~> tendsto_vec_nth
  1548   Lim_inner ~> tendsto_inner [OF tendsto_const]
  1549   dot_lsum ~> inner_setsum_left
  1550   dot_rsum ~> inner_setsum_right
  1551   continuous_cmul ~> continuous_scaleR [OF continuous_const]
  1552   continuous_neg ~> continuous_minus
  1553   continuous_sub ~> continuous_diff
  1554   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
  1555   continuous_mul ~> continuous_scaleR
  1556   continuous_inv ~> continuous_inverse
  1557   continuous_at_within_inv ~> continuous_at_within_inverse
  1558   continuous_at_inv ~> continuous_at_inverse
  1559   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
  1560   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
  1561   continuous_at_component ~> continuous_component [OF continuous_at_id]
  1562   continuous_on_neg ~> continuous_on_minus
  1563   continuous_on_sub ~> continuous_on_diff
  1564   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
  1565   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
  1566   continuous_on_mul ~> continuous_on_scaleR
  1567   continuous_on_mul_real ~> continuous_on_mult
  1568   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
  1569   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
  1570   continuous_on_inverse ~> continuous_on_inv
  1571   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
  1572   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
  1573   subset_interior ~> interior_mono
  1574   subset_closure ~> closure_mono
  1575   closure_univ ~> closure_UNIV
  1576   real_arch_lt ~> reals_Archimedean2
  1577   real_arch ~> reals_Archimedean3
  1578   real_abs_norm ~> abs_norm_cancel
  1579   real_abs_sub_norm ~> norm_triangle_ineq3
  1580   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
  1581 
  1582 * Session HOL-Probability:
  1583   - Caratheodory's extension lemma is now proved for ring_of_sets.
  1584   - Infinite products of probability measures are now available.
  1585   - Sigma closure is independent, if the generator is independent
  1586   - Use extended reals instead of positive extended
  1587     reals. INCOMPATIBILITY.
  1588 
  1589 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
  1590 
  1591   expand_fun_below ~> fun_below_iff
  1592   below_fun_ext ~> fun_belowI
  1593   expand_cfun_eq ~> cfun_eq_iff
  1594   ext_cfun ~> cfun_eqI
  1595   expand_cfun_below ~> cfun_below_iff
  1596   below_cfun_ext ~> cfun_belowI
  1597   monofun_fun_fun ~> fun_belowD
  1598   monofun_fun_arg ~> monofunE
  1599   monofun_lub_fun ~> adm_monofun [THEN admD]
  1600   cont_lub_fun ~> adm_cont [THEN admD]
  1601   cont2cont_Rep_CFun ~> cont2cont_APP
  1602   cont_Rep_CFun_app ~> cont_APP_app
  1603   cont_Rep_CFun_app_app ~> cont_APP_app_app
  1604   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
  1605   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
  1606   contlub_cfun ~> lub_APP [symmetric]
  1607   contlub_LAM ~> lub_LAM [symmetric]
  1608   thelubI ~> lub_eqI
  1609   UU_I ~> bottomI
  1610   lift_distinct1 ~> lift.distinct(1)
  1611   lift_distinct2 ~> lift.distinct(2)
  1612   Def_not_UU ~> lift.distinct(2)
  1613   Def_inject ~> lift.inject
  1614   below_UU_iff ~> below_bottom_iff
  1615   eq_UU_iff ~> eq_bottom_iff
  1616 
  1617 
  1618 *** Document preparation ***
  1619 
  1620 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
  1621 isar-ref manual, both for description and actual application of the
  1622 same.
  1623 
  1624 * Antiquotation @{value} evaluates the given term and presents its
  1625 result.
  1626 
  1627 * Antiquotations: term style "isub" provides ad-hoc conversion of
  1628 variables x1, y23 into subscripted form x\<^isub>1,
  1629 y\<^isub>2\<^isub>3.
  1630 
  1631 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
  1632 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
  1633 
  1634 * Localized \isabellestyle switch can be used within blocks or groups
  1635 like this:
  1636 
  1637   \isabellestyle{it}  %preferred default
  1638   {\isabellestylett @{text "typewriter stuff"}}
  1639 
  1640 * Discontinued special treatment of hard tabulators.  Implicit
  1641 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
  1642 layouts.
  1643 
  1644 
  1645 *** ML ***
  1646 
  1647 * The inner syntax of sort/type/term/prop supports inlined YXML
  1648 representations within quoted string tokens.  By encoding logical
  1649 entities via Term_XML (in ML or Scala) concrete syntax can be
  1650 bypassed, which is particularly useful for producing bits of text
  1651 under external program control.
  1652 
  1653 * Antiquotations for ML and document preparation are managed as theory
  1654 data, which requires explicit setup.
  1655 
  1656 * Isabelle_Process.is_active allows tools to check if the official
  1657 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
  1658 (better known as Proof General).
  1659 
  1660 * Structure Proof_Context follows standard naming scheme.  Old
  1661 ProofContext is still available for some time as legacy alias.
  1662 
  1663 * Structure Timing provides various operations for timing; supersedes
  1664 former start_timing/end_timing etc.
  1665 
  1666 * Path.print is the official way to show file-system paths to users
  1667 (including quotes etc.).
  1668 
  1669 * Inner syntax: identifiers in parse trees of generic categories
  1670 "logic", "aprop", "idt" etc. carry position information (disguised as
  1671 type constraints).  Occasional INCOMPATIBILITY with non-compliant
  1672 translations that choke on unexpected type constraints.  Positions can
  1673 be stripped in ML translations via Syntax.strip_positions /
  1674 Syntax.strip_positions_ast, or via the syntax constant
  1675 "_strip_positions" within parse trees.  As last resort, positions can
  1676 be disabled via the configuration option Syntax.positions, which is
  1677 called "syntax_positions" in Isar attribute syntax.
  1678 
  1679 * Discontinued special status of various ML structures that contribute
  1680 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
  1681 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
  1682 refer directly to Ast.Constant, Lexicon.is_identifier,
  1683 Syntax_Trans.mk_binder_tr etc.
  1684 
  1685 * Typed print translation: discontinued show_sorts argument, which is
  1686 already available via context of "advanced" translation.
  1687 
  1688 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
  1689 goal states; body tactic needs to address all subgoals uniformly.
  1690 
  1691 * Slightly more special eq_list/eq_set, with shortcut involving
  1692 pointer equality (assumes that eq relation is reflexive).
  1693 
  1694 * Classical tactics use proper Proof.context instead of historic types
  1695 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  1696 operate directly on Proof.context.  Raw type claset retains its use as
  1697 snapshot of the classical context, which can be recovered via
  1698 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  1699 INCOMPATIBILITY, classical tactics and derived proof methods require
  1700 proper Proof.context.
  1701 
  1702 
  1703 *** System ***
  1704 
  1705 * Discontinued support for Poly/ML 5.2, which was the last version
  1706 without proper multithreading and TimeLimit implementation.
  1707 
  1708 * Discontinued old lib/scripts/polyml-platform, which has been
  1709 obsolete since Isabelle2009-2.
  1710 
  1711 * Various optional external tools are referenced more robustly and
  1712 uniformly by explicit Isabelle settings as follows:
  1713 
  1714   ISABELLE_CSDP   (formerly CSDP_EXE)
  1715   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  1716   ISABELLE_OCAML  (formerly EXEC_OCAML)
  1717   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  1718   ISABELLE_YAP    (formerly EXEC_YAP)
  1719 
  1720 Note that automated detection from the file-system or search path has
  1721 been discontinued.  INCOMPATIBILITY.
  1722 
  1723 * Scala layer provides JVM method invocation service for static
  1724 methods of type (String)String, see Invoke_Scala.method in ML.  For
  1725 example:
  1726 
  1727   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  1728 
  1729 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  1730 this allows to pass structured values between ML and Scala.
  1731 
  1732 * The IsabelleText fonts includes some further glyphs to support the
  1733 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  1734 installed a local copy (which is normally *not* required) need to
  1735 delete or update it from ~~/lib/fonts/.
  1736 
  1737 
  1738 
  1739 New in Isabelle2011 (January 2011)
  1740 ----------------------------------
  1741 
  1742 *** General ***
  1743 
  1744 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  1745 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  1746 useful tooltips and hyperlinks produced from its static analysis.  The
  1747 bundled component provides an executable Isabelle tool that can be run
  1748 like this:
  1749 
  1750   Isabelle2011/bin/isabelle jedit
  1751 
  1752 * Significantly improved Isabelle/Isar implementation manual.
  1753 
  1754 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  1755 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  1756 while the default heap location within that directory lacks that extra
  1757 suffix.  This isolates multiple Isabelle installations from each
  1758 other, avoiding problems with old settings in new versions.
  1759 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  1760 
  1761 * Source files are always encoded as UTF-8, instead of old-fashioned
  1762 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  1763 the following package declarations:
  1764 
  1765   \usepackage[utf8]{inputenc}
  1766   \usepackage{textcomp}
  1767 
  1768 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  1769 a Unicode character is treated as a single symbol, not a sequence of
  1770 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  1771 contain symbols without further backslash escapes, Unicode can now be
  1772 used here as well.  Recall that Symbol.explode in ML provides a
  1773 consistent view on symbols, while raw explode (or String.explode)
  1774 merely give a byte-oriented representation.
  1775 
  1776 * Theory loader: source files are primarily located via the master
  1777 directory of each theory node (where the .thy file itself resides).
  1778 The global load path is still partially available as legacy feature.
  1779 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  1780 explicit paths, relatively to the theory.
  1781 
  1782 * Special treatment of ML file names has been discontinued.
  1783 Historically, optional extensions .ML or .sml were added on demand --
  1784 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  1785 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  1786 
  1787 * Various options that affect pretty printing etc. are now properly
  1788 handled within the context via configuration options, instead of
  1789 unsynchronized references or print modes.  There are both ML Config.T
  1790 entities and Isar declaration attributes to access these.
  1791 
  1792   ML (Config.T)                 Isar (attribute)
  1793 
  1794   eta_contract                  eta_contract
  1795   show_brackets                 show_brackets
  1796   show_sorts                    show_sorts
  1797   show_types                    show_types
  1798   show_question_marks           show_question_marks
  1799   show_consts                   show_consts
  1800   show_abbrevs                  show_abbrevs
  1801 
  1802   Syntax.ast_trace              syntax_ast_trace
  1803   Syntax.ast_stat               syntax_ast_stat
  1804   Syntax.ambiguity_level        syntax_ambiguity_level
  1805 
  1806   Goal_Display.goals_limit      goals_limit
  1807   Goal_Display.show_main_goal   show_main_goal
  1808 
  1809   Method.rule_trace             rule_trace
  1810 
  1811   Thy_Output.display            thy_output_display
  1812   Thy_Output.quotes             thy_output_quotes
  1813   Thy_Output.indent             thy_output_indent
  1814   Thy_Output.source             thy_output_source
  1815   Thy_Output.break              thy_output_break
  1816 
  1817 Note that corresponding "..._default" references in ML may only be
  1818 changed globally at the ROOT session setup, but *not* within a theory.
  1819 The option "show_abbrevs" supersedes the former print mode
  1820 "no_abbrevs" with inverted meaning.
  1821 
  1822 * More systematic naming of some configuration options.
  1823 INCOMPATIBILITY.
  1824 
  1825   trace_simp  ~>  simp_trace
  1826   debug_simp  ~>  simp_debug
  1827 
  1828 * Support for real valued configuration options, using simplistic
  1829 floating-point notation that coincides with the inner syntax for
  1830 float_token.
  1831 
  1832 * Support for real valued preferences (with approximative PGIP type):
  1833 front-ends need to accept "pgint" values in float notation.
  1834 INCOMPATIBILITY.
  1835 
  1836 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  1837 DejaVu Sans.
  1838 
  1839 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  1840 
  1841 
  1842 *** Pure ***
  1843 
  1844 * Command 'type_synonym' (with single argument) replaces somewhat
  1845 outdated 'types', which is still available as legacy feature for some
  1846 time.
  1847 
  1848 * Command 'nonterminal' (with 'and' separated list of arguments)
  1849 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  1850 
  1851 * Command 'notepad' replaces former 'example_proof' for
  1852 experimentation in Isar without any result.  INCOMPATIBILITY.
  1853 
  1854 * Locale interpretation commands 'interpret' and 'sublocale' accept
  1855 lists of equations to map definitions in a locale to appropriate
  1856 entities in the context of the interpretation.  The 'interpretation'
  1857 command already provided this functionality.
  1858 
  1859 * Diagnostic command 'print_dependencies' prints the locale instances
  1860 that would be activated if the specified expression was interpreted in
  1861 the current context.  Variant "print_dependencies!" assumes a context
  1862 without interpretations.
  1863 
  1864 * Diagnostic command 'print_interps' prints interpretations in proofs
  1865 in addition to interpretations in theories.
  1866 
  1867 * Discontinued obsolete 'global' and 'local' commands to manipulate
  1868 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  1869 Sign.root_path and Sign.local_path may be applied directly where this
  1870 feature is still required for historical reasons.
  1871 
  1872 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  1873 'definition' instead.
  1874 
  1875 * The "prems" fact, which refers to the accidental collection of
  1876 foundational premises in the context, is now explicitly marked as
  1877 legacy feature and will be discontinued soon.  Consider using "assms"
  1878 of the head statement or reference facts by explicit names.
  1879 
  1880 * Document antiquotations @{class} and @{type} print classes and type
  1881 constructors.
  1882 
  1883 * Document antiquotation @{file} checks file/directory entries within
  1884 the local file system.
  1885 
  1886 
  1887 *** HOL ***
  1888 
  1889 * Coercive subtyping: functions can be declared as coercions and type
  1890 inference will add them as necessary upon input of a term.  Theory
  1891 Complex_Main declares real :: nat => real and real :: int => real as
  1892 coercions. A coercion function f is declared like this:
  1893 
  1894   declare [[coercion f]]
  1895 
  1896 To lift coercions through type constructors (e.g. from nat => real to
  1897 nat list => real list), map functions can be declared, e.g.
  1898 
  1899   declare [[coercion_map map]]
  1900 
  1901 Currently coercion inference is activated only in theories including
  1902 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1903 the configuration option "coercion_enabled", e.g. it can be enabled in
  1904 other theories like this:
  1905 
  1906   declare [[coercion_enabled]]
  1907 
  1908 * Command 'partial_function' provides basic support for recursive
  1909 function definitions over complete partial orders.  Concrete instances
  1910 are provided for i) the option type, ii) tail recursion on arbitrary
  1911 types, and iii) the heap monad of Imperative_HOL.  See
  1912 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1913 for examples.
  1914 
  1915 * Function package: f.psimps rules are no longer implicitly declared
  1916 as [simp].  INCOMPATIBILITY.
  1917 
  1918 * Datatype package: theorems generated for executable equality (class
  1919 "eq") carry proper names and are treated as default code equations.
  1920 
  1921 * Inductive package: now offers command 'inductive_simps' to
  1922 automatically derive instantiated and simplified equations for
  1923 inductive predicates, similar to 'inductive_cases'.
  1924 
  1925 * Command 'enriched_type' allows to register properties of the
  1926 functorial structure of types.
  1927 
  1928 * Improved infrastructure for term evaluation using code generator
  1929 techniques, in particular static evaluation conversions.
  1930 
  1931 * Code generator: Scala (2.8 or higher) has been added to the target
  1932 languages.
  1933 
  1934 * Code generator: globbing constant expressions "*" and "Theory.*"
  1935 have been replaced by the more idiomatic "_" and "Theory._".
  1936 INCOMPATIBILITY.
  1937 
  1938 * Code generator: export_code without explicit file declaration prints
  1939 to standard output.  INCOMPATIBILITY.
  1940 
  1941 * Code generator: do not print function definitions for case
  1942 combinators any longer.
  1943 
  1944 * Code generator: simplification with rules determined with
  1945 src/Tools/Code/code_simp.ML and method "code_simp".
  1946 
  1947 * Code generator for records: more idiomatic representation of record
  1948 types.  Warning: records are not covered by ancient SML code
  1949 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1950 rep_datatype declaration helps to succeed then:
  1951 
  1952   record 'a foo = ...
  1953   ...
  1954   rep_datatype foo_ext ...
  1955 
  1956 * Records: logical foundation type for records does not carry a
  1957 '_type' suffix any longer (obsolete due to authentic syntax).
  1958 INCOMPATIBILITY.
  1959 
  1960 * Quickcheck now by default uses exhaustive testing instead of random
  1961 testing.  Random testing can be invoked by "quickcheck [random]",
  1962 exhaustive testing by "quickcheck [exhaustive]".
  1963 
  1964 * Quickcheck instantiates polymorphic types with small finite
  1965 datatypes by default. This enables a simple execution mechanism to
  1966 handle quantifiers and function equality over the finite datatypes.
  1967 
  1968 * Quickcheck random generator has been renamed from "code" to
  1969 "random".  INCOMPATIBILITY.
  1970 
  1971 * Quickcheck now has a configurable time limit which is set to 30
  1972 seconds by default. This can be changed by adding [timeout = n] to the
  1973 quickcheck command. The time limit for Auto Quickcheck is still set
  1974 independently.
  1975 
  1976 * Quickcheck in locales considers interpretations of that locale for
  1977 counter example search.
  1978 
  1979 * Sledgehammer:
  1980   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1981     method. See the Sledgehammer manual for details ("isabelle doc
  1982     sledgehammer").
  1983   - Renamed commands:
  1984     sledgehammer atp_info ~> sledgehammer running_provers
  1985     sledgehammer atp_kill ~> sledgehammer kill_provers
  1986     sledgehammer available_atps ~> sledgehammer available_provers
  1987     INCOMPATIBILITY.
  1988   - Renamed options:
  1989     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1990     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1991     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1992     (and "ms" and "min" are no longer supported)
  1993     INCOMPATIBILITY.
  1994 
  1995 * Nitpick:
  1996   - Renamed options:
  1997     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1998     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1999     INCOMPATIBILITY.
  2000   - Added support for partial quotient types.
  2001   - Added local versions of the "Nitpick.register_xxx" functions.
  2002   - Added "whack" option.
  2003   - Allow registration of quotient types as codatatypes.
  2004   - Improved "merge_type_vars" option to merge more types.
  2005   - Removed unsound "fast_descrs" option.
  2006   - Added custom symmetry breaking for datatypes, making it possible to reach
  2007     higher cardinalities.
  2008   - Prevent the expansion of too large definitions.
  2009 
  2010 * Proof methods "metis" and "meson" now have configuration options
  2011 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  2012 to diagnose these tools. E.g.
  2013 
  2014     using [[metis_trace = true]]
  2015 
  2016 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  2017 manually as command 'solve_direct'.
  2018 
  2019 * The default SMT solver Z3 must be enabled explicitly (due to
  2020 licensing issues) by setting the environment variable
  2021 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  2022 commercial applications, the SMT solver CVC3 is provided as fall-back;
  2023 changing the SMT solver is done via the configuration option
  2024 "smt_solver".
  2025 
  2026 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  2027 i.e. "remote_cvc3" and "remote_z3".
  2028 
  2029 * Added basic SMT support for datatypes, records, and typedefs using
  2030 the oracle mode (no proofs).  Direct support of pairs has been dropped
  2031 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  2032 support for a similar behavior).  Minor INCOMPATIBILITY.
  2033 
  2034 * Changed SMT configuration options:
  2035   - Renamed:
  2036     z3_proofs ~> smt_oracle (with inverted meaning)
  2037     z3_trace_assms ~> smt_trace_used_facts
  2038     INCOMPATIBILITY.
  2039   - Added:
  2040     smt_verbose
  2041     smt_random_seed
  2042     smt_datatypes
  2043     smt_infer_triggers
  2044     smt_monomorph_limit
  2045     cvc3_options
  2046     remote_cvc3_options
  2047     remote_z3_options
  2048     yices_options
  2049 
  2050 * Boogie output files (.b2i files) need to be declared in the theory
  2051 header.
  2052 
  2053 * Simplification procedure "list_to_set_comprehension" rewrites list
  2054 comprehensions applied to List.set to set comprehensions.  Occasional
  2055 INCOMPATIBILITY, may be deactivated like this:
  2056 
  2057   declare [[simproc del: list_to_set_comprehension]]
  2058 
  2059 * Removed old version of primrec package.  INCOMPATIBILITY.
  2060 
  2061 * Removed simplifier congruence rule of "prod_case", as has for long
  2062 been the case with "split".  INCOMPATIBILITY.
  2063 
  2064 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  2065 
  2066 * Removed [split_format ... and ... and ...] version of
  2067 [split_format].  Potential INCOMPATIBILITY.
  2068 
  2069 * Predicate "sorted" now defined inductively, with nice induction
  2070 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  2071 
  2072 * Constant "contents" renamed to "the_elem", to free the generic name
  2073 contents for other uses.  INCOMPATIBILITY.
  2074 
  2075 * Renamed class eq and constant eq (for code generation) to class
  2076 equal and constant equal, plus renaming of related facts and various
  2077 tuning.  INCOMPATIBILITY.
  2078 
  2079 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  2080 
  2081 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  2082 INCOMPATIBILITY.
  2083 
  2084 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  2085 avoid confusion with finite sets.  INCOMPATIBILITY.
  2086 
  2087 * Abandoned locales equiv, congruent and congruent2 for equivalence
  2088 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  2089 for congruent(2)).
  2090 
  2091 * Some previously unqualified names have been qualified:
  2092 
  2093   types
  2094     bool ~> HOL.bool
  2095     nat ~> Nat.nat
  2096 
  2097   constants
  2098     Trueprop ~> HOL.Trueprop
  2099     True ~> HOL.True
  2100     False ~> HOL.False
  2101     op & ~> HOL.conj
  2102     op | ~> HOL.disj
  2103     op --> ~> HOL.implies
  2104     op = ~> HOL.eq
  2105     Not ~> HOL.Not
  2106     The ~> HOL.The
  2107     All ~> HOL.All
  2108     Ex ~> HOL.Ex
  2109     Ex1 ~> HOL.Ex1
  2110     Let ~> HOL.Let
  2111     If ~> HOL.If
  2112     Ball ~> Set.Ball
  2113     Bex ~> Set.Bex
  2114     Suc ~> Nat.Suc
  2115     Pair ~> Product_Type.Pair
  2116     fst ~> Product_Type.fst
  2117     snd ~> Product_Type.snd
  2118     curry ~> Product_Type.curry
  2119     op : ~> Set.member
  2120     Collect ~> Set.Collect
  2121 
  2122 INCOMPATIBILITY.
  2123 
  2124 * More canonical naming convention for some fundamental definitions:
  2125 
  2126     bot_bool_eq ~> bot_bool_def
  2127     top_bool_eq ~> top_bool_def
  2128     inf_bool_eq ~> inf_bool_def
  2129     sup_bool_eq ~> sup_bool_def
  2130     bot_fun_eq  ~> bot_fun_def
  2131     top_fun_eq  ~> top_fun_def
  2132     inf_fun_eq  ~> inf_fun_def
  2133     sup_fun_eq  ~> sup_fun_def
  2134 
  2135 INCOMPATIBILITY.
  2136 
  2137 * More stylized fact names:
  2138 
  2139   expand_fun_eq ~> fun_eq_iff
  2140   expand_set_eq ~> set_eq_iff
  2141   set_ext       ~> set_eqI
  2142   nat_number    ~> eval_nat_numeral
  2143 
  2144 INCOMPATIBILITY.
  2145 
  2146 * Refactoring of code-generation specific operations in theory List:
  2147 
  2148   constants
  2149     null ~> List.null
  2150 
  2151   facts
  2152     mem_iff ~> member_def
  2153     null_empty ~> null_def
  2154 
  2155 INCOMPATIBILITY.  Note that these were not supposed to be used
  2156 regularly unless for striking reasons; their main purpose was code
  2157 generation.
  2158 
  2159 Various operations from the Haskell prelude are used for generating
  2160 Haskell code.
  2161 
  2162 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  2163 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  2164 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  2165 
  2166 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  2167 "*" and "+" respectively.  INCOMPATIBILITY.
  2168 
  2169 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  2170 "Sum_Type.Plus" instead.
  2171 
  2172 * Constant "split" has been merged with constant "prod_case"; names of
  2173 ML functions, facts etc. involving split have been retained so far,
  2174 though.  INCOMPATIBILITY.
  2175 
  2176 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  2177 instead.  INCOMPATIBILITY.
  2178 
  2179 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  2180 INCOMPATIBILITY.
  2181 
  2182 * Former theory Library/Enum is now part of the HOL-Main image.
  2183 INCOMPATIBILITY: all constants of the Enum theory now have to be
  2184 referred to by its qualified name.
  2185 
  2186   enum    ~>  Enum.enum
  2187   nlists  ~>  Enum.nlists
  2188   product ~>  Enum.product
  2189 
  2190 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  2191 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  2192 INCOMPATIBILITY.
  2193 
  2194 * Theory Library/SetsAndFunctions has been split into
  2195 Library/Function_Algebras and Library/Set_Algebras; canonical names
  2196 for instance definitions for functions; various improvements.
  2197 INCOMPATIBILITY.
  2198 
  2199 * Theory Library/Multiset provides stable quicksort implementation of
  2200 sort_key.
  2201 
  2202 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  2203 INCOMPATIBILITY.
  2204 
  2205 * Session Multivariate_Analysis: introduced a type class for euclidean
  2206 space.  Most theorems are now stated in terms of euclidean spaces
  2207 instead of finite cartesian products.
  2208 
  2209   types
  2210     real ^ 'n ~>  'a::real_vector
  2211               ~>  'a::euclidean_space
  2212               ~>  'a::ordered_euclidean_space
  2213         (depends on your needs)
  2214 
  2215   constants
  2216      _ $ _        ~> _ $$ _
  2217      \<chi> x. _  ~> \<chi>\<chi> x. _
  2218      CARD('n)     ~> DIM('a)
  2219 
  2220 Also note that the indices are now natural numbers and not from some
  2221 finite type. Finite cartesian products of euclidean spaces, products
  2222 of euclidean spaces the real and complex numbers are instantiated to
  2223 be euclidean_spaces.  INCOMPATIBILITY.
  2224 
  2225 * Session Probability: introduced pextreal as positive extended real
  2226 numbers.  Use pextreal as value for measures.  Introduce the
  2227 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  2228 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  2229 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  2230 
  2231 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  2232 INCOMPATIBILITY.
  2233 
  2234 * Session SPARK (with image HOL-SPARK) provides commands to load and
  2235 prove verification conditions generated by the SPARK Ada program
  2236 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  2237 
  2238 
  2239 *** HOL-Algebra ***
  2240 
  2241 * Theorems for additive ring operations (locale abelian_monoid and
  2242 descendants) are generated by interpretation from their multiplicative
  2243 counterparts.  Names (in particular theorem names) have the mandatory
  2244 qualifier 'add'.  Previous theorem names are redeclared for
  2245 compatibility.
  2246 
  2247 * Structure "int_ring" is now an abbreviation (previously a
  2248 definition).  This fits more natural with advanced interpretations.
  2249 
  2250 
  2251 *** HOLCF ***
  2252 
  2253 * The domain package now runs in definitional mode by default: The
  2254 former command 'new_domain' is now called 'domain'.  To use the domain
  2255 package in its original axiomatic mode, use 'domain (unsafe)'.
  2256 INCOMPATIBILITY.
  2257 
  2258 * The new class "domain" is now the default sort.  Class "predomain"
  2259 is an unpointed version of "domain". Theories can be updated by
  2260 replacing sort annotations as shown below.  INCOMPATIBILITY.
  2261 
  2262   'a::type ~> 'a::countable
  2263   'a::cpo  ~> 'a::predomain
  2264   'a::pcpo ~> 'a::domain
  2265 
  2266 * The old type class "rep" has been superseded by class "domain".
  2267 Accordingly, users of the definitional package must remove any
  2268 "default_sort rep" declarations.  INCOMPATIBILITY.
  2269 
  2270 * The domain package (definitional mode) now supports unpointed
  2271 predomain argument types, as long as they are marked 'lazy'. (Strict
  2272 arguments must be in class "domain".) For example, the following
  2273 domain definition now works:
  2274 
  2275   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  2276 
  2277 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  2278 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  2279 'a option, and 'a list.  Additionally, it configures fixrec and the
  2280 domain package to work with these types.  For example:
  2281 
  2282   fixrec isInl :: "('a + 'b) u -> tr"
  2283     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  2284 
  2285   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  2286 
  2287 * The "(permissive)" option of fixrec has been replaced with a
  2288 per-equation "(unchecked)" option. See
  2289 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  2290 
  2291 * The "bifinite" class no longer fixes a constant "approx"; the class
  2292 now just asserts that such a function exists.  INCOMPATIBILITY.
  2293 
  2294 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  2295 defines an embedding of type 'a defl into udom by default; instances
  2296 of "bifinite" and "domain" classes are available in
  2297 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  2298 
  2299 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  2300 
  2301 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  2302 
  2303 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  2304 
  2305 * The function "cprod_map" has been renamed to "prod_map".
  2306 INCOMPATIBILITY.
  2307 
  2308 * The monadic bind operator on each powerdomain has new binder syntax
  2309 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  2310 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  2311 
  2312 * The infix syntax for binary union on each powerdomain has changed
  2313 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  2314 syntax.  INCOMPATIBILITY.
  2315 
  2316 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  2317 still supported as an input translation.
  2318 
  2319 * Renamed some theorems (the original names are also still available).
  2320 
  2321   expand_fun_below   ~> fun_below_iff
  2322   below_fun_ext      ~> fun_belowI
  2323   expand_cfun_eq     ~> cfun_eq_iff
  2324   ext_cfun           ~> cfun_eqI
  2325   expand_cfun_below  ~> cfun_below_iff
  2326   below_cfun_ext     ~> cfun_belowI
  2327   cont2cont_Rep_CFun ~> cont2cont_APP
  2328 
  2329 * The Abs and Rep functions for various types have changed names.
  2330 Related theorem names have also changed to match. INCOMPATIBILITY.
  2331 
  2332   Rep_CFun  ~> Rep_cfun
  2333   Abs_CFun  ~> Abs_cfun
  2334   Rep_Sprod ~> Rep_sprod
  2335   Abs_Sprod ~> Abs_sprod
  2336   Rep_Ssum  ~> Rep_ssum
  2337   Abs_Ssum  ~> Abs_ssum
  2338 
  2339 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  2340 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  2341 
  2342 * Various changes to bisimulation/coinduction with domain package:
  2343 
  2344   - Definitions of "bisim" constants no longer mention definedness.
  2345   - With mutual recursion, "bisim" predicate is now curried.
  2346   - With mutual recursion, each type gets a separate coind theorem.
  2347   - Variable names in bisim_def and coinduct rules have changed.
  2348 
  2349 INCOMPATIBILITY.
  2350 
  2351 * Case combinators generated by the domain package for type "foo" are
  2352 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  2353 
  2354 * Several theorems have been renamed to more accurately reflect the
  2355 names of constants and types involved.  INCOMPATIBILITY.
  2356 
  2357   thelub_const    ~> lub_const
  2358   lub_const       ~> is_lub_const
  2359   thelubI         ~> lub_eqI
  2360   is_lub_lub      ~> is_lubD2
  2361   lubI            ~> is_lub_lub
  2362   unique_lub      ~> is_lub_unique
  2363   is_ub_lub       ~> is_lub_rangeD1
  2364   lub_bin_chain   ~> is_lub_bin_chain
  2365   lub_fun         ~> is_lub_fun
  2366   thelub_fun      ~> lub_fun
  2367   thelub_cfun     ~> lub_cfun
  2368   thelub_Pair     ~> lub_Pair
  2369   lub_cprod       ~> is_lub_prod
  2370   thelub_cprod    ~> lub_prod
  2371   minimal_cprod   ~> minimal_prod
  2372   inst_cprod_pcpo ~> inst_prod_pcpo
  2373   UU_I            ~> bottomI
  2374   compact_UU      ~> compact_bottom
  2375   deflation_UU    ~> deflation_bottom
  2376   finite_deflation_UU ~> finite_deflation_bottom
  2377 
  2378 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  2379 
  2380   sq_ord_less_eq_trans ~> below_eq_trans
  2381   sq_ord_eq_less_trans ~> eq_below_trans
  2382   refl_less            ~> below_refl
  2383   trans_less           ~> below_trans
  2384   antisym_less         ~> below_antisym
  2385   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  2386   box_less             ~> box_below
  2387   rev_trans_less       ~> rev_below_trans
  2388   not_less2not_eq      ~> not_below2not_eq
  2389   less_UU_iff          ~> below_UU_iff
  2390   flat_less_iff        ~> flat_below_iff
  2391   adm_less             ~> adm_below
  2392   adm_not_less         ~> adm_not_below
  2393   adm_compact_not_less ~> adm_compact_not_below
  2394   less_fun_def         ~> below_fun_def
  2395   expand_fun_less      ~> fun_below_iff
  2396   less_fun_ext         ~> fun_belowI
  2397   less_discr_def       ~> below_discr_def
  2398   discr_less_eq        ~> discr_below_eq
  2399   less_unit_def        ~> below_unit_def
  2400   less_cprod_def       ~> below_prod_def
  2401   prod_lessI           ~> prod_belowI
  2402   Pair_less_iff        ~> Pair_below_iff
  2403   fst_less_iff         ~> fst_below_iff
  2404   snd_less_iff         ~> snd_below_iff
  2405   expand_cfun_less     ~> cfun_below_iff
  2406   less_cfun_ext        ~> cfun_belowI
  2407   injection_less       ~> injection_below
  2408   less_up_def          ~> below_up_def
  2409   not_Iup_less         ~> not_Iup_below
  2410   Iup_less             ~> Iup_below
  2411   up_less              ~> up_below
  2412   Def_inject_less_eq   ~> Def_below_Def
  2413   Def_less_is_eq       ~> Def_below_iff
  2414   spair_less_iff       ~> spair_below_iff
  2415   less_sprod           ~> below_sprod
  2416   spair_less           ~> spair_below
  2417   sfst_less_iff        ~> sfst_below_iff
  2418   ssnd_less_iff        ~> ssnd_below_iff
  2419   fix_least_less       ~> fix_least_below
  2420   dist_less_one        ~> dist_below_one
  2421   less_ONE             ~> below_ONE
  2422   ONE_less_iff         ~> ONE_below_iff
  2423   less_sinlD           ~> below_sinlD
  2424   less_sinrD           ~> below_sinrD
  2425 
  2426 
  2427 *** FOL and ZF ***
  2428 
  2429 * All constant names are now qualified internally and use proper
  2430 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  2431 
  2432 
  2433 *** ML ***
  2434 
  2435 * Antiquotation @{assert} inlines a function bool -> unit that raises
  2436 Fail if the argument is false.  Due to inlining the source position of
  2437 failed assertions is included in the error output.
  2438 
  2439 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  2440 text is in practice always evaluated with a stable theory checkpoint.
  2441 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  2442 
  2443 * Antiquotation @{theory A} refers to theory A from the ancestry of
  2444 the current context, not any accidental theory loader state as before.
  2445 Potential INCOMPATIBILITY, subtle change in semantics.
  2446 
  2447 * Syntax.pretty_priority (default 0) configures the required priority
  2448 of pretty-printed output and thus affects insertion of parentheses.
  2449 
  2450 * Syntax.default_root (default "any") configures the inner syntax
  2451 category (nonterminal symbol) for parsing of terms.
  2452 
  2453 * Former exception Library.UnequalLengths now coincides with
  2454 ListPair.UnequalLengths.
  2455 
  2456 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  2457 main functionality is provided by structure Simplifier.
  2458 
  2459 * Renamed raw "explode" function to "raw_explode" to emphasize its
  2460 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  2461 almost all situations.
  2462 
  2463 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  2464 See implementation manual for further details on exceptions in
  2465 Isabelle/ML.
  2466 
  2467 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  2468 meaning.
  2469 
  2470 * Renamed structure PureThy to Pure_Thy and moved most of its
  2471 operations to structure Global_Theory, to emphasize that this is
  2472 rarely-used global-only stuff.
  2473 
  2474 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  2475 instead (or tracing for high-volume output).
  2476 
  2477 * Configuration option show_question_marks only affects regular pretty
  2478 printing of types and terms, not raw Term.string_of_vname.
  2479 
  2480 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  2481 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  2482 @{thms} for most purposes.
  2483 
  2484 * ML structure Unsynchronized is never opened, not even in Isar
  2485 interaction mode as before.  Old Unsynchronized.set etc. have been
  2486 discontinued -- use plain := instead.  This should be *rare* anyway,
  2487 since modern tools always work via official context data, notably
  2488 configuration options.
  2489 
  2490 * Parallel and asynchronous execution requires special care concerning
  2491 interrupts.  Structure Exn provides some convenience functions that
  2492 avoid working directly with raw Interrupt.  User code must not absorb
  2493 interrupts -- intermediate handling (for cleanup etc.) needs to be
  2494 followed by re-raising of the original exception.  Another common
  2495 source of mistakes are "handle _" patterns, which make the meaning of
  2496 the program subject to physical effects of the environment.
  2497 
  2498 
  2499 
  2500 New in Isabelle2009-2 (June 2010)
  2501 ---------------------------------
  2502 
  2503 *** General ***
  2504 
  2505 * Authentic syntax for *all* logical entities (type classes, type
  2506 constructors, term constants): provides simple and robust
  2507 correspondence between formal entities and concrete syntax.  Within
  2508 the parse tree / AST representations, "constants" are decorated by
  2509 their category (class, type, const) and spelled out explicitly with
  2510 their full internal name.
  2511 
  2512 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  2513 and translations (translation rules and translation functions in ML).
  2514 Some hints on upgrading:
  2515 
  2516   - Many existing uses of 'syntax' and 'translations' can be replaced
  2517     by more modern 'type_notation', 'notation' and 'abbreviation',
  2518     which are independent of this issue.
  2519 
  2520   - 'translations' require markup within the AST; the term syntax
  2521     provides the following special forms:
  2522 
  2523       CONST c   -- produces syntax version of constant c from context
  2524       XCONST c  -- literally c, checked as constant from context
  2525       c         -- literally c, if declared by 'syntax'
  2526 
  2527     Plain identifiers are treated as AST variables -- occasionally the
  2528     system indicates accidental variables via the error "rhs contains
  2529     extra variables".
  2530 
  2531     Type classes and type constructors are marked according to their
  2532     concrete syntax.  Some old translations rules need to be written
  2533     for the "type" category, using type constructor application
  2534     instead of pseudo-term application of the default category
  2535     "logic".
  2536 
  2537   - 'parse_translation' etc. in ML may use the following
  2538     antiquotations:
  2539 
  2540       @{class_syntax c}   -- type class c within parse tree / AST
  2541       @{term_syntax c}    -- type constructor c within parse tree / AST
  2542       @{const_syntax c}   -- ML version of "CONST c" above
  2543       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  2544 
  2545   - Literal types within 'typed_print_translations', i.e. those *not*
  2546     represented as pseudo-terms are represented verbatim.  Use @{class
  2547     c} or @{type_name c} here instead of the above syntax
  2548     antiquotations.
  2549 
  2550 Note that old non-authentic syntax was based on unqualified base
  2551 names, so all of the above "constant" names would coincide.  Recall
  2552 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  2553 diagnose syntax problems.
  2554 
  2555 * Type constructors admit general mixfix syntax, not just infix.
  2556 
  2557 * Concrete syntax may be attached to local entities without a proof
  2558 body, too.  This works via regular mixfix annotations for 'fix',
  2559 'def', 'obtain' etc. or via the explicit 'write' command, which is
  2560 similar to the 'notation' command in theory specifications.
  2561 
  2562 * Discontinued unnamed infix syntax (legacy feature for many years) --
  2563 need to specify constant name and syntax separately.  Internal ML
  2564 datatype constructors have been renamed from InfixName to Infix etc.
  2565 Minor INCOMPATIBILITY.
  2566 
  2567 * Schematic theorem statements need to be explicitly markup as such,
  2568 via commands 'schematic_lemma', 'schematic_theorem',
  2569 'schematic_corollary'.  Thus the relevance of the proof is made
  2570 syntactically clear, which impacts performance in a parallel or
  2571 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  2572 
  2573 * Use of cumulative prems via "!" in some proof methods has been
  2574 discontinued (old legacy feature).
  2575 
  2576 * References 'trace_simp' and 'debug_simp' have been replaced by
  2577 configuration options stored in the context. Enabling tracing (the
  2578 case of debugging is similar) in proofs works via
  2579 
  2580   using [[trace_simp = true]]
  2581 
  2582 Tracing is then active for all invocations of the simplifier in
  2583 subsequent goal refinement steps. Tracing may also still be enabled or
  2584 disabled via the ProofGeneral settings menu.
  2585 
  2586 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  2587 'hide_fact' replace the former 'hide' KIND command.  Minor
  2588 INCOMPATIBILITY.
  2589 
  2590 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  2591 more efficient than combinations with -q1 or -q2.
  2592 
  2593 
  2594 *** Pure ***
  2595 
  2596 * Proofterms record type-class reasoning explicitly, using the
  2597 "unconstrain" operation internally.  This eliminates all sort
  2598 constraints from a theorem and proof, introducing explicit
  2599 OFCLASS-premises.  On the proof term level, this operation is
  2600 automatically applied at theorem boundaries, such that closed proofs
  2601 are always free of sort constraints.  INCOMPATIBILITY for tools that
  2602 inspect proof terms.
  2603 
  2604 * Local theory specifications may depend on extra type variables that
  2605 are not present in the result type -- arguments TYPE('a) :: 'a itself
  2606 are added internally.  For example:
  2607 
  2608   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  2609 
  2610 * Predicates of locales introduced by classes carry a mandatory
  2611 "class" prefix.  INCOMPATIBILITY.
  2612 
  2613 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  2614 
  2615 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  2616 'class' instead.
  2617 
  2618 * Command 'code_reflect' allows to incorporate generated ML code into
  2619 runtime environment; replaces immature code_datatype antiquotation.
  2620 INCOMPATIBILITY.
  2621 
  2622 * Code generator: simple concept for abstract datatypes obeying
  2623 invariants.
  2624 
  2625 * Code generator: details of internal data cache have no impact on the
  2626 user space functionality any longer.
  2627 
  2628 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  2629 subgoals.  This is more appropriate for interpretations with 'where'.
  2630 INCOMPATIBILITY.
  2631 
  2632 * Command 'example_proof' opens an empty proof body.  This allows to
  2633 experiment with Isar, without producing any persistent result.
  2634 
  2635 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  2636 within a local theory context, with explicit checking of the
  2637 constructors involved (in contrast to the raw 'syntax' versions).
  2638 
  2639 * Commands 'types' and 'typedecl' now work within a local theory
  2640 context -- without introducing dependencies on parameters or
  2641 assumptions, which is not possible in Isabelle/Pure.
  2642 
  2643 * Command 'defaultsort' has been renamed to 'default_sort', it works
  2644 within a local theory context.  Minor INCOMPATIBILITY.
  2645 
  2646 
  2647 *** HOL ***
  2648 
  2649 * Command 'typedef' now works within a local theory context -- without
  2650 introducing dependencies on parameters or assumptions, which is not
  2651 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  2652 contain multiple interpretations of local typedefs (with different
  2653 non-emptiness proofs), even in a global theory context.
  2654 
  2655 * New package for quotient types.  Commands 'quotient_type' and
  2656 'quotient_definition' may be used for defining types and constants by
  2657 quotient constructions.  An example is the type of integers created by
  2658 quotienting pairs of natural numbers:
  2659 
  2660   fun
  2661     intrel :: "(nat * nat) => (nat * nat) => bool"
  2662   where
  2663     "intrel (x, y) (u, v) = (x + v = u + y)"
  2664 
  2665   quotient_type int = "nat * nat" / intrel
  2666     by (auto simp add: equivp_def expand_fun_eq)
  2667 
  2668   quotient_definition
  2669     "0::int" is "(0::nat, 0::nat)"
  2670 
  2671 The method "lifting" can be used to lift of theorems from the
  2672 underlying "raw" type to the quotient type.  The example
  2673 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  2674 construction and provides a reasoning infrastructure for finite sets.
  2675 
  2676 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  2677 clash with new theory Quotient in Main HOL.
  2678 
  2679 * Moved the SMT binding into the main HOL session, eliminating
  2680 separate HOL-SMT session.
  2681 
  2682 * List membership infix mem operation is only an input abbreviation.
  2683 INCOMPATIBILITY.
  2684 
  2685 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  2686 for future developements; former Library/Word.thy is still present in
  2687 the AFP entry RSAPPS.
  2688 
  2689 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  2690 longer shadowed.  INCOMPATIBILITY.
  2691 
  2692 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  2693 INCOMPATIBILITY.
  2694 
  2695 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  2696 INCOMPATIBILITY.
  2697 
  2698 * Dropped normalizing_semiring etc; use the facts in semiring classes
  2699 instead.  INCOMPATIBILITY.
  2700 
  2701 * Dropped several real-specific versions of lemmas about floor and
  2702 ceiling; use the generic lemmas from theory "Archimedean_Field"
  2703 instead.  INCOMPATIBILITY.
  2704 
  2705   floor_number_of_eq         ~> floor_number_of
  2706   le_floor_eq_number_of      ~> number_of_le_floor
  2707   le_floor_eq_zero           ~> zero_le_floor
  2708   le_floor_eq_one            ~> one_le_floor
  2709   floor_less_eq_number_of    ~> floor_less_number_of
  2710   floor_less_eq_zero         ~> floor_less_zero
  2711   floor_less_eq_one          ~> floor_less_one
  2712   less_floor_eq_number_of    ~> number_of_less_floor
  2713   less_floor_eq_zero         ~> zero_less_floor
  2714   less_floor_eq_one          ~> one_less_floor
  2715   floor_le_eq_number_of      ~> floor_le_number_of
  2716   floor_le_eq_zero           ~> floor_le_zero
  2717   floor_le_eq_one            ~> floor_le_one
  2718   floor_subtract_number_of   ~> floor_diff_number_of
  2719   floor_subtract_one         ~> floor_diff_one
  2720   ceiling_number_of_eq       ~> ceiling_number_of
  2721   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  2722   ceiling_le_zero_eq         ~> ceiling_le_zero
  2723   ceiling_le_eq_one          ~> ceiling_le_one
  2724   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  2725   less_ceiling_eq_zero       ~> zero_less_ceiling
  2726   less_ceiling_eq_one        ~> one_less_ceiling
  2727   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  2728   ceiling_less_eq_zero       ~> ceiling_less_zero
  2729   ceiling_less_eq_one        ~> ceiling_less_one
  2730   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  2731   le_ceiling_eq_zero         ~> zero_le_ceiling
  2732   le_ceiling_eq_one          ~> one_le_ceiling
  2733   ceiling_subtract_number_of ~> ceiling_diff_number_of
  2734   ceiling_subtract_one       ~> ceiling_diff_one
  2735 
  2736 * Theory "Finite_Set": various folding_XXX locales facilitate the
  2737 application of the various fold combinators on finite sets.
  2738 
  2739 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  2740 provides abstract red-black tree type which is backed by "RBT_Impl" as
  2741 implementation.  INCOMPATIBILTY.
  2742 
  2743 * Theory Library/Coinductive_List has been removed -- superseded by
  2744 AFP/thys/Coinductive.
  2745 
  2746 * Theory PReal, including the type "preal" and related operations, has
  2747 been removed.  INCOMPATIBILITY.
  2748 
  2749 * Real: new development using Cauchy Sequences.
  2750 
  2751 * Split off theory "Big_Operators" containing setsum, setprod,
  2752 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  2753 
  2754 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  2755 "Int" etc.  INCOMPATIBILITY.
  2756 
  2757 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  2758 
  2759 * New set of rules "ac_simps" provides combined assoc / commute
  2760 rewrites for all interpretations of the appropriate generic locales.
  2761 
  2762 * Renamed theory "OrderedGroup" to "Groups" and split theory
  2763 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  2764 appropriate and more consistent names suitable for name prefixes
  2765 within the HOL theories.  INCOMPATIBILITY.
  2766 
  2767 * Some generic constants have been put to appropriate theories:
  2768   - less_eq, less: Orderings
  2769   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  2770   - inverse, divide: Rings
  2771 INCOMPATIBILITY.
  2772 
  2773 * More consistent naming of type classes involving orderings (and
  2774 lattices):
  2775 
  2776     lower_semilattice                   ~> semilattice_inf
  2777     upper_semilattice                   ~> semilattice_sup
  2778 
  2779     dense_linear_order                  ~> dense_linorder
  2780 
  2781     pordered_ab_group_add               ~> ordered_ab_group_add
  2782     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  2783     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  2784     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  2785     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  2786     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  2787     pordered_cancel_semiring            ~> ordered_cancel_semiring
  2788     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  2789     pordered_comm_ring                  ~> ordered_comm_ring
  2790     pordered_comm_semiring              ~> ordered_comm_semiring
  2791     pordered_ring                       ~> ordered_ring
  2792     pordered_ring_abs                   ~> ordered_ring_abs
  2793     pordered_semiring                   ~> ordered_semiring
  2794 
  2795     ordered_ab_group_add                ~> linordered_ab_group_add
  2796     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  2797     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  2798     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  2799     ordered_field                       ~> linordered_field
  2800     ordered_field_no_lb                 ~> linordered_field_no_lb
  2801     ordered_field_no_ub                 ~> linordered_field_no_ub
  2802     ordered_field_dense_linear_order    ~> dense_linordered_field
  2803     ordered_idom                        ~> linordered_idom
  2804     ordered_ring                        ~> linordered_ring
  2805     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  2806     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  2807     ordered_ring_strict                 ~> linordered_ring_strict
  2808     ordered_semidom                     ~> linordered_semidom
  2809     ordered_semiring                    ~> linordered_semiring
  2810     ordered_semiring_1                  ~> linordered_semiring_1
  2811     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  2812     ordered_semiring_strict             ~> linordered_semiring_strict
  2813 
  2814   The following slightly odd type classes have been moved to a
  2815   separate theory Library/Lattice_Algebras:
  2816 
  2817     lordered_ab_group_add               ~> lattice_ab_group_add
  2818     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  2819     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  2820     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  2821     lordered_ring                       ~> lattice_ring
  2822 
  2823 INCOMPATIBILITY.
  2824 
  2825 * Refined field classes:
  2826   - classes division_ring_inverse_zero, field_inverse_zero,
  2827     linordered_field_inverse_zero include rule inverse 0 = 0 --
  2828     subsumes former division_by_zero class;
  2829   - numerous lemmas have been ported from field to division_ring.
  2830 INCOMPATIBILITY.
  2831 
  2832 * Refined algebra theorem collections:
  2833   - dropped theorem group group_simps, use algebra_simps instead;
  2834   - dropped theorem group ring_simps, use field_simps instead;
  2835   - proper theorem collection field_simps subsumes former theorem
  2836     groups field_eq_simps and field_simps;
  2837   - dropped lemma eq_minus_self_iff which is a duplicate for
  2838     equal_neg_zero.
  2839 INCOMPATIBILITY.
  2840 
  2841 * Theory Finite_Set and List: some lemmas have been generalized from
  2842 sets to lattices:
  2843 
  2844   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  2845   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  2846   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  2847   union_Union_fold_union        ~> sup_Sup_fold_sup
  2848   Inter_fold_inter              ~> Inf_fold_inf
  2849   Union_fold_union              ~> Sup_fold_sup
  2850   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  2851   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  2852   INTER_fold_inter              ~> INFI_fold_inf
  2853   UNION_fold_union              ~> SUPR_fold_sup
  2854 
  2855 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  2856 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  2857 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  2858 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  2859 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  2860 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  2861 
  2862 * Reorganized theory Multiset: swapped notation of pointwise and
  2863 multiset order:
  2864 
  2865   - pointwise ordering is instance of class order with standard syntax
  2866     <= and <;
  2867   - multiset ordering has syntax <=# and <#; partial order properties
  2868     are provided by means of interpretation with prefix
  2869     multiset_order;
  2870   - less duplication, less historical organization of sections,
  2871     conversion from associations lists to multisets, rudimentary code
  2872     generation;
  2873   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  2874     if needed.
  2875 
  2876 Renamed:
  2877 
  2878   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  2879   multi_count_ext  ~>  multiset_ext
  2880   diff_union_inverse2  ~>  diff_union_cancelR
  2881 
  2882 INCOMPATIBILITY.
  2883 
  2884 * Theory Permutation: replaced local "remove" by List.remove1.
  2885 
  2886 * Code generation: ML and OCaml code is decorated with signatures.
  2887 
  2888 * Theory List: added transpose.
  2889 
  2890 * Library/Nat_Bijection.thy is a collection of bijective functions
  2891 between nat and other types, which supersedes the older libraries
  2892 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2893 
  2894   Constants:
  2895   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2896   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2897   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2898   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2899   Countable.pair_encode           ~> prod_encode
  2900   NatIso.prod2nat                 ~> prod_encode
  2901   NatIso.nat2prod                 ~> prod_decode
  2902   NatIso.sum2nat                  ~> sum_encode
  2903   NatIso.nat2sum                  ~> sum_decode
  2904   NatIso.list2nat                 ~> list_encode
  2905   NatIso.nat2list                 ~> list_decode
  2906   NatIso.set2nat                  ~> set_encode
  2907   NatIso.nat2set                  ~> set_decode
  2908 
  2909   Lemmas:
  2910   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2911   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2912   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2913   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2914   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2915   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2916   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2917   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2918   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2919   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2920   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2921   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2922   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2923 
  2924 * Sledgehammer:
  2925   - Renamed ATP commands:
  2926     atp_info     ~> sledgehammer running_atps
  2927     atp_kill     ~> sledgehammer kill_atps
  2928     atp_messages ~> sledgehammer messages
  2929     atp_minimize ~> sledgehammer minimize
  2930     print_atps   ~> sledgehammer available_atps
  2931     INCOMPATIBILITY.
  2932   - Added user's manual ("isabelle doc sledgehammer").
  2933   - Added option syntax and "sledgehammer_params" to customize
  2934     Sledgehammer's behavior.  See the manual for details.
  2935   - Modified the Isar proof reconstruction code so that it produces
  2936     direct proofs rather than proofs by contradiction.  (This feature
  2937     is still experimental.)
  2938   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2939     full-typed mode.
  2940   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2941 
  2942 * Nitpick:
  2943   - Added and implemented "binary_ints" and "bits" options.
  2944   - Added "std" option and implemented support for nonstandard models.
  2945   - Added and implemented "finitize" option to improve the precision
  2946     of infinite datatypes based on a monotonicity analysis.
  2947   - Added support for quotient types.
  2948   - Added support for "specification" and "ax_specification"
  2949     constructs.
  2950   - Added support for local definitions (for "function" and
  2951     "termination" proofs).
  2952   - Added support for term postprocessors.
  2953   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2954   - Improved efficiency of "destroy_constrs" optimization.
  2955   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2956     record getters.
  2957   - Fixed soundness bug related to higher-order constructors.
  2958   - Fixed soundness bug when "full_descrs" is enabled.
  2959   - Improved precision of set constructs.
  2960   - Added "atoms" option.
  2961   - Added cache to speed up repeated Kodkod invocations on the same
  2962     problems.
  2963   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2964     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2965     "SAT4J_Light".  INCOMPATIBILITY.
  2966   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2967     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2968   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2969 
  2970 * Method "induct" now takes instantiations of the form t, where t is not
  2971   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2972   If this is not intended, t has to be enclosed in parentheses.
  2973   By default, the equalities generated by definitional instantiations
  2974   are pre-simplified, which may cause parameters of inductive cases
  2975   to disappear, or may even delete some of the inductive cases.
  2976   Use "induct (no_simp)" instead of "induct" to restore the old
  2977   behaviour. The (no_simp) option is also understood by the "cases"
  2978   and "nominal_induct" methods, which now perform pre-simplification, too.
  2979   INCOMPATIBILITY.
  2980 
  2981 
  2982 *** HOLCF ***
  2983 
  2984 * Variable names in lemmas generated by the domain package have
  2985 changed; the naming scheme is now consistent with the HOL datatype
  2986 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2987 
  2988 * The domain package no longer defines the function "foo_copy" for
  2989 recursive domain "foo".  The reach lemma is now stated directly in
  2990 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2991 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2992 
  2993 * Most definedness lemmas generated by the domain package (previously
  2994 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2995 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2996 Proofs that used definedness lemmas as intro rules may break,
  2997 potential INCOMPATIBILITY.
  2998 
  2999 * Induction and casedist rules generated by the domain package now
  3000 declare proper case_names (one called "bottom", and one named for each
  3001 constructor).  INCOMPATIBILITY.
  3002 
  3003 * For mutually-recursive domains, separate "reach" and "take_lemma"
  3004 rules are generated for each domain, INCOMPATIBILITY.
  3005 
  3006   foo_bar.reach       ~> foo.reach  bar.reach
  3007   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  3008 
  3009 * Some lemmas generated by the domain package have been renamed for
  3010 consistency with the datatype package, INCOMPATIBILITY.
  3011 
  3012   foo.ind        ~> foo.induct
  3013   foo.finite_ind ~> foo.finite_induct
  3014   foo.coind      ~> foo.coinduct
  3015   foo.casedist   ~> foo.exhaust
  3016   foo.exhaust    ~> foo.nchotomy
  3017 
  3018 * For consistency with other definition packages, the fixrec package
  3019 now generates qualified theorem names, INCOMPATIBILITY.
  3020 
  3021   foo_simps  ~> foo.simps
  3022   foo_unfold ~> foo.unfold
  3023   foo_induct ~> foo.induct
  3024 
  3025 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  3026 method and internal fixrec proofs now use the default simpset instead.
  3027 INCOMPATIBILITY.
  3028 
  3029 * The "contlub" predicate has been removed.  Proof scripts should use
  3030 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  3031 
  3032 * The "admw" predicate has been removed, INCOMPATIBILITY.
  3033 
  3034 * The constants cpair, cfst, and csnd have been removed in favor of
  3035 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  3036 
  3037 
  3038 *** ML ***
  3039 
  3040 * Antiquotations for basic formal entities:
  3041 
  3042     @{class NAME}         -- type class
  3043     @{class_syntax NAME}  -- syntax representation of the above
  3044 
  3045     @{type_name NAME}     -- logical type
  3046     @{type_abbrev NAME}   -- type abbreviation
  3047     @{nonterminal NAME}   -- type of concrete syntactic category
  3048     @{type_syntax NAME}   -- syntax representation of any of the above
  3049 
  3050     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  3051     @{const_abbrev NAME}  -- abbreviated constant
  3052     @{const_syntax NAME}  -- syntax representation of any of the above
  3053 
  3054 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  3055 syntax constant (cf. 'syntax' command).
  3056 
  3057 * Antiquotation @{make_string} inlines a function to print arbitrary
  3058 values similar to the ML toplevel.  The result is compiler dependent
  3059 and may fall back on "?" in certain situations.
  3060 
  3061 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  3062 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  3063 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  3064 not work with the asynchronous Isar document model.
  3065 
  3066 * Configuration options now admit dynamic default values, depending on
  3067 the context or even global references.
  3068 
  3069 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  3070 uses an efficient external library if available (for Poly/ML).
  3071 
  3072 * Renamed some important ML structures, while keeping the old names
  3073 for some time as aliases within the structure Legacy:
  3074 
  3075   OuterKeyword  ~>  Keyword
  3076   OuterLex      ~>  Token
  3077   OuterParse    ~>  Parse
  3078   OuterSyntax   ~>  Outer_Syntax
  3079   PrintMode     ~>  Print_Mode
  3080   SpecParse     ~>  Parse_Spec
  3081   ThyInfo       ~>  Thy_Info
  3082   ThyLoad       ~>  Thy_Load
  3083   ThyOutput     ~>  Thy_Output
  3084   TypeInfer     ~>  Type_Infer
  3085 
  3086 Note that "open Legacy" simplifies porting of sources, but forgetting
  3087 to remove it again will complicate porting again in the future.
  3088 
  3089 * Most operations that refer to a global context are named
  3090 accordingly, e.g. Simplifier.global_context or
  3091 ProofContext.init_global.  There are some situations where a global
  3092 context actually works, but under normal circumstances one needs to
  3093 pass the proper local context through the code!
  3094 
  3095 * Discontinued old TheoryDataFun with its copy/init operation -- data
  3096 needs to be pure.  Functor Theory_Data_PP retains the traditional
  3097 Pretty.pp argument to merge, which is absent in the standard
  3098 Theory_Data version.
  3099 
  3100 * Sorts.certify_sort and derived "cert" operations for types and terms
  3101 no longer minimize sorts.  Thus certification at the boundary of the
  3102 inference kernel becomes invariant under addition of class relations,
  3103 which is an important monotonicity principle.  Sorts are now minimized
  3104 in the syntax layer only, at the boundary between the end-user and the
  3105 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  3106 explicitly in rare situations.
  3107 
  3108 * Renamed old-style Drule.standard to Drule.export_without_context, to
  3109 emphasize that this is in no way a standard operation.
  3110 INCOMPATIBILITY.
  3111 
  3112 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  3113 usual for resolution.  Rare INCOMPATIBILITY.
  3114 
  3115 * Renamed varify/unvarify operations to varify_global/unvarify_global
  3116 to emphasize that these only work in a global situation (which is
  3117 quite rare).
  3118 
  3119 * Curried take and drop in library.ML; negative length is interpreted
  3120 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  3121 
  3122 * Proof terms: type substitutions on proof constants now use canonical
  3123 order of type variables.  INCOMPATIBILITY for tools working with proof
  3124 terms.
  3125 
  3126 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  3127 may no longer carry premises.  User-level specifications are
  3128 transformed accordingly by Thm.add_axiom/add_def.
  3129 
  3130 
  3131 *** System ***
  3132 
  3133 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  3134 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  3135 proof terms are enabled unconditionally in the new HOL-Proofs image.
  3136 
  3137 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  3138 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  3139 respectively.
  3140 
  3141 * Old lib/scripts/polyml-platform is superseded by the
  3142 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  3143 variant, even on a 64 bit machine.  The following example setting
  3144 prefers 64 bit if available:
  3145 
  3146   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  3147 
  3148 * The preliminary Isabelle/jEdit application demonstrates the emerging
  3149 Isabelle/Scala layer for advanced prover interaction and integration.
  3150 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  3151 component.
  3152 
  3153 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  3154 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  3155 similar to the default assignment of the document preparation system
  3156 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  3157 provides some operations for direct access to the font without asking
  3158 the user for manual installation.
  3159 
  3160 
  3161 
  3162 New in Isabelle2009-1 (December 2009)
  3163 -------------------------------------
  3164 
  3165 *** General ***
  3166 
  3167 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  3168 one backslash should be used, even in ML sources.
  3169 
  3170 
  3171 *** Pure ***
  3172 
  3173 * Locale interpretation propagates mixins along the locale hierarchy.
  3174 The currently only available mixins are the equations used to map
  3175 local definitions to terms of the target domain of an interpretation.
  3176 
  3177 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  3178 loc" to print all interpretations of locale "loc" in the theory.
  3179 Interpretations in proofs are not shown.
  3180 
  3181 * Thoroughly revised locales tutorial.  New section on conditional
  3182 interpretation.
  3183 
  3184 * On instantiation of classes, remaining undefined class parameters
  3185 are formally declared.  INCOMPATIBILITY.
  3186 
  3187 
  3188 *** Document preparation ***
  3189 
  3190 * New generalized style concept for printing terms: @{foo (style) ...}
  3191 instead of @{foo_style style ...}  (old form is still retained for
  3192 backward compatibility).  Styles can be also applied for
  3193 antiquotations prop, term_type and typeof.
  3194 
  3195 
  3196 *** HOL ***
  3197 
  3198 * New proof method "smt" for a combination of first-order logic with
  3199 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  3200 fixed-size bitvectors; there is also basic support for higher-order
  3201 features (esp. lambda abstractions).  It is an incomplete decision
  3202 procedure based on external SMT solvers using the oracle mechanism;
  3203 for the SMT solver Z3, this method is proof-producing.  Certificates
  3204 are provided to avoid calling the external solvers solely for
  3205 re-checking proofs.  Due to a remote SMT service there is no need for
  3206 installing SMT solvers locally.  See src/HOL/SMT.
  3207 
  3208 * New commands to load and prove verification conditions generated by
  3209 the Boogie program verifier or derived systems (e.g. the Verifying C
  3210 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  3211 
  3212 * New counterexample generator tool 'nitpick' based on the Kodkod
  3213 relational model finder.  See src/HOL/Tools/Nitpick and
  3214 src/HOL/Nitpick_Examples.
  3215 
  3216 * New commands 'code_pred' and 'values' to invoke the predicate
  3217 compiler and to enumerate values of inductive predicates.
  3218 
  3219 * A tabled implementation of the reflexive transitive closure.
  3220 
  3221 * New implementation of quickcheck uses generic code generator;
  3222 default generators are provided for all suitable HOL types, records
  3223 and datatypes.  Old quickcheck can be re-activated importing theory
  3224 Library/SML_Quickcheck.
  3225 
  3226 * New testing tool Mirabelle for automated proof tools.  Applies
  3227 several tools and tactics like sledgehammer, metis, or quickcheck, to
  3228 every proof step in a theory.  To be used in batch mode via the
  3229 "mirabelle" utility.
  3230 
  3231 * New proof method "sos" (sum of squares) for nonlinear real
  3232 arithmetic (originally due to John Harison). It requires theory
  3233 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  3234 works well in practice on quantifier-free real arithmetic with +, -,
  3235 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  3236 inequalities between polynomials.  It makes use of external
  3237 semidefinite programming solvers.  Method "sos" generates a
  3238 certificate that can be pasted into the proof thus avoiding the need
  3239 to call an external tool every time the proof is checked.  See
  3240 src/HOL/Library/Sum_Of_Squares.
  3241 
  3242 * New method "linarith" invokes existing linear arithmetic decision
  3243 procedure only.
  3244 
  3245 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  3246 
  3247 * New Sledgehammer option "Full Types" in Proof General settings menu.
  3248 Causes full type information to be output to the ATPs.  This slows
  3249 ATPs down considerably but eliminates a source of unsound "proofs"
  3250 that fail later.
  3251 
  3252 * New method "metisFT": A version of metis that uses full type
  3253 information in order to avoid failures of proof reconstruction.
  3254 
  3255 * New evaluator "approximate" approximates an real valued term using
  3256 the same method as the approximation method.
  3257 
  3258 * Method "approximate" now supports arithmetic expressions as
  3259 boundaries of intervals and implements interval splitting and Taylor
  3260 series expansion.
  3261 
  3262 * ML antiquotation @{code_datatype} inserts definition of a datatype
  3263 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  3264 
  3265 * New theory SupInf of the supremum and infimum operators for sets of
  3266 reals.
  3267 
  3268 * New theory Probability, which contains a development of measure
  3269 theory, eventually leading to Lebesgue integration and probability.
  3270 
  3271 * Extended Multivariate Analysis to include derivation and Brouwer's
  3272 fixpoint theorem.
  3273 
  3274 * Reorganization of number theory, INCOMPATIBILITY:
  3275   - new number theory development for nat and int, in theories Divides
  3276     and GCD as well as in new session Number_Theory
  3277   - some constants and facts now suffixed with _nat and _int
  3278     accordingly
  3279   - former session NumberTheory now named Old_Number_Theory, including
  3280     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  3281   - moved theory Pocklington from src/HOL/Library to
  3282     src/HOL/Old_Number_Theory
  3283 
  3284 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  3285 lcm of finite and infinite sets. It is shown that they form a complete
  3286 lattice.
  3287 
  3288 * Class semiring_div requires superclass no_zero_divisors and proof of
  3289 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  3290 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  3291 generalized to class semiring_div, subsuming former theorems
  3292 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  3293 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  3294 INCOMPATIBILITY.
  3295 
  3296 * Refinements to lattice classes and sets:
  3297   - less default intro/elim rules in locale variant, more default
  3298     intro/elim rules in class variant: more uniformity
  3299   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  3300     le_inf_iff
  3301   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  3302     sup_aci)
  3303   - renamed ACI to inf_sup_aci
  3304   - new class "boolean_algebra"
  3305   - class "complete_lattice" moved to separate theory
  3306     "Complete_Lattice"; corresponding constants (and abbreviations)
  3307     renamed and with authentic syntax:
  3308     Set.Inf ~>    Complete_Lattice.Inf
  3309     Set.Sup ~>    Complete_Lattice.Sup
  3310     Set.INFI ~>   Complete_Lattice.INFI
  3311     Set.SUPR ~>   Complete_Lattice.SUPR
  3312     Set.Inter ~>  Complete_Lattice.Inter
  3313     Set.Union ~>  Complete_Lattice.Union
  3314     Set.INTER ~>  Complete_Lattice.INTER
  3315     Set.UNION ~>  Complete_Lattice.UNION
  3316   - authentic syntax for
  3317     Set.Pow
  3318     Set.image
  3319   - mere abbreviations:
  3320     Set.empty               (for bot)
  3321     Set.UNIV                (for top)
  3322     Set.inter               (for inf, formerly Set.Int)
  3323     Set.union               (for sup, formerly Set.Un)
  3324     Complete_Lattice.Inter  (for Inf)
  3325     Complete_Lattice.Union  (for Sup)
  3326     Complete_Lattice.INTER  (for INFI)
  3327     Complete_Lattice.UNION  (for SUPR)
  3328   - object-logic definitions as far as appropriate
  3329 
  3330 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  3331 Un_subset_iff are explicitly deleted as default simp rules; then also
  3332 their lattice counterparts le_inf_iff and le_sup_iff have to be
  3333 deleted to achieve the desired effect.
  3334 
  3335 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  3336 rules by default any longer; the same applies to min_max.inf_absorb1
  3337 etc.  INCOMPATIBILITY.
  3338 
  3339 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  3340 pred_set_conv by default.  INCOMPATIBILITY.
  3341 
  3342 * Power operations on relations and functions are now one dedicated
  3343 constant "compow" with infix syntax "^^".  Power operation on
  3344 multiplicative monoids retains syntax "^" and is now defined generic
  3345 in class power.  INCOMPATIBILITY.
  3346 
  3347 * Relation composition "R O S" now has a more standard argument order:
  3348 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  3349 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  3350 break, since the O_assoc rule was not rewritten like this.  Fix using
  3351 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  3352 
  3353 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  3354 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  3355 INCOMPATIBILITY.
  3356 
  3357 * Most rules produced by inductive and datatype package have mandatory
  3358 prefixes.  INCOMPATIBILITY.
  3359 
  3360 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  3361 the attribute of the same name.  Each of the theorems in the list
  3362 DERIV_intros assumes composition with an additional function and
  3363 matches a variable to the derivative, which has to be solved by the
  3364 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  3365 of most elementary terms.  Former Maclauren.DERIV_tac and
  3366 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  3367 INCOMPATIBILITY.
  3368 
  3369 * Code generator attributes follow the usual underscore convention:
  3370     code_unfold     replaces    code unfold
  3371     code_post       replaces    code post
  3372     etc.
  3373   INCOMPATIBILITY.
  3374 
  3375 * Renamed methods:
  3376     sizechange -> size_change
  3377     induct_scheme -> induction_schema
  3378   INCOMPATIBILITY.
  3379 
  3380 * Discontinued abbreviation "arbitrary" of constant "undefined".
  3381 INCOMPATIBILITY, use "undefined" directly.
  3382 
  3383 * Renamed theorems:
  3384     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  3385     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  3386     Suc_plus1 -> Suc_eq_plus1
  3387     *anti_sym -> *antisym*
  3388     vector_less_eq_def -> vector_le_def
  3389   INCOMPATIBILITY.
  3390 
  3391 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  3392 INCOMPATIBILITY.
  3393 
  3394 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  3395 INCOMPATIBILITY.
  3396 
  3397 
  3398 *** HOLCF ***
  3399 
  3400 * Theory Representable defines a class "rep" of domains that are
  3401 representable (via an ep-pair) in the universal domain type "udom".
  3402 Instances are provided for all type constructors defined in HOLCF.
  3403 
  3404 * The 'new_domain' command is a purely definitional version of the
  3405 domain package, for representable domains.  Syntax is identical to the
  3406 old domain package.  The 'new_domain' package also supports indirect
  3407 recursion using previously-defined type constructors.  See
  3408 src/HOLCF/ex/New_Domain.thy for examples.
  3409 
  3410 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  3411 on the left-hand side of an equation, and then performs
  3412 simplification.  Rewriting is done using rules declared with the
  3413 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  3414 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  3415 
  3416 * The pattern-match compiler in 'fixrec' can now handle constructors
  3417 with HOL function types.  Pattern-match combinators for the Pair
  3418 constructor are pre-configured.
  3419 
  3420 * The 'fixrec' package now produces better fixed-point induction rules
  3421 for mutually-recursive definitions:  Induction rules have conclusions
  3422 of the form "P foo bar" instead of "P <foo, bar>".
  3423 
  3424 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  3425 been renamed to "below".  The name "below" now replaces "less" in many
  3426 theorem names.  (Legacy theorem names using "less" are still supported
  3427 as well.)
  3428 
  3429 * The 'fixrec' package now supports "bottom patterns".  Bottom
  3430 patterns can be used to generate strictness rules, or to make
  3431 functions more strict (much like the bang-patterns supported by the
  3432 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  3433 examples.
  3434 
  3435 
  3436 *** ML ***
  3437 
  3438 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  3439 errors and run-time exceptions, including detailed source positions.
  3440 
  3441 * Structure Name_Space (formerly NameSpace) now manages uniquely
  3442 identified entries, with some additional information such as source
  3443 position, logical grouping etc.
  3444 
  3445 * Theory and context data is now introduced by the simplified and
  3446 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  3447 to be pure, but the old TheoryDataFun for mutable data (with explicit
  3448 copy operation) is still available for some time.
  3449 
  3450 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  3451 provides a high-level programming interface to synchronized state
  3452 variables with atomic update.  This works via pure function
  3453 application within a critical section -- its runtime should be as
  3454 short as possible; beware of deadlocks if critical code is nested,
  3455 either directly or indirectly via other synchronized variables!
  3456 
  3457 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  3458 wraps raw ML references, explicitly indicating their non-thread-safe
  3459 behaviour.  The Isar toplevel keeps this structure open, to
  3460 accommodate Proof General as well as quick and dirty interactive
  3461 experiments with references.
  3462 
  3463 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  3464 parallel tactical reasoning.
  3465 
  3466 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  3467 are similar to SUBPROOF, but are slightly more flexible: only the
  3468 specified parts of the subgoal are imported into the context, and the
  3469 body tactic may introduce new subgoals and schematic variables.
  3470 
  3471 * Old tactical METAHYPS, which does not observe the proof context, has
  3472 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  3473 or Subgoal.FOCUS etc.
  3474 
  3475 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  3476 functors have their own ML name space there is no point to mark them
  3477 separately.)  Minor INCOMPATIBILITY.
  3478 
  3479 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  3480 
  3481 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  3482 INCOMPATIBILITY.
  3483 
  3484 * Operations of structure Skip_Proof no longer require quick_and_dirty
  3485 mode, which avoids critical setmp.
  3486 
  3487 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  3488 combinators for "args".  INCOMPATIBILITY, need to use simplified
  3489 Attrib/Method.setup introduced in Isabelle2009.
  3490 
  3491 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  3492 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  3493 last resort.  INCOMPATIBILITY.
  3494 
  3495 * Display.pretty_thm now requires a proper context (cf. former
  3496 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  3497 or even Display.pretty_thm_without_context as last resort.
  3498 INCOMPATIBILITY.
  3499 
  3500 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  3501 Syntax.pretty_typ/term directly, preferably with proper context
  3502 instead of global theory.
  3503 
  3504 
  3505 *** System ***
  3506 
  3507 * Further fine tuning of parallel proof checking, scales up to 8 cores
  3508 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  3509 usedir option -q.
  3510 
  3511 * Support for additional "Isabelle components" via etc/components, see
  3512 also the system manual.
  3513 
  3514 * The isabelle makeall tool now operates on all components with
  3515 IsaMakefile, not just hardwired "logics".
  3516 
  3517 * Removed "compress" option from isabelle-process and isabelle usedir;
  3518 this is always enabled.
  3519 
  3520 * Discontinued support for Poly/ML 4.x versions.
  3521 
  3522 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  3523 on a given logic image.  This requires the lighttpd webserver and is
  3524 currently supported on Linux only.
  3525 
  3526 
  3527 
  3528 New in Isabelle2009 (April 2009)
  3529 --------------------------------
  3530 
  3531 *** General ***
  3532 
  3533 * Simplified main Isabelle executables, with less surprises on
  3534 case-insensitive file-systems (such as Mac OS).
  3535 
  3536   - The main Isabelle tool wrapper is now called "isabelle" instead of
  3537     "isatool."
  3538 
  3539   - The former "isabelle" alias for "isabelle-process" has been
  3540     removed (should rarely occur to regular users).
  3541 
  3542   - The former "isabelle-interface" and its alias "Isabelle" have been
  3543     removed (interfaces are now regular Isabelle tools).
  3544 
  3545 Within scripts and make files, the Isabelle environment variables
  3546 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  3547 respectively.  (The latter are still available as legacy feature.)
  3548 
  3549 The old isabelle-interface wrapper could react in confusing ways if
  3550 the interface was uninstalled or changed otherwise.  Individual
  3551 interface tool configuration is now more explicit, see also the
  3552 Isabelle system manual.  In particular, Proof General is now available
  3553 via "isabelle emacs".
  3554 
  3555 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  3556 purge installed copies of Isabelle executables and re-run "isabelle
  3557 install -p ...", or use symlinks.
  3558 
  3559 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  3560 old ~/isabelle, which was slightly non-standard and apt to cause
  3561 surprises on case-insensitive file-systems (such as Mac OS).
  3562 
  3563 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  3564 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  3565 care is required when using older releases of Isabelle.  Note that
  3566 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  3567 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  3568 
  3569 * Proofs of fully specified statements are run in parallel on
  3570 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  3571 a regular 4-core machine, if the initial heap space is made reasonably
  3572 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  3573 
  3574 * The main reference manuals ("isar-ref", "implementation", and
  3575 "system") have been updated and extended.  Formally checked references
  3576 as hyperlinks are now available uniformly.
  3577 
  3578 
  3579 *** Pure ***
  3580 
  3581 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  3582 respects.  The most important changes are listed below.  See the
  3583 Tutorial on Locales ("locales" manual) for details.
  3584 
  3585 - In locale expressions, instantiation replaces renaming.  Parameters
  3586 must be declared in a for clause.  To aid compatibility with previous
  3587 parameter inheritance, in locale declarations, parameters that are not
  3588 'touched' (instantiation position "_" or omitted) are implicitly added
  3589 with their syntax at the beginning of the for clause.
  3590 
  3591 - Syntax from abbreviations and definitions in locales is available in
  3592 locale expressions and context elements.  The latter is particularly
  3593 useful in locale declarations.
  3594 
  3595 - More flexible mechanisms to qualify names generated by locale
  3596 expressions.  Qualifiers (prefixes) may be specified in locale
  3597 expressions, and can be marked as mandatory (syntax: "name!:") or
  3598 optional (syntax "name?:").  The default depends for plain "name:"
  3599 depends on the situation where a locale expression is used: in
  3600 commands 'locale' and 'sublocale' prefixes are optional, in
  3601 'interpretation' and 'interpret' prefixes are mandatory.  The old
  3602 implicit qualifiers derived from the parameter names of a locale are
  3603 no longer generated.
  3604 
  3605 - Command "sublocale l < e" replaces "interpretation l < e".  The
  3606 instantiation clause in "interpretation" and "interpret" (square
  3607 brackets) is no longer available.  Use locale expressions.
  3608 
  3609 - When converting proof scripts, mandatory qualifiers in
  3610 'interpretation' and 'interpret' should be retained by default, even
  3611 if this is an INCOMPATIBILITY compared to former behavior.  In the
  3612 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  3613 in locale expressions range over a single locale instance only.
  3614 
  3615 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  3616 In existing theorem specifications replace the includes element by the
  3617 respective context elements of the included locale, omitting those
  3618 that are already present in the theorem specification.  Multiple
  3619 assume elements of a locale should be replaced by a single one
  3620 involving the locale predicate.  In the proof body, declarations (most
  3621 notably theorems) may be regained by interpreting the respective
  3622 locales in the proof context as required (command "interpret").
  3623 
  3624 If using "includes" in replacement of a target solely because the
  3625 parameter types in the theorem are not as general as in the target,
  3626 consider declaring a new locale with additional type constraints on
  3627 the parameters (context element "constrains").
  3628 
  3629 - Discontinued "locale (open)".  INCOMPATIBILITY.
  3630 
  3631 - Locale interpretation commands no longer attempt to simplify goal.
  3632 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  3633 methods intro_locales and unfold_locales to clarify.
  3634 
  3635 - Locale interpretation commands no longer accept interpretation
  3636 attributes.  INCOMPATIBILITY.
  3637 
  3638 * Class declaration: so-called "base sort" must not be given in import
  3639 list any longer, but is inferred from the specification.  Particularly
  3640 in HOL, write
  3641 
  3642     class foo = ...
  3643 
  3644 instead of
  3645 
  3646     class foo = type + ...
  3647 
  3648 * Class target: global versions of theorems stemming do not carry a
  3649 parameter prefix any longer.  INCOMPATIBILITY.
  3650 
  3651 * Class 'instance' command no longer accepts attached definitions.
  3652 INCOMPATIBILITY, use proper 'instantiation' target instead.
  3653 
  3654 * Recovered hiding of consts, which was accidentally broken in
  3655 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  3656 makes c inaccessible; consider using ``hide (open) const c'' instead.
  3657 
  3658 * Slightly more coherent Pure syntax, with updated documentation in
  3659 isar-ref manual.  Removed locales meta_term_syntax and
  3660 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  3661 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  3662 directly in regular applications.
  3663 
  3664 * There is a new syntactic category "float_const" for signed decimal
  3665 fractions (e.g. 123.45 or -123.45).
  3666 
  3667 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  3668 interface with 'setup' command instead.
  3669 
  3670 * Command 'local_setup' is similar to 'setup', but operates on a local
  3671 theory context.
  3672 
  3673 * The 'axiomatization' command now only works within a global theory
  3674 context.  INCOMPATIBILITY.
  3675 
  3676 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  3677 hypotheses.  Sorts required in the course of reasoning need to be
  3678 covered by the constraints in the initial statement, completed by the
  3679 type instance information of the background theory.  Non-trivial sort
  3680 hypotheses, which rarely occur in practice, may be specified via
  3681 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  3682 
  3683   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  3684 
  3685 The result contains an implicit sort hypotheses as before --
  3686 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  3687 normalization.
  3688 
  3689 * Generalized Isar history, with support for linear undo, direct state
  3690 addressing etc.
  3691 
  3692 * Changed defaults for unify configuration options:
  3693 
  3694   unify_trace_bound = 50 (formerly 25)
  3695   unify_search_bound = 60 (formerly 30)
  3696 
  3697 * Different bookkeeping for code equations (INCOMPATIBILITY):
  3698 
  3699   a) On theory merge, the last set of code equations for a particular
  3700      constant is taken (in accordance with the policy applied by other
  3701      parts of the code generator framework).
  3702 
  3703   b) Code equations stemming from explicit declarations (e.g. code
  3704      attribute) gain priority over default code equations stemming
  3705      from definition, primrec, fun etc.
  3706 
  3707 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  3708 
  3709 * Unified theorem tables for both code generators.  Thus [code
  3710 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  3711 
  3712 * Command 'find_consts' searches for constants based on type and name
  3713 patterns, e.g.
  3714 
  3715     find_consts "_ => bool"
  3716 
  3717 By default, matching is against subtypes, but it may be restricted to
  3718 the whole type.  Searching by name is possible.  Multiple queries are
  3719 conjunctive and queries may be negated by prefixing them with a
  3720 hyphen:
  3721 
  3722     find_consts strict: "_ => bool" name: "Int" -"int => int"
  3723 
  3724 * New 'find_theorems' criterion "solves" matches theorems that
  3725 directly solve the current goal (modulo higher-order unification).
  3726 
  3727 * Auto solve feature for main theorem statements: whenever a new goal
  3728 is stated, "find_theorems solves" is called; any theorems that could
  3729 solve the lemma directly are listed as part of the goal state.
  3730 Cf. associated options in Proof General Isabelle settings menu,
  3731 enabled by default, with reasonable timeout for pathological cases of
  3732 higher-order unification.
  3733 
  3734 
  3735 *** Document preparation ***
  3736 
  3737 * Antiquotation @{lemma} now imitates a regular terminal proof,
  3738 demanding keyword 'by' and supporting the full method expression
  3739 syntax just like the Isar command 'by'.
  3740 
  3741 
  3742 *** HOL ***
  3743 
  3744 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  3745 points Main and Complex_Main remain as before.
  3746 
  3747 * Logic image HOL-Plain provides a minimal HOL with the most important
  3748 tools available (inductive, datatype, primrec, ...).  This facilitates
  3749 experimentation and tool development.  Note that user applications
  3750 (and library theories) should never refer to anything below theory
  3751 Main, as before.
  3752 
  3753 * Logic image HOL-Main stops at theory Main, and thus facilitates
  3754 experimentation due to shorter build times.
  3755 
  3756 * Logic image HOL-NSA contains theories of nonstandard analysis which
  3757 were previously part of former HOL-Complex.  Entry point Hyperreal
  3758 remains valid, but theories formerly using Complex_Main should now use
  3759 new entry point Hypercomplex.
  3760 
  3761 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  3762 Posix processes.  Avoids potentially expensive forking of the ML
  3763 process.  New thread-based implementation also works on non-Unix
  3764 platforms (Cygwin).  Provers are no longer hardwired, but defined
  3765 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  3766 commands are covered in the isar-ref manual.
  3767 
  3768 * Wrapper scripts for remote SystemOnTPTP service allows to use
  3769 sledgehammer without local ATP installation (Vampire etc.). Other
  3770 provers may be included via suitable ML wrappers, see also
  3771 src/HOL/ATP_Linkup.thy.
  3772 
  3773 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  3774 menu.
  3775 
  3776 * The metis method no longer fails because the theorem is too trivial
  3777 (contains the empty clause).
  3778 
  3779 * The metis method now fails in the usual manner, rather than raising
  3780 an exception, if it determines that it cannot prove the theorem.
  3781 
  3782 * Method "coherent" implements a prover for coherent logic (see also
  3783 src/Tools/coherent.ML).
  3784 
  3785 * Constants "undefined" and "default" replace "arbitrary".  Usually
  3786 "undefined" is the right choice to replace "arbitrary", though
  3787 logically there is no difference.  INCOMPATIBILITY.
  3788 
  3789 * Command "value" now integrates different evaluation mechanisms.  The
  3790 result of the first successful evaluation mechanism is printed.  In
  3791 square brackets a particular named evaluation mechanisms may be
  3792 specified (currently, [SML], [code] or [nbe]).  See further
  3793 src/HOL/ex/Eval_Examples.thy.
  3794 
  3795 * Normalization by evaluation now allows non-leftlinear equations.
  3796 Declare with attribute [code nbe].
  3797 
  3798 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  3799 as the structured Isar versions "cases" and "induct", cf. the
  3800 corresponding "cases" and "induct" attributes.  Mutual induction rules
  3801 are now presented as a list of individual projections
  3802 (e.g. foo_bar.inducts for types foo and bar); the old format with
  3803 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  3804 rare situations a different rule is selected --- notably nested tuple
  3805 elimination instead of former prod.exhaust: use explicit (case_tac t
  3806 rule: prod.exhaust) here.
  3807 
  3808 * Attributes "cases", "induct", "coinduct" support "del" option.
  3809 
  3810 * Removed fact "case_split_thm", which duplicates "case_split".
  3811 
  3812 * The option datatype has been moved to a new theory Option.  Renamed
  3813 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  3814 
  3815 * New predicate "strict_mono" classifies strict functions on partial
  3816 orders.  With strict functions on linear orders, reasoning about
  3817 (in)equalities is facilitated by theorems "strict_mono_eq",
  3818 "strict_mono_less_eq" and "strict_mono_less".
  3819 
  3820 * Some set operations are now proper qualified constants with
  3821 authentic syntax.  INCOMPATIBILITY:
  3822 
  3823     op Int ~>   Set.Int
  3824     op Un ~>    Set.Un
  3825     INTER ~>    Set.INTER
  3826     UNION ~>    Set.UNION
  3827     Inter ~>    Set.Inter
  3828     Union ~>    Set.Union
  3829     {} ~>       Set.empty
  3830     UNIV ~>     Set.UNIV
  3831 
  3832 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  3833 theory Set.
  3834 
  3835 * Auxiliary class "itself" has disappeared -- classes without any
  3836 parameter are treated as expected by the 'class' command.
  3837 
  3838 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  3839 
  3840 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  3841 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  3842 
  3843 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  3844 method "approximation".  It proves formulas on real values by using
  3845 interval arithmetic.  In the formulas are also the transcendental
  3846 functions sin, cos, tan, atan, ln, exp and the constant pi are
  3847 allowed. For examples see
  3848 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  3849 
  3850 * Theory "Reflection" now resides in HOL/Library.
  3851 
  3852 * Entry point to Word library now simply named "Word".
  3853 INCOMPATIBILITY.
  3854 
  3855 * Made source layout more coherent with logical distribution
  3856 structure:
  3857 
  3858     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  3859     src/HOL/Library/Code_Message.thy ~> src/HOL/
  3860     src/HOL/Library/GCD.thy ~> src/HOL/
  3861     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  3862     src/HOL/Library/Parity.thy ~> src/HOL/
  3863     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  3864     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  3865     src/HOL/Real/Lubs.thy ~> src/HOL/
  3866     src/HOL/Real/PReal.thy ~> src/HOL/
  3867     src/HOL/Real/Rational.thy ~> src/HOL/
  3868     src/HOL/Real/RComplete.thy ~> src/HOL/
  3869     src/HOL/Real/RealDef.thy ~> src/HOL/
  3870     src/HOL/Real/RealPow.thy ~> src/HOL/
  3871     src/HOL/Real/Real.thy ~> src/HOL/
  3872     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  3873     src/HOL/Complex/Complex.thy ~> src/HOL/
  3874     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  3875     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  3876     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  3877     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  3878     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  3879     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  3880     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  3881     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  3882     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  3883     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  3884     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  3885     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  3886     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  3887     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  3888     src/HOL/Real/Float ~> src/HOL/Library/
  3889     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  3890     src/HOL/Real/RealVector.thy ~> src/HOL/
  3891 
  3892     src/HOL/arith_data.ML ~> src/HOL/Tools
  3893     src/HOL/hologic.ML ~> src/HOL/Tools
  3894     src/HOL/simpdata.ML ~> src/HOL/Tools
  3895     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3896     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3897     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3898     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3899     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3900     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3901     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3902 
  3903     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3904     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3905     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3906     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3907     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3908     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3909 
  3910 * If methods "eval" and "evaluation" encounter a structured proof
  3911 state with !!/==>, only the conclusion is evaluated to True (if
  3912 possible), avoiding strange error messages.
  3913 
  3914 * Method "sizechange" automates termination proofs using (a
  3915 modification of) the size-change principle.  Requires SAT solver.  See
  3916 src/HOL/ex/Termination.thy for examples.
  3917 
  3918 * Simplifier: simproc for let expressions now unfolds if bound
  3919 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3920 
  3921 * Method "arith": Linear arithmetic now ignores all inequalities when
  3922 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3923 
  3924 * New attribute "arith" for facts that should always be used
  3925 automatically by arithmetic. It is intended to be used locally in
  3926 proofs, e.g.
  3927 
  3928   assumes [arith]: "x > 0"
  3929 
  3930 Global usage is discouraged because of possible performance impact.
  3931 
  3932 * New classes "top" and "bot" with corresponding operations "top" and
  3933 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3934 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3935 
  3936 * Changed definition lemma "less_fun_def" in order to provide an
  3937 instance for preorders on functions; use lemma "less_le" instead.
  3938 INCOMPATIBILITY.
  3939 
  3940 * Theory Orderings: class "wellorder" moved here, with explicit
  3941 induction rule "less_induct" as assumption.  For instantiation of
  3942 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3943 INCOMPATIBILITY.
  3944 
  3945 * Theory Orderings: added class "preorder" as superclass of "order".
  3946 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3947 etc. slightly changed.  Some theorems named order_class.* now named
  3948 preorder_class.*.
  3949 
  3950 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3951 "diag" to "Id_on".
  3952 
  3953 * Theory Finite_Set: added a new fold combinator of type
  3954 
  3955   ('a => 'b => 'b) => 'b => 'a set => 'b
  3956 
  3957 Occasionally this is more convenient than the old fold combinator
  3958 which is now defined in terms of the new one and renamed to
  3959 fold_image.
  3960 
  3961 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3962 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3963 extended with further lemmas!).  At the moment both still exist but
  3964 the former will disappear at some point.
  3965 
  3966 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3967 class recpower.  Type-specific simp rules for various recpower types
  3968 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3969 
  3970 rat_power_0    -> power_0
  3971 rat_power_Suc  -> power_Suc
  3972 realpow_0      -> power_0
  3973 realpow_Suc    -> power_Suc
  3974 complexpow_0   -> power_0
  3975 complexpow_Suc -> power_Suc
  3976 power_poly_0   -> power_0
  3977 power_poly_Suc -> power_Suc
  3978 
  3979 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3980 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3981 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3982 of lemmas from Divides has been generalized from nat to class
  3983 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3984 renames resulting from duplicate elimination:
  3985 
  3986     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3987     zero_dvd_iff ~>         dvd_0_left_iff
  3988     dvd_0 ~>                dvd_0_right
  3989     DIVISION_BY_ZERO_DIV ~> div_by_0
  3990     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3991     mult_div ~>             div_mult_self2_is_id
  3992     mult_mod ~>             mod_mult_self2_is_0
  3993 
  3994 * Theory IntDiv: removed many lemmas that are instances of class-based
  3995 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3996 rename old lemmas as follows:
  3997 
  3998 dvd_diff               -> nat_dvd_diff
  3999 dvd_zminus_iff         -> dvd_minus_iff
  4000 mod_add1_eq            -> mod_add_eq
  4001 mod_mult1_eq           -> mod_mult_right_eq
  4002 mod_mult1_eq'          -> mod_mult_left_eq
  4003 mod_mult_distrib_mod   -> mod_mult_eq
  4004 nat_mod_add_left_eq    -> mod_add_left_eq
  4005 nat_mod_add_right_eq   -> mod_add_right_eq
  4006 nat_mod_div_trivial    -> mod_div_trivial
  4007 nat_mod_mod_trivial    -> mod_mod_trivial
  4008 zdiv_zadd_self1        -> div_add_self1
  4009 zdiv_zadd_self2        -> div_add_self2
  4010 zdiv_zmult_self1       -> div_mult_self2_is_id
  4011 zdiv_zmult_self2       -> div_mult_self1_is_id
  4012 zdvd_triv_left         -> dvd_triv_left
  4013 zdvd_triv_right        -> dvd_triv_right
  4014 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  4015 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  4016 zmod_zadd_left_eq      -> mod_add_left_eq
  4017 zmod_zadd_right_eq     -> mod_add_right_eq
  4018 zmod_zadd_self1        -> mod_add_self1
  4019 zmod_zadd_self2        -> mod_add_self2
  4020 zmod_zadd1_eq          -> mod_add_eq
  4021 zmod_zdiff1_eq         -> mod_diff_eq
  4022 zmod_zdvd_zmod         -> mod_mod_cancel
  4023 zmod_zmod_cancel       -> mod_mod_cancel
  4024 zmod_zmult_self1       -> mod_mult_self2_is_0
  4025 zmod_zmult_self2       -> mod_mult_self1_is_0
  4026 zmod_1                 -> mod_by_1
  4027 zdiv_1                 -> div_by_1
  4028 zdvd_abs1              -> abs_dvd_iff
  4029 zdvd_abs2              -> dvd_abs_iff
  4030 zdvd_refl              -> dvd_refl
  4031 zdvd_trans             -> dvd_trans
  4032 zdvd_zadd              -> dvd_add
  4033 zdvd_zdiff             -> dvd_diff
  4034 zdvd_zminus_iff        -> dvd_minus_iff
  4035 zdvd_zminus2_iff       -> minus_dvd_iff
  4036 zdvd_zmultD            -> dvd_mult_right
  4037 zdvd_zmultD2           -> dvd_mult_left
  4038 zdvd_zmult_mono        -> mult_dvd_mono
  4039 zdvd_0_right           -> dvd_0_right
  4040 zdvd_0_left            -> dvd_0_left_iff
  4041 zdvd_1_left            -> one_dvd
  4042 zminus_dvd_iff         -> minus_dvd_iff
  4043 
  4044 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  4045 
  4046 * The real numbers offer decimal input syntax: 12.34 is translated
  4047 into 1234/10^2. This translation is not reversed upon output.
  4048 
  4049 * Theory Library/Polynomial defines an abstract type 'a poly of
  4050 univariate polynomials with coefficients of type 'a.  In addition to
  4051 the standard ring operations, it also supports div and mod.  Code
  4052 generation is also supported, using list-style constructors.
  4053 
  4054 * Theory Library/Inner_Product defines a class of real_inner for real
  4055 inner product spaces, with an overloaded operation inner :: 'a => 'a
  4056 => real.  Class real_inner is a subclass of real_normed_vector from
  4057 theory RealVector.
  4058 
  4059 * Theory Library/Product_Vector provides instances for the product
  4060 type 'a * 'b of several classes from RealVector and Inner_Product.
  4061 Definitions of addition, subtraction, scalar multiplication, norms,
  4062 and inner products are included.
  4063 
  4064 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  4065 addition to the field operations, numerals and case syntax are also
  4066 supported.
  4067 
  4068 * Theory Library/Diagonalize provides constructive version of Cantor's
  4069 first diagonalization argument.
  4070 
  4071 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  4072 zlcm (for int); carried together from various gcd/lcm developements in
  4073 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  4074 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  4075 may recover tupled syntax as follows:
  4076 
  4077     hide (open) const gcd
  4078     abbreviation gcd where
  4079       "gcd == (%(a, b). GCD.gcd a b)"
  4080     notation (output)
  4081       GCD.gcd ("gcd '(_, _')")
  4082 
  4083 The same works for lcm, zgcd, zlcm.
  4084 
  4085 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  4086 instantiations for algebraic structures.  Removed some duplicate
  4087 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  4088 
  4089 * ML antiquotation @{code} takes a constant as argument and generates
  4090 corresponding code in background and inserts name of the corresponding
  4091 resulting ML value/function/datatype constructor binding in place.
  4092 All occurrences of @{code} with a single ML block are generated
  4093 simultaneously.  Provides a generic and safe interface for
  4094 instrumentalizing code generation.  See
  4095 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  4096 In future you ought to refrain from ad-hoc compiling generated SML
  4097 code on the ML toplevel.  Note that (for technical reasons) @{code}
  4098 cannot refer to constants for which user-defined serializations are
  4099 set.  Refer to the corresponding ML counterpart directly in that
  4100 cases.
  4101 
  4102 * Command 'rep_datatype': instead of theorem names the command now
  4103 takes a list of terms denoting the constructors of the type to be
  4104 represented as datatype.  The characteristic theorems have to be
  4105 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  4106 have disappeared in favour of existing ones:
  4107 
  4108     unit_induct                 ~> unit.induct
  4109     prod_induct                 ~> prod.induct
  4110     sum_induct                  ~> sum.induct
  4111     Suc_Suc_eq                  ~> nat.inject
  4112     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  4113 
  4114 
  4115 *** HOL-Algebra ***
  4116 
  4117 * New locales for orders and lattices where the equivalence relation
  4118 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  4119 locales use a record structure with field eq for the equivalence.
  4120 
  4121 * New theory of factorial domains.
  4122 
  4123 * Units_l_inv and Units_r_inv are now simp rules by default.
  4124 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  4125 and/or r_inv will now also require deletion of these lemmas.
  4126 
  4127 * Renamed the following theorems, INCOMPATIBILITY:
  4128 
  4129 UpperD ~> Upper_memD
  4130 LowerD ~> Lower_memD
  4131 least_carrier ~> least_closed
  4132 greatest_carrier ~> greatest_closed
  4133 greatest_Lower_above ~> greatest_Lower_below
  4134 one_zero ~> carrier_one_zero
  4135 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  4136 
  4137 
  4138 *** HOL-Nominal ***
  4139 
  4140 * Nominal datatypes can now contain type-variables.
  4141 
  4142 * Commands 'nominal_inductive' and 'equivariance' work with local
  4143 theory targets.
  4144 
  4145 * Nominal primrec can now works with local theory targets and its
  4146 specification syntax now conforms to the general format as seen in
  4147 'inductive' etc.
  4148 
  4149 * Method "perm_simp" honours the standard simplifier attributes
  4150 (no_asm), (no_asm_use) etc.
  4151 
  4152 * The new predicate #* is defined like freshness, except that on the
  4153 left hand side can be a set or list of atoms.
  4154 
  4155 * Experimental command 'nominal_inductive2' derives strong induction
  4156 principles for inductive definitions.  In contrast to
  4157 'nominal_inductive', which can only deal with a fixed number of
  4158 binders, it can deal with arbitrary expressions standing for sets of
  4159 atoms to be avoided.  The only inductive definition we have at the
  4160 moment that needs this generalisation is the typing rule for Lets in
  4161 the algorithm W:
  4162 
  4163  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  4164  -----------------------------------------------------------------
  4165          Gamma |- Let x be t1 in t2 : T2
  4166 
  4167 In this rule one wants to avoid all the binders that are introduced by
  4168 "close Gamma T1".  We are looking for other examples where this
  4169 feature might be useful.  Please let us know.
  4170 
  4171 
  4172 *** HOLCF ***
  4173 
  4174 * Reimplemented the simplification procedure for proving continuity
  4175 subgoals.  The new simproc is extensible; users can declare additional
  4176 continuity introduction rules with the attribute [cont2cont].
  4177 
  4178 * The continuity simproc now uses a different introduction rule for
  4179 solving continuity subgoals on terms with lambda abstractions.  In
  4180 some rare cases the new simproc may fail to solve subgoals that the
  4181 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  4182 Potential INCOMPATIBILITY.
  4183 
  4184 * Command 'fixrec': specification syntax now conforms to the general
  4185 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  4186 examples.  INCOMPATIBILITY.
  4187 
  4188 
  4189 *** ZF ***
  4190 
  4191 * Proof of Zorn's Lemma for partial orders.
  4192 
  4193 
  4194 *** ML ***
  4195 
  4196 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  4197 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  4198 depends on multithreading, so timouts will not work before Poly/ML
  4199 5.2.1!
  4200 
  4201 * High-level support for concurrent ML programming, see
  4202 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  4203 particularly convenient to organize independent functional
  4204 computations.  The concept of "synchronized variables" provides a
  4205 higher-order interface for components with shared state, avoiding the
  4206 delicate details of mutexes and condition variables.  (Requires
  4207 Poly/ML 5.2.1 or later.)
  4208 
  4209 * ML bindings produced via Isar commands are stored within the Isar
  4210 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  4211 become thread-safe and work with undo as expected (concerning
  4212 top-level bindings, not side-effects on global references).
  4213 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  4214 compiler at runtime; really global bindings need to be given outside a
  4215 theory.  (Requires Poly/ML 5.2 or later.)
  4216 
  4217 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  4218 context.  Top-level ML bindings are stored within the proof context in
  4219 a purely sequential fashion, disregarding the nested proof structure.
  4220 ML bindings introduced by 'ML_prf' are discarded at the end of the
  4221 proof.  (Requires Poly/ML 5.2 or later.)
  4222 
  4223 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  4224 and Method.setup, as well as Isar commands 'attribute_setup' and
  4225 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  4226 existing code accordingly, or use plain 'setup' together with old
  4227 Method.add_method.
  4228 
  4229 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  4230 to 'a -> thm, while results are always tagged with an authentic oracle
  4231 name.  The Isar command 'oracle' is now polymorphic, no argument type
  4232 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  4233 accordingly.  Note that extra performance may be gained by producing
  4234 the cterm carefully, avoiding slow Thm.cterm_of.
  4235 
  4236 * Simplified interface for defining document antiquotations via
  4237 ThyOutput.antiquotation, ThyOutput.output, and optionally
  4238 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  4239 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  4240 examples.
  4241 
  4242 * More systematic treatment of long names, abstract name bindings, and
  4243 name space operations.  Basic operations on qualified names have been
  4244 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  4245 Long_Name.append.  Old type bstring has been mostly replaced by
  4246 abstract type binding (see structure Binding), which supports precise
  4247 qualification by packages and local theory targets, as well as proper
  4248 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  4249 bstring values into Binding.name, or better pass through abstract
  4250 bindings everywhere.  See further src/Pure/General/long_name.ML,
  4251 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  4252 
  4253 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  4254 LocalTheory.note etc.) now refer to the *full* internal name, not the
  4255 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  4256 
  4257 * Disposed old type and term read functions (Sign.read_def_typ,
  4258 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  4259 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  4260 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  4261 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  4262 resort for legacy applications.
  4263 
  4264 * Disposed old declarations, tactics, tactic combinators that refer to
  4265 the simpset or claset of an implicit theory (such as Addsimps,
  4266 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  4267 embedded ML text, or local_simpset_of with a proper context passed as
  4268 explicit runtime argument.
  4269 
  4270 * Rules and tactics that read instantiations (read_instantiate,
  4271 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  4272 context, which is required for parsing and type-checking.  Moreover,
  4273 the variables are specified as plain indexnames, not string encodings
  4274 thereof.  INCOMPATIBILITY.
  4275 
  4276 * Generic Toplevel.add_hook interface allows to analyze the result of
  4277 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  4278 for theorem dependency output of transactions resulting in a new
  4279 theory state.
  4280 
  4281 * ML antiquotations: block-structured compilation context indicated by
  4282 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  4283 
  4284   @{binding name}                         - basic name binding
  4285   @{let ?pat = term}                      - term abbreviation (HO matching)
  4286   @{note name = fact}                     - fact abbreviation
  4287   @{thm fact}                             - singleton fact (with attributes)
  4288   @{thms fact}                            - general fact (with attributes)
  4289   @{lemma prop by method}                 - singleton goal
  4290   @{lemma prop by meth1 meth2}            - singleton goal
  4291   @{lemma prop1 ... propN by method}      - general goal
  4292   @{lemma prop1 ... propN by meth1 meth2} - general goal
  4293   @{lemma (open) ...}                     - open derivation
  4294 
  4295 
  4296 *** System ***
  4297 
  4298 * The Isabelle "emacs" tool provides a specific interface to invoke
  4299 Proof General / Emacs, with more explicit failure if that is not
  4300 installed (the old isabelle-interface script silently falls back on
  4301 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  4302 installation location of the Proof General distribution.
  4303 
  4304 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  4305 the Isabelle process into a JVM/Scala application.  See
  4306 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  4307 process wrapper has been discontinued.)
  4308 
  4309 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  4310 
  4311 * Various status messages (with exact source position information) are
  4312 emitted, if proper markup print mode is enabled.  This allows
  4313 user-interface components to provide detailed feedback on internal
  4314 prover operations.
  4315 
  4316 
  4317 
  4318 New in Isabelle2008 (June 2008)
  4319 -------------------------------
  4320 
  4321 *** General ***
  4322 
  4323 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  4324 and updated, with formally checked references as hyperlinks.
  4325 
  4326 * Theory loader: use_thy (and similar operations) no longer set the
  4327 implicit ML context, which was occasionally hard to predict and in
  4328 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  4329 provides a proper context already.
  4330 
  4331 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4332 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  4333 'use' within a theory file will do the job.
  4334 
  4335 * Name space merge now observes canonical order, i.e. the second space
  4336 is inserted into the first one, while existing entries in the first
  4337 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  4338 swap theory imports.
  4339 
  4340 * Syntax: symbol \<chi> is now considered a letter.  Potential
  4341 INCOMPATIBILITY in identifier syntax etc.
  4342 
  4343 * Outer syntax: string tokens no longer admit escaped white space,
  4344 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  4345 white space without escapes.
  4346 
  4347 * Outer syntax: string tokens may contain arbitrary character codes
  4348 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  4349 "foo_bar".
  4350 
  4351 
  4352 *** Pure ***
  4353 
  4354 * Context-dependent token translations.  Default setup reverts locally
  4355 fixed variables, and adds hilite markup for undeclared frees.
  4356 
  4357 * Unused theorems can be found using the new command 'unused_thms'.
  4358 There are three ways of invoking it:
  4359 
  4360 (1) unused_thms
  4361      Only finds unused theorems in the current theory.
  4362 
  4363 (2) unused_thms thy_1 ... thy_n -
  4364      Finds unused theorems in the current theory and all of its ancestors,
  4365      excluding the theories thy_1 ... thy_n and all of their ancestors.
  4366 
  4367 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  4368      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  4369      their ancestors, excluding the theories thy_1 ... thy_n and all of
  4370      their ancestors.
  4371 
  4372 In order to increase the readability of the list produced by
  4373 unused_thms, theorems that have been created by a particular instance
  4374 of a theory command such as 'inductive' or 'function' are considered
  4375 to belong to the same "group", meaning that if at least one theorem in
  4376 this group is used, the other theorems in the same group are no longer
  4377 reported as unused.  Moreover, if all theorems in the group are
  4378 unused, only one theorem in the group is displayed.
  4379 
  4380 Note that proof objects have to be switched on in order for
  4381 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  4382 usually the case when using Proof General with the default settings).
  4383 
  4384 * Authentic naming of facts disallows ad-hoc overwriting of previous
  4385 theorems within the same name space.  INCOMPATIBILITY, need to remove
  4386 duplicate fact bindings, or even accidental fact duplications.  Note
  4387 that tools may maintain dynamically scoped facts systematically, using
  4388 PureThy.add_thms_dynamic.
  4389 
  4390 * Command 'hide' now allows to hide from "fact" name space as well.
  4391 
  4392 * Eliminated destructive theorem database, simpset, claset, and
  4393 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  4394 update of theories within ML code.
  4395 
  4396 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  4397 INCOMPATIBILITY, object-logics depending on former Pure require
  4398 additional setup PureThy.old_appl_syntax_setup; object-logics
  4399 depending on former CPure need to refer to Pure.
  4400 
  4401 * Commands 'use' and 'ML' are now purely functional, operating on
  4402 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  4403 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  4404 INCOMPATIBILITY.
  4405 
  4406 * Command 'setup': discontinued implicit version with ML reference.
  4407 
  4408 * Instantiation target allows for simultaneous specification of class
  4409 instance operations together with an instantiation proof.
  4410 Type-checking phase allows to refer to class operations uniformly.
  4411 See src/HOL/Complex/Complex.thy for an Isar example and
  4412 src/HOL/Library/Eval.thy for an ML example.
  4413 
  4414 * Indexing of literal facts: be more serious about including only
  4415 facts from the visible specification/proof context, but not the
  4416 background context (locale etc.).  Affects `prop` notation and method
  4417 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  4418 situations.
  4419 
  4420 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  4421 "(open)" option, which used to expose internal bound variables to the
  4422 proof text.
  4423 
  4424 * Isar statements: removed obsolete case "rule_context".
  4425 INCOMPATIBILITY, better use explicit fixes/assumes.
  4426 
  4427 * Locale proofs: default proof step now includes 'unfold_locales';
  4428 hence 'proof' without argument may be used to unfold locale
  4429 predicates.
  4430 
  4431 
  4432 *** Document preparation ***
  4433 
  4434 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  4435 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  4436 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  4437 spot); renamed link color from "darkblue" to "linkcolor" (default
  4438 value unchanged, can be redefined via \definecolor); no longer sets
  4439 "a4paper" option (unnecessary or even intrusive).
  4440 
  4441 * Antiquotation @{lemma A method} proves proposition A by the given
  4442 method (either a method name or a method name plus (optional) method
  4443 arguments in parentheses) and prints A just like @{prop A}.
  4444 
  4445 
  4446 *** HOL ***
  4447 
  4448 * New primrec package.  Specification syntax conforms in style to
  4449 definition/function/....  No separate induction rule is provided.  The
  4450 "primrec" command distinguishes old-style and new-style specifications
  4451 by syntax.  The former primrec package is now named OldPrimrecPackage.
  4452 When adjusting theories, beware: constants stemming from new-style
  4453 primrec specifications have authentic syntax.
  4454 
  4455 * Metis prover is now an order of magnitude faster, and also works
  4456 with multithreading.
  4457 
  4458 * Metis: the maximum number of clauses that can be produced from a
  4459 theorem is now given by the attribute max_clauses.  Theorems that
  4460 exceed this number are ignored, with a warning printed.
  4461 
  4462 * Sledgehammer no longer produces structured proofs by default. To
  4463 enable, declare [[sledgehammer_full = true]].  Attributes
  4464 reconstruction_modulus, reconstruction_sorts renamed
  4465 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  4466 
  4467 * Method "induct_scheme" derives user-specified induction rules
  4468 from well-founded induction and completeness of patterns. This factors
  4469 out some operations that are done internally by the function package
  4470 and makes them available separately.  See
  4471 src/HOL/ex/Induction_Scheme.thy for examples.
  4472 
  4473 * More flexible generation of measure functions for termination
  4474 proofs: Measure functions can be declared by proving a rule of the
  4475 form "is_measure f" and giving it the [measure_function] attribute.
  4476 The "is_measure" predicate is logically meaningless (always true), and
  4477 just guides the heuristic.  To find suitable measure functions, the
  4478 termination prover sets up the goal "is_measure ?f" of the appropriate
  4479 type and generates all solutions by prolog-style backwards proof using
  4480 the declared rules.
  4481 
  4482 This setup also deals with rules like 
  4483 
  4484   "is_measure f ==> is_measure (list_size f)"
  4485 
  4486 which accommodates nested datatypes that recurse through lists.
  4487 Similar rules are predeclared for products and option types.
  4488 
  4489 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  4490 
  4491   INCOMPATIBILITIES:
  4492 
  4493   - Definitions of overloaded constants on sets have to be replaced by
  4494     definitions on => and bool.
  4495 
  4496   - Some definitions of overloaded operators on sets can now be proved
  4497     using the definitions of the operators on => and bool.  Therefore,
  4498     the following theorems have been renamed:
  4499 
  4500       subset_def   -> subset_eq
  4501       psubset_def  -> psubset_eq
  4502       set_diff_def -> set_diff_eq
  4503       Compl_def    -> Compl_eq
  4504       Sup_set_def  -> Sup_set_eq
  4505       Inf_set_def  -> Inf_set_eq
  4506       sup_set_def  -> sup_set_eq
  4507       inf_set_def  -> inf_set_eq
  4508 
  4509   - Due to the incompleteness of the HO unification algorithm, some
  4510     rules such as subst may require manual instantiation, if some of
  4511     the unknowns in the rule is a set.
  4512 
  4513   - Higher order unification and forward proofs:
  4514     The proof pattern
  4515 
  4516       have "P (S::'a set)" <...>
  4517       then have "EX S. P S" ..
  4518 
  4519     no longer works (due to the incompleteness of the HO unification
  4520     algorithm) and must be replaced by the pattern
  4521 
  4522       have "EX S. P S"
  4523       proof
  4524         show "P S" <...>
  4525       qed
  4526 
  4527   - Calculational reasoning with subst (or similar rules):
  4528     The proof pattern
  4529 
  4530       have "P (S::'a set)" <...>
  4531       also have "S = T" <...>
  4532       finally have "P T" .
  4533 
  4534     no longer works (for similar reasons as the previous example) and
  4535     must be replaced by something like
  4536 
  4537       have "P (S::'a set)" <...>
  4538       moreover have "S = T" <...>
  4539       ultimately have "P T" by simp
  4540 
  4541   - Tactics or packages written in ML code:
  4542     Code performing pattern matching on types via
  4543 
  4544       Type ("set", [T]) => ...
  4545 
  4546     must be rewritten. Moreover, functions like strip_type or
  4547     binder_types no longer return the right value when applied to a
  4548     type of the form
  4549 
  4550       T1 => ... => Tn => U => bool
  4551 
  4552     rather than
  4553 
  4554       T1 => ... => Tn => U set
  4555 
  4556 * Merged theories Wellfounded_Recursion, Accessible_Part and
  4557 Wellfounded_Relations to theory Wellfounded.
  4558 
  4559 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  4560 
  4561 * Class finite no longer treats UNIV as class parameter.  Use class
  4562 enum from theory Library/Enum instead to achieve a similar effect.
  4563 INCOMPATIBILITY.
  4564 
  4565 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  4566 and "Cons".  INCOMPATIBILITY.
  4567 
  4568 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  4569 Potential INCOMPATIBILITY.
  4570 
  4571 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  4572 injective_fst_snd removed, use split_eta and prod_eqI instead.
  4573 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  4574 
  4575 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  4576 the same name in theory Orderings:
  4577 
  4578   less_trans
  4579   less_linear
  4580   le_imp_less_or_eq
  4581   le_less_trans
  4582   less_le_trans
  4583   less_not_sym
  4584   less_asym
  4585 
  4586 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  4587 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  4588 and different variable names.
  4589 
  4590 * Library/Option_ord.thy: Canonical order on option type.
  4591 
  4592 * Library/RBT.thy: Red-black trees, an efficient implementation of
  4593 finite maps.
  4594 
  4595 * Library/Countable.thy: Type class for countable types.
  4596 
  4597 * Theory Int: The representation of numerals has changed.  The infix
  4598 operator BIT and the bit datatype with constructors B0 and B1 have
  4599 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  4600 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  4601 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  4602 accordingly.
  4603 
  4604 * Theory Nat: definition of <= and < on natural numbers no longer
  4605 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  4606 le_def and less_def have disappeared.  Consider lemmas not_less
  4607 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  4608 
  4609 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  4610 (whose purpose mainly is for various fold_set functionals) have been
  4611 abandoned in favor of the existing algebraic classes
  4612 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  4613 lower_semilattice (resp. upper_semilattice) and linorder.
  4614 INCOMPATIBILITY.
  4615 
  4616 * Theory Transitive_Closure: induct and cases rules now declare proper
  4617 case_names ("base" and "step").  INCOMPATIBILITY.
  4618 
  4619 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  4620 lattices.  The form set-specific version is available as
  4621 Inductive.lfp_ordinal_induct_set.
  4622 
  4623 * Renamed theorems "power.simps" to "power_int.simps".
  4624 INCOMPATIBILITY.
  4625 
  4626 * Class semiring_div provides basic abstract properties of semirings
  4627 with division and modulo operations.  Subsumes former class dvd_mod.
  4628 
  4629 * Merged theories IntDef, Numeral and IntArith into unified theory
  4630 Int.  INCOMPATIBILITY.
  4631 
  4632 * Theory Library/Code_Index: type "index" now represents natural
  4633 numbers rather than integers.  INCOMPATIBILITY.
  4634 
  4635 * New class "uminus" with operation "uminus" (split of from class
  4636 "minus" which now only has operation "minus", binary).
  4637 INCOMPATIBILITY.
  4638 
  4639 * Constants "card", "internal_split", "option_map" now with authentic
  4640 syntax.  INCOMPATIBILITY.
  4641 
  4642 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  4643 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  4644 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  4645 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  4646 Sup_set_def, le_def, less_def, option_map_def now with object
  4647 equality.  INCOMPATIBILITY.
  4648 
  4649 * Records. Removed K_record, and replaced it by pure lambda term
  4650 %x. c. The simplifier setup is now more robust against eta expansion.
  4651 INCOMPATIBILITY: in cases explicitly referring to K_record.
  4652 
  4653 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  4654 
  4655 * Library/ListVector: new theory of arithmetic vector operations.
  4656 
  4657 * Library/Order_Relation: new theory of various orderings as sets of
  4658 pairs.  Defines preorders, partial orders, linear orders and
  4659 well-orders on sets and on types.
  4660 
  4661 
  4662 *** ZF ***
  4663 
  4664 * Renamed some theories to allow to loading both ZF and HOL in the
  4665 same session:
  4666 
  4667   Datatype  -> Datatype_ZF
  4668   Inductive -> Inductive_ZF
  4669   Int       -> Int_ZF
  4670   IntDiv    -> IntDiv_ZF
  4671   Nat       -> Nat_ZF
  4672   List      -> List_ZF
  4673   Main      -> Main_ZF
  4674 
  4675 INCOMPATIBILITY: ZF theories that import individual theories below
  4676 Main might need to be adapted.  Regular theory Main is still
  4677 available, as trivial extension of Main_ZF.
  4678 
  4679 
  4680 *** ML ***
  4681 
  4682 * ML within Isar: antiquotation @{const name} or @{const
  4683 name(typargs)} produces statically-checked Const term.
  4684 
  4685 * Functor NamedThmsFun: data is available to the user as dynamic fact
  4686 (of the same name).  Removed obsolete print command.
  4687 
  4688 * Removed obsolete "use_legacy_bindings" function.
  4689 
  4690 * The ``print mode'' is now a thread-local value derived from a global
  4691 template (the former print_mode reference), thus access becomes
  4692 non-critical.  The global print_mode reference is for session
  4693 management only; user-code should use print_mode_value,
  4694 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  4695 
  4696 * Functions system/system_out provide a robust way to invoke external
  4697 shell commands, with propagation of interrupts (requires Poly/ML
  4698 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  4699 
  4700 
  4701 *** System ***
  4702 
  4703 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  4704 in accordance with Proof General 3.7, which prefers GNU emacs.
  4705 
  4706 * isatool tty runs Isabelle process with plain tty interaction;
  4707 optional line editor may be specified via ISABELLE_LINE_EDITOR
  4708 setting, the default settings attempt to locate "ledit" and "rlwrap".
  4709 
  4710 * isatool browser now works with Cygwin as well, using general
  4711 "javapath" function defined in Isabelle process environment.
  4712 
  4713 * YXML notation provides a simple and efficient alternative to
  4714 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  4715 isatool yxml as described in the Isabelle system manual.
  4716 
  4717 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  4718 provides general wrapper for managing an Isabelle process in a robust
  4719 fashion, with ``cooked'' output from stdin/stderr.
  4720 
  4721 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  4722 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  4723 
  4724 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  4725 way of changing the user's settings is via
  4726 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  4727 script.
  4728 
  4729 * Multithreading.max_threads := 0 refers to the number of actual CPU
  4730 cores of the underlying machine, which is a good starting point for
  4731 optimal performance tuning.  The corresponding usedir option -M allows
  4732 "max" as an alias for "0".  WARNING: does not work on certain versions
  4733 of Mac OS (with Poly/ML 5.1).
  4734 
  4735 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  4736 adverse effect of Isabelle flooding interactive front-ends (notably
  4737 ProofGeneral / XEmacs).
  4738 
  4739 
  4740 
  4741 New in Isabelle2007 (November 2007)
  4742 -----------------------------------
  4743 
  4744 *** General ***
  4745 
  4746 * More uniform information about legacy features, notably a
  4747 warning/error of "Legacy feature: ...", depending on the state of the
  4748 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  4749 legacy features will disappear eventually.
  4750 
  4751 * Theory syntax: the header format ``theory A = B + C:'' has been
  4752 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  4753 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  4754 
  4755 * Theory syntax: the old non-Isar theory file format has been
  4756 discontinued altogether.  Note that ML proof scripts may still be used
  4757 with Isar theories; migration is usually quite simple with the ML
  4758 function use_legacy_bindings.  INCOMPATIBILITY.
  4759 
  4760 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  4761 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  4762 quotes.
  4763 
  4764 * Theory loader: be more serious about observing the static theory
  4765 header specifications (including optional directories), but not the
  4766 accidental file locations of previously successful loads.  The strict
  4767 update policy of former update_thy is now already performed by
  4768 use_thy, so the former has been removed; use_thys updates several
  4769 theories simultaneously, just as 'imports' within a theory header
  4770 specification, but without merging the results.  Potential
  4771 INCOMPATIBILITY: may need to refine theory headers and commands
  4772 ROOT.ML which depend on load order.
  4773 
  4774 * Theory loader: optional support for content-based file
  4775 identification, instead of the traditional scheme of full physical
  4776 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  4777 (cf. the system manual).  The new scheme allows to work with
  4778 non-finished theories in persistent session images, such that source
  4779 files may be moved later on without requiring reloads.
  4780 
  4781 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4782 file (with the same base name as the theory) are considered a legacy
  4783 feature, which will disappear eventually. Even now, the theory loader
  4784 no longer maintains dependencies on such files.
  4785 
  4786 * Syntax: the scope for resolving ambiguities via type-inference is
  4787 now limited to individual terms, instead of whole simultaneous
  4788 specifications as before. This greatly reduces the complexity of the
  4789 syntax module and improves flexibility by separating parsing and
  4790 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  4791 'fixes' etc.) are required in rare situations.
  4792 
  4793 * Syntax: constants introduced by new-style packages ('definition',
  4794 'abbreviation' etc.) are passed through the syntax module in
  4795 ``authentic mode''. This means that associated mixfix annotations
  4796 really stick to such constants, independently of potential name space
  4797 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  4798 trees are represented slightly differently, may need to adapt syntax
  4799 translations accordingly. Use CONST marker in 'translations' and
  4800 @{const_syntax} antiquotation in 'parse_translation' etc.
  4801 
  4802 * Legacy goal package: reduced interface to the bare minimum required
  4803 to keep existing proof scripts running.  Most other user-level
  4804 functions are now part of the OldGoals structure, which is *not* open
  4805 by default (consider isatool expandshort before open OldGoals).
  4806 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  4807 these tend to cause confusion about the actual goal (!) context being
  4808 used here, which is not necessarily the same as the_context().
  4809 
  4810 * Command 'find_theorems': supports "*" wild-card in "name:"
  4811 criterion; "with_dups" option.  Certain ProofGeneral versions might
  4812 support a specific search form (see ProofGeneral/CHANGES).
  4813 
  4814 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  4815 by default, which means that "prems" (and also "fixed variables") are
  4816 suppressed from proof state output.  Note that the ProofGeneral
  4817 settings mechanism allows to change and save options persistently, but
  4818 older versions of Isabelle will fail to start up if a negative prems
  4819 limit is imposed.
  4820 
  4821 * Local theory targets may be specified by non-nested blocks of
  4822 ``context/locale/class ... begin'' followed by ``end''.  The body may
  4823 contain definitions, theorems etc., including any derived mechanism
  4824 that has been implemented on top of these primitives.  This concept
  4825 generalizes the existing ``theorem (in ...)'' towards more versatility
  4826 and scalability.
  4827 
  4828 * Proof General interface: proper undo of final 'end' command;
  4829 discontinued Isabelle/classic mode (ML proof scripts).
  4830 
  4831 
  4832 *** Document preparation ***
  4833 
  4834 * Added antiquotation @{theory name} which prints the given name,
  4835 after checking that it refers to a valid ancestor theory in the
  4836 current context.
  4837 
  4838 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  4839 check the given source text as ML type/structure, printing verbatim.
  4840 
  4841 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  4842 "c args == rhs" given in the current context.  (Any number of
  4843 arguments may be given on the LHS.)
  4844 
  4845 
  4846 *** Pure ***
  4847 
  4848 * The 'class' package offers a combination of axclass and locale to
  4849 achieve Haskell-like type classes in Isabelle.  Definitions and
  4850 theorems within a class context produce both relative results (with
  4851 implicit parameters according to the locale context), and polymorphic
  4852 constants with qualified polymorphism (according to the class
  4853 context).  Within the body context of a 'class' target, a separate
  4854 syntax layer ("user space type system") takes care of converting
  4855 between global polymorphic consts and internal locale representation.
  4856 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  4857 "isatool doc classes" provides a tutorial.
  4858 
  4859 * Generic code generator framework allows to generate executable
  4860 code for ML and Haskell (including Isabelle classes).  A short usage
  4861 sketch:
  4862 
  4863     internal compilation:
  4864         export_code <list of constants (term syntax)> in SML
  4865     writing SML code to a file:
  4866         export_code <list of constants (term syntax)> in SML <filename>
  4867     writing OCaml code to a file:
  4868         export_code <list of constants (term syntax)> in OCaml <filename>
  4869     writing Haskell code to a bunch of files:
  4870         export_code <list of constants (term syntax)> in Haskell <filename>
  4871 
  4872     evaluating closed propositions to True/False using code generation:
  4873         method ``eval''
  4874 
  4875 Reasonable default setup of framework in HOL.
  4876 
  4877 Theorem attributs for selecting and transforming function equations theorems:
  4878 
  4879     [code fun]:        select a theorem as function equation for a specific constant
  4880     [code fun del]:    deselect a theorem as function equation for a specific constant
  4881     [code inline]:     select an equation theorem for unfolding (inlining) in place
  4882     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  4883 
  4884 User-defined serializations (target in {SML, OCaml, Haskell}):
  4885 
  4886     code_const <and-list of constants (term syntax)>
  4887       {(target) <and-list of const target syntax>}+
  4888 
  4889     code_type <and-list of type constructors>
  4890       {(target) <and-list of type target syntax>}+
  4891 
  4892     code_instance <and-list of instances>
  4893       {(target)}+
  4894         where instance ::= <type constructor> :: <class>
  4895 
  4896     code_class <and_list of classes>
  4897       {(target) <and-list of class target syntax>}+
  4898         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4899 
  4900 code_instance and code_class only are effective to target Haskell.
  4901 
  4902 For example usage see src/HOL/ex/Codegenerator.thy and
  4903 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4904 generation from Isabelle/HOL theories is available via "isatool doc
  4905 codegen".
  4906 
  4907 * Code generator: consts in 'consts_code' Isar commands are now
  4908 referred to by usual term syntax (including optional type
  4909 annotations).
  4910 
  4911 * Command 'no_translations' removes translation rules from theory
  4912 syntax.
  4913 
  4914 * Overloaded definitions are now actually checked for acyclic
  4915 dependencies.  The overloading scheme is slightly more general than
  4916 that of Haskell98, although Isabelle does not demand an exact
  4917 correspondence to type class and instance declarations.
  4918 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4919 exotic versions of overloading -- at the discretion of the user!
  4920 
  4921 Polymorphic constants are represented via type arguments, i.e. the
  4922 instantiation that matches an instance against the most general
  4923 declaration given in the signature.  For example, with the declaration
  4924 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4925 as c(nat).  Overloading is essentially simultaneous structural
  4926 recursion over such type arguments.  Incomplete specification patterns
  4927 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4928 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4929 Command 'print_theory' outputs the normalized system of recursive
  4930 equations, see section "definitions".
  4931 
  4932 * Configuration options are maintained within the theory or proof
  4933 context (with name and type bool/int/string), providing a very simple
  4934 interface to a poor-man's version of general context data.  Tools may
  4935 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4936 these values using Config.get etc.  Users may change options via an
  4937 associated attribute of the same name.  This form of context
  4938 declaration works particularly well with commands 'declare' or
  4939 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4940 very easy to avoid global references, which would not observe Isar
  4941 toplevel undo/redo and fail to work with multithreading.
  4942 
  4943 Various global ML references of Pure and HOL have been turned into
  4944 configuration options:
  4945 
  4946   Unify.search_bound		unify_search_bound
  4947   Unify.trace_bound		unify_trace_bound
  4948   Unify.trace_simp		unify_trace_simp
  4949   Unify.trace_types		unify_trace_types
  4950   Simplifier.simp_depth_limit	simp_depth_limit
  4951   Blast.depth_limit		blast_depth_limit
  4952   DatatypeProp.dtK		datatype_distinctness_limit
  4953   fast_arith_neq_limit  	fast_arith_neq_limit
  4954   fast_arith_split_limit	fast_arith_split_limit
  4955 
  4956 * Named collections of theorems may be easily installed as context
  4957 data using the functor NamedThmsFun (see also
  4958 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4959 attributes; there is also a toplevel print command.  This facility is
  4960 just a common case of general context data, which is the preferred way
  4961 for anything more complex than just a list of facts in canonical
  4962 order.
  4963 
  4964 * Isar: command 'declaration' augments a local theory by generic
  4965 declaration functions written in ML.  This enables arbitrary content
  4966 being added to the context, depending on a morphism that tells the
  4967 difference of the original declaration context wrt. the application
  4968 context encountered later on.
  4969 
  4970 * Isar: proper interfaces for simplification procedures.  Command
  4971 'simproc_setup' declares named simprocs (with match patterns, and body
  4972 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4973 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4974 
  4975 * Isar: an extra pair of brackets around attribute declarations
  4976 abbreviates a theorem reference involving an internal dummy fact,
  4977 which will be ignored later --- only the effect of the attribute on
  4978 the background context will persist.  This form of in-place
  4979 declarations is particularly useful with commands like 'declare' and
  4980 'using', for example ``have A using [[simproc a]] by simp''.
  4981 
  4982 * Isar: method "assumption" (and implicit closing of subproofs) now
  4983 takes simple non-atomic goal assumptions into account: after applying
  4984 an assumption as a rule the resulting subgoals are solved by atomic
  4985 assumption steps.  This is particularly useful to finish 'obtain'
  4986 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4987 without referring to the original premise "!!x. P x ==> thesis" in the
  4988 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4989 more permissive.
  4990 
  4991 * Isar: implicit use of prems from the Isar proof context is
  4992 considered a legacy feature.  Common applications like ``have A .''
  4993 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4994 referencing facts explicitly here improves readability and
  4995 maintainability of proof texts.
  4996 
  4997 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4998 the obtained context from the course of reasoning!  For example:
  4999 
  5000   assume "EX x y. A x & B y"   -- "any previous fact"
  5001   then guess x and y by clarify
  5002 
  5003 This technique is potentially adventurous, depending on the facts and
  5004 proof tools being involved here.
  5005 
  5006 * Isar: known facts from the proof context may be specified as literal
  5007 propositions, using ASCII back-quote syntax.  This works wherever
  5008 named facts used to be allowed so far, in proof commands, proof
  5009 methods, attributes etc.  Literal facts are retrieved from the context
  5010 according to unification of type and term parameters.  For example,
  5011 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  5012 theorems in the current context, then these are valid literal facts:
  5013 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  5014 
  5015 There is also a proof method "fact" which does the same composition
  5016 for explicit goal states, e.g. the following proof texts coincide with
  5017 certain special cases of literal facts:
  5018 
  5019   have "A" by fact                 ==  note `A`
  5020   have "A ==> B" by fact           ==  note `A ==> B`
  5021   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  5022   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  5023 
  5024 * Isar: ":" (colon) is no longer a symbolic identifier character in
  5025 outer syntax.  Thus symbolic identifiers may be used without
  5026 additional white space in declarations like this: ``assume *: A''.
  5027 
  5028 * Isar: 'print_facts' prints all local facts of the current context,
  5029 both named and unnamed ones.
  5030 
  5031 * Isar: 'def' now admits simultaneous definitions, e.g.:
  5032 
  5033   def x == "t" and y == "u"
  5034 
  5035 * Isar: added command 'unfolding', which is structurally similar to
  5036 'using', but affects both the goal state and facts by unfolding given
  5037 rewrite rules.  Thus many occurrences of the 'unfold' method or
  5038 'unfolded' attribute may be replaced by first-class proof text.
  5039 
  5040 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  5041 and command 'unfolding' now all support object-level equalities
  5042 (potentially conditional).  The underlying notion of rewrite rule is
  5043 analogous to the 'rule_format' attribute, but *not* that of the
  5044 Simplifier (which is usually more generous).
  5045 
  5046 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  5047 premises of a theorem by n. Useful in conjunction with drule.
  5048 
  5049 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  5050 method expression within a sandbox consisting of the first N
  5051 sub-goals, which need to exist.  For example, ``simp_all [3]''
  5052 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  5053 simplifies all new goals that emerge from applying rule foo to the
  5054 originally first one.
  5055 
  5056 * Isar: schematic goals are no longer restricted to higher-order
  5057 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  5058 expected.
  5059 
  5060 * Isar: the conclusion of a long theorem statement is now either
  5061 'shows' (a simultaneous conjunction, as before), or 'obtains'
  5062 (essentially a disjunction of cases with local parameters and
  5063 assumptions).  The latter allows to express general elimination rules
  5064 adequately; in this notation common elimination rules look like this:
  5065 
  5066   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  5067     assumes "EX x. P x"
  5068     obtains x where "P x"
  5069 
  5070   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  5071     assumes "A & B"
  5072     obtains A and B
  5073 
  5074   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  5075     assumes "A | B"
  5076     obtains
  5077       A
  5078     | B
  5079 
  5080 The subsequent classical rules even refer to the formal "thesis"
  5081 explicitly:
  5082 
  5083   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  5084     obtains "~ thesis"
  5085 
  5086   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  5087     obtains "thesis ==> something"
  5088 
  5089 The actual proof of an 'obtains' statement is analogous to that of the
  5090 Isar proof element 'obtain', only that there may be several cases.
  5091 Optional case names may be specified in parentheses; these will be
  5092 available both in the present proof and as annotations in the
  5093 resulting rule, for later use with the 'cases' method (cf. attribute
  5094 case_names).
  5095 
  5096 * Isar: the assumptions of a long theorem statement are available as
  5097 "assms" fact in the proof context.  This is more appropriate than the
  5098 (historical) "prems", which refers to all assumptions of the current
  5099 context, including those from the target locale, proof body etc.
  5100 
  5101 * Isar: 'print_statement' prints theorems from the current theory or
  5102 proof context in long statement form, according to the syntax of a
  5103 top-level lemma.
  5104 
  5105 * Isar: 'obtain' takes an optional case name for the local context
  5106 introduction rule (default "that").
  5107 
  5108 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  5109 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  5110 to occur.
  5111 
  5112 * Pure: syntax "CONST name" produces a fully internalized constant
  5113 according to the current context.  This is particularly useful for
  5114 syntax translations that should refer to internal constant
  5115 representations independently of name spaces.
  5116 
  5117 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  5118 instead of "FOO ". This allows multiple binder declarations to coexist
  5119 in the same context.  INCOMPATIBILITY.
  5120 
  5121 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  5122 primitive that also works in a locale context (both for constants and
  5123 fixed variables). Type declaration and internal syntactic representation
  5124 of given constants retrieved from the context. Likewise, the
  5125 'no_notation' command allows to remove given syntax annotations from the
  5126 current context.
  5127 
  5128 * Isar/locales: new derived specification elements 'axiomatization',
  5129 'definition', 'abbreviation', which support type-inference, admit
  5130 object-level specifications (equality, equivalence).  See also the
  5131 isar-ref manual.  Examples:
  5132 
  5133   axiomatization
  5134     eq  (infix "===" 50) where
  5135     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  5136 
  5137   definition "f x y = x + y + 1"
  5138   definition g where "g x = f x x"
  5139 
  5140   abbreviation
  5141     neq  (infix "=!=" 50) where
  5142     "x =!= y == ~ (x === y)"
  5143 
  5144 These specifications may be also used in a locale context.  Then the
  5145 constants being introduced depend on certain fixed parameters, and the
  5146 constant name is qualified by the locale base name.  An internal
  5147 abbreviation takes care for convenient input and output, making the
  5148 parameters implicit and using the original short name.  See also
  5149 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  5150 entities from a monomorphic theory.
  5151 
  5152 Presently, abbreviations are only available 'in' a target locale, but
  5153 not inherited by general import expressions.  Also note that
  5154 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  5155 'translations' in common applications.  The "no_abbrevs" print mode
  5156 prevents folding of abbreviations in term output.
  5157 
  5158 Concrete syntax is attached to specified constants in internal form,
  5159 independently of name spaces.  The parse tree representation is
  5160 slightly different -- use 'notation' instead of raw 'syntax', and
  5161 'translations' with explicit "CONST" markup to accommodate this.
  5162 
  5163 * Pure/Isar: unified syntax for new-style specification mechanisms
  5164 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  5165 full type inference and dummy patterns ("_").  For example:
  5166 
  5167   definition "K x _ = x"
  5168 
  5169   inductive conj for A B
  5170   where "A ==> B ==> conj A B"
  5171 
  5172 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  5173 the current context.  Print mode "no_abbrevs" prevents inversion of
  5174 abbreviations on output.
  5175 
  5176 * Isar/locales: improved parameter handling: use of locales "var" and
  5177 "struct" no longer necessary; - parameter renamings are no longer
  5178 required to be injective.  For example, this allows to define
  5179 endomorphisms as locale endom = homom mult mult h.
  5180 
  5181 * Isar/locales: changed the way locales with predicates are defined.
  5182 Instead of accumulating the specification, the imported expression is
  5183 now an interpretation.  INCOMPATIBILITY: different normal form of
  5184 locale expressions.  In particular, in interpretations of locales with
  5185 predicates, goals repesenting already interpreted fragments are not
  5186 removed automatically.  Use methods `intro_locales' and
  5187 `unfold_locales'; see below.
  5188 
  5189 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  5190 provide backward reasoning on locales predicates.  The methods are
  5191 aware of interpretations and discharge corresponding goals.
  5192 `intro_locales' is less aggressive then `unfold_locales' and does not
  5193 unfold predicates to assumptions.
  5194 
  5195 * Isar/locales: the order in which locale fragments are accumulated
  5196 has changed.  This enables to override declarations from fragments due
  5197 to interpretations -- for example, unwanted simp rules.
  5198 
  5199 * Isar/locales: interpretation in theories and proof contexts has been
  5200 extended.  One may now specify (and prove) equations, which are
  5201 unfolded in interpreted theorems.  This is useful for replacing
  5202 defined concepts (constants depending on locale parameters) by
  5203 concepts already existing in the target context.  Example:
  5204 
  5205   interpretation partial_order ["op <= :: [int, int] => bool"]
  5206     where "partial_order.less (op <=) (x::int) y = (x < y)"
  5207 
  5208 Typically, the constant `partial_order.less' is created by a
  5209 definition specification element in the context of locale
  5210 partial_order.
  5211 
  5212 * Method "induct": improved internal context management to support
  5213 local fixes and defines on-the-fly. Thus explicit meta-level
  5214 connectives !!  and ==> are rarely required anymore in inductive goals
  5215 (using object-logic connectives for this purpose has been long
  5216 obsolete anyway). Common proof patterns are explained in
  5217 src/HOL/Induct/Common_Patterns.thy, see also
  5218 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  5219 examples.
  5220 
  5221 * Method "induct": improved handling of simultaneous goals. Instead of
  5222 introducing object-level conjunction, the statement is now split into
  5223 several conclusions, while the corresponding symbolic cases are nested
  5224 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  5225 see src/HOL/Induct/Common_Patterns.thy, for example.
  5226 
  5227 * Method "induct": mutual induction rules are now specified as a list
  5228 of rule sharing the same induction cases. HOL packages usually provide
  5229 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  5230 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  5231 mutual induction rules differently, i.e. like this:
  5232 
  5233   (induct rule: foo_bar.inducts)
  5234   (induct set: foo bar)
  5235   (induct pred: foo bar)
  5236   (induct type: foo bar)
  5237 
  5238 The ML function ProjectRule.projections turns old-style rules into the
  5239 new format.
  5240 
  5241 * Method "coinduct": dual of induction, see
  5242 src/HOL/Library/Coinductive_List.thy for various examples.
  5243 
  5244 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  5245 considered a legacy feature.
  5246 
  5247 * Attribute "symmetric" produces result with standardized schematic
  5248 variables (index 0).  Potential INCOMPATIBILITY.
  5249 
  5250 * Simplifier: by default the simplifier trace only shows top level
  5251 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  5252 default. Thus there is less danger of being flooded by the trace. The
  5253 trace indicates where parts have been suppressed.
  5254   
  5255 * Provers/classical: removed obsolete classical version of elim_format
  5256 attribute; classical elim/dest rules are now treated uniformly when
  5257 manipulating the claset.
  5258 
  5259 * Provers/classical: stricter checks to ensure that supplied intro,
  5260 dest and elim rules are well-formed; dest and elim rules must have at
  5261 least one premise.
  5262 
  5263 * Provers/classical: attributes dest/elim/intro take an optional
  5264 weight argument for the rule (just as the Pure versions).  Weights are
  5265 ignored by automated tools, but determine the search order of single
  5266 rule steps.
  5267 
  5268 * Syntax: input syntax now supports dummy variable binding "%_. b",
  5269 where the body does not mention the bound variable.  Note that dummy
  5270 patterns implicitly depend on their context of bounds, which makes
  5271 "{_. _}" match any set comprehension as expected.  Potential
  5272 INCOMPATIBILITY -- parse translations need to cope with syntactic
  5273 constant "_idtdummy" in the binding position.
  5274 
  5275 * Syntax: removed obsolete syntactic constant "_K" and its associated
  5276 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  5277 for example "A -> B" => "Pi A (%_. B)".
  5278 
  5279 * Pure: 'class_deps' command visualizes the subclass relation, using
  5280 the graph browser tool.
  5281 
  5282 * Pure: 'print_theory' now suppresses certain internal declarations by
  5283 default; use '!' option for full details.
  5284 
  5285 
  5286 *** HOL ***
  5287 
  5288 * Method "metis" proves goals by applying the Metis general-purpose
  5289 resolution prover (see also http://gilith.com/software/metis/).
  5290 Examples are in the directory MetisExamples.  WARNING: the
  5291 Isabelle/HOL-Metis integration does not yet work properly with
  5292 multi-threading.
  5293   
  5294 * Command 'sledgehammer' invokes external automatic theorem provers as
  5295 background processes.  It generates calls to the "metis" method if
  5296 successful. These can be pasted into the proof.  Users do not have to
  5297 wait for the automatic provers to return.  WARNING: does not really
  5298 work with multi-threading.
  5299 
  5300 * New "auto_quickcheck" feature tests outermost goal statements for
  5301 potential counter-examples.  Controlled by ML references
  5302 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  5303 5000 milliseconds).  Fails silently if statements is outside of
  5304 executable fragment, or any other codgenerator problem occurs.
  5305 
  5306 * New constant "undefined" with axiom "undefined x = undefined".
  5307 
  5308 * Added class "HOL.eq", allowing for code generation with polymorphic
  5309 equality.
  5310 
  5311 * Some renaming of class constants due to canonical name prefixing in
  5312 the new 'class' package:
  5313 
  5314     HOL.abs ~> HOL.abs_class.abs
  5315     HOL.divide ~> HOL.divide_class.divide
  5316     0 ~> HOL.zero_class.zero
  5317     1 ~> HOL.one_class.one
  5318     op + ~> HOL.plus_class.plus
  5319     op - ~> HOL.minus_class.minus
  5320     uminus ~> HOL.minus_class.uminus
  5321     op * ~> HOL.times_class.times
  5322     op < ~> HOL.ord_class.less
  5323     op <= > HOL.ord_class.less_eq
  5324     Nat.power ~> Power.power_class.power
  5325     Nat.size ~> Nat.size_class.size
  5326     Numeral.number_of ~> Numeral.number_class.number_of
  5327     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  5328     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  5329     Orderings.min ~> Orderings.ord_class.min
  5330     Orderings.max ~> Orderings.ord_class.max
  5331     Divides.op div ~> Divides.div_class.div
  5332     Divides.op mod ~> Divides.div_class.mod
  5333     Divides.op dvd ~> Divides.div_class.dvd
  5334 
  5335 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  5336 
  5337 a) User-defined constants using any of the names "plus", "minus",
  5338 "times", "less" or "less_eq". The standard syntax translations for
  5339 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  5340 names.
  5341 
  5342 b) Variables named "plus", "minus", "times", "less", "less_eq"
  5343 INCOMPATIBILITY: use more specific names.
  5344 
  5345 c) Permutative equations (e.g. "a + b = b + a")
  5346 Since the change of names also changes the order of terms, permutative
  5347 rewrite rules may get applied in a different order. Experience shows
  5348 that this is rarely the case (only two adaptions in the whole Isabelle
  5349 distribution).  INCOMPATIBILITY: rewrite proofs
  5350 
  5351 d) ML code directly refering to constant names
  5352 This in general only affects hand-written proof tactics, simprocs and
  5353 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  5354 Consider using @{const_name} antiquotation.
  5355 
  5356 * New class "default" with associated constant "default".
  5357 
  5358 * Function "sgn" is now overloaded and available on int, real, complex
  5359 (and other numeric types), using class "sgn".  Two possible defs of
  5360 sgn are given as equational assumptions in the classes sgn_if and
  5361 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  5362 INCOMPATIBILITY.
  5363 
  5364 * Locale "partial_order" now unified with class "order" (cf. theory
  5365 Orderings), added parameter "less".  INCOMPATIBILITY.
  5366 
  5367 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  5368 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  5369 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  5370 
  5371 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  5372 changed order of proof goals in instance proofs.
  5373 
  5374 * The transitivity reasoner for partial and linear orders is set up
  5375 for classes "order" and "linorder".  Instances of the reasoner are available
  5376 in all contexts importing or interpreting the corresponding locales.
  5377 Method "order" invokes the reasoner separately; the reasoner
  5378 is also integrated with the Simplifier as a solver.  Diagnostic
  5379 command 'print_orders' shows the available instances of the reasoner
  5380 in the current context.
  5381 
  5382 * Localized monotonicity predicate in theory "Orderings"; integrated
  5383 lemmas max_of_mono and min_of_mono with this predicate.
  5384 INCOMPATIBILITY.
  5385 
  5386 * Formulation of theorem "dense" changed slightly due to integration
  5387 with new class dense_linear_order.
  5388 
  5389 * Uniform lattice theory development in HOL.
  5390 
  5391     constants "meet" and "join" now named "inf" and "sup"
  5392     constant "Meet" now named "Inf"
  5393 
  5394     classes "meet_semilorder" and "join_semilorder" now named
  5395       "lower_semilattice" and "upper_semilattice"
  5396     class "lorder" now named "lattice"
  5397     class "comp_lat" now named "complete_lattice"
  5398 
  5399     Instantiation of lattice classes allows explicit definitions
  5400     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  5401 
  5402   INCOMPATIBILITY.  Theorem renames:
  5403 
  5404     meet_left_le            ~> inf_le1
  5405     meet_right_le           ~> inf_le2
  5406     join_left_le            ~> sup_ge1
  5407     join_right_le           ~> sup_ge2
  5408     meet_join_le            ~> inf_sup_ord
  5409     le_meetI                ~> le_infI
  5410     join_leI                ~> le_supI
  5411     le_meet                 ~> le_inf_iff
  5412     le_join                 ~> ge_sup_conv
  5413     meet_idempotent         ~> inf_idem
  5414     join_idempotent         ~> sup_idem
  5415     meet_comm               ~> inf_commute
  5416     join_comm               ~> sup_commute
  5417     meet_leI1               ~> le_infI1
  5418     meet_leI2               ~> le_infI2
  5419     le_joinI1               ~> le_supI1
  5420     le_joinI2               ~> le_supI2
  5421     meet_assoc              ~> inf_assoc
  5422     join_assoc              ~> sup_assoc
  5423     meet_left_comm          ~> inf_left_commute
  5424     meet_left_idempotent    ~> inf_left_idem
  5425     join_left_comm          ~> sup_left_commute
  5426     join_left_idempotent    ~> sup_left_idem
  5427     meet_aci                ~> inf_aci
  5428     join_aci                ~> sup_aci
  5429     le_def_meet             ~> le_iff_inf
  5430     le_def_join             ~> le_iff_sup
  5431     join_absorp2            ~> sup_absorb2
  5432     join_absorp1            ~> sup_absorb1
  5433     meet_absorp1            ~> inf_absorb1
  5434     meet_absorp2            ~> inf_absorb2
  5435     meet_join_absorp        ~> inf_sup_absorb
  5436     join_meet_absorp        ~> sup_inf_absorb
  5437     distrib_join_le         ~> distrib_sup_le
  5438     distrib_meet_le         ~> distrib_inf_le
  5439 
  5440     add_meet_distrib_left   ~> add_inf_distrib_left
  5441     add_join_distrib_left   ~> add_sup_distrib_left
  5442     is_join_neg_meet        ~> is_join_neg_inf
  5443     is_meet_neg_join        ~> is_meet_neg_sup
  5444     add_meet_distrib_right  ~> add_inf_distrib_right
  5445     add_join_distrib_right  ~> add_sup_distrib_right
  5446     add_meet_join_distribs  ~> add_sup_inf_distribs
  5447     join_eq_neg_meet        ~> sup_eq_neg_inf
  5448     meet_eq_neg_join        ~> inf_eq_neg_sup
  5449     add_eq_meet_join        ~> add_eq_inf_sup
  5450     meet_0_imp_0            ~> inf_0_imp_0
  5451     join_0_imp_0            ~> sup_0_imp_0
  5452     meet_0_eq_0             ~> inf_0_eq_0
  5453     join_0_eq_0             ~> sup_0_eq_0
  5454     neg_meet_eq_join        ~> neg_inf_eq_sup
  5455     neg_join_eq_meet        ~> neg_sup_eq_inf
  5456     join_eq_if              ~> sup_eq_if
  5457 
  5458     mono_meet               ~> mono_inf
  5459     mono_join               ~> mono_sup
  5460     meet_bool_eq            ~> inf_bool_eq
  5461     join_bool_eq            ~> sup_bool_eq
  5462     meet_fun_eq             ~> inf_fun_eq
  5463     join_fun_eq             ~> sup_fun_eq
  5464     meet_set_eq             ~> inf_set_eq
  5465     join_set_eq             ~> sup_set_eq
  5466     meet1_iff               ~> inf1_iff
  5467     meet2_iff               ~> inf2_iff
  5468     meet1I                  ~> inf1I
  5469     meet2I                  ~> inf2I
  5470     meet1D1                 ~> inf1D1
  5471     meet2D1                 ~> inf2D1
  5472     meet1D2                 ~> inf1D2
  5473     meet2D2                 ~> inf2D2
  5474     meet1E                  ~> inf1E
  5475     meet2E                  ~> inf2E
  5476     join1_iff               ~> sup1_iff
  5477     join2_iff               ~> sup2_iff
  5478     join1I1                 ~> sup1I1
  5479     join2I1                 ~> sup2I1
  5480     join1I1                 ~> sup1I1
  5481     join2I2                 ~> sup1I2
  5482     join1CI                 ~> sup1CI
  5483     join2CI                 ~> sup2CI
  5484     join1E                  ~> sup1E
  5485     join2E                  ~> sup2E
  5486 
  5487     is_meet_Meet            ~> is_meet_Inf
  5488     Meet_bool_def           ~> Inf_bool_def
  5489     Meet_fun_def            ~> Inf_fun_def
  5490     Meet_greatest           ~> Inf_greatest
  5491     Meet_lower              ~> Inf_lower
  5492     Meet_set_def            ~> Inf_set_def
  5493 
  5494     Sup_def                 ~> Sup_Inf
  5495     Sup_bool_eq             ~> Sup_bool_def
  5496     Sup_fun_eq              ~> Sup_fun_def
  5497     Sup_set_eq              ~> Sup_set_def
  5498 
  5499     listsp_meetI            ~> listsp_infI
  5500     listsp_meet_eq          ~> listsp_inf_eq
  5501 
  5502     meet_min                ~> inf_min
  5503     join_max                ~> sup_max
  5504 
  5505 * Added syntactic class "size"; overloaded constant "size" now has
  5506 type "'a::size ==> bool"
  5507 
  5508 * Internal reorganisation of `size' of datatypes: size theorems
  5509 "foo.size" are no longer subsumed by "foo.simps" (but are still
  5510 simplification rules by default!); theorems "prod.size" now named
  5511 "*.size".
  5512 
  5513 * Class "div" now inherits from class "times" rather than "type".
  5514 INCOMPATIBILITY.
  5515 
  5516 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  5517 Linorder etc.  have disappeared; operations defined in terms of
  5518 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  5519 
  5520 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  5521 
  5522 * HOL-Word: New extensive library and type for generic, fixed size
  5523 machine words, with arithmetic, bit-wise, shifting and rotating
  5524 operations, reflection into int, nat, and bool lists, automation for
  5525 linear arithmetic (by automatic reflection into nat or int), including
  5526 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  5527 arithmetic type classes, supporting automatic simplification of
  5528 numerals on all operations.
  5529 
  5530 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  5531 
  5532 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  5533 
  5534 * Code generator library theories:
  5535   - Code_Integer represents HOL integers by big integer literals in target
  5536     languages.
  5537   - Code_Char represents HOL characters by character literals in target
  5538     languages.
  5539   - Code_Char_chr like Code_Char, but also offers treatment of character
  5540     codes; includes Code_Integer.
  5541   - Executable_Set allows to generate code for finite sets using lists.
  5542   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  5543     denominator).
  5544   - Executable_Real implements a subset of real numbers, namly those
  5545     representable by rational numbers.
  5546   - Efficient_Nat implements natural numbers by integers, which in general will
  5547     result in higher efficency; pattern matching with 0/Suc is eliminated;
  5548     includes Code_Integer.
  5549   - Code_Index provides an additional datatype index which is mapped to
  5550     target-language built-in integers.
  5551   - Code_Message provides an additional datatype message_string which is isomorphic to
  5552     strings; messages are mapped to target-language strings.
  5553 
  5554 * New package for inductive predicates
  5555 
  5556   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  5557 
  5558     inductive
  5559       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5560       for z_1 :: U_1 and ... and z_n :: U_m
  5561     where
  5562       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5563     | ...
  5564 
  5565   with full support for type-inference, rather than
  5566 
  5567     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5568 
  5569     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5570     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5571 
  5572     inductive "s z_1 ... z_m"
  5573     intros
  5574       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5575       ...
  5576 
  5577   For backward compatibility, there is a wrapper allowing inductive
  5578   sets to be defined with the new package via
  5579 
  5580     inductive_set
  5581       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5582       for z_1 :: U_1 and ... and z_n :: U_m
  5583     where
  5584       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5585     | ...
  5586 
  5587   or
  5588 
  5589     inductive_set
  5590       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5591       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5592       for z_1 :: U_1 and ... and z_n :: U_m
  5593     where
  5594       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5595     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5596     | ...
  5597 
  5598   if the additional syntax "p ..." is required.
  5599 
  5600   Numerous examples can be found in the subdirectories src/HOL/Auth,
  5601   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  5602 
  5603   INCOMPATIBILITIES:
  5604 
  5605   - Since declaration and definition of inductive sets or predicates
  5606     is no longer separated, abbreviations involving the newly
  5607     introduced sets or predicates must be specified together with the
  5608     introduction rules after the 'where' keyword (see above), rather
  5609     than before the actual inductive definition.
  5610 
  5611   - The variables in induction and elimination rules are now
  5612     quantified in the order of their occurrence in the introduction
  5613     rules, rather than in alphabetical order. Since this may break
  5614     some proofs, these proofs either have to be repaired, e.g. by
  5615     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  5616     statements of the form
  5617 
  5618       case (rule_i a_i_1 ... a_i_{k_i})
  5619 
  5620     or the old order of quantification has to be restored by explicitly adding
  5621     meta-level quantifiers in the introduction rules, i.e.
  5622 
  5623       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  5624 
  5625   - The format of the elimination rules is now
  5626 
  5627       p z_1 ... z_m x_1 ... x_n ==>
  5628         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5629         ==> ... ==> P
  5630 
  5631     for predicates and
  5632 
  5633       (x_1, ..., x_n) : s z_1 ... z_m ==>
  5634         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5635         ==> ... ==> P
  5636 
  5637     for sets rather than
  5638 
  5639       x : s z_1 ... z_m ==>
  5640         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  5641         ==> ... ==> P
  5642 
  5643     This may require terms in goals to be expanded to n-tuples
  5644     (e.g. using case_tac or simplification with the split_paired_all
  5645     rule) before the above elimination rule is applicable.
  5646 
  5647   - The elimination or case analysis rules for (mutually) inductive
  5648     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  5649     list of rules "p_1_..._p_k.elims" is no longer available.
  5650 
  5651 * New package "function"/"fun" for general recursive functions,
  5652 supporting mutual and nested recursion, definitions in local contexts,
  5653 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  5654 for small examples, and the separate tutorial on the function
  5655 package. The old recdef "package" is still available as before, but
  5656 users are encouraged to use the new package.
  5657 
  5658 * Method "lexicographic_order" automatically synthesizes termination
  5659 relations as lexicographic combinations of size measures. 
  5660 
  5661 * Case-expressions allow arbitrary constructor-patterns (including
  5662 "_") and take their order into account, like in functional
  5663 programming.  Internally, this is translated into nested
  5664 case-expressions; missing cases are added and mapped to the predefined
  5665 constant "undefined". In complicated cases printing may no longer show
  5666 the original input but the internal form. Lambda-abstractions allow
  5667 the same form of pattern matching: "% pat1 => e1 | ..." is an
  5668 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  5669 variable.
  5670 
  5671 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  5672 is an abbreviation for "of_nat :: nat => int". The simplification
  5673 rules for "of_nat" have been changed to work like "int" did
  5674 previously.  Potential INCOMPATIBILITY:
  5675   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  5676   - of_nat_diff and of_nat_mult are no longer default simp rules
  5677 
  5678 * Method "algebra" solves polynomial equations over (semi)rings using
  5679 Groebner bases. The (semi)ring structure is defined by locales and the
  5680 tool setup depends on that generic context. Installing the method for
  5681 a specific type involves instantiating the locale and possibly adding
  5682 declarations for computation on the coefficients.  The method is
  5683 already instantiated for natural numbers and for the axiomatic class
  5684 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  5685 CALCULEMUS 2007 for the general principles underlying this
  5686 architecture of context-aware proof-tools.
  5687 
  5688 * Method "ferrack" implements quantifier elimination over
  5689 special-purpose dense linear orders using locales (analogous to
  5690 "algebra"). The method is already installed for class
  5691 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  5692 rat, etc.
  5693 
  5694 * Former constant "List.op @" now named "List.append".  Use ML
  5695 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  5696 circumvent possible incompatibilities when working on ML level.
  5697 
  5698 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  5699 
  5700 * New function listsum :: 'a list => 'a for arbitrary monoids.
  5701 Special syntax: "SUM x <- xs. f x" (and latex variants)
  5702 
  5703 * New syntax for Haskell-like list comprehension (input only), eg.
  5704 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  5705 
  5706 * The special syntax for function "filter" has changed from [x :
  5707 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  5708 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  5709 
  5710 * [a..b] is now defined for arbitrary linear orders.  It used to be
  5711 defined on nat only, as an abbreviation for [a..<Suc b]
  5712 INCOMPATIBILITY.
  5713 
  5714 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  5715 
  5716 * New functions "sorted" and "sort" in src/HOL/List.thy.
  5717 
  5718 * New lemma collection field_simps (an extension of ring_simps) for
  5719 manipulating (in)equations involving division. Multiplies with all
  5720 denominators that can be proved to be non-zero (in equations) or
  5721 positive/negative (in inequations).
  5722 
  5723 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  5724 have been improved and renamed to ring_simps, group_simps and
  5725 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  5726 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  5727 
  5728 * Theory Library/Commutative_Ring: switched from recdef to function
  5729 package; constants add, mul, pow now curried.  Infix syntax for
  5730 algebraic operations.
  5731 
  5732 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  5733 INCOMPATIBILITY.
  5734 
  5735 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  5736 INCOMPATIBILITY.
  5737 
  5738 * HOL/records: generalised field-update to take a function on the
  5739 field rather than the new value: r(|A := x|) is translated to A_update
  5740 (K x) r The K-combinator that is internally used is called K_record.
  5741 INCOMPATIBILITY: Usage of the plain update functions has to be
  5742 adapted.
  5743  
  5744 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  5745 * x = 0, which are required for a semiring.  Richer structures do not
  5746 inherit from semiring_0 anymore, because this property is a theorem
  5747 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  5748 there is more to prove, but this is mostly trivial.
  5749 
  5750 * Class "recpower" is generalized to arbitrary monoids, not just
  5751 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  5752 commutativity or semiring properties additionally.
  5753 
  5754 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  5755 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  5756 better use 'abbreviation'.
  5757 
  5758 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  5759 
  5760 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  5761 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  5762 significant changes for setting up numeral syntax for types:
  5763   - New constants Numeral.pred and Numeral.succ instead
  5764       of former Numeral.bin_pred and Numeral.bin_succ.
  5765   - Use integer operations instead of bin_add, bin_mult and so on.
  5766   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  5767   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  5768 
  5769 See src/HOL/Integ/IntArith.thy for an example setup.
  5770 
  5771 * Command 'normal_form' computes the normal form of a term that may
  5772 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  5773 produces ``[b, c, a]'' (without proof).  This command is suitable for
  5774 heavy-duty computations because the functions are compiled to ML
  5775 first.  Correspondingly, a method "normalization" is provided.  See
  5776 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  5777 
  5778 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  5779 25 like -->); output depends on the "iff" print_mode, the default is
  5780 "A = B" (with priority 50).
  5781 
  5782 * Relations less (<) and less_eq (<=) are also available on type bool.
  5783 Modified syntax to disallow nesting without explicit parentheses,
  5784 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  5785 INCOMPATIBILITY.
  5786 
  5787 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  5788 
  5789 * Relation composition operator "op O" now has precedence 75 and binds
  5790 stronger than union and intersection. INCOMPATIBILITY.
  5791 
  5792 * The old set interval syntax "{m..n(}" (and relatives) has been
  5793 removed.  Use "{m..<n}" (and relatives) instead.
  5794 
  5795 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  5796 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  5797 ``declare [[simproc del: neq]]''.
  5798 
  5799 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  5800 True/False.
  5801 
  5802 * Theorem Cons_eq_map_conv no longer declared as "simp".
  5803 
  5804 * Theorem setsum_mult renamed to setsum_right_distrib.
  5805 
  5806 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  5807 ``rule'' method.
  5808 
  5809 * Reimplemented methods "sat" and "satx", with several improvements:
  5810 goals no longer need to be stated as "<prems> ==> False", equivalences
  5811 (i.e. "=" on type bool) are handled, variable names of the form
  5812 "lit_<n>" are no longer reserved, significant speedup.
  5813 
  5814 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  5815 zChaff is still supported as well.
  5816 
  5817 * 'inductive' and 'datatype': provide projections of mutual rules,
  5818 bundled as foo_bar.inducts;
  5819 
  5820 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  5821 Library.
  5822 
  5823 * Library: moved theory Accessible_Part to main HOL.
  5824 
  5825 * Library: added theory Coinductive_List of potentially infinite lists
  5826 as greatest fixed-point.
  5827 
  5828 * Library: added theory AssocList which implements (finite) maps as
  5829 association lists.
  5830 
  5831 * Method "evaluation" solves goals (i.e. a boolean expression)
  5832 efficiently by compiling it to ML.  The goal is "proved" (via an
  5833 oracle) if it evaluates to True.
  5834 
  5835 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  5836 also when invoked by the simplifier.  This results in the Simplifier
  5837 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  5838 Configuration option fast_arith_split_limit=0 recovers the old
  5839 behavior.
  5840 
  5841 * Support for hex (0x20) and binary (0b1001) numerals.
  5842 
  5843 * New method: reify eqs (t), where eqs are equations for an
  5844 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  5845 parameter, computes a term s::'b and a list xs::'a list and proves the
  5846 theorem I xs s = t. This is also known as reification or quoting. The
  5847 resulting theorem is applied to the subgoal to substitute t with I xs
  5848 s.  If t is omitted, the subgoal itself is reified.
  5849 
  5850 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  5851 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  5852 where f is supposed to be a computable function (in the sense of code
  5853 generattion). The method uses reify to compute s and xs as above then
  5854 applies corr_thm and uses normalization by evaluation to "prove" f s =
  5855 r and finally gets the theorem t = r, which is again applied to the
  5856 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  5857 
  5858 * Reflection: Automatic reification now handels binding, an example is
  5859 available in src/HOL/ex/ReflectionEx.thy
  5860 
  5861 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  5862 command 'statespace' that is similar to 'record', but introduces an
  5863 abstract specification based on the locale infrastructure instead of
  5864 HOL types.  This leads to extra flexibility in composing state spaces,
  5865 in particular multiple inheritance and renaming of components.
  5866 
  5867 
  5868 *** HOL-Complex ***
  5869 
  5870 * Hyperreal: Functions root and sqrt are now defined on negative real
  5871 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  5872 Nonnegativity side conditions have been removed from many lemmas, so
  5873 that more subgoals may now be solved by simplification; potential
  5874 INCOMPATIBILITY.
  5875 
  5876 * Real: new type classes formalize real normed vector spaces and
  5877 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  5878 and norm :: 'a => real.
  5879 
  5880 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  5881 reals into other types. The overloaded constant Reals :: 'a set is now
  5882 defined as range of_real; potential INCOMPATIBILITY.
  5883 
  5884 * Real: proper support for ML code generation, including 'quickcheck'.
  5885 Reals are implemented as arbitrary precision rationals.
  5886 
  5887 * Hyperreal: Several constants that previously worked only for the
  5888 reals have been generalized, so they now work over arbitrary vector
  5889 spaces. Type annotations may need to be added in some cases; potential
  5890 INCOMPATIBILITY.
  5891 
  5892   Infinitesimal  :: ('a::real_normed_vector) star set
  5893   HFinite        :: ('a::real_normed_vector) star set
  5894   HInfinite      :: ('a::real_normed_vector) star set
  5895   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5896   monad          :: ('a::real_normed_vector) star => 'a star set
  5897   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5898   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5899   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5900   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5901   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5902   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5903   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5904   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5905   sgn            :: 'a::real_normed_vector => 'a
  5906   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5907 
  5908 * Complex: Some complex-specific constants are now abbreviations for
  5909 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5910 hnorm.  Other constants have been entirely removed in favor of the
  5911 polymorphic versions (INCOMPATIBILITY):
  5912 
  5913   approx        <-- capprox
  5914   HFinite       <-- CFinite
  5915   HInfinite     <-- CInfinite
  5916   Infinitesimal <-- CInfinitesimal
  5917   monad         <-- cmonad
  5918   galaxy        <-- cgalaxy
  5919   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5920   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5921   (ns)deriv     <-- (ns)cderiv
  5922 
  5923 
  5924 *** HOL-Algebra ***
  5925 
  5926 * Formalisation of ideals and the quotient construction over rings.
  5927 
  5928 * Order and lattice theory no longer based on records.
  5929 INCOMPATIBILITY.
  5930 
  5931 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5932 greatest_closed.  INCOMPATIBILITY.
  5933 
  5934 * Method algebra is now set up via an attribute.  For examples see
  5935 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5936 of algebraic structures.
  5937 
  5938 * Renamed theory CRing to Ring.
  5939 
  5940 
  5941 *** HOL-Nominal ***
  5942 
  5943 * Substantial, yet incomplete support for nominal datatypes (binding
  5944 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5945 src/HOL/Nominal/Examples.  Prospective users should consult
  5946 http://isabelle.in.tum.de/nominal/
  5947 
  5948 
  5949 *** ML ***
  5950 
  5951 * ML basics: just one true type int, which coincides with IntInf.int
  5952 (even on SML/NJ).
  5953 
  5954 * ML within Isar: antiquotations allow to embed statically-checked
  5955 formal entities in the source, referring to the context available at
  5956 compile-time.  For example:
  5957 
  5958 ML {* @{sort "{zero,one}"} *}
  5959 ML {* @{typ "'a => 'b"} *}
  5960 ML {* @{term "%x. x"} *}
  5961 ML {* @{prop "x == y"} *}
  5962 ML {* @{ctyp "'a => 'b"} *}
  5963 ML {* @{cterm "%x. x"} *}
  5964 ML {* @{cprop "x == y"} *}
  5965 ML {* @{thm asm_rl} *}
  5966 ML {* @{thms asm_rl} *}
  5967 ML {* @{type_name c} *}
  5968 ML {* @{type_syntax c} *}
  5969 ML {* @{const_name c} *}
  5970 ML {* @{const_syntax c} *}
  5971 ML {* @{context} *}
  5972 ML {* @{theory} *}
  5973 ML {* @{theory Pure} *}
  5974 ML {* @{theory_ref} *}
  5975 ML {* @{theory_ref Pure} *}
  5976 ML {* @{simpset} *}
  5977 ML {* @{claset} *}
  5978 ML {* @{clasimpset} *}
  5979 
  5980 The same works for sources being ``used'' within an Isar context.
  5981 
  5982 * ML in Isar: improved error reporting; extra verbosity with
  5983 ML_Context.trace enabled.
  5984 
  5985 * Pure/General/table.ML: the join operations now works via exceptions
  5986 DUP/SAME instead of type option. This is simpler in simple cases, and
  5987 admits slightly more efficient complex applications.
  5988 
  5989 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5990 use Context.generic instead of just theory.
  5991 
  5992 * Pure: datatype Context.generic joins theory/Proof.context and
  5993 provides some facilities for code that works in either kind of
  5994 context, notably GenericDataFun for uniform theory and proof data.
  5995 
  5996 * Pure: simplified internal attribute type, which is now always
  5997 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5998 local (Proof.context) attributes have been discontinued, while
  5999 minimizing code duplication. Thm.rule_attribute and
  6000 Thm.declaration_attribute build canonical attributes; see also structure
  6001 Context for further operations on Context.generic, notably
  6002 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  6003 declarations and definitions.
  6004 
  6005 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  6006 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  6007 init only required for impure data. INCOMPATIBILITY: empty really need
  6008 to be empty (no dependencies on theory content!)
  6009 
  6010 * Pure/kernel: consts certification ignores sort constraints given in
  6011 signature declarations. (This information is not relevant to the
  6012 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  6013 potential INCOMPATIBILITY.
  6014 
  6015 * Pure: axiomatic type classes are now purely definitional, with
  6016 explicit proofs of class axioms and super class relations performed
  6017 internally. See Pure/axclass.ML for the main internal interfaces --
  6018 notably AxClass.define_class supercedes AxClass.add_axclass, and
  6019 AxClass.axiomatize_class/classrel/arity supersede
  6020 Sign.add_classes/classrel/arities.
  6021 
  6022 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  6023 global/local versions on theory vs. Proof.context have been
  6024 discontinued; Attrib.syntax and Method.syntax have been adapted
  6025 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  6026 attributes, methods, etc.
  6027 
  6028 * Pure: several functions of signature "... -> theory -> theory * ..."
  6029 have been reoriented to "... -> theory -> ... * theory" in order to
  6030 allow natural usage in combination with the ||>, ||>>, |-> and
  6031 fold_map combinators.
  6032 
  6033 * Pure: official theorem names (closed derivations) and additional
  6034 comments (tags) are now strictly separate.  Name hints -- which are
  6035 maintained as tags -- may be attached any time without affecting the
  6036 derivation.
  6037 
  6038 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  6039 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  6040 achieve the old behaviour.
  6041 
  6042 * Pure: the "Goal" constant is now called "prop", supporting a
  6043 slightly more general idea of ``protecting'' meta-level rule
  6044 statements.
  6045 
  6046 * Pure: Logic.(un)varify only works in a global context, which is now
  6047 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  6048 Logic.legacy_(un)varify as temporary workaround.
  6049 
  6050 * Pure: structure Name provides scalable operations for generating
  6051 internal variable names, notably Name.variants etc.  This replaces
  6052 some popular functions from term.ML:
  6053 
  6054   Term.variant		->  Name.variant
  6055   Term.variantlist	->  Name.variant_list
  6056   Term.invent_names	->  Name.invent_list
  6057 
  6058 Note that low-level renaming rarely occurs in new code -- operations
  6059 from structure Variable are used instead (see below).
  6060 
  6061 * Pure: structure Variable provides fundamental operations for proper
  6062 treatment of fixed/schematic variables in a context.  For example,
  6063 Variable.import introduces fixes for schematics of given facts and
  6064 Variable.export reverses the effect (up to renaming) -- this replaces
  6065 various freeze_thaw operations.
  6066 
  6067 * Pure: structure Goal provides simple interfaces for
  6068 init/conclude/finish and tactical prove operations (replacing former
  6069 Tactic.prove).  Goal.prove is the canonical way to prove results
  6070 within a given context; Goal.prove_global is a degraded version for
  6071 theory level goals, including a global Drule.standard.  Note that
  6072 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  6073 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  6074 in a locale context).
  6075 
  6076 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  6077 and type checking (Syntax.check_term etc.), with common combinations
  6078 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  6079 which are considered legacy and await removal.
  6080 
  6081 * Pure/Syntax: generic interfaces for type unchecking
  6082 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  6083 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  6084 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  6085 available for convenience, but refer to the very same operations using
  6086 a mere theory instead of a full context.
  6087 
  6088 * Isar: simplified treatment of user-level errors, using exception
  6089 ERROR of string uniformly.  Function error now merely raises ERROR,
  6090 without any side effect on output channels.  The Isar toplevel takes
  6091 care of proper display of ERROR exceptions.  ML code may use plain
  6092 handle/can/try; cat_error may be used to concatenate errors like this:
  6093 
  6094   ... handle ERROR msg => cat_error msg "..."
  6095 
  6096 Toplevel ML code (run directly or through the Isar toplevel) may be
  6097 embedded into the Isar toplevel with exception display/debug like
  6098 this:
  6099 
  6100   Isar.toplevel (fn () => ...)
  6101 
  6102 INCOMPATIBILITY, removed special transform_error facilities, removed
  6103 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  6104 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  6105 -- use plain ERROR instead.
  6106 
  6107 * Isar: theory setup now has type (theory -> theory), instead of a
  6108 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  6109 
  6110 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  6111 ProofContext.debug/verbose flags.
  6112 
  6113 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  6114 theory before entering a proof state.  Transactions now always see a
  6115 quasi-functional intermediate checkpoint, both in interactive and
  6116 batch mode.
  6117 
  6118 * Isar: simplified interfaces for outer syntax.  Renamed
  6119 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  6120 OuterSyntax.add_parsers -- this functionality is now included in
  6121 OuterSyntax.command etc.  INCOMPATIBILITY.
  6122 
  6123 * Simplifier: the simpset of a running simplification process now
  6124 contains a proof context (cf. Simplifier.the_context), which is the
  6125 very context that the initial simpset has been retrieved from (by
  6126 simpset_of/local_simpset_of).  Consequently, all plug-in components
  6127 (solver, looper etc.) may depend on arbitrary proof data.
  6128 
  6129 * Simplifier.inherit_context inherits the proof context (plus the
  6130 local bounds) of the current simplification process; any simproc
  6131 etc. that calls the Simplifier recursively should do this!  Removed
  6132 former Simplifier.inherit_bounds, which is already included here --
  6133 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  6134 specify an explicit context using Simplifier.context/theory_context.
  6135 
  6136 * Simplifier/Classical Reasoner: more abstract interfaces
  6137 change_simpset/claset for modifying the simpset/claset reference of a
  6138 theory; raw versions simpset/claset_ref etc. have been discontinued --
  6139 INCOMPATIBILITY.
  6140 
  6141 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  6142 "Trueprop" etc.
  6143 
  6144 
  6145 *** System ***
  6146 
  6147 * settings: the default heap location within ISABELLE_HOME_USER now
  6148 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  6149 Isabelle installations.
  6150 
  6151 * isabelle-process: option -S (secure mode) disables some critical
  6152 operations, notably runtime compilation and evaluation of ML source
  6153 code.
  6154 
  6155 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  6156 
  6157 * Support for parallel execution, using native multicore support of
  6158 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  6159 independent theories, according to the given theory header
  6160 specifications. The maximum number of worker threads is specified via
  6161 usedir option -M or the "max-threads" setting in Proof General. A
  6162 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  6163 to 6 on a 8-core machine.  User-code needs to observe certain
  6164 guidelines for thread-safe programming, see appendix A in the Isar
  6165 Implementation manual.
  6166 
  6167 
  6168 
  6169 New in Isabelle2005 (October 2005)
  6170 ----------------------------------
  6171 
  6172 *** General ***
  6173 
  6174 * Theory headers: the new header syntax for Isar theories is
  6175 
  6176   theory <name>
  6177   imports <theory1> ... <theoryN>
  6178   uses <file1> ... <fileM>
  6179   begin
  6180 
  6181 where the 'uses' part is optional.  The previous syntax
  6182 
  6183   theory <name> = <theory1> + ... + <theoryN>:
  6184 
  6185 will disappear in the next release.  Use isatool fixheaders to convert
  6186 existing theory files.  Note that there is no change in ancient
  6187 non-Isar theories now, but these will disappear soon.
  6188 
  6189 * Theory loader: parent theories can now also be referred to via
  6190 relative and absolute paths.
  6191 
  6192 * Command 'find_theorems' searches for a list of criteria instead of a
  6193 list of constants. Known criteria are: intro, elim, dest, name:string,
  6194 simp:term, and any term. Criteria can be preceded by '-' to select
  6195 theorems that do not match. Intro, elim, dest select theorems that
  6196 match the current goal, name:s selects theorems whose fully qualified
  6197 name contain s, and simp:term selects all simplification rules whose
  6198 lhs match term.  Any other term is interpreted as pattern and selects
  6199 all theorems matching the pattern. Available in ProofGeneral under
  6200 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  6201 
  6202   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  6203 
  6204 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  6205 matching the current goal as introduction rule and not having "HOL."
  6206 in their name (i.e. not being defined in theory HOL).
  6207 
  6208 * Command 'thms_containing' has been discontinued in favour of
  6209 'find_theorems'; INCOMPATIBILITY.
  6210 
  6211 * Communication with Proof General is now 8bit clean, which means that
  6212 Unicode text in UTF-8 encoding may be used within theory texts (both
  6213 formal and informal parts).  Cf. option -U of the Isabelle Proof
  6214 General interface.  Here are some simple examples (cf. src/HOL/ex):
  6215 
  6216   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  6217   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  6218 
  6219 * Improved efficiency of the Simplifier and, to a lesser degree, the
  6220 Classical Reasoner.  Typical big applications run around 2 times
  6221 faster.
  6222 
  6223 
  6224 *** Document preparation ***
  6225 
  6226 * Commands 'display_drafts' and 'print_drafts' perform simple output
  6227 of raw sources.  Only those symbols that do not require additional
  6228 LaTeX packages (depending on comments in isabellesym.sty) are
  6229 displayed properly, everything else is left verbatim.  isatool display
  6230 and isatool print are used as front ends (these are subject to the
  6231 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  6232 
  6233 * Command tags control specific markup of certain regions of text,
  6234 notably folding and hiding.  Predefined tags include "theory" (for
  6235 theory begin and end), "proof" for proof commands, and "ML" for
  6236 commands involving ML code; the additional tags "visible" and
  6237 "invisible" are unused by default.  Users may give explicit tag
  6238 specifications in the text, e.g. ''by %invisible (auto)''.  The
  6239 interpretation of tags is determined by the LaTeX job during document
  6240 preparation: see option -V of isatool usedir, or options -n and -t of
  6241 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  6242 \isadroptag.
  6243 
  6244 Several document versions may be produced at the same time via isatool
  6245 usedir (the generated index.html will link all of them).  Typical
  6246 specifications include ''-V document=theory,proof,ML'' to present
  6247 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  6248 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  6249 these parts without any formal replacement text.  The Isabelle site
  6250 default settings produce ''document'' and ''outline'' versions as
  6251 specified above.
  6252 
  6253 * Several new antiquotations:
  6254 
  6255   @{term_type term} prints a term with its type annotated;
  6256 
  6257   @{typeof term} prints the type of a term;
  6258 
  6259   @{const const} is the same as @{term const}, but checks that the
  6260   argument is a known logical constant;
  6261 
  6262   @{term_style style term} and @{thm_style style thm} print a term or
  6263   theorem applying a "style" to it
  6264 
  6265   @{ML text}
  6266 
  6267 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  6268 definitions, equations, inequations etc., 'concl' printing only the
  6269 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  6270 to print the specified premise.  TermStyle.add_style provides an ML
  6271 interface for introducing further styles.  See also the "LaTeX Sugar"
  6272 document practical applications.  The ML antiquotation prints
  6273 type-checked ML expressions verbatim.
  6274 
  6275 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  6276 and 'text' support optional locale specification '(in loc)', which
  6277 specifies the default context for interpreting antiquotations.  For
  6278 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  6279 
  6280 * Option 'locale=NAME' of antiquotations specifies an alternative
  6281 context interpreting the subsequent argument.  For example: @{thm
  6282 [locale=lattice] inf_assoc}.
  6283 
  6284 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  6285 a proof context.
  6286 
  6287 * Proper output of antiquotations for theory commands involving a
  6288 proof context (such as 'locale' or 'theorem (in loc) ...').
  6289 
  6290 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  6291 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  6292 
  6293 * isatool usedir: new option -C (default true) controls whether option
  6294 -D should include a copy of the original document directory; -C false
  6295 prevents unwanted effects such as copying of administrative CVS data.
  6296 
  6297 
  6298 *** Pure ***
  6299 
  6300 * Considerably improved version of 'constdefs' command.  Now performs
  6301 automatic type-inference of declared constants; additional support for
  6302 local structure declarations (cf. locales and HOL records), see also
  6303 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  6304 sequential dependencies of definitions within a single 'constdefs'
  6305 section; moreover, the declared name needs to be an identifier.  If
  6306 all fails, consider to fall back on 'consts' and 'defs' separately.
  6307 
  6308 * Improved indexed syntax and implicit structures.  First of all,
  6309 indexed syntax provides a notational device for subscripted
  6310 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  6311 expressions.  Secondly, in a local context with structure
  6312 declarations, number indexes \<^sub>n or the empty index (default
  6313 number 1) refer to a certain fixed variable implicitly; option
  6314 show_structs controls printing of implicit structures.  Typical
  6315 applications of these concepts involve record types and locales.
  6316 
  6317 * New command 'no_syntax' removes grammar declarations (and
  6318 translations) resulting from the given syntax specification, which is
  6319 interpreted in the same manner as for the 'syntax' command.
  6320 
  6321 * 'Advanced' translation functions (parse_translation etc.) may depend
  6322 on the signature of the theory context being presently used for
  6323 parsing/printing, see also isar-ref manual.
  6324 
  6325 * Improved 'oracle' command provides a type-safe interface to turn an
  6326 ML expression of type theory -> T -> term into a primitive rule of
  6327 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  6328 is already included here); see also FOL/ex/IffExample.thy;
  6329 INCOMPATIBILITY.
  6330 
  6331 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  6332 before); "cI" is no longer bound, use "c.intro" instead.
  6333 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  6334 axclasses vs. locales.
  6335 
  6336 * Improved internal renaming of symbolic identifiers -- attach primes
  6337 instead of base 26 numbers.
  6338 
  6339 * New flag show_question_marks controls printing of leading question
  6340 marks in schematic variable names.
  6341 
  6342 * In schematic variable names, *any* symbol following \<^isub> or
  6343 \<^isup> is now treated as part of the base name.  For example, the
  6344 following works without printing of awkward ".0" indexes:
  6345 
  6346   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  6347     by simp
  6348 
  6349 * Inner syntax includes (*(*nested*) comments*).
  6350 
  6351 * Pretty printer now supports unbreakable blocks, specified in mixfix
  6352 annotations as "(00...)".
  6353 
  6354 * Clear separation of logical types and nonterminals, where the latter
  6355 may only occur in 'syntax' specifications or type abbreviations.
  6356 Before that distinction was only partially implemented via type class
  6357 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  6358 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  6359 exotic syntax specifications may require further adaption
  6360 (e.g. Cube/Cube.thy).
  6361 
  6362 * Removed obsolete type class "logic", use the top sort {} instead.
  6363 Note that non-logical types should be declared as 'nonterminals'
  6364 rather than 'types'.  INCOMPATIBILITY for new object-logic
  6365 specifications.
  6366 
  6367 * Attributes 'induct' and 'cases': type or set names may now be
  6368 locally fixed variables as well.
  6369 
  6370 * Simplifier: can now control the depth to which conditional rewriting
  6371 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  6372 Limit.
  6373 
  6374 * Simplifier: simplification procedures may now take the current
  6375 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  6376 interface), which is very useful for calling the Simplifier
  6377 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  6378 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  6379 low-level mk_simproc no longer applies Logic.varify internally, to
  6380 allow for use in a context of fixed variables.
  6381 
  6382 * thin_tac now works even if the assumption being deleted contains !!
  6383 or ==>.  More generally, erule now works even if the major premise of
  6384 the elimination rule contains !! or ==>.
  6385 
  6386 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  6387 
  6388 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  6389 from Pure, which contains all common declarations already.  Both
  6390 theories are defined via plain Isabelle/Isar .thy files.
  6391 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  6392 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  6393 use isatool fixcpure to adapt your theory and ML sources.
  6394 
  6395 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  6396 selections of theorems in named facts via index ranges.
  6397 
  6398 * 'print_theorems': in theory mode, really print the difference
  6399 wrt. the last state (works for interactive theory development only),
  6400 in proof mode print all local facts (cf. 'print_facts');
  6401 
  6402 * 'hide': option '(open)' hides only base names.
  6403 
  6404 * More efficient treatment of intermediate checkpoints in interactive
  6405 theory development.
  6406 
  6407 * Code generator is now invoked via code_module (incremental code
  6408 generation) and code_library (modular code generation, ML structures
  6409 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  6410 must be quoted when used as identifiers.
  6411 
  6412 * New 'value' command for reading, evaluating and printing terms using
  6413 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  6414 quoted when used as identifier.
  6415 
  6416 
  6417 *** Locales ***
  6418 
  6419 * New commands for the interpretation of locale expressions in
  6420 theories (1), locales (2) and proof contexts (3).  These generate
  6421 proof obligations from the expression specification.  After the
  6422 obligations have been discharged, theorems of the expression are added
  6423 to the theory, target locale or proof context.  The synopsis of the
  6424 commands is a follows:
  6425 
  6426   (1) interpretation expr inst
  6427   (2) interpretation target < expr
  6428   (3) interpret expr inst
  6429 
  6430 Interpretation in theories and proof contexts require a parameter
  6431 instantiation of terms from the current context.  This is applied to
  6432 specifications and theorems of the interpreted expression.
  6433 Interpretation in locales only permits parameter renaming through the
  6434 locale expression.  Interpretation is smart in that interpretations
  6435 that are active already do not occur in proof obligations, neither are
  6436 instantiated theorems stored in duplicate.  Use 'print_interps' to
  6437 inspect active interpretations of a particular locale.  For details,
  6438 see the Isar Reference manual.  Examples can be found in
  6439 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  6440 
  6441 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  6442 'interpret' instead.
  6443 
  6444 * New context element 'constrains' for adding type constraints to
  6445 parameters.
  6446 
  6447 * Context expressions: renaming of parameters with syntax
  6448 redeclaration.
  6449 
  6450 * Locale declaration: 'includes' disallowed.
  6451 
  6452 * Proper static binding of attribute syntax -- i.e. types / terms /
  6453 facts mentioned as arguments are always those of the locale definition
  6454 context, independently of the context of later invocations.  Moreover,
  6455 locale operations (renaming and type / term instantiation) are applied
  6456 to attribute arguments as expected.
  6457 
  6458 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  6459 actual attributes; rare situations may require Attrib.attribute to
  6460 embed those attributes into Attrib.src that lack concrete syntax.
  6461 Attribute implementations need to cooperate properly with the static
  6462 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  6463 Attrib.XXX_thm etc. already do the right thing without further
  6464 intervention.  Only unusual applications -- such as "where" or "of"
  6465 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  6466 on the context and the facts involved -- may have to assign parsed
  6467 values to argument tokens explicitly.
  6468 
  6469 * Changed parameter management in theorem generation for long goal
  6470 statements with 'includes'.  INCOMPATIBILITY: produces a different
  6471 theorem statement in rare situations.
  6472 
  6473 * Locale inspection command 'print_locale' omits notes elements.  Use
  6474 'print_locale!' to have them included in the output.
  6475 
  6476 
  6477 *** Provers ***
  6478 
  6479 * Provers/hypsubst.ML: improved version of the subst method, for
  6480 single-step rewriting: it now works in bound variable contexts. New is
  6481 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  6482 rewrite a different subterm than the original subst method, which is
  6483 still available as 'simplesubst'.
  6484 
  6485 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  6486 and quasi orders.
  6487 
  6488 * Provers/trancl.ML: new transitivity reasoner for transitive and
  6489 reflexive-transitive closure of relations.
  6490 
  6491 * Provers/blast.ML: new reference depth_limit to make blast's depth
  6492 limit (previously hard-coded with a value of 20) user-definable.
  6493 
  6494 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  6495 is peformed already.  Object-logics merely need to finish their
  6496 initial simpset configuration as before.  INCOMPATIBILITY.
  6497 
  6498 
  6499 *** HOL ***
  6500 
  6501 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  6502 
  6503   syntax (epsilon)
  6504     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  6505 
  6506 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  6507 and x-symbol; use option '-m epsilon' to get it actually printed.
  6508 Moreover, the mathematically important symbolic identifier \<epsilon>
  6509 becomes available as variable, constant etc.  INCOMPATIBILITY,
  6510 
  6511 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  6512 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  6513 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  6514 support corresponding Isar calculations.
  6515 
  6516 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  6517 instead of ":".
  6518 
  6519 * theory SetInterval: changed the syntax for open intervals:
  6520 
  6521   Old       New
  6522   {..n(}    {..<n}
  6523   {)n..}    {n<..}
  6524   {m..n(}   {m..<n}
  6525   {)m..n}   {m<..n}
  6526   {)m..n(}  {m<..<n}
  6527 
  6528 The old syntax is still supported but will disappear in the next
  6529 release.  For conversion use the following Emacs search and replace
  6530 patterns (these are not perfect but work quite well):
  6531 
  6532   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  6533   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  6534 
  6535 * Theory Commutative_Ring (in Library): method comm_ring for proving
  6536 equalities in commutative rings; method 'algebra' provides a generic
  6537 interface.
  6538 
  6539 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  6540 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  6541 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  6542 be a tuple pattern.
  6543 
  6544 Some new syntax forms are available:
  6545 
  6546   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  6547   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  6548   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  6549   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  6550 
  6551 The latter form "\<Sum>x < k. e" used to be based on a separate
  6552 function "Summation", which has been discontinued.
  6553 
  6554 * theory Finite_Set: in structured induction proofs, the insert case
  6555 is now 'case (insert x F)' instead of the old counterintuitive 'case
  6556 (insert F x)'.
  6557 
  6558 * The 'refute' command has been extended to support a much larger
  6559 fragment of HOL, including axiomatic type classes, constdefs and
  6560 typedefs, inductive datatypes and recursion.
  6561 
  6562 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  6563 Requires zChaff with proof generation to be installed.  See
  6564 HOL/ex/SAT_Examples.thy for examples.
  6565 
  6566 * Datatype induction via method 'induct' now preserves the name of the
  6567 induction variable. For example, when proving P(xs::'a list) by
  6568 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  6569 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  6570 in unstructured proof scripts.
  6571 
  6572 * Reworked implementation of records.  Improved scalability for
  6573 records with many fields, avoiding performance problems for type
  6574 inference. Records are no longer composed of nested field types, but
  6575 of nested extension types. Therefore the record type only grows linear
  6576 in the number of extensions and not in the number of fields.  The
  6577 top-level (users) view on records is preserved.  Potential
  6578 INCOMPATIBILITY only in strange cases, where the theory depends on the
  6579 old record representation. The type generated for a record is called
  6580 <record_name>_ext_type.
  6581 
  6582 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  6583 proofs triggered by a record definition or a simproc (if
  6584 quick_and_dirty is enabled).  Definitions of large records can take
  6585 quite long.
  6586 
  6587 New simproc record_upd_simproc for simplification of multiple record
  6588 updates enabled by default.  Moreover, trivial updates are also
  6589 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  6590 occasionally, since simplification is more powerful by default.
  6591 
  6592 * typedef: proper support for polymorphic sets, which contain extra
  6593 type-variables in the term.
  6594 
  6595 * Simplifier: automatically reasons about transitivity chains
  6596 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  6597 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  6598 old proofs break occasionally as simplification may now solve more
  6599 goals than previously.
  6600 
  6601 * Simplifier: converts x <= y into x = y if assumption y <= x is
  6602 present.  Works for all partial orders (class "order"), in particular
  6603 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  6604 just like y <= x.
  6605 
  6606 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  6607 bound variable or a constant then the let is unfolded.  Otherwise
  6608 first a is simplified to b, and then f b is simplified to g. If
  6609 possible we abstract b from g arriving at "let x = b in h x",
  6610 otherwise we unfold the let and arrive at g.  The simproc can be
  6611 enabled/disabled by the reference use_let_simproc.  Potential
  6612 INCOMPATIBILITY since simplification is more powerful by default.
  6613 
  6614 * Classical reasoning: the meson method now accepts theorems as arguments.
  6615 
  6616 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  6617 jobs to provide advice on the provability of subgoals.
  6618 
  6619 * Theory OrderedGroup and Ring_and_Field: various additions and
  6620 improvements to faciliate calculations involving equalities and
  6621 inequalities.
  6622 
  6623 The following theorems have been eliminated or modified
  6624 (INCOMPATIBILITY):
  6625 
  6626   abs_eq             now named abs_of_nonneg
  6627   abs_of_ge_0        now named abs_of_nonneg
  6628   abs_minus_eq       now named abs_of_nonpos
  6629   imp_abs_id         now named abs_of_nonneg
  6630   imp_abs_neg_id     now named abs_of_nonpos
  6631   mult_pos           now named mult_pos_pos
  6632   mult_pos_le        now named mult_nonneg_nonneg
  6633   mult_pos_neg_le    now named mult_nonneg_nonpos
  6634   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  6635   mult_neg           now named mult_neg_neg
  6636   mult_neg_le        now named mult_nonpos_nonpos
  6637 
  6638 * The following lemmas in Ring_and_Field have been added to the simplifier:
  6639      
  6640      zero_le_square
  6641      not_square_less_zero 
  6642 
  6643   The following lemmas have been deleted from Real/RealPow:
  6644   
  6645      realpow_zero_zero
  6646      realpow_two
  6647      realpow_less
  6648      zero_le_power
  6649      realpow_two_le
  6650      abs_realpow_two
  6651      realpow_two_abs     
  6652 
  6653 * Theory Parity: added rules for simplifying exponents.
  6654 
  6655 * Theory List:
  6656 
  6657 The following theorems have been eliminated or modified
  6658 (INCOMPATIBILITY):
  6659 
  6660   list_all_Nil       now named list_all.simps(1)
  6661   list_all_Cons      now named list_all.simps(2)
  6662   list_all_conv      now named list_all_iff
  6663   set_mem_eq         now named mem_iff
  6664 
  6665 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  6666 asymptotic "big O" calculations.  See the notes in BigO.thy.
  6667 
  6668 
  6669 *** HOL-Complex ***
  6670 
  6671 * Theory RealDef: better support for embedding natural numbers and
  6672 integers in the reals.
  6673 
  6674 The following theorems have been eliminated or modified
  6675 (INCOMPATIBILITY):
  6676 
  6677   exp_ge_add_one_self  now requires no hypotheses
  6678   real_of_int_add      reversed direction of equality (use [symmetric])
  6679   real_of_int_minus    reversed direction of equality (use [symmetric])
  6680   real_of_int_diff     reversed direction of equality (use [symmetric])
  6681   real_of_int_mult     reversed direction of equality (use [symmetric])
  6682 
  6683 * Theory RComplete: expanded support for floor and ceiling functions.
  6684 
  6685 * Theory Ln is new, with properties of the natural logarithm
  6686 
  6687 * Hyperreal: There is a new type constructor "star" for making
  6688 nonstandard types.  The old type names are now type synonyms:
  6689 
  6690   hypreal = real star
  6691   hypnat = nat star
  6692   hcomplex = complex star
  6693 
  6694 * Hyperreal: Many groups of similarly-defined constants have been
  6695 replaced by polymorphic versions (INCOMPATIBILITY):
  6696 
  6697   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  6698 
  6699   starset      <-- starsetNat, starsetC
  6700   *s*          <-- *sNat*, *sc*
  6701   starset_n    <-- starsetNat_n, starsetC_n
  6702   *sn*         <-- *sNatn*, *scn*
  6703   InternalSets <-- InternalNatSets, InternalCSets
  6704 
  6705   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  6706   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  6707   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  6708   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  6709   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  6710 
  6711 * Hyperreal: Many type-specific theorems have been removed in favor of
  6712 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  6713 
  6714   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  6715   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  6716   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  6717   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  6718   right_minus <-- hypreal_add_minus
  6719   left_minus <-- {hypreal,hcomplex}_add_minus_left
  6720   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  6721   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  6722   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  6723   mult_1_right <-- hcomplex_mult_one_right
  6724   mult_zero_left <-- hcomplex_mult_zero_left
  6725   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  6726   right_distrib <-- hypnat_add_mult_distrib2
  6727   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  6728   right_inverse <-- hypreal_mult_inverse
  6729   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  6730   order_refl <-- {hypreal,hypnat}_le_refl
  6731   order_trans <-- {hypreal,hypnat}_le_trans
  6732   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  6733   order_less_le <-- {hypreal,hypnat}_less_le
  6734   linorder_linear <-- {hypreal,hypnat}_le_linear
  6735   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  6736   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  6737   add_nonneg_nonneg <-- hypreal_le_add_order
  6738 
  6739 * Hyperreal: Separate theorems having to do with type-specific
  6740 versions of constants have been merged into theorems that apply to the
  6741 new polymorphic constants (INCOMPATIBILITY):
  6742 
  6743   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  6744   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  6745   STAR_Un <-- {STAR,NatStar,STARC}_Un
  6746   STAR_Int <-- {STAR,NatStar,STARC}_Int
  6747   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  6748   STAR_subset <-- {STAR,NatStar,STARC}_subset
  6749   STAR_mem <-- {STAR,NatStar,STARC}_mem
  6750   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  6751   STAR_diff <-- {STAR,STARC}_diff
  6752   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  6753     STARC_hcomplex_of_complex}_image_subset
  6754   starset_n_Un <-- starset{Nat,C}_n_Un
  6755   starset_n_Int <-- starset{Nat,C}_n_Int
  6756   starset_n_Compl <-- starset{Nat,C}_n_Compl
  6757   starset_n_diff <-- starset{Nat,C}_n_diff
  6758   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  6759   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  6760   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  6761   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  6762   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  6763   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  6764   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  6765   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  6766   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  6767   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  6768   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  6769   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  6770   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  6771   starfun_diff <-- starfun{C,RC,CR}_diff
  6772   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  6773   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  6774   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  6775   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  6776   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  6777   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  6778   starfun_Id <-- starfunC_Id
  6779   starfun_approx <-- starfun{Nat,CR}_approx
  6780   starfun_capprox <-- starfun{C,RC}_capprox
  6781   starfun_abs <-- starfunNat_rabs
  6782   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  6783   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  6784   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  6785   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  6786   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  6787   starfun_add_approx <-- starfunCR_add_approx
  6788   starfun_inverse_inverse <-- starfunC_inverse_inverse
  6789   starfun_divide <-- starfun{C,CR,RC}_divide
  6790   starfun_n <-- starfun{Nat,C}_n
  6791   starfun_n_mult <-- starfun{Nat,C}_n_mult
  6792   starfun_n_add <-- starfun{Nat,C}_n_add
  6793   starfun_n_add_minus <-- starfunNat_n_add_minus
  6794   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  6795   starfun_n_minus <-- starfun{Nat,C}_n_minus
  6796   starfun_n_eq <-- starfun{Nat,C}_n_eq
  6797 
  6798   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  6799   star_n_minus <-- {hypreal,hcomplex}_minus
  6800   star_n_diff <-- {hypreal,hcomplex}_diff
  6801   star_n_mult <-- {hypreal,hcomplex}_mult
  6802   star_n_inverse <-- {hypreal,hcomplex}_inverse
  6803   star_n_le <-- {hypreal,hypnat}_le
  6804   star_n_less <-- {hypreal,hypnat}_less
  6805   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  6806   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  6807   star_n_abs <-- hypreal_hrabs
  6808   star_n_divide <-- hcomplex_divide
  6809 
  6810   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  6811   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  6812   star_of_diff <-- hypreal_of_real_diff
  6813   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  6814   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  6815   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  6816   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  6817   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  6818   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  6819   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  6820   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  6821   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  6822   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  6823   star_of_number_of <-- {hypreal,hcomplex}_number_of
  6824   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  6825   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  6826   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  6827   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  6828   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  6829   star_of_power <-- hypreal_of_real_power
  6830   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  6831 
  6832 * Hyperreal: new method "transfer" that implements the transfer
  6833 principle of nonstandard analysis. With a subgoal that mentions
  6834 nonstandard types like "'a star", the command "apply transfer"
  6835 replaces it with an equivalent one that mentions only standard types.
  6836 To be successful, all free variables must have standard types; non-
  6837 standard variables must have explicit universal quantifiers.
  6838 
  6839 * Hyperreal: A theory of Taylor series.
  6840 
  6841 
  6842 *** HOLCF ***
  6843 
  6844 * Discontinued special version of 'constdefs' (which used to support
  6845 continuous functions) in favor of the general Pure one with full
  6846 type-inference.
  6847 
  6848 * New simplification procedure for solving continuity conditions; it
  6849 is much faster on terms with many nested lambda abstractions (cubic
  6850 instead of exponential time).
  6851 
  6852 * New syntax for domain package: selector names are now optional.
  6853 Parentheses should be omitted unless argument is lazy, for example:
  6854 
  6855   domain 'a stream = cons "'a" (lazy "'a stream")
  6856 
  6857 * New command 'fixrec' for defining recursive functions with pattern
  6858 matching; defining multiple functions with mutual recursion is also
  6859 supported.  Patterns may include the constants cpair, spair, up, sinl,
  6860 sinr, or any data constructor defined by the domain package. The given
  6861 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  6862 syntax and examples.
  6863 
  6864 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  6865 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  6866 but the proof obligation additionally includes an admissibility
  6867 requirement. The packages generate instances of class cpo or pcpo,
  6868 with continuity and strictness theorems for Rep and Abs.
  6869 
  6870 * HOLCF: Many theorems have been renamed according to a more standard naming
  6871 scheme (INCOMPATIBILITY):
  6872 
  6873   foo_inject:  "foo$x = foo$y ==> x = y"
  6874   foo_eq:      "(foo$x = foo$y) = (x = y)"
  6875   foo_less:    "(foo$x << foo$y) = (x << y)"
  6876   foo_strict:  "foo$UU = UU"
  6877   foo_defined: "... ==> foo$x ~= UU"
  6878   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  6879 
  6880 
  6881 *** ZF ***
  6882 
  6883 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  6884 including the First Isomorphism Theorem (on quotienting by the kernel
  6885 of a homomorphism).
  6886 
  6887 * ZF/Simplifier: install second copy of type solver that actually
  6888 makes use of TC rules declared to Isar proof contexts (or locales);
  6889 the old version is still required for ML proof scripts.
  6890 
  6891 
  6892 *** Cube ***
  6893 
  6894 * Converted to Isar theory format; use locales instead of axiomatic
  6895 theories.
  6896 
  6897 
  6898 *** ML ***
  6899 
  6900 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6901 for ||>, ||>>, |>>,
  6902 
  6903 * Pure/library.ML no longer defines its own option datatype, but uses
  6904 that of the SML basis, which has constructors NONE and SOME instead of
  6905 None and Some, as well as exception Option.Option instead of OPTION.
  6906 The functions the, if_none, is_some, is_none have been adapted
  6907 accordingly, while Option.map replaces apsome.
  6908 
  6909 * Pure/library.ML: the exception LIST has been given up in favour of
  6910 the standard exceptions Empty and Subscript, as well as
  6911 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6912 superceded by the standard hd and tl functions etc.
  6913 
  6914 A number of basic list functions are no longer exported to the ML
  6915 toplevel, as they are variants of predefined functions.  The following
  6916 suggests how one can translate existing code:
  6917 
  6918     rev_append xs ys = List.revAppend (xs, ys)
  6919     nth_elem (i, xs) = List.nth (xs, i)
  6920     last_elem xs = List.last xs
  6921     flat xss = List.concat xss
  6922     seq fs = List.app fs
  6923     partition P xs = List.partition P xs
  6924     mapfilter f xs = List.mapPartial f xs
  6925 
  6926 * Pure/library.ML: several combinators for linear functional
  6927 transformations, notably reverse application and composition:
  6928 
  6929   x |> f                f #> g
  6930   (x, y) |-> f          f #-> g
  6931 
  6932 * Pure/library.ML: introduced/changed precedence of infix operators:
  6933 
  6934   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6935   infix 2 ?;
  6936   infix 3 o oo ooo oooo;
  6937   infix 4 ~~ upto downto;
  6938 
  6939 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6940 infix operators.
  6941 
  6942 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6943 fold_map support linear functional transformations and nesting.  For
  6944 example:
  6945 
  6946   fold f [x1, ..., xN] y =
  6947     y |> f x1 |> ... |> f xN
  6948 
  6949   (fold o fold) f [xs1, ..., xsN] y =
  6950     y |> fold f xs1 |> ... |> fold f xsN
  6951 
  6952   fold f [x1, ..., xN] =
  6953     f x1 #> ... #> f xN
  6954 
  6955   (fold o fold) f [xs1, ..., xsN] =
  6956     fold f xs1 #> ... #> fold f xsN
  6957 
  6958 * Pure/library.ML: the following selectors on type 'a option are
  6959 available:
  6960 
  6961   the:               'a option -> 'a  (*partial*)
  6962   these:             'a option -> 'a  where 'a = 'b list
  6963   the_default: 'a -> 'a option -> 'a
  6964   the_list:          'a option -> 'a list
  6965 
  6966 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6967 basic operations for association lists, following natural argument
  6968 order; moreover the explicit equality predicate passed here avoids
  6969 potentially expensive polymorphic runtime equality checks.
  6970 The old functions may be expressed as follows:
  6971 
  6972   assoc = uncurry (AList.lookup (op =))
  6973   assocs = these oo AList.lookup (op =)
  6974   overwrite = uncurry (AList.update (op =)) o swap
  6975 
  6976 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6977 
  6978   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6979   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6980 
  6981 replacing make_keylist and keyfilter (occassionally used)
  6982 Naive rewrites:
  6983 
  6984   make_keylist = AList.make
  6985   keyfilter = AList.find (op =)
  6986 
  6987 * eq_fst and eq_snd now take explicit equality parameter, thus
  6988   avoiding eqtypes. Naive rewrites:
  6989 
  6990     eq_fst = eq_fst (op =)
  6991     eq_snd = eq_snd (op =)
  6992 
  6993 * Removed deprecated apl and apr (rarely used).
  6994   Naive rewrites:
  6995 
  6996     apl (n, op) =>>= curry op n
  6997     apr (op, m) =>>= fn n => op (n, m)
  6998 
  6999 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  7000 provides a reasonably efficient light-weight implementation of sets as
  7001 lists.
  7002 
  7003 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  7004 few new operations; existing lookup and update are now curried to
  7005 follow natural argument order (for use with fold etc.);
  7006 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  7007 
  7008 * Pure/General: output via the Isabelle channels of
  7009 writeln/warning/error etc. is now passed through Output.output, with a
  7010 hook for arbitrary transformations depending on the print_mode
  7011 (cf. Output.add_mode -- the first active mode that provides a output
  7012 function wins).  Already formatted output may be embedded into further
  7013 text via Output.raw; the result of Pretty.string_of/str_of and derived
  7014 functions (string_of_term/cterm/thm etc.) is already marked raw to
  7015 accommodate easy composition of diagnostic messages etc.  Programmers
  7016 rarely need to care about Output.output or Output.raw at all, with
  7017 some notable exceptions: Output.output is required when bypassing the
  7018 standard channels (writeln etc.), or in token translations to produce
  7019 properly formatted results; Output.raw is required when capturing
  7020 already output material that will eventually be presented to the user
  7021 a second time.  For the default print mode, both Output.output and
  7022 Output.raw have no effect.
  7023 
  7024 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  7025 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  7026 cumulative results are displayed at the end of a batch session.
  7027 
  7028 * Pure/General: File.sysify_path and File.quote_sysify path have been
  7029 replaced by File.platform_path and File.shell_path (with appropriate
  7030 hooks).  This provides a clean interface for unusual systems where the
  7031 internal and external process view of file names are different.
  7032 
  7033 * Pure: more efficient orders for basic syntactic entities: added
  7034 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  7035 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  7036 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  7037 orders now -- potential INCOMPATIBILITY for code that depends on a
  7038 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  7039 Library.sort_strings on result).
  7040 
  7041 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  7042 fold_types traverse types/terms from left to right, observing natural
  7043 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  7044 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  7045 
  7046 * Pure: name spaces have been refined, with significant changes of the
  7047 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  7048 to extern(_table).  The plain name entry path is superceded by a
  7049 general 'naming' context, which also includes the 'policy' to produce
  7050 a fully qualified name and external accesses of a fully qualified
  7051 name; NameSpace.extend is superceded by context dependent
  7052 Sign.declare_name.  Several theory and proof context operations modify
  7053 the naming context.  Especially note Theory.restore_naming and
  7054 ProofContext.restore_naming to get back to a sane state; note that
  7055 Theory.add_path is no longer sufficient to recover from
  7056 Theory.absolute_path in particular.
  7057 
  7058 * Pure: new flags short_names (default false) and unique_names
  7059 (default true) for controlling output of qualified names.  If
  7060 short_names is set, names are printed unqualified.  If unique_names is
  7061 reset, the name prefix is reduced to the minimum required to achieve
  7062 the original result when interning again, even if there is an overlap
  7063 with earlier declarations.
  7064 
  7065 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  7066 now 'extend', and 'merge' gets an additional Pretty.pp argument
  7067 (useful for printing error messages).  INCOMPATIBILITY.
  7068 
  7069 * Pure: major reorganization of the theory context.  Type Sign.sg and
  7070 Theory.theory are now identified, referring to the universal
  7071 Context.theory (see Pure/context.ML).  Actual signature and theory
  7072 content is managed as theory data.  The old code and interfaces were
  7073 spread over many files and structures; the new arrangement introduces
  7074 considerable INCOMPATIBILITY to gain more clarity:
  7075 
  7076   Context -- theory management operations (name, identity, inclusion,
  7077     parents, ancestors, merge, etc.), plus generic theory data;
  7078 
  7079   Sign -- logical signature and syntax operations (declaring consts,
  7080     types, etc.), plus certify/read for common entities;
  7081 
  7082   Theory -- logical theory operations (stating axioms, definitions,
  7083     oracles), plus a copy of logical signature operations (consts,
  7084     types, etc.); also a few basic management operations (Theory.copy,
  7085     Theory.merge, etc.)
  7086 
  7087 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  7088 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  7089 for convenience -- they merely return the theory.
  7090 
  7091 * Pure: type Type.tsig is superceded by theory in most interfaces.
  7092 
  7093 * Pure: the Isar proof context type is already defined early in Pure
  7094 as Context.proof (note that ProofContext.context and Proof.context are
  7095 aliases, where the latter is the preferred name).  This enables other
  7096 Isabelle components to refer to that type even before Isar is present.
  7097 
  7098 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  7099 typeK, constK, axiomK, oracleK), but provide explicit operations for
  7100 any of these kinds.  For example, Sign.intern typeK is now
  7101 Sign.intern_type, Theory.hide_space Sign.typeK is now
  7102 Theory.hide_types.  Also note that former
  7103 Theory.hide_classes/types/consts are now
  7104 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  7105 internalize their arguments!  INCOMPATIBILITY.
  7106 
  7107 * Pure: get_thm interface (of PureThy and ProofContext) expects
  7108 datatype thmref (with constructors Name and NameSelection) instead of
  7109 plain string -- INCOMPATIBILITY;
  7110 
  7111 * Pure: cases produced by proof methods specify options, where NONE
  7112 means to remove case bindings -- INCOMPATIBILITY in
  7113 (RAW_)METHOD_CASES.
  7114 
  7115 * Pure: the following operations retrieve axioms or theorems from a
  7116 theory node or theory hierarchy, respectively:
  7117 
  7118   Theory.axioms_of: theory -> (string * term) list
  7119   Theory.all_axioms_of: theory -> (string * term) list
  7120   PureThy.thms_of: theory -> (string * thm) list
  7121   PureThy.all_thms_of: theory -> (string * thm) list
  7122 
  7123 * Pure: print_tac now outputs the goal through the trace channel.
  7124 
  7125 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  7126 Reference Toplevel.debug (default false) controls detailed printing
  7127 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  7128 controls execution profiling -- set to 1 for time and 2 for space
  7129 (both increase the runtime).
  7130 
  7131 * Isar session: The initial use of ROOT.ML is now always timed,
  7132 i.e. the log will show the actual process times, in contrast to the
  7133 elapsed wall-clock time that the outer shell wrapper produces.
  7134 
  7135 * Simplifier: improved handling of bound variables (nameless
  7136 representation, avoid allocating new strings).  Simprocs that invoke
  7137 the Simplifier recursively should use Simplifier.inherit_bounds to
  7138 avoid local name clashes.  Failure to do so produces warnings
  7139 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  7140 for further details.
  7141 
  7142 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  7143 bindings for all theorems stored within a given theory; this may help
  7144 in porting non-Isar theories to Isar ones, while keeping ML proof
  7145 scripts for the time being.
  7146 
  7147 * ML operator HTML.with_charset specifies the charset begin used for
  7148 generated HTML files.  For example:
  7149 
  7150   HTML.with_charset "utf-8" use_thy "Hebrew";
  7151   HTML.with_charset "utf-8" use_thy "Chinese";
  7152 
  7153 
  7154 *** System ***
  7155 
  7156 * Allow symlinks to all proper Isabelle executables (Isabelle,
  7157 isabelle, isatool etc.).
  7158 
  7159 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  7160 isatool doc, isatool mkdir, display_drafts etc.).
  7161 
  7162 * isatool usedir: option -f allows specification of the ML file to be
  7163 used by Isabelle; default is ROOT.ML.
  7164 
  7165 * New isatool version outputs the version identifier of the Isabelle
  7166 distribution being used.
  7167 
  7168 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  7169 (containing Boolean satisfiability problems) into Isabelle/HOL
  7170 theories.
  7171 
  7172 
  7173 
  7174 New in Isabelle2004 (April 2004)
  7175 --------------------------------
  7176 
  7177 *** General ***
  7178 
  7179 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  7180   Replaces linorder.ML.
  7181 
  7182 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  7183   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  7184   (\<a>...\<z>), are now considered normal letters, and can therefore
  7185   be used anywhere where an ASCII letter (a...zA...Z) has until
  7186   now. COMPATIBILITY: This obviously changes the parsing of some
  7187   terms, especially where a symbol has been used as a binder, say
  7188   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  7189   as an identifier.  Fix it by inserting a space around former
  7190   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  7191   existing theory and ML files.
  7192 
  7193 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  7194 
  7195 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  7196   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  7197   a normal (but invisible) letter. For multiple letter subscripts repeat
  7198   \<^isub> like this: x\<^isub>1\<^isub>2.
  7199 
  7200 * Pure: There are now sub-/superscripts that can span more than one
  7201   character. Text between \<^bsub> and \<^esub> is set in subscript in
  7202   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  7203   superscript. The new control characters are not identifier parts.
  7204 
  7205 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  7206   content of "..." to the latex file instead of \isacntrl... . The "..."
  7207   may consist of any printable characters excluding the end bracket >.
  7208 
  7209 * Pure: Using new Isar command "finalconsts" (or the ML functions
  7210   Theory.add_finals or Theory.add_finals_i) it is now possible to
  7211   declare constants "final", which prevents their being given a definition
  7212   later.  It is useful for constants whose behaviour is fixed axiomatically
  7213   rather than definitionally, such as the meta-logic connectives.
  7214 
  7215 * Pure: 'instance' now handles general arities with general sorts
  7216   (i.e. intersections of classes),
  7217 
  7218 * Presentation: generated HTML now uses a CSS style sheet to make layout
  7219   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  7220   It can be changed to alter the colors/layout of generated pages.
  7221 
  7222 
  7223 *** Isar ***
  7224 
  7225 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  7226   cut_tac, subgoal_tac and thin_tac:
  7227   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  7228     locales are no longer forced to write Isar proof scripts.
  7229     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  7230     emulations.
  7231   - INCOMPATIBILITY: names of variables to be instantiated may no
  7232     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  7233     This is consistent with the instantiation attribute "where".
  7234 
  7235 * Attributes "where" and "of":
  7236   - Now take type variables of instantiated theorem into account when reading
  7237     the instantiation string.  This fixes a bug that caused instantiated
  7238     theorems to have too special types in some circumstances.
  7239   - "where" permits explicit instantiations of type variables.
  7240 
  7241 * Calculation commands "moreover" and "also" no longer interfere with
  7242   current facts ("this"), admitting arbitrary combinations with "then"
  7243   and derived forms.
  7244 
  7245 * Locales:
  7246   - Goal statements involving the context element "includes" no longer
  7247     generate theorems with internal delta predicates (those ending on
  7248     "_axioms") in the premise.
  7249     Resolve particular premise with <locale>.intro to obtain old form.
  7250   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  7251     specification and "includes" elements in goal statement.
  7252   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  7253     [intro?] and [elim?] (respectively) by default.
  7254   - Experimental command for instantiation of locales in proof contexts:
  7255         instantiate <label>[<attrs>]: <loc>
  7256     Instantiates locale <loc> and adds all its theorems to the current context
  7257     taking into account their attributes.  Label and attrs are optional
  7258     modifiers, like in theorem declarations.  If present, names of
  7259     instantiated theorems are qualified with <label>, and the attributes
  7260     <attrs> are applied after any attributes these theorems might have already.
  7261       If the locale has assumptions, a chained fact of the form
  7262     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  7263     are derived.  The command does not support old-style locales declared
  7264     with "locale (open)".
  7265       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  7266 
  7267 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  7268   (Isar) contexts.
  7269 
  7270 
  7271 *** HOL ***
  7272 
  7273 * Proof import: new image HOL4 contains the imported library from
  7274   the HOL4 system with about 2500 theorems. It is imported by
  7275   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  7276   can be used like any other Isabelle image.  See
  7277   HOL/Import/HOL/README for more information.
  7278 
  7279 * Simplifier:
  7280   - Much improved handling of linear and partial orders.
  7281     Reasoners for linear and partial orders are set up for type classes
  7282     "linorder" and "order" respectively, and are added to the default simpset
  7283     as solvers.  This means that the simplifier can build transitivity chains
  7284     to solve goals from the assumptions.
  7285   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  7286     of blast or auto after simplification become unnecessary because the goal
  7287     is solved by simplification already.
  7288 
  7289 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  7290     all proved in axiomatic type classes for semirings, rings and fields.
  7291 
  7292 * Numerics:
  7293   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  7294     now formalized using the Ring_and_Field theory mentioned above.
  7295   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  7296     than before, because now they are set up once in a generic manner.
  7297   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  7298     Look for the general versions in Ring_and_Field (and Power if they concern
  7299     exponentiation).
  7300 
  7301 * Type "rat" of the rational numbers is now available in HOL-Complex.
  7302 
  7303 * Records:
  7304   - Record types are now by default printed with their type abbreviation
  7305     instead of the list of all field types. This can be configured via
  7306     the reference "print_record_type_abbr".
  7307   - Simproc "record_upd_simproc" for simplification of multiple updates added
  7308     (not enabled by default).
  7309   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  7310     EX x. x = sel r to True (not enabled by default).
  7311   - Tactic "record_split_simp_tac" to split and simplify records added.
  7312 
  7313 * 'specification' command added, allowing for definition by
  7314   specification.  There is also an 'ax_specification' command that
  7315   introduces the new constants axiomatically.
  7316 
  7317 * arith(_tac) is now able to generate counterexamples for reals as well.
  7318 
  7319 * HOL-Algebra: new locale "ring" for non-commutative rings.
  7320 
  7321 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  7322   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  7323 
  7324 * HOL-Matrix: a first theory for matrices in HOL with an application of
  7325   matrix theory to linear programming.
  7326 
  7327 * Unions and Intersections:
  7328   The latex output syntax of UN and INT has been changed
  7329   from "\Union x \in A. B" to "\Union_{x \in A} B"
  7330   i.e. the index formulae has become a subscript.
  7331   Similarly for "\Union x. B", and for \Inter instead of \Union.
  7332 
  7333 * Unions and Intersections over Intervals:
  7334   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  7335   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  7336   like in normal math, and corresponding versions for < and for intersection.
  7337 
  7338 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  7339   lexicographic dictonary ordering has been added as "lexord".
  7340 
  7341 * ML: the legacy theory structures Int and List have been removed. They had
  7342   conflicted with ML Basis Library structures having the same names.
  7343 
  7344 * 'refute' command added to search for (finite) countermodels.  Only works
  7345   for a fragment of HOL.  The installation of an external SAT solver is
  7346   highly recommended.  See "HOL/Refute.thy" for details.
  7347 
  7348 * 'quickcheck' command: Allows to find counterexamples by evaluating
  7349   formulae under an assignment of free variables to random values.
  7350   In contrast to 'refute', it can deal with inductive datatypes,
  7351   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  7352   for examples.
  7353 
  7354 
  7355 *** HOLCF ***
  7356 
  7357 * Streams now come with concatenation and are part of the HOLCF image
  7358 
  7359 
  7360 
  7361 New in Isabelle2003 (May 2003)
  7362 ------------------------------
  7363 
  7364 *** General ***
  7365 
  7366 * Provers/simplifier:
  7367 
  7368   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  7369     Assumptions are now subject to complete mutual simplification,
  7370     not just from left to right. The simplifier now preserves
  7371     the order of assumptions.
  7372 
  7373     Potential INCOMPATIBILITY:
  7374 
  7375     -- simp sometimes diverges where the old version did
  7376        not, e.g. invoking simp on the goal
  7377 
  7378         [| P (f x); y = x; f x = f y |] ==> Q
  7379 
  7380        now gives rise to the infinite reduction sequence
  7381 
  7382         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  7383 
  7384        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  7385        kind of problem.
  7386 
  7387     -- Tactics combining classical reasoner and simplification (such as auto)
  7388        are also affected by this change, because many of them rely on
  7389        simp. They may sometimes diverge as well or yield a different numbers
  7390        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  7391        in case of problems. Sometimes subsequent calls to the classical
  7392        reasoner will fail because a preceeding call to the simplifier too
  7393        eagerly simplified the goal, e.g. deleted redundant premises.
  7394 
  7395   - The simplifier trace now shows the names of the applied rewrite rules
  7396 
  7397   - You can limit the number of recursive invocations of the simplifier
  7398     during conditional rewriting (where the simplifie tries to solve the
  7399     conditions before applying the rewrite rule):
  7400     ML "simp_depth_limit := n"
  7401     where n is an integer. Thus you can force termination where previously
  7402     the simplifier would diverge.
  7403 
  7404   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  7405 
  7406   - No longer aborts on failed congruence proof.  Instead, the
  7407     congruence is ignored.
  7408 
  7409 * Pure: New generic framework for extracting programs from constructive
  7410   proofs. See HOL/Extraction.thy for an example instantiation, as well
  7411   as HOL/Extraction for some case studies.
  7412 
  7413 * Pure: The main goal of the proof state is no longer shown by default, only
  7414 the subgoals. This behaviour is controlled by a new flag.
  7415    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  7416 (ML: Proof.show_main_goal).
  7417 
  7418 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  7419 rules whose conclusion matches subgoal 1:
  7420       PG menu: Isabelle/Isar -> Show me -> matching rules
  7421 The rules are ordered by how closely they match the subgoal.
  7422 In particular, rules that solve a subgoal outright are displayed first
  7423 (or rather last, the way they are printed).
  7424 (ML: ProofGeneral.print_intros())
  7425 
  7426 * Pure: New flag trace_unify_fail causes unification to print
  7427 diagnostic information (PG: in trace buffer) when it fails. This is
  7428 useful for figuring out why single step proofs like rule, erule or
  7429 assumption failed.
  7430 
  7431 * Pure: Locale specifications now produce predicate definitions
  7432 according to the body of text (covering assumptions modulo local
  7433 definitions); predicate "loc_axioms" covers newly introduced text,
  7434 while "loc" is cumulative wrt. all included locale expressions; the
  7435 latter view is presented only on export into the global theory
  7436 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  7437 on the old view without predicates;
  7438 
  7439 * Pure: predefined locales "var" and "struct" are useful for sharing
  7440 parameters (as in CASL, for example); just specify something like
  7441 ``var x + var y + struct M'' as import;
  7442 
  7443 * Pure: improved thms_containing: proper indexing of facts instead of
  7444 raw theorems; check validity of results wrt. current name space;
  7445 include local facts of proof configuration (also covers active
  7446 locales), cover fixed variables in index; may use "_" in term
  7447 specification; an optional limit for the number of printed facts may
  7448 be given (the default is 40);
  7449 
  7450 * Pure: disallow duplicate fact bindings within new-style theory files
  7451 (batch-mode only);
  7452 
  7453 * Provers: improved induct method: assumptions introduced by case
  7454 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  7455 the goal statement); "foo" still refers to all facts collectively;
  7456 
  7457 * Provers: the function blast.overloaded has been removed: all constants
  7458 are regarded as potentially overloaded, which improves robustness in exchange
  7459 for slight decrease in efficiency;
  7460 
  7461 * Provers/linorder: New generic prover for transitivity reasoning over
  7462 linear orders.  Note: this prover is not efficient!
  7463 
  7464 * Isar: preview of problems to finish 'show' now produce an error
  7465 rather than just a warning (in interactive mode);
  7466 
  7467 
  7468 *** HOL ***
  7469 
  7470 * arith(_tac)
  7471 
  7472  - Produces a counter example if it cannot prove a goal.
  7473    Note that the counter example may be spurious if the goal is not a formula
  7474    of quantifier-free linear arithmetic.
  7475    In ProofGeneral the counter example appears in the trace buffer.
  7476 
  7477  - Knows about div k and mod k where k is a numeral of type nat or int.
  7478 
  7479  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  7480    linear arithmetic fails. This takes account of quantifiers and divisibility.
  7481    Presburger arithmetic can also be called explicitly via presburger(_tac).
  7482 
  7483 * simp's arithmetic capabilities have been enhanced a bit: it now
  7484 takes ~= in premises into account (by performing a case split);
  7485 
  7486 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  7487 are distributed over a sum of terms;
  7488 
  7489 * New tactic "trans_tac" and method "trans" instantiate
  7490 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  7491 "<=", "<" and "=").
  7492 
  7493 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  7494 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  7495 
  7496 * 'typedef' command has new option "open" to suppress the set
  7497 definition;
  7498 
  7499 * functions Min and Max on finite sets have been introduced (theory
  7500 Finite_Set);
  7501 
  7502 * attribute [symmetric] now works for relations as well; it turns
  7503 (x,y) : R^-1 into (y,x) : R, and vice versa;
  7504 
  7505 * induct over a !!-quantified statement (say !!x1..xn):
  7506   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  7507 
  7508 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  7509 %x. None. Warning: empty_def now refers to the previously hidden definition
  7510 of the empty set.
  7511 
  7512 * Algebra: formalization of classical algebra.  Intended as base for
  7513 any algebraic development in Isabelle.  Currently covers group theory
  7514 (up to Sylow's theorem) and ring theory (Universal Property of
  7515 Univariate Polynomials).  Contributions welcome;
  7516 
  7517 * GroupTheory: deleted, since its material has been moved to Algebra;
  7518 
  7519 * Complex: new directory of the complex numbers with numeric constants,
  7520 nonstandard complex numbers, and some complex analysis, standard and
  7521 nonstandard (Jacques Fleuriot);
  7522 
  7523 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  7524 
  7525 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  7526 Fleuriot);
  7527 
  7528 * Real/HahnBanach: updated and adapted to locales;
  7529 
  7530 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  7531 Gray and Kramer);
  7532 
  7533 * UNITY: added the Meier-Sanders theory of progress sets;
  7534 
  7535 * MicroJava: bytecode verifier and lightweight bytecode verifier
  7536 as abstract algorithms, instantiated to the JVM;
  7537 
  7538 * Bali: Java source language formalization. Type system, operational
  7539 semantics, axiomatic semantics. Supported language features:
  7540 classes, interfaces, objects,virtual methods, static methods,
  7541 static/instance fields, arrays, access modifiers, definite
  7542 assignment, exceptions.
  7543 
  7544 
  7545 *** ZF ***
  7546 
  7547 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  7548 universe, etc.);
  7549 
  7550 * Main ZF: virtually all theories converted to new-style format;
  7551 
  7552 
  7553 *** ML ***
  7554 
  7555 * Pure: Tactic.prove provides sane interface for internal proofs;
  7556 omits the infamous "standard" operation, so this is more appropriate
  7557 than prove_goalw_cterm in many situations (e.g. in simprocs);
  7558 
  7559 * Pure: improved error reporting of simprocs;
  7560 
  7561 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  7562 up simprocs;
  7563 
  7564 
  7565 *** Document preparation ***
  7566 
  7567 * uses \par instead of \\ for line breaks in theory text. This may
  7568 shift some page breaks in large documents. To get the old behaviour
  7569 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  7570 
  7571 * minimized dependencies of isabelle.sty and isabellesym.sty on
  7572 other packages
  7573 
  7574 * \<euro> now needs package babel/greek instead of marvosym (which
  7575 broke \Rightarrow)
  7576 
  7577 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  7578 textcomp package)
  7579 
  7580 
  7581 
  7582 New in Isabelle2002 (March 2002)
  7583 --------------------------------
  7584 
  7585 *** Document preparation ***
  7586 
  7587 * greatly simplified document preparation setup, including more
  7588 graceful interpretation of isatool usedir -i/-d/-D options, and more
  7589 instructive isatool mkdir; users should basically be able to get
  7590 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  7591 users may run a separate document processing stage manually like this:
  7592 "isatool usedir -D output HOL Test && isatool document Test/output";
  7593 
  7594 * theory dependency graph may now be incorporated into documents;
  7595 isatool usedir -g true will produce session_graph.eps/.pdf for use
  7596 with \includegraphics of LaTeX;
  7597 
  7598 * proper spacing of consecutive markup elements, especially text
  7599 blocks after section headings;
  7600 
  7601 * support bold style (for single symbols only), input syntax is like
  7602 this: "\<^bold>\<alpha>" or "\<^bold>A";
  7603 
  7604 * \<bullet> is now output as bold \cdot by default, which looks much
  7605 better in printed text;
  7606 
  7607 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  7608 note that these symbols are currently unavailable in Proof General /
  7609 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  7610 
  7611 * isatool latex no longer depends on changed TEXINPUTS, instead
  7612 isatool document copies the Isabelle style files to the target
  7613 location;
  7614 
  7615 
  7616 *** Isar ***
  7617 
  7618 * Pure/Provers: improved proof by cases and induction;
  7619   - 'case' command admits impromptu naming of parameters (such as
  7620     "case (Suc n)");
  7621   - 'induct' method divinates rule instantiation from the inductive
  7622     claim; no longer requires excessive ?P bindings for proper
  7623     instantiation of cases;
  7624   - 'induct' method properly enumerates all possibilities of set/type
  7625     rules; as a consequence facts may be also passed through *type*
  7626     rules without further ado;
  7627   - 'induct' method now derives symbolic cases from the *rulified*
  7628     rule (before it used to rulify cases stemming from the internal
  7629     atomized version); this means that the context of a non-atomic
  7630     statement becomes is included in the hypothesis, avoiding the
  7631     slightly cumbersome show "PROP ?case" form;
  7632   - 'induct' may now use elim-style induction rules without chaining
  7633     facts, using ``missing'' premises from the goal state; this allows
  7634     rules stemming from inductive sets to be applied in unstructured
  7635     scripts, while still benefitting from proper handling of non-atomic
  7636     statements; NB: major inductive premises need to be put first, all
  7637     the rest of the goal is passed through the induction;
  7638   - 'induct' proper support for mutual induction involving non-atomic
  7639     rule statements (uses the new concept of simultaneous goals, see
  7640     below);
  7641   - append all possible rule selections, but only use the first
  7642     success (no backtracking);
  7643   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  7644   - undeclared rule case names default to numbers 1, 2, 3, ...;
  7645   - added 'print_induct_rules' (covered by help item in recent Proof
  7646     General versions);
  7647   - moved induct/cases attributes to Pure, methods to Provers;
  7648   - generic method setup instantiated for FOL and HOL;
  7649 
  7650 * Pure: support multiple simultaneous goal statements, for example
  7651 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  7652 meta-level mechanism, this acts as if several individual goals had
  7653 been stated separately; in particular common proof methods need to be
  7654 repeated in order to cover all claims; note that a single elimination
  7655 step is *not* sufficient to establish the two conjunctions, so this
  7656 fails:
  7657 
  7658   assume "A & B" then have A and B ..   (*".." fails*)
  7659 
  7660 better use "obtain" in situations as above; alternative refer to
  7661 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  7662 
  7663 * Pure: proper integration with ``locales''; unlike the original
  7664 version by Florian Kammller, Isar locales package high-level proof
  7665 contexts rather than raw logical ones (e.g. we admit to include
  7666 attributes everywhere); operations on locales include merge and
  7667 rename; support for implicit arguments (``structures''); simultaneous
  7668 type-inference over imports and text; see also HOL/ex/Locales.thy for
  7669 some examples;
  7670 
  7671 * Pure: the following commands have been ``localized'', supporting a
  7672 target locale specification "(in name)": 'lemma', 'theorem',
  7673 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  7674 stored both within the locale and at the theory level (exported and
  7675 qualified by the locale name);
  7676 
  7677 * Pure: theory goals may now be specified in ``long'' form, with
  7678 ad-hoc contexts consisting of arbitrary locale elements. for example
  7679 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  7680 definitions may be given, too); the result is a meta-level rule with
  7681 the context elements being discharged in the obvious way;
  7682 
  7683 * Pure: new proof command 'using' allows to augment currently used
  7684 facts after a goal statement ('using' is syntactically analogous to
  7685 'apply', but acts on the goal's facts only); this allows chained facts
  7686 to be separated into parts given before and after a claim, as in
  7687 ``from a and b have C using d and e <proof>'';
  7688 
  7689 * Pure: renamed "antecedent" case to "rule_context";
  7690 
  7691 * Pure: new 'judgment' command records explicit information about the
  7692 object-logic embedding (used by several tools internally); no longer
  7693 use hard-wired "Trueprop";
  7694 
  7695 * Pure: added 'corollary' command;
  7696 
  7697 * Pure: fixed 'token_translation' command;
  7698 
  7699 * Pure: removed obsolete 'exported' attribute;
  7700 
  7701 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  7702 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  7703 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  7704 
  7705 * Pure: method 'atomize' presents local goal premises as object-level
  7706 statements (atomic meta-level propositions); setup controlled via
  7707 rewrite rules declarations of 'atomize' attribute; example
  7708 application: 'induct' method with proper rule statements in improper
  7709 proof *scripts*;
  7710 
  7711 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  7712 now consider the syntactic context of assumptions, giving a better
  7713 chance to get type-inference of the arguments right (this is
  7714 especially important for locales);
  7715 
  7716 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  7717 mode;
  7718 
  7719 * Pure/obtain: the formal conclusion "thesis", being marked as
  7720 ``internal'', may no longer be reference directly in the text;
  7721 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  7722 situations;
  7723 
  7724 * Pure: generic 'sym' attribute which declares a rule both as pure
  7725 'elim?' and for the 'symmetric' operation;
  7726 
  7727 * Pure: marginal comments ``--'' may now occur just anywhere in the
  7728 text; the fixed correlation with particular command syntax has been
  7729 discontinued;
  7730 
  7731 * Pure: new method 'rules' is particularly well-suited for proof
  7732 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  7733 but often produces more compact proof terms with less detours;
  7734 
  7735 * Pure/Provers/classical: simplified integration with pure rule
  7736 attributes and methods; the classical "intro?/elim?/dest?"
  7737 declarations coincide with the pure ones; the "rule" method no longer
  7738 includes classically swapped intros; "intro" and "elim" methods no
  7739 longer pick rules from the context; also got rid of ML declarations
  7740 AddXIs/AddXEs/AddXDs; all of this has some potential for
  7741 INCOMPATIBILITY;
  7742 
  7743 * Provers/classical: attribute 'swapped' produces classical inversions
  7744 of introduction rules;
  7745 
  7746 * Provers/simplifier: 'simplified' attribute may refer to explicit
  7747 rules instead of full simplifier context; 'iff' attribute handles
  7748 conditional rules;
  7749 
  7750 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  7751 
  7752 * HOL: 'recdef' now fails on unfinished automated proofs, use
  7753 "(permissive)" option to recover old behavior;
  7754 
  7755 * HOL: 'inductive' no longer features separate (collective) attributes
  7756 for 'intros' (was found too confusing);
  7757 
  7758 * HOL: properly declared induction rules less_induct and
  7759 wf_induct_rule;
  7760 
  7761 
  7762 *** HOL ***
  7763 
  7764 * HOL: moved over to sane numeral syntax; the new policy is as
  7765 follows:
  7766 
  7767   - 0 and 1 are polymorphic constants, which are defined on any
  7768   numeric type (nat, int, real etc.);
  7769 
  7770   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  7771   binary representation internally;
  7772 
  7773   - type nat has special constructor Suc, and generally prefers Suc 0
  7774   over 1::nat and Suc (Suc 0) over 2::nat;
  7775 
  7776 This change may cause significant problems of INCOMPATIBILITY; here
  7777 are some hints on converting existing sources:
  7778 
  7779   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  7780   entities, so expressions involving "-" (unary or binary minus) need
  7781   to be spaced properly;
  7782 
  7783   - existing occurrences of "1" may need to be constraint "1::nat" or
  7784   even replaced by Suc 0; similar for old "2";
  7785 
  7786   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  7787 
  7788   - remove all special provisions on numerals in proofs;
  7789 
  7790 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  7791 representation (depends on bin_arith_simps in the default context);
  7792 
  7793 * HOL: symbolic syntax for x^2 (numeral 2);
  7794 
  7795 * HOL: the class of all HOL types is now called "type" rather than
  7796 "term"; INCOMPATIBILITY, need to adapt references to this type class
  7797 in axclass/classes, instance/arities, and (usually rare) occurrences
  7798 in typings (of consts etc.); internally the class is called
  7799 "HOL.type", ML programs should refer to HOLogic.typeS;
  7800 
  7801 * HOL/record package improvements:
  7802   - new derived operations "fields" to build a partial record section,
  7803     "extend" to promote a fixed record to a record scheme, and
  7804     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  7805     declared as simp by default;
  7806   - shared operations ("more", "fields", etc.) now need to be always
  7807     qualified) --- potential INCOMPATIBILITY;
  7808   - removed "make_scheme" operations (use "make" with "extend") --
  7809     INCOMPATIBILITY;
  7810   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  7811   - provides cases/induct rules for use with corresponding Isar
  7812     methods (for concrete records, record schemes, concrete more
  7813     parts, and schematic more parts -- in that order);
  7814   - internal definitions directly based on a light-weight abstract
  7815     theory of product types over typedef rather than datatype;
  7816 
  7817 * HOL: generic code generator for generating executable ML code from
  7818 specifications; specific support for HOL constructs such as inductive
  7819 datatypes and sets, as well as recursive functions; can be invoked
  7820 via 'generate_code' theory section;
  7821 
  7822 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  7823 
  7824 * HOL: consolidated and renamed several theories.  In particular:
  7825         Ord.thy has been absorbed into HOL.thy
  7826         String.thy has been absorbed into List.thy
  7827 
  7828 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  7829 (beware of argument permutation!);
  7830 
  7831 * HOL: linorder_less_split superseded by linorder_cases;
  7832 
  7833 * HOL/List: "nodups" renamed to "distinct";
  7834 
  7835 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  7836 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  7837   - Ex_def has changed, now need to use some_eq_ex
  7838 
  7839 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  7840 in this (rare) case use:
  7841 
  7842   delSWrapper "split_all_tac"
  7843   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  7844 
  7845 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  7846 MAY FAIL;
  7847 
  7848 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  7849 Isabelle's type classes, ^ on functions and relations has too general
  7850 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  7851 necessary to attach explicit type constraints;
  7852 
  7853 * HOL/Relation: the prefix name of the infix "O" has been changed from
  7854 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  7855 renamed accordingly (eg "compI" -> "rel_compI").
  7856 
  7857 * HOL: syntax translations now work properly with numerals and records
  7858 expressions;
  7859 
  7860 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  7861 of "lam" -- INCOMPATIBILITY;
  7862 
  7863 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  7864 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  7865 renamed "Product_Type.unit";
  7866 
  7867 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  7868 
  7869 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  7870 the "cases" method);
  7871 
  7872 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  7873 Florian Kammller);
  7874 
  7875 * HOL/IMP: updated and converted to new-style theory format; several
  7876 parts turned into readable document, with proper Isar proof texts and
  7877 some explanations (by Gerwin Klein);
  7878 
  7879 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  7880 
  7881 * HOL-Hyperreal is now a logic image;
  7882 
  7883 
  7884 *** HOLCF ***
  7885 
  7886 * Isar: consts/constdefs supports mixfix syntax for continuous
  7887 operations;
  7888 
  7889 * Isar: domain package adapted to new-style theory format, e.g. see
  7890 HOLCF/ex/Dnat.thy;
  7891 
  7892 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7893 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7894 lift.induct_tac, always use UU instead of Undef;
  7895 
  7896 * HOLCF/IMP: updated and converted to new-style theory;
  7897 
  7898 
  7899 *** ZF ***
  7900 
  7901 * Isar: proper integration of logic-specific tools and packages,
  7902 including theory commands '(co)inductive', '(co)datatype',
  7903 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7904 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7905 
  7906 * theory Main no longer includes AC; for the Axiom of Choice, base
  7907 your theory on Main_ZFC;
  7908 
  7909 * the integer library now covers quotients and remainders, with many
  7910 laws relating division to addition, multiplication, etc.;
  7911 
  7912 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7913 typeless version of the formalism;
  7914 
  7915 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7916 format;
  7917 
  7918 * ZF/Induct: new directory for examples of inductive definitions,
  7919 including theory Multiset for multiset orderings; converted to
  7920 new-style theory format;
  7921 
  7922 * ZF: many new theorems about lists, ordinals, etc.;
  7923 
  7924 
  7925 *** General ***
  7926 
  7927 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7928 variable proof controls level of detail: 0 = no proofs (only oracle
  7929 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7930 also ref manual for further ML interfaces;
  7931 
  7932 * Pure/axclass: removed obsolete ML interface
  7933 goal_subclass/goal_arity;
  7934 
  7935 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7936 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7937 separate tokens, so expressions involving minus need to be spaced
  7938 properly;
  7939 
  7940 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7941 rather than "infixl" or "infixr";
  7942 
  7943 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7944 sort constraint specifications in type inference; e.g. "x::_::foo"
  7945 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7946 type variable);
  7947 
  7948 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7949 control output of nested => (types); the default behavior is
  7950 "type_brackets";
  7951 
  7952 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7953 tokens into AST constants;
  7954 
  7955 * Pure/syntax: prefer later declarations of translations and print
  7956 translation functions; potential INCOMPATIBILITY: need to reverse
  7957 multiple declarations for same syntax element constant;
  7958 
  7959 * Pure/show_hyps reset by default (in accordance to existing Isar
  7960 practice);
  7961 
  7962 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7963 addSafter;
  7964 
  7965 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7966 as well;
  7967 
  7968 * system: tested support for MacOS X; should be able to get Isabelle +
  7969 Proof General to work in a plain Terminal after installing Poly/ML
  7970 (e.g. from the Isabelle distribution area) and GNU bash alone
  7971 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7972 support requires further installations, e.g. from
  7973 http://fink.sourceforge.net/);
  7974 
  7975 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7976 
  7977 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7978 of 40 MB), cf. ML_OPTIONS;
  7979 
  7980 * system: Proof General keywords specification is now part of the
  7981 Isabelle distribution (see etc/isar-keywords.el);
  7982 
  7983 * system: support for persistent Proof General sessions (refrain from
  7984 outdating all loaded theories on startup); user may create writable
  7985 logic images like this: ``isabelle -q HOL Test'';
  7986 
  7987 * system: smart selection of Isabelle process versus Isabelle
  7988 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7989 run both "isabelle" and "Isabelle" even if file names are badly
  7990 damaged (executable inspects the case of the first letter of its own
  7991 name); added separate "isabelle-process" and "isabelle-interface";
  7992 
  7993 * system: refrain from any attempt at filtering input streams; no
  7994 longer support ``8bit'' encoding of old isabelle font, instead proper
  7995 iso-latin characters may now be used; the related isatools
  7996 "symbolinput" and "nonascii" have disappeared as well;
  7997 
  7998 * system: removed old "xterm" interface (the print modes "xterm" and
  7999 "xterm_color" are still available for direct use in a suitable
  8000 terminal);
  8001 
  8002 
  8003 
  8004 New in Isabelle99-2 (February 2001)
  8005 -----------------------------------
  8006 
  8007 *** Overview of INCOMPATIBILITIES ***
  8008 
  8009 * HOL: please note that theories in the Library and elsewhere often use the
  8010 new-style (Isar) format; to refer to their theorems in an ML script you must
  8011 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  8012 
  8013 * HOL: inductive package no longer splits induction rule aggressively,
  8014 but only as far as specified by the introductions given; the old
  8015 format may be recovered via ML function complete_split_rule or attribute
  8016 'split_rule (complete)';
  8017 
  8018 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  8019 gfp_Tarski to gfp_unfold;
  8020 
  8021 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  8022 
  8023 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  8024 relation); infix "^^" has been renamed "``"; infix "``" has been
  8025 renamed "`"; "univalent" has been renamed "single_valued";
  8026 
  8027 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  8028 operation;
  8029 
  8030 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  8031 
  8032 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  8033 
  8034 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  8035 consequence, it is no longer monotonic wrt. the local goal context
  8036 (which is now passed through the inductive cases);
  8037 
  8038 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  8039 \<gg> to \<ggreater>;
  8040 
  8041 
  8042 *** Document preparation ***
  8043 
  8044 * \isabellestyle{NAME} selects version of Isabelle output (currently
  8045 available: are "it" for near math-mode best-style output, "sl" for
  8046 slanted text style, and "tt" for plain type-writer; if no
  8047 \isabellestyle command is given, output is according to slanted
  8048 type-writer);
  8049 
  8050 * support sub/super scripts (for single symbols only), input syntax is
  8051 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  8052 
  8053 * some more standard symbols; see Appendix A of the system manual for
  8054 the complete list of symbols defined in isabellesym.sty;
  8055 
  8056 * improved isabelle style files; more abstract symbol implementation
  8057 (should now use \isamath{...} and \isatext{...} in custom symbol
  8058 definitions);
  8059 
  8060 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  8061 state; Note that presentation of goal states does not conform to
  8062 actual human-readable proof documents.  Please do not include goal
  8063 states into document output unless you really know what you are doing!
  8064 
  8065 * proper indentation of antiquoted output with proportional LaTeX
  8066 fonts;
  8067 
  8068 * no_document ML operator temporarily disables LaTeX document
  8069 generation;
  8070 
  8071 * isatool unsymbolize tunes sources for plain ASCII communication;
  8072 
  8073 
  8074 *** Isar ***
  8075 
  8076 * Pure: Isar now suffers initial goal statements to contain unbound
  8077 schematic variables (this does not conform to actual readable proof
  8078 documents, due to unpredictable outcome and non-compositional proof
  8079 checking); users who know what they are doing may use schematic goals
  8080 for Prolog-style synthesis of proven results;
  8081 
  8082 * Pure: assumption method (an implicit finishing) now handles actual
  8083 rules as well;
  8084 
  8085 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  8086 initial goal, declare "that" only as Pure intro (only for single
  8087 steps); the "that" rule assumption may now be involved in implicit
  8088 finishing, thus ".." becomes a feasible for trivial obtains;
  8089 
  8090 * Pure: default proof step now includes 'intro_classes'; thus trivial
  8091 instance proofs may be performed by "..";
  8092 
  8093 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  8094 statements as well;
  8095 
  8096 * Pure: more robust selection of calculational rules;
  8097 
  8098 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  8099 rule (as well as the assumption rule);
  8100 
  8101 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  8102 lemmas, using the graph browser tool;
  8103 
  8104 * Pure: predict failure of "show" in interactive mode;
  8105 
  8106 * Pure: 'thms_containing' now takes actual terms as arguments;
  8107 
  8108 * HOL: improved method 'induct' --- now handles non-atomic goals
  8109 (potential INCOMPATIBILITY); tuned error handling;
  8110 
  8111 * HOL: cases and induct rules now provide explicit hints about the
  8112 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  8113 any remaining facts are inserted into the goal verbatim;
  8114 
  8115 * HOL: local contexts (aka cases) may now contain term bindings as
  8116 well; the 'cases' and 'induct' methods new provide a ?case binding for
  8117 the result to be shown in each case;
  8118 
  8119 * HOL: added 'recdef_tc' command;
  8120 
  8121 * isatool convert assists in eliminating legacy ML scripts;
  8122 
  8123 
  8124 *** HOL ***
  8125 
  8126 * HOL/Library: a collection of generic theories to be used together
  8127 with main HOL; the theory loader path already includes this directory
  8128 by default; the following existing theories have been moved here:
  8129 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  8130 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  8131 
  8132 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  8133 modelling and verification task performed in Isabelle/HOL +
  8134 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  8135 
  8136 * HOL/Algebra: special summation operator SUM no longer exists, it has
  8137 been replaced by setsum; infix 'assoc' now has priority 50 (like
  8138 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  8139 'domain', this makes the theory consistent with mathematical
  8140 literature;
  8141 
  8142 * HOL basics: added overloaded operations "inverse" and "divide"
  8143 (infix "/"), syntax for generic "abs" operation, generic summation
  8144 operator \<Sum>;
  8145 
  8146 * HOL/typedef: simplified package, provide more useful rules (see also
  8147 HOL/subset.thy);
  8148 
  8149 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  8150 now expressed as a proper nested rule (old-style tactic scripts may
  8151 require atomize_strip_tac to cope with non-atomic premises);
  8152 
  8153 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  8154 to "split_conv" (old name still available for compatibility);
  8155 
  8156 * HOL: improved concrete syntax for strings (e.g. allows translation
  8157 rules with string literals);
  8158 
  8159 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  8160  and Fleuriot's mechanization of analysis, including the transcendental
  8161  functions for the reals;
  8162 
  8163 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  8164 
  8165 
  8166 *** CTT ***
  8167 
  8168 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  8169 "lam" is displayed as TWO lambda-symbols
  8170 
  8171 * CTT: theory Main now available, containing everything (that is, Bool
  8172 and Arith);
  8173 
  8174 
  8175 *** General ***
  8176 
  8177 * Pure: the Simplifier has been implemented properly as a derived rule
  8178 outside of the actual kernel (at last!); the overall performance
  8179 penalty in practical applications is about 50%, while reliability of
  8180 the Isabelle inference kernel has been greatly improved;
  8181 
  8182 * print modes "brackets" and "no_brackets" control output of nested =>
  8183 (types) and ==> (props); the default behaviour is "brackets";
  8184 
  8185 * Provers: fast_tac (and friends) now handle actual object-logic rules
  8186 as assumptions as well;
  8187 
  8188 * system: support Poly/ML 4.0;
  8189 
  8190 * system: isatool install handles KDE version 1 or 2;
  8191 
  8192 
  8193 
  8194 New in Isabelle99-1 (October 2000)
  8195 ----------------------------------
  8196 
  8197 *** Overview of INCOMPATIBILITIES ***
  8198 
  8199 * HOL: simplification of natural numbers is much changed; to partly
  8200 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  8201 issue the following ML commands:
  8202 
  8203   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  8204   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  8205 
  8206 * HOL: simplification no longer dives into case-expressions; this is
  8207 controlled by "t.weak_case_cong" for each datatype t;
  8208 
  8209 * HOL: nat_less_induct renamed to less_induct;
  8210 
  8211 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  8212 fixsome to patch .thy and .ML sources automatically;
  8213 
  8214   select_equality  -> some_equality
  8215   select_eq_Ex     -> some_eq_ex
  8216   selectI2EX       -> someI2_ex
  8217   selectI2         -> someI2
  8218   selectI          -> someI
  8219   select1_equality -> some1_equality
  8220   Eps_sym_eq       -> some_sym_eq_trivial
  8221   Eps_eq           -> some_eq_trivial
  8222 
  8223 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  8224 
  8225 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  8226 instead);
  8227 
  8228 * HOL: the recursion equations generated by 'recdef' are now called
  8229 f.simps instead of f.rules;
  8230 
  8231 * HOL: qed_spec_mp now also handles bounded ALL as well;
  8232 
  8233 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  8234 sometimes be needed;
  8235 
  8236 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  8237 
  8238 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  8239 
  8240 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  8241 product is now "<*>" instead of "Times"; the lexicographic product is
  8242 now "<*lex*>" instead of "**";
  8243 
  8244 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  8245 of main HOL, but was unused); better use HOL's datatype package;
  8246 
  8247 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  8248 the old syntax may be recovered as follows:
  8249 
  8250   syntax (symbols)
  8251     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  8252       (infixl "\\<oplus>" 100)
  8253 
  8254 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  8255 
  8256 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  8257 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  8258 internally;
  8259 
  8260 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  8261 changed from A/r to A//r;
  8262 
  8263 * ZF: new treatment of arithmetic (nat & int) may break some old
  8264 proofs;
  8265 
  8266 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  8267 rulify -> rule_format, elimify -> elim_format, ...);
  8268 
  8269 * Isar/Provers: intro/elim/dest attributes changed; renamed
  8270 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  8271 should have to change intro!! to intro? only); replaced "delrule" by
  8272 "rule del";
  8273 
  8274 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  8275 
  8276 * Provers: strengthened force_tac by using new first_best_tac;
  8277 
  8278 * LaTeX document preparation: several changes of isabelle.sty (see
  8279 lib/texinputs);
  8280 
  8281 
  8282 *** Document preparation ***
  8283 
  8284 * formal comments (text blocks etc.) in new-style theories may now
  8285 contain antiquotations of thm/prop/term/typ/text to be presented
  8286 according to latex print mode; concrete syntax is like this:
  8287 @{term[show_types] "f(x) = a + x"};
  8288 
  8289 * isatool mkdir provides easy setup of Isabelle session directories,
  8290 including proper document sources;
  8291 
  8292 * generated LaTeX sources are now deleted after successful run
  8293 (isatool document -c); may retain a copy somewhere else via -D option
  8294 of isatool usedir;
  8295 
  8296 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  8297 style files, achieving self-contained LaTeX sources and simplifying
  8298 LaTeX debugging;
  8299 
  8300 * old-style theories now produce (crude) LaTeX output as well;
  8301 
  8302 * browser info session directories are now self-contained (may be put
  8303 on WWW server seperately); improved graphs of nested sessions; removed
  8304 graph for 'all sessions';
  8305 
  8306 * several improvements in isabelle style files; \isabellestyle{it}
  8307 produces fake math mode output; \isamarkupheader is now \section by
  8308 default; see lib/texinputs/isabelle.sty etc.;
  8309 
  8310 
  8311 *** Isar ***
  8312 
  8313 * Isar/Pure: local results and corresponding term bindings are now
  8314 subject to Hindley-Milner polymorphism (similar to ML); this
  8315 accommodates incremental type-inference very nicely;
  8316 
  8317 * Isar/Pure: new derived language element 'obtain' supports
  8318 generalized existence reasoning;
  8319 
  8320 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  8321 support accumulation of results, without applying any rules yet;
  8322 useful to collect intermediate results without explicit name
  8323 references, and for use with transitivity rules with more than 2
  8324 premises;
  8325 
  8326 * Isar/Pure: scalable support for case-analysis type proofs: new
  8327 'case' language element refers to local contexts symbolically, as
  8328 produced by certain proof methods; internally, case names are attached
  8329 to theorems as "tags";
  8330 
  8331 * Isar/Pure: theory command 'hide' removes declarations from
  8332 class/type/const name spaces;
  8333 
  8334 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  8335 indicate potential overloading;
  8336 
  8337 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  8338 
  8339 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  8340 "{a,b,c}" instead of {a,b,c};
  8341 
  8342 * Isar/Pure now provides its own version of intro/elim/dest
  8343 attributes; useful for building new logics, but beware of confusion
  8344 with the version in Provers/classical;
  8345 
  8346 * Isar/Pure: the local context of (non-atomic) goals is provided via
  8347 case name 'antecedent';
  8348 
  8349 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  8350 to the current context is now done automatically);
  8351 
  8352 * Isar/Pure: theory command 'method_setup' provides a simple interface
  8353 for definining proof methods in ML;
  8354 
  8355 * Isar/Provers: intro/elim/dest attributes changed; renamed
  8356 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  8357 most cases, one should have to change intro!! to intro? only);
  8358 replaced "delrule" by "rule del";
  8359 
  8360 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  8361 'symmetric' attribute (the latter supercedes [RS sym]);
  8362 
  8363 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  8364 method modifier); 'simp' method: 'only:' modifier removes loopers as
  8365 well (including splits);
  8366 
  8367 * Isar/Provers: Simplifier and Classical methods now support all kind
  8368 of modifiers used in the past, including 'cong', 'iff', etc.
  8369 
  8370 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  8371 of Simplifier and Classical reasoner);
  8372 
  8373 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  8374 now support named cases; major packages (inductive, datatype, primrec,
  8375 recdef) support case names and properly name parameters;
  8376 
  8377 * Isar/HOL: new transitivity rules for substitution in inequalities --
  8378 monotonicity conditions are extracted to be proven at end of
  8379 calculations;
  8380 
  8381 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  8382 method anyway;
  8383 
  8384 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  8385 split_if split_if_asm; datatype package provides theorems foo.splits =
  8386 foo.split foo.split_asm for each datatype;
  8387 
  8388 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  8389 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  8390 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  8391 use "(cases (simplified))" method in proper proof texts);
  8392 
  8393 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  8394 
  8395 * Isar: names of theorems etc. may be natural numbers as well;
  8396 
  8397 * Isar: 'pr' command: optional arguments for goals_limit and
  8398 ProofContext.prems_limit; no longer prints theory contexts, but only
  8399 proof states;
  8400 
  8401 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  8402 additional print modes to be specified; e.g. "pr(latex)" will print
  8403 proof state according to the Isabelle LaTeX style;
  8404 
  8405 * Isar: improved support for emulating tactic scripts, including proof
  8406 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  8407 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  8408 (for HOL datatypes);
  8409 
  8410 * Isar: simplified (more robust) goal selection of proof methods: 1st
  8411 goal, all goals, or explicit goal specifier (tactic emulation); thus
  8412 'proof method scripts' have to be in depth-first order;
  8413 
  8414 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  8415 
  8416 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  8417 should instead use individual commands for printing items
  8418 (print_commands, print_methods etc.);
  8419 
  8420 * Isar: added 'nothing' --- the empty list of theorems;
  8421 
  8422 
  8423 *** HOL ***
  8424 
  8425 * HOL/MicroJava: formalization of a fragment of Java, together with a
  8426 corresponding virtual machine and a specification of its bytecode
  8427 verifier and a lightweight bytecode verifier, including proofs of
  8428 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  8429 Cornelia Pusch (see also the homepage of project Bali at
  8430 http://isabelle.in.tum.de/Bali/);
  8431 
  8432 * HOL/Algebra: new theory of rings and univariate polynomials, by
  8433 Clemens Ballarin;
  8434 
  8435 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  8436 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  8437 Rasmussen;
  8438 
  8439 * HOL/Lattice: fundamental concepts of lattice theory and order
  8440 structures, including duals, properties of bounds versus algebraic
  8441 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  8442 Theorem for complete lattices etc.; may also serve as a demonstration
  8443 for abstract algebraic reasoning using axiomatic type classes, and
  8444 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  8445 
  8446 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  8447 von Oheimb;
  8448 
  8449 * HOL/IMPP: extension of IMP with local variables and mutually
  8450 recursive procedures, by David von Oheimb;
  8451 
  8452 * HOL/Lambda: converted into new-style theory and document;
  8453 
  8454 * HOL/ex/Multiquote: example of multiple nested quotations and
  8455 anti-quotations -- basically a generalized version of de-Bruijn
  8456 representation; very useful in avoiding lifting of operations;
  8457 
  8458 * HOL/record: added general record equality rule to simpset; fixed
  8459 select-update simplification procedure to handle extended records as
  8460 well; admit "r" as field name;
  8461 
  8462 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  8463 other numeric types and also as the identity of groups, rings, etc.;
  8464 
  8465 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  8466 Types nat and int belong to this axclass;
  8467 
  8468 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  8469    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  8470    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  8471   two terms #m*u and #n*u are replaced by #(m+n)*u
  8472     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  8473   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  8474     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  8475 
  8476 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  8477 powerful prover for predicate logic but knows nothing of clasets; see
  8478 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  8479 
  8480 * HOL: new version of "case_tac" subsumes both boolean case split and
  8481 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  8482 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  8483 
  8484 * HOL: simplification no longer dives into case-expressions: only the
  8485 selector expression is simplified, but not the remaining arms; to
  8486 enable full simplification of case-expressions for datatype t, you may
  8487 remove t.weak_case_cong from the simpset, either globally (Delcongs
  8488 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  8489 
  8490 * HOL/recdef: the recursion equations generated by 'recdef' for
  8491 function 'f' are now called f.simps instead of f.rules; if all
  8492 termination conditions are proved automatically, these simplification
  8493 rules are added to the simpset, as in primrec; rules may be named
  8494 individually as well, resulting in a separate list of theorems for
  8495 each equation;
  8496 
  8497 * HOL/While is a new theory that provides a while-combinator. It
  8498 permits the definition of tail-recursive functions without the
  8499 provision of a termination measure. The latter is necessary once the
  8500 invariant proof rule for while is applied.
  8501 
  8502 * HOL: new (overloaded) notation for the set of elements below/above
  8503 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  8504 
  8505 * HOL: theorems impI, allI, ballI bound as "strip";
  8506 
  8507 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  8508 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  8509 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  8510 
  8511 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  8512 
  8513 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  8514 main HOL, but was unused);
  8515 
  8516 * HOL: fewer consts declared as global (e.g. have to refer to
  8517 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  8518 
  8519 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  8520 in case of overlap with user translations (e.g. judgements over
  8521 tuples); (note that the underlying logical represenation is still
  8522 bogus);
  8523 
  8524 
  8525 *** ZF ***
  8526 
  8527 * ZF: simplification automatically cancels common terms in arithmetic
  8528 expressions over nat and int;
  8529 
  8530 * ZF: new treatment of nat to minimize type-checking: all operators
  8531 coerce their operands to a natural number using the function natify,
  8532 making the algebraic laws unconditional;
  8533 
  8534 * ZF: as above, for int: operators coerce their operands to an integer
  8535 using the function intify;
  8536 
  8537 * ZF: the integer library now contains many of the usual laws for the
  8538 orderings, including $<=, and monotonicity laws for $+ and $*;
  8539 
  8540 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  8541 simplification;
  8542 
  8543 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  8544 to the simplifier and classical reasoner simultaneously;
  8545 
  8546 
  8547 *** General ***
  8548 
  8549 * Provers: blast_tac now handles actual object-logic rules as
  8550 assumptions; note that auto_tac uses blast_tac internally as well;
  8551 
  8552 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  8553 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  8554 
  8555 * Provers: delrules now handles destruct rules as well (no longer need
  8556 explicit make_elim);
  8557 
  8558 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  8559   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8560 use instead the strong form,
  8561   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8562 in HOL, FOL and ZF the function cla_make_elim will create such rules
  8563 from destruct-rules;
  8564 
  8565 * Provers: Simplifier.easy_setup provides a fast path to basic
  8566 Simplifier setup for new object-logics;
  8567 
  8568 * Pure: AST translation rules no longer require constant head on LHS;
  8569 
  8570 * Pure: improved name spaces: ambiguous output is qualified; support
  8571 for hiding of names;
  8572 
  8573 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  8574 XSYMBOL_HOME; no longer need to do manual configuration in most
  8575 situations;
  8576 
  8577 * system: compression of ML heaps images may now be controlled via -c
  8578 option of isabelle and isatool usedir (currently only observed by
  8579 Poly/ML);
  8580 
  8581 * system: isatool installfonts may handle X-Symbol fonts as well (very
  8582 useful for remote X11);
  8583 
  8584 * system: provide TAGS file for Isabelle sources;
  8585 
  8586 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  8587 order;
  8588 
  8589 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  8590 timing flag supersedes proof_timing and Toplevel.trace;
  8591 
  8592 * ML: new combinators |>> and |>>> for incremental transformations
  8593 with secondary results (e.g. certain theory extensions):
  8594 
  8595 * ML: PureThy.add_defs gets additional argument to indicate potential
  8596 overloading (usually false);
  8597 
  8598 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  8599 results;
  8600 
  8601 
  8602 
  8603 New in Isabelle99 (October 1999)
  8604 --------------------------------
  8605 
  8606 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8607 
  8608 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  8609 are no longer simplified.  (This allows the simplifier to unfold recursive
  8610 functional programs.)  To restore the old behaviour, declare
  8611 
  8612     Delcongs [if_weak_cong];
  8613 
  8614 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  8615 complement;
  8616 
  8617 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  8618 
  8619 * HOL/datatype: mutual_induct_tac no longer exists --
  8620   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  8621 
  8622 * HOL/typedef: fixed type inference for representing set; type
  8623 arguments now have to occur explicitly on the rhs as type constraints;
  8624 
  8625 * ZF: The con_defs part of an inductive definition may no longer refer
  8626 to constants declared in the same theory;
  8627 
  8628 * HOL, ZF: the function mk_cases, generated by the inductive
  8629 definition package, has lost an argument.  To simplify its result, it
  8630 uses the default simpset instead of a supplied list of theorems.
  8631 
  8632 * HOL/List: the constructors of type list are now Nil and Cons;
  8633 
  8634 * Simplifier: the type of the infix ML functions
  8635         setSSolver addSSolver setSolver addSolver
  8636 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  8637 for packaging solvers. A solver is created via
  8638         mk_solver: string -> (thm list -> int -> tactic) -> solver
  8639 where the string argument is only a comment.
  8640 
  8641 
  8642 *** Proof tools ***
  8643 
  8644 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  8645 decision procedure for linear arithmetic. Currently it is used for
  8646 types `nat', `int', and `real' in HOL (see below); it can, should and
  8647 will be instantiated for other types and logics as well.
  8648 
  8649 * The simplifier now accepts rewrite rules with flexible heads, eg
  8650      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  8651   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  8652   matching.
  8653 
  8654 
  8655 *** General ***
  8656 
  8657 * New Isabelle/Isar subsystem provides an alternative to traditional
  8658 tactical theorem proving; together with the ProofGeneral/isar user
  8659 interface it offers an interactive environment for developing human
  8660 readable proof documents (Isar == Intelligible semi-automated
  8661 reasoning); for further information see isatool doc isar-ref,
  8662 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  8663 
  8664 * improved and simplified presentation of theories: better HTML markup
  8665 (including colors), graph views in several sizes; isatool usedir now
  8666 provides a proper interface for user theories (via -P option); actual
  8667 document preparation based on (PDF)LaTeX is available as well (for
  8668 new-style theories only); see isatool doc system for more information;
  8669 
  8670 * native support for Proof General, both for classic Isabelle and
  8671 Isabelle/Isar;
  8672 
  8673 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  8674 using the graph browser tool;
  8675 
  8676 * Isabelle manuals now also available as PDF;
  8677 
  8678 * theory loader rewritten from scratch (may not be fully
  8679 bug-compatible); old loadpath variable has been replaced by show_path,
  8680 add_path, del_path, reset_path functions; new operations such as
  8681 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  8682 isatool doc ref);
  8683 
  8684 * improved isatool install: option -k creates KDE application icon,
  8685 option -p DIR installs standalone binaries;
  8686 
  8687 * added ML_PLATFORM setting (useful for cross-platform installations);
  8688 more robust handling of platform specific ML images for SML/NJ;
  8689 
  8690 * the settings environment is now statically scoped, i.e. it is never
  8691 created again in sub-processes invoked from isabelle, isatool, or
  8692 Isabelle;
  8693 
  8694 * path element specification '~~' refers to '$ISABELLE_HOME';
  8695 
  8696 * in locales, the "assumes" and "defines" parts may be omitted if
  8697 empty;
  8698 
  8699 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  8700 long arrows);
  8701 
  8702 * new print_mode "HTML";
  8703 
  8704 * new flag show_tags controls display of tags of theorems (which are
  8705 basically just comments that may be attached by some tools);
  8706 
  8707 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  8708 mode and goal output format:
  8709 
  8710 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  8711 244c244
  8712 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  8713 ---
  8714 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  8715 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  8716 181c181
  8717 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  8718 ---
  8719 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  8720 
  8721 * function bind_thms stores lists of theorems (cf. bind_thm);
  8722 
  8723 * new shorthand tactics ftac, eatac, datac, fatac;
  8724 
  8725 * qed (and friends) now accept "" as result name; in that case the
  8726 theorem is not stored, but proper checks and presentation of the
  8727 result still apply;
  8728 
  8729 * theorem database now also indexes constants "Trueprop", "all",
  8730 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  8731 
  8732 
  8733 *** HOL ***
  8734 
  8735 ** HOL arithmetic **
  8736 
  8737 * There are now decision procedures for linear arithmetic over nat and
  8738 int:
  8739 
  8740 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  8741 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  8742 are treated as atomic; subformulae not involving type `nat' or `int'
  8743 are ignored; quantified subformulae are ignored unless they are
  8744 positive universal or negative existential. The tactic has to be
  8745 invoked by hand and can be a little bit slow. In particular, the
  8746 running time is exponential in the number of occurrences of `min' and
  8747 `max', and `-' on `nat'.
  8748 
  8749 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  8750 (negated) (in)equalities among the premises and the conclusion into
  8751 account (i.e. no compound formulae) and does not know about `min' and
  8752 `max', and `-' on `nat'. It is fast and is used automatically by the
  8753 simplifier.
  8754 
  8755 NB: At the moment, these decision procedures do not cope with mixed
  8756 nat/int formulae where the two parts interact, such as `m < n ==>
  8757 int(m) < int(n)'.
  8758 
  8759 * HOL/Numeral provides a generic theory of numerals (encoded
  8760 efficiently as bit strings); setup for types nat/int/real is in place;
  8761 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  8762 int, existing theories and proof scripts may require a few additional
  8763 type constraints;
  8764 
  8765 * integer division and remainder can now be performed on constant
  8766 arguments;
  8767 
  8768 * many properties of integer multiplication, division and remainder
  8769 are now available;
  8770 
  8771 * An interface to the Stanford Validity Checker (SVC) is available through the
  8772 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  8773 are proved automatically.  SVC must be installed separately, and its results
  8774 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  8775 invocation of the underlying oracle).  For SVC see
  8776   http://verify.stanford.edu/SVC
  8777 
  8778 * IsaMakefile: the HOL-Real target now builds an actual image;
  8779 
  8780 
  8781 ** HOL misc **
  8782 
  8783 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  8784 (in Isabelle/Isar) -- by Gertrud Bauer;
  8785 
  8786 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  8787 analysis for assembly languages with subtypes;
  8788 
  8789 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  8790 -- avoids syntactic ambiguities and treats state, transition, and
  8791 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  8792 changed syntax and (many) tactics;
  8793 
  8794 * HOL/inductive: Now also handles more general introduction rules such
  8795   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  8796   theorems are now maintained within the theory (maintained via the
  8797   "mono" attribute);
  8798 
  8799 * HOL/datatype: Now also handles arbitrarily branching datatypes
  8800   (using function types) such as
  8801 
  8802   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  8803 
  8804 * HOL/record: record_simproc (part of the default simpset) takes care
  8805 of selectors applied to updated records; record_split_tac is no longer
  8806 part of the default claset; update_defs may now be removed from the
  8807 simpset in many cases; COMPATIBILITY: old behavior achieved by
  8808 
  8809   claset_ref () := claset() addSWrapper record_split_wrapper;
  8810   Delsimprocs [record_simproc]
  8811 
  8812 * HOL/typedef: fixed type inference for representing set; type
  8813 arguments now have to occur explicitly on the rhs as type constraints;
  8814 
  8815 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  8816 names rather than an ML expression;
  8817 
  8818 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  8819 supplied later.  Program schemes can be defined, such as
  8820     "While B C s = (if B s then While B C (C s) else s)"
  8821 where the well-founded relation can be chosen after B and C have been given.
  8822 
  8823 * HOL/List: the constructors of type list are now Nil and Cons;
  8824 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  8825 course, ML tools referring to List.list.op # etc. have to be adapted;
  8826 
  8827 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  8828 disabled by default; run isabelle with option -m HOL to get back to
  8829 the original Gordon/HOL-style output;
  8830 
  8831 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  8832 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  8833 
  8834 * HOL basic syntax simplified (more orthogonal): all variants of
  8835 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  8836 Eps operator is provided as well: "SOME x. P[x]";
  8837 
  8838 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  8839 
  8840 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  8841 thus available for user theories;
  8842 
  8843 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  8844 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  8845 time;
  8846 
  8847 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  8848 several times and then mp;
  8849 
  8850 
  8851 *** LK ***
  8852 
  8853 * the notation <<...>> is now available as a notation for sequences of
  8854 formulas;
  8855 
  8856 * the simplifier is now installed
  8857 
  8858 * the axiom system has been generalized (thanks to Soren Heilmann)
  8859 
  8860 * the classical reasoner now has a default rule database
  8861 
  8862 
  8863 *** ZF ***
  8864 
  8865 * new primrec section allows primitive recursive functions to be given
  8866 directly (as in HOL) over datatypes and the natural numbers;
  8867 
  8868 * new tactics induct_tac and exhaust_tac for induction (or case
  8869 analysis) over datatypes and the natural numbers;
  8870 
  8871 * the datatype declaration of type T now defines the recursor T_rec;
  8872 
  8873 * simplification automatically does freeness reasoning for datatype
  8874 constructors;
  8875 
  8876 * automatic type-inference, with AddTCs command to insert new
  8877 type-checking rules;
  8878 
  8879 * datatype introduction rules are now added as Safe Introduction rules
  8880 to the claset;
  8881 
  8882 * the syntax "if P then x else y" is now available in addition to
  8883 if(P,x,y);
  8884 
  8885 
  8886 *** Internal programming interfaces ***
  8887 
  8888 * tuned simplifier trace output; new flag debug_simp;
  8889 
  8890 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8891 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8892 
  8893 * AxClass.axclass_tac lost the theory argument;
  8894 
  8895 * tuned current_goals_markers semantics: begin / end goal avoids
  8896 printing empty lines;
  8897 
  8898 * removed prs and prs_fn hook, which was broken because it did not
  8899 include \n in its semantics, forcing writeln to add one
  8900 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8901 string -> unit if you really want to output text without newline;
  8902 
  8903 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8904 plain output, interface builders may have to enable 'isabelle_font'
  8905 mode to get Isabelle font glyphs as before;
  8906 
  8907 * refined token_translation interface; INCOMPATIBILITY: output length
  8908 now of type real instead of int;
  8909 
  8910 * theory loader actions may be traced via new ThyInfo.add_hook
  8911 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8912 your own database of information attached to *whole* theories -- as
  8913 opposed to intra-theory data slots offered via TheoryDataFun;
  8914 
  8915 * proper handling of dangling sort hypotheses (at last!);
  8916 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8917 extra sort hypotheses that can be witnessed from the type signature;
  8918 the force_strip_shyps flag is gone, any remaining shyps are simply
  8919 left in the theorem (with a warning issued by strip_shyps_warning);
  8920 
  8921 
  8922 
  8923 New in Isabelle98-1 (October 1998)
  8924 ----------------------------------
  8925 
  8926 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8927 
  8928 * several changes of automated proof tools;
  8929 
  8930 * HOL: major changes to the inductive and datatype packages, including
  8931 some minor incompatibilities of theory syntax;
  8932 
  8933 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8934 called `inj_on';
  8935 
  8936 * HOL: removed duplicate thms in Arith:
  8937   less_imp_add_less  should be replaced by  trans_less_add1
  8938   le_imp_add_le      should be replaced by  trans_le_add1
  8939 
  8940 * HOL: unary minus is now overloaded (new type constraints may be
  8941 required);
  8942 
  8943 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8944 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8945 now taken as an integer constant.
  8946 
  8947 * Pure: ML function 'theory_of' renamed to 'theory';
  8948 
  8949 
  8950 *** Proof tools ***
  8951 
  8952 * Simplifier:
  8953   1. Asm_full_simp_tac is now more aggressive.
  8954      1. It will sometimes reorient premises if that increases their power to
  8955         simplify.
  8956      2. It does no longer proceed strictly from left to right but may also
  8957         rotate premises to achieve further simplification.
  8958      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8959      old Asm_full_simp_tac in that it does not rotate premises.
  8960   2. The simplifier now knows a little bit about nat-arithmetic.
  8961 
  8962 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8963 allows for selected deletion of wrappers, by introduction of names for
  8964 wrapper functionals.  This implies that addbefore, addSbefore,
  8965 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8966 and that adding two tactics with the same name overwrites the first
  8967 one (emitting a warning).
  8968   type wrapper = (int -> tactic) -> (int -> tactic)
  8969   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8970   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8971   delWrapper, delSWrapper: claset *  string            -> claset
  8972   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8973 
  8974 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8975 semantics; addbefore now affects only the unsafe part of step_tac
  8976 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8977 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8978 by Force_tac;
  8979 
  8980 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8981 compWrapper; added safe wrapper (and access functions for it);
  8982 
  8983 * HOL/split_all_tac is now much faster and fails if there is nothing
  8984 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8985 and the names of the automatically generated variables have changed.
  8986 split_all_tac has moved within claset() from unsafe wrappers to safe
  8987 wrappers, which means that !!-bound variables are split much more
  8988 aggressively, and safe_tac and clarify_tac now split such variables.
  8989 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8990 Note: the same holds for record_split_tac, which does the job of
  8991 split_all_tac for record fields.
  8992 
  8993 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8994 permanently to the default simpset using Addsplits just like
  8995 Addsimps. They can be removed via Delsplits just like
  8996 Delsimps. Lower-case versions are also available.
  8997 
  8998 * HOL/Simplifier: The rule split_if is now part of the default
  8999 simpset. This means that the simplifier will eliminate all occurrences
  9000 of if-then-else in the conclusion of a goal. To prevent this, you can
  9001 either remove split_if completely from the default simpset by
  9002 `Delsplits [split_if]' or remove it in a specific call of the
  9003 simplifier using `... delsplits [split_if]'.  You can also add/delete
  9004 other case splitting rules to/from the default simpset: every datatype
  9005 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  9006 t is the name of the datatype).
  9007 
  9008 * Classical reasoner / Simplifier combination: new force_tac (and
  9009 derivatives Force_tac, force) combines rewriting and classical
  9010 reasoning (and whatever other tools) similarly to auto_tac, but is
  9011 aimed to solve the given subgoal completely.
  9012 
  9013 
  9014 *** General ***
  9015 
  9016 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  9017 and `goalw': the theory is no longer needed as an explicit argument -
  9018 the current theory context is used; assumptions are no longer returned
  9019 at the ML-level unless one of them starts with ==> or !!; it is
  9020 recommended to convert to these new commands using isatool fixgoal
  9021 (backup your sources first!);
  9022 
  9023 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  9024 the current theory context, and 'theory' to lookup stored theories;
  9025 
  9026 * new theory section 'locale' for declaring constants, assumptions and
  9027 definitions that have local scope;
  9028 
  9029 * new theory section 'nonterminals' for purely syntactic types;
  9030 
  9031 * new theory section 'setup' for generic ML setup functions
  9032 (e.g. package initialization);
  9033 
  9034 * the distribution now includes Isabelle icons: see
  9035 lib/logo/isabelle-{small,tiny}.xpm;
  9036 
  9037 * isatool install - install binaries with absolute references to
  9038 ISABELLE_HOME/bin;
  9039 
  9040 * isatool logo -- create instances of the Isabelle logo (as EPS);
  9041 
  9042 * print mode 'emacs' reserved for Isamode;
  9043 
  9044 * support multiple print (ast) translations per constant name;
  9045 
  9046 * theorems involving oracles are now printed with a suffixed [!];
  9047 
  9048 
  9049 *** HOL ***
  9050 
  9051 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  9052 
  9053 * HOL/inductive package reorganized and improved: now supports mutual
  9054 definitions such as
  9055 
  9056   inductive EVEN ODD
  9057     intrs
  9058       null "0 : EVEN"
  9059       oddI "n : EVEN ==> Suc n : ODD"
  9060       evenI "n : ODD ==> Suc n : EVEN"
  9061 
  9062 new theorem list "elims" contains an elimination rule for each of the
  9063 recursive sets; inductive definitions now handle disjunctive premises
  9064 correctly (also ZF);
  9065 
  9066 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  9067 "mutual_induct" no longer exists - the induction rule is always
  9068 contained in "induct";
  9069 
  9070 
  9071 * HOL/datatype package re-implemented and greatly improved: now
  9072 supports mutually recursive datatypes such as
  9073 
  9074   datatype
  9075     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  9076             | SUM ('a aexp) ('a aexp)
  9077             | DIFF ('a aexp) ('a aexp)
  9078             | NUM 'a
  9079   and
  9080     'a bexp = LESS ('a aexp) ('a aexp)
  9081             | AND ('a bexp) ('a bexp)
  9082             | OR ('a bexp) ('a bexp)
  9083 
  9084 as well as indirectly recursive datatypes such as
  9085 
  9086   datatype
  9087     ('a, 'b) term = Var 'a
  9088                   | App 'b ((('a, 'b) term) list)
  9089 
  9090 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  9091 induction on mutually / indirectly recursive datatypes.
  9092 
  9093 Primrec equations are now stored in theory and can be accessed via
  9094 <function_name>.simps.
  9095 
  9096 INCOMPATIBILITIES:
  9097 
  9098   - Theories using datatypes must now have theory Datatype as an
  9099     ancestor.
  9100   - The specific <typename>.induct_tac no longer exists - use the
  9101     generic induct_tac instead.
  9102   - natE has been renamed to nat.exhaust - use exhaust_tac
  9103     instead of res_inst_tac ... natE. Note that the variable
  9104     names in nat.exhaust differ from the names in natE, this
  9105     may cause some "fragile" proofs to fail.
  9106   - The theorems split_<typename>_case and split_<typename>_case_asm
  9107     have been renamed to <typename>.split and <typename>.split_asm.
  9108   - Since default sorts of type variables are now handled correctly,
  9109     some datatype definitions may have to be annotated with explicit
  9110     sort constraints.
  9111   - Primrec definitions no longer require function name and type
  9112     of recursive argument.
  9113 
  9114 Consider using isatool fixdatatype to adapt your theories and proof
  9115 scripts to the new package (backup your sources first!).
  9116 
  9117 
  9118 * HOL/record package: considerably improved implementation; now
  9119 includes concrete syntax for record types, terms, updates; theorems
  9120 for surjective pairing and splitting !!-bound record variables; proof
  9121 support is as follows:
  9122 
  9123   1) standard conversions (selectors or updates applied to record
  9124 constructor terms) are part of the standard simpset;
  9125 
  9126   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  9127 made part of standard simpset and claset via addIffs;
  9128 
  9129   3) a tactic for record field splitting (record_split_tac) is part of
  9130 the standard claset (addSWrapper);
  9131 
  9132 To get a better idea about these rules you may retrieve them via
  9133 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  9134 the name of your record type.
  9135 
  9136 The split tactic 3) conceptually simplifies by the following rule:
  9137 
  9138   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  9139 
  9140 Thus any record variable that is bound by meta-all will automatically
  9141 blow up into some record constructor term, consequently the
  9142 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  9143 solve record problems automatically.
  9144 
  9145 
  9146 * reorganized the main HOL image: HOL/Integ and String loaded by
  9147 default; theory Main includes everything;
  9148 
  9149 * automatic simplification of integer sums and comparisons, using cancellation;
  9150 
  9151 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  9152 
  9153 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  9154 
  9155 * many new identities for unions, intersections, set difference, etc.;
  9156 
  9157 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  9158 called split_if, split_split, split_sum_case and split_nat_case (to go
  9159 with add/delsplits);
  9160 
  9161 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  9162 (?x::unit) = (); this is made part of the default simpset, which COULD
  9163 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  9164 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  9165 unit_abs_eta_conv is added in order to counter the effect of
  9166 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  9167 %u.f();
  9168 
  9169 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  9170 makes more sense);
  9171 
  9172 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  9173   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  9174   disjointness reasoning but breaking a few old proofs.
  9175 
  9176 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  9177 to 'converse' from 'inverse' (for compatibility with ZF and some
  9178 literature);
  9179 
  9180 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  9181 the well-founded relation;
  9182 
  9183 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  9184     Compl A.  The "Compl" syntax remains available as input syntax for this
  9185     release ONLY.
  9186 
  9187 * HOL/Update: new theory of function updates:
  9188     f(a:=b) == %x. if x=a then b else f x
  9189 may also be iterated as in f(a:=b,c:=d,...);
  9190 
  9191 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  9192 
  9193 * HOL/List:
  9194   - new function list_update written xs[i:=v] that updates the i-th
  9195     list position. May also be iterated as in xs[i:=a,j:=b,...].
  9196   - new function `upt' written [i..j(] which generates the list
  9197     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  9198     bound write [i..j], which is a shorthand for [i..j+1(].
  9199   - new lexicographic orderings and corresponding wellfoundedness theorems.
  9200 
  9201 * HOL/Arith:
  9202   - removed 'pred' (predecessor) function;
  9203   - generalized some theorems about n-1;
  9204   - many new laws about "div" and "mod";
  9205   - new laws about greatest common divisors (see theory ex/Primes);
  9206 
  9207 * HOL/Relation: renamed the relational operator r^-1 "converse"
  9208 instead of "inverse";
  9209 
  9210 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  9211   of the multiset ordering;
  9212 
  9213 * directory HOL/Real: a construction of the reals using Dedekind cuts
  9214   (not included by default);
  9215 
  9216 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  9217 
  9218 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  9219   programs, i.e. different program variables may have different types.
  9220 
  9221 * calling (stac rew i) now fails if "rew" has no effect on the goal
  9222   [previously, this check worked only if the rewrite rule was unconditional]
  9223   Now rew can involve either definitions or equalities (either == or =).
  9224 
  9225 
  9226 *** ZF ***
  9227 
  9228 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  9229   only the theorems proved on ZF.ML;
  9230 
  9231 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  9232   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  9233   disjointness reasoning but breaking a few old proofs.
  9234 
  9235 * ZF/Update: new theory of function updates
  9236     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  9237   may also be iterated as in f(a:=b,c:=d,...);
  9238 
  9239 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  9240 
  9241 * calling (stac rew i) now fails if "rew" has no effect on the goal
  9242   [previously, this check worked only if the rewrite rule was unconditional]
  9243   Now rew can involve either definitions or equalities (either == or =).
  9244 
  9245 * case_tac provided for compatibility with HOL
  9246     (like the old excluded_middle_tac, but with subgoals swapped)
  9247 
  9248 
  9249 *** Internal programming interfaces ***
  9250 
  9251 * Pure: several new basic modules made available for general use, see
  9252 also src/Pure/README;
  9253 
  9254 * improved the theory data mechanism to support encapsulation (data
  9255 kind name replaced by private Object.kind, acting as authorization
  9256 key); new type-safe user interface via functor TheoryDataFun; generic
  9257 print_data function becomes basically useless;
  9258 
  9259 * removed global_names compatibility flag -- all theory declarations
  9260 are qualified by default;
  9261 
  9262 * module Pure/Syntax now offers quote / antiquote translation
  9263 functions (useful for Hoare logic etc. with implicit dependencies);
  9264 see HOL/ex/Antiquote for an example use;
  9265 
  9266 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  9267 cterm -> thm;
  9268 
  9269 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  9270 subgoal;
  9271 
  9272 * Display.print_goals function moved to Locale.print_goals;
  9273 
  9274 * standard print function for goals supports current_goals_markers
  9275 variable for marking begin of proof, end of proof, start of goal; the
  9276 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  9277 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  9278 for example;
  9279 
  9280 
  9281 
  9282 New in Isabelle98 (January 1998)
  9283 --------------------------------
  9284 
  9285 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  9286 
  9287 * changed lexical syntax of terms / types: dots made part of long
  9288 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  9289 
  9290 * simpset (and claset) reference variable replaced by functions
  9291 simpset / simpset_ref;
  9292 
  9293 * no longer supports theory aliases (via merge) and non-trivial
  9294 implicit merge of thms' signatures;
  9295 
  9296 * most internal names of constants changed due to qualified names;
  9297 
  9298 * changed Pure/Sequence interface (see Pure/seq.ML);
  9299 
  9300 
  9301 *** General Changes ***
  9302 
  9303 * hierachically structured name spaces (for consts, types, axms, thms
  9304 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  9305 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  9306 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  9307 long_names for fully qualified output names; NOTE: ML programs
  9308 (special tactics, packages etc.) referring to internal names may have
  9309 to be adapted to cope with fully qualified names; in case of severe
  9310 backward campatibility problems try setting 'global_names' at compile
  9311 time to have enrything declared within a flat name space; one may also
  9312 fine tune name declarations in theories via the 'global' and 'local'
  9313 section;
  9314 
  9315 * reimplemented the implicit simpset and claset using the new anytype
  9316 data filed in signatures; references simpset:simpset ref etc. are
  9317 replaced by functions simpset:unit->simpset and
  9318 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  9319 to patch your ML files accordingly;
  9320 
  9321 * HTML output now includes theory graph data for display with Java
  9322 applet or isatool browser; data generated automatically via isatool
  9323 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  9324 
  9325 * defs may now be conditional; improved rewrite_goals_tac to handle
  9326 conditional equations;
  9327 
  9328 * defs now admits additional type arguments, using TYPE('a) syntax;
  9329 
  9330 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  9331 creates a new theory node; implicit merge of thms' signatures is
  9332 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  9333 transfer:theory->thm->thm in (rare) cases;
  9334 
  9335 * improved handling of draft signatures / theories; draft thms (and
  9336 ctyps, cterms) are automatically promoted to real ones;
  9337 
  9338 * slightly changed interfaces for oracles: admit many per theory, named
  9339 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  9340 
  9341 * print_goals: optional output of const types (set show_consts and
  9342 show_types);
  9343 
  9344 * improved output of warnings (###) and errors (***);
  9345 
  9346 * subgoal_tac displays a warning if the new subgoal has type variables;
  9347 
  9348 * removed old README and Makefiles;
  9349 
  9350 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  9351 
  9352 * removed obsolete init_pps and init_database;
  9353 
  9354 * deleted the obsolete tactical STATE, which was declared by
  9355     fun STATE tacfun st = tacfun st st;
  9356 
  9357 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  9358 (which abbreviates $HOME);
  9359 
  9360 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  9361 use isatool fixseq to adapt your ML programs (this works for fully
  9362 qualified references to the Sequence structure only!);
  9363 
  9364 * use_thy no longer requires writable current directory; it always
  9365 reloads .ML *and* .thy file, if either one is out of date;
  9366 
  9367 
  9368 *** Classical Reasoner ***
  9369 
  9370 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  9371 tactics that use classical reasoning to simplify a subgoal without
  9372 splitting it into several subgoals;
  9373 
  9374 * Safe_tac: like safe_tac but uses the default claset;
  9375 
  9376 
  9377 *** Simplifier ***
  9378 
  9379 * added simplification meta rules:
  9380     (asm_)(full_)simplify: simpset -> thm -> thm;
  9381 
  9382 * simplifier.ML no longer part of Pure -- has to be loaded by object
  9383 logics (again);
  9384 
  9385 * added prems argument to simplification procedures;
  9386 
  9387 * HOL, FOL, ZF: added infix function `addsplits':
  9388   instead of `<simpset> setloop (split_tac <thms>)'
  9389   you can simply write `<simpset> addsplits <thms>'
  9390 
  9391 
  9392 *** Syntax ***
  9393 
  9394 * TYPE('a) syntax for type reflection terms;
  9395 
  9396 * no longer handles consts with name "" -- declare as 'syntax' instead;
  9397 
  9398 * pretty printer: changed order of mixfix annotation preference (again!);
  9399 
  9400 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  9401 
  9402 
  9403 *** HOL ***
  9404 
  9405 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9406   with `addloop' of the simplifier to faciliate case splitting in premises.
  9407 
  9408 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  9409 
  9410 * HOL/Auth: new protocol proofs including some for the Internet
  9411   protocol TLS;
  9412 
  9413 * HOL/Map: new theory of `maps' a la VDM;
  9414 
  9415 * HOL/simplifier: simplification procedures nat_cancel_sums for
  9416 cancelling out common nat summands from =, <, <= (in)equalities, or
  9417 differences; simplification procedures nat_cancel_factor for
  9418 cancelling common factor from =, <, <= (in)equalities over natural
  9419 sums; nat_cancel contains both kinds of procedures, it is installed by
  9420 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  9421 
  9422 * HOL/simplifier: terms of the form
  9423   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  9424   are rewritten to
  9425   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  9426   and those of the form
  9427   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  9428   are rewritten to
  9429   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  9430 
  9431 * HOL/datatype
  9432   Each datatype `t' now comes with a theorem `split_t_case' of the form
  9433 
  9434   P(t_case f1 ... fn x) =
  9435      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  9436         ...
  9437        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  9438      )
  9439 
  9440   and a theorem `split_t_case_asm' of the form
  9441 
  9442   P(t_case f1 ... fn x) =
  9443     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  9444         ...
  9445        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  9446      )
  9447   which can be added to a simpset via `addsplits'. The existing theorems
  9448   expand_list_case and expand_option_case have been renamed to
  9449   split_list_case and split_option_case.
  9450 
  9451 * HOL/Arithmetic:
  9452   - `pred n' is automatically converted to `n-1'.
  9453     Users are strongly encouraged not to use `pred' any longer,
  9454     because it will disappear altogether at some point.
  9455   - Users are strongly encouraged to write "0 < n" rather than
  9456     "n ~= 0". Theorems and proof tools have been modified towards this
  9457     `standard'.
  9458 
  9459 * HOL/Lists:
  9460   the function "set_of_list" has been renamed "set" (and its theorems too);
  9461   the function "nth" now takes its arguments in the reverse order and
  9462   has acquired the infix notation "!" as in "xs!n".
  9463 
  9464 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  9465 
  9466 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  9467   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  9468 
  9469 * HOL/record: extensible records with schematic structural subtyping
  9470 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  9471 still lacks various theorems and concrete record syntax;
  9472 
  9473 
  9474 *** HOLCF ***
  9475 
  9476 * removed "axioms" and "generated by" sections;
  9477 
  9478 * replaced "ops" section by extended "consts" section, which is capable of
  9479   handling the continuous function space "->" directly;
  9480 
  9481 * domain package:
  9482   . proves theorems immediately and stores them in the theory,
  9483   . creates hierachical name space,
  9484   . now uses normal mixfix annotations (instead of cinfix...),
  9485   . minor changes to some names and values (for consistency),
  9486   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  9487   . separator between mutual domain defs: changed "," to "and",
  9488   . improved handling of sort constraints;  now they have to
  9489     appear on the left-hand side of the equations only;
  9490 
  9491 * fixed LAM <x,y,zs>.b syntax;
  9492 
  9493 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  9494 adm (%x. P (t x)), where P is chainfinite and t continuous;
  9495 
  9496 
  9497 *** FOL and ZF ***
  9498 
  9499 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9500   with `addloop' of the simplifier to faciliate case splitting in premises.
  9501 
  9502 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  9503 in HOL, they strip ALL and --> from proved theorems;
  9504 
  9505 
  9506 
  9507 New in Isabelle94-8 (May 1997)
  9508 ------------------------------
  9509 
  9510 *** General Changes ***
  9511 
  9512 * new utilities to build / run / maintain Isabelle etc. (in parts
  9513 still somewhat experimental); old Makefiles etc. still functional;
  9514 
  9515 * new 'Isabelle System Manual';
  9516 
  9517 * INSTALL text, together with ./configure and ./build scripts;
  9518 
  9519 * reimplemented type inference for greater efficiency, better error
  9520 messages and clean internal interface;
  9521 
  9522 * prlim command for dealing with lots of subgoals (an easier way of
  9523 setting goals_limit);
  9524 
  9525 
  9526 *** Syntax ***
  9527 
  9528 * supports alternative (named) syntax tables (parser and pretty
  9529 printer); internal interface is provided by add_modesyntax(_i);
  9530 
  9531 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  9532 be used in conjunction with the Isabelle symbol font; uses the
  9533 "symbols" syntax table;
  9534 
  9535 * added token_translation interface (may translate name tokens in
  9536 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  9537 the current print_mode); IMPORTANT: user print translation functions
  9538 are responsible for marking newly introduced bounds
  9539 (Syntax.mark_boundT);
  9540 
  9541 * token translations for modes "xterm" and "xterm_color" that display
  9542 names in bold, underline etc. or colors (which requires a color
  9543 version of xterm);
  9544 
  9545 * infixes may now be declared with names independent of their syntax;
  9546 
  9547 * added typed_print_translation (like print_translation, but may
  9548 access type of constant);
  9549 
  9550 
  9551 *** Classical Reasoner ***
  9552 
  9553 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  9554 some limitations.  Blast_tac...
  9555   + ignores addss, addbefore, addafter; this restriction is intrinsic
  9556   + ignores elimination rules that don't have the correct format
  9557         (the conclusion MUST be a formula variable)
  9558   + ignores types, which can make HOL proofs fail
  9559   + rules must not require higher-order unification, e.g. apply_type in ZF
  9560     [message "Function Var's argument not a bound variable" relates to this]
  9561   + its proof strategy is more general but can actually be slower
  9562 
  9563 * substitution with equality assumptions no longer permutes other
  9564 assumptions;
  9565 
  9566 * minor changes in semantics of addafter (now called addaltern); renamed
  9567 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  9568 (and access functions for it);
  9569 
  9570 * improved combination of classical reasoner and simplifier:
  9571   + functions for handling clasimpsets
  9572   + improvement of addss: now the simplifier is called _after_ the
  9573     safe steps.
  9574   + safe variant of addss called addSss: uses safe simplifications
  9575     _during_ the safe steps. It is more complete as it allows multiple
  9576     instantiations of unknowns (e.g. with slow_tac).
  9577 
  9578 *** Simplifier ***
  9579 
  9580 * added interface for simplification procedures (functions that
  9581 produce *proven* rewrite rules on the fly, depending on current
  9582 redex);
  9583 
  9584 * ordering on terms as parameter (used for ordered rewriting);
  9585 
  9586 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  9587 
  9588 * the solver is now split into a safe and an unsafe part.
  9589 This should be invisible for the normal user, except that the
  9590 functions setsolver and addsolver have been renamed to setSolver and
  9591 addSolver; added safe_asm_full_simp_tac;
  9592 
  9593 
  9594 *** HOL ***
  9595 
  9596 * a generic induction tactic `induct_tac' which works for all datatypes and
  9597 also for type `nat';
  9598 
  9599 * a generic case distinction tactic `exhaust_tac' which works for all
  9600 datatypes and also for type `nat';
  9601 
  9602 * each datatype comes with a function `size';
  9603 
  9604 * patterns in case expressions allow tuple patterns as arguments to
  9605 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  9606 
  9607 * primrec now also works with type nat;
  9608 
  9609 * recdef: a new declaration form, allows general recursive functions to be
  9610 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  9611 
  9612 * the constant for negation has been renamed from "not" to "Not" to
  9613 harmonize with FOL, ZF, LK, etc.;
  9614 
  9615 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  9616 infinite lists;
  9617 
  9618 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  9619 
  9620 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  9621 problems in commutative rings, using axiomatic type classes for + and *;
  9622 
  9623 * more examples in HOL/MiniML and HOL/Auth;
  9624 
  9625 * more default rewrite rules for quantifiers, union/intersection;
  9626 
  9627 * a new constant `arbitrary == @x.False';
  9628 
  9629 * HOLCF/IOA replaces old HOL/IOA;
  9630 
  9631 * HOLCF changes: derived all rules and arities
  9632   + axiomatic type classes instead of classes
  9633   + typedef instead of faking type definitions
  9634   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  9635   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  9636   + eliminated the types void, one, tr
  9637   + use unit lift and bool lift (with translations) instead of one and tr
  9638   + eliminated blift from Lift3.thy (use Def instead of blift)
  9639   all eliminated rules are derived as theorems --> no visible changes ;
  9640 
  9641 
  9642 *** ZF ***
  9643 
  9644 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  9645 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  9646 as ZF_cs addSIs [equalityI];
  9647 
  9648 
  9649 
  9650 New in Isabelle94-7 (November 96)
  9651 ---------------------------------
  9652 
  9653 * allowing negative levels (as offsets) in prlev and choplev;
  9654 
  9655 * super-linear speedup for large simplifications;
  9656 
  9657 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  9658 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  9659 FAIL); can suppress it using the command Delsimps (ex_simps @
  9660 all_simps); De Morgan laws are also now included, by default;
  9661 
  9662 * improved printing of ==>  :  ~:
  9663 
  9664 * new object-logic "Sequents" adds linear logic, while replacing LK
  9665 and Modal (thanks to Sara Kalvala);
  9666 
  9667 * HOL/Auth: correctness proofs for authentication protocols;
  9668 
  9669 * HOL: new auto_tac combines rewriting and classical reasoning (many
  9670 examples on HOL/Auth);
  9671 
  9672 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  9673 the rewriter and classical reasoner simultaneously;
  9674 
  9675 * function uresult no longer returns theorems in "standard" format;
  9676 regain previous version by: val uresult = standard o uresult;
  9677 
  9678 
  9679 
  9680 New in Isabelle94-6
  9681 -------------------
  9682 
  9683 * oracles -- these establish an interface between Isabelle and trusted
  9684 external reasoners, which may deliver results as theorems;
  9685 
  9686 * proof objects (in particular record all uses of oracles);
  9687 
  9688 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  9689 
  9690 * "constdefs" section in theory files;
  9691 
  9692 * "primrec" section (HOL) no longer requires names;
  9693 
  9694 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  9695 
  9696 
  9697 
  9698 New in Isabelle94-5
  9699 -------------------
  9700 
  9701 * reduced space requirements;
  9702 
  9703 * automatic HTML generation from theories;
  9704 
  9705 * theory files no longer require "..." (quotes) around most types;
  9706 
  9707 * new examples, including two proofs of the Church-Rosser theorem;
  9708 
  9709 * non-curried (1994) version of HOL is no longer distributed;
  9710 
  9711 
  9712 
  9713 New in Isabelle94-4
  9714 -------------------
  9715 
  9716 * greatly reduced space requirements;
  9717 
  9718 * theory files (.thy) no longer require \...\ escapes at line breaks;
  9719 
  9720 * searchable theorem database (see the section "Retrieving theorems" on
  9721 page 8 of the Reference Manual);
  9722 
  9723 * new examples, including Grabczewski's monumental case study of the
  9724 Axiom of Choice;
  9725 
  9726 * The previous version of HOL renamed to Old_HOL;
  9727 
  9728 * The new version of HOL (previously called CHOL) uses a curried syntax
  9729 for functions.  Application looks like f a b instead of f(a,b);
  9730 
  9731 * Mutually recursive inductive definitions finally work in HOL;
  9732 
  9733 * In ZF, pattern-matching on tuples is now available in all abstractions and
  9734 translates to the operator "split";
  9735 
  9736 
  9737 
  9738 New in Isabelle94-3
  9739 -------------------
  9740 
  9741 * new infix operator, addss, allowing the classical reasoner to
  9742 perform simplification at each step of its search.  Example:
  9743         fast_tac (cs addss ss)
  9744 
  9745 * a new logic, CHOL, the same as HOL, but with a curried syntax
  9746 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  9747 look like (a,b) instead of <a,b>;
  9748 
  9749 * PLEASE NOTE: CHOL will eventually replace HOL!
  9750 
  9751 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  9752 It translates to the operator "split".  A new theory of integers is available;
  9753 
  9754 * In ZF, integer numerals now denote two's-complement binary integers.
  9755 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  9756 
  9757 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  9758 of the Axiom of Choice;
  9759 
  9760 
  9761 
  9762 New in Isabelle94-2
  9763 -------------------
  9764 
  9765 * Significantly faster resolution;
  9766 
  9767 * the different sections in a .thy file can now be mixed and repeated
  9768 freely;
  9769 
  9770 * Database of theorems for FOL, HOL and ZF.  New
  9771 commands including qed, qed_goal and bind_thm store theorems in the database.
  9772 
  9773 * Simple database queries: return a named theorem (get_thm) or all theorems of
  9774 a given theory (thms_of), or find out what theory a theorem was proved in
  9775 (theory_of_thm);
  9776 
  9777 * Bugs fixed in the inductive definition and datatype packages;
  9778 
  9779 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  9780 and HOL_dup_cs obsolete;
  9781 
  9782 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  9783 have been removed;
  9784 
  9785 * Simpler definition of function space in ZF;
  9786 
  9787 * new results about cardinal and ordinal arithmetic in ZF;
  9788 
  9789 * 'subtype' facility in HOL for introducing new types as subsets of existing
  9790 types;
  9791 
  9792 :mode=text:wrap=hard:maxLineLen=72: