NEWS
author haftmann
Fri, 06 Apr 2012 18:17:16 +0200
changeset 48259 d654c73e4b12
parent 48207 803729c9fd4d
child 48261 b72fa7bf9a10
permissions -rw-r--r--
no preference wrt. fold(l/r); prefer fold rather than foldr for iterating over lists in generated code
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Prover IDE (PIDE) improvements:
    10 
    11   - markup for bound variables
    12   - markup for types of term variables (e.g. displayed as tooltips)
    13   - support for user-defined Isar commands within the running session
    14   - improved support for Unicode outside original 16bit range
    15     e.g. glyph for \<A> (thanks to jEdit 4.5.1)
    16 
    17 * Updated and extended reference manuals ("isar-ref" and
    18 "implementation"); reduced remaining material in old "ref" manual.
    19 
    20 * Rule attributes in local theory declarations (e.g. locale or class)
    21 are now statically evaluated: the resulting theorem is stored instead
    22 of the original expression.  INCOMPATIBILITY in rare situations, where
    23 the historic accident of dynamic re-evaluation in interpretations
    24 etc. was exploited.
    25 
    26 * Commands 'lemmas' and 'theorems' allow local variables using 'for'
    27 declaration, and results are standardized before being stored.  Thus
    28 old-style "standard" after instantiation or composition of facts
    29 becomes obsolete.  Minor INCOMPATIBILITY, due to potential change of
    30 indices of schematic variables.
    31 
    32 * Renamed some inner syntax categories:
    33 
    34     num ~> num_token
    35     xnum ~> xnum_token
    36     xstr ~> str_token
    37 
    38 Minor INCOMPATIBILITY.  Note that in practice "num_const" or
    39 "num_position" etc. are mainly used instead (which also include
    40 position information via constraints).
    41 
    42 * Simplified configuration options for syntax ambiguity: see
    43 "syntax_ambiguity_warning" and "syntax_ambiguity_limit" in isar-ref
    44 manual.  Minor INCOMPATIBILITY.
    45 
    46 * Forward declaration of outer syntax keywords within the theory
    47 header -- minor INCOMPATIBILITY for user-defined commands.  Allow new
    48 commands to be used in the same theory where defined.
    49 
    50 * ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
    51 (not just JRE).
    52 
    53 
    54 *** Pure ***
    55 
    56 * Command 'definition' no longer exports the foundational "raw_def"
    57 into the user context.  Minor INCOMPATIBILITY, may use the regular
    58 "def" result with attribute "abs_def" to imitate the old version.
    59 
    60 * Attribute "abs_def" turns an equation of the form "f x y == t" into
    61 "f == %x y. t", which ensures that "simp" or "unfold" steps always
    62 expand it.  This also works for object-logic equality.  (Formerly
    63 undocumented feature.)
    64 
    65 * Discontinued old "prems" fact, which used to refer to the accidental
    66 collection of foundational premises in the context (marked as legacy
    67 since Isabelle2011).
    68 
    69 * Obsolete command 'types' has been discontinued.  Use 'type_synonym'
    70 instead.  INCOMPATIBILITY.
    71 
    72 * Ancient code generator for SML and its commands 'code_module',
    73 'code_library', 'consts_code', 'types_code' have been discontinued.
    74 Use commands of the generic code generator instead.  INCOMPATIBILITY.
    75 
    76 * Redundant attribute 'code_inline' has been discontinued. Use
    77 'code_unfold' instead.  INCOMPATIBILITY.
    78 
    79 * Dropped attribute 'code_unfold_post' in favor of the its dual
    80 'code_abbrev', which yields a common pattern in definitions like
    81 
    82   definition [code_abbrev]: "f = t"
    83 
    84 INCOMPATIBILITY.
    85 
    86 * Sort constraints are now propagated in simultaneous statements, just
    87 like type constraints.  INCOMPATIBILITY in rare situations, where
    88 distinct sorts used to be assigned accidentally.  For example:
    89 
    90   lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"
    91 
    92   lemma "P (x::'a)" and "Q (y::'a::bar)"
    93     -- "now uniform 'a::bar instead of default sort for first occurence (!)"
    94 
    95 
    96 *** HOL ***
    97 
    98 * New tutorial Programming and Proving in Isabelle/HOL
    99 
   100 * The representation of numerals has changed. We now have a datatype
   101 "num" representing strictly positive binary numerals, along with
   102 functions "numeral :: num => 'a" and "neg_numeral :: num => 'a" to
   103 represent positive and negated numeric literals, respectively. (See
   104 definitions in Num.thy.) Potential INCOMPATIBILITY; some user theories
   105 may require adaptations:
   106 
   107   - Theorems with number_ring or number_semiring constraints: These
   108     classes are gone; use comm_ring_1 or comm_semiring_1 instead.
   109 
   110   - Theories defining numeric types: Remove number, number_semiring,
   111     and number_ring instances. Defer all theorems about numerals until
   112     after classes one and semigroup_add have been instantiated.
   113 
   114   - Numeral-only simp rules: Replace each rule having a "number_of v"
   115     pattern with two copies, one for numeral and one for neg_numeral.
   116 
   117   - Theorems about subclasses of semiring_1 or ring_1: These classes
   118     automatically support numerals now, so more simp rules and
   119     simprocs may now apply within the proof.
   120 
   121   - Definitions and theorems using old constructors Pls/Min/Bit0/Bit1:
   122     Redefine using other integer operations.
   123 
   124 * Type 'a set is now a proper type constructor (just as before
   125 Isabelle2008).  Definitions mem_def and Collect_def have disappeared.
   126 Non-trivial INCOMPATIBILITY.  For developments keeping predicates and
   127 sets separate, it is often sufficient to rephrase sets S accidentally
   128 used as predicates by "%x. x : S" and predicates P accidentally used
   129 as sets by "{x. P x}".  Corresponding proofs in a first step should be
   130 pruned from any tinkering with former theorems mem_def and
   131 Collect_def as far as possible.
   132 For developments which deliberately mixed predicates and
   133 sets, a planning step is necessary to determine what should become a
   134 predicate and what a set.  It can be helpful to carry out that step in
   135 Isabelle2011-1 before jumping right into the current release.
   136 
   137 * Code generation by default implements sets as container type rather
   138 than predicates.  INCOMPATIBILITY.
   139 
   140 * New proof import from HOL Light: Faster, simpler, and more scalable.
   141 Requires a proof bundle, which is available as an external component.
   142 Removed old (and mostly dead) Importer for HOL4 and HOL Light.
   143 INCOMPATIBILITY.
   144 
   145 * New type synonym 'a rel = ('a * 'a) set
   146 
   147 * Theory Divides: Discontinued redundant theorems about div and mod.
   148 INCOMPATIBILITY, use the corresponding generic theorems instead.
   149 
   150   DIVISION_BY_ZERO ~> div_by_0, mod_by_0
   151   zdiv_self ~> div_self
   152   zmod_self ~> mod_self
   153   zdiv_zero ~> div_0
   154   zmod_zero ~> mod_0
   155   zdiv_zmod_equality ~> div_mod_equality2
   156   zdiv_zmod_equality2 ~> div_mod_equality
   157   zmod_zdiv_trivial ~> mod_div_trivial
   158   zdiv_zminus_zminus ~> div_minus_minus
   159   zmod_zminus_zminus ~> mod_minus_minus
   160   zdiv_zminus2 ~> div_minus_right
   161   zmod_zminus2 ~> mod_minus_right
   162   zdiv_minus1_right ~> div_minus1_right
   163   zmod_minus1_right ~> mod_minus1_right
   164   zdvd_mult_div_cancel ~> dvd_mult_div_cancel
   165   zmod_zmult1_eq ~> mod_mult_right_eq
   166   zpower_zmod ~> power_mod
   167   zdvd_zmod ~> dvd_mod
   168   zdvd_zmod_imp_zdvd ~> dvd_mod_imp_dvd
   169   mod_mult_distrib ~> mult_mod_left
   170   mod_mult_distrib2 ~> mult_mod_right
   171 
   172 * Removed redundant theorems nat_mult_2 and nat_mult_2_right; use
   173 generic mult_2 and mult_2_right instead. INCOMPATIBILITY.
   174 
   175 * More default pred/set conversions on a couple of relation operations
   176 and predicates.  Added powers of predicate relations.
   177 Consolidation of some relation theorems:
   178 
   179   converse_def ~> converse_unfold
   180   rel_comp_def ~> rel_comp_unfold
   181   symp_def ~> (dropped, use symp_def and sym_def instead)
   182   transp_def ~> transp_trans
   183   Domain_def ~> Domain_unfold
   184   Range_def ~> Domain_converse [symmetric]
   185 
   186 Generalized theorems INF_INT_eq, INF_INT_eq2, SUP_UN_eq, SUP_UN_eq2.
   187 
   188 See theory "Relation" for examples for making use of pred/set conversions
   189 by means of attributes "to_set" and "to_pred".
   190 
   191 INCOMPATIBILITY.
   192 
   193 * Consolidated various theorem names relating to Finite_Set.fold
   194 combinator:
   195 
   196   inf_INFI_fold_inf ~> inf_INF_fold_inf
   197   sup_SUPR_fold_sup ~> sup_SUP_fold_sup
   198   INFI_fold_inf ~> INF_fold_inf
   199   SUPR_fold_sup ~> SUP_fold_sup
   200   union_set ~> union_set_fold
   201   minus_set ~> minus_set_fold
   202 
   203 INCOMPATIBILITY.
   204 
   205 * Consolidated theorem names concerning fold combinators:
   206 
   207   INFI_set_fold ~> INF_set_fold
   208   SUPR_set_fold ~> SUP_set_fold
   209   INF_code ~> INF_set_foldr
   210   SUP_code ~> SUP_set_foldr
   211   foldr.simps ~> foldr.simps (in point-free formulation)
   212   foldr_fold_rev ~> foldr_conv_fold
   213   foldl_fold ~> foldl_conv_fold
   214   foldr_foldr ~> foldr_conv_foldl
   215   foldl_foldr ~> foldl_conv_foldr
   216 
   217 INCOMPATIBILITY.
   218 
   219 * Dropped rarely useful theorems concerning fold combinators:
   220 foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
   221 rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
   222 concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
   223 foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
   224 listsum_conv_fold, listsum_foldl, sort_foldl_insort, foldl_assoc,
   225 foldr_conv_foldl, start_le_sum, elem_le_sum, sum_eq_0_conv.
   226 INCOMPATIBILITY.  For the common phrases "%xs. List.foldr plus xs 0"
   227 and "List.foldl plus 0", prefer "List.listsum".  Otherwise it can
   228 be useful to boil down "List.foldr" and "List.foldl" to "List.fold"
   229 by unfolding "foldr_conv_fold" and "foldl_conv_fold".  
   230 
   231 * Congruence rules Option.map_cong and Option.bind_cong for recursion
   232 through option types.
   233 
   234 * Concrete syntax for case expressions includes constraints for source
   235 positions, and thus produces Prover IDE markup for its bindings.
   236 INCOMPATIBILITY for old-style syntax translations that augment the
   237 pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of
   238 one_case.
   239 
   240 * Discontinued configuration option "syntax_positions": atomic terms
   241 in parse trees are always annotated by position constraints.
   242 
   243 * Finite_Set.fold now qualified.  INCOMPATIBILITY.
   244 
   245 * Renamed some facts on canonical fold on lists, in order to avoid
   246 problems with interpretation involving corresponding facts on foldl
   247 with the same base names:
   248 
   249   fold_set_remdups ~> fold_set_fold_remdups
   250   fold_set ~> fold_set_fold
   251   fold1_set ~> fold1_set_fold
   252 
   253 INCOMPATIBILITY.
   254 
   255 * Renamed facts about the power operation on relations, i.e., relpow
   256   to match the constant's name:
   257   
   258   rel_pow_1 ~> relpow_1
   259   rel_pow_0_I ~> relpow_0_I
   260   rel_pow_Suc_I ~> relpow_Suc_I
   261   rel_pow_Suc_I2 ~> relpow_Suc_I2
   262   rel_pow_0_E ~> relpow_0_E
   263   rel_pow_Suc_E ~> relpow_Suc_E
   264   rel_pow_E ~> relpow_E
   265   rel_pow_Suc_D2 ~> relpow_Suc_D2
   266   rel_pow_Suc_E2 ~> relpow_Suc_E2 
   267   rel_pow_Suc_D2' ~> relpow_Suc_D2'
   268   rel_pow_E2 ~> relpow_E2
   269   rel_pow_add ~> relpow_add
   270   rel_pow_commute ~> relpow
   271   rel_pow_empty ~> relpow_empty:
   272   rtrancl_imp_UN_rel_pow ~> rtrancl_imp_UN_relpow
   273   rel_pow_imp_rtrancl ~> relpow_imp_rtrancl
   274   rtrancl_is_UN_rel_pow ~> rtrancl_is_UN_relpow
   275   rtrancl_imp_rel_pow ~> rtrancl_imp_relpow
   276   rel_pow_fun_conv ~> relpow_fun_conv
   277   rel_pow_finite_bounded1 ~> relpow_finite_bounded1
   278   rel_pow_finite_bounded ~> relpow_finite_bounded
   279   rtrancl_finite_eq_rel_pow ~> rtrancl_finite_eq_relpow
   280   trancl_finite_eq_rel_pow ~> trancl_finite_eq_relpow
   281   single_valued_rel_pow ~> single_valued_relpow
   282  
   283 INCOMPATIBILITY.
   284 
   285 * New theory HOL/Library/DAList provides an abstract type for association
   286   lists with distinct keys.
   287 
   288 * 'datatype' specifications allow explicit sort constraints.
   289 
   290 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
   291 use theory HOL/Library/Nat_Bijection instead.
   292 
   293 * Session HOL-Word: Discontinued many redundant theorems specific to
   294 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
   295 instead.
   296 
   297   word_sub_alt ~> word_sub_wi
   298   word_add_alt ~> word_add_def
   299   word_mult_alt ~> word_mult_def
   300   word_minus_alt ~> word_minus_def
   301   word_0_alt ~> word_0_wi
   302   word_1_alt ~> word_1_wi
   303   word_add_0 ~> add_0_left
   304   word_add_0_right ~> add_0_right
   305   word_mult_1 ~> mult_1_left
   306   word_mult_1_right ~> mult_1_right
   307   word_add_commute ~> add_commute
   308   word_add_assoc ~> add_assoc
   309   word_add_left_commute ~> add_left_commute
   310   word_mult_commute ~> mult_commute
   311   word_mult_assoc ~> mult_assoc
   312   word_mult_left_commute ~> mult_left_commute
   313   word_left_distrib ~> left_distrib
   314   word_right_distrib ~> right_distrib
   315   word_left_minus ~> left_minus
   316   word_diff_0_right ~> diff_0_right
   317   word_diff_self ~> diff_self
   318   word_sub_def ~> diff_minus
   319   word_diff_minus ~> diff_minus
   320   word_add_ac ~> add_ac
   321   word_mult_ac ~> mult_ac
   322   word_plus_ac0 ~> add_0_left add_0_right add_ac
   323   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
   324   word_order_trans ~> order_trans
   325   word_order_refl ~> order_refl
   326   word_order_antisym ~> order_antisym
   327   word_order_linear ~> linorder_linear
   328   lenw1_zero_neq_one ~> zero_neq_one
   329   word_number_of_eq ~> number_of_eq
   330   word_of_int_add_hom ~> wi_hom_add
   331   word_of_int_sub_hom ~> wi_hom_sub
   332   word_of_int_mult_hom ~> wi_hom_mult
   333   word_of_int_minus_hom ~> wi_hom_neg
   334   word_of_int_succ_hom ~> wi_hom_succ
   335   word_of_int_pred_hom ~> wi_hom_pred
   336   word_of_int_0_hom ~> word_0_wi
   337   word_of_int_1_hom ~> word_1_wi
   338 
   339 * Clarified attribute "mono_set": pure declaration without modifying
   340 the result of the fact expression.
   341 
   342 * "Transitive_Closure.ntrancl": bounded transitive closure on
   343 relations.
   344 
   345 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
   346 
   347 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
   348 
   349 * Theory Int: Discontinued many legacy theorems specific to type int.
   350 INCOMPATIBILITY, use the corresponding generic theorems instead.
   351 
   352   zminus_zminus ~> minus_minus
   353   zminus_0 ~> minus_zero
   354   zminus_zadd_distrib ~> minus_add_distrib
   355   zadd_commute ~> add_commute
   356   zadd_assoc ~> add_assoc
   357   zadd_left_commute ~> add_left_commute
   358   zadd_ac ~> add_ac
   359   zmult_ac ~> mult_ac
   360   zadd_0 ~> add_0_left
   361   zadd_0_right ~> add_0_right
   362   zadd_zminus_inverse2 ~> left_minus
   363   zmult_zminus ~> mult_minus_left
   364   zmult_commute ~> mult_commute
   365   zmult_assoc ~> mult_assoc
   366   zadd_zmult_distrib ~> left_distrib
   367   zadd_zmult_distrib2 ~> right_distrib
   368   zdiff_zmult_distrib ~> left_diff_distrib
   369   zdiff_zmult_distrib2 ~> right_diff_distrib
   370   zmult_1 ~> mult_1_left
   371   zmult_1_right ~> mult_1_right
   372   zle_refl ~> order_refl
   373   zle_trans ~> order_trans
   374   zle_antisym ~> order_antisym
   375   zle_linear ~> linorder_linear
   376   zless_linear ~> linorder_less_linear
   377   zadd_left_mono ~> add_left_mono
   378   zadd_strict_right_mono ~> add_strict_right_mono
   379   zadd_zless_mono ~> add_less_le_mono
   380   int_0_less_1 ~> zero_less_one
   381   int_0_neq_1 ~> zero_neq_one
   382   zless_le ~> less_le
   383   zpower_zadd_distrib ~> power_add
   384   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   385   zero_le_zpower_abs ~> zero_le_power_abs
   386 
   387 * Theory Deriv: Renamed
   388 
   389   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   390 
   391 * New "case_product" attribute to generate a case rule doing multiple
   392 case distinctions at the same time.  E.g.
   393 
   394   list.exhaust [case_product nat.exhaust]
   395 
   396 produces a rule which can be used to perform case distinction on both
   397 a list and a nat.
   398 
   399 * Improved code generation of multisets.
   400 
   401 * New diagnostic command find_unused_assms to find potentially superfluous
   402   assumptions in theorems using Quickcheck.
   403 
   404 * Quickcheck:
   405   - Quickcheck returns variable assignments as counterexamples, which
   406     allows to reveal the underspecification of functions under test.
   407     For example, refuting "hd xs = x", it presents the variable
   408     assignment xs = [] and x = a1 as a counterexample, assuming that
   409     any property is false whenever "hd []" occurs in it.
   410     These counterexample are marked as potentially spurious, as
   411     Quickcheck also returns "xs = []" as a counterexample to the
   412     obvious theorem "hd xs = hd xs".
   413     After finding a potentially spurious counterexample, Quickcheck
   414     continues searching for genuine ones.
   415     By default, Quickcheck shows potentially spurious and genuine
   416     counterexamples. The option "genuine_only" sets quickcheck to
   417     only show genuine counterexamples.
   418 
   419   - The command 'quickcheck_generator' creates random and exhaustive
   420     value generators for a given type and operations.
   421     It generates values by using the operations as if they were
   422     constructors of that type. 
   423 
   424   - Support for multisets.
   425 
   426   - Added "use_subtype" options.
   427   - Added "quickcheck_locale" configuration to specify how to process
   428     conjectures in a locale context.
   429 
   430 * Nitpick:
   431   - Fixed infinite loop caused by the 'peephole_optim' option and
   432     affecting 'rat' and 'real'.
   433 
   434 * Sledgehammer:
   435   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   436   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   437   - Renamed "sound" option to "strict".
   438 
   439 * Metis:
   440   - Added possibility to specify lambda translations scheme as a
   441     parenthesized argument (e.g., "by (metis (lifting) ...)").
   442 
   443 * SMT:
   444   - renamed "smt_fixed" option to "smt_read_only_certificates".
   445  
   446 * Command 'try0':
   447   - Renamed from 'try_methods'. INCOMPATIBILITY.
   448 
   449 * New "eventually_elim" method as a generalized variant of the
   450   eventually_elim* rules. Supports structured proofs.
   451 
   452 
   453 *** FOL ***
   454 
   455 * New "case_product" attribute (see HOL).
   456 
   457 
   458 *** ML ***
   459 
   460 * Antiquotation @{keyword "name"} produces a parser for outer syntax
   461 from a minor keyword introduced via theory header declaration.
   462 
   463 * Antiquotation @{command_spec "name"} produces the
   464 Outer_Syntax.command_spec from a major keyword introduced via theory
   465 header declaration; it can be passed to Outer_Syntax.command etc.
   466 
   467 * Local_Theory.define no longer hard-wires default theorem name
   468 "foo_def", but retains the binding as given.  If that is Binding.empty
   469 / Attrib.empty_binding, the result is not registered as user-level
   470 fact.  The Local_Theory.define_internal variant allows to specify a
   471 non-empty name (used for the foundation in the background theory),
   472 while omitting the fact binding in the user-context.  Potential
   473 INCOMPATIBILITY for derived definitional packages: need to specify
   474 naming policy for primitive definitions more explicitly.
   475 
   476 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
   477 conformance with similar operations in structure Term and Logic.
   478 
   479 * Antiquotation @{attributes [...]} embeds attribute source
   480 representation into the ML text, which is particularly useful with
   481 declarations like Local_Theory.note.
   482 
   483 * Structure Proof_Context follows standard naming scheme.  Old
   484 ProofContext has been discontinued.  INCOMPATIBILITY.
   485 
   486 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   487 change of semantics: update is applied to auxiliary local theory
   488 context as well.
   489 
   490 * Modernized some old-style infix operations:
   491 
   492   addeqcongs    ~> Simplifier.add_eqcong
   493   deleqcongs    ~> Simplifier.del_eqcong
   494   addcongs      ~> Simplifier.add_cong
   495   delcongs      ~> Simplifier.del_cong
   496   setmksimps    ~> Simplifier.set_mksimps
   497   setmkcong     ~> Simplifier.set_mkcong
   498   setmksym      ~> Simplifier.set_mksym
   499   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   500   settermless   ~> Simplifier.set_termless
   501   setsubgoaler  ~> Simplifier.set_subgoaler
   502   addsplits     ~> Splitter.add_split
   503   delsplits     ~> Splitter.del_split
   504 
   505 
   506 
   507 New in Isabelle2011-1 (October 2011)
   508 ------------------------------------
   509 
   510 *** General ***
   511 
   512 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   513 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   514 
   515   - Management of multiple theory files directly from the editor
   516     buffer store -- bypassing the file-system (no requirement to save
   517     files for checking).
   518 
   519   - Markup of formal entities within the text buffer, with semantic
   520     highlighting, tooltips and hyperlinks to jump to defining source
   521     positions.
   522 
   523   - Improved text rendering, with sub/superscripts in the source
   524     buffer (including support for copy/paste wrt. output panel, HTML
   525     theory output and other non-Isabelle text boxes).
   526 
   527   - Refined scheduling of proof checking and printing of results,
   528     based on interactive editor view.  (Note: jEdit folding and
   529     narrowing allows to restrict buffer perspectives explicitly.)
   530 
   531   - Reduced CPU performance requirements, usable on machines with few
   532     cores.
   533 
   534   - Reduced memory requirements due to pruning of unused document
   535     versions (garbage collection).
   536 
   537 See also ~~/src/Tools/jEdit/README.html for further information,
   538 including some remaining limitations.
   539 
   540 * Theory loader: source files are exclusively located via the master
   541 directory of each theory node (where the .thy file itself resides).
   542 The global load path (such as src/HOL/Library) has been discontinued.
   543 Note that the path element ~~ may be used to reference theories in the
   544 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   545 INCOMPATIBILITY.
   546 
   547 * Theory loader: source files are identified by content via SHA1
   548 digests.  Discontinued former path/modtime identification and optional
   549 ISABELLE_FILE_IDENT plugin scripts.
   550 
   551 * Parallelization of nested Isar proofs is subject to
   552 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   553 usedir option -Q.
   554 
   555 * Name space: former unsynchronized references are now proper
   556 configuration options, with more conventional names:
   557 
   558   long_names   ~> names_long
   559   short_names  ~> names_short
   560   unique_names ~> names_unique
   561 
   562 Minor INCOMPATIBILITY, need to declare options in context like this:
   563 
   564   declare [[names_unique = false]]
   565 
   566 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   567 that the result needs to be unique, which means fact specifications
   568 may have to be refined after enriching a proof context.
   569 
   570 * Attribute "case_names" has been refined: the assumptions in each case
   571 can be named now by following the case name with [name1 name2 ...].
   572 
   573 * Isabelle/Isar reference manual has been updated and extended:
   574   - "Synopsis" provides a catalog of main Isar language concepts.
   575   - Formal references in syntax diagrams, via @{rail} antiquotation.
   576   - Updated material from classic "ref" manual, notably about
   577     "Classical Reasoner".
   578 
   579 
   580 *** HOL ***
   581 
   582 * Class bot and top require underlying partial order rather than
   583 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   584 
   585 * Class complete_lattice: generalized a couple of lemmas from sets;
   586 generalized theorems INF_cong and SUP_cong.  New type classes for
   587 complete boolean algebras and complete linear orders.  Lemmas
   588 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   589 class complete_linorder.
   590 
   591 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   592 Sup_fun_def, Inf_apply, Sup_apply.
   593 
   594 Removed redundant lemmas (the right hand side gives hints how to
   595 replace them for (metis ...), or (simp only: ...) proofs):
   596 
   597   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   598   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   599   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   600   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   601   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   602   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   603   Inter_def ~> INF_def, image_def
   604   Union_def ~> SUP_def, image_def
   605   INT_eq ~> INF_def, and image_def
   606   UN_eq ~> SUP_def, and image_def
   607   INF_subset ~> INF_superset_mono [OF _ order_refl]
   608 
   609 More consistent and comprehensive names:
   610 
   611   INTER_eq_Inter_image ~> INF_def
   612   UNION_eq_Union_image ~> SUP_def
   613   INFI_def ~> INF_def
   614   SUPR_def ~> SUP_def
   615   INF_leI ~> INF_lower
   616   INF_leI2 ~> INF_lower2
   617   le_INFI ~> INF_greatest
   618   le_SUPI ~> SUP_upper
   619   le_SUPI2 ~> SUP_upper2
   620   SUP_leI ~> SUP_least
   621   INFI_bool_eq ~> INF_bool_eq
   622   SUPR_bool_eq ~> SUP_bool_eq
   623   INFI_apply ~> INF_apply
   624   SUPR_apply ~> SUP_apply
   625   INTER_def ~> INTER_eq
   626   UNION_def ~> UNION_eq
   627 
   628 INCOMPATIBILITY.
   629 
   630 * Renamed theory Complete_Lattice to Complete_Lattices.
   631 INCOMPATIBILITY.
   632 
   633 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   634 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   635 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   636 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   637 
   638 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   639 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   640 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   641 INCOMPATIBILITY.
   642 
   643 * Added syntactic classes "inf" and "sup" for the respective
   644 constants.  INCOMPATIBILITY: Changes in the argument order of the
   645 (mostly internal) locale predicates for some derived classes.
   646 
   647 * Theorem collections ball_simps and bex_simps do not contain theorems
   648 referring to UNION any longer; these have been moved to collection
   649 UN_ball_bex_simps.  INCOMPATIBILITY.
   650 
   651 * Theory Archimedean_Field: floor now is defined as parameter of a
   652 separate type class floor_ceiling.
   653 
   654 * Theory Finite_Set: more coherent development of fold_set locales:
   655 
   656     locale fun_left_comm ~> locale comp_fun_commute
   657     locale fun_left_comm_idem ~> locale comp_fun_idem
   658 
   659 Both use point-free characterization; interpretation proofs may need
   660 adjustment.  INCOMPATIBILITY.
   661 
   662 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   663 accordance with standard mathematical terminology. INCOMPATIBILITY.
   664 
   665 * Theory Complex_Main: The locale interpretations for the
   666 bounded_linear and bounded_bilinear locales have been removed, in
   667 order to reduce the number of duplicate lemmas. Users must use the
   668 original names for distributivity theorems, potential INCOMPATIBILITY.
   669 
   670   divide.add ~> add_divide_distrib
   671   divide.diff ~> diff_divide_distrib
   672   divide.setsum ~> setsum_divide_distrib
   673   mult.add_right ~> right_distrib
   674   mult.diff_right ~> right_diff_distrib
   675   mult_right.setsum ~> setsum_right_distrib
   676   mult_left.diff ~> left_diff_distrib
   677 
   678 * Theory Complex_Main: Several redundant theorems have been removed or
   679 replaced by more general versions. INCOMPATIBILITY.
   680 
   681   real_diff_def ~> minus_real_def
   682   real_divide_def ~> divide_real_def
   683   real_less_def ~> less_le
   684   real_abs_def ~> abs_real_def
   685   real_sgn_def ~> sgn_real_def
   686   real_mult_commute ~> mult_commute
   687   real_mult_assoc ~> mult_assoc
   688   real_mult_1 ~> mult_1_left
   689   real_add_mult_distrib ~> left_distrib
   690   real_zero_not_eq_one ~> zero_neq_one
   691   real_mult_inverse_left ~> left_inverse
   692   INVERSE_ZERO ~> inverse_zero
   693   real_le_refl ~> order_refl
   694   real_le_antisym ~> order_antisym
   695   real_le_trans ~> order_trans
   696   real_le_linear ~> linear
   697   real_le_eq_diff ~> le_iff_diff_le_0
   698   real_add_left_mono ~> add_left_mono
   699   real_mult_order ~> mult_pos_pos
   700   real_mult_less_mono2 ~> mult_strict_left_mono
   701   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   702   real_0_le_divide_iff ~> zero_le_divide_iff
   703   realpow_two_disj ~> power2_eq_iff
   704   real_squared_diff_one_factored ~> square_diff_one_factored
   705   realpow_two_diff ~> square_diff_square_factored
   706   reals_complete2 ~> complete_real
   707   real_sum_squared_expand ~> power2_sum
   708   exp_ln_eq ~> ln_unique
   709   expi_add ~> exp_add
   710   expi_zero ~> exp_zero
   711   lemma_DERIV_subst ~> DERIV_cong
   712   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   713   LIMSEQ_const ~> tendsto_const
   714   LIMSEQ_norm ~> tendsto_norm
   715   LIMSEQ_add ~> tendsto_add
   716   LIMSEQ_minus ~> tendsto_minus
   717   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   718   LIMSEQ_diff ~> tendsto_diff
   719   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   720   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   721   LIMSEQ_mult ~> tendsto_mult
   722   LIMSEQ_inverse ~> tendsto_inverse
   723   LIMSEQ_divide ~> tendsto_divide
   724   LIMSEQ_pow ~> tendsto_power
   725   LIMSEQ_setsum ~> tendsto_setsum
   726   LIMSEQ_setprod ~> tendsto_setprod
   727   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   728   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   729   LIMSEQ_imp_rabs ~> tendsto_rabs
   730   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   731   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   732   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   733   LIMSEQ_Complex ~> tendsto_Complex
   734   LIM_ident ~> tendsto_ident_at
   735   LIM_const ~> tendsto_const
   736   LIM_add ~> tendsto_add
   737   LIM_add_zero ~> tendsto_add_zero
   738   LIM_minus ~> tendsto_minus
   739   LIM_diff ~> tendsto_diff
   740   LIM_norm ~> tendsto_norm
   741   LIM_norm_zero ~> tendsto_norm_zero
   742   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   743   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   744   LIM_rabs ~> tendsto_rabs
   745   LIM_rabs_zero ~> tendsto_rabs_zero
   746   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   747   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   748   LIM_compose ~> tendsto_compose
   749   LIM_mult ~> tendsto_mult
   750   LIM_scaleR ~> tendsto_scaleR
   751   LIM_of_real ~> tendsto_of_real
   752   LIM_power ~> tendsto_power
   753   LIM_inverse ~> tendsto_inverse
   754   LIM_sgn ~> tendsto_sgn
   755   isCont_LIM_compose ~> isCont_tendsto_compose
   756   bounded_linear.LIM ~> bounded_linear.tendsto
   757   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   758   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   759   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   760   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   761   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   762   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   763 
   764 * Theory Complex_Main: The definition of infinite series was
   765 generalized.  Now it is defined on the type class {topological_space,
   766 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   767 
   768 * Theory Complex_Main: The complex exponential function "expi" is now
   769 a type-constrained abbreviation for "exp :: complex => complex"; thus
   770 several polymorphic lemmas about "exp" are now applicable to "expi".
   771 
   772 * Code generation:
   773 
   774   - Theory Library/Code_Char_ord provides native ordering of
   775     characters in the target language.
   776 
   777   - Commands code_module and code_library are legacy, use export_code
   778     instead.
   779 
   780   - Method "evaluation" is legacy, use method "eval" instead.
   781 
   782   - Legacy evaluator "SML" is deactivated by default.  May be
   783     reactivated by the following theory command:
   784 
   785       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   786 
   787 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   788 
   789 * New proof method "induction" that gives induction hypotheses the
   790 name "IH", thus distinguishing them from further hypotheses that come
   791 from rule induction.  The latter are still called "hyps".  Method
   792 "induction" is a thin wrapper around "induct" and follows the same
   793 syntax.
   794 
   795 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
   796 still available as a legacy feature for some time.
   797 
   798 * Nitpick:
   799   - Added "need" and "total_consts" options.
   800   - Reintroduced "show_skolems" option by popular demand.
   801   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   802     INCOMPATIBILITY.
   803 
   804 * Sledgehammer:
   805   - Use quasi-sound (and efficient) translations by default.
   806   - Added support for the following provers: E-ToFoF, LEO-II,
   807     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
   808   - Automatically preplay and minimize proofs before showing them if
   809     this can be done within reasonable time.
   810   - sledgehammer available_provers ~> sledgehammer supported_provers.
   811     INCOMPATIBILITY.
   812   - Added "preplay_timeout", "slicing", "type_enc", "sound",
   813     "max_mono_iters", and "max_new_mono_instances" options.
   814   - Removed "explicit_apply" and "full_types" options as well as "Full
   815     Types" Proof General menu item. INCOMPATIBILITY.
   816 
   817 * Metis:
   818   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   819   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
   820     INCOMPATIBILITY.
   821 
   822 * Command 'try':
   823   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
   824     "elim:" options. INCOMPATIBILITY.
   825   - Introduced 'try' that not only runs 'try_methods' but also
   826     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
   827 
   828 * Quickcheck:
   829   - Added "eval" option to evaluate terms for the found counterexample
   830     (currently only supported by the default (exhaustive) tester).
   831   - Added post-processing of terms to obtain readable counterexamples
   832     (currently only supported by the default (exhaustive) tester).
   833   - New counterexample generator quickcheck[narrowing] enables
   834     narrowing-based testing.  Requires the Glasgow Haskell compiler
   835     with its installation location defined in the Isabelle settings
   836     environment as ISABELLE_GHC.
   837   - Removed quickcheck tester "SML" based on the SML code generator
   838     (formly in HOL/Library).
   839 
   840 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
   841 use 'partial_function' instead.
   842 
   843 * Theory Library/Extended_Reals replaces now the positive extended
   844 reals found in probability theory. This file is extended by
   845 Multivariate_Analysis/Extended_Real_Limits.
   846 
   847 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
   848 from where it must be imported explicitly if it is really required.
   849 INCOMPATIBILITY.
   850 
   851 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
   852 been moved here.  INCOMPATIBILITY.
   853 
   854 * Theory Library/Saturated provides type of numbers with saturated
   855 arithmetic.
   856 
   857 * Theory Library/Product_Lattice defines a pointwise ordering for the
   858 product type 'a * 'b, and provides instance proofs for various order
   859 and lattice type classes.
   860 
   861 * Theory Library/Countable now provides the "countable_datatype" proof
   862 method for proving "countable" class instances for datatypes.
   863 
   864 * Theory Library/Cset_Monad allows do notation for computable sets
   865 (cset) via the generic monad ad-hoc overloading facility.
   866 
   867 * Library: Theories of common data structures are split into theories
   868 for implementation, an invariant-ensuring type, and connection to an
   869 abstract type. INCOMPATIBILITY.
   870 
   871   - RBT is split into RBT and RBT_Mapping.
   872   - AssocList is split and renamed into AList and AList_Mapping.
   873   - DList is split into DList_Impl, DList, and DList_Cset.
   874   - Cset is split into Cset and List_Cset.
   875 
   876 * Theory Library/Nat_Infinity has been renamed to
   877 Library/Extended_Nat, with name changes of the following types and
   878 constants:
   879 
   880   type inat   ~> type enat
   881   Fin         ~> enat
   882   Infty       ~> infinity (overloaded)
   883   iSuc        ~> eSuc
   884   the_Fin     ~> the_enat
   885 
   886 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   887 been renamed accordingly. INCOMPATIBILITY.
   888 
   889 * Session Multivariate_Analysis: The euclidean_space type class now
   890 fixes a constant "Basis :: 'a set" consisting of the standard
   891 orthonormal basis for the type. Users now have the option of
   892 quantifying over this set instead of using the "basis" function, e.g.
   893 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
   894 
   895 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   896 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   897 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   898 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   899 changed to match. Definition theorems for overloaded constants now use
   900 the standard "foo_vec_def" naming scheme. A few other theorems have
   901 been renamed as follows (INCOMPATIBILITY):
   902 
   903   Cart_eq          ~> vec_eq_iff
   904   dist_nth_le_cart ~> dist_vec_nth_le
   905   tendsto_vector   ~> vec_tendstoI
   906   Cauchy_vector    ~> vec_CauchyI
   907 
   908 * Session Multivariate_Analysis: Several duplicate theorems have been
   909 removed, and other theorems have been renamed or replaced with more
   910 general versions. INCOMPATIBILITY.
   911 
   912   finite_choice ~> finite_set_choice
   913   eventually_conjI ~> eventually_conj
   914   eventually_and ~> eventually_conj_iff
   915   eventually_false ~> eventually_False
   916   setsum_norm ~> norm_setsum
   917   Lim_sequentially ~> LIMSEQ_def
   918   Lim_ident_at ~> LIM_ident
   919   Lim_const ~> tendsto_const
   920   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   921   Lim_neg ~> tendsto_minus
   922   Lim_add ~> tendsto_add
   923   Lim_sub ~> tendsto_diff
   924   Lim_mul ~> tendsto_scaleR
   925   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   926   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   927   Lim_linear ~> bounded_linear.tendsto
   928   Lim_component ~> tendsto_euclidean_component
   929   Lim_component_cart ~> tendsto_vec_nth
   930   Lim_inner ~> tendsto_inner [OF tendsto_const]
   931   dot_lsum ~> inner_setsum_left
   932   dot_rsum ~> inner_setsum_right
   933   continuous_cmul ~> continuous_scaleR [OF continuous_const]
   934   continuous_neg ~> continuous_minus
   935   continuous_sub ~> continuous_diff
   936   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
   937   continuous_mul ~> continuous_scaleR
   938   continuous_inv ~> continuous_inverse
   939   continuous_at_within_inv ~> continuous_at_within_inverse
   940   continuous_at_inv ~> continuous_at_inverse
   941   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
   942   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
   943   continuous_at_component ~> continuous_component [OF continuous_at_id]
   944   continuous_on_neg ~> continuous_on_minus
   945   continuous_on_sub ~> continuous_on_diff
   946   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   947   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   948   continuous_on_mul ~> continuous_on_scaleR
   949   continuous_on_mul_real ~> continuous_on_mult
   950   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   951   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
   952   continuous_on_inverse ~> continuous_on_inv
   953   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
   954   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
   955   subset_interior ~> interior_mono
   956   subset_closure ~> closure_mono
   957   closure_univ ~> closure_UNIV
   958   real_arch_lt ~> reals_Archimedean2
   959   real_arch ~> reals_Archimedean3
   960   real_abs_norm ~> abs_norm_cancel
   961   real_abs_sub_norm ~> norm_triangle_ineq3
   962   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
   963 
   964 * Session HOL-Probability:
   965   - Caratheodory's extension lemma is now proved for ring_of_sets.
   966   - Infinite products of probability measures are now available.
   967   - Sigma closure is independent, if the generator is independent
   968   - Use extended reals instead of positive extended
   969     reals. INCOMPATIBILITY.
   970 
   971 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
   972 
   973   expand_fun_below ~> fun_below_iff
   974   below_fun_ext ~> fun_belowI
   975   expand_cfun_eq ~> cfun_eq_iff
   976   ext_cfun ~> cfun_eqI
   977   expand_cfun_below ~> cfun_below_iff
   978   below_cfun_ext ~> cfun_belowI
   979   monofun_fun_fun ~> fun_belowD
   980   monofun_fun_arg ~> monofunE
   981   monofun_lub_fun ~> adm_monofun [THEN admD]
   982   cont_lub_fun ~> adm_cont [THEN admD]
   983   cont2cont_Rep_CFun ~> cont2cont_APP
   984   cont_Rep_CFun_app ~> cont_APP_app
   985   cont_Rep_CFun_app_app ~> cont_APP_app_app
   986   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
   987   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
   988   contlub_cfun ~> lub_APP [symmetric]
   989   contlub_LAM ~> lub_LAM [symmetric]
   990   thelubI ~> lub_eqI
   991   UU_I ~> bottomI
   992   lift_distinct1 ~> lift.distinct(1)
   993   lift_distinct2 ~> lift.distinct(2)
   994   Def_not_UU ~> lift.distinct(2)
   995   Def_inject ~> lift.inject
   996   below_UU_iff ~> below_bottom_iff
   997   eq_UU_iff ~> eq_bottom_iff
   998 
   999 
  1000 *** Document preparation ***
  1001 
  1002 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
  1003 isar-ref manual, both for description and actual application of the
  1004 same.
  1005 
  1006 * Antiquotation @{value} evaluates the given term and presents its
  1007 result.
  1008 
  1009 * Antiquotations: term style "isub" provides ad-hoc conversion of
  1010 variables x1, y23 into subscripted form x\<^isub>1,
  1011 y\<^isub>2\<^isub>3.
  1012 
  1013 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
  1014 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
  1015 
  1016 * Localized \isabellestyle switch can be used within blocks or groups
  1017 like this:
  1018 
  1019   \isabellestyle{it}  %preferred default
  1020   {\isabellestylett @{text "typewriter stuff"}}
  1021 
  1022 * Discontinued special treatment of hard tabulators.  Implicit
  1023 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
  1024 layouts.
  1025 
  1026 
  1027 *** ML ***
  1028 
  1029 * The inner syntax of sort/type/term/prop supports inlined YXML
  1030 representations within quoted string tokens.  By encoding logical
  1031 entities via Term_XML (in ML or Scala) concrete syntax can be
  1032 bypassed, which is particularly useful for producing bits of text
  1033 under external program control.
  1034 
  1035 * Antiquotations for ML and document preparation are managed as theory
  1036 data, which requires explicit setup.
  1037 
  1038 * Isabelle_Process.is_active allows tools to check if the official
  1039 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
  1040 (better known as Proof General).
  1041 
  1042 * Structure Proof_Context follows standard naming scheme.  Old
  1043 ProofContext is still available for some time as legacy alias.
  1044 
  1045 * Structure Timing provides various operations for timing; supersedes
  1046 former start_timing/end_timing etc.
  1047 
  1048 * Path.print is the official way to show file-system paths to users
  1049 (including quotes etc.).
  1050 
  1051 * Inner syntax: identifiers in parse trees of generic categories
  1052 "logic", "aprop", "idt" etc. carry position information (disguised as
  1053 type constraints).  Occasional INCOMPATIBILITY with non-compliant
  1054 translations that choke on unexpected type constraints.  Positions can
  1055 be stripped in ML translations via Syntax.strip_positions /
  1056 Syntax.strip_positions_ast, or via the syntax constant
  1057 "_strip_positions" within parse trees.  As last resort, positions can
  1058 be disabled via the configuration option Syntax.positions, which is
  1059 called "syntax_positions" in Isar attribute syntax.
  1060 
  1061 * Discontinued special status of various ML structures that contribute
  1062 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
  1063 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
  1064 refer directly to Ast.Constant, Lexicon.is_identifier,
  1065 Syntax_Trans.mk_binder_tr etc.
  1066 
  1067 * Typed print translation: discontinued show_sorts argument, which is
  1068 already available via context of "advanced" translation.
  1069 
  1070 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
  1071 goal states; body tactic needs to address all subgoals uniformly.
  1072 
  1073 * Slightly more special eq_list/eq_set, with shortcut involving
  1074 pointer equality (assumes that eq relation is reflexive).
  1075 
  1076 * Classical tactics use proper Proof.context instead of historic types
  1077 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  1078 operate directly on Proof.context.  Raw type claset retains its use as
  1079 snapshot of the classical context, which can be recovered via
  1080 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  1081 INCOMPATIBILITY, classical tactics and derived proof methods require
  1082 proper Proof.context.
  1083 
  1084 
  1085 *** System ***
  1086 
  1087 * Discontinued support for Poly/ML 5.2, which was the last version
  1088 without proper multithreading and TimeLimit implementation.
  1089 
  1090 * Discontinued old lib/scripts/polyml-platform, which has been
  1091 obsolete since Isabelle2009-2.
  1092 
  1093 * Various optional external tools are referenced more robustly and
  1094 uniformly by explicit Isabelle settings as follows:
  1095 
  1096   ISABELLE_CSDP   (formerly CSDP_EXE)
  1097   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  1098   ISABELLE_OCAML  (formerly EXEC_OCAML)
  1099   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  1100   ISABELLE_YAP    (formerly EXEC_YAP)
  1101 
  1102 Note that automated detection from the file-system or search path has
  1103 been discontinued.  INCOMPATIBILITY.
  1104 
  1105 * Scala layer provides JVM method invocation service for static
  1106 methods of type (String)String, see Invoke_Scala.method in ML.  For
  1107 example:
  1108 
  1109   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  1110 
  1111 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  1112 this allows to pass structured values between ML and Scala.
  1113 
  1114 * The IsabelleText fonts includes some further glyphs to support the
  1115 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  1116 installed a local copy (which is normally *not* required) need to
  1117 delete or update it from ~~/lib/fonts/.
  1118 
  1119 
  1120 
  1121 New in Isabelle2011 (January 2011)
  1122 ----------------------------------
  1123 
  1124 *** General ***
  1125 
  1126 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  1127 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  1128 useful tooltips and hyperlinks produced from its static analysis.  The
  1129 bundled component provides an executable Isabelle tool that can be run
  1130 like this:
  1131 
  1132   Isabelle2011/bin/isabelle jedit
  1133 
  1134 * Significantly improved Isabelle/Isar implementation manual.
  1135 
  1136 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  1137 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  1138 while the default heap location within that directory lacks that extra
  1139 suffix.  This isolates multiple Isabelle installations from each
  1140 other, avoiding problems with old settings in new versions.
  1141 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  1142 
  1143 * Source files are always encoded as UTF-8, instead of old-fashioned
  1144 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  1145 the following package declarations:
  1146 
  1147   \usepackage[utf8]{inputenc}
  1148   \usepackage{textcomp}
  1149 
  1150 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  1151 a Unicode character is treated as a single symbol, not a sequence of
  1152 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  1153 contain symbols without further backslash escapes, Unicode can now be
  1154 used here as well.  Recall that Symbol.explode in ML provides a
  1155 consistent view on symbols, while raw explode (or String.explode)
  1156 merely give a byte-oriented representation.
  1157 
  1158 * Theory loader: source files are primarily located via the master
  1159 directory of each theory node (where the .thy file itself resides).
  1160 The global load path is still partially available as legacy feature.
  1161 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  1162 explicit paths, relatively to the theory.
  1163 
  1164 * Special treatment of ML file names has been discontinued.
  1165 Historically, optional extensions .ML or .sml were added on demand --
  1166 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  1167 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  1168 
  1169 * Various options that affect pretty printing etc. are now properly
  1170 handled within the context via configuration options, instead of
  1171 unsynchronized references or print modes.  There are both ML Config.T
  1172 entities and Isar declaration attributes to access these.
  1173 
  1174   ML (Config.T)                 Isar (attribute)
  1175 
  1176   eta_contract                  eta_contract
  1177   show_brackets                 show_brackets
  1178   show_sorts                    show_sorts
  1179   show_types                    show_types
  1180   show_question_marks           show_question_marks
  1181   show_consts                   show_consts
  1182   show_abbrevs                  show_abbrevs
  1183 
  1184   Syntax.ast_trace              syntax_ast_trace
  1185   Syntax.ast_stat               syntax_ast_stat
  1186   Syntax.ambiguity_level        syntax_ambiguity_level
  1187 
  1188   Goal_Display.goals_limit      goals_limit
  1189   Goal_Display.show_main_goal   show_main_goal
  1190 
  1191   Method.rule_trace             rule_trace
  1192 
  1193   Thy_Output.display            thy_output_display
  1194   Thy_Output.quotes             thy_output_quotes
  1195   Thy_Output.indent             thy_output_indent
  1196   Thy_Output.source             thy_output_source
  1197   Thy_Output.break              thy_output_break
  1198 
  1199 Note that corresponding "..._default" references in ML may only be
  1200 changed globally at the ROOT session setup, but *not* within a theory.
  1201 The option "show_abbrevs" supersedes the former print mode
  1202 "no_abbrevs" with inverted meaning.
  1203 
  1204 * More systematic naming of some configuration options.
  1205 INCOMPATIBILITY.
  1206 
  1207   trace_simp  ~>  simp_trace
  1208   debug_simp  ~>  simp_debug
  1209 
  1210 * Support for real valued configuration options, using simplistic
  1211 floating-point notation that coincides with the inner syntax for
  1212 float_token.
  1213 
  1214 * Support for real valued preferences (with approximative PGIP type):
  1215 front-ends need to accept "pgint" values in float notation.
  1216 INCOMPATIBILITY.
  1217 
  1218 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  1219 DejaVu Sans.
  1220 
  1221 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  1222 
  1223 
  1224 *** Pure ***
  1225 
  1226 * Command 'type_synonym' (with single argument) replaces somewhat
  1227 outdated 'types', which is still available as legacy feature for some
  1228 time.
  1229 
  1230 * Command 'nonterminal' (with 'and' separated list of arguments)
  1231 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  1232 
  1233 * Command 'notepad' replaces former 'example_proof' for
  1234 experimentation in Isar without any result.  INCOMPATIBILITY.
  1235 
  1236 * Locale interpretation commands 'interpret' and 'sublocale' accept
  1237 lists of equations to map definitions in a locale to appropriate
  1238 entities in the context of the interpretation.  The 'interpretation'
  1239 command already provided this functionality.
  1240 
  1241 * Diagnostic command 'print_dependencies' prints the locale instances
  1242 that would be activated if the specified expression was interpreted in
  1243 the current context.  Variant "print_dependencies!" assumes a context
  1244 without interpretations.
  1245 
  1246 * Diagnostic command 'print_interps' prints interpretations in proofs
  1247 in addition to interpretations in theories.
  1248 
  1249 * Discontinued obsolete 'global' and 'local' commands to manipulate
  1250 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  1251 Sign.root_path and Sign.local_path may be applied directly where this
  1252 feature is still required for historical reasons.
  1253 
  1254 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  1255 'definition' instead.
  1256 
  1257 * The "prems" fact, which refers to the accidental collection of
  1258 foundational premises in the context, is now explicitly marked as
  1259 legacy feature and will be discontinued soon.  Consider using "assms"
  1260 of the head statement or reference facts by explicit names.
  1261 
  1262 * Document antiquotations @{class} and @{type} print classes and type
  1263 constructors.
  1264 
  1265 * Document antiquotation @{file} checks file/directory entries within
  1266 the local file system.
  1267 
  1268 
  1269 *** HOL ***
  1270 
  1271 * Coercive subtyping: functions can be declared as coercions and type
  1272 inference will add them as necessary upon input of a term.  Theory
  1273 Complex_Main declares real :: nat => real and real :: int => real as
  1274 coercions. A coercion function f is declared like this:
  1275 
  1276   declare [[coercion f]]
  1277 
  1278 To lift coercions through type constructors (e.g. from nat => real to
  1279 nat list => real list), map functions can be declared, e.g.
  1280 
  1281   declare [[coercion_map map]]
  1282 
  1283 Currently coercion inference is activated only in theories including
  1284 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1285 the configuration option "coercion_enabled", e.g. it can be enabled in
  1286 other theories like this:
  1287 
  1288   declare [[coercion_enabled]]
  1289 
  1290 * Command 'partial_function' provides basic support for recursive
  1291 function definitions over complete partial orders.  Concrete instances
  1292 are provided for i) the option type, ii) tail recursion on arbitrary
  1293 types, and iii) the heap monad of Imperative_HOL.  See
  1294 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1295 for examples.
  1296 
  1297 * Function package: f.psimps rules are no longer implicitly declared
  1298 as [simp].  INCOMPATIBILITY.
  1299 
  1300 * Datatype package: theorems generated for executable equality (class
  1301 "eq") carry proper names and are treated as default code equations.
  1302 
  1303 * Inductive package: now offers command 'inductive_simps' to
  1304 automatically derive instantiated and simplified equations for
  1305 inductive predicates, similar to 'inductive_cases'.
  1306 
  1307 * Command 'enriched_type' allows to register properties of the
  1308 functorial structure of types.
  1309 
  1310 * Improved infrastructure for term evaluation using code generator
  1311 techniques, in particular static evaluation conversions.
  1312 
  1313 * Code generator: Scala (2.8 or higher) has been added to the target
  1314 languages.
  1315 
  1316 * Code generator: globbing constant expressions "*" and "Theory.*"
  1317 have been replaced by the more idiomatic "_" and "Theory._".
  1318 INCOMPATIBILITY.
  1319 
  1320 * Code generator: export_code without explicit file declaration prints
  1321 to standard output.  INCOMPATIBILITY.
  1322 
  1323 * Code generator: do not print function definitions for case
  1324 combinators any longer.
  1325 
  1326 * Code generator: simplification with rules determined with
  1327 src/Tools/Code/code_simp.ML and method "code_simp".
  1328 
  1329 * Code generator for records: more idiomatic representation of record
  1330 types.  Warning: records are not covered by ancient SML code
  1331 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1332 rep_datatype declaration helps to succeed then:
  1333 
  1334   record 'a foo = ...
  1335   ...
  1336   rep_datatype foo_ext ...
  1337 
  1338 * Records: logical foundation type for records does not carry a
  1339 '_type' suffix any longer (obsolete due to authentic syntax).
  1340 INCOMPATIBILITY.
  1341 
  1342 * Quickcheck now by default uses exhaustive testing instead of random
  1343 testing.  Random testing can be invoked by "quickcheck [random]",
  1344 exhaustive testing by "quickcheck [exhaustive]".
  1345 
  1346 * Quickcheck instantiates polymorphic types with small finite
  1347 datatypes by default. This enables a simple execution mechanism to
  1348 handle quantifiers and function equality over the finite datatypes.
  1349 
  1350 * Quickcheck random generator has been renamed from "code" to
  1351 "random".  INCOMPATIBILITY.
  1352 
  1353 * Quickcheck now has a configurable time limit which is set to 30
  1354 seconds by default. This can be changed by adding [timeout = n] to the
  1355 quickcheck command. The time limit for Auto Quickcheck is still set
  1356 independently.
  1357 
  1358 * Quickcheck in locales considers interpretations of that locale for
  1359 counter example search.
  1360 
  1361 * Sledgehammer:
  1362   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1363     method. See the Sledgehammer manual for details ("isabelle doc
  1364     sledgehammer").
  1365   - Renamed commands:
  1366     sledgehammer atp_info ~> sledgehammer running_provers
  1367     sledgehammer atp_kill ~> sledgehammer kill_provers
  1368     sledgehammer available_atps ~> sledgehammer available_provers
  1369     INCOMPATIBILITY.
  1370   - Renamed options:
  1371     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1372     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1373     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1374     (and "ms" and "min" are no longer supported)
  1375     INCOMPATIBILITY.
  1376 
  1377 * Nitpick:
  1378   - Renamed options:
  1379     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1380     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1381     INCOMPATIBILITY.
  1382   - Added support for partial quotient types.
  1383   - Added local versions of the "Nitpick.register_xxx" functions.
  1384   - Added "whack" option.
  1385   - Allow registration of quotient types as codatatypes.
  1386   - Improved "merge_type_vars" option to merge more types.
  1387   - Removed unsound "fast_descrs" option.
  1388   - Added custom symmetry breaking for datatypes, making it possible to reach
  1389     higher cardinalities.
  1390   - Prevent the expansion of too large definitions.
  1391 
  1392 * Proof methods "metis" and "meson" now have configuration options
  1393 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1394 to diagnose these tools. E.g.
  1395 
  1396     using [[metis_trace = true]]
  1397 
  1398 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1399 manually as command 'solve_direct'.
  1400 
  1401 * The default SMT solver Z3 must be enabled explicitly (due to
  1402 licensing issues) by setting the environment variable
  1403 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1404 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1405 changing the SMT solver is done via the configuration option
  1406 "smt_solver".
  1407 
  1408 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1409 i.e. "remote_cvc3" and "remote_z3".
  1410 
  1411 * Added basic SMT support for datatypes, records, and typedefs using
  1412 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1413 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1414 support for a similar behavior).  Minor INCOMPATIBILITY.
  1415 
  1416 * Changed SMT configuration options:
  1417   - Renamed:
  1418     z3_proofs ~> smt_oracle (with inverted meaning)
  1419     z3_trace_assms ~> smt_trace_used_facts
  1420     INCOMPATIBILITY.
  1421   - Added:
  1422     smt_verbose
  1423     smt_random_seed
  1424     smt_datatypes
  1425     smt_infer_triggers
  1426     smt_monomorph_limit
  1427     cvc3_options
  1428     remote_cvc3_options
  1429     remote_z3_options
  1430     yices_options
  1431 
  1432 * Boogie output files (.b2i files) need to be declared in the theory
  1433 header.
  1434 
  1435 * Simplification procedure "list_to_set_comprehension" rewrites list
  1436 comprehensions applied to List.set to set comprehensions.  Occasional
  1437 INCOMPATIBILITY, may be deactivated like this:
  1438 
  1439   declare [[simproc del: list_to_set_comprehension]]
  1440 
  1441 * Removed old version of primrec package.  INCOMPATIBILITY.
  1442 
  1443 * Removed simplifier congruence rule of "prod_case", as has for long
  1444 been the case with "split".  INCOMPATIBILITY.
  1445 
  1446 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1447 
  1448 * Removed [split_format ... and ... and ...] version of
  1449 [split_format].  Potential INCOMPATIBILITY.
  1450 
  1451 * Predicate "sorted" now defined inductively, with nice induction
  1452 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1453 
  1454 * Constant "contents" renamed to "the_elem", to free the generic name
  1455 contents for other uses.  INCOMPATIBILITY.
  1456 
  1457 * Renamed class eq and constant eq (for code generation) to class
  1458 equal and constant equal, plus renaming of related facts and various
  1459 tuning.  INCOMPATIBILITY.
  1460 
  1461 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1462 
  1463 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1464 INCOMPATIBILITY.
  1465 
  1466 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1467 avoid confusion with finite sets.  INCOMPATIBILITY.
  1468 
  1469 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1470 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1471 for congruent(2)).
  1472 
  1473 * Some previously unqualified names have been qualified:
  1474 
  1475   types
  1476     bool ~> HOL.bool
  1477     nat ~> Nat.nat
  1478 
  1479   constants
  1480     Trueprop ~> HOL.Trueprop
  1481     True ~> HOL.True
  1482     False ~> HOL.False
  1483     op & ~> HOL.conj
  1484     op | ~> HOL.disj
  1485     op --> ~> HOL.implies
  1486     op = ~> HOL.eq
  1487     Not ~> HOL.Not
  1488     The ~> HOL.The
  1489     All ~> HOL.All
  1490     Ex ~> HOL.Ex
  1491     Ex1 ~> HOL.Ex1
  1492     Let ~> HOL.Let
  1493     If ~> HOL.If
  1494     Ball ~> Set.Ball
  1495     Bex ~> Set.Bex
  1496     Suc ~> Nat.Suc
  1497     Pair ~> Product_Type.Pair
  1498     fst ~> Product_Type.fst
  1499     snd ~> Product_Type.snd
  1500     curry ~> Product_Type.curry
  1501     op : ~> Set.member
  1502     Collect ~> Set.Collect
  1503 
  1504 INCOMPATIBILITY.
  1505 
  1506 * More canonical naming convention for some fundamental definitions:
  1507 
  1508     bot_bool_eq ~> bot_bool_def
  1509     top_bool_eq ~> top_bool_def
  1510     inf_bool_eq ~> inf_bool_def
  1511     sup_bool_eq ~> sup_bool_def
  1512     bot_fun_eq  ~> bot_fun_def
  1513     top_fun_eq  ~> top_fun_def
  1514     inf_fun_eq  ~> inf_fun_def
  1515     sup_fun_eq  ~> sup_fun_def
  1516 
  1517 INCOMPATIBILITY.
  1518 
  1519 * More stylized fact names:
  1520 
  1521   expand_fun_eq ~> fun_eq_iff
  1522   expand_set_eq ~> set_eq_iff
  1523   set_ext       ~> set_eqI
  1524   nat_number    ~> eval_nat_numeral
  1525 
  1526 INCOMPATIBILITY.
  1527 
  1528 * Refactoring of code-generation specific operations in theory List:
  1529 
  1530   constants
  1531     null ~> List.null
  1532 
  1533   facts
  1534     mem_iff ~> member_def
  1535     null_empty ~> null_def
  1536 
  1537 INCOMPATIBILITY.  Note that these were not supposed to be used
  1538 regularly unless for striking reasons; their main purpose was code
  1539 generation.
  1540 
  1541 Various operations from the Haskell prelude are used for generating
  1542 Haskell code.
  1543 
  1544 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1545 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1546 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1547 
  1548 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1549 "*" and "+" respectively.  INCOMPATIBILITY.
  1550 
  1551 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1552 "Sum_Type.Plus" instead.
  1553 
  1554 * Constant "split" has been merged with constant "prod_case"; names of
  1555 ML functions, facts etc. involving split have been retained so far,
  1556 though.  INCOMPATIBILITY.
  1557 
  1558 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1559 instead.  INCOMPATIBILITY.
  1560 
  1561 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1562 INCOMPATIBILITY.
  1563 
  1564 * Former theory Library/Enum is now part of the HOL-Main image.
  1565 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1566 referred to by its qualified name.
  1567 
  1568   enum    ~>  Enum.enum
  1569   nlists  ~>  Enum.nlists
  1570   product ~>  Enum.product
  1571 
  1572 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1573 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1574 INCOMPATIBILITY.
  1575 
  1576 * Theory Library/SetsAndFunctions has been split into
  1577 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1578 for instance definitions for functions; various improvements.
  1579 INCOMPATIBILITY.
  1580 
  1581 * Theory Library/Multiset provides stable quicksort implementation of
  1582 sort_key.
  1583 
  1584 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1585 INCOMPATIBILITY.
  1586 
  1587 * Session Multivariate_Analysis: introduced a type class for euclidean
  1588 space.  Most theorems are now stated in terms of euclidean spaces
  1589 instead of finite cartesian products.
  1590 
  1591   types
  1592     real ^ 'n ~>  'a::real_vector
  1593               ~>  'a::euclidean_space
  1594               ~>  'a::ordered_euclidean_space
  1595         (depends on your needs)
  1596 
  1597   constants
  1598      _ $ _        ~> _ $$ _
  1599      \<chi> x. _  ~> \<chi>\<chi> x. _
  1600      CARD('n)     ~> DIM('a)
  1601 
  1602 Also note that the indices are now natural numbers and not from some
  1603 finite type. Finite cartesian products of euclidean spaces, products
  1604 of euclidean spaces the real and complex numbers are instantiated to
  1605 be euclidean_spaces.  INCOMPATIBILITY.
  1606 
  1607 * Session Probability: introduced pextreal as positive extended real
  1608 numbers.  Use pextreal as value for measures.  Introduce the
  1609 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1610 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1611 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1612 
  1613 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1614 INCOMPATIBILITY.
  1615 
  1616 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1617 prove verification conditions generated by the SPARK Ada program
  1618 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1619 
  1620 
  1621 *** HOL-Algebra ***
  1622 
  1623 * Theorems for additive ring operations (locale abelian_monoid and
  1624 descendants) are generated by interpretation from their multiplicative
  1625 counterparts.  Names (in particular theorem names) have the mandatory
  1626 qualifier 'add'.  Previous theorem names are redeclared for
  1627 compatibility.
  1628 
  1629 * Structure "int_ring" is now an abbreviation (previously a
  1630 definition).  This fits more natural with advanced interpretations.
  1631 
  1632 
  1633 *** HOLCF ***
  1634 
  1635 * The domain package now runs in definitional mode by default: The
  1636 former command 'new_domain' is now called 'domain'.  To use the domain
  1637 package in its original axiomatic mode, use 'domain (unsafe)'.
  1638 INCOMPATIBILITY.
  1639 
  1640 * The new class "domain" is now the default sort.  Class "predomain"
  1641 is an unpointed version of "domain". Theories can be updated by
  1642 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1643 
  1644   'a::type ~> 'a::countable
  1645   'a::cpo  ~> 'a::predomain
  1646   'a::pcpo ~> 'a::domain
  1647 
  1648 * The old type class "rep" has been superseded by class "domain".
  1649 Accordingly, users of the definitional package must remove any
  1650 "default_sort rep" declarations.  INCOMPATIBILITY.
  1651 
  1652 * The domain package (definitional mode) now supports unpointed
  1653 predomain argument types, as long as they are marked 'lazy'. (Strict
  1654 arguments must be in class "domain".) For example, the following
  1655 domain definition now works:
  1656 
  1657   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1658 
  1659 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1660 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1661 'a option, and 'a list.  Additionally, it configures fixrec and the
  1662 domain package to work with these types.  For example:
  1663 
  1664   fixrec isInl :: "('a + 'b) u -> tr"
  1665     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1666 
  1667   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1668 
  1669 * The "(permissive)" option of fixrec has been replaced with a
  1670 per-equation "(unchecked)" option. See
  1671 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1672 
  1673 * The "bifinite" class no longer fixes a constant "approx"; the class
  1674 now just asserts that such a function exists.  INCOMPATIBILITY.
  1675 
  1676 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1677 defines an embedding of type 'a defl into udom by default; instances
  1678 of "bifinite" and "domain" classes are available in
  1679 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1680 
  1681 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1682 
  1683 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1684 
  1685 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1686 
  1687 * The function "cprod_map" has been renamed to "prod_map".
  1688 INCOMPATIBILITY.
  1689 
  1690 * The monadic bind operator on each powerdomain has new binder syntax
  1691 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1692 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1693 
  1694 * The infix syntax for binary union on each powerdomain has changed
  1695 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1696 syntax.  INCOMPATIBILITY.
  1697 
  1698 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1699 still supported as an input translation.
  1700 
  1701 * Renamed some theorems (the original names are also still available).
  1702 
  1703   expand_fun_below   ~> fun_below_iff
  1704   below_fun_ext      ~> fun_belowI
  1705   expand_cfun_eq     ~> cfun_eq_iff
  1706   ext_cfun           ~> cfun_eqI
  1707   expand_cfun_below  ~> cfun_below_iff
  1708   below_cfun_ext     ~> cfun_belowI
  1709   cont2cont_Rep_CFun ~> cont2cont_APP
  1710 
  1711 * The Abs and Rep functions for various types have changed names.
  1712 Related theorem names have also changed to match. INCOMPATIBILITY.
  1713 
  1714   Rep_CFun  ~> Rep_cfun
  1715   Abs_CFun  ~> Abs_cfun
  1716   Rep_Sprod ~> Rep_sprod
  1717   Abs_Sprod ~> Abs_sprod
  1718   Rep_Ssum  ~> Rep_ssum
  1719   Abs_Ssum  ~> Abs_ssum
  1720 
  1721 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1722 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1723 
  1724 * Various changes to bisimulation/coinduction with domain package:
  1725 
  1726   - Definitions of "bisim" constants no longer mention definedness.
  1727   - With mutual recursion, "bisim" predicate is now curried.
  1728   - With mutual recursion, each type gets a separate coind theorem.
  1729   - Variable names in bisim_def and coinduct rules have changed.
  1730 
  1731 INCOMPATIBILITY.
  1732 
  1733 * Case combinators generated by the domain package for type "foo" are
  1734 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1735 
  1736 * Several theorems have been renamed to more accurately reflect the
  1737 names of constants and types involved.  INCOMPATIBILITY.
  1738 
  1739   thelub_const    ~> lub_const
  1740   lub_const       ~> is_lub_const
  1741   thelubI         ~> lub_eqI
  1742   is_lub_lub      ~> is_lubD2
  1743   lubI            ~> is_lub_lub
  1744   unique_lub      ~> is_lub_unique
  1745   is_ub_lub       ~> is_lub_rangeD1
  1746   lub_bin_chain   ~> is_lub_bin_chain
  1747   lub_fun         ~> is_lub_fun
  1748   thelub_fun      ~> lub_fun
  1749   thelub_cfun     ~> lub_cfun
  1750   thelub_Pair     ~> lub_Pair
  1751   lub_cprod       ~> is_lub_prod
  1752   thelub_cprod    ~> lub_prod
  1753   minimal_cprod   ~> minimal_prod
  1754   inst_cprod_pcpo ~> inst_prod_pcpo
  1755   UU_I            ~> bottomI
  1756   compact_UU      ~> compact_bottom
  1757   deflation_UU    ~> deflation_bottom
  1758   finite_deflation_UU ~> finite_deflation_bottom
  1759 
  1760 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1761 
  1762   sq_ord_less_eq_trans ~> below_eq_trans
  1763   sq_ord_eq_less_trans ~> eq_below_trans
  1764   refl_less            ~> below_refl
  1765   trans_less           ~> below_trans
  1766   antisym_less         ~> below_antisym
  1767   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1768   box_less             ~> box_below
  1769   rev_trans_less       ~> rev_below_trans
  1770   not_less2not_eq      ~> not_below2not_eq
  1771   less_UU_iff          ~> below_UU_iff
  1772   flat_less_iff        ~> flat_below_iff
  1773   adm_less             ~> adm_below
  1774   adm_not_less         ~> adm_not_below
  1775   adm_compact_not_less ~> adm_compact_not_below
  1776   less_fun_def         ~> below_fun_def
  1777   expand_fun_less      ~> fun_below_iff
  1778   less_fun_ext         ~> fun_belowI
  1779   less_discr_def       ~> below_discr_def
  1780   discr_less_eq        ~> discr_below_eq
  1781   less_unit_def        ~> below_unit_def
  1782   less_cprod_def       ~> below_prod_def
  1783   prod_lessI           ~> prod_belowI
  1784   Pair_less_iff        ~> Pair_below_iff
  1785   fst_less_iff         ~> fst_below_iff
  1786   snd_less_iff         ~> snd_below_iff
  1787   expand_cfun_less     ~> cfun_below_iff
  1788   less_cfun_ext        ~> cfun_belowI
  1789   injection_less       ~> injection_below
  1790   less_up_def          ~> below_up_def
  1791   not_Iup_less         ~> not_Iup_below
  1792   Iup_less             ~> Iup_below
  1793   up_less              ~> up_below
  1794   Def_inject_less_eq   ~> Def_below_Def
  1795   Def_less_is_eq       ~> Def_below_iff
  1796   spair_less_iff       ~> spair_below_iff
  1797   less_sprod           ~> below_sprod
  1798   spair_less           ~> spair_below
  1799   sfst_less_iff        ~> sfst_below_iff
  1800   ssnd_less_iff        ~> ssnd_below_iff
  1801   fix_least_less       ~> fix_least_below
  1802   dist_less_one        ~> dist_below_one
  1803   less_ONE             ~> below_ONE
  1804   ONE_less_iff         ~> ONE_below_iff
  1805   less_sinlD           ~> below_sinlD
  1806   less_sinrD           ~> below_sinrD
  1807 
  1808 
  1809 *** FOL and ZF ***
  1810 
  1811 * All constant names are now qualified internally and use proper
  1812 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1813 
  1814 *** ZF ***
  1815 
  1816 * Greater support for structured proofs involving induction or case analysis.
  1817 
  1818 * Much greater use of special symbols.
  1819 
  1820 * Removal of many ML theorem bindings. INCOMPATIBILITY.
  1821 
  1822 *** ML ***
  1823 
  1824 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1825 Fail if the argument is false.  Due to inlining the source position of
  1826 failed assertions is included in the error output.
  1827 
  1828 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1829 text is in practice always evaluated with a stable theory checkpoint.
  1830 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1831 
  1832 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1833 the current context, not any accidental theory loader state as before.
  1834 Potential INCOMPATIBILITY, subtle change in semantics.
  1835 
  1836 * Syntax.pretty_priority (default 0) configures the required priority
  1837 of pretty-printed output and thus affects insertion of parentheses.
  1838 
  1839 * Syntax.default_root (default "any") configures the inner syntax
  1840 category (nonterminal symbol) for parsing of terms.
  1841 
  1842 * Former exception Library.UnequalLengths now coincides with
  1843 ListPair.UnequalLengths.
  1844 
  1845 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1846 main functionality is provided by structure Simplifier.
  1847 
  1848 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1849 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1850 almost all situations.
  1851 
  1852 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1853 See implementation manual for further details on exceptions in
  1854 Isabelle/ML.
  1855 
  1856 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1857 meaning.
  1858 
  1859 * Renamed structure PureThy to Pure_Thy and moved most of its
  1860 operations to structure Global_Theory, to emphasize that this is
  1861 rarely-used global-only stuff.
  1862 
  1863 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1864 instead (or tracing for high-volume output).
  1865 
  1866 * Configuration option show_question_marks only affects regular pretty
  1867 printing of types and terms, not raw Term.string_of_vname.
  1868 
  1869 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1870 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1871 @{thms} for most purposes.
  1872 
  1873 * ML structure Unsynchronized is never opened, not even in Isar
  1874 interaction mode as before.  Old Unsynchronized.set etc. have been
  1875 discontinued -- use plain := instead.  This should be *rare* anyway,
  1876 since modern tools always work via official context data, notably
  1877 configuration options.
  1878 
  1879 * Parallel and asynchronous execution requires special care concerning
  1880 interrupts.  Structure Exn provides some convenience functions that
  1881 avoid working directly with raw Interrupt.  User code must not absorb
  1882 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1883 followed by re-raising of the original exception.  Another common
  1884 source of mistakes are "handle _" patterns, which make the meaning of
  1885 the program subject to physical effects of the environment.
  1886 
  1887 
  1888 
  1889 New in Isabelle2009-2 (June 2010)
  1890 ---------------------------------
  1891 
  1892 *** General ***
  1893 
  1894 * Authentic syntax for *all* logical entities (type classes, type
  1895 constructors, term constants): provides simple and robust
  1896 correspondence between formal entities and concrete syntax.  Within
  1897 the parse tree / AST representations, "constants" are decorated by
  1898 their category (class, type, const) and spelled out explicitly with
  1899 their full internal name.
  1900 
  1901 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1902 and translations (translation rules and translation functions in ML).
  1903 Some hints on upgrading:
  1904 
  1905   - Many existing uses of 'syntax' and 'translations' can be replaced
  1906     by more modern 'type_notation', 'notation' and 'abbreviation',
  1907     which are independent of this issue.
  1908 
  1909   - 'translations' require markup within the AST; the term syntax
  1910     provides the following special forms:
  1911 
  1912       CONST c   -- produces syntax version of constant c from context
  1913       XCONST c  -- literally c, checked as constant from context
  1914       c         -- literally c, if declared by 'syntax'
  1915 
  1916     Plain identifiers are treated as AST variables -- occasionally the
  1917     system indicates accidental variables via the error "rhs contains
  1918     extra variables".
  1919 
  1920     Type classes and type constructors are marked according to their
  1921     concrete syntax.  Some old translations rules need to be written
  1922     for the "type" category, using type constructor application
  1923     instead of pseudo-term application of the default category
  1924     "logic".
  1925 
  1926   - 'parse_translation' etc. in ML may use the following
  1927     antiquotations:
  1928 
  1929       @{class_syntax c}   -- type class c within parse tree / AST
  1930       @{term_syntax c}    -- type constructor c within parse tree / AST
  1931       @{const_syntax c}   -- ML version of "CONST c" above
  1932       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1933 
  1934   - Literal types within 'typed_print_translations', i.e. those *not*
  1935     represented as pseudo-terms are represented verbatim.  Use @{class
  1936     c} or @{type_name c} here instead of the above syntax
  1937     antiquotations.
  1938 
  1939 Note that old non-authentic syntax was based on unqualified base
  1940 names, so all of the above "constant" names would coincide.  Recall
  1941 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1942 diagnose syntax problems.
  1943 
  1944 * Type constructors admit general mixfix syntax, not just infix.
  1945 
  1946 * Concrete syntax may be attached to local entities without a proof
  1947 body, too.  This works via regular mixfix annotations for 'fix',
  1948 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1949 similar to the 'notation' command in theory specifications.
  1950 
  1951 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1952 need to specify constant name and syntax separately.  Internal ML
  1953 datatype constructors have been renamed from InfixName to Infix etc.
  1954 Minor INCOMPATIBILITY.
  1955 
  1956 * Schematic theorem statements need to be explicitly markup as such,
  1957 via commands 'schematic_lemma', 'schematic_theorem',
  1958 'schematic_corollary'.  Thus the relevance of the proof is made
  1959 syntactically clear, which impacts performance in a parallel or
  1960 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1961 
  1962 * Use of cumulative prems via "!" in some proof methods has been
  1963 discontinued (old legacy feature).
  1964 
  1965 * References 'trace_simp' and 'debug_simp' have been replaced by
  1966 configuration options stored in the context. Enabling tracing (the
  1967 case of debugging is similar) in proofs works via
  1968 
  1969   using [[trace_simp = true]]
  1970 
  1971 Tracing is then active for all invocations of the simplifier in
  1972 subsequent goal refinement steps. Tracing may also still be enabled or
  1973 disabled via the ProofGeneral settings menu.
  1974 
  1975 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1976 'hide_fact' replace the former 'hide' KIND command.  Minor
  1977 INCOMPATIBILITY.
  1978 
  1979 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1980 more efficient than combinations with -q1 or -q2.
  1981 
  1982 
  1983 *** Pure ***
  1984 
  1985 * Proofterms record type-class reasoning explicitly, using the
  1986 "unconstrain" operation internally.  This eliminates all sort
  1987 constraints from a theorem and proof, introducing explicit
  1988 OFCLASS-premises.  On the proof term level, this operation is
  1989 automatically applied at theorem boundaries, such that closed proofs
  1990 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1991 inspect proof terms.
  1992 
  1993 * Local theory specifications may depend on extra type variables that
  1994 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1995 are added internally.  For example:
  1996 
  1997   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1998 
  1999 * Predicates of locales introduced by classes carry a mandatory
  2000 "class" prefix.  INCOMPATIBILITY.
  2001 
  2002 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  2003 
  2004 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  2005 'class' instead.
  2006 
  2007 * Command 'code_reflect' allows to incorporate generated ML code into
  2008 runtime environment; replaces immature code_datatype antiquotation.
  2009 INCOMPATIBILITY.
  2010 
  2011 * Code generator: simple concept for abstract datatypes obeying
  2012 invariants.
  2013 
  2014 * Code generator: details of internal data cache have no impact on the
  2015 user space functionality any longer.
  2016 
  2017 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  2018 subgoals.  This is more appropriate for interpretations with 'where'.
  2019 INCOMPATIBILITY.
  2020 
  2021 * Command 'example_proof' opens an empty proof body.  This allows to
  2022 experiment with Isar, without producing any persistent result.
  2023 
  2024 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  2025 within a local theory context, with explicit checking of the
  2026 constructors involved (in contrast to the raw 'syntax' versions).
  2027 
  2028 * Commands 'types' and 'typedecl' now work within a local theory
  2029 context -- without introducing dependencies on parameters or
  2030 assumptions, which is not possible in Isabelle/Pure.
  2031 
  2032 * Command 'defaultsort' has been renamed to 'default_sort', it works
  2033 within a local theory context.  Minor INCOMPATIBILITY.
  2034 
  2035 
  2036 *** HOL ***
  2037 
  2038 * Command 'typedef' now works within a local theory context -- without
  2039 introducing dependencies on parameters or assumptions, which is not
  2040 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  2041 contain multiple interpretations of local typedefs (with different
  2042 non-emptiness proofs), even in a global theory context.
  2043 
  2044 * New package for quotient types.  Commands 'quotient_type' and
  2045 'quotient_definition' may be used for defining types and constants by
  2046 quotient constructions.  An example is the type of integers created by
  2047 quotienting pairs of natural numbers:
  2048 
  2049   fun
  2050     intrel :: "(nat * nat) => (nat * nat) => bool"
  2051   where
  2052     "intrel (x, y) (u, v) = (x + v = u + y)"
  2053 
  2054   quotient_type int = "nat * nat" / intrel
  2055     by (auto simp add: equivp_def expand_fun_eq)
  2056 
  2057   quotient_definition
  2058     "0::int" is "(0::nat, 0::nat)"
  2059 
  2060 The method "lifting" can be used to lift of theorems from the
  2061 underlying "raw" type to the quotient type.  The example
  2062 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  2063 construction and provides a reasoning infrastructure for finite sets.
  2064 
  2065 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  2066 clash with new theory Quotient in Main HOL.
  2067 
  2068 * Moved the SMT binding into the main HOL session, eliminating
  2069 separate HOL-SMT session.
  2070 
  2071 * List membership infix mem operation is only an input abbreviation.
  2072 INCOMPATIBILITY.
  2073 
  2074 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  2075 for future developements; former Library/Word.thy is still present in
  2076 the AFP entry RSAPPS.
  2077 
  2078 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  2079 longer shadowed.  INCOMPATIBILITY.
  2080 
  2081 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  2082 INCOMPATIBILITY.
  2083 
  2084 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  2085 INCOMPATIBILITY.
  2086 
  2087 * Dropped normalizing_semiring etc; use the facts in semiring classes
  2088 instead.  INCOMPATIBILITY.
  2089 
  2090 * Dropped several real-specific versions of lemmas about floor and
  2091 ceiling; use the generic lemmas from theory "Archimedean_Field"
  2092 instead.  INCOMPATIBILITY.
  2093 
  2094   floor_number_of_eq         ~> floor_number_of
  2095   le_floor_eq_number_of      ~> number_of_le_floor
  2096   le_floor_eq_zero           ~> zero_le_floor
  2097   le_floor_eq_one            ~> one_le_floor
  2098   floor_less_eq_number_of    ~> floor_less_number_of
  2099   floor_less_eq_zero         ~> floor_less_zero
  2100   floor_less_eq_one          ~> floor_less_one
  2101   less_floor_eq_number_of    ~> number_of_less_floor
  2102   less_floor_eq_zero         ~> zero_less_floor
  2103   less_floor_eq_one          ~> one_less_floor
  2104   floor_le_eq_number_of      ~> floor_le_number_of
  2105   floor_le_eq_zero           ~> floor_le_zero
  2106   floor_le_eq_one            ~> floor_le_one
  2107   floor_subtract_number_of   ~> floor_diff_number_of
  2108   floor_subtract_one         ~> floor_diff_one
  2109   ceiling_number_of_eq       ~> ceiling_number_of
  2110   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  2111   ceiling_le_zero_eq         ~> ceiling_le_zero
  2112   ceiling_le_eq_one          ~> ceiling_le_one
  2113   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  2114   less_ceiling_eq_zero       ~> zero_less_ceiling
  2115   less_ceiling_eq_one        ~> one_less_ceiling
  2116   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  2117   ceiling_less_eq_zero       ~> ceiling_less_zero
  2118   ceiling_less_eq_one        ~> ceiling_less_one
  2119   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  2120   le_ceiling_eq_zero         ~> zero_le_ceiling
  2121   le_ceiling_eq_one          ~> one_le_ceiling
  2122   ceiling_subtract_number_of ~> ceiling_diff_number_of
  2123   ceiling_subtract_one       ~> ceiling_diff_one
  2124 
  2125 * Theory "Finite_Set": various folding_XXX locales facilitate the
  2126 application of the various fold combinators on finite sets.
  2127 
  2128 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  2129 provides abstract red-black tree type which is backed by "RBT_Impl" as
  2130 implementation.  INCOMPATIBILTY.
  2131 
  2132 * Theory Library/Coinductive_List has been removed -- superseded by
  2133 AFP/thys/Coinductive.
  2134 
  2135 * Theory PReal, including the type "preal" and related operations, has
  2136 been removed.  INCOMPATIBILITY.
  2137 
  2138 * Real: new development using Cauchy Sequences.
  2139 
  2140 * Split off theory "Big_Operators" containing setsum, setprod,
  2141 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  2142 
  2143 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  2144 "Int" etc.  INCOMPATIBILITY.
  2145 
  2146 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  2147 
  2148 * New set of rules "ac_simps" provides combined assoc / commute
  2149 rewrites for all interpretations of the appropriate generic locales.
  2150 
  2151 * Renamed theory "OrderedGroup" to "Groups" and split theory
  2152 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  2153 appropriate and more consistent names suitable for name prefixes
  2154 within the HOL theories.  INCOMPATIBILITY.
  2155 
  2156 * Some generic constants have been put to appropriate theories:
  2157   - less_eq, less: Orderings
  2158   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  2159   - inverse, divide: Rings
  2160 INCOMPATIBILITY.
  2161 
  2162 * More consistent naming of type classes involving orderings (and
  2163 lattices):
  2164 
  2165     lower_semilattice                   ~> semilattice_inf
  2166     upper_semilattice                   ~> semilattice_sup
  2167 
  2168     dense_linear_order                  ~> dense_linorder
  2169 
  2170     pordered_ab_group_add               ~> ordered_ab_group_add
  2171     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  2172     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  2173     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  2174     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  2175     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  2176     pordered_cancel_semiring            ~> ordered_cancel_semiring
  2177     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  2178     pordered_comm_ring                  ~> ordered_comm_ring
  2179     pordered_comm_semiring              ~> ordered_comm_semiring
  2180     pordered_ring                       ~> ordered_ring
  2181     pordered_ring_abs                   ~> ordered_ring_abs
  2182     pordered_semiring                   ~> ordered_semiring
  2183 
  2184     ordered_ab_group_add                ~> linordered_ab_group_add
  2185     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  2186     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  2187     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  2188     ordered_field                       ~> linordered_field
  2189     ordered_field_no_lb                 ~> linordered_field_no_lb
  2190     ordered_field_no_ub                 ~> linordered_field_no_ub
  2191     ordered_field_dense_linear_order    ~> dense_linordered_field
  2192     ordered_idom                        ~> linordered_idom
  2193     ordered_ring                        ~> linordered_ring
  2194     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  2195     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  2196     ordered_ring_strict                 ~> linordered_ring_strict
  2197     ordered_semidom                     ~> linordered_semidom
  2198     ordered_semiring                    ~> linordered_semiring
  2199     ordered_semiring_1                  ~> linordered_semiring_1
  2200     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  2201     ordered_semiring_strict             ~> linordered_semiring_strict
  2202 
  2203   The following slightly odd type classes have been moved to a
  2204   separate theory Library/Lattice_Algebras:
  2205 
  2206     lordered_ab_group_add               ~> lattice_ab_group_add
  2207     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  2208     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  2209     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  2210     lordered_ring                       ~> lattice_ring
  2211 
  2212 INCOMPATIBILITY.
  2213 
  2214 * Refined field classes:
  2215   - classes division_ring_inverse_zero, field_inverse_zero,
  2216     linordered_field_inverse_zero include rule inverse 0 = 0 --
  2217     subsumes former division_by_zero class;
  2218   - numerous lemmas have been ported from field to division_ring.
  2219 INCOMPATIBILITY.
  2220 
  2221 * Refined algebra theorem collections:
  2222   - dropped theorem group group_simps, use algebra_simps instead;
  2223   - dropped theorem group ring_simps, use field_simps instead;
  2224   - proper theorem collection field_simps subsumes former theorem
  2225     groups field_eq_simps and field_simps;
  2226   - dropped lemma eq_minus_self_iff which is a duplicate for
  2227     equal_neg_zero.
  2228 INCOMPATIBILITY.
  2229 
  2230 * Theory Finite_Set and List: some lemmas have been generalized from
  2231 sets to lattices:
  2232 
  2233   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  2234   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  2235   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  2236   union_Union_fold_union        ~> sup_Sup_fold_sup
  2237   Inter_fold_inter              ~> Inf_fold_inf
  2238   Union_fold_union              ~> Sup_fold_sup
  2239   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  2240   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  2241   INTER_fold_inter              ~> INFI_fold_inf
  2242   UNION_fold_union              ~> SUPR_fold_sup
  2243 
  2244 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  2245 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  2246 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  2247 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  2248 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  2249 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  2250 
  2251 * Reorganized theory Multiset: swapped notation of pointwise and
  2252 multiset order:
  2253 
  2254   - pointwise ordering is instance of class order with standard syntax
  2255     <= and <;
  2256   - multiset ordering has syntax <=# and <#; partial order properties
  2257     are provided by means of interpretation with prefix
  2258     multiset_order;
  2259   - less duplication, less historical organization of sections,
  2260     conversion from associations lists to multisets, rudimentary code
  2261     generation;
  2262   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  2263     if needed.
  2264 
  2265 Renamed:
  2266 
  2267   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  2268   multi_count_ext  ~>  multiset_ext
  2269   diff_union_inverse2  ~>  diff_union_cancelR
  2270 
  2271 INCOMPATIBILITY.
  2272 
  2273 * Theory Permutation: replaced local "remove" by List.remove1.
  2274 
  2275 * Code generation: ML and OCaml code is decorated with signatures.
  2276 
  2277 * Theory List: added transpose.
  2278 
  2279 * Library/Nat_Bijection.thy is a collection of bijective functions
  2280 between nat and other types, which supersedes the older libraries
  2281 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2282 
  2283   Constants:
  2284   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2285   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2286   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2287   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2288   Countable.pair_encode           ~> prod_encode
  2289   NatIso.prod2nat                 ~> prod_encode
  2290   NatIso.nat2prod                 ~> prod_decode
  2291   NatIso.sum2nat                  ~> sum_encode
  2292   NatIso.nat2sum                  ~> sum_decode
  2293   NatIso.list2nat                 ~> list_encode
  2294   NatIso.nat2list                 ~> list_decode
  2295   NatIso.set2nat                  ~> set_encode
  2296   NatIso.nat2set                  ~> set_decode
  2297 
  2298   Lemmas:
  2299   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2300   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2301   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2302   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2303   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2304   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2305   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2306   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2307   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2308   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2309   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2310   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2311   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2312 
  2313 * Sledgehammer:
  2314   - Renamed ATP commands:
  2315     atp_info     ~> sledgehammer running_atps
  2316     atp_kill     ~> sledgehammer kill_atps
  2317     atp_messages ~> sledgehammer messages
  2318     atp_minimize ~> sledgehammer minimize
  2319     print_atps   ~> sledgehammer available_atps
  2320     INCOMPATIBILITY.
  2321   - Added user's manual ("isabelle doc sledgehammer").
  2322   - Added option syntax and "sledgehammer_params" to customize
  2323     Sledgehammer's behavior.  See the manual for details.
  2324   - Modified the Isar proof reconstruction code so that it produces
  2325     direct proofs rather than proofs by contradiction.  (This feature
  2326     is still experimental.)
  2327   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2328     full-typed mode.
  2329   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2330 
  2331 * Nitpick:
  2332   - Added and implemented "binary_ints" and "bits" options.
  2333   - Added "std" option and implemented support for nonstandard models.
  2334   - Added and implemented "finitize" option to improve the precision
  2335     of infinite datatypes based on a monotonicity analysis.
  2336   - Added support for quotient types.
  2337   - Added support for "specification" and "ax_specification"
  2338     constructs.
  2339   - Added support for local definitions (for "function" and
  2340     "termination" proofs).
  2341   - Added support for term postprocessors.
  2342   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2343   - Improved efficiency of "destroy_constrs" optimization.
  2344   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2345     record getters.
  2346   - Fixed soundness bug related to higher-order constructors.
  2347   - Fixed soundness bug when "full_descrs" is enabled.
  2348   - Improved precision of set constructs.
  2349   - Added "atoms" option.
  2350   - Added cache to speed up repeated Kodkod invocations on the same
  2351     problems.
  2352   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2353     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2354     "SAT4J_Light".  INCOMPATIBILITY.
  2355   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2356     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2357   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2358 
  2359 * Method "induct" now takes instantiations of the form t, where t is not
  2360   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2361   If this is not intended, t has to be enclosed in parentheses.
  2362   By default, the equalities generated by definitional instantiations
  2363   are pre-simplified, which may cause parameters of inductive cases
  2364   to disappear, or may even delete some of the inductive cases.
  2365   Use "induct (no_simp)" instead of "induct" to restore the old
  2366   behaviour. The (no_simp) option is also understood by the "cases"
  2367   and "nominal_induct" methods, which now perform pre-simplification, too.
  2368   INCOMPATIBILITY.
  2369 
  2370 
  2371 *** HOLCF ***
  2372 
  2373 * Variable names in lemmas generated by the domain package have
  2374 changed; the naming scheme is now consistent with the HOL datatype
  2375 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2376 
  2377 * The domain package no longer defines the function "foo_copy" for
  2378 recursive domain "foo".  The reach lemma is now stated directly in
  2379 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2380 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2381 
  2382 * Most definedness lemmas generated by the domain package (previously
  2383 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2384 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2385 Proofs that used definedness lemmas as intro rules may break,
  2386 potential INCOMPATIBILITY.
  2387 
  2388 * Induction and casedist rules generated by the domain package now
  2389 declare proper case_names (one called "bottom", and one named for each
  2390 constructor).  INCOMPATIBILITY.
  2391 
  2392 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2393 rules are generated for each domain, INCOMPATIBILITY.
  2394 
  2395   foo_bar.reach       ~> foo.reach  bar.reach
  2396   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2397 
  2398 * Some lemmas generated by the domain package have been renamed for
  2399 consistency with the datatype package, INCOMPATIBILITY.
  2400 
  2401   foo.ind        ~> foo.induct
  2402   foo.finite_ind ~> foo.finite_induct
  2403   foo.coind      ~> foo.coinduct
  2404   foo.casedist   ~> foo.exhaust
  2405   foo.exhaust    ~> foo.nchotomy
  2406 
  2407 * For consistency with other definition packages, the fixrec package
  2408 now generates qualified theorem names, INCOMPATIBILITY.
  2409 
  2410   foo_simps  ~> foo.simps
  2411   foo_unfold ~> foo.unfold
  2412   foo_induct ~> foo.induct
  2413 
  2414 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2415 method and internal fixrec proofs now use the default simpset instead.
  2416 INCOMPATIBILITY.
  2417 
  2418 * The "contlub" predicate has been removed.  Proof scripts should use
  2419 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2420 
  2421 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2422 
  2423 * The constants cpair, cfst, and csnd have been removed in favor of
  2424 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2425 
  2426 
  2427 *** ML ***
  2428 
  2429 * Antiquotations for basic formal entities:
  2430 
  2431     @{class NAME}         -- type class
  2432     @{class_syntax NAME}  -- syntax representation of the above
  2433 
  2434     @{type_name NAME}     -- logical type
  2435     @{type_abbrev NAME}   -- type abbreviation
  2436     @{nonterminal NAME}   -- type of concrete syntactic category
  2437     @{type_syntax NAME}   -- syntax representation of any of the above
  2438 
  2439     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2440     @{const_abbrev NAME}  -- abbreviated constant
  2441     @{const_syntax NAME}  -- syntax representation of any of the above
  2442 
  2443 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2444 syntax constant (cf. 'syntax' command).
  2445 
  2446 * Antiquotation @{make_string} inlines a function to print arbitrary
  2447 values similar to the ML toplevel.  The result is compiler dependent
  2448 and may fall back on "?" in certain situations.
  2449 
  2450 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2451 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2452 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2453 not work with the asynchronous Isar document model.
  2454 
  2455 * Configuration options now admit dynamic default values, depending on
  2456 the context or even global references.
  2457 
  2458 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2459 uses an efficient external library if available (for Poly/ML).
  2460 
  2461 * Renamed some important ML structures, while keeping the old names
  2462 for some time as aliases within the structure Legacy:
  2463 
  2464   OuterKeyword  ~>  Keyword
  2465   OuterLex      ~>  Token
  2466   OuterParse    ~>  Parse
  2467   OuterSyntax   ~>  Outer_Syntax
  2468   PrintMode     ~>  Print_Mode
  2469   SpecParse     ~>  Parse_Spec
  2470   ThyInfo       ~>  Thy_Info
  2471   ThyLoad       ~>  Thy_Load
  2472   ThyOutput     ~>  Thy_Output
  2473   TypeInfer     ~>  Type_Infer
  2474 
  2475 Note that "open Legacy" simplifies porting of sources, but forgetting
  2476 to remove it again will complicate porting again in the future.
  2477 
  2478 * Most operations that refer to a global context are named
  2479 accordingly, e.g. Simplifier.global_context or
  2480 ProofContext.init_global.  There are some situations where a global
  2481 context actually works, but under normal circumstances one needs to
  2482 pass the proper local context through the code!
  2483 
  2484 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2485 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2486 Pretty.pp argument to merge, which is absent in the standard
  2487 Theory_Data version.
  2488 
  2489 * Sorts.certify_sort and derived "cert" operations for types and terms
  2490 no longer minimize sorts.  Thus certification at the boundary of the
  2491 inference kernel becomes invariant under addition of class relations,
  2492 which is an important monotonicity principle.  Sorts are now minimized
  2493 in the syntax layer only, at the boundary between the end-user and the
  2494 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2495 explicitly in rare situations.
  2496 
  2497 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2498 emphasize that this is in no way a standard operation.
  2499 INCOMPATIBILITY.
  2500 
  2501 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2502 usual for resolution.  Rare INCOMPATIBILITY.
  2503 
  2504 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2505 to emphasize that these only work in a global situation (which is
  2506 quite rare).
  2507 
  2508 * Curried take and drop in library.ML; negative length is interpreted
  2509 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2510 
  2511 * Proof terms: type substitutions on proof constants now use canonical
  2512 order of type variables.  INCOMPATIBILITY for tools working with proof
  2513 terms.
  2514 
  2515 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2516 may no longer carry premises.  User-level specifications are
  2517 transformed accordingly by Thm.add_axiom/add_def.
  2518 
  2519 
  2520 *** System ***
  2521 
  2522 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2523 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2524 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2525 
  2526 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2527 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2528 respectively.
  2529 
  2530 * Old lib/scripts/polyml-platform is superseded by the
  2531 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2532 variant, even on a 64 bit machine.  The following example setting
  2533 prefers 64 bit if available:
  2534 
  2535   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2536 
  2537 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2538 Isabelle/Scala layer for advanced prover interaction and integration.
  2539 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2540 component.
  2541 
  2542 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2543 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2544 similar to the default assignment of the document preparation system
  2545 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2546 provides some operations for direct access to the font without asking
  2547 the user for manual installation.
  2548 
  2549 
  2550 
  2551 New in Isabelle2009-1 (December 2009)
  2552 -------------------------------------
  2553 
  2554 *** General ***
  2555 
  2556 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2557 one backslash should be used, even in ML sources.
  2558 
  2559 
  2560 *** Pure ***
  2561 
  2562 * Locale interpretation propagates mixins along the locale hierarchy.
  2563 The currently only available mixins are the equations used to map
  2564 local definitions to terms of the target domain of an interpretation.
  2565 
  2566 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2567 loc" to print all interpretations of locale "loc" in the theory.
  2568 Interpretations in proofs are not shown.
  2569 
  2570 * Thoroughly revised locales tutorial.  New section on conditional
  2571 interpretation.
  2572 
  2573 * On instantiation of classes, remaining undefined class parameters
  2574 are formally declared.  INCOMPATIBILITY.
  2575 
  2576 
  2577 *** Document preparation ***
  2578 
  2579 * New generalized style concept for printing terms: @{foo (style) ...}
  2580 instead of @{foo_style style ...}  (old form is still retained for
  2581 backward compatibility).  Styles can be also applied for
  2582 antiquotations prop, term_type and typeof.
  2583 
  2584 
  2585 *** HOL ***
  2586 
  2587 * New proof method "smt" for a combination of first-order logic with
  2588 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2589 fixed-size bitvectors; there is also basic support for higher-order
  2590 features (esp. lambda abstractions).  It is an incomplete decision
  2591 procedure based on external SMT solvers using the oracle mechanism;
  2592 for the SMT solver Z3, this method is proof-producing.  Certificates
  2593 are provided to avoid calling the external solvers solely for
  2594 re-checking proofs.  Due to a remote SMT service there is no need for
  2595 installing SMT solvers locally.  See src/HOL/SMT.
  2596 
  2597 * New commands to load and prove verification conditions generated by
  2598 the Boogie program verifier or derived systems (e.g. the Verifying C
  2599 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2600 
  2601 * New counterexample generator tool 'nitpick' based on the Kodkod
  2602 relational model finder.  See src/HOL/Tools/Nitpick and
  2603 src/HOL/Nitpick_Examples.
  2604 
  2605 * New commands 'code_pred' and 'values' to invoke the predicate
  2606 compiler and to enumerate values of inductive predicates.
  2607 
  2608 * A tabled implementation of the reflexive transitive closure.
  2609 
  2610 * New implementation of quickcheck uses generic code generator;
  2611 default generators are provided for all suitable HOL types, records
  2612 and datatypes.  Old quickcheck can be re-activated importing theory
  2613 Library/SML_Quickcheck.
  2614 
  2615 * New testing tool Mirabelle for automated proof tools.  Applies
  2616 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2617 every proof step in a theory.  To be used in batch mode via the
  2618 "mirabelle" utility.
  2619 
  2620 * New proof method "sos" (sum of squares) for nonlinear real
  2621 arithmetic (originally due to John Harison). It requires theory
  2622 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2623 works well in practice on quantifier-free real arithmetic with +, -,
  2624 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2625 inequalities between polynomials.  It makes use of external
  2626 semidefinite programming solvers.  Method "sos" generates a
  2627 certificate that can be pasted into the proof thus avoiding the need
  2628 to call an external tool every time the proof is checked.  See
  2629 src/HOL/Library/Sum_Of_Squares.
  2630 
  2631 * New method "linarith" invokes existing linear arithmetic decision
  2632 procedure only.
  2633 
  2634 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2635 
  2636 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2637 Causes full type information to be output to the ATPs.  This slows
  2638 ATPs down considerably but eliminates a source of unsound "proofs"
  2639 that fail later.
  2640 
  2641 * New method "metisFT": A version of metis that uses full type
  2642 information in order to avoid failures of proof reconstruction.
  2643 
  2644 * New evaluator "approximate" approximates an real valued term using
  2645 the same method as the approximation method.
  2646 
  2647 * Method "approximate" now supports arithmetic expressions as
  2648 boundaries of intervals and implements interval splitting and Taylor
  2649 series expansion.
  2650 
  2651 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2652 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2653 
  2654 * New theory SupInf of the supremum and infimum operators for sets of
  2655 reals.
  2656 
  2657 * New theory Probability, which contains a development of measure
  2658 theory, eventually leading to Lebesgue integration and probability.
  2659 
  2660 * Extended Multivariate Analysis to include derivation and Brouwer's
  2661 fixpoint theorem.
  2662 
  2663 * Reorganization of number theory, INCOMPATIBILITY:
  2664   - new number theory development for nat and int, in theories Divides
  2665     and GCD as well as in new session Number_Theory
  2666   - some constants and facts now suffixed with _nat and _int
  2667     accordingly
  2668   - former session NumberTheory now named Old_Number_Theory, including
  2669     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2670   - moved theory Pocklington from src/HOL/Library to
  2671     src/HOL/Old_Number_Theory
  2672 
  2673 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2674 lcm of finite and infinite sets. It is shown that they form a complete
  2675 lattice.
  2676 
  2677 * Class semiring_div requires superclass no_zero_divisors and proof of
  2678 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2679 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2680 generalized to class semiring_div, subsuming former theorems
  2681 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2682 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2683 INCOMPATIBILITY.
  2684 
  2685 * Refinements to lattice classes and sets:
  2686   - less default intro/elim rules in locale variant, more default
  2687     intro/elim rules in class variant: more uniformity
  2688   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2689     le_inf_iff
  2690   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2691     sup_aci)
  2692   - renamed ACI to inf_sup_aci
  2693   - new class "boolean_algebra"
  2694   - class "complete_lattice" moved to separate theory
  2695     "Complete_Lattice"; corresponding constants (and abbreviations)
  2696     renamed and with authentic syntax:
  2697     Set.Inf ~>    Complete_Lattice.Inf
  2698     Set.Sup ~>    Complete_Lattice.Sup
  2699     Set.INFI ~>   Complete_Lattice.INFI
  2700     Set.SUPR ~>   Complete_Lattice.SUPR
  2701     Set.Inter ~>  Complete_Lattice.Inter
  2702     Set.Union ~>  Complete_Lattice.Union
  2703     Set.INTER ~>  Complete_Lattice.INTER
  2704     Set.UNION ~>  Complete_Lattice.UNION
  2705   - authentic syntax for
  2706     Set.Pow
  2707     Set.image
  2708   - mere abbreviations:
  2709     Set.empty               (for bot)
  2710     Set.UNIV                (for top)
  2711     Set.inter               (for inf, formerly Set.Int)
  2712     Set.union               (for sup, formerly Set.Un)
  2713     Complete_Lattice.Inter  (for Inf)
  2714     Complete_Lattice.Union  (for Sup)
  2715     Complete_Lattice.INTER  (for INFI)
  2716     Complete_Lattice.UNION  (for SUPR)
  2717   - object-logic definitions as far as appropriate
  2718 
  2719 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2720 Un_subset_iff are explicitly deleted as default simp rules; then also
  2721 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2722 deleted to achieve the desired effect.
  2723 
  2724 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2725 rules by default any longer; the same applies to min_max.inf_absorb1
  2726 etc.  INCOMPATIBILITY.
  2727 
  2728 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2729 pred_set_conv by default.  INCOMPATIBILITY.
  2730 
  2731 * Power operations on relations and functions are now one dedicated
  2732 constant "compow" with infix syntax "^^".  Power operation on
  2733 multiplicative monoids retains syntax "^" and is now defined generic
  2734 in class power.  INCOMPATIBILITY.
  2735 
  2736 * Relation composition "R O S" now has a more standard argument order:
  2737 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2738 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2739 break, since the O_assoc rule was not rewritten like this.  Fix using
  2740 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2741 
  2742 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2743 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2744 INCOMPATIBILITY.
  2745 
  2746 * Most rules produced by inductive and datatype package have mandatory
  2747 prefixes.  INCOMPATIBILITY.
  2748 
  2749 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2750 the attribute of the same name.  Each of the theorems in the list
  2751 DERIV_intros assumes composition with an additional function and
  2752 matches a variable to the derivative, which has to be solved by the
  2753 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2754 of most elementary terms.  Former Maclauren.DERIV_tac and
  2755 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2756 INCOMPATIBILITY.
  2757 
  2758 * Code generator attributes follow the usual underscore convention:
  2759     code_unfold     replaces    code unfold
  2760     code_post       replaces    code post
  2761     etc.
  2762   INCOMPATIBILITY.
  2763 
  2764 * Renamed methods:
  2765     sizechange -> size_change
  2766     induct_scheme -> induction_schema
  2767   INCOMPATIBILITY.
  2768 
  2769 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2770 INCOMPATIBILITY, use "undefined" directly.
  2771 
  2772 * Renamed theorems:
  2773     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2774     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2775     Suc_plus1 -> Suc_eq_plus1
  2776     *anti_sym -> *antisym*
  2777     vector_less_eq_def -> vector_le_def
  2778   INCOMPATIBILITY.
  2779 
  2780 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2781 INCOMPATIBILITY.
  2782 
  2783 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2784 INCOMPATIBILITY.
  2785 
  2786 
  2787 *** HOLCF ***
  2788 
  2789 * Theory Representable defines a class "rep" of domains that are
  2790 representable (via an ep-pair) in the universal domain type "udom".
  2791 Instances are provided for all type constructors defined in HOLCF.
  2792 
  2793 * The 'new_domain' command is a purely definitional version of the
  2794 domain package, for representable domains.  Syntax is identical to the
  2795 old domain package.  The 'new_domain' package also supports indirect
  2796 recursion using previously-defined type constructors.  See
  2797 src/HOLCF/ex/New_Domain.thy for examples.
  2798 
  2799 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2800 on the left-hand side of an equation, and then performs
  2801 simplification.  Rewriting is done using rules declared with the
  2802 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2803 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2804 
  2805 * The pattern-match compiler in 'fixrec' can now handle constructors
  2806 with HOL function types.  Pattern-match combinators for the Pair
  2807 constructor are pre-configured.
  2808 
  2809 * The 'fixrec' package now produces better fixed-point induction rules
  2810 for mutually-recursive definitions:  Induction rules have conclusions
  2811 of the form "P foo bar" instead of "P <foo, bar>".
  2812 
  2813 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2814 been renamed to "below".  The name "below" now replaces "less" in many
  2815 theorem names.  (Legacy theorem names using "less" are still supported
  2816 as well.)
  2817 
  2818 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2819 patterns can be used to generate strictness rules, or to make
  2820 functions more strict (much like the bang-patterns supported by the
  2821 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2822 examples.
  2823 
  2824 
  2825 *** ML ***
  2826 
  2827 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2828 errors and run-time exceptions, including detailed source positions.
  2829 
  2830 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2831 identified entries, with some additional information such as source
  2832 position, logical grouping etc.
  2833 
  2834 * Theory and context data is now introduced by the simplified and
  2835 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2836 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2837 copy operation) is still available for some time.
  2838 
  2839 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2840 provides a high-level programming interface to synchronized state
  2841 variables with atomic update.  This works via pure function
  2842 application within a critical section -- its runtime should be as
  2843 short as possible; beware of deadlocks if critical code is nested,
  2844 either directly or indirectly via other synchronized variables!
  2845 
  2846 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2847 wraps raw ML references, explicitly indicating their non-thread-safe
  2848 behaviour.  The Isar toplevel keeps this structure open, to
  2849 accommodate Proof General as well as quick and dirty interactive
  2850 experiments with references.
  2851 
  2852 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2853 parallel tactical reasoning.
  2854 
  2855 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2856 are similar to SUBPROOF, but are slightly more flexible: only the
  2857 specified parts of the subgoal are imported into the context, and the
  2858 body tactic may introduce new subgoals and schematic variables.
  2859 
  2860 * Old tactical METAHYPS, which does not observe the proof context, has
  2861 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2862 or Subgoal.FOCUS etc.
  2863 
  2864 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2865 functors have their own ML name space there is no point to mark them
  2866 separately.)  Minor INCOMPATIBILITY.
  2867 
  2868 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2869 
  2870 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2871 INCOMPATIBILITY.
  2872 
  2873 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2874 mode, which avoids critical setmp.
  2875 
  2876 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2877 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2878 Attrib/Method.setup introduced in Isabelle2009.
  2879 
  2880 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2881 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2882 last resort.  INCOMPATIBILITY.
  2883 
  2884 * Display.pretty_thm now requires a proper context (cf. former
  2885 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2886 or even Display.pretty_thm_without_context as last resort.
  2887 INCOMPATIBILITY.
  2888 
  2889 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2890 Syntax.pretty_typ/term directly, preferably with proper context
  2891 instead of global theory.
  2892 
  2893 
  2894 *** System ***
  2895 
  2896 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2897 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2898 usedir option -q.
  2899 
  2900 * Support for additional "Isabelle components" via etc/components, see
  2901 also the system manual.
  2902 
  2903 * The isabelle makeall tool now operates on all components with
  2904 IsaMakefile, not just hardwired "logics".
  2905 
  2906 * Removed "compress" option from isabelle-process and isabelle usedir;
  2907 this is always enabled.
  2908 
  2909 * Discontinued support for Poly/ML 4.x versions.
  2910 
  2911 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2912 on a given logic image.  This requires the lighttpd webserver and is
  2913 currently supported on Linux only.
  2914 
  2915 
  2916 
  2917 New in Isabelle2009 (April 2009)
  2918 --------------------------------
  2919 
  2920 *** General ***
  2921 
  2922 * Simplified main Isabelle executables, with less surprises on
  2923 case-insensitive file-systems (such as Mac OS).
  2924 
  2925   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2926     "isatool."
  2927 
  2928   - The former "isabelle" alias for "isabelle-process" has been
  2929     removed (should rarely occur to regular users).
  2930 
  2931   - The former "isabelle-interface" and its alias "Isabelle" have been
  2932     removed (interfaces are now regular Isabelle tools).
  2933 
  2934 Within scripts and make files, the Isabelle environment variables
  2935 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2936 respectively.  (The latter are still available as legacy feature.)
  2937 
  2938 The old isabelle-interface wrapper could react in confusing ways if
  2939 the interface was uninstalled or changed otherwise.  Individual
  2940 interface tool configuration is now more explicit, see also the
  2941 Isabelle system manual.  In particular, Proof General is now available
  2942 via "isabelle emacs".
  2943 
  2944 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2945 purge installed copies of Isabelle executables and re-run "isabelle
  2946 install -p ...", or use symlinks.
  2947 
  2948 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2949 old ~/isabelle, which was slightly non-standard and apt to cause
  2950 surprises on case-insensitive file-systems (such as Mac OS).
  2951 
  2952 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2953 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2954 care is required when using older releases of Isabelle.  Note that
  2955 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2956 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2957 
  2958 * Proofs of fully specified statements are run in parallel on
  2959 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2960 a regular 4-core machine, if the initial heap space is made reasonably
  2961 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2962 
  2963 * The main reference manuals ("isar-ref", "implementation", and
  2964 "system") have been updated and extended.  Formally checked references
  2965 as hyperlinks are now available uniformly.
  2966 
  2967 
  2968 *** Pure ***
  2969 
  2970 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2971 respects.  The most important changes are listed below.  See the
  2972 Tutorial on Locales ("locales" manual) for details.
  2973 
  2974 - In locale expressions, instantiation replaces renaming.  Parameters
  2975 must be declared in a for clause.  To aid compatibility with previous
  2976 parameter inheritance, in locale declarations, parameters that are not
  2977 'touched' (instantiation position "_" or omitted) are implicitly added
  2978 with their syntax at the beginning of the for clause.
  2979 
  2980 - Syntax from abbreviations and definitions in locales is available in
  2981 locale expressions and context elements.  The latter is particularly
  2982 useful in locale declarations.
  2983 
  2984 - More flexible mechanisms to qualify names generated by locale
  2985 expressions.  Qualifiers (prefixes) may be specified in locale
  2986 expressions, and can be marked as mandatory (syntax: "name!:") or
  2987 optional (syntax "name?:").  The default depends for plain "name:"
  2988 depends on the situation where a locale expression is used: in
  2989 commands 'locale' and 'sublocale' prefixes are optional, in
  2990 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2991 implicit qualifiers derived from the parameter names of a locale are
  2992 no longer generated.
  2993 
  2994 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2995 instantiation clause in "interpretation" and "interpret" (square
  2996 brackets) is no longer available.  Use locale expressions.
  2997 
  2998 - When converting proof scripts, mandatory qualifiers in
  2999 'interpretation' and 'interpret' should be retained by default, even
  3000 if this is an INCOMPATIBILITY compared to former behavior.  In the
  3001 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  3002 in locale expressions range over a single locale instance only.
  3003 
  3004 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  3005 In existing theorem specifications replace the includes element by the
  3006 respective context elements of the included locale, omitting those
  3007 that are already present in the theorem specification.  Multiple
  3008 assume elements of a locale should be replaced by a single one
  3009 involving the locale predicate.  In the proof body, declarations (most
  3010 notably theorems) may be regained by interpreting the respective
  3011 locales in the proof context as required (command "interpret").
  3012 
  3013 If using "includes" in replacement of a target solely because the
  3014 parameter types in the theorem are not as general as in the target,
  3015 consider declaring a new locale with additional type constraints on
  3016 the parameters (context element "constrains").
  3017 
  3018 - Discontinued "locale (open)".  INCOMPATIBILITY.
  3019 
  3020 - Locale interpretation commands no longer attempt to simplify goal.
  3021 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  3022 methods intro_locales and unfold_locales to clarify.
  3023 
  3024 - Locale interpretation commands no longer accept interpretation
  3025 attributes.  INCOMPATIBILITY.
  3026 
  3027 * Class declaration: so-called "base sort" must not be given in import
  3028 list any longer, but is inferred from the specification.  Particularly
  3029 in HOL, write
  3030 
  3031     class foo = ...
  3032 
  3033 instead of
  3034 
  3035     class foo = type + ...
  3036 
  3037 * Class target: global versions of theorems stemming do not carry a
  3038 parameter prefix any longer.  INCOMPATIBILITY.
  3039 
  3040 * Class 'instance' command no longer accepts attached definitions.
  3041 INCOMPATIBILITY, use proper 'instantiation' target instead.
  3042 
  3043 * Recovered hiding of consts, which was accidentally broken in
  3044 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  3045 makes c inaccessible; consider using ``hide (open) const c'' instead.
  3046 
  3047 * Slightly more coherent Pure syntax, with updated documentation in
  3048 isar-ref manual.  Removed locales meta_term_syntax and
  3049 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  3050 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  3051 directly in regular applications.
  3052 
  3053 * There is a new syntactic category "float_const" for signed decimal
  3054 fractions (e.g. 123.45 or -123.45).
  3055 
  3056 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  3057 interface with 'setup' command instead.
  3058 
  3059 * Command 'local_setup' is similar to 'setup', but operates on a local
  3060 theory context.
  3061 
  3062 * The 'axiomatization' command now only works within a global theory
  3063 context.  INCOMPATIBILITY.
  3064 
  3065 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  3066 hypotheses.  Sorts required in the course of reasoning need to be
  3067 covered by the constraints in the initial statement, completed by the
  3068 type instance information of the background theory.  Non-trivial sort
  3069 hypotheses, which rarely occur in practice, may be specified via
  3070 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  3071 
  3072   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  3073 
  3074 The result contains an implicit sort hypotheses as before --
  3075 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  3076 normalization.
  3077 
  3078 * Generalized Isar history, with support for linear undo, direct state
  3079 addressing etc.
  3080 
  3081 * Changed defaults for unify configuration options:
  3082 
  3083   unify_trace_bound = 50 (formerly 25)
  3084   unify_search_bound = 60 (formerly 30)
  3085 
  3086 * Different bookkeeping for code equations (INCOMPATIBILITY):
  3087 
  3088   a) On theory merge, the last set of code equations for a particular
  3089      constant is taken (in accordance with the policy applied by other
  3090      parts of the code generator framework).
  3091 
  3092   b) Code equations stemming from explicit declarations (e.g. code
  3093      attribute) gain priority over default code equations stemming
  3094      from definition, primrec, fun etc.
  3095 
  3096 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  3097 
  3098 * Unified theorem tables for both code generators.  Thus [code
  3099 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  3100 
  3101 * Command 'find_consts' searches for constants based on type and name
  3102 patterns, e.g.
  3103 
  3104     find_consts "_ => bool"
  3105 
  3106 By default, matching is against subtypes, but it may be restricted to
  3107 the whole type.  Searching by name is possible.  Multiple queries are
  3108 conjunctive and queries may be negated by prefixing them with a
  3109 hyphen:
  3110 
  3111     find_consts strict: "_ => bool" name: "Int" -"int => int"
  3112 
  3113 * New 'find_theorems' criterion "solves" matches theorems that
  3114 directly solve the current goal (modulo higher-order unification).
  3115 
  3116 * Auto solve feature for main theorem statements: whenever a new goal
  3117 is stated, "find_theorems solves" is called; any theorems that could
  3118 solve the lemma directly are listed as part of the goal state.
  3119 Cf. associated options in Proof General Isabelle settings menu,
  3120 enabled by default, with reasonable timeout for pathological cases of
  3121 higher-order unification.
  3122 
  3123 
  3124 *** Document preparation ***
  3125 
  3126 * Antiquotation @{lemma} now imitates a regular terminal proof,
  3127 demanding keyword 'by' and supporting the full method expression
  3128 syntax just like the Isar command 'by'.
  3129 
  3130 
  3131 *** HOL ***
  3132 
  3133 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  3134 points Main and Complex_Main remain as before.
  3135 
  3136 * Logic image HOL-Plain provides a minimal HOL with the most important
  3137 tools available (inductive, datatype, primrec, ...).  This facilitates
  3138 experimentation and tool development.  Note that user applications
  3139 (and library theories) should never refer to anything below theory
  3140 Main, as before.
  3141 
  3142 * Logic image HOL-Main stops at theory Main, and thus facilitates
  3143 experimentation due to shorter build times.
  3144 
  3145 * Logic image HOL-NSA contains theories of nonstandard analysis which
  3146 were previously part of former HOL-Complex.  Entry point Hyperreal
  3147 remains valid, but theories formerly using Complex_Main should now use
  3148 new entry point Hypercomplex.
  3149 
  3150 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  3151 Posix processes.  Avoids potentially expensive forking of the ML
  3152 process.  New thread-based implementation also works on non-Unix
  3153 platforms (Cygwin).  Provers are no longer hardwired, but defined
  3154 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  3155 commands are covered in the isar-ref manual.
  3156 
  3157 * Wrapper scripts for remote SystemOnTPTP service allows to use
  3158 sledgehammer without local ATP installation (Vampire etc.). Other
  3159 provers may be included via suitable ML wrappers, see also
  3160 src/HOL/ATP_Linkup.thy.
  3161 
  3162 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  3163 menu.
  3164 
  3165 * The metis method no longer fails because the theorem is too trivial
  3166 (contains the empty clause).
  3167 
  3168 * The metis method now fails in the usual manner, rather than raising
  3169 an exception, if it determines that it cannot prove the theorem.
  3170 
  3171 * Method "coherent" implements a prover for coherent logic (see also
  3172 src/Tools/coherent.ML).
  3173 
  3174 * Constants "undefined" and "default" replace "arbitrary".  Usually
  3175 "undefined" is the right choice to replace "arbitrary", though
  3176 logically there is no difference.  INCOMPATIBILITY.
  3177 
  3178 * Command "value" now integrates different evaluation mechanisms.  The
  3179 result of the first successful evaluation mechanism is printed.  In
  3180 square brackets a particular named evaluation mechanisms may be
  3181 specified (currently, [SML], [code] or [nbe]).  See further
  3182 src/HOL/ex/Eval_Examples.thy.
  3183 
  3184 * Normalization by evaluation now allows non-leftlinear equations.
  3185 Declare with attribute [code nbe].
  3186 
  3187 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  3188 as the structured Isar versions "cases" and "induct", cf. the
  3189 corresponding "cases" and "induct" attributes.  Mutual induction rules
  3190 are now presented as a list of individual projections
  3191 (e.g. foo_bar.inducts for types foo and bar); the old format with
  3192 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  3193 rare situations a different rule is selected --- notably nested tuple
  3194 elimination instead of former prod.exhaust: use explicit (case_tac t
  3195 rule: prod.exhaust) here.
  3196 
  3197 * Attributes "cases", "induct", "coinduct" support "del" option.
  3198 
  3199 * Removed fact "case_split_thm", which duplicates "case_split".
  3200 
  3201 * The option datatype has been moved to a new theory Option.  Renamed
  3202 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  3203 
  3204 * New predicate "strict_mono" classifies strict functions on partial
  3205 orders.  With strict functions on linear orders, reasoning about
  3206 (in)equalities is facilitated by theorems "strict_mono_eq",
  3207 "strict_mono_less_eq" and "strict_mono_less".
  3208 
  3209 * Some set operations are now proper qualified constants with
  3210 authentic syntax.  INCOMPATIBILITY:
  3211 
  3212     op Int ~>   Set.Int
  3213     op Un ~>    Set.Un
  3214     INTER ~>    Set.INTER
  3215     UNION ~>    Set.UNION
  3216     Inter ~>    Set.Inter
  3217     Union ~>    Set.Union
  3218     {} ~>       Set.empty
  3219     UNIV ~>     Set.UNIV
  3220 
  3221 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  3222 theory Set.
  3223 
  3224 * Auxiliary class "itself" has disappeared -- classes without any
  3225 parameter are treated as expected by the 'class' command.
  3226 
  3227 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  3228 
  3229 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  3230 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  3231 
  3232 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  3233 method "approximation".  It proves formulas on real values by using
  3234 interval arithmetic.  In the formulas are also the transcendental
  3235 functions sin, cos, tan, atan, ln, exp and the constant pi are
  3236 allowed. For examples see
  3237 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  3238 
  3239 * Theory "Reflection" now resides in HOL/Library.
  3240 
  3241 * Entry point to Word library now simply named "Word".
  3242 INCOMPATIBILITY.
  3243 
  3244 * Made source layout more coherent with logical distribution
  3245 structure:
  3246 
  3247     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  3248     src/HOL/Library/Code_Message.thy ~> src/HOL/
  3249     src/HOL/Library/GCD.thy ~> src/HOL/
  3250     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  3251     src/HOL/Library/Parity.thy ~> src/HOL/
  3252     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  3253     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  3254     src/HOL/Real/Lubs.thy ~> src/HOL/
  3255     src/HOL/Real/PReal.thy ~> src/HOL/
  3256     src/HOL/Real/Rational.thy ~> src/HOL/
  3257     src/HOL/Real/RComplete.thy ~> src/HOL/
  3258     src/HOL/Real/RealDef.thy ~> src/HOL/
  3259     src/HOL/Real/RealPow.thy ~> src/HOL/
  3260     src/HOL/Real/Real.thy ~> src/HOL/
  3261     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  3262     src/HOL/Complex/Complex.thy ~> src/HOL/
  3263     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  3264     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  3265     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  3266     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  3267     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  3268     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  3269     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  3270     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  3271     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  3272     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  3273     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  3274     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  3275     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  3276     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  3277     src/HOL/Real/Float ~> src/HOL/Library/
  3278     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  3279     src/HOL/Real/RealVector.thy ~> src/HOL/
  3280 
  3281     src/HOL/arith_data.ML ~> src/HOL/Tools
  3282     src/HOL/hologic.ML ~> src/HOL/Tools
  3283     src/HOL/simpdata.ML ~> src/HOL/Tools
  3284     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3285     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3286     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3287     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3288     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3289     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3290     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3291 
  3292     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3293     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3294     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3295     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3296     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3297     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3298 
  3299 * If methods "eval" and "evaluation" encounter a structured proof
  3300 state with !!/==>, only the conclusion is evaluated to True (if
  3301 possible), avoiding strange error messages.
  3302 
  3303 * Method "sizechange" automates termination proofs using (a
  3304 modification of) the size-change principle.  Requires SAT solver.  See
  3305 src/HOL/ex/Termination.thy for examples.
  3306 
  3307 * Simplifier: simproc for let expressions now unfolds if bound
  3308 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3309 
  3310 * Method "arith": Linear arithmetic now ignores all inequalities when
  3311 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3312 
  3313 * New attribute "arith" for facts that should always be used
  3314 automatically by arithmetic. It is intended to be used locally in
  3315 proofs, e.g.
  3316 
  3317   assumes [arith]: "x > 0"
  3318 
  3319 Global usage is discouraged because of possible performance impact.
  3320 
  3321 * New classes "top" and "bot" with corresponding operations "top" and
  3322 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3323 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3324 
  3325 * Changed definition lemma "less_fun_def" in order to provide an
  3326 instance for preorders on functions; use lemma "less_le" instead.
  3327 INCOMPATIBILITY.
  3328 
  3329 * Theory Orderings: class "wellorder" moved here, with explicit
  3330 induction rule "less_induct" as assumption.  For instantiation of
  3331 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3332 INCOMPATIBILITY.
  3333 
  3334 * Theory Orderings: added class "preorder" as superclass of "order".
  3335 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3336 etc. slightly changed.  Some theorems named order_class.* now named
  3337 preorder_class.*.
  3338 
  3339 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3340 "diag" to "Id_on".
  3341 
  3342 * Theory Finite_Set: added a new fold combinator of type
  3343 
  3344   ('a => 'b => 'b) => 'b => 'a set => 'b
  3345 
  3346 Occasionally this is more convenient than the old fold combinator
  3347 which is now defined in terms of the new one and renamed to
  3348 fold_image.
  3349 
  3350 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3351 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3352 extended with further lemmas!).  At the moment both still exist but
  3353 the former will disappear at some point.
  3354 
  3355 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3356 class recpower.  Type-specific simp rules for various recpower types
  3357 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3358 
  3359 rat_power_0    -> power_0
  3360 rat_power_Suc  -> power_Suc
  3361 realpow_0      -> power_0
  3362 realpow_Suc    -> power_Suc
  3363 complexpow_0   -> power_0
  3364 complexpow_Suc -> power_Suc
  3365 power_poly_0   -> power_0
  3366 power_poly_Suc -> power_Suc
  3367 
  3368 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3369 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3370 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3371 of lemmas from Divides has been generalized from nat to class
  3372 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3373 renames resulting from duplicate elimination:
  3374 
  3375     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3376     zero_dvd_iff ~>         dvd_0_left_iff
  3377     dvd_0 ~>                dvd_0_right
  3378     DIVISION_BY_ZERO_DIV ~> div_by_0
  3379     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3380     mult_div ~>             div_mult_self2_is_id
  3381     mult_mod ~>             mod_mult_self2_is_0
  3382 
  3383 * Theory IntDiv: removed many lemmas that are instances of class-based
  3384 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3385 rename old lemmas as follows:
  3386 
  3387 dvd_diff               -> nat_dvd_diff
  3388 dvd_zminus_iff         -> dvd_minus_iff
  3389 mod_add1_eq            -> mod_add_eq
  3390 mod_mult1_eq           -> mod_mult_right_eq
  3391 mod_mult1_eq'          -> mod_mult_left_eq
  3392 mod_mult_distrib_mod   -> mod_mult_eq
  3393 nat_mod_add_left_eq    -> mod_add_left_eq
  3394 nat_mod_add_right_eq   -> mod_add_right_eq
  3395 nat_mod_div_trivial    -> mod_div_trivial
  3396 nat_mod_mod_trivial    -> mod_mod_trivial
  3397 zdiv_zadd_self1        -> div_add_self1
  3398 zdiv_zadd_self2        -> div_add_self2
  3399 zdiv_zmult_self1       -> div_mult_self2_is_id
  3400 zdiv_zmult_self2       -> div_mult_self1_is_id
  3401 zdvd_triv_left         -> dvd_triv_left
  3402 zdvd_triv_right        -> dvd_triv_right
  3403 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3404 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3405 zmod_zadd_left_eq      -> mod_add_left_eq
  3406 zmod_zadd_right_eq     -> mod_add_right_eq
  3407 zmod_zadd_self1        -> mod_add_self1
  3408 zmod_zadd_self2        -> mod_add_self2
  3409 zmod_zadd1_eq          -> mod_add_eq
  3410 zmod_zdiff1_eq         -> mod_diff_eq
  3411 zmod_zdvd_zmod         -> mod_mod_cancel
  3412 zmod_zmod_cancel       -> mod_mod_cancel
  3413 zmod_zmult_self1       -> mod_mult_self2_is_0
  3414 zmod_zmult_self2       -> mod_mult_self1_is_0
  3415 zmod_1                 -> mod_by_1
  3416 zdiv_1                 -> div_by_1
  3417 zdvd_abs1              -> abs_dvd_iff
  3418 zdvd_abs2              -> dvd_abs_iff
  3419 zdvd_refl              -> dvd_refl
  3420 zdvd_trans             -> dvd_trans
  3421 zdvd_zadd              -> dvd_add
  3422 zdvd_zdiff             -> dvd_diff
  3423 zdvd_zminus_iff        -> dvd_minus_iff
  3424 zdvd_zminus2_iff       -> minus_dvd_iff
  3425 zdvd_zmultD            -> dvd_mult_right
  3426 zdvd_zmultD2           -> dvd_mult_left
  3427 zdvd_zmult_mono        -> mult_dvd_mono
  3428 zdvd_0_right           -> dvd_0_right
  3429 zdvd_0_left            -> dvd_0_left_iff
  3430 zdvd_1_left            -> one_dvd
  3431 zminus_dvd_iff         -> minus_dvd_iff
  3432 
  3433 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3434 
  3435 * The real numbers offer decimal input syntax: 12.34 is translated
  3436 into 1234/10^2. This translation is not reversed upon output.
  3437 
  3438 * Theory Library/Polynomial defines an abstract type 'a poly of
  3439 univariate polynomials with coefficients of type 'a.  In addition to
  3440 the standard ring operations, it also supports div and mod.  Code
  3441 generation is also supported, using list-style constructors.
  3442 
  3443 * Theory Library/Inner_Product defines a class of real_inner for real
  3444 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3445 => real.  Class real_inner is a subclass of real_normed_vector from
  3446 theory RealVector.
  3447 
  3448 * Theory Library/Product_Vector provides instances for the product
  3449 type 'a * 'b of several classes from RealVector and Inner_Product.
  3450 Definitions of addition, subtraction, scalar multiplication, norms,
  3451 and inner products are included.
  3452 
  3453 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3454 addition to the field operations, numerals and case syntax are also
  3455 supported.
  3456 
  3457 * Theory Library/Diagonalize provides constructive version of Cantor's
  3458 first diagonalization argument.
  3459 
  3460 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3461 zlcm (for int); carried together from various gcd/lcm developements in
  3462 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3463 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3464 may recover tupled syntax as follows:
  3465 
  3466     hide (open) const gcd
  3467     abbreviation gcd where
  3468       "gcd == (%(a, b). GCD.gcd a b)"
  3469     notation (output)
  3470       GCD.gcd ("gcd '(_, _')")
  3471 
  3472 The same works for lcm, zgcd, zlcm.
  3473 
  3474 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3475 instantiations for algebraic structures.  Removed some duplicate
  3476 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3477 
  3478 * ML antiquotation @{code} takes a constant as argument and generates
  3479 corresponding code in background and inserts name of the corresponding
  3480 resulting ML value/function/datatype constructor binding in place.
  3481 All occurrences of @{code} with a single ML block are generated
  3482 simultaneously.  Provides a generic and safe interface for
  3483 instrumentalizing code generation.  See
  3484 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3485 In future you ought to refrain from ad-hoc compiling generated SML
  3486 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3487 cannot refer to constants for which user-defined serializations are
  3488 set.  Refer to the corresponding ML counterpart directly in that
  3489 cases.
  3490 
  3491 * Command 'rep_datatype': instead of theorem names the command now
  3492 takes a list of terms denoting the constructors of the type to be
  3493 represented as datatype.  The characteristic theorems have to be
  3494 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3495 have disappeared in favour of existing ones:
  3496 
  3497     unit_induct                 ~> unit.induct
  3498     prod_induct                 ~> prod.induct
  3499     sum_induct                  ~> sum.induct
  3500     Suc_Suc_eq                  ~> nat.inject
  3501     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3502 
  3503 
  3504 *** HOL-Algebra ***
  3505 
  3506 * New locales for orders and lattices where the equivalence relation
  3507 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3508 locales use a record structure with field eq for the equivalence.
  3509 
  3510 * New theory of factorial domains.
  3511 
  3512 * Units_l_inv and Units_r_inv are now simp rules by default.
  3513 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3514 and/or r_inv will now also require deletion of these lemmas.
  3515 
  3516 * Renamed the following theorems, INCOMPATIBILITY:
  3517 
  3518 UpperD ~> Upper_memD
  3519 LowerD ~> Lower_memD
  3520 least_carrier ~> least_closed
  3521 greatest_carrier ~> greatest_closed
  3522 greatest_Lower_above ~> greatest_Lower_below
  3523 one_zero ~> carrier_one_zero
  3524 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3525 
  3526 
  3527 *** HOL-Nominal ***
  3528 
  3529 * Nominal datatypes can now contain type-variables.
  3530 
  3531 * Commands 'nominal_inductive' and 'equivariance' work with local
  3532 theory targets.
  3533 
  3534 * Nominal primrec can now works with local theory targets and its
  3535 specification syntax now conforms to the general format as seen in
  3536 'inductive' etc.
  3537 
  3538 * Method "perm_simp" honours the standard simplifier attributes
  3539 (no_asm), (no_asm_use) etc.
  3540 
  3541 * The new predicate #* is defined like freshness, except that on the
  3542 left hand side can be a set or list of atoms.
  3543 
  3544 * Experimental command 'nominal_inductive2' derives strong induction
  3545 principles for inductive definitions.  In contrast to
  3546 'nominal_inductive', which can only deal with a fixed number of
  3547 binders, it can deal with arbitrary expressions standing for sets of
  3548 atoms to be avoided.  The only inductive definition we have at the
  3549 moment that needs this generalisation is the typing rule for Lets in
  3550 the algorithm W:
  3551 
  3552  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3553  -----------------------------------------------------------------
  3554          Gamma |- Let x be t1 in t2 : T2
  3555 
  3556 In this rule one wants to avoid all the binders that are introduced by
  3557 "close Gamma T1".  We are looking for other examples where this
  3558 feature might be useful.  Please let us know.
  3559 
  3560 
  3561 *** HOLCF ***
  3562 
  3563 * Reimplemented the simplification procedure for proving continuity
  3564 subgoals.  The new simproc is extensible; users can declare additional
  3565 continuity introduction rules with the attribute [cont2cont].
  3566 
  3567 * The continuity simproc now uses a different introduction rule for
  3568 solving continuity subgoals on terms with lambda abstractions.  In
  3569 some rare cases the new simproc may fail to solve subgoals that the
  3570 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3571 Potential INCOMPATIBILITY.
  3572 
  3573 * Command 'fixrec': specification syntax now conforms to the general
  3574 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3575 examples.  INCOMPATIBILITY.
  3576 
  3577 
  3578 *** ZF ***
  3579 
  3580 * Proof of Zorn's Lemma for partial orders.
  3581 
  3582 
  3583 *** ML ***
  3584 
  3585 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3586 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3587 depends on multithreading, so timouts will not work before Poly/ML
  3588 5.2.1!
  3589 
  3590 * High-level support for concurrent ML programming, see
  3591 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3592 particularly convenient to organize independent functional
  3593 computations.  The concept of "synchronized variables" provides a
  3594 higher-order interface for components with shared state, avoiding the
  3595 delicate details of mutexes and condition variables.  (Requires
  3596 Poly/ML 5.2.1 or later.)
  3597 
  3598 * ML bindings produced via Isar commands are stored within the Isar
  3599 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3600 become thread-safe and work with undo as expected (concerning
  3601 top-level bindings, not side-effects on global references).
  3602 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3603 compiler at runtime; really global bindings need to be given outside a
  3604 theory.  (Requires Poly/ML 5.2 or later.)
  3605 
  3606 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3607 context.  Top-level ML bindings are stored within the proof context in
  3608 a purely sequential fashion, disregarding the nested proof structure.
  3609 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3610 proof.  (Requires Poly/ML 5.2 or later.)
  3611 
  3612 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3613 and Method.setup, as well as Isar commands 'attribute_setup' and
  3614 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3615 existing code accordingly, or use plain 'setup' together with old
  3616 Method.add_method.
  3617 
  3618 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3619 to 'a -> thm, while results are always tagged with an authentic oracle
  3620 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3621 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3622 accordingly.  Note that extra performance may be gained by producing
  3623 the cterm carefully, avoiding slow Thm.cterm_of.
  3624 
  3625 * Simplified interface for defining document antiquotations via
  3626 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3627 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3628 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3629 examples.
  3630 
  3631 * More systematic treatment of long names, abstract name bindings, and
  3632 name space operations.  Basic operations on qualified names have been
  3633 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3634 Long_Name.append.  Old type bstring has been mostly replaced by
  3635 abstract type binding (see structure Binding), which supports precise
  3636 qualification by packages and local theory targets, as well as proper
  3637 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3638 bstring values into Binding.name, or better pass through abstract
  3639 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3640 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3641 
  3642 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3643 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3644 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3645 
  3646 * Disposed old type and term read functions (Sign.read_def_typ,
  3647 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3648 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3649 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3650 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3651 resort for legacy applications.
  3652 
  3653 * Disposed old declarations, tactics, tactic combinators that refer to
  3654 the simpset or claset of an implicit theory (such as Addsimps,
  3655 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3656 embedded ML text, or local_simpset_of with a proper context passed as
  3657 explicit runtime argument.
  3658 
  3659 * Rules and tactics that read instantiations (read_instantiate,
  3660 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3661 context, which is required for parsing and type-checking.  Moreover,
  3662 the variables are specified as plain indexnames, not string encodings
  3663 thereof.  INCOMPATIBILITY.
  3664 
  3665 * Generic Toplevel.add_hook interface allows to analyze the result of
  3666 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3667 for theorem dependency output of transactions resulting in a new
  3668 theory state.
  3669 
  3670 * ML antiquotations: block-structured compilation context indicated by
  3671 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3672 
  3673   @{binding name}                         - basic name binding
  3674   @{let ?pat = term}                      - term abbreviation (HO matching)
  3675   @{note name = fact}                     - fact abbreviation
  3676   @{thm fact}                             - singleton fact (with attributes)
  3677   @{thms fact}                            - general fact (with attributes)
  3678   @{lemma prop by method}                 - singleton goal
  3679   @{lemma prop by meth1 meth2}            - singleton goal
  3680   @{lemma prop1 ... propN by method}      - general goal
  3681   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3682   @{lemma (open) ...}                     - open derivation
  3683 
  3684 
  3685 *** System ***
  3686 
  3687 * The Isabelle "emacs" tool provides a specific interface to invoke
  3688 Proof General / Emacs, with more explicit failure if that is not
  3689 installed (the old isabelle-interface script silently falls back on
  3690 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3691 installation location of the Proof General distribution.
  3692 
  3693 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3694 the Isabelle process into a JVM/Scala application.  See
  3695 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3696 process wrapper has been discontinued.)
  3697 
  3698 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3699 
  3700 * Various status messages (with exact source position information) are
  3701 emitted, if proper markup print mode is enabled.  This allows
  3702 user-interface components to provide detailed feedback on internal
  3703 prover operations.
  3704 
  3705 
  3706 
  3707 New in Isabelle2008 (June 2008)
  3708 -------------------------------
  3709 
  3710 *** General ***
  3711 
  3712 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3713 and updated, with formally checked references as hyperlinks.
  3714 
  3715 * Theory loader: use_thy (and similar operations) no longer set the
  3716 implicit ML context, which was occasionally hard to predict and in
  3717 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3718 provides a proper context already.
  3719 
  3720 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3721 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3722 'use' within a theory file will do the job.
  3723 
  3724 * Name space merge now observes canonical order, i.e. the second space
  3725 is inserted into the first one, while existing entries in the first
  3726 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3727 swap theory imports.
  3728 
  3729 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3730 INCOMPATIBILITY in identifier syntax etc.
  3731 
  3732 * Outer syntax: string tokens no longer admit escaped white space,
  3733 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3734 white space without escapes.
  3735 
  3736 * Outer syntax: string tokens may contain arbitrary character codes
  3737 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3738 "foo_bar".
  3739 
  3740 
  3741 *** Pure ***
  3742 
  3743 * Context-dependent token translations.  Default setup reverts locally
  3744 fixed variables, and adds hilite markup for undeclared frees.
  3745 
  3746 * Unused theorems can be found using the new command 'unused_thms'.
  3747 There are three ways of invoking it:
  3748 
  3749 (1) unused_thms
  3750      Only finds unused theorems in the current theory.
  3751 
  3752 (2) unused_thms thy_1 ... thy_n -
  3753      Finds unused theorems in the current theory and all of its ancestors,
  3754      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3755 
  3756 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3757      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3758      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3759      their ancestors.
  3760 
  3761 In order to increase the readability of the list produced by
  3762 unused_thms, theorems that have been created by a particular instance
  3763 of a theory command such as 'inductive' or 'function' are considered
  3764 to belong to the same "group", meaning that if at least one theorem in
  3765 this group is used, the other theorems in the same group are no longer
  3766 reported as unused.  Moreover, if all theorems in the group are
  3767 unused, only one theorem in the group is displayed.
  3768 
  3769 Note that proof objects have to be switched on in order for
  3770 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3771 usually the case when using Proof General with the default settings).
  3772 
  3773 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3774 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3775 duplicate fact bindings, or even accidental fact duplications.  Note
  3776 that tools may maintain dynamically scoped facts systematically, using
  3777 PureThy.add_thms_dynamic.
  3778 
  3779 * Command 'hide' now allows to hide from "fact" name space as well.
  3780 
  3781 * Eliminated destructive theorem database, simpset, claset, and
  3782 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3783 update of theories within ML code.
  3784 
  3785 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3786 INCOMPATIBILITY, object-logics depending on former Pure require
  3787 additional setup PureThy.old_appl_syntax_setup; object-logics
  3788 depending on former CPure need to refer to Pure.
  3789 
  3790 * Commands 'use' and 'ML' are now purely functional, operating on
  3791 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3792 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3793 INCOMPATIBILITY.
  3794 
  3795 * Command 'setup': discontinued implicit version with ML reference.
  3796 
  3797 * Instantiation target allows for simultaneous specification of class
  3798 instance operations together with an instantiation proof.
  3799 Type-checking phase allows to refer to class operations uniformly.
  3800 See src/HOL/Complex/Complex.thy for an Isar example and
  3801 src/HOL/Library/Eval.thy for an ML example.
  3802 
  3803 * Indexing of literal facts: be more serious about including only
  3804 facts from the visible specification/proof context, but not the
  3805 background context (locale etc.).  Affects `prop` notation and method
  3806 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3807 situations.
  3808 
  3809 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3810 "(open)" option, which used to expose internal bound variables to the
  3811 proof text.
  3812 
  3813 * Isar statements: removed obsolete case "rule_context".
  3814 INCOMPATIBILITY, better use explicit fixes/assumes.
  3815 
  3816 * Locale proofs: default proof step now includes 'unfold_locales';
  3817 hence 'proof' without argument may be used to unfold locale
  3818 predicates.
  3819 
  3820 
  3821 *** Document preparation ***
  3822 
  3823 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3824 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3825 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3826 spot); renamed link color from "darkblue" to "linkcolor" (default
  3827 value unchanged, can be redefined via \definecolor); no longer sets
  3828 "a4paper" option (unnecessary or even intrusive).
  3829 
  3830 * Antiquotation @{lemma A method} proves proposition A by the given
  3831 method (either a method name or a method name plus (optional) method
  3832 arguments in parentheses) and prints A just like @{prop A}.
  3833 
  3834 
  3835 *** HOL ***
  3836 
  3837 * New primrec package.  Specification syntax conforms in style to
  3838 definition/function/....  No separate induction rule is provided.  The
  3839 "primrec" command distinguishes old-style and new-style specifications
  3840 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3841 When adjusting theories, beware: constants stemming from new-style
  3842 primrec specifications have authentic syntax.
  3843 
  3844 * Metis prover is now an order of magnitude faster, and also works
  3845 with multithreading.
  3846 
  3847 * Metis: the maximum number of clauses that can be produced from a
  3848 theorem is now given by the attribute max_clauses.  Theorems that
  3849 exceed this number are ignored, with a warning printed.
  3850 
  3851 * Sledgehammer no longer produces structured proofs by default. To
  3852 enable, declare [[sledgehammer_full = true]].  Attributes
  3853 reconstruction_modulus, reconstruction_sorts renamed
  3854 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3855 
  3856 * Method "induct_scheme" derives user-specified induction rules
  3857 from well-founded induction and completeness of patterns. This factors
  3858 out some operations that are done internally by the function package
  3859 and makes them available separately.  See
  3860 src/HOL/ex/Induction_Scheme.thy for examples.
  3861 
  3862 * More flexible generation of measure functions for termination
  3863 proofs: Measure functions can be declared by proving a rule of the
  3864 form "is_measure f" and giving it the [measure_function] attribute.
  3865 The "is_measure" predicate is logically meaningless (always true), and
  3866 just guides the heuristic.  To find suitable measure functions, the
  3867 termination prover sets up the goal "is_measure ?f" of the appropriate
  3868 type and generates all solutions by prolog-style backwards proof using
  3869 the declared rules.
  3870 
  3871 This setup also deals with rules like 
  3872 
  3873   "is_measure f ==> is_measure (list_size f)"
  3874 
  3875 which accommodates nested datatypes that recurse through lists.
  3876 Similar rules are predeclared for products and option types.
  3877 
  3878 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3879 
  3880   INCOMPATIBILITIES:
  3881 
  3882   - Definitions of overloaded constants on sets have to be replaced by
  3883     definitions on => and bool.
  3884 
  3885   - Some definitions of overloaded operators on sets can now be proved
  3886     using the definitions of the operators on => and bool.  Therefore,
  3887     the following theorems have been renamed:
  3888 
  3889       subset_def   -> subset_eq
  3890       psubset_def  -> psubset_eq
  3891       set_diff_def -> set_diff_eq
  3892       Compl_def    -> Compl_eq
  3893       Sup_set_def  -> Sup_set_eq
  3894       Inf_set_def  -> Inf_set_eq
  3895       sup_set_def  -> sup_set_eq
  3896       inf_set_def  -> inf_set_eq
  3897 
  3898   - Due to the incompleteness of the HO unification algorithm, some
  3899     rules such as subst may require manual instantiation, if some of
  3900     the unknowns in the rule is a set.
  3901 
  3902   - Higher order unification and forward proofs:
  3903     The proof pattern
  3904 
  3905       have "P (S::'a set)" <...>
  3906       then have "EX S. P S" ..
  3907 
  3908     no longer works (due to the incompleteness of the HO unification
  3909     algorithm) and must be replaced by the pattern
  3910 
  3911       have "EX S. P S"
  3912       proof
  3913         show "P S" <...>
  3914       qed
  3915 
  3916   - Calculational reasoning with subst (or similar rules):
  3917     The proof pattern
  3918 
  3919       have "P (S::'a set)" <...>
  3920       also have "S = T" <...>
  3921       finally have "P T" .
  3922 
  3923     no longer works (for similar reasons as the previous example) and
  3924     must be replaced by something like
  3925 
  3926       have "P (S::'a set)" <...>
  3927       moreover have "S = T" <...>
  3928       ultimately have "P T" by simp
  3929 
  3930   - Tactics or packages written in ML code:
  3931     Code performing pattern matching on types via
  3932 
  3933       Type ("set", [T]) => ...
  3934 
  3935     must be rewritten. Moreover, functions like strip_type or
  3936     binder_types no longer return the right value when applied to a
  3937     type of the form
  3938 
  3939       T1 => ... => Tn => U => bool
  3940 
  3941     rather than
  3942 
  3943       T1 => ... => Tn => U set
  3944 
  3945 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3946 Wellfounded_Relations to theory Wellfounded.
  3947 
  3948 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3949 
  3950 * Class finite no longer treats UNIV as class parameter.  Use class
  3951 enum from theory Library/Enum instead to achieve a similar effect.
  3952 INCOMPATIBILITY.
  3953 
  3954 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3955 and "Cons".  INCOMPATIBILITY.
  3956 
  3957 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3958 Potential INCOMPATIBILITY.
  3959 
  3960 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3961 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3962 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3963 
  3964 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3965 the same name in theory Orderings:
  3966 
  3967   less_trans
  3968   less_linear
  3969   le_imp_less_or_eq
  3970   le_less_trans
  3971   less_le_trans
  3972   less_not_sym
  3973   less_asym
  3974 
  3975 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3976 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3977 and different variable names.
  3978 
  3979 * Library/Option_ord.thy: Canonical order on option type.
  3980 
  3981 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3982 finite maps.
  3983 
  3984 * Library/Countable.thy: Type class for countable types.
  3985 
  3986 * Theory Int: The representation of numerals has changed.  The infix
  3987 operator BIT and the bit datatype with constructors B0 and B1 have
  3988 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3989 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3990 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3991 accordingly.
  3992 
  3993 * Theory Nat: definition of <= and < on natural numbers no longer
  3994 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3995 le_def and less_def have disappeared.  Consider lemmas not_less
  3996 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3997 
  3998 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3999 (whose purpose mainly is for various fold_set functionals) have been
  4000 abandoned in favor of the existing algebraic classes
  4001 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  4002 lower_semilattice (resp. upper_semilattice) and linorder.
  4003 INCOMPATIBILITY.
  4004 
  4005 * Theory Transitive_Closure: induct and cases rules now declare proper
  4006 case_names ("base" and "step").  INCOMPATIBILITY.
  4007 
  4008 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  4009 lattices.  The form set-specific version is available as
  4010 Inductive.lfp_ordinal_induct_set.
  4011 
  4012 * Renamed theorems "power.simps" to "power_int.simps".
  4013 INCOMPATIBILITY.
  4014 
  4015 * Class semiring_div provides basic abstract properties of semirings
  4016 with division and modulo operations.  Subsumes former class dvd_mod.
  4017 
  4018 * Merged theories IntDef, Numeral and IntArith into unified theory
  4019 Int.  INCOMPATIBILITY.
  4020 
  4021 * Theory Library/Code_Index: type "index" now represents natural
  4022 numbers rather than integers.  INCOMPATIBILITY.
  4023 
  4024 * New class "uminus" with operation "uminus" (split of from class
  4025 "minus" which now only has operation "minus", binary).
  4026 INCOMPATIBILITY.
  4027 
  4028 * Constants "card", "internal_split", "option_map" now with authentic
  4029 syntax.  INCOMPATIBILITY.
  4030 
  4031 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  4032 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  4033 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  4034 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  4035 Sup_set_def, le_def, less_def, option_map_def now with object
  4036 equality.  INCOMPATIBILITY.
  4037 
  4038 * Records. Removed K_record, and replaced it by pure lambda term
  4039 %x. c. The simplifier setup is now more robust against eta expansion.
  4040 INCOMPATIBILITY: in cases explicitly referring to K_record.
  4041 
  4042 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  4043 
  4044 * Library/ListVector: new theory of arithmetic vector operations.
  4045 
  4046 * Library/Order_Relation: new theory of various orderings as sets of
  4047 pairs.  Defines preorders, partial orders, linear orders and
  4048 well-orders on sets and on types.
  4049 
  4050 
  4051 *** ZF ***
  4052 
  4053 * Renamed some theories to allow to loading both ZF and HOL in the
  4054 same session:
  4055 
  4056   Datatype  -> Datatype_ZF
  4057   Inductive -> Inductive_ZF
  4058   Int       -> Int_ZF
  4059   IntDiv    -> IntDiv_ZF
  4060   Nat       -> Nat_ZF
  4061   List      -> List_ZF
  4062   Main      -> Main_ZF
  4063 
  4064 INCOMPATIBILITY: ZF theories that import individual theories below
  4065 Main might need to be adapted.  Regular theory Main is still
  4066 available, as trivial extension of Main_ZF.
  4067 
  4068 
  4069 *** ML ***
  4070 
  4071 * ML within Isar: antiquotation @{const name} or @{const
  4072 name(typargs)} produces statically-checked Const term.
  4073 
  4074 * Functor NamedThmsFun: data is available to the user as dynamic fact
  4075 (of the same name).  Removed obsolete print command.
  4076 
  4077 * Removed obsolete "use_legacy_bindings" function.
  4078 
  4079 * The ``print mode'' is now a thread-local value derived from a global
  4080 template (the former print_mode reference), thus access becomes
  4081 non-critical.  The global print_mode reference is for session
  4082 management only; user-code should use print_mode_value,
  4083 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  4084 
  4085 * Functions system/system_out provide a robust way to invoke external
  4086 shell commands, with propagation of interrupts (requires Poly/ML
  4087 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  4088 
  4089 
  4090 *** System ***
  4091 
  4092 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  4093 in accordance with Proof General 3.7, which prefers GNU emacs.
  4094 
  4095 * isatool tty runs Isabelle process with plain tty interaction;
  4096 optional line editor may be specified via ISABELLE_LINE_EDITOR
  4097 setting, the default settings attempt to locate "ledit" and "rlwrap".
  4098 
  4099 * isatool browser now works with Cygwin as well, using general
  4100 "javapath" function defined in Isabelle process environment.
  4101 
  4102 * YXML notation provides a simple and efficient alternative to
  4103 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  4104 isatool yxml as described in the Isabelle system manual.
  4105 
  4106 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  4107 provides general wrapper for managing an Isabelle process in a robust
  4108 fashion, with ``cooked'' output from stdin/stderr.
  4109 
  4110 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  4111 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  4112 
  4113 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  4114 way of changing the user's settings is via
  4115 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  4116 script.
  4117 
  4118 * Multithreading.max_threads := 0 refers to the number of actual CPU
  4119 cores of the underlying machine, which is a good starting point for
  4120 optimal performance tuning.  The corresponding usedir option -M allows
  4121 "max" as an alias for "0".  WARNING: does not work on certain versions
  4122 of Mac OS (with Poly/ML 5.1).
  4123 
  4124 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  4125 adverse effect of Isabelle flooding interactive front-ends (notably
  4126 ProofGeneral / XEmacs).
  4127 
  4128 
  4129 
  4130 New in Isabelle2007 (November 2007)
  4131 -----------------------------------
  4132 
  4133 *** General ***
  4134 
  4135 * More uniform information about legacy features, notably a
  4136 warning/error of "Legacy feature: ...", depending on the state of the
  4137 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  4138 legacy features will disappear eventually.
  4139 
  4140 * Theory syntax: the header format ``theory A = B + C:'' has been
  4141 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  4142 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  4143 
  4144 * Theory syntax: the old non-Isar theory file format has been
  4145 discontinued altogether.  Note that ML proof scripts may still be used
  4146 with Isar theories; migration is usually quite simple with the ML
  4147 function use_legacy_bindings.  INCOMPATIBILITY.
  4148 
  4149 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  4150 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  4151 quotes.
  4152 
  4153 * Theory loader: be more serious about observing the static theory
  4154 header specifications (including optional directories), but not the
  4155 accidental file locations of previously successful loads.  The strict
  4156 update policy of former update_thy is now already performed by
  4157 use_thy, so the former has been removed; use_thys updates several
  4158 theories simultaneously, just as 'imports' within a theory header
  4159 specification, but without merging the results.  Potential
  4160 INCOMPATIBILITY: may need to refine theory headers and commands
  4161 ROOT.ML which depend on load order.
  4162 
  4163 * Theory loader: optional support for content-based file
  4164 identification, instead of the traditional scheme of full physical
  4165 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  4166 (cf. the system manual).  The new scheme allows to work with
  4167 non-finished theories in persistent session images, such that source
  4168 files may be moved later on without requiring reloads.
  4169 
  4170 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4171 file (with the same base name as the theory) are considered a legacy
  4172 feature, which will disappear eventually. Even now, the theory loader
  4173 no longer maintains dependencies on such files.
  4174 
  4175 * Syntax: the scope for resolving ambiguities via type-inference is
  4176 now limited to individual terms, instead of whole simultaneous
  4177 specifications as before. This greatly reduces the complexity of the
  4178 syntax module and improves flexibility by separating parsing and
  4179 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  4180 'fixes' etc.) are required in rare situations.
  4181 
  4182 * Syntax: constants introduced by new-style packages ('definition',
  4183 'abbreviation' etc.) are passed through the syntax module in
  4184 ``authentic mode''. This means that associated mixfix annotations
  4185 really stick to such constants, independently of potential name space
  4186 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  4187 trees are represented slightly differently, may need to adapt syntax
  4188 translations accordingly. Use CONST marker in 'translations' and
  4189 @{const_syntax} antiquotation in 'parse_translation' etc.
  4190 
  4191 * Legacy goal package: reduced interface to the bare minimum required
  4192 to keep existing proof scripts running.  Most other user-level
  4193 functions are now part of the OldGoals structure, which is *not* open
  4194 by default (consider isatool expandshort before open OldGoals).
  4195 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  4196 these tend to cause confusion about the actual goal (!) context being
  4197 used here, which is not necessarily the same as the_context().
  4198 
  4199 * Command 'find_theorems': supports "*" wild-card in "name:"
  4200 criterion; "with_dups" option.  Certain ProofGeneral versions might
  4201 support a specific search form (see ProofGeneral/CHANGES).
  4202 
  4203 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  4204 by default, which means that "prems" (and also "fixed variables") are
  4205 suppressed from proof state output.  Note that the ProofGeneral
  4206 settings mechanism allows to change and save options persistently, but
  4207 older versions of Isabelle will fail to start up if a negative prems
  4208 limit is imposed.
  4209 
  4210 * Local theory targets may be specified by non-nested blocks of
  4211 ``context/locale/class ... begin'' followed by ``end''.  The body may
  4212 contain definitions, theorems etc., including any derived mechanism
  4213 that has been implemented on top of these primitives.  This concept
  4214 generalizes the existing ``theorem (in ...)'' towards more versatility
  4215 and scalability.
  4216 
  4217 * Proof General interface: proper undo of final 'end' command;
  4218 discontinued Isabelle/classic mode (ML proof scripts).
  4219 
  4220 
  4221 *** Document preparation ***
  4222 
  4223 * Added antiquotation @{theory name} which prints the given name,
  4224 after checking that it refers to a valid ancestor theory in the
  4225 current context.
  4226 
  4227 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  4228 check the given source text as ML type/structure, printing verbatim.
  4229 
  4230 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  4231 "c args == rhs" given in the current context.  (Any number of
  4232 arguments may be given on the LHS.)
  4233 
  4234 
  4235 *** Pure ***
  4236 
  4237 * The 'class' package offers a combination of axclass and locale to
  4238 achieve Haskell-like type classes in Isabelle.  Definitions and
  4239 theorems within a class context produce both relative results (with
  4240 implicit parameters according to the locale context), and polymorphic
  4241 constants with qualified polymorphism (according to the class
  4242 context).  Within the body context of a 'class' target, a separate
  4243 syntax layer ("user space type system") takes care of converting
  4244 between global polymorphic consts and internal locale representation.
  4245 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  4246 "isatool doc classes" provides a tutorial.
  4247 
  4248 * Generic code generator framework allows to generate executable
  4249 code for ML and Haskell (including Isabelle classes).  A short usage
  4250 sketch:
  4251 
  4252     internal compilation:
  4253         export_code <list of constants (term syntax)> in SML
  4254     writing SML code to a file:
  4255         export_code <list of constants (term syntax)> in SML <filename>
  4256     writing OCaml code to a file:
  4257         export_code <list of constants (term syntax)> in OCaml <filename>
  4258     writing Haskell code to a bunch of files:
  4259         export_code <list of constants (term syntax)> in Haskell <filename>
  4260 
  4261     evaluating closed propositions to True/False using code generation:
  4262         method ``eval''
  4263 
  4264 Reasonable default setup of framework in HOL.
  4265 
  4266 Theorem attributs for selecting and transforming function equations theorems:
  4267 
  4268     [code fun]:        select a theorem as function equation for a specific constant
  4269     [code fun del]:    deselect a theorem as function equation for a specific constant
  4270     [code inline]:     select an equation theorem for unfolding (inlining) in place
  4271     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  4272 
  4273 User-defined serializations (target in {SML, OCaml, Haskell}):
  4274 
  4275     code_const <and-list of constants (term syntax)>
  4276       {(target) <and-list of const target syntax>}+
  4277 
  4278     code_type <and-list of type constructors>
  4279       {(target) <and-list of type target syntax>}+
  4280 
  4281     code_instance <and-list of instances>
  4282       {(target)}+
  4283         where instance ::= <type constructor> :: <class>
  4284 
  4285     code_class <and_list of classes>
  4286       {(target) <and-list of class target syntax>}+
  4287         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4288 
  4289 code_instance and code_class only are effective to target Haskell.
  4290 
  4291 For example usage see src/HOL/ex/Codegenerator.thy and
  4292 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4293 generation from Isabelle/HOL theories is available via "isatool doc
  4294 codegen".
  4295 
  4296 * Code generator: consts in 'consts_code' Isar commands are now
  4297 referred to by usual term syntax (including optional type
  4298 annotations).
  4299 
  4300 * Command 'no_translations' removes translation rules from theory
  4301 syntax.
  4302 
  4303 * Overloaded definitions are now actually checked for acyclic
  4304 dependencies.  The overloading scheme is slightly more general than
  4305 that of Haskell98, although Isabelle does not demand an exact
  4306 correspondence to type class and instance declarations.
  4307 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4308 exotic versions of overloading -- at the discretion of the user!
  4309 
  4310 Polymorphic constants are represented via type arguments, i.e. the
  4311 instantiation that matches an instance against the most general
  4312 declaration given in the signature.  For example, with the declaration
  4313 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4314 as c(nat).  Overloading is essentially simultaneous structural
  4315 recursion over such type arguments.  Incomplete specification patterns
  4316 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4317 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4318 Command 'print_theory' outputs the normalized system of recursive
  4319 equations, see section "definitions".
  4320 
  4321 * Configuration options are maintained within the theory or proof
  4322 context (with name and type bool/int/string), providing a very simple
  4323 interface to a poor-man's version of general context data.  Tools may
  4324 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4325 these values using Config.get etc.  Users may change options via an
  4326 associated attribute of the same name.  This form of context
  4327 declaration works particularly well with commands 'declare' or
  4328 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4329 very easy to avoid global references, which would not observe Isar
  4330 toplevel undo/redo and fail to work with multithreading.
  4331 
  4332 Various global ML references of Pure and HOL have been turned into
  4333 configuration options:
  4334 
  4335   Unify.search_bound		unify_search_bound
  4336   Unify.trace_bound		unify_trace_bound
  4337   Unify.trace_simp		unify_trace_simp
  4338   Unify.trace_types		unify_trace_types
  4339   Simplifier.simp_depth_limit	simp_depth_limit
  4340   Blast.depth_limit		blast_depth_limit
  4341   DatatypeProp.dtK		datatype_distinctness_limit
  4342   fast_arith_neq_limit  	fast_arith_neq_limit
  4343   fast_arith_split_limit	fast_arith_split_limit
  4344 
  4345 * Named collections of theorems may be easily installed as context
  4346 data using the functor NamedThmsFun (see also
  4347 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4348 attributes; there is also a toplevel print command.  This facility is
  4349 just a common case of general context data, which is the preferred way
  4350 for anything more complex than just a list of facts in canonical
  4351 order.
  4352 
  4353 * Isar: command 'declaration' augments a local theory by generic
  4354 declaration functions written in ML.  This enables arbitrary content
  4355 being added to the context, depending on a morphism that tells the
  4356 difference of the original declaration context wrt. the application
  4357 context encountered later on.
  4358 
  4359 * Isar: proper interfaces for simplification procedures.  Command
  4360 'simproc_setup' declares named simprocs (with match patterns, and body
  4361 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4362 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4363 
  4364 * Isar: an extra pair of brackets around attribute declarations
  4365 abbreviates a theorem reference involving an internal dummy fact,
  4366 which will be ignored later --- only the effect of the attribute on
  4367 the background context will persist.  This form of in-place
  4368 declarations is particularly useful with commands like 'declare' and
  4369 'using', for example ``have A using [[simproc a]] by simp''.
  4370 
  4371 * Isar: method "assumption" (and implicit closing of subproofs) now
  4372 takes simple non-atomic goal assumptions into account: after applying
  4373 an assumption as a rule the resulting subgoals are solved by atomic
  4374 assumption steps.  This is particularly useful to finish 'obtain'
  4375 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4376 without referring to the original premise "!!x. P x ==> thesis" in the
  4377 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4378 more permissive.
  4379 
  4380 * Isar: implicit use of prems from the Isar proof context is
  4381 considered a legacy feature.  Common applications like ``have A .''
  4382 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4383 referencing facts explicitly here improves readability and
  4384 maintainability of proof texts.
  4385 
  4386 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4387 the obtained context from the course of reasoning!  For example:
  4388 
  4389   assume "EX x y. A x & B y"   -- "any previous fact"
  4390   then guess x and y by clarify
  4391 
  4392 This technique is potentially adventurous, depending on the facts and
  4393 proof tools being involved here.
  4394 
  4395 * Isar: known facts from the proof context may be specified as literal
  4396 propositions, using ASCII back-quote syntax.  This works wherever
  4397 named facts used to be allowed so far, in proof commands, proof
  4398 methods, attributes etc.  Literal facts are retrieved from the context
  4399 according to unification of type and term parameters.  For example,
  4400 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4401 theorems in the current context, then these are valid literal facts:
  4402 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4403 
  4404 There is also a proof method "fact" which does the same composition
  4405 for explicit goal states, e.g. the following proof texts coincide with
  4406 certain special cases of literal facts:
  4407 
  4408   have "A" by fact                 ==  note `A`
  4409   have "A ==> B" by fact           ==  note `A ==> B`
  4410   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4411   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4412 
  4413 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4414 outer syntax.  Thus symbolic identifiers may be used without
  4415 additional white space in declarations like this: ``assume *: A''.
  4416 
  4417 * Isar: 'print_facts' prints all local facts of the current context,
  4418 both named and unnamed ones.
  4419 
  4420 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4421 
  4422   def x == "t" and y == "u"
  4423 
  4424 * Isar: added command 'unfolding', which is structurally similar to
  4425 'using', but affects both the goal state and facts by unfolding given
  4426 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4427 'unfolded' attribute may be replaced by first-class proof text.
  4428 
  4429 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4430 and command 'unfolding' now all support object-level equalities
  4431 (potentially conditional).  The underlying notion of rewrite rule is
  4432 analogous to the 'rule_format' attribute, but *not* that of the
  4433 Simplifier (which is usually more generous).
  4434 
  4435 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4436 premises of a theorem by n. Useful in conjunction with drule.
  4437 
  4438 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4439 method expression within a sandbox consisting of the first N
  4440 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4441 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4442 simplifies all new goals that emerge from applying rule foo to the
  4443 originally first one.
  4444 
  4445 * Isar: schematic goals are no longer restricted to higher-order
  4446 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4447 expected.
  4448 
  4449 * Isar: the conclusion of a long theorem statement is now either
  4450 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4451 (essentially a disjunction of cases with local parameters and
  4452 assumptions).  The latter allows to express general elimination rules
  4453 adequately; in this notation common elimination rules look like this:
  4454 
  4455   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4456     assumes "EX x. P x"
  4457     obtains x where "P x"
  4458 
  4459   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4460     assumes "A & B"
  4461     obtains A and B
  4462 
  4463   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4464     assumes "A | B"
  4465     obtains
  4466       A
  4467     | B
  4468 
  4469 The subsequent classical rules even refer to the formal "thesis"
  4470 explicitly:
  4471 
  4472   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4473     obtains "~ thesis"
  4474 
  4475   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4476     obtains "thesis ==> something"
  4477 
  4478 The actual proof of an 'obtains' statement is analogous to that of the
  4479 Isar proof element 'obtain', only that there may be several cases.
  4480 Optional case names may be specified in parentheses; these will be
  4481 available both in the present proof and as annotations in the
  4482 resulting rule, for later use with the 'cases' method (cf. attribute
  4483 case_names).
  4484 
  4485 * Isar: the assumptions of a long theorem statement are available as
  4486 "assms" fact in the proof context.  This is more appropriate than the
  4487 (historical) "prems", which refers to all assumptions of the current
  4488 context, including those from the target locale, proof body etc.
  4489 
  4490 * Isar: 'print_statement' prints theorems from the current theory or
  4491 proof context in long statement form, according to the syntax of a
  4492 top-level lemma.
  4493 
  4494 * Isar: 'obtain' takes an optional case name for the local context
  4495 introduction rule (default "that").
  4496 
  4497 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4498 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4499 to occur.
  4500 
  4501 * Pure: syntax "CONST name" produces a fully internalized constant
  4502 according to the current context.  This is particularly useful for
  4503 syntax translations that should refer to internal constant
  4504 representations independently of name spaces.
  4505 
  4506 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4507 instead of "FOO ". This allows multiple binder declarations to coexist
  4508 in the same context.  INCOMPATIBILITY.
  4509 
  4510 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4511 primitive that also works in a locale context (both for constants and
  4512 fixed variables). Type declaration and internal syntactic representation
  4513 of given constants retrieved from the context. Likewise, the
  4514 'no_notation' command allows to remove given syntax annotations from the
  4515 current context.
  4516 
  4517 * Isar/locales: new derived specification elements 'axiomatization',
  4518 'definition', 'abbreviation', which support type-inference, admit
  4519 object-level specifications (equality, equivalence).  See also the
  4520 isar-ref manual.  Examples:
  4521 
  4522   axiomatization
  4523     eq  (infix "===" 50) where
  4524     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4525 
  4526   definition "f x y = x + y + 1"
  4527   definition g where "g x = f x x"
  4528 
  4529   abbreviation
  4530     neq  (infix "=!=" 50) where
  4531     "x =!= y == ~ (x === y)"
  4532 
  4533 These specifications may be also used in a locale context.  Then the
  4534 constants being introduced depend on certain fixed parameters, and the
  4535 constant name is qualified by the locale base name.  An internal
  4536 abbreviation takes care for convenient input and output, making the
  4537 parameters implicit and using the original short name.  See also
  4538 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4539 entities from a monomorphic theory.
  4540 
  4541 Presently, abbreviations are only available 'in' a target locale, but
  4542 not inherited by general import expressions.  Also note that
  4543 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4544 'translations' in common applications.  The "no_abbrevs" print mode
  4545 prevents folding of abbreviations in term output.
  4546 
  4547 Concrete syntax is attached to specified constants in internal form,
  4548 independently of name spaces.  The parse tree representation is
  4549 slightly different -- use 'notation' instead of raw 'syntax', and
  4550 'translations' with explicit "CONST" markup to accommodate this.
  4551 
  4552 * Pure/Isar: unified syntax for new-style specification mechanisms
  4553 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4554 full type inference and dummy patterns ("_").  For example:
  4555 
  4556   definition "K x _ = x"
  4557 
  4558   inductive conj for A B
  4559   where "A ==> B ==> conj A B"
  4560 
  4561 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4562 the current context.  Print mode "no_abbrevs" prevents inversion of
  4563 abbreviations on output.
  4564 
  4565 * Isar/locales: improved parameter handling: use of locales "var" and
  4566 "struct" no longer necessary; - parameter renamings are no longer
  4567 required to be injective.  For example, this allows to define
  4568 endomorphisms as locale endom = homom mult mult h.
  4569 
  4570 * Isar/locales: changed the way locales with predicates are defined.
  4571 Instead of accumulating the specification, the imported expression is
  4572 now an interpretation.  INCOMPATIBILITY: different normal form of
  4573 locale expressions.  In particular, in interpretations of locales with
  4574 predicates, goals repesenting already interpreted fragments are not
  4575 removed automatically.  Use methods `intro_locales' and
  4576 `unfold_locales'; see below.
  4577 
  4578 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4579 provide backward reasoning on locales predicates.  The methods are
  4580 aware of interpretations and discharge corresponding goals.
  4581 `intro_locales' is less aggressive then `unfold_locales' and does not
  4582 unfold predicates to assumptions.
  4583 
  4584 * Isar/locales: the order in which locale fragments are accumulated
  4585 has changed.  This enables to override declarations from fragments due
  4586 to interpretations -- for example, unwanted simp rules.
  4587 
  4588 * Isar/locales: interpretation in theories and proof contexts has been
  4589 extended.  One may now specify (and prove) equations, which are
  4590 unfolded in interpreted theorems.  This is useful for replacing
  4591 defined concepts (constants depending on locale parameters) by
  4592 concepts already existing in the target context.  Example:
  4593 
  4594   interpretation partial_order ["op <= :: [int, int] => bool"]
  4595     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4596 
  4597 Typically, the constant `partial_order.less' is created by a
  4598 definition specification element in the context of locale
  4599 partial_order.
  4600 
  4601 * Method "induct": improved internal context management to support
  4602 local fixes and defines on-the-fly. Thus explicit meta-level
  4603 connectives !!  and ==> are rarely required anymore in inductive goals
  4604 (using object-logic connectives for this purpose has been long
  4605 obsolete anyway). Common proof patterns are explained in
  4606 src/HOL/Induct/Common_Patterns.thy, see also
  4607 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4608 examples.
  4609 
  4610 * Method "induct": improved handling of simultaneous goals. Instead of
  4611 introducing object-level conjunction, the statement is now split into
  4612 several conclusions, while the corresponding symbolic cases are nested
  4613 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4614 see src/HOL/Induct/Common_Patterns.thy, for example.
  4615 
  4616 * Method "induct": mutual induction rules are now specified as a list
  4617 of rule sharing the same induction cases. HOL packages usually provide
  4618 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4619 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4620 mutual induction rules differently, i.e. like this:
  4621 
  4622   (induct rule: foo_bar.inducts)
  4623   (induct set: foo bar)
  4624   (induct pred: foo bar)
  4625   (induct type: foo bar)
  4626 
  4627 The ML function ProjectRule.projections turns old-style rules into the
  4628 new format.
  4629 
  4630 * Method "coinduct": dual of induction, see
  4631 src/HOL/Library/Coinductive_List.thy for various examples.
  4632 
  4633 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4634 considered a legacy feature.
  4635 
  4636 * Attribute "symmetric" produces result with standardized schematic
  4637 variables (index 0).  Potential INCOMPATIBILITY.
  4638 
  4639 * Simplifier: by default the simplifier trace only shows top level
  4640 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4641 default. Thus there is less danger of being flooded by the trace. The
  4642 trace indicates where parts have been suppressed.
  4643   
  4644 * Provers/classical: removed obsolete classical version of elim_format
  4645 attribute; classical elim/dest rules are now treated uniformly when
  4646 manipulating the claset.
  4647 
  4648 * Provers/classical: stricter checks to ensure that supplied intro,
  4649 dest and elim rules are well-formed; dest and elim rules must have at
  4650 least one premise.
  4651 
  4652 * Provers/classical: attributes dest/elim/intro take an optional
  4653 weight argument for the rule (just as the Pure versions).  Weights are
  4654 ignored by automated tools, but determine the search order of single
  4655 rule steps.
  4656 
  4657 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4658 where the body does not mention the bound variable.  Note that dummy
  4659 patterns implicitly depend on their context of bounds, which makes
  4660 "{_. _}" match any set comprehension as expected.  Potential
  4661 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4662 constant "_idtdummy" in the binding position.
  4663 
  4664 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4665 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4666 for example "A -> B" => "Pi A (%_. B)".
  4667 
  4668 * Pure: 'class_deps' command visualizes the subclass relation, using
  4669 the graph browser tool.
  4670 
  4671 * Pure: 'print_theory' now suppresses certain internal declarations by
  4672 default; use '!' option for full details.
  4673 
  4674 
  4675 *** HOL ***
  4676 
  4677 * Method "metis" proves goals by applying the Metis general-purpose
  4678 resolution prover (see also http://gilith.com/software/metis/).
  4679 Examples are in the directory MetisExamples.  WARNING: the
  4680 Isabelle/HOL-Metis integration does not yet work properly with
  4681 multi-threading.
  4682   
  4683 * Command 'sledgehammer' invokes external automatic theorem provers as
  4684 background processes.  It generates calls to the "metis" method if
  4685 successful. These can be pasted into the proof.  Users do not have to
  4686 wait for the automatic provers to return.  WARNING: does not really
  4687 work with multi-threading.
  4688 
  4689 * New "auto_quickcheck" feature tests outermost goal statements for
  4690 potential counter-examples.  Controlled by ML references
  4691 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4692 5000 milliseconds).  Fails silently if statements is outside of
  4693 executable fragment, or any other codgenerator problem occurs.
  4694 
  4695 * New constant "undefined" with axiom "undefined x = undefined".
  4696 
  4697 * Added class "HOL.eq", allowing for code generation with polymorphic
  4698 equality.
  4699 
  4700 * Some renaming of class constants due to canonical name prefixing in
  4701 the new 'class' package:
  4702 
  4703     HOL.abs ~> HOL.abs_class.abs
  4704     HOL.divide ~> HOL.divide_class.divide
  4705     0 ~> HOL.zero_class.zero
  4706     1 ~> HOL.one_class.one
  4707     op + ~> HOL.plus_class.plus
  4708     op - ~> HOL.minus_class.minus
  4709     uminus ~> HOL.minus_class.uminus
  4710     op * ~> HOL.times_class.times
  4711     op < ~> HOL.ord_class.less
  4712     op <= > HOL.ord_class.less_eq
  4713     Nat.power ~> Power.power_class.power
  4714     Nat.size ~> Nat.size_class.size
  4715     Numeral.number_of ~> Numeral.number_class.number_of
  4716     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4717     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4718     Orderings.min ~> Orderings.ord_class.min
  4719     Orderings.max ~> Orderings.ord_class.max
  4720     Divides.op div ~> Divides.div_class.div
  4721     Divides.op mod ~> Divides.div_class.mod
  4722     Divides.op dvd ~> Divides.div_class.dvd
  4723 
  4724 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4725 
  4726 a) User-defined constants using any of the names "plus", "minus",
  4727 "times", "less" or "less_eq". The standard syntax translations for
  4728 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4729 names.
  4730 
  4731 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4732 INCOMPATIBILITY: use more specific names.
  4733 
  4734 c) Permutative equations (e.g. "a + b = b + a")
  4735 Since the change of names also changes the order of terms, permutative
  4736 rewrite rules may get applied in a different order. Experience shows
  4737 that this is rarely the case (only two adaptions in the whole Isabelle
  4738 distribution).  INCOMPATIBILITY: rewrite proofs
  4739 
  4740 d) ML code directly refering to constant names
  4741 This in general only affects hand-written proof tactics, simprocs and
  4742 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4743 Consider using @{const_name} antiquotation.
  4744 
  4745 * New class "default" with associated constant "default".
  4746 
  4747 * Function "sgn" is now overloaded and available on int, real, complex
  4748 (and other numeric types), using class "sgn".  Two possible defs of
  4749 sgn are given as equational assumptions in the classes sgn_if and
  4750 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4751 INCOMPATIBILITY.
  4752 
  4753 * Locale "partial_order" now unified with class "order" (cf. theory
  4754 Orderings), added parameter "less".  INCOMPATIBILITY.
  4755 
  4756 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4757 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4758 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4759 
  4760 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4761 changed order of proof goals in instance proofs.
  4762 
  4763 * The transitivity reasoner for partial and linear orders is set up
  4764 for classes "order" and "linorder".  Instances of the reasoner are available
  4765 in all contexts importing or interpreting the corresponding locales.
  4766 Method "order" invokes the reasoner separately; the reasoner
  4767 is also integrated with the Simplifier as a solver.  Diagnostic
  4768 command 'print_orders' shows the available instances of the reasoner
  4769 in the current context.
  4770 
  4771 * Localized monotonicity predicate in theory "Orderings"; integrated
  4772 lemmas max_of_mono and min_of_mono with this predicate.
  4773 INCOMPATIBILITY.
  4774 
  4775 * Formulation of theorem "dense" changed slightly due to integration
  4776 with new class dense_linear_order.
  4777 
  4778 * Uniform lattice theory development in HOL.
  4779 
  4780     constants "meet" and "join" now named "inf" and "sup"
  4781     constant "Meet" now named "Inf"
  4782 
  4783     classes "meet_semilorder" and "join_semilorder" now named
  4784       "lower_semilattice" and "upper_semilattice"
  4785     class "lorder" now named "lattice"
  4786     class "comp_lat" now named "complete_lattice"
  4787 
  4788     Instantiation of lattice classes allows explicit definitions
  4789     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4790 
  4791   INCOMPATIBILITY.  Theorem renames:
  4792 
  4793     meet_left_le            ~> inf_le1
  4794     meet_right_le           ~> inf_le2
  4795     join_left_le            ~> sup_ge1
  4796     join_right_le           ~> sup_ge2
  4797     meet_join_le            ~> inf_sup_ord
  4798     le_meetI                ~> le_infI
  4799     join_leI                ~> le_supI
  4800     le_meet                 ~> le_inf_iff
  4801     le_join                 ~> ge_sup_conv
  4802     meet_idempotent         ~> inf_idem
  4803     join_idempotent         ~> sup_idem
  4804     meet_comm               ~> inf_commute
  4805     join_comm               ~> sup_commute
  4806     meet_leI1               ~> le_infI1
  4807     meet_leI2               ~> le_infI2
  4808     le_joinI1               ~> le_supI1
  4809     le_joinI2               ~> le_supI2
  4810     meet_assoc              ~> inf_assoc
  4811     join_assoc              ~> sup_assoc
  4812     meet_left_comm          ~> inf_left_commute
  4813     meet_left_idempotent    ~> inf_left_idem
  4814     join_left_comm          ~> sup_left_commute
  4815     join_left_idempotent    ~> sup_left_idem
  4816     meet_aci                ~> inf_aci
  4817     join_aci                ~> sup_aci
  4818     le_def_meet             ~> le_iff_inf
  4819     le_def_join             ~> le_iff_sup
  4820     join_absorp2            ~> sup_absorb2
  4821     join_absorp1            ~> sup_absorb1
  4822     meet_absorp1            ~> inf_absorb1
  4823     meet_absorp2            ~> inf_absorb2
  4824     meet_join_absorp        ~> inf_sup_absorb
  4825     join_meet_absorp        ~> sup_inf_absorb
  4826     distrib_join_le         ~> distrib_sup_le
  4827     distrib_meet_le         ~> distrib_inf_le
  4828 
  4829     add_meet_distrib_left   ~> add_inf_distrib_left
  4830     add_join_distrib_left   ~> add_sup_distrib_left
  4831     is_join_neg_meet        ~> is_join_neg_inf
  4832     is_meet_neg_join        ~> is_meet_neg_sup
  4833     add_meet_distrib_right  ~> add_inf_distrib_right
  4834     add_join_distrib_right  ~> add_sup_distrib_right
  4835     add_meet_join_distribs  ~> add_sup_inf_distribs
  4836     join_eq_neg_meet        ~> sup_eq_neg_inf
  4837     meet_eq_neg_join        ~> inf_eq_neg_sup
  4838     add_eq_meet_join        ~> add_eq_inf_sup
  4839     meet_0_imp_0            ~> inf_0_imp_0
  4840     join_0_imp_0            ~> sup_0_imp_0
  4841     meet_0_eq_0             ~> inf_0_eq_0
  4842     join_0_eq_0             ~> sup_0_eq_0
  4843     neg_meet_eq_join        ~> neg_inf_eq_sup
  4844     neg_join_eq_meet        ~> neg_sup_eq_inf
  4845     join_eq_if              ~> sup_eq_if
  4846 
  4847     mono_meet               ~> mono_inf
  4848     mono_join               ~> mono_sup
  4849     meet_bool_eq            ~> inf_bool_eq
  4850     join_bool_eq            ~> sup_bool_eq
  4851     meet_fun_eq             ~> inf_fun_eq
  4852     join_fun_eq             ~> sup_fun_eq
  4853     meet_set_eq             ~> inf_set_eq
  4854     join_set_eq             ~> sup_set_eq
  4855     meet1_iff               ~> inf1_iff
  4856     meet2_iff               ~> inf2_iff
  4857     meet1I                  ~> inf1I
  4858     meet2I                  ~> inf2I
  4859     meet1D1                 ~> inf1D1
  4860     meet2D1                 ~> inf2D1
  4861     meet1D2                 ~> inf1D2
  4862     meet2D2                 ~> inf2D2
  4863     meet1E                  ~> inf1E
  4864     meet2E                  ~> inf2E
  4865     join1_iff               ~> sup1_iff
  4866     join2_iff               ~> sup2_iff
  4867     join1I1                 ~> sup1I1
  4868     join2I1                 ~> sup2I1
  4869     join1I1                 ~> sup1I1
  4870     join2I2                 ~> sup1I2
  4871     join1CI                 ~> sup1CI
  4872     join2CI                 ~> sup2CI
  4873     join1E                  ~> sup1E
  4874     join2E                  ~> sup2E
  4875 
  4876     is_meet_Meet            ~> is_meet_Inf
  4877     Meet_bool_def           ~> Inf_bool_def
  4878     Meet_fun_def            ~> Inf_fun_def
  4879     Meet_greatest           ~> Inf_greatest
  4880     Meet_lower              ~> Inf_lower
  4881     Meet_set_def            ~> Inf_set_def
  4882 
  4883     Sup_def                 ~> Sup_Inf
  4884     Sup_bool_eq             ~> Sup_bool_def
  4885     Sup_fun_eq              ~> Sup_fun_def
  4886     Sup_set_eq              ~> Sup_set_def
  4887 
  4888     listsp_meetI            ~> listsp_infI
  4889     listsp_meet_eq          ~> listsp_inf_eq
  4890 
  4891     meet_min                ~> inf_min
  4892     join_max                ~> sup_max
  4893 
  4894 * Added syntactic class "size"; overloaded constant "size" now has
  4895 type "'a::size ==> bool"
  4896 
  4897 * Internal reorganisation of `size' of datatypes: size theorems
  4898 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4899 simplification rules by default!); theorems "prod.size" now named
  4900 "*.size".
  4901 
  4902 * Class "div" now inherits from class "times" rather than "type".
  4903 INCOMPATIBILITY.
  4904 
  4905 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4906 Linorder etc.  have disappeared; operations defined in terms of
  4907 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4908 
  4909 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4910 
  4911 * HOL-Word: New extensive library and type for generic, fixed size
  4912 machine words, with arithmetic, bit-wise, shifting and rotating
  4913 operations, reflection into int, nat, and bool lists, automation for
  4914 linear arithmetic (by automatic reflection into nat or int), including
  4915 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4916 arithmetic type classes, supporting automatic simplification of
  4917 numerals on all operations.
  4918 
  4919 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4920 
  4921 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4922 
  4923 * Code generator library theories:
  4924   - Code_Integer represents HOL integers by big integer literals in target
  4925     languages.
  4926   - Code_Char represents HOL characters by character literals in target
  4927     languages.
  4928   - Code_Char_chr like Code_Char, but also offers treatment of character
  4929     codes; includes Code_Integer.
  4930   - Executable_Set allows to generate code for finite sets using lists.
  4931   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4932     denominator).
  4933   - Executable_Real implements a subset of real numbers, namly those
  4934     representable by rational numbers.
  4935   - Efficient_Nat implements natural numbers by integers, which in general will
  4936     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4937     includes Code_Integer.
  4938   - Code_Index provides an additional datatype index which is mapped to
  4939     target-language built-in integers.
  4940   - Code_Message provides an additional datatype message_string which is isomorphic to
  4941     strings; messages are mapped to target-language strings.
  4942 
  4943 * New package for inductive predicates
  4944 
  4945   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4946 
  4947     inductive
  4948       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4949       for z_1 :: U_1 and ... and z_n :: U_m
  4950     where
  4951       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4952     | ...
  4953 
  4954   with full support for type-inference, rather than
  4955 
  4956     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4957 
  4958     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4959     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4960 
  4961     inductive "s z_1 ... z_m"
  4962     intros
  4963       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4964       ...
  4965 
  4966   For backward compatibility, there is a wrapper allowing inductive
  4967   sets to be defined with the new package via
  4968 
  4969     inductive_set
  4970       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4971       for z_1 :: U_1 and ... and z_n :: U_m
  4972     where
  4973       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4974     | ...
  4975 
  4976   or
  4977 
  4978     inductive_set
  4979       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4980       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4981       for z_1 :: U_1 and ... and z_n :: U_m
  4982     where
  4983       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4984     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4985     | ...
  4986 
  4987   if the additional syntax "p ..." is required.
  4988 
  4989   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4990   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4991 
  4992   INCOMPATIBILITIES:
  4993 
  4994   - Since declaration and definition of inductive sets or predicates
  4995     is no longer separated, abbreviations involving the newly
  4996     introduced sets or predicates must be specified together with the
  4997     introduction rules after the 'where' keyword (see above), rather
  4998     than before the actual inductive definition.
  4999 
  5000   - The variables in induction and elimination rules are now
  5001     quantified in the order of their occurrence in the introduction
  5002     rules, rather than in alphabetical order. Since this may break
  5003     some proofs, these proofs either have to be repaired, e.g. by
  5004     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  5005     statements of the form
  5006 
  5007       case (rule_i a_i_1 ... a_i_{k_i})
  5008 
  5009     or the old order of quantification has to be restored by explicitly adding
  5010     meta-level quantifiers in the introduction rules, i.e.
  5011 
  5012       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  5013 
  5014   - The format of the elimination rules is now
  5015 
  5016       p z_1 ... z_m x_1 ... x_n ==>
  5017         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5018         ==> ... ==> P
  5019 
  5020     for predicates and
  5021 
  5022       (x_1, ..., x_n) : s z_1 ... z_m ==>
  5023         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5024         ==> ... ==> P
  5025 
  5026     for sets rather than
  5027 
  5028       x : s z_1 ... z_m ==>
  5029         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  5030         ==> ... ==> P
  5031 
  5032     This may require terms in goals to be expanded to n-tuples
  5033     (e.g. using case_tac or simplification with the split_paired_all
  5034     rule) before the above elimination rule is applicable.
  5035 
  5036   - The elimination or case analysis rules for (mutually) inductive
  5037     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  5038     list of rules "p_1_..._p_k.elims" is no longer available.
  5039 
  5040 * New package "function"/"fun" for general recursive functions,
  5041 supporting mutual and nested recursion, definitions in local contexts,
  5042 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  5043 for small examples, and the separate tutorial on the function
  5044 package. The old recdef "package" is still available as before, but
  5045 users are encouraged to use the new package.
  5046 
  5047 * Method "lexicographic_order" automatically synthesizes termination
  5048 relations as lexicographic combinations of size measures. 
  5049 
  5050 * Case-expressions allow arbitrary constructor-patterns (including
  5051 "_") and take their order into account, like in functional
  5052 programming.  Internally, this is translated into nested
  5053 case-expressions; missing cases are added and mapped to the predefined
  5054 constant "undefined". In complicated cases printing may no longer show
  5055 the original input but the internal form. Lambda-abstractions allow
  5056 the same form of pattern matching: "% pat1 => e1 | ..." is an
  5057 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  5058 variable.
  5059 
  5060 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  5061 is an abbreviation for "of_nat :: nat => int". The simplification
  5062 rules for "of_nat" have been changed to work like "int" did
  5063 previously.  Potential INCOMPATIBILITY:
  5064   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  5065   - of_nat_diff and of_nat_mult are no longer default simp rules
  5066 
  5067 * Method "algebra" solves polynomial equations over (semi)rings using
  5068 Groebner bases. The (semi)ring structure is defined by locales and the
  5069 tool setup depends on that generic context. Installing the method for
  5070 a specific type involves instantiating the locale and possibly adding
  5071 declarations for computation on the coefficients.  The method is
  5072 already instantiated for natural numbers and for the axiomatic class
  5073 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  5074 CALCULEMUS 2007 for the general principles underlying this
  5075 architecture of context-aware proof-tools.
  5076 
  5077 * Method "ferrack" implements quantifier elimination over
  5078 special-purpose dense linear orders using locales (analogous to
  5079 "algebra"). The method is already installed for class
  5080 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  5081 rat, etc.
  5082 
  5083 * Former constant "List.op @" now named "List.append".  Use ML
  5084 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  5085 circumvent possible incompatibilities when working on ML level.
  5086 
  5087 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  5088 
  5089 * New function listsum :: 'a list => 'a for arbitrary monoids.
  5090 Special syntax: "SUM x <- xs. f x" (and latex variants)
  5091 
  5092 * New syntax for Haskell-like list comprehension (input only), eg.
  5093 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  5094 
  5095 * The special syntax for function "filter" has changed from [x :
  5096 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  5097 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  5098 
  5099 * [a..b] is now defined for arbitrary linear orders.  It used to be
  5100 defined on nat only, as an abbreviation for [a..<Suc b]
  5101 INCOMPATIBILITY.
  5102 
  5103 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  5104 
  5105 * New functions "sorted" and "sort" in src/HOL/List.thy.
  5106 
  5107 * New lemma collection field_simps (an extension of ring_simps) for
  5108 manipulating (in)equations involving division. Multiplies with all
  5109 denominators that can be proved to be non-zero (in equations) or
  5110 positive/negative (in inequations).
  5111 
  5112 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  5113 have been improved and renamed to ring_simps, group_simps and
  5114 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  5115 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  5116 
  5117 * Theory Library/Commutative_Ring: switched from recdef to function
  5118 package; constants add, mul, pow now curried.  Infix syntax for
  5119 algebraic operations.
  5120 
  5121 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  5122 INCOMPATIBILITY.
  5123 
  5124 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  5125 INCOMPATIBILITY.
  5126 
  5127 * HOL/records: generalised field-update to take a function on the
  5128 field rather than the new value: r(|A := x|) is translated to A_update
  5129 (K x) r The K-combinator that is internally used is called K_record.
  5130 INCOMPATIBILITY: Usage of the plain update functions has to be
  5131 adapted.
  5132  
  5133 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  5134 * x = 0, which are required for a semiring.  Richer structures do not
  5135 inherit from semiring_0 anymore, because this property is a theorem
  5136 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  5137 there is more to prove, but this is mostly trivial.
  5138 
  5139 * Class "recpower" is generalized to arbitrary monoids, not just
  5140 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  5141 commutativity or semiring properties additionally.
  5142 
  5143 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  5144 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  5145 better use 'abbreviation'.
  5146 
  5147 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  5148 
  5149 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  5150 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  5151 significant changes for setting up numeral syntax for types:
  5152   - New constants Numeral.pred and Numeral.succ instead
  5153       of former Numeral.bin_pred and Numeral.bin_succ.
  5154   - Use integer operations instead of bin_add, bin_mult and so on.
  5155   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  5156   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  5157 
  5158 See src/HOL/Integ/IntArith.thy for an example setup.
  5159 
  5160 * Command 'normal_form' computes the normal form of a term that may
  5161 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  5162 produces ``[b, c, a]'' (without proof).  This command is suitable for
  5163 heavy-duty computations because the functions are compiled to ML
  5164 first.  Correspondingly, a method "normalization" is provided.  See
  5165 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  5166 
  5167 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  5168 25 like -->); output depends on the "iff" print_mode, the default is
  5169 "A = B" (with priority 50).
  5170 
  5171 * Relations less (<) and less_eq (<=) are also available on type bool.
  5172 Modified syntax to disallow nesting without explicit parentheses,
  5173 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  5174 INCOMPATIBILITY.
  5175 
  5176 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  5177 
  5178 * Relation composition operator "op O" now has precedence 75 and binds
  5179 stronger than union and intersection. INCOMPATIBILITY.
  5180 
  5181 * The old set interval syntax "{m..n(}" (and relatives) has been
  5182 removed.  Use "{m..<n}" (and relatives) instead.
  5183 
  5184 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  5185 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  5186 ``declare [[simproc del: neq]]''.
  5187 
  5188 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  5189 True/False.
  5190 
  5191 * Theorem Cons_eq_map_conv no longer declared as "simp".
  5192 
  5193 * Theorem setsum_mult renamed to setsum_right_distrib.
  5194 
  5195 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  5196 ``rule'' method.
  5197 
  5198 * Reimplemented methods "sat" and "satx", with several improvements:
  5199 goals no longer need to be stated as "<prems> ==> False", equivalences
  5200 (i.e. "=" on type bool) are handled, variable names of the form
  5201 "lit_<n>" are no longer reserved, significant speedup.
  5202 
  5203 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  5204 zChaff is still supported as well.
  5205 
  5206 * 'inductive' and 'datatype': provide projections of mutual rules,
  5207 bundled as foo_bar.inducts;
  5208 
  5209 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  5210 Library.
  5211 
  5212 * Library: moved theory Accessible_Part to main HOL.
  5213 
  5214 * Library: added theory Coinductive_List of potentially infinite lists
  5215 as greatest fixed-point.
  5216 
  5217 * Library: added theory AssocList which implements (finite) maps as
  5218 association lists.
  5219 
  5220 * Method "evaluation" solves goals (i.e. a boolean expression)
  5221 efficiently by compiling it to ML.  The goal is "proved" (via an
  5222 oracle) if it evaluates to True.
  5223 
  5224 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  5225 also when invoked by the simplifier.  This results in the Simplifier
  5226 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  5227 Configuration option fast_arith_split_limit=0 recovers the old
  5228 behavior.
  5229 
  5230 * Support for hex (0x20) and binary (0b1001) numerals.
  5231 
  5232 * New method: reify eqs (t), where eqs are equations for an
  5233 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  5234 parameter, computes a term s::'b and a list xs::'a list and proves the
  5235 theorem I xs s = t. This is also known as reification or quoting. The
  5236 resulting theorem is applied to the subgoal to substitute t with I xs
  5237 s.  If t is omitted, the subgoal itself is reified.
  5238 
  5239 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  5240 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  5241 where f is supposed to be a computable function (in the sense of code
  5242 generattion). The method uses reify to compute s and xs as above then
  5243 applies corr_thm and uses normalization by evaluation to "prove" f s =
  5244 r and finally gets the theorem t = r, which is again applied to the
  5245 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  5246 
  5247 * Reflection: Automatic reification now handels binding, an example is
  5248 available in src/HOL/ex/ReflectionEx.thy
  5249 
  5250 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  5251 command 'statespace' that is similar to 'record', but introduces an
  5252 abstract specification based on the locale infrastructure instead of
  5253 HOL types.  This leads to extra flexibility in composing state spaces,
  5254 in particular multiple inheritance and renaming of components.
  5255 
  5256 
  5257 *** HOL-Complex ***
  5258 
  5259 * Hyperreal: Functions root and sqrt are now defined on negative real
  5260 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  5261 Nonnegativity side conditions have been removed from many lemmas, so
  5262 that more subgoals may now be solved by simplification; potential
  5263 INCOMPATIBILITY.
  5264 
  5265 * Real: new type classes formalize real normed vector spaces and
  5266 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  5267 and norm :: 'a => real.
  5268 
  5269 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  5270 reals into other types. The overloaded constant Reals :: 'a set is now
  5271 defined as range of_real; potential INCOMPATIBILITY.
  5272 
  5273 * Real: proper support for ML code generation, including 'quickcheck'.
  5274 Reals are implemented as arbitrary precision rationals.
  5275 
  5276 * Hyperreal: Several constants that previously worked only for the
  5277 reals have been generalized, so they now work over arbitrary vector
  5278 spaces. Type annotations may need to be added in some cases; potential
  5279 INCOMPATIBILITY.
  5280 
  5281   Infinitesimal  :: ('a::real_normed_vector) star set
  5282   HFinite        :: ('a::real_normed_vector) star set
  5283   HInfinite      :: ('a::real_normed_vector) star set
  5284   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5285   monad          :: ('a::real_normed_vector) star => 'a star set
  5286   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5287   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5288   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5289   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5290   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5291   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5292   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5293   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5294   sgn            :: 'a::real_normed_vector => 'a
  5295   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5296 
  5297 * Complex: Some complex-specific constants are now abbreviations for
  5298 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5299 hnorm.  Other constants have been entirely removed in favor of the
  5300 polymorphic versions (INCOMPATIBILITY):
  5301 
  5302   approx        <-- capprox
  5303   HFinite       <-- CFinite
  5304   HInfinite     <-- CInfinite
  5305   Infinitesimal <-- CInfinitesimal
  5306   monad         <-- cmonad
  5307   galaxy        <-- cgalaxy
  5308   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5309   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5310   (ns)deriv     <-- (ns)cderiv
  5311 
  5312 
  5313 *** HOL-Algebra ***
  5314 
  5315 * Formalisation of ideals and the quotient construction over rings.
  5316 
  5317 * Order and lattice theory no longer based on records.
  5318 INCOMPATIBILITY.
  5319 
  5320 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5321 greatest_closed.  INCOMPATIBILITY.
  5322 
  5323 * Method algebra is now set up via an attribute.  For examples see
  5324 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5325 of algebraic structures.
  5326 
  5327 * Renamed theory CRing to Ring.
  5328 
  5329 
  5330 *** HOL-Nominal ***
  5331 
  5332 * Substantial, yet incomplete support for nominal datatypes (binding
  5333 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5334 src/HOL/Nominal/Examples.  Prospective users should consult
  5335 http://isabelle.in.tum.de/nominal/
  5336 
  5337 
  5338 *** ML ***
  5339 
  5340 * ML basics: just one true type int, which coincides with IntInf.int
  5341 (even on SML/NJ).
  5342 
  5343 * ML within Isar: antiquotations allow to embed statically-checked
  5344 formal entities in the source, referring to the context available at
  5345 compile-time.  For example:
  5346 
  5347 ML {* @{sort "{zero,one}"} *}
  5348 ML {* @{typ "'a => 'b"} *}
  5349 ML {* @{term "%x. x"} *}
  5350 ML {* @{prop "x == y"} *}
  5351 ML {* @{ctyp "'a => 'b"} *}
  5352 ML {* @{cterm "%x. x"} *}
  5353 ML {* @{cprop "x == y"} *}
  5354 ML {* @{thm asm_rl} *}
  5355 ML {* @{thms asm_rl} *}
  5356 ML {* @{type_name c} *}
  5357 ML {* @{type_syntax c} *}
  5358 ML {* @{const_name c} *}
  5359 ML {* @{const_syntax c} *}
  5360 ML {* @{context} *}
  5361 ML {* @{theory} *}
  5362 ML {* @{theory Pure} *}
  5363 ML {* @{theory_ref} *}
  5364 ML {* @{theory_ref Pure} *}
  5365 ML {* @{simpset} *}
  5366 ML {* @{claset} *}
  5367 ML {* @{clasimpset} *}
  5368 
  5369 The same works for sources being ``used'' within an Isar context.
  5370 
  5371 * ML in Isar: improved error reporting; extra verbosity with
  5372 ML_Context.trace enabled.
  5373 
  5374 * Pure/General/table.ML: the join operations now works via exceptions
  5375 DUP/SAME instead of type option. This is simpler in simple cases, and
  5376 admits slightly more efficient complex applications.
  5377 
  5378 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5379 use Context.generic instead of just theory.
  5380 
  5381 * Pure: datatype Context.generic joins theory/Proof.context and
  5382 provides some facilities for code that works in either kind of
  5383 context, notably GenericDataFun for uniform theory and proof data.
  5384 
  5385 * Pure: simplified internal attribute type, which is now always
  5386 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5387 local (Proof.context) attributes have been discontinued, while
  5388 minimizing code duplication. Thm.rule_attribute and
  5389 Thm.declaration_attribute build canonical attributes; see also structure
  5390 Context for further operations on Context.generic, notably
  5391 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5392 declarations and definitions.
  5393 
  5394 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5395 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5396 init only required for impure data. INCOMPATIBILITY: empty really need
  5397 to be empty (no dependencies on theory content!)
  5398 
  5399 * Pure/kernel: consts certification ignores sort constraints given in
  5400 signature declarations. (This information is not relevant to the
  5401 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5402 potential INCOMPATIBILITY.
  5403 
  5404 * Pure: axiomatic type classes are now purely definitional, with
  5405 explicit proofs of class axioms and super class relations performed
  5406 internally. See Pure/axclass.ML for the main internal interfaces --
  5407 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5408 AxClass.axiomatize_class/classrel/arity supersede
  5409 Sign.add_classes/classrel/arities.
  5410 
  5411 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5412 global/local versions on theory vs. Proof.context have been
  5413 discontinued; Attrib.syntax and Method.syntax have been adapted
  5414 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5415 attributes, methods, etc.
  5416 
  5417 * Pure: several functions of signature "... -> theory -> theory * ..."
  5418 have been reoriented to "... -> theory -> ... * theory" in order to
  5419 allow natural usage in combination with the ||>, ||>>, |-> and
  5420 fold_map combinators.
  5421 
  5422 * Pure: official theorem names (closed derivations) and additional
  5423 comments (tags) are now strictly separate.  Name hints -- which are
  5424 maintained as tags -- may be attached any time without affecting the
  5425 derivation.
  5426 
  5427 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5428 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5429 achieve the old behaviour.
  5430 
  5431 * Pure: the "Goal" constant is now called "prop", supporting a
  5432 slightly more general idea of ``protecting'' meta-level rule
  5433 statements.
  5434 
  5435 * Pure: Logic.(un)varify only works in a global context, which is now
  5436 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5437 Logic.legacy_(un)varify as temporary workaround.
  5438 
  5439 * Pure: structure Name provides scalable operations for generating
  5440 internal variable names, notably Name.variants etc.  This replaces
  5441 some popular functions from term.ML:
  5442 
  5443   Term.variant		->  Name.variant
  5444   Term.variantlist	->  Name.variant_list
  5445   Term.invent_names	->  Name.invent_list
  5446 
  5447 Note that low-level renaming rarely occurs in new code -- operations
  5448 from structure Variable are used instead (see below).
  5449 
  5450 * Pure: structure Variable provides fundamental operations for proper
  5451 treatment of fixed/schematic variables in a context.  For example,
  5452 Variable.import introduces fixes for schematics of given facts and
  5453 Variable.export reverses the effect (up to renaming) -- this replaces
  5454 various freeze_thaw operations.
  5455 
  5456 * Pure: structure Goal provides simple interfaces for
  5457 init/conclude/finish and tactical prove operations (replacing former
  5458 Tactic.prove).  Goal.prove is the canonical way to prove results
  5459 within a given context; Goal.prove_global is a degraded version for
  5460 theory level goals, including a global Drule.standard.  Note that
  5461 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5462 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5463 in a locale context).
  5464 
  5465 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5466 and type checking (Syntax.check_term etc.), with common combinations
  5467 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5468 which are considered legacy and await removal.
  5469 
  5470 * Pure/Syntax: generic interfaces for type unchecking
  5471 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5472 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5473 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5474 available for convenience, but refer to the very same operations using
  5475 a mere theory instead of a full context.
  5476 
  5477 * Isar: simplified treatment of user-level errors, using exception
  5478 ERROR of string uniformly.  Function error now merely raises ERROR,
  5479 without any side effect on output channels.  The Isar toplevel takes
  5480 care of proper display of ERROR exceptions.  ML code may use plain
  5481 handle/can/try; cat_error may be used to concatenate errors like this:
  5482 
  5483   ... handle ERROR msg => cat_error msg "..."
  5484 
  5485 Toplevel ML code (run directly or through the Isar toplevel) may be
  5486 embedded into the Isar toplevel with exception display/debug like
  5487 this:
  5488 
  5489   Isar.toplevel (fn () => ...)
  5490 
  5491 INCOMPATIBILITY, removed special transform_error facilities, removed
  5492 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5493 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5494 -- use plain ERROR instead.
  5495 
  5496 * Isar: theory setup now has type (theory -> theory), instead of a
  5497 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5498 
  5499 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5500 ProofContext.debug/verbose flags.
  5501 
  5502 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5503 theory before entering a proof state.  Transactions now always see a
  5504 quasi-functional intermediate checkpoint, both in interactive and
  5505 batch mode.
  5506 
  5507 * Isar: simplified interfaces for outer syntax.  Renamed
  5508 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5509 OuterSyntax.add_parsers -- this functionality is now included in
  5510 OuterSyntax.command etc.  INCOMPATIBILITY.
  5511 
  5512 * Simplifier: the simpset of a running simplification process now
  5513 contains a proof context (cf. Simplifier.the_context), which is the
  5514 very context that the initial simpset has been retrieved from (by
  5515 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5516 (solver, looper etc.) may depend on arbitrary proof data.
  5517 
  5518 * Simplifier.inherit_context inherits the proof context (plus the
  5519 local bounds) of the current simplification process; any simproc
  5520 etc. that calls the Simplifier recursively should do this!  Removed
  5521 former Simplifier.inherit_bounds, which is already included here --
  5522 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5523 specify an explicit context using Simplifier.context/theory_context.
  5524 
  5525 * Simplifier/Classical Reasoner: more abstract interfaces
  5526 change_simpset/claset for modifying the simpset/claset reference of a
  5527 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5528 INCOMPATIBILITY.
  5529 
  5530 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5531 "Trueprop" etc.
  5532 
  5533 
  5534 *** System ***
  5535 
  5536 * settings: the default heap location within ISABELLE_HOME_USER now
  5537 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5538 Isabelle installations.
  5539 
  5540 * isabelle-process: option -S (secure mode) disables some critical
  5541 operations, notably runtime compilation and evaluation of ML source
  5542 code.
  5543 
  5544 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5545 
  5546 * Support for parallel execution, using native multicore support of
  5547 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5548 independent theories, according to the given theory header
  5549 specifications. The maximum number of worker threads is specified via
  5550 usedir option -M or the "max-threads" setting in Proof General. A
  5551 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5552 to 6 on a 8-core machine.  User-code needs to observe certain
  5553 guidelines for thread-safe programming, see appendix A in the Isar
  5554 Implementation manual.
  5555 
  5556 
  5557 
  5558 New in Isabelle2005 (October 2005)
  5559 ----------------------------------
  5560 
  5561 *** General ***
  5562 
  5563 * Theory headers: the new header syntax for Isar theories is
  5564 
  5565   theory <name>
  5566   imports <theory1> ... <theoryN>
  5567   uses <file1> ... <fileM>
  5568   begin
  5569 
  5570 where the 'uses' part is optional.  The previous syntax
  5571 
  5572   theory <name> = <theory1> + ... + <theoryN>:
  5573 
  5574 will disappear in the next release.  Use isatool fixheaders to convert
  5575 existing theory files.  Note that there is no change in ancient
  5576 non-Isar theories now, but these will disappear soon.
  5577 
  5578 * Theory loader: parent theories can now also be referred to via
  5579 relative and absolute paths.
  5580 
  5581 * Command 'find_theorems' searches for a list of criteria instead of a
  5582 list of constants. Known criteria are: intro, elim, dest, name:string,
  5583 simp:term, and any term. Criteria can be preceded by '-' to select
  5584 theorems that do not match. Intro, elim, dest select theorems that
  5585 match the current goal, name:s selects theorems whose fully qualified
  5586 name contain s, and simp:term selects all simplification rules whose
  5587 lhs match term.  Any other term is interpreted as pattern and selects
  5588 all theorems matching the pattern. Available in ProofGeneral under
  5589 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5590 
  5591   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5592 
  5593 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5594 matching the current goal as introduction rule and not having "HOL."
  5595 in their name (i.e. not being defined in theory HOL).
  5596 
  5597 * Command 'thms_containing' has been discontinued in favour of
  5598 'find_theorems'; INCOMPATIBILITY.
  5599 
  5600 * Communication with Proof General is now 8bit clean, which means that
  5601 Unicode text in UTF-8 encoding may be used within theory texts (both
  5602 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5603 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5604 
  5605   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5606   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5607 
  5608 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5609 Classical Reasoner.  Typical big applications run around 2 times
  5610 faster.
  5611 
  5612 
  5613 *** Document preparation ***
  5614 
  5615 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5616 of raw sources.  Only those symbols that do not require additional
  5617 LaTeX packages (depending on comments in isabellesym.sty) are
  5618 displayed properly, everything else is left verbatim.  isatool display
  5619 and isatool print are used as front ends (these are subject to the
  5620 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5621 
  5622 * Command tags control specific markup of certain regions of text,
  5623 notably folding and hiding.  Predefined tags include "theory" (for
  5624 theory begin and end), "proof" for proof commands, and "ML" for
  5625 commands involving ML code; the additional tags "visible" and
  5626 "invisible" are unused by default.  Users may give explicit tag
  5627 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5628 interpretation of tags is determined by the LaTeX job during document
  5629 preparation: see option -V of isatool usedir, or options -n and -t of
  5630 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5631 \isadroptag.
  5632 
  5633 Several document versions may be produced at the same time via isatool
  5634 usedir (the generated index.html will link all of them).  Typical
  5635 specifications include ''-V document=theory,proof,ML'' to present
  5636 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5637 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5638 these parts without any formal replacement text.  The Isabelle site
  5639 default settings produce ''document'' and ''outline'' versions as
  5640 specified above.
  5641 
  5642 * Several new antiquotations:
  5643 
  5644   @{term_type term} prints a term with its type annotated;
  5645 
  5646   @{typeof term} prints the type of a term;
  5647 
  5648   @{const const} is the same as @{term const}, but checks that the
  5649   argument is a known logical constant;
  5650 
  5651   @{term_style style term} and @{thm_style style thm} print a term or
  5652   theorem applying a "style" to it
  5653 
  5654   @{ML text}
  5655 
  5656 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5657 definitions, equations, inequations etc., 'concl' printing only the
  5658 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5659 to print the specified premise.  TermStyle.add_style provides an ML
  5660 interface for introducing further styles.  See also the "LaTeX Sugar"
  5661 document practical applications.  The ML antiquotation prints
  5662 type-checked ML expressions verbatim.
  5663 
  5664 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5665 and 'text' support optional locale specification '(in loc)', which
  5666 specifies the default context for interpreting antiquotations.  For
  5667 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5668 
  5669 * Option 'locale=NAME' of antiquotations specifies an alternative
  5670 context interpreting the subsequent argument.  For example: @{thm
  5671 [locale=lattice] inf_assoc}.
  5672 
  5673 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5674 a proof context.
  5675 
  5676 * Proper output of antiquotations for theory commands involving a
  5677 proof context (such as 'locale' or 'theorem (in loc) ...').
  5678 
  5679 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5680 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5681 
  5682 * isatool usedir: new option -C (default true) controls whether option
  5683 -D should include a copy of the original document directory; -C false
  5684 prevents unwanted effects such as copying of administrative CVS data.
  5685 
  5686 
  5687 *** Pure ***
  5688 
  5689 * Considerably improved version of 'constdefs' command.  Now performs
  5690 automatic type-inference of declared constants; additional support for
  5691 local structure declarations (cf. locales and HOL records), see also
  5692 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5693 sequential dependencies of definitions within a single 'constdefs'
  5694 section; moreover, the declared name needs to be an identifier.  If
  5695 all fails, consider to fall back on 'consts' and 'defs' separately.
  5696 
  5697 * Improved indexed syntax and implicit structures.  First of all,
  5698 indexed syntax provides a notational device for subscripted
  5699 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5700 expressions.  Secondly, in a local context with structure
  5701 declarations, number indexes \<^sub>n or the empty index (default
  5702 number 1) refer to a certain fixed variable implicitly; option
  5703 show_structs controls printing of implicit structures.  Typical
  5704 applications of these concepts involve record types and locales.
  5705 
  5706 * New command 'no_syntax' removes grammar declarations (and
  5707 translations) resulting from the given syntax specification, which is
  5708 interpreted in the same manner as for the 'syntax' command.
  5709 
  5710 * 'Advanced' translation functions (parse_translation etc.) may depend
  5711 on the signature of the theory context being presently used for
  5712 parsing/printing, see also isar-ref manual.
  5713 
  5714 * Improved 'oracle' command provides a type-safe interface to turn an
  5715 ML expression of type theory -> T -> term into a primitive rule of
  5716 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5717 is already included here); see also FOL/ex/IffExample.thy;
  5718 INCOMPATIBILITY.
  5719 
  5720 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5721 before); "cI" is no longer bound, use "c.intro" instead.
  5722 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5723 axclasses vs. locales.
  5724 
  5725 * Improved internal renaming of symbolic identifiers -- attach primes
  5726 instead of base 26 numbers.
  5727 
  5728 * New flag show_question_marks controls printing of leading question
  5729 marks in schematic variable names.
  5730 
  5731 * In schematic variable names, *any* symbol following \<^isub> or
  5732 \<^isup> is now treated as part of the base name.  For example, the
  5733 following works without printing of awkward ".0" indexes:
  5734 
  5735   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5736     by simp
  5737 
  5738 * Inner syntax includes (*(*nested*) comments*).
  5739 
  5740 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5741 annotations as "(00...)".
  5742 
  5743 * Clear separation of logical types and nonterminals, where the latter
  5744 may only occur in 'syntax' specifications or type abbreviations.
  5745 Before that distinction was only partially implemented via type class
  5746 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5747 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5748 exotic syntax specifications may require further adaption
  5749 (e.g. Cube/Cube.thy).
  5750 
  5751 * Removed obsolete type class "logic", use the top sort {} instead.
  5752 Note that non-logical types should be declared as 'nonterminals'
  5753 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5754 specifications.
  5755 
  5756 * Attributes 'induct' and 'cases': type or set names may now be
  5757 locally fixed variables as well.
  5758 
  5759 * Simplifier: can now control the depth to which conditional rewriting
  5760 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5761 Limit.
  5762 
  5763 * Simplifier: simplification procedures may now take the current
  5764 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5765 interface), which is very useful for calling the Simplifier
  5766 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5767 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5768 low-level mk_simproc no longer applies Logic.varify internally, to
  5769 allow for use in a context of fixed variables.
  5770 
  5771 * thin_tac now works even if the assumption being deleted contains !!
  5772 or ==>.  More generally, erule now works even if the major premise of
  5773 the elimination rule contains !! or ==>.
  5774 
  5775 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5776 
  5777 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5778 from Pure, which contains all common declarations already.  Both
  5779 theories are defined via plain Isabelle/Isar .thy files.
  5780 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5781 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5782 use isatool fixcpure to adapt your theory and ML sources.
  5783 
  5784 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5785 selections of theorems in named facts via index ranges.
  5786 
  5787 * 'print_theorems': in theory mode, really print the difference
  5788 wrt. the last state (works for interactive theory development only),
  5789 in proof mode print all local facts (cf. 'print_facts');
  5790 
  5791 * 'hide': option '(open)' hides only base names.
  5792 
  5793 * More efficient treatment of intermediate checkpoints in interactive
  5794 theory development.
  5795 
  5796 * Code generator is now invoked via code_module (incremental code
  5797 generation) and code_library (modular code generation, ML structures
  5798 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5799 must be quoted when used as identifiers.
  5800 
  5801 * New 'value' command for reading, evaluating and printing terms using
  5802 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5803 quoted when used as identifier.
  5804 
  5805 
  5806 *** Locales ***
  5807 
  5808 * New commands for the interpretation of locale expressions in
  5809 theories (1), locales (2) and proof contexts (3).  These generate
  5810 proof obligations from the expression specification.  After the
  5811 obligations have been discharged, theorems of the expression are added
  5812 to the theory, target locale or proof context.  The synopsis of the
  5813 commands is a follows:
  5814 
  5815   (1) interpretation expr inst
  5816   (2) interpretation target < expr
  5817   (3) interpret expr inst
  5818 
  5819 Interpretation in theories and proof contexts require a parameter
  5820 instantiation of terms from the current context.  This is applied to
  5821 specifications and theorems of the interpreted expression.
  5822 Interpretation in locales only permits parameter renaming through the
  5823 locale expression.  Interpretation is smart in that interpretations
  5824 that are active already do not occur in proof obligations, neither are
  5825 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5826 inspect active interpretations of a particular locale.  For details,
  5827 see the Isar Reference manual.  Examples can be found in
  5828 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5829 
  5830 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5831 'interpret' instead.
  5832 
  5833 * New context element 'constrains' for adding type constraints to
  5834 parameters.
  5835 
  5836 * Context expressions: renaming of parameters with syntax
  5837 redeclaration.
  5838 
  5839 * Locale declaration: 'includes' disallowed.
  5840 
  5841 * Proper static binding of attribute syntax -- i.e. types / terms /
  5842 facts mentioned as arguments are always those of the locale definition
  5843 context, independently of the context of later invocations.  Moreover,
  5844 locale operations (renaming and type / term instantiation) are applied
  5845 to attribute arguments as expected.
  5846 
  5847 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5848 actual attributes; rare situations may require Attrib.attribute to
  5849 embed those attributes into Attrib.src that lack concrete syntax.
  5850 Attribute implementations need to cooperate properly with the static
  5851 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5852 Attrib.XXX_thm etc. already do the right thing without further
  5853 intervention.  Only unusual applications -- such as "where" or "of"
  5854 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5855 on the context and the facts involved -- may have to assign parsed
  5856 values to argument tokens explicitly.
  5857 
  5858 * Changed parameter management in theorem generation for long goal
  5859 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5860 theorem statement in rare situations.
  5861 
  5862 * Locale inspection command 'print_locale' omits notes elements.  Use
  5863 'print_locale!' to have them included in the output.
  5864 
  5865 
  5866 *** Provers ***
  5867 
  5868 * Provers/hypsubst.ML: improved version of the subst method, for
  5869 single-step rewriting: it now works in bound variable contexts. New is
  5870 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5871 rewrite a different subterm than the original subst method, which is
  5872 still available as 'simplesubst'.
  5873 
  5874 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5875 and quasi orders.
  5876 
  5877 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5878 reflexive-transitive closure of relations.
  5879 
  5880 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5881 limit (previously hard-coded with a value of 20) user-definable.
  5882 
  5883 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5884 is peformed already.  Object-logics merely need to finish their
  5885 initial simpset configuration as before.  INCOMPATIBILITY.
  5886 
  5887 
  5888 *** HOL ***
  5889 
  5890 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5891 
  5892   syntax (epsilon)
  5893     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5894 
  5895 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5896 and x-symbol; use option '-m epsilon' to get it actually printed.
  5897 Moreover, the mathematically important symbolic identifier \<epsilon>
  5898 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5899 
  5900 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5901 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5902 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5903 support corresponding Isar calculations.
  5904 
  5905 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5906 instead of ":".
  5907 
  5908 * theory SetInterval: changed the syntax for open intervals:
  5909 
  5910   Old       New
  5911   {..n(}    {..<n}
  5912   {)n..}    {n<..}
  5913   {m..n(}   {m..<n}
  5914   {)m..n}   {m<..n}
  5915   {)m..n(}  {m<..<n}
  5916 
  5917 The old syntax is still supported but will disappear in the next
  5918 release.  For conversion use the following Emacs search and replace
  5919 patterns (these are not perfect but work quite well):
  5920 
  5921   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5922   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5923 
  5924 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5925 equalities in commutative rings; method 'algebra' provides a generic
  5926 interface.
  5927 
  5928 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5929 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5930 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5931 be a tuple pattern.
  5932 
  5933 Some new syntax forms are available:
  5934 
  5935   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5936   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5937   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5938   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5939 
  5940 The latter form "\<Sum>x < k. e" used to be based on a separate
  5941 function "Summation", which has been discontinued.
  5942 
  5943 * theory Finite_Set: in structured induction proofs, the insert case
  5944 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5945 (insert F x)'.
  5946 
  5947 * The 'refute' command has been extended to support a much larger
  5948 fragment of HOL, including axiomatic type classes, constdefs and
  5949 typedefs, inductive datatypes and recursion.
  5950 
  5951 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5952 Requires zChaff with proof generation to be installed.  See
  5953 HOL/ex/SAT_Examples.thy for examples.
  5954 
  5955 * Datatype induction via method 'induct' now preserves the name of the
  5956 induction variable. For example, when proving P(xs::'a list) by
  5957 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5958 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5959 in unstructured proof scripts.
  5960 
  5961 * Reworked implementation of records.  Improved scalability for
  5962 records with many fields, avoiding performance problems for type
  5963 inference. Records are no longer composed of nested field types, but
  5964 of nested extension types. Therefore the record type only grows linear
  5965 in the number of extensions and not in the number of fields.  The
  5966 top-level (users) view on records is preserved.  Potential
  5967 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5968 old record representation. The type generated for a record is called
  5969 <record_name>_ext_type.
  5970 
  5971 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5972 proofs triggered by a record definition or a simproc (if
  5973 quick_and_dirty is enabled).  Definitions of large records can take
  5974 quite long.
  5975 
  5976 New simproc record_upd_simproc for simplification of multiple record
  5977 updates enabled by default.  Moreover, trivial updates are also
  5978 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5979 occasionally, since simplification is more powerful by default.
  5980 
  5981 * typedef: proper support for polymorphic sets, which contain extra
  5982 type-variables in the term.
  5983 
  5984 * Simplifier: automatically reasons about transitivity chains
  5985 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5986 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5987 old proofs break occasionally as simplification may now solve more
  5988 goals than previously.
  5989 
  5990 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5991 present.  Works for all partial orders (class "order"), in particular
  5992 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5993 just like y <= x.
  5994 
  5995 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5996 bound variable or a constant then the let is unfolded.  Otherwise
  5997 first a is simplified to b, and then f b is simplified to g. If
  5998 possible we abstract b from g arriving at "let x = b in h x",
  5999 otherwise we unfold the let and arrive at g.  The simproc can be
  6000 enabled/disabled by the reference use_let_simproc.  Potential
  6001 INCOMPATIBILITY since simplification is more powerful by default.
  6002 
  6003 * Classical reasoning: the meson method now accepts theorems as arguments.
  6004 
  6005 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  6006 jobs to provide advice on the provability of subgoals.
  6007 
  6008 * Theory OrderedGroup and Ring_and_Field: various additions and
  6009 improvements to faciliate calculations involving equalities and
  6010 inequalities.
  6011 
  6012 The following theorems have been eliminated or modified
  6013 (INCOMPATIBILITY):
  6014 
  6015   abs_eq             now named abs_of_nonneg
  6016   abs_of_ge_0        now named abs_of_nonneg
  6017   abs_minus_eq       now named abs_of_nonpos
  6018   imp_abs_id         now named abs_of_nonneg
  6019   imp_abs_neg_id     now named abs_of_nonpos
  6020   mult_pos           now named mult_pos_pos
  6021   mult_pos_le        now named mult_nonneg_nonneg
  6022   mult_pos_neg_le    now named mult_nonneg_nonpos
  6023   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  6024   mult_neg           now named mult_neg_neg
  6025   mult_neg_le        now named mult_nonpos_nonpos
  6026 
  6027 * The following lemmas in Ring_and_Field have been added to the simplifier:
  6028      
  6029      zero_le_square
  6030      not_square_less_zero 
  6031 
  6032   The following lemmas have been deleted from Real/RealPow:
  6033   
  6034      realpow_zero_zero
  6035      realpow_two
  6036      realpow_less
  6037      zero_le_power
  6038      realpow_two_le
  6039      abs_realpow_two
  6040      realpow_two_abs     
  6041 
  6042 * Theory Parity: added rules for simplifying exponents.
  6043 
  6044 * Theory List:
  6045 
  6046 The following theorems have been eliminated or modified
  6047 (INCOMPATIBILITY):
  6048 
  6049   list_all_Nil       now named list_all.simps(1)
  6050   list_all_Cons      now named list_all.simps(2)
  6051   list_all_conv      now named list_all_iff
  6052   set_mem_eq         now named mem_iff
  6053 
  6054 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  6055 asymptotic "big O" calculations.  See the notes in BigO.thy.
  6056 
  6057 
  6058 *** HOL-Complex ***
  6059 
  6060 * Theory RealDef: better support for embedding natural numbers and
  6061 integers in the reals.
  6062 
  6063 The following theorems have been eliminated or modified
  6064 (INCOMPATIBILITY):
  6065 
  6066   exp_ge_add_one_self  now requires no hypotheses
  6067   real_of_int_add      reversed direction of equality (use [symmetric])
  6068   real_of_int_minus    reversed direction of equality (use [symmetric])
  6069   real_of_int_diff     reversed direction of equality (use [symmetric])
  6070   real_of_int_mult     reversed direction of equality (use [symmetric])
  6071 
  6072 * Theory RComplete: expanded support for floor and ceiling functions.
  6073 
  6074 * Theory Ln is new, with properties of the natural logarithm
  6075 
  6076 * Hyperreal: There is a new type constructor "star" for making
  6077 nonstandard types.  The old type names are now type synonyms:
  6078 
  6079   hypreal = real star
  6080   hypnat = nat star
  6081   hcomplex = complex star
  6082 
  6083 * Hyperreal: Many groups of similarly-defined constants have been
  6084 replaced by polymorphic versions (INCOMPATIBILITY):
  6085 
  6086   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  6087 
  6088   starset      <-- starsetNat, starsetC
  6089   *s*          <-- *sNat*, *sc*
  6090   starset_n    <-- starsetNat_n, starsetC_n
  6091   *sn*         <-- *sNatn*, *scn*
  6092   InternalSets <-- InternalNatSets, InternalCSets
  6093 
  6094   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  6095   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  6096   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  6097   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  6098   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  6099 
  6100 * Hyperreal: Many type-specific theorems have been removed in favor of
  6101 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  6102 
  6103   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  6104   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  6105   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  6106   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  6107   right_minus <-- hypreal_add_minus
  6108   left_minus <-- {hypreal,hcomplex}_add_minus_left
  6109   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  6110   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  6111   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  6112   mult_1_right <-- hcomplex_mult_one_right
  6113   mult_zero_left <-- hcomplex_mult_zero_left
  6114   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  6115   right_distrib <-- hypnat_add_mult_distrib2
  6116   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  6117   right_inverse <-- hypreal_mult_inverse
  6118   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  6119   order_refl <-- {hypreal,hypnat}_le_refl
  6120   order_trans <-- {hypreal,hypnat}_le_trans
  6121   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  6122   order_less_le <-- {hypreal,hypnat}_less_le
  6123   linorder_linear <-- {hypreal,hypnat}_le_linear
  6124   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  6125   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  6126   add_nonneg_nonneg <-- hypreal_le_add_order
  6127 
  6128 * Hyperreal: Separate theorems having to do with type-specific
  6129 versions of constants have been merged into theorems that apply to the
  6130 new polymorphic constants (INCOMPATIBILITY):
  6131 
  6132   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  6133   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  6134   STAR_Un <-- {STAR,NatStar,STARC}_Un
  6135   STAR_Int <-- {STAR,NatStar,STARC}_Int
  6136   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  6137   STAR_subset <-- {STAR,NatStar,STARC}_subset
  6138   STAR_mem <-- {STAR,NatStar,STARC}_mem
  6139   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  6140   STAR_diff <-- {STAR,STARC}_diff
  6141   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  6142     STARC_hcomplex_of_complex}_image_subset
  6143   starset_n_Un <-- starset{Nat,C}_n_Un
  6144   starset_n_Int <-- starset{Nat,C}_n_Int
  6145   starset_n_Compl <-- starset{Nat,C}_n_Compl
  6146   starset_n_diff <-- starset{Nat,C}_n_diff
  6147   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  6148   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  6149   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  6150   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  6151   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  6152   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  6153   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  6154   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  6155   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  6156   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  6157   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  6158   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  6159   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  6160   starfun_diff <-- starfun{C,RC,CR}_diff
  6161   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  6162   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  6163   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  6164   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  6165   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  6166   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  6167   starfun_Id <-- starfunC_Id
  6168   starfun_approx <-- starfun{Nat,CR}_approx
  6169   starfun_capprox <-- starfun{C,RC}_capprox
  6170   starfun_abs <-- starfunNat_rabs
  6171   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  6172   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  6173   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  6174   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  6175   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  6176   starfun_add_approx <-- starfunCR_add_approx
  6177   starfun_inverse_inverse <-- starfunC_inverse_inverse
  6178   starfun_divide <-- starfun{C,CR,RC}_divide
  6179   starfun_n <-- starfun{Nat,C}_n
  6180   starfun_n_mult <-- starfun{Nat,C}_n_mult
  6181   starfun_n_add <-- starfun{Nat,C}_n_add
  6182   starfun_n_add_minus <-- starfunNat_n_add_minus
  6183   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  6184   starfun_n_minus <-- starfun{Nat,C}_n_minus
  6185   starfun_n_eq <-- starfun{Nat,C}_n_eq
  6186 
  6187   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  6188   star_n_minus <-- {hypreal,hcomplex}_minus
  6189   star_n_diff <-- {hypreal,hcomplex}_diff
  6190   star_n_mult <-- {hypreal,hcomplex}_mult
  6191   star_n_inverse <-- {hypreal,hcomplex}_inverse
  6192   star_n_le <-- {hypreal,hypnat}_le
  6193   star_n_less <-- {hypreal,hypnat}_less
  6194   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  6195   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  6196   star_n_abs <-- hypreal_hrabs
  6197   star_n_divide <-- hcomplex_divide
  6198 
  6199   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  6200   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  6201   star_of_diff <-- hypreal_of_real_diff
  6202   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  6203   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  6204   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  6205   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  6206   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  6207   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  6208   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  6209   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  6210   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  6211   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  6212   star_of_number_of <-- {hypreal,hcomplex}_number_of
  6213   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  6214   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  6215   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  6216   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  6217   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  6218   star_of_power <-- hypreal_of_real_power
  6219   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  6220 
  6221 * Hyperreal: new method "transfer" that implements the transfer
  6222 principle of nonstandard analysis. With a subgoal that mentions
  6223 nonstandard types like "'a star", the command "apply transfer"
  6224 replaces it with an equivalent one that mentions only standard types.
  6225 To be successful, all free variables must have standard types; non-
  6226 standard variables must have explicit universal quantifiers.
  6227 
  6228 * Hyperreal: A theory of Taylor series.
  6229 
  6230 
  6231 *** HOLCF ***
  6232 
  6233 * Discontinued special version of 'constdefs' (which used to support
  6234 continuous functions) in favor of the general Pure one with full
  6235 type-inference.
  6236 
  6237 * New simplification procedure for solving continuity conditions; it
  6238 is much faster on terms with many nested lambda abstractions (cubic
  6239 instead of exponential time).
  6240 
  6241 * New syntax for domain package: selector names are now optional.
  6242 Parentheses should be omitted unless argument is lazy, for example:
  6243 
  6244   domain 'a stream = cons "'a" (lazy "'a stream")
  6245 
  6246 * New command 'fixrec' for defining recursive functions with pattern
  6247 matching; defining multiple functions with mutual recursion is also
  6248 supported.  Patterns may include the constants cpair, spair, up, sinl,
  6249 sinr, or any data constructor defined by the domain package. The given
  6250 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  6251 syntax and examples.
  6252 
  6253 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  6254 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  6255 but the proof obligation additionally includes an admissibility
  6256 requirement. The packages generate instances of class cpo or pcpo,
  6257 with continuity and strictness theorems for Rep and Abs.
  6258 
  6259 * HOLCF: Many theorems have been renamed according to a more standard naming
  6260 scheme (INCOMPATIBILITY):
  6261 
  6262   foo_inject:  "foo$x = foo$y ==> x = y"
  6263   foo_eq:      "(foo$x = foo$y) = (x = y)"
  6264   foo_less:    "(foo$x << foo$y) = (x << y)"
  6265   foo_strict:  "foo$UU = UU"
  6266   foo_defined: "... ==> foo$x ~= UU"
  6267   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  6268 
  6269 
  6270 *** ZF ***
  6271 
  6272 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  6273 including the First Isomorphism Theorem (on quotienting by the kernel
  6274 of a homomorphism).
  6275 
  6276 * ZF/Simplifier: install second copy of type solver that actually
  6277 makes use of TC rules declared to Isar proof contexts (or locales);
  6278 the old version is still required for ML proof scripts.
  6279 
  6280 
  6281 *** Cube ***
  6282 
  6283 * Converted to Isar theory format; use locales instead of axiomatic
  6284 theories.
  6285 
  6286 
  6287 *** ML ***
  6288 
  6289 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6290 for ||>, ||>>, |>>,
  6291 
  6292 * Pure/library.ML no longer defines its own option datatype, but uses
  6293 that of the SML basis, which has constructors NONE and SOME instead of
  6294 None and Some, as well as exception Option.Option instead of OPTION.
  6295 The functions the, if_none, is_some, is_none have been adapted
  6296 accordingly, while Option.map replaces apsome.
  6297 
  6298 * Pure/library.ML: the exception LIST has been given up in favour of
  6299 the standard exceptions Empty and Subscript, as well as
  6300 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6301 superceded by the standard hd and tl functions etc.
  6302 
  6303 A number of basic list functions are no longer exported to the ML
  6304 toplevel, as they are variants of predefined functions.  The following
  6305 suggests how one can translate existing code:
  6306 
  6307     rev_append xs ys = List.revAppend (xs, ys)
  6308     nth_elem (i, xs) = List.nth (xs, i)
  6309     last_elem xs = List.last xs
  6310     flat xss = List.concat xss
  6311     seq fs = List.app fs
  6312     partition P xs = List.partition P xs
  6313     mapfilter f xs = List.mapPartial f xs
  6314 
  6315 * Pure/library.ML: several combinators for linear functional
  6316 transformations, notably reverse application and composition:
  6317 
  6318   x |> f                f #> g
  6319   (x, y) |-> f          f #-> g
  6320 
  6321 * Pure/library.ML: introduced/changed precedence of infix operators:
  6322 
  6323   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6324   infix 2 ?;
  6325   infix 3 o oo ooo oooo;
  6326   infix 4 ~~ upto downto;
  6327 
  6328 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6329 infix operators.
  6330 
  6331 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6332 fold_map support linear functional transformations and nesting.  For
  6333 example:
  6334 
  6335   fold f [x1, ..., xN] y =
  6336     y |> f x1 |> ... |> f xN
  6337 
  6338   (fold o fold) f [xs1, ..., xsN] y =
  6339     y |> fold f xs1 |> ... |> fold f xsN
  6340 
  6341   fold f [x1, ..., xN] =
  6342     f x1 #> ... #> f xN
  6343 
  6344   (fold o fold) f [xs1, ..., xsN] =
  6345     fold f xs1 #> ... #> fold f xsN
  6346 
  6347 * Pure/library.ML: the following selectors on type 'a option are
  6348 available:
  6349 
  6350   the:               'a option -> 'a  (*partial*)
  6351   these:             'a option -> 'a  where 'a = 'b list
  6352   the_default: 'a -> 'a option -> 'a
  6353   the_list:          'a option -> 'a list
  6354 
  6355 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6356 basic operations for association lists, following natural argument
  6357 order; moreover the explicit equality predicate passed here avoids
  6358 potentially expensive polymorphic runtime equality checks.
  6359 The old functions may be expressed as follows:
  6360 
  6361   assoc = uncurry (AList.lookup (op =))
  6362   assocs = these oo AList.lookup (op =)
  6363   overwrite = uncurry (AList.update (op =)) o swap
  6364 
  6365 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6366 
  6367   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6368   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6369 
  6370 replacing make_keylist and keyfilter (occassionally used)
  6371 Naive rewrites:
  6372 
  6373   make_keylist = AList.make
  6374   keyfilter = AList.find (op =)
  6375 
  6376 * eq_fst and eq_snd now take explicit equality parameter, thus
  6377   avoiding eqtypes. Naive rewrites:
  6378 
  6379     eq_fst = eq_fst (op =)
  6380     eq_snd = eq_snd (op =)
  6381 
  6382 * Removed deprecated apl and apr (rarely used).
  6383   Naive rewrites:
  6384 
  6385     apl (n, op) =>>= curry op n
  6386     apr (op, m) =>>= fn n => op (n, m)
  6387 
  6388 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6389 provides a reasonably efficient light-weight implementation of sets as
  6390 lists.
  6391 
  6392 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6393 few new operations; existing lookup and update are now curried to
  6394 follow natural argument order (for use with fold etc.);
  6395 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6396 
  6397 * Pure/General: output via the Isabelle channels of
  6398 writeln/warning/error etc. is now passed through Output.output, with a
  6399 hook for arbitrary transformations depending on the print_mode
  6400 (cf. Output.add_mode -- the first active mode that provides a output
  6401 function wins).  Already formatted output may be embedded into further
  6402 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6403 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6404 accommodate easy composition of diagnostic messages etc.  Programmers
  6405 rarely need to care about Output.output or Output.raw at all, with
  6406 some notable exceptions: Output.output is required when bypassing the
  6407 standard channels (writeln etc.), or in token translations to produce
  6408 properly formatted results; Output.raw is required when capturing
  6409 already output material that will eventually be presented to the user
  6410 a second time.  For the default print mode, both Output.output and
  6411 Output.raw have no effect.
  6412 
  6413 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6414 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6415 cumulative results are displayed at the end of a batch session.
  6416 
  6417 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6418 replaced by File.platform_path and File.shell_path (with appropriate
  6419 hooks).  This provides a clean interface for unusual systems where the
  6420 internal and external process view of file names are different.
  6421 
  6422 * Pure: more efficient orders for basic syntactic entities: added
  6423 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6424 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6425 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6426 orders now -- potential INCOMPATIBILITY for code that depends on a
  6427 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6428 Library.sort_strings on result).
  6429 
  6430 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6431 fold_types traverse types/terms from left to right, observing natural
  6432 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6433 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6434 
  6435 * Pure: name spaces have been refined, with significant changes of the
  6436 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6437 to extern(_table).  The plain name entry path is superceded by a
  6438 general 'naming' context, which also includes the 'policy' to produce
  6439 a fully qualified name and external accesses of a fully qualified
  6440 name; NameSpace.extend is superceded by context dependent
  6441 Sign.declare_name.  Several theory and proof context operations modify
  6442 the naming context.  Especially note Theory.restore_naming and
  6443 ProofContext.restore_naming to get back to a sane state; note that
  6444 Theory.add_path is no longer sufficient to recover from
  6445 Theory.absolute_path in particular.
  6446 
  6447 * Pure: new flags short_names (default false) and unique_names
  6448 (default true) for controlling output of qualified names.  If
  6449 short_names is set, names are printed unqualified.  If unique_names is
  6450 reset, the name prefix is reduced to the minimum required to achieve
  6451 the original result when interning again, even if there is an overlap
  6452 with earlier declarations.
  6453 
  6454 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6455 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6456 (useful for printing error messages).  INCOMPATIBILITY.
  6457 
  6458 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6459 Theory.theory are now identified, referring to the universal
  6460 Context.theory (see Pure/context.ML).  Actual signature and theory
  6461 content is managed as theory data.  The old code and interfaces were
  6462 spread over many files and structures; the new arrangement introduces
  6463 considerable INCOMPATIBILITY to gain more clarity:
  6464 
  6465   Context -- theory management operations (name, identity, inclusion,
  6466     parents, ancestors, merge, etc.), plus generic theory data;
  6467 
  6468   Sign -- logical signature and syntax operations (declaring consts,
  6469     types, etc.), plus certify/read for common entities;
  6470 
  6471   Theory -- logical theory operations (stating axioms, definitions,
  6472     oracles), plus a copy of logical signature operations (consts,
  6473     types, etc.); also a few basic management operations (Theory.copy,
  6474     Theory.merge, etc.)
  6475 
  6476 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6477 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6478 for convenience -- they merely return the theory.
  6479 
  6480 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6481 
  6482 * Pure: the Isar proof context type is already defined early in Pure
  6483 as Context.proof (note that ProofContext.context and Proof.context are
  6484 aliases, where the latter is the preferred name).  This enables other
  6485 Isabelle components to refer to that type even before Isar is present.
  6486 
  6487 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6488 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6489 any of these kinds.  For example, Sign.intern typeK is now
  6490 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6491 Theory.hide_types.  Also note that former
  6492 Theory.hide_classes/types/consts are now
  6493 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6494 internalize their arguments!  INCOMPATIBILITY.
  6495 
  6496 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6497 datatype thmref (with constructors Name and NameSelection) instead of
  6498 plain string -- INCOMPATIBILITY;
  6499 
  6500 * Pure: cases produced by proof methods specify options, where NONE
  6501 means to remove case bindings -- INCOMPATIBILITY in
  6502 (RAW_)METHOD_CASES.
  6503 
  6504 * Pure: the following operations retrieve axioms or theorems from a
  6505 theory node or theory hierarchy, respectively:
  6506 
  6507   Theory.axioms_of: theory -> (string * term) list
  6508   Theory.all_axioms_of: theory -> (string * term) list
  6509   PureThy.thms_of: theory -> (string * thm) list
  6510   PureThy.all_thms_of: theory -> (string * thm) list
  6511 
  6512 * Pure: print_tac now outputs the goal through the trace channel.
  6513 
  6514 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6515 Reference Toplevel.debug (default false) controls detailed printing
  6516 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6517 controls execution profiling -- set to 1 for time and 2 for space
  6518 (both increase the runtime).
  6519 
  6520 * Isar session: The initial use of ROOT.ML is now always timed,
  6521 i.e. the log will show the actual process times, in contrast to the
  6522 elapsed wall-clock time that the outer shell wrapper produces.
  6523 
  6524 * Simplifier: improved handling of bound variables (nameless
  6525 representation, avoid allocating new strings).  Simprocs that invoke
  6526 the Simplifier recursively should use Simplifier.inherit_bounds to
  6527 avoid local name clashes.  Failure to do so produces warnings
  6528 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6529 for further details.
  6530 
  6531 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6532 bindings for all theorems stored within a given theory; this may help
  6533 in porting non-Isar theories to Isar ones, while keeping ML proof
  6534 scripts for the time being.
  6535 
  6536 * ML operator HTML.with_charset specifies the charset begin used for
  6537 generated HTML files.  For example:
  6538 
  6539   HTML.with_charset "utf-8" use_thy "Hebrew";
  6540   HTML.with_charset "utf-8" use_thy "Chinese";
  6541 
  6542 
  6543 *** System ***
  6544 
  6545 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6546 isabelle, isatool etc.).
  6547 
  6548 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6549 isatool doc, isatool mkdir, display_drafts etc.).
  6550 
  6551 * isatool usedir: option -f allows specification of the ML file to be
  6552 used by Isabelle; default is ROOT.ML.
  6553 
  6554 * New isatool version outputs the version identifier of the Isabelle
  6555 distribution being used.
  6556 
  6557 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6558 (containing Boolean satisfiability problems) into Isabelle/HOL
  6559 theories.
  6560 
  6561 
  6562 
  6563 New in Isabelle2004 (April 2004)
  6564 --------------------------------
  6565 
  6566 *** General ***
  6567 
  6568 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6569   Replaces linorder.ML.
  6570 
  6571 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6572   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6573   (\<a>...\<z>), are now considered normal letters, and can therefore
  6574   be used anywhere where an ASCII letter (a...zA...Z) has until
  6575   now. COMPATIBILITY: This obviously changes the parsing of some
  6576   terms, especially where a symbol has been used as a binder, say
  6577   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6578   as an identifier.  Fix it by inserting a space around former
  6579   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6580   existing theory and ML files.
  6581 
  6582 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6583 
  6584 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6585   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6586   a normal (but invisible) letter. For multiple letter subscripts repeat
  6587   \<^isub> like this: x\<^isub>1\<^isub>2.
  6588 
  6589 * Pure: There are now sub-/superscripts that can span more than one
  6590   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6591   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6592   superscript. The new control characters are not identifier parts.
  6593 
  6594 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6595   content of "..." to the latex file instead of \isacntrl... . The "..."
  6596   may consist of any printable characters excluding the end bracket >.
  6597 
  6598 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6599   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6600   declare constants "final", which prevents their being given a definition
  6601   later.  It is useful for constants whose behaviour is fixed axiomatically
  6602   rather than definitionally, such as the meta-logic connectives.
  6603 
  6604 * Pure: 'instance' now handles general arities with general sorts
  6605   (i.e. intersections of classes),
  6606 
  6607 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6608   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6609   It can be changed to alter the colors/layout of generated pages.
  6610 
  6611 
  6612 *** Isar ***
  6613 
  6614 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6615   cut_tac, subgoal_tac and thin_tac:
  6616   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6617     locales are no longer forced to write Isar proof scripts.
  6618     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6619     emulations.
  6620   - INCOMPATIBILITY: names of variables to be instantiated may no
  6621     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6622     This is consistent with the instantiation attribute "where".
  6623 
  6624 * Attributes "where" and "of":
  6625   - Now take type variables of instantiated theorem into account when reading
  6626     the instantiation string.  This fixes a bug that caused instantiated
  6627     theorems to have too special types in some circumstances.
  6628   - "where" permits explicit instantiations of type variables.
  6629 
  6630 * Calculation commands "moreover" and "also" no longer interfere with
  6631   current facts ("this"), admitting arbitrary combinations with "then"
  6632   and derived forms.
  6633 
  6634 * Locales:
  6635   - Goal statements involving the context element "includes" no longer
  6636     generate theorems with internal delta predicates (those ending on
  6637     "_axioms") in the premise.
  6638     Resolve particular premise with <locale>.intro to obtain old form.
  6639   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6640     specification and "includes" elements in goal statement.
  6641   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6642     [intro?] and [elim?] (respectively) by default.
  6643   - Experimental command for instantiation of locales in proof contexts:
  6644         instantiate <label>[<attrs>]: <loc>
  6645     Instantiates locale <loc> and adds all its theorems to the current context
  6646     taking into account their attributes.  Label and attrs are optional
  6647     modifiers, like in theorem declarations.  If present, names of
  6648     instantiated theorems are qualified with <label>, and the attributes
  6649     <attrs> are applied after any attributes these theorems might have already.
  6650       If the locale has assumptions, a chained fact of the form
  6651     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6652     are derived.  The command does not support old-style locales declared
  6653     with "locale (open)".
  6654       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6655 
  6656 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6657   (Isar) contexts.
  6658 
  6659 
  6660 *** HOL ***
  6661 
  6662 * Proof import: new image HOL4 contains the imported library from
  6663   the HOL4 system with about 2500 theorems. It is imported by
  6664   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6665   can be used like any other Isabelle image.  See
  6666   HOL/Import/HOL/README for more information.
  6667 
  6668 * Simplifier:
  6669   - Much improved handling of linear and partial orders.
  6670     Reasoners for linear and partial orders are set up for type classes
  6671     "linorder" and "order" respectively, and are added to the default simpset
  6672     as solvers.  This means that the simplifier can build transitivity chains
  6673     to solve goals from the assumptions.
  6674   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6675     of blast or auto after simplification become unnecessary because the goal
  6676     is solved by simplification already.
  6677 
  6678 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6679     all proved in axiomatic type classes for semirings, rings and fields.
  6680 
  6681 * Numerics:
  6682   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6683     now formalized using the Ring_and_Field theory mentioned above.
  6684   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6685     than before, because now they are set up once in a generic manner.
  6686   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6687     Look for the general versions in Ring_and_Field (and Power if they concern
  6688     exponentiation).
  6689 
  6690 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6691 
  6692 * Records:
  6693   - Record types are now by default printed with their type abbreviation
  6694     instead of the list of all field types. This can be configured via
  6695     the reference "print_record_type_abbr".
  6696   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6697     (not enabled by default).
  6698   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6699     EX x. x = sel r to True (not enabled by default).
  6700   - Tactic "record_split_simp_tac" to split and simplify records added.
  6701 
  6702 * 'specification' command added, allowing for definition by
  6703   specification.  There is also an 'ax_specification' command that
  6704   introduces the new constants axiomatically.
  6705 
  6706 * arith(_tac) is now able to generate counterexamples for reals as well.
  6707 
  6708 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6709 
  6710 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6711   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6712 
  6713 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6714   matrix theory to linear programming.
  6715 
  6716 * Unions and Intersections:
  6717   The latex output syntax of UN and INT has been changed
  6718   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6719   i.e. the index formulae has become a subscript.
  6720   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6721 
  6722 * Unions and Intersections over Intervals:
  6723   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6724   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6725   like in normal math, and corresponding versions for < and for intersection.
  6726 
  6727 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6728   lexicographic dictonary ordering has been added as "lexord".
  6729 
  6730 * ML: the legacy theory structures Int and List have been removed. They had
  6731   conflicted with ML Basis Library structures having the same names.
  6732 
  6733 * 'refute' command added to search for (finite) countermodels.  Only works
  6734   for a fragment of HOL.  The installation of an external SAT solver is
  6735   highly recommended.  See "HOL/Refute.thy" for details.
  6736 
  6737 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6738   formulae under an assignment of free variables to random values.
  6739   In contrast to 'refute', it can deal with inductive datatypes,
  6740   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6741   for examples.
  6742 
  6743 
  6744 *** HOLCF ***
  6745 
  6746 * Streams now come with concatenation and are part of the HOLCF image
  6747 
  6748 
  6749 
  6750 New in Isabelle2003 (May 2003)
  6751 ------------------------------
  6752 
  6753 *** General ***
  6754 
  6755 * Provers/simplifier:
  6756 
  6757   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6758     Assumptions are now subject to complete mutual simplification,
  6759     not just from left to right. The simplifier now preserves
  6760     the order of assumptions.
  6761 
  6762     Potential INCOMPATIBILITY:
  6763 
  6764     -- simp sometimes diverges where the old version did
  6765        not, e.g. invoking simp on the goal
  6766 
  6767         [| P (f x); y = x; f x = f y |] ==> Q
  6768 
  6769        now gives rise to the infinite reduction sequence
  6770 
  6771         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6772 
  6773        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6774        kind of problem.
  6775 
  6776     -- Tactics combining classical reasoner and simplification (such as auto)
  6777        are also affected by this change, because many of them rely on
  6778        simp. They may sometimes diverge as well or yield a different numbers
  6779        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6780        in case of problems. Sometimes subsequent calls to the classical
  6781        reasoner will fail because a preceeding call to the simplifier too
  6782        eagerly simplified the goal, e.g. deleted redundant premises.
  6783 
  6784   - The simplifier trace now shows the names of the applied rewrite rules
  6785 
  6786   - You can limit the number of recursive invocations of the simplifier
  6787     during conditional rewriting (where the simplifie tries to solve the
  6788     conditions before applying the rewrite rule):
  6789     ML "simp_depth_limit := n"
  6790     where n is an integer. Thus you can force termination where previously
  6791     the simplifier would diverge.
  6792 
  6793   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6794 
  6795   - No longer aborts on failed congruence proof.  Instead, the
  6796     congruence is ignored.
  6797 
  6798 * Pure: New generic framework for extracting programs from constructive
  6799   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6800   as HOL/Extraction for some case studies.
  6801 
  6802 * Pure: The main goal of the proof state is no longer shown by default, only
  6803 the subgoals. This behaviour is controlled by a new flag.
  6804    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6805 (ML: Proof.show_main_goal).
  6806 
  6807 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6808 rules whose conclusion matches subgoal 1:
  6809       PG menu: Isabelle/Isar -> Show me -> matching rules
  6810 The rules are ordered by how closely they match the subgoal.
  6811 In particular, rules that solve a subgoal outright are displayed first
  6812 (or rather last, the way they are printed).
  6813 (ML: ProofGeneral.print_intros())
  6814 
  6815 * Pure: New flag trace_unify_fail causes unification to print
  6816 diagnostic information (PG: in trace buffer) when it fails. This is
  6817 useful for figuring out why single step proofs like rule, erule or
  6818 assumption failed.
  6819 
  6820 * Pure: Locale specifications now produce predicate definitions
  6821 according to the body of text (covering assumptions modulo local
  6822 definitions); predicate "loc_axioms" covers newly introduced text,
  6823 while "loc" is cumulative wrt. all included locale expressions; the
  6824 latter view is presented only on export into the global theory
  6825 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6826 on the old view without predicates;
  6827 
  6828 * Pure: predefined locales "var" and "struct" are useful for sharing
  6829 parameters (as in CASL, for example); just specify something like
  6830 ``var x + var y + struct M'' as import;
  6831 
  6832 * Pure: improved thms_containing: proper indexing of facts instead of
  6833 raw theorems; check validity of results wrt. current name space;
  6834 include local facts of proof configuration (also covers active
  6835 locales), cover fixed variables in index; may use "_" in term
  6836 specification; an optional limit for the number of printed facts may
  6837 be given (the default is 40);
  6838 
  6839 * Pure: disallow duplicate fact bindings within new-style theory files
  6840 (batch-mode only);
  6841 
  6842 * Provers: improved induct method: assumptions introduced by case
  6843 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6844 the goal statement); "foo" still refers to all facts collectively;
  6845 
  6846 * Provers: the function blast.overloaded has been removed: all constants
  6847 are regarded as potentially overloaded, which improves robustness in exchange
  6848 for slight decrease in efficiency;
  6849 
  6850 * Provers/linorder: New generic prover for transitivity reasoning over
  6851 linear orders.  Note: this prover is not efficient!
  6852 
  6853 * Isar: preview of problems to finish 'show' now produce an error
  6854 rather than just a warning (in interactive mode);
  6855 
  6856 
  6857 *** HOL ***
  6858 
  6859 * arith(_tac)
  6860 
  6861  - Produces a counter example if it cannot prove a goal.
  6862    Note that the counter example may be spurious if the goal is not a formula
  6863    of quantifier-free linear arithmetic.
  6864    In ProofGeneral the counter example appears in the trace buffer.
  6865 
  6866  - Knows about div k and mod k where k is a numeral of type nat or int.
  6867 
  6868  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6869    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6870    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6871 
  6872 * simp's arithmetic capabilities have been enhanced a bit: it now
  6873 takes ~= in premises into account (by performing a case split);
  6874 
  6875 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6876 are distributed over a sum of terms;
  6877 
  6878 * New tactic "trans_tac" and method "trans" instantiate
  6879 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6880 "<=", "<" and "=").
  6881 
  6882 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6883 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6884 
  6885 * 'typedef' command has new option "open" to suppress the set
  6886 definition;
  6887 
  6888 * functions Min and Max on finite sets have been introduced (theory
  6889 Finite_Set);
  6890 
  6891 * attribute [symmetric] now works for relations as well; it turns
  6892 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6893 
  6894 * induct over a !!-quantified statement (say !!x1..xn):
  6895   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6896 
  6897 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6898 %x. None. Warning: empty_def now refers to the previously hidden definition
  6899 of the empty set.
  6900 
  6901 * Algebra: formalization of classical algebra.  Intended as base for
  6902 any algebraic development in Isabelle.  Currently covers group theory
  6903 (up to Sylow's theorem) and ring theory (Universal Property of
  6904 Univariate Polynomials).  Contributions welcome;
  6905 
  6906 * GroupTheory: deleted, since its material has been moved to Algebra;
  6907 
  6908 * Complex: new directory of the complex numbers with numeric constants,
  6909 nonstandard complex numbers, and some complex analysis, standard and
  6910 nonstandard (Jacques Fleuriot);
  6911 
  6912 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6913 
  6914 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6915 Fleuriot);
  6916 
  6917 * Real/HahnBanach: updated and adapted to locales;
  6918 
  6919 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6920 Gray and Kramer);
  6921 
  6922 * UNITY: added the Meier-Sanders theory of progress sets;
  6923 
  6924 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6925 as abstract algorithms, instantiated to the JVM;
  6926 
  6927 * Bali: Java source language formalization. Type system, operational
  6928 semantics, axiomatic semantics. Supported language features:
  6929 classes, interfaces, objects,virtual methods, static methods,
  6930 static/instance fields, arrays, access modifiers, definite
  6931 assignment, exceptions.
  6932 
  6933 
  6934 *** ZF ***
  6935 
  6936 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6937 universe, etc.);
  6938 
  6939 * Main ZF: virtually all theories converted to new-style format;
  6940 
  6941 
  6942 *** ML ***
  6943 
  6944 * Pure: Tactic.prove provides sane interface for internal proofs;
  6945 omits the infamous "standard" operation, so this is more appropriate
  6946 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6947 
  6948 * Pure: improved error reporting of simprocs;
  6949 
  6950 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6951 up simprocs;
  6952 
  6953 
  6954 *** Document preparation ***
  6955 
  6956 * uses \par instead of \\ for line breaks in theory text. This may
  6957 shift some page breaks in large documents. To get the old behaviour
  6958 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6959 
  6960 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6961 other packages
  6962 
  6963 * \<euro> now needs package babel/greek instead of marvosym (which
  6964 broke \Rightarrow)
  6965 
  6966 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6967 textcomp package)
  6968 
  6969 
  6970 
  6971 New in Isabelle2002 (March 2002)
  6972 --------------------------------
  6973 
  6974 *** Document preparation ***
  6975 
  6976 * greatly simplified document preparation setup, including more
  6977 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6978 instructive isatool mkdir; users should basically be able to get
  6979 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6980 users may run a separate document processing stage manually like this:
  6981 "isatool usedir -D output HOL Test && isatool document Test/output";
  6982 
  6983 * theory dependency graph may now be incorporated into documents;
  6984 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6985 with \includegraphics of LaTeX;
  6986 
  6987 * proper spacing of consecutive markup elements, especially text
  6988 blocks after section headings;
  6989 
  6990 * support bold style (for single symbols only), input syntax is like
  6991 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6992 
  6993 * \<bullet> is now output as bold \cdot by default, which looks much
  6994 better in printed text;
  6995 
  6996 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6997 note that these symbols are currently unavailable in Proof General /
  6998 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6999 
  7000 * isatool latex no longer depends on changed TEXINPUTS, instead
  7001 isatool document copies the Isabelle style files to the target
  7002 location;
  7003 
  7004 
  7005 *** Isar ***
  7006 
  7007 * Pure/Provers: improved proof by cases and induction;
  7008   - 'case' command admits impromptu naming of parameters (such as
  7009     "case (Suc n)");
  7010   - 'induct' method divinates rule instantiation from the inductive
  7011     claim; no longer requires excessive ?P bindings for proper
  7012     instantiation of cases;
  7013   - 'induct' method properly enumerates all possibilities of set/type
  7014     rules; as a consequence facts may be also passed through *type*
  7015     rules without further ado;
  7016   - 'induct' method now derives symbolic cases from the *rulified*
  7017     rule (before it used to rulify cases stemming from the internal
  7018     atomized version); this means that the context of a non-atomic
  7019     statement becomes is included in the hypothesis, avoiding the
  7020     slightly cumbersome show "PROP ?case" form;
  7021   - 'induct' may now use elim-style induction rules without chaining
  7022     facts, using ``missing'' premises from the goal state; this allows
  7023     rules stemming from inductive sets to be applied in unstructured
  7024     scripts, while still benefitting from proper handling of non-atomic
  7025     statements; NB: major inductive premises need to be put first, all
  7026     the rest of the goal is passed through the induction;
  7027   - 'induct' proper support for mutual induction involving non-atomic
  7028     rule statements (uses the new concept of simultaneous goals, see
  7029     below);
  7030   - append all possible rule selections, but only use the first
  7031     success (no backtracking);
  7032   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  7033   - undeclared rule case names default to numbers 1, 2, 3, ...;
  7034   - added 'print_induct_rules' (covered by help item in recent Proof
  7035     General versions);
  7036   - moved induct/cases attributes to Pure, methods to Provers;
  7037   - generic method setup instantiated for FOL and HOL;
  7038 
  7039 * Pure: support multiple simultaneous goal statements, for example
  7040 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  7041 meta-level mechanism, this acts as if several individual goals had
  7042 been stated separately; in particular common proof methods need to be
  7043 repeated in order to cover all claims; note that a single elimination
  7044 step is *not* sufficient to establish the two conjunctions, so this
  7045 fails:
  7046 
  7047   assume "A & B" then have A and B ..   (*".." fails*)
  7048 
  7049 better use "obtain" in situations as above; alternative refer to
  7050 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  7051 
  7052 * Pure: proper integration with ``locales''; unlike the original
  7053 version by Florian Kammller, Isar locales package high-level proof
  7054 contexts rather than raw logical ones (e.g. we admit to include
  7055 attributes everywhere); operations on locales include merge and
  7056 rename; support for implicit arguments (``structures''); simultaneous
  7057 type-inference over imports and text; see also HOL/ex/Locales.thy for
  7058 some examples;
  7059 
  7060 * Pure: the following commands have been ``localized'', supporting a
  7061 target locale specification "(in name)": 'lemma', 'theorem',
  7062 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  7063 stored both within the locale and at the theory level (exported and
  7064 qualified by the locale name);
  7065 
  7066 * Pure: theory goals may now be specified in ``long'' form, with
  7067 ad-hoc contexts consisting of arbitrary locale elements. for example
  7068 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  7069 definitions may be given, too); the result is a meta-level rule with
  7070 the context elements being discharged in the obvious way;
  7071 
  7072 * Pure: new proof command 'using' allows to augment currently used
  7073 facts after a goal statement ('using' is syntactically analogous to
  7074 'apply', but acts on the goal's facts only); this allows chained facts
  7075 to be separated into parts given before and after a claim, as in
  7076 ``from a and b have C using d and e <proof>'';
  7077 
  7078 * Pure: renamed "antecedent" case to "rule_context";
  7079 
  7080 * Pure: new 'judgment' command records explicit information about the
  7081 object-logic embedding (used by several tools internally); no longer
  7082 use hard-wired "Trueprop";
  7083 
  7084 * Pure: added 'corollary' command;
  7085 
  7086 * Pure: fixed 'token_translation' command;
  7087 
  7088 * Pure: removed obsolete 'exported' attribute;
  7089 
  7090 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  7091 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  7092 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  7093 
  7094 * Pure: method 'atomize' presents local goal premises as object-level
  7095 statements (atomic meta-level propositions); setup controlled via
  7096 rewrite rules declarations of 'atomize' attribute; example
  7097 application: 'induct' method with proper rule statements in improper
  7098 proof *scripts*;
  7099 
  7100 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  7101 now consider the syntactic context of assumptions, giving a better
  7102 chance to get type-inference of the arguments right (this is
  7103 especially important for locales);
  7104 
  7105 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  7106 mode;
  7107 
  7108 * Pure/obtain: the formal conclusion "thesis", being marked as
  7109 ``internal'', may no longer be reference directly in the text;
  7110 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  7111 situations;
  7112 
  7113 * Pure: generic 'sym' attribute which declares a rule both as pure
  7114 'elim?' and for the 'symmetric' operation;
  7115 
  7116 * Pure: marginal comments ``--'' may now occur just anywhere in the
  7117 text; the fixed correlation with particular command syntax has been
  7118 discontinued;
  7119 
  7120 * Pure: new method 'rules' is particularly well-suited for proof
  7121 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  7122 but often produces more compact proof terms with less detours;
  7123 
  7124 * Pure/Provers/classical: simplified integration with pure rule
  7125 attributes and methods; the classical "intro?/elim?/dest?"
  7126 declarations coincide with the pure ones; the "rule" method no longer
  7127 includes classically swapped intros; "intro" and "elim" methods no
  7128 longer pick rules from the context; also got rid of ML declarations
  7129 AddXIs/AddXEs/AddXDs; all of this has some potential for
  7130 INCOMPATIBILITY;
  7131 
  7132 * Provers/classical: attribute 'swapped' produces classical inversions
  7133 of introduction rules;
  7134 
  7135 * Provers/simplifier: 'simplified' attribute may refer to explicit
  7136 rules instead of full simplifier context; 'iff' attribute handles
  7137 conditional rules;
  7138 
  7139 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  7140 
  7141 * HOL: 'recdef' now fails on unfinished automated proofs, use
  7142 "(permissive)" option to recover old behavior;
  7143 
  7144 * HOL: 'inductive' no longer features separate (collective) attributes
  7145 for 'intros' (was found too confusing);
  7146 
  7147 * HOL: properly declared induction rules less_induct and
  7148 wf_induct_rule;
  7149 
  7150 
  7151 *** HOL ***
  7152 
  7153 * HOL: moved over to sane numeral syntax; the new policy is as
  7154 follows:
  7155 
  7156   - 0 and 1 are polymorphic constants, which are defined on any
  7157   numeric type (nat, int, real etc.);
  7158 
  7159   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  7160   binary representation internally;
  7161 
  7162   - type nat has special constructor Suc, and generally prefers Suc 0
  7163   over 1::nat and Suc (Suc 0) over 2::nat;
  7164 
  7165 This change may cause significant problems of INCOMPATIBILITY; here
  7166 are some hints on converting existing sources:
  7167 
  7168   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  7169   entities, so expressions involving "-" (unary or binary minus) need
  7170   to be spaced properly;
  7171 
  7172   - existing occurrences of "1" may need to be constraint "1::nat" or
  7173   even replaced by Suc 0; similar for old "2";
  7174 
  7175   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  7176 
  7177   - remove all special provisions on numerals in proofs;
  7178 
  7179 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  7180 representation (depends on bin_arith_simps in the default context);
  7181 
  7182 * HOL: symbolic syntax for x^2 (numeral 2);
  7183 
  7184 * HOL: the class of all HOL types is now called "type" rather than
  7185 "term"; INCOMPATIBILITY, need to adapt references to this type class
  7186 in axclass/classes, instance/arities, and (usually rare) occurrences
  7187 in typings (of consts etc.); internally the class is called
  7188 "HOL.type", ML programs should refer to HOLogic.typeS;
  7189 
  7190 * HOL/record package improvements:
  7191   - new derived operations "fields" to build a partial record section,
  7192     "extend" to promote a fixed record to a record scheme, and
  7193     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  7194     declared as simp by default;
  7195   - shared operations ("more", "fields", etc.) now need to be always
  7196     qualified) --- potential INCOMPATIBILITY;
  7197   - removed "make_scheme" operations (use "make" with "extend") --
  7198     INCOMPATIBILITY;
  7199   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  7200   - provides cases/induct rules for use with corresponding Isar
  7201     methods (for concrete records, record schemes, concrete more
  7202     parts, and schematic more parts -- in that order);
  7203   - internal definitions directly based on a light-weight abstract
  7204     theory of product types over typedef rather than datatype;
  7205 
  7206 * HOL: generic code generator for generating executable ML code from
  7207 specifications; specific support for HOL constructs such as inductive
  7208 datatypes and sets, as well as recursive functions; can be invoked
  7209 via 'generate_code' theory section;
  7210 
  7211 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  7212 
  7213 * HOL: consolidated and renamed several theories.  In particular:
  7214         Ord.thy has been absorbed into HOL.thy
  7215         String.thy has been absorbed into List.thy
  7216 
  7217 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  7218 (beware of argument permutation!);
  7219 
  7220 * HOL: linorder_less_split superseded by linorder_cases;
  7221 
  7222 * HOL/List: "nodups" renamed to "distinct";
  7223 
  7224 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  7225 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  7226   - Ex_def has changed, now need to use some_eq_ex
  7227 
  7228 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  7229 in this (rare) case use:
  7230 
  7231   delSWrapper "split_all_tac"
  7232   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  7233 
  7234 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  7235 MAY FAIL;
  7236 
  7237 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  7238 Isabelle's type classes, ^ on functions and relations has too general
  7239 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  7240 necessary to attach explicit type constraints;
  7241 
  7242 * HOL/Relation: the prefix name of the infix "O" has been changed from
  7243 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  7244 renamed accordingly (eg "compI" -> "rel_compI").
  7245 
  7246 * HOL: syntax translations now work properly with numerals and records
  7247 expressions;
  7248 
  7249 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  7250 of "lam" -- INCOMPATIBILITY;
  7251 
  7252 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  7253 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  7254 renamed "Product_Type.unit";
  7255 
  7256 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  7257 
  7258 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  7259 the "cases" method);
  7260 
  7261 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  7262 Florian Kammller);
  7263 
  7264 * HOL/IMP: updated and converted to new-style theory format; several
  7265 parts turned into readable document, with proper Isar proof texts and
  7266 some explanations (by Gerwin Klein);
  7267 
  7268 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  7269 
  7270 * HOL-Hyperreal is now a logic image;
  7271 
  7272 
  7273 *** HOLCF ***
  7274 
  7275 * Isar: consts/constdefs supports mixfix syntax for continuous
  7276 operations;
  7277 
  7278 * Isar: domain package adapted to new-style theory format, e.g. see
  7279 HOLCF/ex/Dnat.thy;
  7280 
  7281 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7282 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7283 lift.induct_tac, always use UU instead of Undef;
  7284 
  7285 * HOLCF/IMP: updated and converted to new-style theory;
  7286 
  7287 
  7288 *** ZF ***
  7289 
  7290 * Isar: proper integration of logic-specific tools and packages,
  7291 including theory commands '(co)inductive', '(co)datatype',
  7292 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7293 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7294 
  7295 * theory Main no longer includes AC; for the Axiom of Choice, base
  7296 your theory on Main_ZFC;
  7297 
  7298 * the integer library now covers quotients and remainders, with many
  7299 laws relating division to addition, multiplication, etc.;
  7300 
  7301 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7302 typeless version of the formalism;
  7303 
  7304 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7305 format;
  7306 
  7307 * ZF/Induct: new directory for examples of inductive definitions,
  7308 including theory Multiset for multiset orderings; converted to
  7309 new-style theory format;
  7310 
  7311 * ZF: many new theorems about lists, ordinals, etc.;
  7312 
  7313 
  7314 *** General ***
  7315 
  7316 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7317 variable proof controls level of detail: 0 = no proofs (only oracle
  7318 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7319 also ref manual for further ML interfaces;
  7320 
  7321 * Pure/axclass: removed obsolete ML interface
  7322 goal_subclass/goal_arity;
  7323 
  7324 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7325 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7326 separate tokens, so expressions involving minus need to be spaced
  7327 properly;
  7328 
  7329 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7330 rather than "infixl" or "infixr";
  7331 
  7332 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7333 sort constraint specifications in type inference; e.g. "x::_::foo"
  7334 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7335 type variable);
  7336 
  7337 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7338 control output of nested => (types); the default behavior is
  7339 "type_brackets";
  7340 
  7341 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7342 tokens into AST constants;
  7343 
  7344 * Pure/syntax: prefer later declarations of translations and print
  7345 translation functions; potential INCOMPATIBILITY: need to reverse
  7346 multiple declarations for same syntax element constant;
  7347 
  7348 * Pure/show_hyps reset by default (in accordance to existing Isar
  7349 practice);
  7350 
  7351 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7352 addSafter;
  7353 
  7354 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7355 as well;
  7356 
  7357 * system: tested support for MacOS X; should be able to get Isabelle +
  7358 Proof General to work in a plain Terminal after installing Poly/ML
  7359 (e.g. from the Isabelle distribution area) and GNU bash alone
  7360 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7361 support requires further installations, e.g. from
  7362 http://fink.sourceforge.net/);
  7363 
  7364 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7365 
  7366 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7367 of 40 MB), cf. ML_OPTIONS;
  7368 
  7369 * system: Proof General keywords specification is now part of the
  7370 Isabelle distribution (see etc/isar-keywords.el);
  7371 
  7372 * system: support for persistent Proof General sessions (refrain from
  7373 outdating all loaded theories on startup); user may create writable
  7374 logic images like this: ``isabelle -q HOL Test'';
  7375 
  7376 * system: smart selection of Isabelle process versus Isabelle
  7377 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7378 run both "isabelle" and "Isabelle" even if file names are badly
  7379 damaged (executable inspects the case of the first letter of its own
  7380 name); added separate "isabelle-process" and "isabelle-interface";
  7381 
  7382 * system: refrain from any attempt at filtering input streams; no
  7383 longer support ``8bit'' encoding of old isabelle font, instead proper
  7384 iso-latin characters may now be used; the related isatools
  7385 "symbolinput" and "nonascii" have disappeared as well;
  7386 
  7387 * system: removed old "xterm" interface (the print modes "xterm" and
  7388 "xterm_color" are still available for direct use in a suitable
  7389 terminal);
  7390 
  7391 
  7392 
  7393 New in Isabelle99-2 (February 2001)
  7394 -----------------------------------
  7395 
  7396 *** Overview of INCOMPATIBILITIES ***
  7397 
  7398 * HOL: please note that theories in the Library and elsewhere often use the
  7399 new-style (Isar) format; to refer to their theorems in an ML script you must
  7400 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  7401 
  7402 * HOL: inductive package no longer splits induction rule aggressively,
  7403 but only as far as specified by the introductions given; the old
  7404 format may be recovered via ML function complete_split_rule or attribute
  7405 'split_rule (complete)';
  7406 
  7407 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  7408 gfp_Tarski to gfp_unfold;
  7409 
  7410 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  7411 
  7412 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  7413 relation); infix "^^" has been renamed "``"; infix "``" has been
  7414 renamed "`"; "univalent" has been renamed "single_valued";
  7415 
  7416 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  7417 operation;
  7418 
  7419 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  7420 
  7421 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  7422 
  7423 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  7424 consequence, it is no longer monotonic wrt. the local goal context
  7425 (which is now passed through the inductive cases);
  7426 
  7427 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  7428 \<gg> to \<ggreater>;
  7429 
  7430 
  7431 *** Document preparation ***
  7432 
  7433 * \isabellestyle{NAME} selects version of Isabelle output (currently
  7434 available: are "it" for near math-mode best-style output, "sl" for
  7435 slanted text style, and "tt" for plain type-writer; if no
  7436 \isabellestyle command is given, output is according to slanted
  7437 type-writer);
  7438 
  7439 * support sub/super scripts (for single symbols only), input syntax is
  7440 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  7441 
  7442 * some more standard symbols; see Appendix A of the system manual for
  7443 the complete list of symbols defined in isabellesym.sty;
  7444 
  7445 * improved isabelle style files; more abstract symbol implementation
  7446 (should now use \isamath{...} and \isatext{...} in custom symbol
  7447 definitions);
  7448 
  7449 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  7450 state; Note that presentation of goal states does not conform to
  7451 actual human-readable proof documents.  Please do not include goal
  7452 states into document output unless you really know what you are doing!
  7453 
  7454 * proper indentation of antiquoted output with proportional LaTeX
  7455 fonts;
  7456 
  7457 * no_document ML operator temporarily disables LaTeX document
  7458 generation;
  7459 
  7460 * isatool unsymbolize tunes sources for plain ASCII communication;
  7461 
  7462 
  7463 *** Isar ***
  7464 
  7465 * Pure: Isar now suffers initial goal statements to contain unbound
  7466 schematic variables (this does not conform to actual readable proof
  7467 documents, due to unpredictable outcome and non-compositional proof
  7468 checking); users who know what they are doing may use schematic goals
  7469 for Prolog-style synthesis of proven results;
  7470 
  7471 * Pure: assumption method (an implicit finishing) now handles actual
  7472 rules as well;
  7473 
  7474 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  7475 initial goal, declare "that" only as Pure intro (only for single
  7476 steps); the "that" rule assumption may now be involved in implicit
  7477 finishing, thus ".." becomes a feasible for trivial obtains;
  7478 
  7479 * Pure: default proof step now includes 'intro_classes'; thus trivial
  7480 instance proofs may be performed by "..";
  7481 
  7482 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  7483 statements as well;
  7484 
  7485 * Pure: more robust selection of calculational rules;
  7486 
  7487 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  7488 rule (as well as the assumption rule);
  7489 
  7490 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  7491 lemmas, using the graph browser tool;
  7492 
  7493 * Pure: predict failure of "show" in interactive mode;
  7494 
  7495 * Pure: 'thms_containing' now takes actual terms as arguments;
  7496 
  7497 * HOL: improved method 'induct' --- now handles non-atomic goals
  7498 (potential INCOMPATIBILITY); tuned error handling;
  7499 
  7500 * HOL: cases and induct rules now provide explicit hints about the
  7501 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  7502 any remaining facts are inserted into the goal verbatim;
  7503 
  7504 * HOL: local contexts (aka cases) may now contain term bindings as
  7505 well; the 'cases' and 'induct' methods new provide a ?case binding for
  7506 the result to be shown in each case;
  7507 
  7508 * HOL: added 'recdef_tc' command;
  7509 
  7510 * isatool convert assists in eliminating legacy ML scripts;
  7511 
  7512 
  7513 *** HOL ***
  7514 
  7515 * HOL/Library: a collection of generic theories to be used together
  7516 with main HOL; the theory loader path already includes this directory
  7517 by default; the following existing theories have been moved here:
  7518 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  7519 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  7520 
  7521 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  7522 modelling and verification task performed in Isabelle/HOL +
  7523 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  7524 
  7525 * HOL/Algebra: special summation operator SUM no longer exists, it has
  7526 been replaced by setsum; infix 'assoc' now has priority 50 (like
  7527 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  7528 'domain', this makes the theory consistent with mathematical
  7529 literature;
  7530 
  7531 * HOL basics: added overloaded operations "inverse" and "divide"
  7532 (infix "/"), syntax for generic "abs" operation, generic summation
  7533 operator \<Sum>;
  7534 
  7535 * HOL/typedef: simplified package, provide more useful rules (see also
  7536 HOL/subset.thy);
  7537 
  7538 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  7539 now expressed as a proper nested rule (old-style tactic scripts may
  7540 require atomize_strip_tac to cope with non-atomic premises);
  7541 
  7542 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  7543 to "split_conv" (old name still available for compatibility);
  7544 
  7545 * HOL: improved concrete syntax for strings (e.g. allows translation
  7546 rules with string literals);
  7547 
  7548 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  7549  and Fleuriot's mechanization of analysis, including the transcendental
  7550  functions for the reals;
  7551 
  7552 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  7553 
  7554 
  7555 *** CTT ***
  7556 
  7557 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  7558 "lam" is displayed as TWO lambda-symbols
  7559 
  7560 * CTT: theory Main now available, containing everything (that is, Bool
  7561 and Arith);
  7562 
  7563 
  7564 *** General ***
  7565 
  7566 * Pure: the Simplifier has been implemented properly as a derived rule
  7567 outside of the actual kernel (at last!); the overall performance
  7568 penalty in practical applications is about 50%, while reliability of
  7569 the Isabelle inference kernel has been greatly improved;
  7570 
  7571 * print modes "brackets" and "no_brackets" control output of nested =>
  7572 (types) and ==> (props); the default behaviour is "brackets";
  7573 
  7574 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7575 as assumptions as well;
  7576 
  7577 * system: support Poly/ML 4.0;
  7578 
  7579 * system: isatool install handles KDE version 1 or 2;
  7580 
  7581 
  7582 
  7583 New in Isabelle99-1 (October 2000)
  7584 ----------------------------------
  7585 
  7586 *** Overview of INCOMPATIBILITIES ***
  7587 
  7588 * HOL: simplification of natural numbers is much changed; to partly
  7589 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7590 issue the following ML commands:
  7591 
  7592   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7593   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7594 
  7595 * HOL: simplification no longer dives into case-expressions; this is
  7596 controlled by "t.weak_case_cong" for each datatype t;
  7597 
  7598 * HOL: nat_less_induct renamed to less_induct;
  7599 
  7600 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7601 fixsome to patch .thy and .ML sources automatically;
  7602 
  7603   select_equality  -> some_equality
  7604   select_eq_Ex     -> some_eq_ex
  7605   selectI2EX       -> someI2_ex
  7606   selectI2         -> someI2
  7607   selectI          -> someI
  7608   select1_equality -> some1_equality
  7609   Eps_sym_eq       -> some_sym_eq_trivial
  7610   Eps_eq           -> some_eq_trivial
  7611 
  7612 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7613 
  7614 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7615 instead);
  7616 
  7617 * HOL: the recursion equations generated by 'recdef' are now called
  7618 f.simps instead of f.rules;
  7619 
  7620 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7621 
  7622 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7623 sometimes be needed;
  7624 
  7625 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7626 
  7627 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7628 
  7629 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7630 product is now "<*>" instead of "Times"; the lexicographic product is
  7631 now "<*lex*>" instead of "**";
  7632 
  7633 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7634 of main HOL, but was unused); better use HOL's datatype package;
  7635 
  7636 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7637 the old syntax may be recovered as follows:
  7638 
  7639   syntax (symbols)
  7640     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7641       (infixl "\\<oplus>" 100)
  7642 
  7643 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7644 
  7645 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7646 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7647 internally;
  7648 
  7649 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7650 changed from A/r to A//r;
  7651 
  7652 * ZF: new treatment of arithmetic (nat & int) may break some old
  7653 proofs;
  7654 
  7655 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7656 rulify -> rule_format, elimify -> elim_format, ...);
  7657 
  7658 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7659 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7660 should have to change intro!! to intro? only); replaced "delrule" by
  7661 "rule del";
  7662 
  7663 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7664 
  7665 * Provers: strengthened force_tac by using new first_best_tac;
  7666 
  7667 * LaTeX document preparation: several changes of isabelle.sty (see
  7668 lib/texinputs);
  7669 
  7670 
  7671 *** Document preparation ***
  7672 
  7673 * formal comments (text blocks etc.) in new-style theories may now
  7674 contain antiquotations of thm/prop/term/typ/text to be presented
  7675 according to latex print mode; concrete syntax is like this:
  7676 @{term[show_types] "f(x) = a + x"};
  7677 
  7678 * isatool mkdir provides easy setup of Isabelle session directories,
  7679 including proper document sources;
  7680 
  7681 * generated LaTeX sources are now deleted after successful run
  7682 (isatool document -c); may retain a copy somewhere else via -D option
  7683 of isatool usedir;
  7684 
  7685 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7686 style files, achieving self-contained LaTeX sources and simplifying
  7687 LaTeX debugging;
  7688 
  7689 * old-style theories now produce (crude) LaTeX output as well;
  7690 
  7691 * browser info session directories are now self-contained (may be put
  7692 on WWW server seperately); improved graphs of nested sessions; removed
  7693 graph for 'all sessions';
  7694 
  7695 * several improvements in isabelle style files; \isabellestyle{it}
  7696 produces fake math mode output; \isamarkupheader is now \section by
  7697 default; see lib/texinputs/isabelle.sty etc.;
  7698 
  7699 
  7700 *** Isar ***
  7701 
  7702 * Isar/Pure: local results and corresponding term bindings are now
  7703 subject to Hindley-Milner polymorphism (similar to ML); this
  7704 accommodates incremental type-inference very nicely;
  7705 
  7706 * Isar/Pure: new derived language element 'obtain' supports
  7707 generalized existence reasoning;
  7708 
  7709 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7710 support accumulation of results, without applying any rules yet;
  7711 useful to collect intermediate results without explicit name
  7712 references, and for use with transitivity rules with more than 2
  7713 premises;
  7714 
  7715 * Isar/Pure: scalable support for case-analysis type proofs: new
  7716 'case' language element refers to local contexts symbolically, as
  7717 produced by certain proof methods; internally, case names are attached
  7718 to theorems as "tags";
  7719 
  7720 * Isar/Pure: theory command 'hide' removes declarations from
  7721 class/type/const name spaces;
  7722 
  7723 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7724 indicate potential overloading;
  7725 
  7726 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7727 
  7728 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7729 "{a,b,c}" instead of {a,b,c};
  7730 
  7731 * Isar/Pure now provides its own version of intro/elim/dest
  7732 attributes; useful for building new logics, but beware of confusion
  7733 with the version in Provers/classical;
  7734 
  7735 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7736 case name 'antecedent';
  7737 
  7738 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7739 to the current context is now done automatically);
  7740 
  7741 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7742 for definining proof methods in ML;
  7743 
  7744 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7745 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7746 most cases, one should have to change intro!! to intro? only);
  7747 replaced "delrule" by "rule del";
  7748 
  7749 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7750 'symmetric' attribute (the latter supercedes [RS sym]);
  7751 
  7752 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7753 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7754 well (including splits);
  7755 
  7756 * Isar/Provers: Simplifier and Classical methods now support all kind
  7757 of modifiers used in the past, including 'cong', 'iff', etc.
  7758 
  7759 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7760 of Simplifier and Classical reasoner);
  7761 
  7762 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7763 now support named cases; major packages (inductive, datatype, primrec,
  7764 recdef) support case names and properly name parameters;
  7765 
  7766 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7767 monotonicity conditions are extracted to be proven at end of
  7768 calculations;
  7769 
  7770 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7771 method anyway;
  7772 
  7773 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7774 split_if split_if_asm; datatype package provides theorems foo.splits =
  7775 foo.split foo.split_asm for each datatype;
  7776 
  7777 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7778 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7779 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  7780 use "(cases (simplified))" method in proper proof texts);
  7781 
  7782 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  7783 
  7784 * Isar: names of theorems etc. may be natural numbers as well;
  7785 
  7786 * Isar: 'pr' command: optional arguments for goals_limit and
  7787 ProofContext.prems_limit; no longer prints theory contexts, but only
  7788 proof states;
  7789 
  7790 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  7791 additional print modes to be specified; e.g. "pr(latex)" will print
  7792 proof state according to the Isabelle LaTeX style;
  7793 
  7794 * Isar: improved support for emulating tactic scripts, including proof
  7795 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  7796 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  7797 (for HOL datatypes);
  7798 
  7799 * Isar: simplified (more robust) goal selection of proof methods: 1st
  7800 goal, all goals, or explicit goal specifier (tactic emulation); thus
  7801 'proof method scripts' have to be in depth-first order;
  7802 
  7803 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  7804 
  7805 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  7806 should instead use individual commands for printing items
  7807 (print_commands, print_methods etc.);
  7808 
  7809 * Isar: added 'nothing' --- the empty list of theorems;
  7810 
  7811 
  7812 *** HOL ***
  7813 
  7814 * HOL/MicroJava: formalization of a fragment of Java, together with a
  7815 corresponding virtual machine and a specification of its bytecode
  7816 verifier and a lightweight bytecode verifier, including proofs of
  7817 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  7818 Cornelia Pusch (see also the homepage of project Bali at
  7819 http://isabelle.in.tum.de/Bali/);
  7820 
  7821 * HOL/Algebra: new theory of rings and univariate polynomials, by
  7822 Clemens Ballarin;
  7823 
  7824 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  7825 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  7826 Rasmussen;
  7827 
  7828 * HOL/Lattice: fundamental concepts of lattice theory and order
  7829 structures, including duals, properties of bounds versus algebraic
  7830 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  7831 Theorem for complete lattices etc.; may also serve as a demonstration
  7832 for abstract algebraic reasoning using axiomatic type classes, and
  7833 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  7834 
  7835 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  7836 von Oheimb;
  7837 
  7838 * HOL/IMPP: extension of IMP with local variables and mutually
  7839 recursive procedures, by David von Oheimb;
  7840 
  7841 * HOL/Lambda: converted into new-style theory and document;
  7842 
  7843 * HOL/ex/Multiquote: example of multiple nested quotations and
  7844 anti-quotations -- basically a generalized version of de-Bruijn
  7845 representation; very useful in avoiding lifting of operations;
  7846 
  7847 * HOL/record: added general record equality rule to simpset; fixed
  7848 select-update simplification procedure to handle extended records as
  7849 well; admit "r" as field name;
  7850 
  7851 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  7852 other numeric types and also as the identity of groups, rings, etc.;
  7853 
  7854 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  7855 Types nat and int belong to this axclass;
  7856 
  7857 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  7858    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  7859    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  7860   two terms #m*u and #n*u are replaced by #(m+n)*u
  7861     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  7862   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  7863     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  7864 
  7865 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  7866 powerful prover for predicate logic but knows nothing of clasets; see
  7867 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  7868 
  7869 * HOL: new version of "case_tac" subsumes both boolean case split and
  7870 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  7871 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  7872 
  7873 * HOL: simplification no longer dives into case-expressions: only the
  7874 selector expression is simplified, but not the remaining arms; to
  7875 enable full simplification of case-expressions for datatype t, you may
  7876 remove t.weak_case_cong from the simpset, either globally (Delcongs
  7877 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  7878 
  7879 * HOL/recdef: the recursion equations generated by 'recdef' for
  7880 function 'f' are now called f.simps instead of f.rules; if all
  7881 termination conditions are proved automatically, these simplification
  7882 rules are added to the simpset, as in primrec; rules may be named
  7883 individually as well, resulting in a separate list of theorems for
  7884 each equation;
  7885 
  7886 * HOL/While is a new theory that provides a while-combinator. It
  7887 permits the definition of tail-recursive functions without the
  7888 provision of a termination measure. The latter is necessary once the
  7889 invariant proof rule for while is applied.
  7890 
  7891 * HOL: new (overloaded) notation for the set of elements below/above
  7892 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  7893 
  7894 * HOL: theorems impI, allI, ballI bound as "strip";
  7895 
  7896 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  7897 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  7898 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  7899 
  7900 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7901 
  7902 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  7903 main HOL, but was unused);
  7904 
  7905 * HOL: fewer consts declared as global (e.g. have to refer to
  7906 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  7907 
  7908 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  7909 in case of overlap with user translations (e.g. judgements over
  7910 tuples); (note that the underlying logical represenation is still
  7911 bogus);
  7912 
  7913 
  7914 *** ZF ***
  7915 
  7916 * ZF: simplification automatically cancels common terms in arithmetic
  7917 expressions over nat and int;
  7918 
  7919 * ZF: new treatment of nat to minimize type-checking: all operators
  7920 coerce their operands to a natural number using the function natify,
  7921 making the algebraic laws unconditional;
  7922 
  7923 * ZF: as above, for int: operators coerce their operands to an integer
  7924 using the function intify;
  7925 
  7926 * ZF: the integer library now contains many of the usual laws for the
  7927 orderings, including $<=, and monotonicity laws for $+ and $*;
  7928 
  7929 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  7930 simplification;
  7931 
  7932 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  7933 to the simplifier and classical reasoner simultaneously;
  7934 
  7935 
  7936 *** General ***
  7937 
  7938 * Provers: blast_tac now handles actual object-logic rules as
  7939 assumptions; note that auto_tac uses blast_tac internally as well;
  7940 
  7941 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  7942 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  7943 
  7944 * Provers: delrules now handles destruct rules as well (no longer need
  7945 explicit make_elim);
  7946 
  7947 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  7948   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7949 use instead the strong form,
  7950   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7951 in HOL, FOL and ZF the function cla_make_elim will create such rules
  7952 from destruct-rules;
  7953 
  7954 * Provers: Simplifier.easy_setup provides a fast path to basic
  7955 Simplifier setup for new object-logics;
  7956 
  7957 * Pure: AST translation rules no longer require constant head on LHS;
  7958 
  7959 * Pure: improved name spaces: ambiguous output is qualified; support
  7960 for hiding of names;
  7961 
  7962 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  7963 XSYMBOL_HOME; no longer need to do manual configuration in most
  7964 situations;
  7965 
  7966 * system: compression of ML heaps images may now be controlled via -c
  7967 option of isabelle and isatool usedir (currently only observed by
  7968 Poly/ML);
  7969 
  7970 * system: isatool installfonts may handle X-Symbol fonts as well (very
  7971 useful for remote X11);
  7972 
  7973 * system: provide TAGS file for Isabelle sources;
  7974 
  7975 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  7976 order;
  7977 
  7978 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  7979 timing flag supersedes proof_timing and Toplevel.trace;
  7980 
  7981 * ML: new combinators |>> and |>>> for incremental transformations
  7982 with secondary results (e.g. certain theory extensions):
  7983 
  7984 * ML: PureThy.add_defs gets additional argument to indicate potential
  7985 overloading (usually false);
  7986 
  7987 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  7988 results;
  7989 
  7990 
  7991 
  7992 New in Isabelle99 (October 1999)
  7993 --------------------------------
  7994 
  7995 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7996 
  7997 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  7998 are no longer simplified.  (This allows the simplifier to unfold recursive
  7999 functional programs.)  To restore the old behaviour, declare
  8000 
  8001     Delcongs [if_weak_cong];
  8002 
  8003 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  8004 complement;
  8005 
  8006 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  8007 
  8008 * HOL/datatype: mutual_induct_tac no longer exists --
  8009   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  8010 
  8011 * HOL/typedef: fixed type inference for representing set; type
  8012 arguments now have to occur explicitly on the rhs as type constraints;
  8013 
  8014 * ZF: The con_defs part of an inductive definition may no longer refer
  8015 to constants declared in the same theory;
  8016 
  8017 * HOL, ZF: the function mk_cases, generated by the inductive
  8018 definition package, has lost an argument.  To simplify its result, it
  8019 uses the default simpset instead of a supplied list of theorems.
  8020 
  8021 * HOL/List: the constructors of type list are now Nil and Cons;
  8022 
  8023 * Simplifier: the type of the infix ML functions
  8024         setSSolver addSSolver setSolver addSolver
  8025 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  8026 for packaging solvers. A solver is created via
  8027         mk_solver: string -> (thm list -> int -> tactic) -> solver
  8028 where the string argument is only a comment.
  8029 
  8030 
  8031 *** Proof tools ***
  8032 
  8033 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  8034 decision procedure for linear arithmetic. Currently it is used for
  8035 types `nat', `int', and `real' in HOL (see below); it can, should and
  8036 will be instantiated for other types and logics as well.
  8037 
  8038 * The simplifier now accepts rewrite rules with flexible heads, eg
  8039      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  8040   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  8041   matching.
  8042 
  8043 
  8044 *** General ***
  8045 
  8046 * New Isabelle/Isar subsystem provides an alternative to traditional
  8047 tactical theorem proving; together with the ProofGeneral/isar user
  8048 interface it offers an interactive environment for developing human
  8049 readable proof documents (Isar == Intelligible semi-automated
  8050 reasoning); for further information see isatool doc isar-ref,
  8051 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  8052 
  8053 * improved and simplified presentation of theories: better HTML markup
  8054 (including colors), graph views in several sizes; isatool usedir now
  8055 provides a proper interface for user theories (via -P option); actual
  8056 document preparation based on (PDF)LaTeX is available as well (for
  8057 new-style theories only); see isatool doc system for more information;
  8058 
  8059 * native support for Proof General, both for classic Isabelle and
  8060 Isabelle/Isar;
  8061 
  8062 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  8063 using the graph browser tool;
  8064 
  8065 * Isabelle manuals now also available as PDF;
  8066 
  8067 * theory loader rewritten from scratch (may not be fully
  8068 bug-compatible); old loadpath variable has been replaced by show_path,
  8069 add_path, del_path, reset_path functions; new operations such as
  8070 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  8071 isatool doc ref);
  8072 
  8073 * improved isatool install: option -k creates KDE application icon,
  8074 option -p DIR installs standalone binaries;
  8075 
  8076 * added ML_PLATFORM setting (useful for cross-platform installations);
  8077 more robust handling of platform specific ML images for SML/NJ;
  8078 
  8079 * the settings environment is now statically scoped, i.e. it is never
  8080 created again in sub-processes invoked from isabelle, isatool, or
  8081 Isabelle;
  8082 
  8083 * path element specification '~~' refers to '$ISABELLE_HOME';
  8084 
  8085 * in locales, the "assumes" and "defines" parts may be omitted if
  8086 empty;
  8087 
  8088 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  8089 long arrows);
  8090 
  8091 * new print_mode "HTML";
  8092 
  8093 * new flag show_tags controls display of tags of theorems (which are
  8094 basically just comments that may be attached by some tools);
  8095 
  8096 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  8097 mode and goal output format:
  8098 
  8099 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  8100 244c244
  8101 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  8102 ---
  8103 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  8104 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  8105 181c181
  8106 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  8107 ---
  8108 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  8109 
  8110 * function bind_thms stores lists of theorems (cf. bind_thm);
  8111 
  8112 * new shorthand tactics ftac, eatac, datac, fatac;
  8113 
  8114 * qed (and friends) now accept "" as result name; in that case the
  8115 theorem is not stored, but proper checks and presentation of the
  8116 result still apply;
  8117 
  8118 * theorem database now also indexes constants "Trueprop", "all",
  8119 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  8120 
  8121 
  8122 *** HOL ***
  8123 
  8124 ** HOL arithmetic **
  8125 
  8126 * There are now decision procedures for linear arithmetic over nat and
  8127 int:
  8128 
  8129 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  8130 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  8131 are treated as atomic; subformulae not involving type `nat' or `int'
  8132 are ignored; quantified subformulae are ignored unless they are
  8133 positive universal or negative existential. The tactic has to be
  8134 invoked by hand and can be a little bit slow. In particular, the
  8135 running time is exponential in the number of occurrences of `min' and
  8136 `max', and `-' on `nat'.
  8137 
  8138 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  8139 (negated) (in)equalities among the premises and the conclusion into
  8140 account (i.e. no compound formulae) and does not know about `min' and
  8141 `max', and `-' on `nat'. It is fast and is used automatically by the
  8142 simplifier.
  8143 
  8144 NB: At the moment, these decision procedures do not cope with mixed
  8145 nat/int formulae where the two parts interact, such as `m < n ==>
  8146 int(m) < int(n)'.
  8147 
  8148 * HOL/Numeral provides a generic theory of numerals (encoded
  8149 efficiently as bit strings); setup for types nat/int/real is in place;
  8150 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  8151 int, existing theories and proof scripts may require a few additional
  8152 type constraints;
  8153 
  8154 * integer division and remainder can now be performed on constant
  8155 arguments;
  8156 
  8157 * many properties of integer multiplication, division and remainder
  8158 are now available;
  8159 
  8160 * An interface to the Stanford Validity Checker (SVC) is available through the
  8161 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  8162 are proved automatically.  SVC must be installed separately, and its results
  8163 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  8164 invocation of the underlying oracle).  For SVC see
  8165   http://verify.stanford.edu/SVC
  8166 
  8167 * IsaMakefile: the HOL-Real target now builds an actual image;
  8168 
  8169 
  8170 ** HOL misc **
  8171 
  8172 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  8173 (in Isabelle/Isar) -- by Gertrud Bauer;
  8174 
  8175 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  8176 analysis for assembly languages with subtypes;
  8177 
  8178 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  8179 -- avoids syntactic ambiguities and treats state, transition, and
  8180 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  8181 changed syntax and (many) tactics;
  8182 
  8183 * HOL/inductive: Now also handles more general introduction rules such
  8184   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  8185   theorems are now maintained within the theory (maintained via the
  8186   "mono" attribute);
  8187 
  8188 * HOL/datatype: Now also handles arbitrarily branching datatypes
  8189   (using function types) such as
  8190 
  8191   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  8192 
  8193 * HOL/record: record_simproc (part of the default simpset) takes care
  8194 of selectors applied to updated records; record_split_tac is no longer
  8195 part of the default claset; update_defs may now be removed from the
  8196 simpset in many cases; COMPATIBILITY: old behavior achieved by
  8197 
  8198   claset_ref () := claset() addSWrapper record_split_wrapper;
  8199   Delsimprocs [record_simproc]
  8200 
  8201 * HOL/typedef: fixed type inference for representing set; type
  8202 arguments now have to occur explicitly on the rhs as type constraints;
  8203 
  8204 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  8205 names rather than an ML expression;
  8206 
  8207 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  8208 supplied later.  Program schemes can be defined, such as
  8209     "While B C s = (if B s then While B C (C s) else s)"
  8210 where the well-founded relation can be chosen after B and C have been given.
  8211 
  8212 * HOL/List: the constructors of type list are now Nil and Cons;
  8213 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  8214 course, ML tools referring to List.list.op # etc. have to be adapted;
  8215 
  8216 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  8217 disabled by default; run isabelle with option -m HOL to get back to
  8218 the original Gordon/HOL-style output;
  8219 
  8220 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  8221 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  8222 
  8223 * HOL basic syntax simplified (more orthogonal): all variants of
  8224 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  8225 Eps operator is provided as well: "SOME x. P[x]";
  8226 
  8227 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  8228 
  8229 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  8230 thus available for user theories;
  8231 
  8232 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  8233 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  8234 time;
  8235 
  8236 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  8237 several times and then mp;
  8238 
  8239 
  8240 *** LK ***
  8241 
  8242 * the notation <<...>> is now available as a notation for sequences of
  8243 formulas;
  8244 
  8245 * the simplifier is now installed
  8246 
  8247 * the axiom system has been generalized (thanks to Soren Heilmann)
  8248 
  8249 * the classical reasoner now has a default rule database
  8250 
  8251 
  8252 *** ZF ***
  8253 
  8254 * new primrec section allows primitive recursive functions to be given
  8255 directly (as in HOL) over datatypes and the natural numbers;
  8256 
  8257 * new tactics induct_tac and exhaust_tac for induction (or case
  8258 analysis) over datatypes and the natural numbers;
  8259 
  8260 * the datatype declaration of type T now defines the recursor T_rec;
  8261 
  8262 * simplification automatically does freeness reasoning for datatype
  8263 constructors;
  8264 
  8265 * automatic type-inference, with AddTCs command to insert new
  8266 type-checking rules;
  8267 
  8268 * datatype introduction rules are now added as Safe Introduction rules
  8269 to the claset;
  8270 
  8271 * the syntax "if P then x else y" is now available in addition to
  8272 if(P,x,y);
  8273 
  8274 
  8275 *** Internal programming interfaces ***
  8276 
  8277 * tuned simplifier trace output; new flag debug_simp;
  8278 
  8279 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8280 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8281 
  8282 * AxClass.axclass_tac lost the theory argument;
  8283 
  8284 * tuned current_goals_markers semantics: begin / end goal avoids
  8285 printing empty lines;
  8286 
  8287 * removed prs and prs_fn hook, which was broken because it did not
  8288 include \n in its semantics, forcing writeln to add one
  8289 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8290 string -> unit if you really want to output text without newline;
  8291 
  8292 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8293 plain output, interface builders may have to enable 'isabelle_font'
  8294 mode to get Isabelle font glyphs as before;
  8295 
  8296 * refined token_translation interface; INCOMPATIBILITY: output length
  8297 now of type real instead of int;
  8298 
  8299 * theory loader actions may be traced via new ThyInfo.add_hook
  8300 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8301 your own database of information attached to *whole* theories -- as
  8302 opposed to intra-theory data slots offered via TheoryDataFun;
  8303 
  8304 * proper handling of dangling sort hypotheses (at last!);
  8305 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8306 extra sort hypotheses that can be witnessed from the type signature;
  8307 the force_strip_shyps flag is gone, any remaining shyps are simply
  8308 left in the theorem (with a warning issued by strip_shyps_warning);
  8309 
  8310 
  8311 
  8312 New in Isabelle98-1 (October 1998)
  8313 ----------------------------------
  8314 
  8315 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8316 
  8317 * several changes of automated proof tools;
  8318 
  8319 * HOL: major changes to the inductive and datatype packages, including
  8320 some minor incompatibilities of theory syntax;
  8321 
  8322 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8323 called `inj_on';
  8324 
  8325 * HOL: removed duplicate thms in Arith:
  8326   less_imp_add_less  should be replaced by  trans_less_add1
  8327   le_imp_add_le      should be replaced by  trans_le_add1
  8328 
  8329 * HOL: unary minus is now overloaded (new type constraints may be
  8330 required);
  8331 
  8332 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8333 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8334 now taken as an integer constant.
  8335 
  8336 * Pure: ML function 'theory_of' renamed to 'theory';
  8337 
  8338 
  8339 *** Proof tools ***
  8340 
  8341 * Simplifier:
  8342   1. Asm_full_simp_tac is now more aggressive.
  8343      1. It will sometimes reorient premises if that increases their power to
  8344         simplify.
  8345      2. It does no longer proceed strictly from left to right but may also
  8346         rotate premises to achieve further simplification.
  8347      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8348      old Asm_full_simp_tac in that it does not rotate premises.
  8349   2. The simplifier now knows a little bit about nat-arithmetic.
  8350 
  8351 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8352 allows for selected deletion of wrappers, by introduction of names for
  8353 wrapper functionals.  This implies that addbefore, addSbefore,
  8354 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8355 and that adding two tactics with the same name overwrites the first
  8356 one (emitting a warning).
  8357   type wrapper = (int -> tactic) -> (int -> tactic)
  8358   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8359   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8360   delWrapper, delSWrapper: claset *  string            -> claset
  8361   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8362 
  8363 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8364 semantics; addbefore now affects only the unsafe part of step_tac
  8365 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8366 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8367 by Force_tac;
  8368 
  8369 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8370 compWrapper; added safe wrapper (and access functions for it);
  8371 
  8372 * HOL/split_all_tac is now much faster and fails if there is nothing
  8373 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8374 and the names of the automatically generated variables have changed.
  8375 split_all_tac has moved within claset() from unsafe wrappers to safe
  8376 wrappers, which means that !!-bound variables are split much more
  8377 aggressively, and safe_tac and clarify_tac now split such variables.
  8378 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8379 Note: the same holds for record_split_tac, which does the job of
  8380 split_all_tac for record fields.
  8381 
  8382 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8383 permanently to the default simpset using Addsplits just like
  8384 Addsimps. They can be removed via Delsplits just like
  8385 Delsimps. Lower-case versions are also available.
  8386 
  8387 * HOL/Simplifier: The rule split_if is now part of the default
  8388 simpset. This means that the simplifier will eliminate all occurrences
  8389 of if-then-else in the conclusion of a goal. To prevent this, you can
  8390 either remove split_if completely from the default simpset by
  8391 `Delsplits [split_if]' or remove it in a specific call of the
  8392 simplifier using `... delsplits [split_if]'.  You can also add/delete
  8393 other case splitting rules to/from the default simpset: every datatype
  8394 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  8395 t is the name of the datatype).
  8396 
  8397 * Classical reasoner / Simplifier combination: new force_tac (and
  8398 derivatives Force_tac, force) combines rewriting and classical
  8399 reasoning (and whatever other tools) similarly to auto_tac, but is
  8400 aimed to solve the given subgoal completely.
  8401 
  8402 
  8403 *** General ***
  8404 
  8405 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  8406 and `goalw': the theory is no longer needed as an explicit argument -
  8407 the current theory context is used; assumptions are no longer returned
  8408 at the ML-level unless one of them starts with ==> or !!; it is
  8409 recommended to convert to these new commands using isatool fixgoal
  8410 (backup your sources first!);
  8411 
  8412 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  8413 the current theory context, and 'theory' to lookup stored theories;
  8414 
  8415 * new theory section 'locale' for declaring constants, assumptions and
  8416 definitions that have local scope;
  8417 
  8418 * new theory section 'nonterminals' for purely syntactic types;
  8419 
  8420 * new theory section 'setup' for generic ML setup functions
  8421 (e.g. package initialization);
  8422 
  8423 * the distribution now includes Isabelle icons: see
  8424 lib/logo/isabelle-{small,tiny}.xpm;
  8425 
  8426 * isatool install - install binaries with absolute references to
  8427 ISABELLE_HOME/bin;
  8428 
  8429 * isatool logo -- create instances of the Isabelle logo (as EPS);
  8430 
  8431 * print mode 'emacs' reserved for Isamode;
  8432 
  8433 * support multiple print (ast) translations per constant name;
  8434 
  8435 * theorems involving oracles are now printed with a suffixed [!];
  8436 
  8437 
  8438 *** HOL ***
  8439 
  8440 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  8441 
  8442 * HOL/inductive package reorganized and improved: now supports mutual
  8443 definitions such as
  8444 
  8445   inductive EVEN ODD
  8446     intrs
  8447       null "0 : EVEN"
  8448       oddI "n : EVEN ==> Suc n : ODD"
  8449       evenI "n : ODD ==> Suc n : EVEN"
  8450 
  8451 new theorem list "elims" contains an elimination rule for each of the
  8452 recursive sets; inductive definitions now handle disjunctive premises
  8453 correctly (also ZF);
  8454 
  8455 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  8456 "mutual_induct" no longer exists - the induction rule is always
  8457 contained in "induct";
  8458 
  8459 
  8460 * HOL/datatype package re-implemented and greatly improved: now
  8461 supports mutually recursive datatypes such as
  8462 
  8463   datatype
  8464     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  8465             | SUM ('a aexp) ('a aexp)
  8466             | DIFF ('a aexp) ('a aexp)
  8467             | NUM 'a
  8468   and
  8469     'a bexp = LESS ('a aexp) ('a aexp)
  8470             | AND ('a bexp) ('a bexp)
  8471             | OR ('a bexp) ('a bexp)
  8472 
  8473 as well as indirectly recursive datatypes such as
  8474 
  8475   datatype
  8476     ('a, 'b) term = Var 'a
  8477                   | App 'b ((('a, 'b) term) list)
  8478 
  8479 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  8480 induction on mutually / indirectly recursive datatypes.
  8481 
  8482 Primrec equations are now stored in theory and can be accessed via
  8483 <function_name>.simps.
  8484 
  8485 INCOMPATIBILITIES:
  8486 
  8487   - Theories using datatypes must now have theory Datatype as an
  8488     ancestor.
  8489   - The specific <typename>.induct_tac no longer exists - use the
  8490     generic induct_tac instead.
  8491   - natE has been renamed to nat.exhaust - use exhaust_tac
  8492     instead of res_inst_tac ... natE. Note that the variable
  8493     names in nat.exhaust differ from the names in natE, this
  8494     may cause some "fragile" proofs to fail.
  8495   - The theorems split_<typename>_case and split_<typename>_case_asm
  8496     have been renamed to <typename>.split and <typename>.split_asm.
  8497   - Since default sorts of type variables are now handled correctly,
  8498     some datatype definitions may have to be annotated with explicit
  8499     sort constraints.
  8500   - Primrec definitions no longer require function name and type
  8501     of recursive argument.
  8502 
  8503 Consider using isatool fixdatatype to adapt your theories and proof
  8504 scripts to the new package (backup your sources first!).
  8505 
  8506 
  8507 * HOL/record package: considerably improved implementation; now
  8508 includes concrete syntax for record types, terms, updates; theorems
  8509 for surjective pairing and splitting !!-bound record variables; proof
  8510 support is as follows:
  8511 
  8512   1) standard conversions (selectors or updates applied to record
  8513 constructor terms) are part of the standard simpset;
  8514 
  8515   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  8516 made part of standard simpset and claset via addIffs;
  8517 
  8518   3) a tactic for record field splitting (record_split_tac) is part of
  8519 the standard claset (addSWrapper);
  8520 
  8521 To get a better idea about these rules you may retrieve them via
  8522 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  8523 the name of your record type.
  8524 
  8525 The split tactic 3) conceptually simplifies by the following rule:
  8526 
  8527   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  8528 
  8529 Thus any record variable that is bound by meta-all will automatically
  8530 blow up into some record constructor term, consequently the
  8531 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  8532 solve record problems automatically.
  8533 
  8534 
  8535 * reorganized the main HOL image: HOL/Integ and String loaded by
  8536 default; theory Main includes everything;
  8537 
  8538 * automatic simplification of integer sums and comparisons, using cancellation;
  8539 
  8540 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  8541 
  8542 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  8543 
  8544 * many new identities for unions, intersections, set difference, etc.;
  8545 
  8546 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  8547 called split_if, split_split, split_sum_case and split_nat_case (to go
  8548 with add/delsplits);
  8549 
  8550 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  8551 (?x::unit) = (); this is made part of the default simpset, which COULD
  8552 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  8553 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  8554 unit_abs_eta_conv is added in order to counter the effect of
  8555 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  8556 %u.f();
  8557 
  8558 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  8559 makes more sense);
  8560 
  8561 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8562   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8563   disjointness reasoning but breaking a few old proofs.
  8564 
  8565 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  8566 to 'converse' from 'inverse' (for compatibility with ZF and some
  8567 literature);
  8568 
  8569 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  8570 the well-founded relation;
  8571 
  8572 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8573     Compl A.  The "Compl" syntax remains available as input syntax for this
  8574     release ONLY.
  8575 
  8576 * HOL/Update: new theory of function updates:
  8577     f(a:=b) == %x. if x=a then b else f x
  8578 may also be iterated as in f(a:=b,c:=d,...);
  8579 
  8580 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8581 
  8582 * HOL/List:
  8583   - new function list_update written xs[i:=v] that updates the i-th
  8584     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8585   - new function `upt' written [i..j(] which generates the list
  8586     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8587     bound write [i..j], which is a shorthand for [i..j+1(].
  8588   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8589 
  8590 * HOL/Arith:
  8591   - removed 'pred' (predecessor) function;
  8592   - generalized some theorems about n-1;
  8593   - many new laws about "div" and "mod";
  8594   - new laws about greatest common divisors (see theory ex/Primes);
  8595 
  8596 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8597 instead of "inverse";
  8598 
  8599 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8600   of the multiset ordering;
  8601 
  8602 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8603   (not included by default);
  8604 
  8605 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8606 
  8607 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8608   programs, i.e. different program variables may have different types.
  8609 
  8610 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8611   [previously, this check worked only if the rewrite rule was unconditional]
  8612   Now rew can involve either definitions or equalities (either == or =).
  8613 
  8614 
  8615 *** ZF ***
  8616 
  8617 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8618   only the theorems proved on ZF.ML;
  8619 
  8620 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8621   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8622   disjointness reasoning but breaking a few old proofs.
  8623 
  8624 * ZF/Update: new theory of function updates
  8625     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8626   may also be iterated as in f(a:=b,c:=d,...);
  8627 
  8628 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8629 
  8630 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8631   [previously, this check worked only if the rewrite rule was unconditional]
  8632   Now rew can involve either definitions or equalities (either == or =).
  8633 
  8634 * case_tac provided for compatibility with HOL
  8635     (like the old excluded_middle_tac, but with subgoals swapped)
  8636 
  8637 
  8638 *** Internal programming interfaces ***
  8639 
  8640 * Pure: several new basic modules made available for general use, see
  8641 also src/Pure/README;
  8642 
  8643 * improved the theory data mechanism to support encapsulation (data
  8644 kind name replaced by private Object.kind, acting as authorization
  8645 key); new type-safe user interface via functor TheoryDataFun; generic
  8646 print_data function becomes basically useless;
  8647 
  8648 * removed global_names compatibility flag -- all theory declarations
  8649 are qualified by default;
  8650 
  8651 * module Pure/Syntax now offers quote / antiquote translation
  8652 functions (useful for Hoare logic etc. with implicit dependencies);
  8653 see HOL/ex/Antiquote for an example use;
  8654 
  8655 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8656 cterm -> thm;
  8657 
  8658 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8659 subgoal;
  8660 
  8661 * Display.print_goals function moved to Locale.print_goals;
  8662 
  8663 * standard print function for goals supports current_goals_markers
  8664 variable for marking begin of proof, end of proof, start of goal; the
  8665 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8666 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8667 for example;
  8668 
  8669 
  8670 
  8671 New in Isabelle98 (January 1998)
  8672 --------------------------------
  8673 
  8674 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8675 
  8676 * changed lexical syntax of terms / types: dots made part of long
  8677 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8678 
  8679 * simpset (and claset) reference variable replaced by functions
  8680 simpset / simpset_ref;
  8681 
  8682 * no longer supports theory aliases (via merge) and non-trivial
  8683 implicit merge of thms' signatures;
  8684 
  8685 * most internal names of constants changed due to qualified names;
  8686 
  8687 * changed Pure/Sequence interface (see Pure/seq.ML);
  8688 
  8689 
  8690 *** General Changes ***
  8691 
  8692 * hierachically structured name spaces (for consts, types, axms, thms
  8693 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8694 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8695 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8696 long_names for fully qualified output names; NOTE: ML programs
  8697 (special tactics, packages etc.) referring to internal names may have
  8698 to be adapted to cope with fully qualified names; in case of severe
  8699 backward campatibility problems try setting 'global_names' at compile
  8700 time to have enrything declared within a flat name space; one may also
  8701 fine tune name declarations in theories via the 'global' and 'local'
  8702 section;
  8703 
  8704 * reimplemented the implicit simpset and claset using the new anytype
  8705 data filed in signatures; references simpset:simpset ref etc. are
  8706 replaced by functions simpset:unit->simpset and
  8707 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8708 to patch your ML files accordingly;
  8709 
  8710 * HTML output now includes theory graph data for display with Java
  8711 applet or isatool browser; data generated automatically via isatool
  8712 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8713 
  8714 * defs may now be conditional; improved rewrite_goals_tac to handle
  8715 conditional equations;
  8716 
  8717 * defs now admits additional type arguments, using TYPE('a) syntax;
  8718 
  8719 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8720 creates a new theory node; implicit merge of thms' signatures is
  8721 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8722 transfer:theory->thm->thm in (rare) cases;
  8723 
  8724 * improved handling of draft signatures / theories; draft thms (and
  8725 ctyps, cterms) are automatically promoted to real ones;
  8726 
  8727 * slightly changed interfaces for oracles: admit many per theory, named
  8728 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8729 
  8730 * print_goals: optional output of const types (set show_consts and
  8731 show_types);
  8732 
  8733 * improved output of warnings (###) and errors (***);
  8734 
  8735 * subgoal_tac displays a warning if the new subgoal has type variables;
  8736 
  8737 * removed old README and Makefiles;
  8738 
  8739 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8740 
  8741 * removed obsolete init_pps and init_database;
  8742 
  8743 * deleted the obsolete tactical STATE, which was declared by
  8744     fun STATE tacfun st = tacfun st st;
  8745 
  8746 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8747 (which abbreviates $HOME);
  8748 
  8749 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8750 use isatool fixseq to adapt your ML programs (this works for fully
  8751 qualified references to the Sequence structure only!);
  8752 
  8753 * use_thy no longer requires writable current directory; it always
  8754 reloads .ML *and* .thy file, if either one is out of date;
  8755 
  8756 
  8757 *** Classical Reasoner ***
  8758 
  8759 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8760 tactics that use classical reasoning to simplify a subgoal without
  8761 splitting it into several subgoals;
  8762 
  8763 * Safe_tac: like safe_tac but uses the default claset;
  8764 
  8765 
  8766 *** Simplifier ***
  8767 
  8768 * added simplification meta rules:
  8769     (asm_)(full_)simplify: simpset -> thm -> thm;
  8770 
  8771 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8772 logics (again);
  8773 
  8774 * added prems argument to simplification procedures;
  8775 
  8776 * HOL, FOL, ZF: added infix function `addsplits':
  8777   instead of `<simpset> setloop (split_tac <thms>)'
  8778   you can simply write `<simpset> addsplits <thms>'
  8779 
  8780 
  8781 *** Syntax ***
  8782 
  8783 * TYPE('a) syntax for type reflection terms;
  8784 
  8785 * no longer handles consts with name "" -- declare as 'syntax' instead;
  8786 
  8787 * pretty printer: changed order of mixfix annotation preference (again!);
  8788 
  8789 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  8790 
  8791 
  8792 *** HOL ***
  8793 
  8794 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8795   with `addloop' of the simplifier to faciliate case splitting in premises.
  8796 
  8797 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  8798 
  8799 * HOL/Auth: new protocol proofs including some for the Internet
  8800   protocol TLS;
  8801 
  8802 * HOL/Map: new theory of `maps' a la VDM;
  8803 
  8804 * HOL/simplifier: simplification procedures nat_cancel_sums for
  8805 cancelling out common nat summands from =, <, <= (in)equalities, or
  8806 differences; simplification procedures nat_cancel_factor for
  8807 cancelling common factor from =, <, <= (in)equalities over natural
  8808 sums; nat_cancel contains both kinds of procedures, it is installed by
  8809 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  8810 
  8811 * HOL/simplifier: terms of the form
  8812   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  8813   are rewritten to
  8814   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  8815   and those of the form
  8816   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  8817   are rewritten to
  8818   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  8819 
  8820 * HOL/datatype
  8821   Each datatype `t' now comes with a theorem `split_t_case' of the form
  8822 
  8823   P(t_case f1 ... fn x) =
  8824      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  8825         ...
  8826        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  8827      )
  8828 
  8829   and a theorem `split_t_case_asm' of the form
  8830 
  8831   P(t_case f1 ... fn x) =
  8832     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  8833         ...
  8834        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  8835      )
  8836   which can be added to a simpset via `addsplits'. The existing theorems
  8837   expand_list_case and expand_option_case have been renamed to
  8838   split_list_case and split_option_case.
  8839 
  8840 * HOL/Arithmetic:
  8841   - `pred n' is automatically converted to `n-1'.
  8842     Users are strongly encouraged not to use `pred' any longer,
  8843     because it will disappear altogether at some point.
  8844   - Users are strongly encouraged to write "0 < n" rather than
  8845     "n ~= 0". Theorems and proof tools have been modified towards this
  8846     `standard'.
  8847 
  8848 * HOL/Lists:
  8849   the function "set_of_list" has been renamed "set" (and its theorems too);
  8850   the function "nth" now takes its arguments in the reverse order and
  8851   has acquired the infix notation "!" as in "xs!n".
  8852 
  8853 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  8854 
  8855 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  8856   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  8857 
  8858 * HOL/record: extensible records with schematic structural subtyping
  8859 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  8860 still lacks various theorems and concrete record syntax;
  8861 
  8862 
  8863 *** HOLCF ***
  8864 
  8865 * removed "axioms" and "generated by" sections;
  8866 
  8867 * replaced "ops" section by extended "consts" section, which is capable of
  8868   handling the continuous function space "->" directly;
  8869 
  8870 * domain package:
  8871   . proves theorems immediately and stores them in the theory,
  8872   . creates hierachical name space,
  8873   . now uses normal mixfix annotations (instead of cinfix...),
  8874   . minor changes to some names and values (for consistency),
  8875   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  8876   . separator between mutual domain defs: changed "," to "and",
  8877   . improved handling of sort constraints;  now they have to
  8878     appear on the left-hand side of the equations only;
  8879 
  8880 * fixed LAM <x,y,zs>.b syntax;
  8881 
  8882 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  8883 adm (%x. P (t x)), where P is chainfinite and t continuous;
  8884 
  8885 
  8886 *** FOL and ZF ***
  8887 
  8888 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8889   with `addloop' of the simplifier to faciliate case splitting in premises.
  8890 
  8891 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  8892 in HOL, they strip ALL and --> from proved theorems;
  8893 
  8894 
  8895 
  8896 New in Isabelle94-8 (May 1997)
  8897 ------------------------------
  8898 
  8899 *** General Changes ***
  8900 
  8901 * new utilities to build / run / maintain Isabelle etc. (in parts
  8902 still somewhat experimental); old Makefiles etc. still functional;
  8903 
  8904 * new 'Isabelle System Manual';
  8905 
  8906 * INSTALL text, together with ./configure and ./build scripts;
  8907 
  8908 * reimplemented type inference for greater efficiency, better error
  8909 messages and clean internal interface;
  8910 
  8911 * prlim command for dealing with lots of subgoals (an easier way of
  8912 setting goals_limit);
  8913 
  8914 
  8915 *** Syntax ***
  8916 
  8917 * supports alternative (named) syntax tables (parser and pretty
  8918 printer); internal interface is provided by add_modesyntax(_i);
  8919 
  8920 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  8921 be used in conjunction with the Isabelle symbol font; uses the
  8922 "symbols" syntax table;
  8923 
  8924 * added token_translation interface (may translate name tokens in
  8925 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  8926 the current print_mode); IMPORTANT: user print translation functions
  8927 are responsible for marking newly introduced bounds
  8928 (Syntax.mark_boundT);
  8929 
  8930 * token translations for modes "xterm" and "xterm_color" that display
  8931 names in bold, underline etc. or colors (which requires a color
  8932 version of xterm);
  8933 
  8934 * infixes may now be declared with names independent of their syntax;
  8935 
  8936 * added typed_print_translation (like print_translation, but may
  8937 access type of constant);
  8938 
  8939 
  8940 *** Classical Reasoner ***
  8941 
  8942 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  8943 some limitations.  Blast_tac...
  8944   + ignores addss, addbefore, addafter; this restriction is intrinsic
  8945   + ignores elimination rules that don't have the correct format
  8946         (the conclusion MUST be a formula variable)
  8947   + ignores types, which can make HOL proofs fail
  8948   + rules must not require higher-order unification, e.g. apply_type in ZF
  8949     [message "Function Var's argument not a bound variable" relates to this]
  8950   + its proof strategy is more general but can actually be slower
  8951 
  8952 * substitution with equality assumptions no longer permutes other
  8953 assumptions;
  8954 
  8955 * minor changes in semantics of addafter (now called addaltern); renamed
  8956 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  8957 (and access functions for it);
  8958 
  8959 * improved combination of classical reasoner and simplifier:
  8960   + functions for handling clasimpsets
  8961   + improvement of addss: now the simplifier is called _after_ the
  8962     safe steps.
  8963   + safe variant of addss called addSss: uses safe simplifications
  8964     _during_ the safe steps. It is more complete as it allows multiple
  8965     instantiations of unknowns (e.g. with slow_tac).
  8966 
  8967 *** Simplifier ***
  8968 
  8969 * added interface for simplification procedures (functions that
  8970 produce *proven* rewrite rules on the fly, depending on current
  8971 redex);
  8972 
  8973 * ordering on terms as parameter (used for ordered rewriting);
  8974 
  8975 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  8976 
  8977 * the solver is now split into a safe and an unsafe part.
  8978 This should be invisible for the normal user, except that the
  8979 functions setsolver and addsolver have been renamed to setSolver and
  8980 addSolver; added safe_asm_full_simp_tac;
  8981 
  8982 
  8983 *** HOL ***
  8984 
  8985 * a generic induction tactic `induct_tac' which works for all datatypes and
  8986 also for type `nat';
  8987 
  8988 * a generic case distinction tactic `exhaust_tac' which works for all
  8989 datatypes and also for type `nat';
  8990 
  8991 * each datatype comes with a function `size';
  8992 
  8993 * patterns in case expressions allow tuple patterns as arguments to
  8994 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  8995 
  8996 * primrec now also works with type nat;
  8997 
  8998 * recdef: a new declaration form, allows general recursive functions to be
  8999 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  9000 
  9001 * the constant for negation has been renamed from "not" to "Not" to
  9002 harmonize with FOL, ZF, LK, etc.;
  9003 
  9004 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  9005 infinite lists;
  9006 
  9007 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  9008 
  9009 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  9010 problems in commutative rings, using axiomatic type classes for + and *;
  9011 
  9012 * more examples in HOL/MiniML and HOL/Auth;
  9013 
  9014 * more default rewrite rules for quantifiers, union/intersection;
  9015 
  9016 * a new constant `arbitrary == @x.False';
  9017 
  9018 * HOLCF/IOA replaces old HOL/IOA;
  9019 
  9020 * HOLCF changes: derived all rules and arities
  9021   + axiomatic type classes instead of classes
  9022   + typedef instead of faking type definitions
  9023   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  9024   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  9025   + eliminated the types void, one, tr
  9026   + use unit lift and bool lift (with translations) instead of one and tr
  9027   + eliminated blift from Lift3.thy (use Def instead of blift)
  9028   all eliminated rules are derived as theorems --> no visible changes ;
  9029 
  9030 
  9031 *** ZF ***
  9032 
  9033 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  9034 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  9035 as ZF_cs addSIs [equalityI];
  9036 
  9037 
  9038 
  9039 New in Isabelle94-7 (November 96)
  9040 ---------------------------------
  9041 
  9042 * allowing negative levels (as offsets) in prlev and choplev;
  9043 
  9044 * super-linear speedup for large simplifications;
  9045 
  9046 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  9047 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  9048 FAIL); can suppress it using the command Delsimps (ex_simps @
  9049 all_simps); De Morgan laws are also now included, by default;
  9050 
  9051 * improved printing of ==>  :  ~:
  9052 
  9053 * new object-logic "Sequents" adds linear logic, while replacing LK
  9054 and Modal (thanks to Sara Kalvala);
  9055 
  9056 * HOL/Auth: correctness proofs for authentication protocols;
  9057 
  9058 * HOL: new auto_tac combines rewriting and classical reasoning (many
  9059 examples on HOL/Auth);
  9060 
  9061 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  9062 the rewriter and classical reasoner simultaneously;
  9063 
  9064 * function uresult no longer returns theorems in "standard" format;
  9065 regain previous version by: val uresult = standard o uresult;
  9066 
  9067 
  9068 
  9069 New in Isabelle94-6
  9070 -------------------
  9071 
  9072 * oracles -- these establish an interface between Isabelle and trusted
  9073 external reasoners, which may deliver results as theorems;
  9074 
  9075 * proof objects (in particular record all uses of oracles);
  9076 
  9077 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  9078 
  9079 * "constdefs" section in theory files;
  9080 
  9081 * "primrec" section (HOL) no longer requires names;
  9082 
  9083 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  9084 
  9085 
  9086 
  9087 New in Isabelle94-5
  9088 -------------------
  9089 
  9090 * reduced space requirements;
  9091 
  9092 * automatic HTML generation from theories;
  9093 
  9094 * theory files no longer require "..." (quotes) around most types;
  9095 
  9096 * new examples, including two proofs of the Church-Rosser theorem;
  9097 
  9098 * non-curried (1994) version of HOL is no longer distributed;
  9099 
  9100 
  9101 
  9102 New in Isabelle94-4
  9103 -------------------
  9104 
  9105 * greatly reduced space requirements;
  9106 
  9107 * theory files (.thy) no longer require \...\ escapes at line breaks;
  9108 
  9109 * searchable theorem database (see the section "Retrieving theorems" on
  9110 page 8 of the Reference Manual);
  9111 
  9112 * new examples, including Grabczewski's monumental case study of the
  9113 Axiom of Choice;
  9114 
  9115 * The previous version of HOL renamed to Old_HOL;
  9116 
  9117 * The new version of HOL (previously called CHOL) uses a curried syntax
  9118 for functions.  Application looks like f a b instead of f(a,b);
  9119 
  9120 * Mutually recursive inductive definitions finally work in HOL;
  9121 
  9122 * In ZF, pattern-matching on tuples is now available in all abstractions and
  9123 translates to the operator "split";
  9124 
  9125 
  9126 
  9127 New in Isabelle94-3
  9128 -------------------
  9129 
  9130 * new infix operator, addss, allowing the classical reasoner to
  9131 perform simplification at each step of its search.  Example:
  9132         fast_tac (cs addss ss)
  9133 
  9134 * a new logic, CHOL, the same as HOL, but with a curried syntax
  9135 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  9136 look like (a,b) instead of <a,b>;
  9137 
  9138 * PLEASE NOTE: CHOL will eventually replace HOL!
  9139 
  9140 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  9141 It translates to the operator "split".  A new theory of integers is available;
  9142 
  9143 * In ZF, integer numerals now denote two's-complement binary integers.
  9144 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  9145 
  9146 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  9147 of the Axiom of Choice;
  9148 
  9149 
  9150 
  9151 New in Isabelle94-2
  9152 -------------------
  9153 
  9154 * Significantly faster resolution;
  9155 
  9156 * the different sections in a .thy file can now be mixed and repeated
  9157 freely;
  9158 
  9159 * Database of theorems for FOL, HOL and ZF.  New
  9160 commands including qed, qed_goal and bind_thm store theorems in the database.
  9161 
  9162 * Simple database queries: return a named theorem (get_thm) or all theorems of
  9163 a given theory (thms_of), or find out what theory a theorem was proved in
  9164 (theory_of_thm);
  9165 
  9166 * Bugs fixed in the inductive definition and datatype packages;
  9167 
  9168 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  9169 and HOL_dup_cs obsolete;
  9170 
  9171 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  9172 have been removed;
  9173 
  9174 * Simpler definition of function space in ZF;
  9175 
  9176 * new results about cardinal and ordinal arithmetic in ZF;
  9177 
  9178 * 'subtype' facility in HOL for introducing new types as subsets of existing
  9179 types;
  9180 
  9181 :mode=text:wrap=hard:maxLineLen=72: