NEWS
author haftmann
Wed, 18 Apr 2012 20:40:52 +0200
changeset 48416 ddbcdf538132
parent 48415 d19ce7f40d78
child 48417 fd5bd1ea2570
permissions -rw-r--r--
grouped NEWS concerning relations together
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in Isabelle2012 (May 2012)
     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 
    51 *** Pure ***
    52 
    53 * Auxiliary contexts indicate block structure for specifications with
    54 additional parameters and assumptions.  Such unnamed contexts may be
    55 nested within other targets, like 'theory', 'locale', 'class',
    56 'instantiation' etc.  Results from the local context are generalized
    57 accordingly and applied to the enclosing target context.  Example:
    58 
    59   context
    60     fixes x y z :: 'a
    61     assumes xy: "x = y" and yz: "y = z"
    62   begin
    63 
    64   lemma my_trans: "x = z" using xy yz by simp
    65 
    66   end
    67 
    68   thm my_trans
    69 
    70 The most basic application is to factor-out context elements of
    71 several fixes/assumes/shows theorem statements, e.g. see
    72 ~~/src/HOL/Isar_Examples/Group_Context.thy
    73 
    74 Any other local theory specification element works within the "context
    75 ... begin ... end" block as well.
    76 
    77 * Bundled declarations associate attributed fact expressions with a
    78 given name in the context.  These may be later included in other
    79 contexts.  This allows to manage context extensions casually, without
    80 the logical dependencies of locales and locale interpretation.
    81 
    82 See commands 'bundle', 'include', 'including' etc. in the isar-ref
    83 manual.
    84 
    85 * Rule composition via attribute "OF" (or ML functions OF/MRS) is more
    86 tolerant against multiple unifiers, as long as the final result is
    87 unique.  (As before, rules are composed in canonical right-to-left
    88 order to accommodate newly introduced premises.)
    89 
    90 * Command 'definition' no longer exports the foundational "raw_def"
    91 into the user context.  Minor INCOMPATIBILITY, may use the regular
    92 "def" result with attribute "abs_def" to imitate the old version.
    93 
    94 * Attribute "abs_def" turns an equation of the form "f x y == t" into
    95 "f == %x y. t", which ensures that "simp" or "unfold" steps always
    96 expand it.  This also works for object-logic equality.  (Formerly
    97 undocumented feature.)
    98 
    99 * Discontinued old "prems" fact, which used to refer to the accidental
   100 collection of foundational premises in the context (already marked as
   101 legacy since Isabelle2011).
   102 
   103 * Obsolete command 'types' has been discontinued.  Use 'type_synonym'
   104 instead.  INCOMPATIBILITY.
   105 
   106 * Old code generator for SML and its commands 'code_module',
   107 'code_library', 'consts_code', 'types_code' have been discontinued.
   108 Use commands of the generic code generator instead.  INCOMPATIBILITY.
   109 
   110 * Redundant attribute "code_inline" has been discontinued. Use
   111 "code_unfold" instead.  INCOMPATIBILITY.
   112 
   113 * Dropped attribute "code_unfold_post" in favor of the its dual
   114 "code_abbrev", which yields a common pattern in definitions like
   115 
   116   definition [code_abbrev]: "f = t"
   117 
   118 INCOMPATIBILITY.
   119 
   120 * Sort constraints are now propagated in simultaneous statements, just
   121 like type constraints.  INCOMPATIBILITY in rare situations, where
   122 distinct sorts used to be assigned accidentally.  For example:
   123 
   124   lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"
   125 
   126   lemma "P (x::'a)" and "Q (y::'a::bar)"
   127     -- "now uniform 'a::bar instead of default sort for first occurrence (!)"
   128 
   129 
   130 *** HOL ***
   131 
   132 * New tutorial "Programming and Proving in Isabelle/HOL" ("prog-prove").
   133 It completely supercedes "A Tutorial Introduction to Structured Isar Proofs",
   134 which has been removed. It supercedes "Isabelle/HOL, A Proof Assistant
   135 for Higher-Order Logic" as the recommended beginners tutorial
   136 but does not cover all of the material of that old tutorial.
   137 
   138 * Discontinued old Tutorial on Isar ("isar-overview");
   139 
   140 * Type 'a set is now a proper type constructor (just as before
   141 Isabelle2008).  Definitions mem_def and Collect_def have disappeared.
   142 Non-trivial INCOMPATIBILITY.  For developments keeping predicates and
   143 sets separate, it is often sufficient to rephrase sets S accidentally
   144 used as predicates by "%x. x : S" and predicates P accidentally used
   145 as sets by "{x. P x}".  Corresponding proofs in a first step should be
   146 pruned from any tinkering with former theorems mem_def and Collect_def
   147 as far as possible.
   148 
   149 For developments which deliberately mixed predicates and sets, a
   150 planning step is necessary to determine what should become a predicate
   151 and what a set.  It can be helpful to carry out that step in
   152 Isabelle2011-1 before jumping right into the current release.
   153 
   154 * The representation of numerals has changed.  Datatype "num"
   155 represents strictly positive binary numerals, along with functions
   156 "numeral :: num => 'a" and "neg_numeral :: num => 'a" to represent
   157 positive and negated numeric literals, respectively. (See definitions
   158 in ~~/src/HOL/Num.thy.) Potential INCOMPATIBILITY, some user theories
   159 may require adaptations as follows:
   160 
   161   - Theorems with number_ring or number_semiring constraints: These
   162     classes are gone; use comm_ring_1 or comm_semiring_1 instead.
   163 
   164   - Theories defining numeric types: Remove number, number_semiring,
   165     and number_ring instances. Defer all theorems about numerals until
   166     after classes one and semigroup_add have been instantiated.
   167 
   168   - Numeral-only simp rules: Replace each rule having a "number_of v"
   169     pattern with two copies, one for numeral and one for neg_numeral.
   170 
   171   - Theorems about subclasses of semiring_1 or ring_1: These classes
   172     automatically support numerals now, so more simp rules and
   173     simprocs may now apply within the proof.
   174 
   175   - Definitions and theorems using old constructors Pls/Min/Bit0/Bit1:
   176     Redefine using other integer operations.
   177 
   178 * Code generation by default implements sets as container type rather
   179 than predicates.  INCOMPATIBILITY.
   180 
   181 * New proof import from HOL Light: Faster, simpler, and more scalable.
   182 Requires a proof bundle, which is available as an external component.
   183 Discontinued old (and mostly dead) Importer for HOL4 and HOL Light.
   184 INCOMPATIBILITY.
   185 
   186 * New type synonym 'a rel = ('a * 'a) set
   187 
   188 * More default pred/set conversions on a couple of relation operations
   189 and predicates.  Added powers of predicate relations.  Consolidation
   190 of some relation theorems:
   191 
   192   converse_def ~> converse_unfold
   193   rel_comp_def ~> relcomp_unfold
   194   symp_def ~> (dropped, use symp_def and sym_def instead)
   195   transp_def ~> transp_trans
   196   Domain_def ~> Domain_unfold
   197   Range_def ~> Domain_converse [symmetric]
   198 
   199 Generalized theorems INF_INT_eq, INF_INT_eq2, SUP_UN_eq, SUP_UN_eq2.
   200 
   201 See theory "Relation" for examples for making use of pred/set
   202 conversions by means of attributes "to_set" and "to_pred".
   203 
   204 INCOMPATIBILITY.
   205 
   206 * Renamed facts about the power operation on relations, i.e., relpow
   207 to match the constant's name:
   208 
   209   rel_pow_1 ~> relpow_1
   210   rel_pow_0_I ~> relpow_0_I
   211   rel_pow_Suc_I ~> relpow_Suc_I
   212   rel_pow_Suc_I2 ~> relpow_Suc_I2
   213   rel_pow_0_E ~> relpow_0_E
   214   rel_pow_Suc_E ~> relpow_Suc_E
   215   rel_pow_E ~> relpow_E
   216   rel_pow_Suc_D2 ~> relpow_Suc_D2
   217   rel_pow_Suc_E2 ~> relpow_Suc_E2
   218   rel_pow_Suc_D2' ~> relpow_Suc_D2'
   219   rel_pow_E2 ~> relpow_E2
   220   rel_pow_add ~> relpow_add
   221   rel_pow_commute ~> relpow
   222   rel_pow_empty ~> relpow_empty:
   223   rtrancl_imp_UN_rel_pow ~> rtrancl_imp_UN_relpow
   224   rel_pow_imp_rtrancl ~> relpow_imp_rtrancl
   225   rtrancl_is_UN_rel_pow ~> rtrancl_is_UN_relpow
   226   rtrancl_imp_rel_pow ~> rtrancl_imp_relpow
   227   rel_pow_fun_conv ~> relpow_fun_conv
   228   rel_pow_finite_bounded1 ~> relpow_finite_bounded1
   229   rel_pow_finite_bounded ~> relpow_finite_bounded
   230   rtrancl_finite_eq_rel_pow ~> rtrancl_finite_eq_relpow
   231   trancl_finite_eq_rel_pow ~> trancl_finite_eq_relpow
   232   single_valued_rel_pow ~> single_valued_relpow
   233 
   234 INCOMPATIBILITY.
   235 
   236 * Theory Relation: Consolidated constant name for relation composition
   237 and corresponding theorem names:
   238 
   239   - Renamed constant rel_comp to relcomp.
   240 
   241   - Dropped abbreviation pred_comp. Use relcompp instead.
   242 
   243   - Renamed theorems:
   244 
   245     rel_compI ~> relcompI
   246     rel_compEpair ~> relcompEpair
   247     rel_compE ~> relcompE
   248     pred_comp_rel_comp_eq ~> relcompp_relcomp_eq
   249     rel_comp_empty1 ~> relcomp_empty1
   250     rel_comp_mono ~> relcomp_mono
   251     rel_comp_subset_Sigma ~> relcomp_subset_Sigma
   252     rel_comp_distrib ~> relcomp_distrib
   253     rel_comp_distrib2 ~> relcomp_distrib2
   254     rel_comp_UNION_distrib ~> relcomp_UNION_distrib
   255     rel_comp_UNION_distrib2 ~> relcomp_UNION_distrib2
   256     single_valued_rel_comp ~> single_valued_relcomp
   257     rel_comp_def ~> relcomp_unfold
   258     converse_rel_comp ~> converse_relcomp
   259     pred_compI ~> relcomppI
   260     pred_compE ~> relcomppE
   261     pred_comp_bot1 ~> relcompp_bot1
   262     pred_comp_bot2 ~> relcompp_bot2
   263     transp_pred_comp_less_eq ~> transp_relcompp_less_eq
   264     pred_comp_mono ~> relcompp_mono
   265     pred_comp_distrib ~> relcompp_distrib
   266     pred_comp_distrib2 ~> relcompp_distrib2
   267     converse_pred_comp ~> converse_relcompp
   268 
   269     finite_rel_comp ~> finite_relcomp
   270 
   271     set_rel_comp ~> set_relcomp
   272 
   273 INCOMPATIBILITY.
   274 
   275 * Theory Divides: Discontinued redundant theorems about div and mod.
   276 INCOMPATIBILITY, use the corresponding generic theorems instead.
   277 
   278   DIVISION_BY_ZERO ~> div_by_0, mod_by_0
   279   zdiv_self ~> div_self
   280   zmod_self ~> mod_self
   281   zdiv_zero ~> div_0
   282   zmod_zero ~> mod_0
   283   zdiv_zmod_equality ~> div_mod_equality2
   284   zdiv_zmod_equality2 ~> div_mod_equality
   285   zmod_zdiv_trivial ~> mod_div_trivial
   286   zdiv_zminus_zminus ~> div_minus_minus
   287   zmod_zminus_zminus ~> mod_minus_minus
   288   zdiv_zminus2 ~> div_minus_right
   289   zmod_zminus2 ~> mod_minus_right
   290   zdiv_minus1_right ~> div_minus1_right
   291   zmod_minus1_right ~> mod_minus1_right
   292   zdvd_mult_div_cancel ~> dvd_mult_div_cancel
   293   zmod_zmult1_eq ~> mod_mult_right_eq
   294   zpower_zmod ~> power_mod
   295   zdvd_zmod ~> dvd_mod
   296   zdvd_zmod_imp_zdvd ~> dvd_mod_imp_dvd
   297   mod_mult_distrib ~> mult_mod_left
   298   mod_mult_distrib2 ~> mult_mod_right
   299 
   300 * Removed redundant theorems nat_mult_2 and nat_mult_2_right; use
   301 generic mult_2 and mult_2_right instead. INCOMPATIBILITY.
   302 
   303 * Consolidated various theorem names relating to Finite_Set.fold
   304 combinator:
   305 
   306   inf_INFI_fold_inf ~> inf_INF_fold_inf
   307   sup_SUPR_fold_sup ~> sup_SUP_fold_sup
   308   INFI_fold_inf ~> INF_fold_inf
   309   SUPR_fold_sup ~> SUP_fold_sup
   310   union_set ~> union_set_fold
   311   minus_set ~> minus_set_fold
   312 
   313 INCOMPATIBILITY.
   314 
   315 * Consolidated theorem names concerning fold combinators:
   316 
   317   INFI_set_fold ~> INF_set_fold
   318   SUPR_set_fold ~> SUP_set_fold
   319   INF_code ~> INF_set_foldr
   320   SUP_code ~> SUP_set_foldr
   321   foldr.simps ~> foldr.simps (in point-free formulation)
   322   foldr_fold_rev ~> foldr_conv_fold
   323   foldl_fold ~> foldl_conv_fold
   324   foldr_foldr ~> foldr_conv_foldl
   325   foldl_foldr ~> foldl_conv_foldr
   326 
   327 INCOMPATIBILITY.
   328 
   329 * Dropped rarely useful theorems concerning fold combinators:
   330 foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
   331 rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
   332 concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
   333 foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
   334 listsum_conv_fold, listsum_foldl, sort_foldl_insort, foldl_assoc,
   335 foldr_conv_foldl, start_le_sum, elem_le_sum, sum_eq_0_conv.
   336 INCOMPATIBILITY.  For the common phrases "%xs. List.foldr plus xs 0"
   337 and "List.foldl plus 0", prefer "List.listsum".  Otherwise it can be
   338 useful to boil down "List.foldr" and "List.foldl" to "List.fold" by
   339 unfolding "foldr_conv_fold" and "foldl_conv_fold".
   340 
   341 * Dropped lemmas minus_set_foldr, union_set_foldr, union_coset_foldr,
   342 inter_coset_foldr, Inf_fin_set_foldr, Sup_fin_set_foldr,
   343 Min_fin_set_foldr, Max_fin_set_foldr, Inf_set_foldr, Sup_set_foldr,
   344 INF_set_foldr, SUP_set_foldr.  INCOMPATIBILITY.  Prefer corresponding
   345 lemmas over fold rather than foldr, or make use of lemmas
   346 fold_conv_foldr and fold_rev.
   347 
   348 * Congruence rules Option.map_cong and Option.bind_cong for recursion
   349 through option types.
   350 
   351 * Concrete syntax for case expressions includes constraints for source
   352 positions, and thus produces Prover IDE markup for its bindings.
   353 INCOMPATIBILITY for old-style syntax translations that augment the
   354 pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of
   355 one_case.
   356 
   357 * Discontinued configuration option "syntax_positions": atomic terms
   358 in parse trees are always annotated by position constraints.
   359 
   360 * Finite_Set.fold now qualified.  INCOMPATIBILITY.
   361 
   362 * Renamed some facts on canonical fold on lists, in order to avoid
   363 problems with interpretation involving corresponding facts on foldl
   364 with the same base names:
   365 
   366   fold_set_remdups ~> fold_set_fold_remdups
   367   fold_set ~> fold_set_fold
   368   fold1_set ~> fold1_set_fold
   369 
   370 INCOMPATIBILITY.
   371 
   372 * New theory HOL/Library/DAList provides an abstract type for
   373 association lists with distinct keys.
   374 
   375 * 'datatype' specifications allow explicit sort constraints.
   376 
   377 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
   378 use theory HOL/Library/Nat_Bijection instead.
   379 
   380 * Theory HOL/Library/RBT_Impl: Backing implementation of red-black
   381 trees is now inside a type class context.  Names of affected
   382 operations and lemmas have been prefixed by rbt_.  INCOMPATIBILITY for
   383 theories working directly with raw red-black trees, adapt the names as
   384 follows:
   385 
   386   Operations:
   387   bulkload -> rbt_bulkload
   388   del_from_left -> rbt_del_from_left
   389   del_from_right -> rbt_del_from_right
   390   del -> rbt_del
   391   delete -> rbt_delete
   392   ins -> rbt_ins
   393   insert -> rbt_insert
   394   insertw -> rbt_insert_with
   395   insert_with_key -> rbt_insert_with_key
   396   map_entry -> rbt_map_entry
   397   lookup -> rbt_lookup
   398   sorted -> rbt_sorted
   399   tree_greater -> rbt_greater
   400   tree_less -> rbt_less
   401   tree_less_symbol -> rbt_less_symbol
   402   union -> rbt_union
   403   union_with -> rbt_union_with
   404   union_with_key -> rbt_union_with_key
   405 
   406   Lemmas:
   407   balance_left_sorted -> balance_left_rbt_sorted
   408   balance_left_tree_greater -> balance_left_rbt_greater
   409   balance_left_tree_less -> balance_left_rbt_less
   410   balance_right_sorted -> balance_right_rbt_sorted
   411   balance_right_tree_greater -> balance_right_rbt_greater
   412   balance_right_tree_less -> balance_right_rbt_less
   413   balance_sorted -> balance_rbt_sorted
   414   balance_tree_greater -> balance_rbt_greater
   415   balance_tree_less -> balance_rbt_less
   416   bulkload_is_rbt -> rbt_bulkload_is_rbt
   417   combine_sorted -> combine_rbt_sorted
   418   combine_tree_greater -> combine_rbt_greater
   419   combine_tree_less -> combine_rbt_less
   420   delete_in_tree -> rbt_delete_in_tree
   421   delete_is_rbt -> rbt_delete_is_rbt
   422   del_from_left_tree_greater -> rbt_del_from_left_rbt_greater
   423   del_from_left_tree_less -> rbt_del_from_left_rbt_less
   424   del_from_right_tree_greater -> rbt_del_from_right_rbt_greater
   425   del_from_right_tree_less -> rbt_del_from_right_rbt_less
   426   del_in_tree -> rbt_del_in_tree
   427   del_inv1_inv2 -> rbt_del_inv1_inv2
   428   del_sorted -> rbt_del_rbt_sorted
   429   del_tree_greater -> rbt_del_rbt_greater
   430   del_tree_less -> rbt_del_rbt_less
   431   dom_lookup_Branch -> dom_rbt_lookup_Branch
   432   entries_lookup -> entries_rbt_lookup
   433   finite_dom_lookup -> finite_dom_rbt_lookup
   434   insert_sorted -> rbt_insert_rbt_sorted
   435   insertw_is_rbt -> rbt_insertw_is_rbt
   436   insertwk_is_rbt -> rbt_insertwk_is_rbt
   437   insertwk_sorted -> rbt_insertwk_rbt_sorted
   438   insertw_sorted -> rbt_insertw_rbt_sorted
   439   ins_sorted -> ins_rbt_sorted
   440   ins_tree_greater -> ins_rbt_greater
   441   ins_tree_less -> ins_rbt_less
   442   is_rbt_sorted -> is_rbt_rbt_sorted
   443   lookup_balance -> rbt_lookup_balance
   444   lookup_bulkload -> rbt_lookup_rbt_bulkload
   445   lookup_delete -> rbt_lookup_rbt_delete
   446   lookup_Empty -> rbt_lookup_Empty
   447   lookup_from_in_tree -> rbt_lookup_from_in_tree
   448   lookup_in_tree -> rbt_lookup_in_tree
   449   lookup_ins -> rbt_lookup_ins
   450   lookup_insert -> rbt_lookup_rbt_insert
   451   lookup_insertw -> rbt_lookup_rbt_insertw
   452   lookup_insertwk -> rbt_lookup_rbt_insertwk
   453   lookup_keys -> rbt_lookup_keys
   454   lookup_map -> rbt_lookup_map
   455   lookup_map_entry -> rbt_lookup_rbt_map_entry
   456   lookup_tree_greater -> rbt_lookup_rbt_greater
   457   lookup_tree_less -> rbt_lookup_rbt_less
   458   lookup_union -> rbt_lookup_rbt_union
   459   map_entry_color_of -> rbt_map_entry_color_of
   460   map_entry_inv1 -> rbt_map_entry_inv1
   461   map_entry_inv2 -> rbt_map_entry_inv2
   462   map_entry_is_rbt -> rbt_map_entry_is_rbt
   463   map_entry_sorted -> rbt_map_entry_rbt_sorted
   464   map_entry_tree_greater -> rbt_map_entry_rbt_greater
   465   map_entry_tree_less -> rbt_map_entry_rbt_less
   466   map_tree_greater -> map_rbt_greater
   467   map_tree_less -> map_rbt_less
   468   map_sorted -> map_rbt_sorted
   469   paint_sorted -> paint_rbt_sorted
   470   paint_lookup -> paint_rbt_lookup
   471   paint_tree_greater -> paint_rbt_greater
   472   paint_tree_less -> paint_rbt_less
   473   sorted_entries -> rbt_sorted_entries
   474   tree_greater_eq_trans -> rbt_greater_eq_trans
   475   tree_greater_nit -> rbt_greater_nit
   476   tree_greater_prop -> rbt_greater_prop
   477   tree_greater_simps -> rbt_greater_simps
   478   tree_greater_trans -> rbt_greater_trans
   479   tree_less_eq_trans -> rbt_less_eq_trans
   480   tree_less_nit -> rbt_less_nit
   481   tree_less_prop -> rbt_less_prop
   482   tree_less_simps -> rbt_less_simps
   483   tree_less_trans -> rbt_less_trans
   484   tree_ord_props -> rbt_ord_props
   485   union_Branch -> rbt_union_Branch
   486   union_is_rbt -> rbt_union_is_rbt
   487   unionw_is_rbt -> rbt_unionw_is_rbt
   488   unionwk_is_rbt -> rbt_unionwk_is_rbt
   489   unionwk_sorted -> rbt_unionwk_rbt_sorted
   490 
   491 * Session HOL-Word: Discontinued many redundant theorems specific to
   492 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
   493 instead.
   494 
   495   word_sub_alt ~> word_sub_wi
   496   word_add_alt ~> word_add_def
   497   word_mult_alt ~> word_mult_def
   498   word_minus_alt ~> word_minus_def
   499   word_0_alt ~> word_0_wi
   500   word_1_alt ~> word_1_wi
   501   word_add_0 ~> add_0_left
   502   word_add_0_right ~> add_0_right
   503   word_mult_1 ~> mult_1_left
   504   word_mult_1_right ~> mult_1_right
   505   word_add_commute ~> add_commute
   506   word_add_assoc ~> add_assoc
   507   word_add_left_commute ~> add_left_commute
   508   word_mult_commute ~> mult_commute
   509   word_mult_assoc ~> mult_assoc
   510   word_mult_left_commute ~> mult_left_commute
   511   word_left_distrib ~> left_distrib
   512   word_right_distrib ~> right_distrib
   513   word_left_minus ~> left_minus
   514   word_diff_0_right ~> diff_0_right
   515   word_diff_self ~> diff_self
   516   word_sub_def ~> diff_minus
   517   word_diff_minus ~> diff_minus
   518   word_add_ac ~> add_ac
   519   word_mult_ac ~> mult_ac
   520   word_plus_ac0 ~> add_0_left add_0_right add_ac
   521   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
   522   word_order_trans ~> order_trans
   523   word_order_refl ~> order_refl
   524   word_order_antisym ~> order_antisym
   525   word_order_linear ~> linorder_linear
   526   lenw1_zero_neq_one ~> zero_neq_one
   527   word_number_of_eq ~> number_of_eq
   528   word_of_int_add_hom ~> wi_hom_add
   529   word_of_int_sub_hom ~> wi_hom_sub
   530   word_of_int_mult_hom ~> wi_hom_mult
   531   word_of_int_minus_hom ~> wi_hom_neg
   532   word_of_int_succ_hom ~> wi_hom_succ
   533   word_of_int_pred_hom ~> wi_hom_pred
   534   word_of_int_0_hom ~> word_0_wi
   535   word_of_int_1_hom ~> word_1_wi
   536 
   537 * Clarified attribute "mono_set": pure declaration without modifying
   538 the result of the fact expression.
   539 
   540 * "Transitive_Closure.ntrancl": bounded transitive closure on
   541 relations.
   542 
   543 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
   544 
   545 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
   546 
   547 * Theory Int: Discontinued many legacy theorems specific to type int.
   548 INCOMPATIBILITY, use the corresponding generic theorems instead.
   549 
   550   zminus_zminus ~> minus_minus
   551   zminus_0 ~> minus_zero
   552   zminus_zadd_distrib ~> minus_add_distrib
   553   zadd_commute ~> add_commute
   554   zadd_assoc ~> add_assoc
   555   zadd_left_commute ~> add_left_commute
   556   zadd_ac ~> add_ac
   557   zmult_ac ~> mult_ac
   558   zadd_0 ~> add_0_left
   559   zadd_0_right ~> add_0_right
   560   zadd_zminus_inverse2 ~> left_minus
   561   zmult_zminus ~> mult_minus_left
   562   zmult_commute ~> mult_commute
   563   zmult_assoc ~> mult_assoc
   564   zadd_zmult_distrib ~> left_distrib
   565   zadd_zmult_distrib2 ~> right_distrib
   566   zdiff_zmult_distrib ~> left_diff_distrib
   567   zdiff_zmult_distrib2 ~> right_diff_distrib
   568   zmult_1 ~> mult_1_left
   569   zmult_1_right ~> mult_1_right
   570   zle_refl ~> order_refl
   571   zle_trans ~> order_trans
   572   zle_antisym ~> order_antisym
   573   zle_linear ~> linorder_linear
   574   zless_linear ~> linorder_less_linear
   575   zadd_left_mono ~> add_left_mono
   576   zadd_strict_right_mono ~> add_strict_right_mono
   577   zadd_zless_mono ~> add_less_le_mono
   578   int_0_less_1 ~> zero_less_one
   579   int_0_neq_1 ~> zero_neq_one
   580   zless_le ~> less_le
   581   zpower_zadd_distrib ~> power_add
   582   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   583   zero_le_zpower_abs ~> zero_le_power_abs
   584 
   585 * Theory Deriv: Renamed
   586 
   587   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   588 
   589 * New "case_product" attribute to generate a case rule doing multiple
   590 case distinctions at the same time.  E.g.
   591 
   592   list.exhaust [case_product nat.exhaust]
   593 
   594 produces a rule which can be used to perform case distinction on both
   595 a list and a nat.
   596 
   597 * Theory Library/Multiset: Improved code generation of multisets.
   598 
   599 * New diagnostic command 'find_unused_assms' to find potentially
   600 superfluous assumptions in theorems using Quickcheck.
   601 
   602 * Quickcheck:
   603 
   604   - Quickcheck returns variable assignments as counterexamples, which
   605     allows to reveal the underspecification of functions under test.
   606     For example, refuting "hd xs = x", it presents the variable
   607     assignment xs = [] and x = a1 as a counterexample, assuming that
   608     any property is false whenever "hd []" occurs in it.
   609 
   610     These counterexample are marked as potentially spurious, as
   611     Quickcheck also returns "xs = []" as a counterexample to the
   612     obvious theorem "hd xs = hd xs".
   613 
   614     After finding a potentially spurious counterexample, Quickcheck
   615     continues searching for genuine ones.
   616 
   617     By default, Quickcheck shows potentially spurious and genuine
   618     counterexamples. The option "genuine_only" sets quickcheck to only
   619     show genuine counterexamples.
   620 
   621   - The command 'quickcheck_generator' creates random and exhaustive
   622     value generators for a given type and operations.
   623 
   624     It generates values by using the operations as if they were
   625     constructors of that type.
   626 
   627   - Support for multisets.
   628 
   629   - Added "use_subtype" options.
   630 
   631   - Added "quickcheck_locale" configuration to specify how to process
   632     conjectures in a locale context.
   633 
   634 * Nitpick:
   635 
   636   - Fixed infinite loop caused by the 'peephole_optim' option and
   637     affecting 'rat' and 'real'.
   638 
   639 * Sledgehammer:
   640   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   641   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   642   - Renamed "sound" option to "strict".
   643 
   644 * Metis:
   645   - Added possibility to specify lambda translations scheme as a
   646     parenthesized argument (e.g., "by (metis (lifting) ...)").
   647 
   648 * SMT:
   649   - renamed "smt_fixed" option to "smt_read_only_certificates".
   650 
   651 * Command 'try0':
   652   - Renamed from 'try_methods'. INCOMPATIBILITY.
   653 
   654 * New "eventually_elim" method as a generalized variant of the
   655 eventually_elim* rules. Supports structured proofs.
   656 
   657 * HOL/TPTP: support to parse and import TPTP problems (all languages)
   658 into Isabelle/HOL.
   659 
   660 
   661 *** FOL ***
   662 
   663 * New "case_product" attribute (see HOL).
   664 
   665 
   666 *** ZF ***
   667 
   668 * Greater support for structured proofs involving induction or case
   669 analysis.
   670 
   671 * Much greater use of mathematical symbols.
   672 
   673 * Removal of many ML theorem bindings.  INCOMPATIBILITY.
   674 
   675 
   676 *** ML ***
   677 
   678 * Antiquotation @{keyword "name"} produces a parser for outer syntax
   679 from a minor keyword introduced via theory header declaration.
   680 
   681 * Antiquotation @{command_spec "name"} produces the
   682 Outer_Syntax.command_spec from a major keyword introduced via theory
   683 header declaration; it can be passed to Outer_Syntax.command etc.
   684 
   685 * Local_Theory.define no longer hard-wires default theorem name
   686 "foo_def", but retains the binding as given.  If that is Binding.empty
   687 / Attrib.empty_binding, the result is not registered as user-level
   688 fact.  The Local_Theory.define_internal variant allows to specify a
   689 non-empty name (used for the foundation in the background theory),
   690 while omitting the fact binding in the user-context.  Potential
   691 INCOMPATIBILITY for derived definitional packages: need to specify
   692 naming policy for primitive definitions more explicitly.
   693 
   694 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
   695 conformance with similar operations in structure Term and Logic.
   696 
   697 * Antiquotation @{attributes [...]} embeds attribute source
   698 representation into the ML text, which is particularly useful with
   699 declarations like Local_Theory.note.
   700 
   701 * Structure Proof_Context follows standard naming scheme.  Old
   702 ProofContext has been discontinued.  INCOMPATIBILITY.
   703 
   704 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   705 change of semantics: update is applied to auxiliary local theory
   706 context as well.
   707 
   708 * Modernized some old-style infix operations:
   709 
   710   addeqcongs    ~> Simplifier.add_eqcong
   711   deleqcongs    ~> Simplifier.del_eqcong
   712   addcongs      ~> Simplifier.add_cong
   713   delcongs      ~> Simplifier.del_cong
   714   setmksimps    ~> Simplifier.set_mksimps
   715   setmkcong     ~> Simplifier.set_mkcong
   716   setmksym      ~> Simplifier.set_mksym
   717   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   718   settermless   ~> Simplifier.set_termless
   719   setsubgoaler  ~> Simplifier.set_subgoaler
   720   addsplits     ~> Splitter.add_split
   721   delsplits     ~> Splitter.del_split
   722 
   723 
   724 *** System ***
   725 
   726 * ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
   727 (not just JRE).
   728 
   729 * ISABELLE_HOME_WINDOWS refers to ISABELLE_HOME in windows file name
   730 notation, which is useful for the jEdit file browser, for example.
   731 
   732 
   733 
   734 New in Isabelle2011-1 (October 2011)
   735 ------------------------------------
   736 
   737 *** General ***
   738 
   739 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   740 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   741 
   742   - Management of multiple theory files directly from the editor
   743     buffer store -- bypassing the file-system (no requirement to save
   744     files for checking).
   745 
   746   - Markup of formal entities within the text buffer, with semantic
   747     highlighting, tooltips and hyperlinks to jump to defining source
   748     positions.
   749 
   750   - Improved text rendering, with sub/superscripts in the source
   751     buffer (including support for copy/paste wrt. output panel, HTML
   752     theory output and other non-Isabelle text boxes).
   753 
   754   - Refined scheduling of proof checking and printing of results,
   755     based on interactive editor view.  (Note: jEdit folding and
   756     narrowing allows to restrict buffer perspectives explicitly.)
   757 
   758   - Reduced CPU performance requirements, usable on machines with few
   759     cores.
   760 
   761   - Reduced memory requirements due to pruning of unused document
   762     versions (garbage collection).
   763 
   764 See also ~~/src/Tools/jEdit/README.html for further information,
   765 including some remaining limitations.
   766 
   767 * Theory loader: source files are exclusively located via the master
   768 directory of each theory node (where the .thy file itself resides).
   769 The global load path (such as src/HOL/Library) has been discontinued.
   770 Note that the path element ~~ may be used to reference theories in the
   771 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   772 INCOMPATIBILITY.
   773 
   774 * Theory loader: source files are identified by content via SHA1
   775 digests.  Discontinued former path/modtime identification and optional
   776 ISABELLE_FILE_IDENT plugin scripts.
   777 
   778 * Parallelization of nested Isar proofs is subject to
   779 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   780 usedir option -Q.
   781 
   782 * Name space: former unsynchronized references are now proper
   783 configuration options, with more conventional names:
   784 
   785   long_names   ~> names_long
   786   short_names  ~> names_short
   787   unique_names ~> names_unique
   788 
   789 Minor INCOMPATIBILITY, need to declare options in context like this:
   790 
   791   declare [[names_unique = false]]
   792 
   793 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   794 that the result needs to be unique, which means fact specifications
   795 may have to be refined after enriching a proof context.
   796 
   797 * Attribute "case_names" has been refined: the assumptions in each case
   798 can be named now by following the case name with [name1 name2 ...].
   799 
   800 * Isabelle/Isar reference manual has been updated and extended:
   801   - "Synopsis" provides a catalog of main Isar language concepts.
   802   - Formal references in syntax diagrams, via @{rail} antiquotation.
   803   - Updated material from classic "ref" manual, notably about
   804     "Classical Reasoner".
   805 
   806 
   807 *** HOL ***
   808 
   809 * Class bot and top require underlying partial order rather than
   810 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   811 
   812 * Class complete_lattice: generalized a couple of lemmas from sets;
   813 generalized theorems INF_cong and SUP_cong.  New type classes for
   814 complete boolean algebras and complete linear orders.  Lemmas
   815 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   816 class complete_linorder.
   817 
   818 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   819 Sup_fun_def, Inf_apply, Sup_apply.
   820 
   821 Removed redundant lemmas (the right hand side gives hints how to
   822 replace them for (metis ...), or (simp only: ...) proofs):
   823 
   824   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   825   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   826   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   827   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   828   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   829   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   830   Inter_def ~> INF_def, image_def
   831   Union_def ~> SUP_def, image_def
   832   INT_eq ~> INF_def, and image_def
   833   UN_eq ~> SUP_def, and image_def
   834   INF_subset ~> INF_superset_mono [OF _ order_refl]
   835 
   836 More consistent and comprehensive names:
   837 
   838   INTER_eq_Inter_image ~> INF_def
   839   UNION_eq_Union_image ~> SUP_def
   840   INFI_def ~> INF_def
   841   SUPR_def ~> SUP_def
   842   INF_leI ~> INF_lower
   843   INF_leI2 ~> INF_lower2
   844   le_INFI ~> INF_greatest
   845   le_SUPI ~> SUP_upper
   846   le_SUPI2 ~> SUP_upper2
   847   SUP_leI ~> SUP_least
   848   INFI_bool_eq ~> INF_bool_eq
   849   SUPR_bool_eq ~> SUP_bool_eq
   850   INFI_apply ~> INF_apply
   851   SUPR_apply ~> SUP_apply
   852   INTER_def ~> INTER_eq
   853   UNION_def ~> UNION_eq
   854 
   855 INCOMPATIBILITY.
   856 
   857 * Renamed theory Complete_Lattice to Complete_Lattices.
   858 INCOMPATIBILITY.
   859 
   860 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   861 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   862 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   863 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   864 
   865 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   866 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   867 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   868 INCOMPATIBILITY.
   869 
   870 * Added syntactic classes "inf" and "sup" for the respective
   871 constants.  INCOMPATIBILITY: Changes in the argument order of the
   872 (mostly internal) locale predicates for some derived classes.
   873 
   874 * Theorem collections ball_simps and bex_simps do not contain theorems
   875 referring to UNION any longer; these have been moved to collection
   876 UN_ball_bex_simps.  INCOMPATIBILITY.
   877 
   878 * Theory Archimedean_Field: floor now is defined as parameter of a
   879 separate type class floor_ceiling.
   880 
   881 * Theory Finite_Set: more coherent development of fold_set locales:
   882 
   883     locale fun_left_comm ~> locale comp_fun_commute
   884     locale fun_left_comm_idem ~> locale comp_fun_idem
   885 
   886 Both use point-free characterization; interpretation proofs may need
   887 adjustment.  INCOMPATIBILITY.
   888 
   889 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   890 accordance with standard mathematical terminology. INCOMPATIBILITY.
   891 
   892 * Theory Complex_Main: The locale interpretations for the
   893 bounded_linear and bounded_bilinear locales have been removed, in
   894 order to reduce the number of duplicate lemmas. Users must use the
   895 original names for distributivity theorems, potential INCOMPATIBILITY.
   896 
   897   divide.add ~> add_divide_distrib
   898   divide.diff ~> diff_divide_distrib
   899   divide.setsum ~> setsum_divide_distrib
   900   mult.add_right ~> right_distrib
   901   mult.diff_right ~> right_diff_distrib
   902   mult_right.setsum ~> setsum_right_distrib
   903   mult_left.diff ~> left_diff_distrib
   904 
   905 * Theory Complex_Main: Several redundant theorems have been removed or
   906 replaced by more general versions. INCOMPATIBILITY.
   907 
   908   real_diff_def ~> minus_real_def
   909   real_divide_def ~> divide_real_def
   910   real_less_def ~> less_le
   911   real_abs_def ~> abs_real_def
   912   real_sgn_def ~> sgn_real_def
   913   real_mult_commute ~> mult_commute
   914   real_mult_assoc ~> mult_assoc
   915   real_mult_1 ~> mult_1_left
   916   real_add_mult_distrib ~> left_distrib
   917   real_zero_not_eq_one ~> zero_neq_one
   918   real_mult_inverse_left ~> left_inverse
   919   INVERSE_ZERO ~> inverse_zero
   920   real_le_refl ~> order_refl
   921   real_le_antisym ~> order_antisym
   922   real_le_trans ~> order_trans
   923   real_le_linear ~> linear
   924   real_le_eq_diff ~> le_iff_diff_le_0
   925   real_add_left_mono ~> add_left_mono
   926   real_mult_order ~> mult_pos_pos
   927   real_mult_less_mono2 ~> mult_strict_left_mono
   928   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   929   real_0_le_divide_iff ~> zero_le_divide_iff
   930   realpow_two_disj ~> power2_eq_iff
   931   real_squared_diff_one_factored ~> square_diff_one_factored
   932   realpow_two_diff ~> square_diff_square_factored
   933   reals_complete2 ~> complete_real
   934   real_sum_squared_expand ~> power2_sum
   935   exp_ln_eq ~> ln_unique
   936   expi_add ~> exp_add
   937   expi_zero ~> exp_zero
   938   lemma_DERIV_subst ~> DERIV_cong
   939   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   940   LIMSEQ_const ~> tendsto_const
   941   LIMSEQ_norm ~> tendsto_norm
   942   LIMSEQ_add ~> tendsto_add
   943   LIMSEQ_minus ~> tendsto_minus
   944   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   945   LIMSEQ_diff ~> tendsto_diff
   946   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   947   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   948   LIMSEQ_mult ~> tendsto_mult
   949   LIMSEQ_inverse ~> tendsto_inverse
   950   LIMSEQ_divide ~> tendsto_divide
   951   LIMSEQ_pow ~> tendsto_power
   952   LIMSEQ_setsum ~> tendsto_setsum
   953   LIMSEQ_setprod ~> tendsto_setprod
   954   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   955   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   956   LIMSEQ_imp_rabs ~> tendsto_rabs
   957   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   958   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   959   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   960   LIMSEQ_Complex ~> tendsto_Complex
   961   LIM_ident ~> tendsto_ident_at
   962   LIM_const ~> tendsto_const
   963   LIM_add ~> tendsto_add
   964   LIM_add_zero ~> tendsto_add_zero
   965   LIM_minus ~> tendsto_minus
   966   LIM_diff ~> tendsto_diff
   967   LIM_norm ~> tendsto_norm
   968   LIM_norm_zero ~> tendsto_norm_zero
   969   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   970   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   971   LIM_rabs ~> tendsto_rabs
   972   LIM_rabs_zero ~> tendsto_rabs_zero
   973   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   974   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   975   LIM_compose ~> tendsto_compose
   976   LIM_mult ~> tendsto_mult
   977   LIM_scaleR ~> tendsto_scaleR
   978   LIM_of_real ~> tendsto_of_real
   979   LIM_power ~> tendsto_power
   980   LIM_inverse ~> tendsto_inverse
   981   LIM_sgn ~> tendsto_sgn
   982   isCont_LIM_compose ~> isCont_tendsto_compose
   983   bounded_linear.LIM ~> bounded_linear.tendsto
   984   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   985   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   986   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   987   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   988   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   989   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   990 
   991 * Theory Complex_Main: The definition of infinite series was
   992 generalized.  Now it is defined on the type class {topological_space,
   993 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   994 
   995 * Theory Complex_Main: The complex exponential function "expi" is now
   996 a type-constrained abbreviation for "exp :: complex => complex"; thus
   997 several polymorphic lemmas about "exp" are now applicable to "expi".
   998 
   999 * Code generation:
  1000 
  1001   - Theory Library/Code_Char_ord provides native ordering of
  1002     characters in the target language.
  1003 
  1004   - Commands code_module and code_library are legacy, use export_code
  1005     instead.
  1006 
  1007   - Method "evaluation" is legacy, use method "eval" instead.
  1008 
  1009   - Legacy evaluator "SML" is deactivated by default.  May be
  1010     reactivated by the following theory command:
  1011 
  1012       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
  1013 
  1014 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
  1015 
  1016 * New proof method "induction" that gives induction hypotheses the
  1017 name "IH", thus distinguishing them from further hypotheses that come
  1018 from rule induction.  The latter are still called "hyps".  Method
  1019 "induction" is a thin wrapper around "induct" and follows the same
  1020 syntax.
  1021 
  1022 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
  1023 still available as a legacy feature for some time.
  1024 
  1025 * Nitpick:
  1026   - Added "need" and "total_consts" options.
  1027   - Reintroduced "show_skolems" option by popular demand.
  1028   - Renamed attribute: nitpick_def ~> nitpick_unfold.
  1029     INCOMPATIBILITY.
  1030 
  1031 * Sledgehammer:
  1032   - Use quasi-sound (and efficient) translations by default.
  1033   - Added support for the following provers: E-ToFoF, LEO-II,
  1034     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
  1035   - Automatically preplay and minimize proofs before showing them if
  1036     this can be done within reasonable time.
  1037   - sledgehammer available_provers ~> sledgehammer supported_provers.
  1038     INCOMPATIBILITY.
  1039   - Added "preplay_timeout", "slicing", "type_enc", "sound",
  1040     "max_mono_iters", and "max_new_mono_instances" options.
  1041   - Removed "explicit_apply" and "full_types" options as well as "Full
  1042     Types" Proof General menu item. INCOMPATIBILITY.
  1043 
  1044 * Metis:
  1045   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
  1046   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
  1047     INCOMPATIBILITY.
  1048 
  1049 * Command 'try':
  1050   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
  1051     "elim:" options. INCOMPATIBILITY.
  1052   - Introduced 'try' that not only runs 'try_methods' but also
  1053     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
  1054 
  1055 * Quickcheck:
  1056   - Added "eval" option to evaluate terms for the found counterexample
  1057     (currently only supported by the default (exhaustive) tester).
  1058   - Added post-processing of terms to obtain readable counterexamples
  1059     (currently only supported by the default (exhaustive) tester).
  1060   - New counterexample generator quickcheck[narrowing] enables
  1061     narrowing-based testing.  Requires the Glasgow Haskell compiler
  1062     with its installation location defined in the Isabelle settings
  1063     environment as ISABELLE_GHC.
  1064   - Removed quickcheck tester "SML" based on the SML code generator
  1065     (formly in HOL/Library).
  1066 
  1067 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
  1068 use 'partial_function' instead.
  1069 
  1070 * Theory Library/Extended_Reals replaces now the positive extended
  1071 reals found in probability theory. This file is extended by
  1072 Multivariate_Analysis/Extended_Real_Limits.
  1073 
  1074 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
  1075 from where it must be imported explicitly if it is really required.
  1076 INCOMPATIBILITY.
  1077 
  1078 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
  1079 been moved here.  INCOMPATIBILITY.
  1080 
  1081 * Theory Library/Saturated provides type of numbers with saturated
  1082 arithmetic.
  1083 
  1084 * Theory Library/Product_Lattice defines a pointwise ordering for the
  1085 product type 'a * 'b, and provides instance proofs for various order
  1086 and lattice type classes.
  1087 
  1088 * Theory Library/Countable now provides the "countable_datatype" proof
  1089 method for proving "countable" class instances for datatypes.
  1090 
  1091 * Theory Library/Cset_Monad allows do notation for computable sets
  1092 (cset) via the generic monad ad-hoc overloading facility.
  1093 
  1094 * Library: Theories of common data structures are split into theories
  1095 for implementation, an invariant-ensuring type, and connection to an
  1096 abstract type. INCOMPATIBILITY.
  1097 
  1098   - RBT is split into RBT and RBT_Mapping.
  1099   - AssocList is split and renamed into AList and AList_Mapping.
  1100   - DList is split into DList_Impl, DList, and DList_Cset.
  1101   - Cset is split into Cset and List_Cset.
  1102 
  1103 * Theory Library/Nat_Infinity has been renamed to
  1104 Library/Extended_Nat, with name changes of the following types and
  1105 constants:
  1106 
  1107   type inat   ~> type enat
  1108   Fin         ~> enat
  1109   Infty       ~> infinity (overloaded)
  1110   iSuc        ~> eSuc
  1111   the_Fin     ~> the_enat
  1112 
  1113 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
  1114 been renamed accordingly. INCOMPATIBILITY.
  1115 
  1116 * Session Multivariate_Analysis: The euclidean_space type class now
  1117 fixes a constant "Basis :: 'a set" consisting of the standard
  1118 orthonormal basis for the type. Users now have the option of
  1119 quantifying over this set instead of using the "basis" function, e.g.
  1120 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
  1121 
  1122 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
  1123 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
  1124 "Cart_nth" and "Cart_lambda" have been respectively renamed to
  1125 "vec_nth" and "vec_lambda"; theorems mentioning those names have
  1126 changed to match. Definition theorems for overloaded constants now use
  1127 the standard "foo_vec_def" naming scheme. A few other theorems have
  1128 been renamed as follows (INCOMPATIBILITY):
  1129 
  1130   Cart_eq          ~> vec_eq_iff
  1131   dist_nth_le_cart ~> dist_vec_nth_le
  1132   tendsto_vector   ~> vec_tendstoI
  1133   Cauchy_vector    ~> vec_CauchyI
  1134 
  1135 * Session Multivariate_Analysis: Several duplicate theorems have been
  1136 removed, and other theorems have been renamed or replaced with more
  1137 general versions. INCOMPATIBILITY.
  1138 
  1139   finite_choice ~> finite_set_choice
  1140   eventually_conjI ~> eventually_conj
  1141   eventually_and ~> eventually_conj_iff
  1142   eventually_false ~> eventually_False
  1143   setsum_norm ~> norm_setsum
  1144   Lim_sequentially ~> LIMSEQ_def
  1145   Lim_ident_at ~> LIM_ident
  1146   Lim_const ~> tendsto_const
  1147   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
  1148   Lim_neg ~> tendsto_minus
  1149   Lim_add ~> tendsto_add
  1150   Lim_sub ~> tendsto_diff
  1151   Lim_mul ~> tendsto_scaleR
  1152   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
  1153   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
  1154   Lim_linear ~> bounded_linear.tendsto
  1155   Lim_component ~> tendsto_euclidean_component
  1156   Lim_component_cart ~> tendsto_vec_nth
  1157   Lim_inner ~> tendsto_inner [OF tendsto_const]
  1158   dot_lsum ~> inner_setsum_left
  1159   dot_rsum ~> inner_setsum_right
  1160   continuous_cmul ~> continuous_scaleR [OF continuous_const]
  1161   continuous_neg ~> continuous_minus
  1162   continuous_sub ~> continuous_diff
  1163   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
  1164   continuous_mul ~> continuous_scaleR
  1165   continuous_inv ~> continuous_inverse
  1166   continuous_at_within_inv ~> continuous_at_within_inverse
  1167   continuous_at_inv ~> continuous_at_inverse
  1168   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
  1169   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
  1170   continuous_at_component ~> continuous_component [OF continuous_at_id]
  1171   continuous_on_neg ~> continuous_on_minus
  1172   continuous_on_sub ~> continuous_on_diff
  1173   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
  1174   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
  1175   continuous_on_mul ~> continuous_on_scaleR
  1176   continuous_on_mul_real ~> continuous_on_mult
  1177   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
  1178   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
  1179   continuous_on_inverse ~> continuous_on_inv
  1180   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
  1181   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
  1182   subset_interior ~> interior_mono
  1183   subset_closure ~> closure_mono
  1184   closure_univ ~> closure_UNIV
  1185   real_arch_lt ~> reals_Archimedean2
  1186   real_arch ~> reals_Archimedean3
  1187   real_abs_norm ~> abs_norm_cancel
  1188   real_abs_sub_norm ~> norm_triangle_ineq3
  1189   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
  1190 
  1191 * Session HOL-Probability:
  1192   - Caratheodory's extension lemma is now proved for ring_of_sets.
  1193   - Infinite products of probability measures are now available.
  1194   - Sigma closure is independent, if the generator is independent
  1195   - Use extended reals instead of positive extended
  1196     reals. INCOMPATIBILITY.
  1197 
  1198 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
  1199 
  1200   expand_fun_below ~> fun_below_iff
  1201   below_fun_ext ~> fun_belowI
  1202   expand_cfun_eq ~> cfun_eq_iff
  1203   ext_cfun ~> cfun_eqI
  1204   expand_cfun_below ~> cfun_below_iff
  1205   below_cfun_ext ~> cfun_belowI
  1206   monofun_fun_fun ~> fun_belowD
  1207   monofun_fun_arg ~> monofunE
  1208   monofun_lub_fun ~> adm_monofun [THEN admD]
  1209   cont_lub_fun ~> adm_cont [THEN admD]
  1210   cont2cont_Rep_CFun ~> cont2cont_APP
  1211   cont_Rep_CFun_app ~> cont_APP_app
  1212   cont_Rep_CFun_app_app ~> cont_APP_app_app
  1213   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
  1214   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
  1215   contlub_cfun ~> lub_APP [symmetric]
  1216   contlub_LAM ~> lub_LAM [symmetric]
  1217   thelubI ~> lub_eqI
  1218   UU_I ~> bottomI
  1219   lift_distinct1 ~> lift.distinct(1)
  1220   lift_distinct2 ~> lift.distinct(2)
  1221   Def_not_UU ~> lift.distinct(2)
  1222   Def_inject ~> lift.inject
  1223   below_UU_iff ~> below_bottom_iff
  1224   eq_UU_iff ~> eq_bottom_iff
  1225 
  1226 
  1227 *** Document preparation ***
  1228 
  1229 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
  1230 isar-ref manual, both for description and actual application of the
  1231 same.
  1232 
  1233 * Antiquotation @{value} evaluates the given term and presents its
  1234 result.
  1235 
  1236 * Antiquotations: term style "isub" provides ad-hoc conversion of
  1237 variables x1, y23 into subscripted form x\<^isub>1,
  1238 y\<^isub>2\<^isub>3.
  1239 
  1240 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
  1241 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
  1242 
  1243 * Localized \isabellestyle switch can be used within blocks or groups
  1244 like this:
  1245 
  1246   \isabellestyle{it}  %preferred default
  1247   {\isabellestylett @{text "typewriter stuff"}}
  1248 
  1249 * Discontinued special treatment of hard tabulators.  Implicit
  1250 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
  1251 layouts.
  1252 
  1253 
  1254 *** ML ***
  1255 
  1256 * The inner syntax of sort/type/term/prop supports inlined YXML
  1257 representations within quoted string tokens.  By encoding logical
  1258 entities via Term_XML (in ML or Scala) concrete syntax can be
  1259 bypassed, which is particularly useful for producing bits of text
  1260 under external program control.
  1261 
  1262 * Antiquotations for ML and document preparation are managed as theory
  1263 data, which requires explicit setup.
  1264 
  1265 * Isabelle_Process.is_active allows tools to check if the official
  1266 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
  1267 (better known as Proof General).
  1268 
  1269 * Structure Proof_Context follows standard naming scheme.  Old
  1270 ProofContext is still available for some time as legacy alias.
  1271 
  1272 * Structure Timing provides various operations for timing; supersedes
  1273 former start_timing/end_timing etc.
  1274 
  1275 * Path.print is the official way to show file-system paths to users
  1276 (including quotes etc.).
  1277 
  1278 * Inner syntax: identifiers in parse trees of generic categories
  1279 "logic", "aprop", "idt" etc. carry position information (disguised as
  1280 type constraints).  Occasional INCOMPATIBILITY with non-compliant
  1281 translations that choke on unexpected type constraints.  Positions can
  1282 be stripped in ML translations via Syntax.strip_positions /
  1283 Syntax.strip_positions_ast, or via the syntax constant
  1284 "_strip_positions" within parse trees.  As last resort, positions can
  1285 be disabled via the configuration option Syntax.positions, which is
  1286 called "syntax_positions" in Isar attribute syntax.
  1287 
  1288 * Discontinued special status of various ML structures that contribute
  1289 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
  1290 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
  1291 refer directly to Ast.Constant, Lexicon.is_identifier,
  1292 Syntax_Trans.mk_binder_tr etc.
  1293 
  1294 * Typed print translation: discontinued show_sorts argument, which is
  1295 already available via context of "advanced" translation.
  1296 
  1297 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
  1298 goal states; body tactic needs to address all subgoals uniformly.
  1299 
  1300 * Slightly more special eq_list/eq_set, with shortcut involving
  1301 pointer equality (assumes that eq relation is reflexive).
  1302 
  1303 * Classical tactics use proper Proof.context instead of historic types
  1304 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  1305 operate directly on Proof.context.  Raw type claset retains its use as
  1306 snapshot of the classical context, which can be recovered via
  1307 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  1308 INCOMPATIBILITY, classical tactics and derived proof methods require
  1309 proper Proof.context.
  1310 
  1311 
  1312 *** System ***
  1313 
  1314 * Discontinued support for Poly/ML 5.2, which was the last version
  1315 without proper multithreading and TimeLimit implementation.
  1316 
  1317 * Discontinued old lib/scripts/polyml-platform, which has been
  1318 obsolete since Isabelle2009-2.
  1319 
  1320 * Various optional external tools are referenced more robustly and
  1321 uniformly by explicit Isabelle settings as follows:
  1322 
  1323   ISABELLE_CSDP   (formerly CSDP_EXE)
  1324   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  1325   ISABELLE_OCAML  (formerly EXEC_OCAML)
  1326   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  1327   ISABELLE_YAP    (formerly EXEC_YAP)
  1328 
  1329 Note that automated detection from the file-system or search path has
  1330 been discontinued.  INCOMPATIBILITY.
  1331 
  1332 * Scala layer provides JVM method invocation service for static
  1333 methods of type (String)String, see Invoke_Scala.method in ML.  For
  1334 example:
  1335 
  1336   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  1337 
  1338 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  1339 this allows to pass structured values between ML and Scala.
  1340 
  1341 * The IsabelleText fonts includes some further glyphs to support the
  1342 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  1343 installed a local copy (which is normally *not* required) need to
  1344 delete or update it from ~~/lib/fonts/.
  1345 
  1346 
  1347 
  1348 New in Isabelle2011 (January 2011)
  1349 ----------------------------------
  1350 
  1351 *** General ***
  1352 
  1353 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  1354 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  1355 useful tooltips and hyperlinks produced from its static analysis.  The
  1356 bundled component provides an executable Isabelle tool that can be run
  1357 like this:
  1358 
  1359   Isabelle2011/bin/isabelle jedit
  1360 
  1361 * Significantly improved Isabelle/Isar implementation manual.
  1362 
  1363 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  1364 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  1365 while the default heap location within that directory lacks that extra
  1366 suffix.  This isolates multiple Isabelle installations from each
  1367 other, avoiding problems with old settings in new versions.
  1368 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  1369 
  1370 * Source files are always encoded as UTF-8, instead of old-fashioned
  1371 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  1372 the following package declarations:
  1373 
  1374   \usepackage[utf8]{inputenc}
  1375   \usepackage{textcomp}
  1376 
  1377 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  1378 a Unicode character is treated as a single symbol, not a sequence of
  1379 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  1380 contain symbols without further backslash escapes, Unicode can now be
  1381 used here as well.  Recall that Symbol.explode in ML provides a
  1382 consistent view on symbols, while raw explode (or String.explode)
  1383 merely give a byte-oriented representation.
  1384 
  1385 * Theory loader: source files are primarily located via the master
  1386 directory of each theory node (where the .thy file itself resides).
  1387 The global load path is still partially available as legacy feature.
  1388 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  1389 explicit paths, relatively to the theory.
  1390 
  1391 * Special treatment of ML file names has been discontinued.
  1392 Historically, optional extensions .ML or .sml were added on demand --
  1393 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  1394 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  1395 
  1396 * Various options that affect pretty printing etc. are now properly
  1397 handled within the context via configuration options, instead of
  1398 unsynchronized references or print modes.  There are both ML Config.T
  1399 entities and Isar declaration attributes to access these.
  1400 
  1401   ML (Config.T)                 Isar (attribute)
  1402 
  1403   eta_contract                  eta_contract
  1404   show_brackets                 show_brackets
  1405   show_sorts                    show_sorts
  1406   show_types                    show_types
  1407   show_question_marks           show_question_marks
  1408   show_consts                   show_consts
  1409   show_abbrevs                  show_abbrevs
  1410 
  1411   Syntax.ast_trace              syntax_ast_trace
  1412   Syntax.ast_stat               syntax_ast_stat
  1413   Syntax.ambiguity_level        syntax_ambiguity_level
  1414 
  1415   Goal_Display.goals_limit      goals_limit
  1416   Goal_Display.show_main_goal   show_main_goal
  1417 
  1418   Method.rule_trace             rule_trace
  1419 
  1420   Thy_Output.display            thy_output_display
  1421   Thy_Output.quotes             thy_output_quotes
  1422   Thy_Output.indent             thy_output_indent
  1423   Thy_Output.source             thy_output_source
  1424   Thy_Output.break              thy_output_break
  1425 
  1426 Note that corresponding "..._default" references in ML may only be
  1427 changed globally at the ROOT session setup, but *not* within a theory.
  1428 The option "show_abbrevs" supersedes the former print mode
  1429 "no_abbrevs" with inverted meaning.
  1430 
  1431 * More systematic naming of some configuration options.
  1432 INCOMPATIBILITY.
  1433 
  1434   trace_simp  ~>  simp_trace
  1435   debug_simp  ~>  simp_debug
  1436 
  1437 * Support for real valued configuration options, using simplistic
  1438 floating-point notation that coincides with the inner syntax for
  1439 float_token.
  1440 
  1441 * Support for real valued preferences (with approximative PGIP type):
  1442 front-ends need to accept "pgint" values in float notation.
  1443 INCOMPATIBILITY.
  1444 
  1445 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  1446 DejaVu Sans.
  1447 
  1448 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  1449 
  1450 
  1451 *** Pure ***
  1452 
  1453 * Command 'type_synonym' (with single argument) replaces somewhat
  1454 outdated 'types', which is still available as legacy feature for some
  1455 time.
  1456 
  1457 * Command 'nonterminal' (with 'and' separated list of arguments)
  1458 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  1459 
  1460 * Command 'notepad' replaces former 'example_proof' for
  1461 experimentation in Isar without any result.  INCOMPATIBILITY.
  1462 
  1463 * Locale interpretation commands 'interpret' and 'sublocale' accept
  1464 lists of equations to map definitions in a locale to appropriate
  1465 entities in the context of the interpretation.  The 'interpretation'
  1466 command already provided this functionality.
  1467 
  1468 * Diagnostic command 'print_dependencies' prints the locale instances
  1469 that would be activated if the specified expression was interpreted in
  1470 the current context.  Variant "print_dependencies!" assumes a context
  1471 without interpretations.
  1472 
  1473 * Diagnostic command 'print_interps' prints interpretations in proofs
  1474 in addition to interpretations in theories.
  1475 
  1476 * Discontinued obsolete 'global' and 'local' commands to manipulate
  1477 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  1478 Sign.root_path and Sign.local_path may be applied directly where this
  1479 feature is still required for historical reasons.
  1480 
  1481 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  1482 'definition' instead.
  1483 
  1484 * The "prems" fact, which refers to the accidental collection of
  1485 foundational premises in the context, is now explicitly marked as
  1486 legacy feature and will be discontinued soon.  Consider using "assms"
  1487 of the head statement or reference facts by explicit names.
  1488 
  1489 * Document antiquotations @{class} and @{type} print classes and type
  1490 constructors.
  1491 
  1492 * Document antiquotation @{file} checks file/directory entries within
  1493 the local file system.
  1494 
  1495 
  1496 *** HOL ***
  1497 
  1498 * Coercive subtyping: functions can be declared as coercions and type
  1499 inference will add them as necessary upon input of a term.  Theory
  1500 Complex_Main declares real :: nat => real and real :: int => real as
  1501 coercions. A coercion function f is declared like this:
  1502 
  1503   declare [[coercion f]]
  1504 
  1505 To lift coercions through type constructors (e.g. from nat => real to
  1506 nat list => real list), map functions can be declared, e.g.
  1507 
  1508   declare [[coercion_map map]]
  1509 
  1510 Currently coercion inference is activated only in theories including
  1511 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1512 the configuration option "coercion_enabled", e.g. it can be enabled in
  1513 other theories like this:
  1514 
  1515   declare [[coercion_enabled]]
  1516 
  1517 * Command 'partial_function' provides basic support for recursive
  1518 function definitions over complete partial orders.  Concrete instances
  1519 are provided for i) the option type, ii) tail recursion on arbitrary
  1520 types, and iii) the heap monad of Imperative_HOL.  See
  1521 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1522 for examples.
  1523 
  1524 * Function package: f.psimps rules are no longer implicitly declared
  1525 as [simp].  INCOMPATIBILITY.
  1526 
  1527 * Datatype package: theorems generated for executable equality (class
  1528 "eq") carry proper names and are treated as default code equations.
  1529 
  1530 * Inductive package: now offers command 'inductive_simps' to
  1531 automatically derive instantiated and simplified equations for
  1532 inductive predicates, similar to 'inductive_cases'.
  1533 
  1534 * Command 'enriched_type' allows to register properties of the
  1535 functorial structure of types.
  1536 
  1537 * Improved infrastructure for term evaluation using code generator
  1538 techniques, in particular static evaluation conversions.
  1539 
  1540 * Code generator: Scala (2.8 or higher) has been added to the target
  1541 languages.
  1542 
  1543 * Code generator: globbing constant expressions "*" and "Theory.*"
  1544 have been replaced by the more idiomatic "_" and "Theory._".
  1545 INCOMPATIBILITY.
  1546 
  1547 * Code generator: export_code without explicit file declaration prints
  1548 to standard output.  INCOMPATIBILITY.
  1549 
  1550 * Code generator: do not print function definitions for case
  1551 combinators any longer.
  1552 
  1553 * Code generator: simplification with rules determined with
  1554 src/Tools/Code/code_simp.ML and method "code_simp".
  1555 
  1556 * Code generator for records: more idiomatic representation of record
  1557 types.  Warning: records are not covered by ancient SML code
  1558 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1559 rep_datatype declaration helps to succeed then:
  1560 
  1561   record 'a foo = ...
  1562   ...
  1563   rep_datatype foo_ext ...
  1564 
  1565 * Records: logical foundation type for records does not carry a
  1566 '_type' suffix any longer (obsolete due to authentic syntax).
  1567 INCOMPATIBILITY.
  1568 
  1569 * Quickcheck now by default uses exhaustive testing instead of random
  1570 testing.  Random testing can be invoked by "quickcheck [random]",
  1571 exhaustive testing by "quickcheck [exhaustive]".
  1572 
  1573 * Quickcheck instantiates polymorphic types with small finite
  1574 datatypes by default. This enables a simple execution mechanism to
  1575 handle quantifiers and function equality over the finite datatypes.
  1576 
  1577 * Quickcheck random generator has been renamed from "code" to
  1578 "random".  INCOMPATIBILITY.
  1579 
  1580 * Quickcheck now has a configurable time limit which is set to 30
  1581 seconds by default. This can be changed by adding [timeout = n] to the
  1582 quickcheck command. The time limit for Auto Quickcheck is still set
  1583 independently.
  1584 
  1585 * Quickcheck in locales considers interpretations of that locale for
  1586 counter example search.
  1587 
  1588 * Sledgehammer:
  1589   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1590     method. See the Sledgehammer manual for details ("isabelle doc
  1591     sledgehammer").
  1592   - Renamed commands:
  1593     sledgehammer atp_info ~> sledgehammer running_provers
  1594     sledgehammer atp_kill ~> sledgehammer kill_provers
  1595     sledgehammer available_atps ~> sledgehammer available_provers
  1596     INCOMPATIBILITY.
  1597   - Renamed options:
  1598     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1599     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1600     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1601     (and "ms" and "min" are no longer supported)
  1602     INCOMPATIBILITY.
  1603 
  1604 * Nitpick:
  1605   - Renamed options:
  1606     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1607     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1608     INCOMPATIBILITY.
  1609   - Added support for partial quotient types.
  1610   - Added local versions of the "Nitpick.register_xxx" functions.
  1611   - Added "whack" option.
  1612   - Allow registration of quotient types as codatatypes.
  1613   - Improved "merge_type_vars" option to merge more types.
  1614   - Removed unsound "fast_descrs" option.
  1615   - Added custom symmetry breaking for datatypes, making it possible to reach
  1616     higher cardinalities.
  1617   - Prevent the expansion of too large definitions.
  1618 
  1619 * Proof methods "metis" and "meson" now have configuration options
  1620 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1621 to diagnose these tools. E.g.
  1622 
  1623     using [[metis_trace = true]]
  1624 
  1625 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1626 manually as command 'solve_direct'.
  1627 
  1628 * The default SMT solver Z3 must be enabled explicitly (due to
  1629 licensing issues) by setting the environment variable
  1630 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1631 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1632 changing the SMT solver is done via the configuration option
  1633 "smt_solver".
  1634 
  1635 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1636 i.e. "remote_cvc3" and "remote_z3".
  1637 
  1638 * Added basic SMT support for datatypes, records, and typedefs using
  1639 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1640 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1641 support for a similar behavior).  Minor INCOMPATIBILITY.
  1642 
  1643 * Changed SMT configuration options:
  1644   - Renamed:
  1645     z3_proofs ~> smt_oracle (with inverted meaning)
  1646     z3_trace_assms ~> smt_trace_used_facts
  1647     INCOMPATIBILITY.
  1648   - Added:
  1649     smt_verbose
  1650     smt_random_seed
  1651     smt_datatypes
  1652     smt_infer_triggers
  1653     smt_monomorph_limit
  1654     cvc3_options
  1655     remote_cvc3_options
  1656     remote_z3_options
  1657     yices_options
  1658 
  1659 * Boogie output files (.b2i files) need to be declared in the theory
  1660 header.
  1661 
  1662 * Simplification procedure "list_to_set_comprehension" rewrites list
  1663 comprehensions applied to List.set to set comprehensions.  Occasional
  1664 INCOMPATIBILITY, may be deactivated like this:
  1665 
  1666   declare [[simproc del: list_to_set_comprehension]]
  1667 
  1668 * Removed old version of primrec package.  INCOMPATIBILITY.
  1669 
  1670 * Removed simplifier congruence rule of "prod_case", as has for long
  1671 been the case with "split".  INCOMPATIBILITY.
  1672 
  1673 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1674 
  1675 * Removed [split_format ... and ... and ...] version of
  1676 [split_format].  Potential INCOMPATIBILITY.
  1677 
  1678 * Predicate "sorted" now defined inductively, with nice induction
  1679 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1680 
  1681 * Constant "contents" renamed to "the_elem", to free the generic name
  1682 contents for other uses.  INCOMPATIBILITY.
  1683 
  1684 * Renamed class eq and constant eq (for code generation) to class
  1685 equal and constant equal, plus renaming of related facts and various
  1686 tuning.  INCOMPATIBILITY.
  1687 
  1688 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1689 
  1690 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1691 INCOMPATIBILITY.
  1692 
  1693 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1694 avoid confusion with finite sets.  INCOMPATIBILITY.
  1695 
  1696 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1697 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1698 for congruent(2)).
  1699 
  1700 * Some previously unqualified names have been qualified:
  1701 
  1702   types
  1703     bool ~> HOL.bool
  1704     nat ~> Nat.nat
  1705 
  1706   constants
  1707     Trueprop ~> HOL.Trueprop
  1708     True ~> HOL.True
  1709     False ~> HOL.False
  1710     op & ~> HOL.conj
  1711     op | ~> HOL.disj
  1712     op --> ~> HOL.implies
  1713     op = ~> HOL.eq
  1714     Not ~> HOL.Not
  1715     The ~> HOL.The
  1716     All ~> HOL.All
  1717     Ex ~> HOL.Ex
  1718     Ex1 ~> HOL.Ex1
  1719     Let ~> HOL.Let
  1720     If ~> HOL.If
  1721     Ball ~> Set.Ball
  1722     Bex ~> Set.Bex
  1723     Suc ~> Nat.Suc
  1724     Pair ~> Product_Type.Pair
  1725     fst ~> Product_Type.fst
  1726     snd ~> Product_Type.snd
  1727     curry ~> Product_Type.curry
  1728     op : ~> Set.member
  1729     Collect ~> Set.Collect
  1730 
  1731 INCOMPATIBILITY.
  1732 
  1733 * More canonical naming convention for some fundamental definitions:
  1734 
  1735     bot_bool_eq ~> bot_bool_def
  1736     top_bool_eq ~> top_bool_def
  1737     inf_bool_eq ~> inf_bool_def
  1738     sup_bool_eq ~> sup_bool_def
  1739     bot_fun_eq  ~> bot_fun_def
  1740     top_fun_eq  ~> top_fun_def
  1741     inf_fun_eq  ~> inf_fun_def
  1742     sup_fun_eq  ~> sup_fun_def
  1743 
  1744 INCOMPATIBILITY.
  1745 
  1746 * More stylized fact names:
  1747 
  1748   expand_fun_eq ~> fun_eq_iff
  1749   expand_set_eq ~> set_eq_iff
  1750   set_ext       ~> set_eqI
  1751   nat_number    ~> eval_nat_numeral
  1752 
  1753 INCOMPATIBILITY.
  1754 
  1755 * Refactoring of code-generation specific operations in theory List:
  1756 
  1757   constants
  1758     null ~> List.null
  1759 
  1760   facts
  1761     mem_iff ~> member_def
  1762     null_empty ~> null_def
  1763 
  1764 INCOMPATIBILITY.  Note that these were not supposed to be used
  1765 regularly unless for striking reasons; their main purpose was code
  1766 generation.
  1767 
  1768 Various operations from the Haskell prelude are used for generating
  1769 Haskell code.
  1770 
  1771 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1772 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1773 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1774 
  1775 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1776 "*" and "+" respectively.  INCOMPATIBILITY.
  1777 
  1778 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1779 "Sum_Type.Plus" instead.
  1780 
  1781 * Constant "split" has been merged with constant "prod_case"; names of
  1782 ML functions, facts etc. involving split have been retained so far,
  1783 though.  INCOMPATIBILITY.
  1784 
  1785 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1786 instead.  INCOMPATIBILITY.
  1787 
  1788 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1789 INCOMPATIBILITY.
  1790 
  1791 * Former theory Library/Enum is now part of the HOL-Main image.
  1792 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1793 referred to by its qualified name.
  1794 
  1795   enum    ~>  Enum.enum
  1796   nlists  ~>  Enum.nlists
  1797   product ~>  Enum.product
  1798 
  1799 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1800 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1801 INCOMPATIBILITY.
  1802 
  1803 * Theory Library/SetsAndFunctions has been split into
  1804 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1805 for instance definitions for functions; various improvements.
  1806 INCOMPATIBILITY.
  1807 
  1808 * Theory Library/Multiset provides stable quicksort implementation of
  1809 sort_key.
  1810 
  1811 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1812 INCOMPATIBILITY.
  1813 
  1814 * Session Multivariate_Analysis: introduced a type class for euclidean
  1815 space.  Most theorems are now stated in terms of euclidean spaces
  1816 instead of finite cartesian products.
  1817 
  1818   types
  1819     real ^ 'n ~>  'a::real_vector
  1820               ~>  'a::euclidean_space
  1821               ~>  'a::ordered_euclidean_space
  1822         (depends on your needs)
  1823 
  1824   constants
  1825      _ $ _        ~> _ $$ _
  1826      \<chi> x. _  ~> \<chi>\<chi> x. _
  1827      CARD('n)     ~> DIM('a)
  1828 
  1829 Also note that the indices are now natural numbers and not from some
  1830 finite type. Finite cartesian products of euclidean spaces, products
  1831 of euclidean spaces the real and complex numbers are instantiated to
  1832 be euclidean_spaces.  INCOMPATIBILITY.
  1833 
  1834 * Session Probability: introduced pextreal as positive extended real
  1835 numbers.  Use pextreal as value for measures.  Introduce the
  1836 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1837 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1838 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1839 
  1840 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1841 INCOMPATIBILITY.
  1842 
  1843 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1844 prove verification conditions generated by the SPARK Ada program
  1845 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1846 
  1847 
  1848 *** HOL-Algebra ***
  1849 
  1850 * Theorems for additive ring operations (locale abelian_monoid and
  1851 descendants) are generated by interpretation from their multiplicative
  1852 counterparts.  Names (in particular theorem names) have the mandatory
  1853 qualifier 'add'.  Previous theorem names are redeclared for
  1854 compatibility.
  1855 
  1856 * Structure "int_ring" is now an abbreviation (previously a
  1857 definition).  This fits more natural with advanced interpretations.
  1858 
  1859 
  1860 *** HOLCF ***
  1861 
  1862 * The domain package now runs in definitional mode by default: The
  1863 former command 'new_domain' is now called 'domain'.  To use the domain
  1864 package in its original axiomatic mode, use 'domain (unsafe)'.
  1865 INCOMPATIBILITY.
  1866 
  1867 * The new class "domain" is now the default sort.  Class "predomain"
  1868 is an unpointed version of "domain". Theories can be updated by
  1869 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1870 
  1871   'a::type ~> 'a::countable
  1872   'a::cpo  ~> 'a::predomain
  1873   'a::pcpo ~> 'a::domain
  1874 
  1875 * The old type class "rep" has been superseded by class "domain".
  1876 Accordingly, users of the definitional package must remove any
  1877 "default_sort rep" declarations.  INCOMPATIBILITY.
  1878 
  1879 * The domain package (definitional mode) now supports unpointed
  1880 predomain argument types, as long as they are marked 'lazy'. (Strict
  1881 arguments must be in class "domain".) For example, the following
  1882 domain definition now works:
  1883 
  1884   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1885 
  1886 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1887 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1888 'a option, and 'a list.  Additionally, it configures fixrec and the
  1889 domain package to work with these types.  For example:
  1890 
  1891   fixrec isInl :: "('a + 'b) u -> tr"
  1892     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1893 
  1894   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1895 
  1896 * The "(permissive)" option of fixrec has been replaced with a
  1897 per-equation "(unchecked)" option. See
  1898 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1899 
  1900 * The "bifinite" class no longer fixes a constant "approx"; the class
  1901 now just asserts that such a function exists.  INCOMPATIBILITY.
  1902 
  1903 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1904 defines an embedding of type 'a defl into udom by default; instances
  1905 of "bifinite" and "domain" classes are available in
  1906 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1907 
  1908 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1909 
  1910 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1911 
  1912 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1913 
  1914 * The function "cprod_map" has been renamed to "prod_map".
  1915 INCOMPATIBILITY.
  1916 
  1917 * The monadic bind operator on each powerdomain has new binder syntax
  1918 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1919 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1920 
  1921 * The infix syntax for binary union on each powerdomain has changed
  1922 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1923 syntax.  INCOMPATIBILITY.
  1924 
  1925 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1926 still supported as an input translation.
  1927 
  1928 * Renamed some theorems (the original names are also still available).
  1929 
  1930   expand_fun_below   ~> fun_below_iff
  1931   below_fun_ext      ~> fun_belowI
  1932   expand_cfun_eq     ~> cfun_eq_iff
  1933   ext_cfun           ~> cfun_eqI
  1934   expand_cfun_below  ~> cfun_below_iff
  1935   below_cfun_ext     ~> cfun_belowI
  1936   cont2cont_Rep_CFun ~> cont2cont_APP
  1937 
  1938 * The Abs and Rep functions for various types have changed names.
  1939 Related theorem names have also changed to match. INCOMPATIBILITY.
  1940 
  1941   Rep_CFun  ~> Rep_cfun
  1942   Abs_CFun  ~> Abs_cfun
  1943   Rep_Sprod ~> Rep_sprod
  1944   Abs_Sprod ~> Abs_sprod
  1945   Rep_Ssum  ~> Rep_ssum
  1946   Abs_Ssum  ~> Abs_ssum
  1947 
  1948 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1949 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1950 
  1951 * Various changes to bisimulation/coinduction with domain package:
  1952 
  1953   - Definitions of "bisim" constants no longer mention definedness.
  1954   - With mutual recursion, "bisim" predicate is now curried.
  1955   - With mutual recursion, each type gets a separate coind theorem.
  1956   - Variable names in bisim_def and coinduct rules have changed.
  1957 
  1958 INCOMPATIBILITY.
  1959 
  1960 * Case combinators generated by the domain package for type "foo" are
  1961 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1962 
  1963 * Several theorems have been renamed to more accurately reflect the
  1964 names of constants and types involved.  INCOMPATIBILITY.
  1965 
  1966   thelub_const    ~> lub_const
  1967   lub_const       ~> is_lub_const
  1968   thelubI         ~> lub_eqI
  1969   is_lub_lub      ~> is_lubD2
  1970   lubI            ~> is_lub_lub
  1971   unique_lub      ~> is_lub_unique
  1972   is_ub_lub       ~> is_lub_rangeD1
  1973   lub_bin_chain   ~> is_lub_bin_chain
  1974   lub_fun         ~> is_lub_fun
  1975   thelub_fun      ~> lub_fun
  1976   thelub_cfun     ~> lub_cfun
  1977   thelub_Pair     ~> lub_Pair
  1978   lub_cprod       ~> is_lub_prod
  1979   thelub_cprod    ~> lub_prod
  1980   minimal_cprod   ~> minimal_prod
  1981   inst_cprod_pcpo ~> inst_prod_pcpo
  1982   UU_I            ~> bottomI
  1983   compact_UU      ~> compact_bottom
  1984   deflation_UU    ~> deflation_bottom
  1985   finite_deflation_UU ~> finite_deflation_bottom
  1986 
  1987 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1988 
  1989   sq_ord_less_eq_trans ~> below_eq_trans
  1990   sq_ord_eq_less_trans ~> eq_below_trans
  1991   refl_less            ~> below_refl
  1992   trans_less           ~> below_trans
  1993   antisym_less         ~> below_antisym
  1994   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1995   box_less             ~> box_below
  1996   rev_trans_less       ~> rev_below_trans
  1997   not_less2not_eq      ~> not_below2not_eq
  1998   less_UU_iff          ~> below_UU_iff
  1999   flat_less_iff        ~> flat_below_iff
  2000   adm_less             ~> adm_below
  2001   adm_not_less         ~> adm_not_below
  2002   adm_compact_not_less ~> adm_compact_not_below
  2003   less_fun_def         ~> below_fun_def
  2004   expand_fun_less      ~> fun_below_iff
  2005   less_fun_ext         ~> fun_belowI
  2006   less_discr_def       ~> below_discr_def
  2007   discr_less_eq        ~> discr_below_eq
  2008   less_unit_def        ~> below_unit_def
  2009   less_cprod_def       ~> below_prod_def
  2010   prod_lessI           ~> prod_belowI
  2011   Pair_less_iff        ~> Pair_below_iff
  2012   fst_less_iff         ~> fst_below_iff
  2013   snd_less_iff         ~> snd_below_iff
  2014   expand_cfun_less     ~> cfun_below_iff
  2015   less_cfun_ext        ~> cfun_belowI
  2016   injection_less       ~> injection_below
  2017   less_up_def          ~> below_up_def
  2018   not_Iup_less         ~> not_Iup_below
  2019   Iup_less             ~> Iup_below
  2020   up_less              ~> up_below
  2021   Def_inject_less_eq   ~> Def_below_Def
  2022   Def_less_is_eq       ~> Def_below_iff
  2023   spair_less_iff       ~> spair_below_iff
  2024   less_sprod           ~> below_sprod
  2025   spair_less           ~> spair_below
  2026   sfst_less_iff        ~> sfst_below_iff
  2027   ssnd_less_iff        ~> ssnd_below_iff
  2028   fix_least_less       ~> fix_least_below
  2029   dist_less_one        ~> dist_below_one
  2030   less_ONE             ~> below_ONE
  2031   ONE_less_iff         ~> ONE_below_iff
  2032   less_sinlD           ~> below_sinlD
  2033   less_sinrD           ~> below_sinrD
  2034 
  2035 
  2036 *** FOL and ZF ***
  2037 
  2038 * All constant names are now qualified internally and use proper
  2039 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  2040 
  2041 
  2042 *** ML ***
  2043 
  2044 * Antiquotation @{assert} inlines a function bool -> unit that raises
  2045 Fail if the argument is false.  Due to inlining the source position of
  2046 failed assertions is included in the error output.
  2047 
  2048 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  2049 text is in practice always evaluated with a stable theory checkpoint.
  2050 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  2051 
  2052 * Antiquotation @{theory A} refers to theory A from the ancestry of
  2053 the current context, not any accidental theory loader state as before.
  2054 Potential INCOMPATIBILITY, subtle change in semantics.
  2055 
  2056 * Syntax.pretty_priority (default 0) configures the required priority
  2057 of pretty-printed output and thus affects insertion of parentheses.
  2058 
  2059 * Syntax.default_root (default "any") configures the inner syntax
  2060 category (nonterminal symbol) for parsing of terms.
  2061 
  2062 * Former exception Library.UnequalLengths now coincides with
  2063 ListPair.UnequalLengths.
  2064 
  2065 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  2066 main functionality is provided by structure Simplifier.
  2067 
  2068 * Renamed raw "explode" function to "raw_explode" to emphasize its
  2069 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  2070 almost all situations.
  2071 
  2072 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  2073 See implementation manual for further details on exceptions in
  2074 Isabelle/ML.
  2075 
  2076 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  2077 meaning.
  2078 
  2079 * Renamed structure PureThy to Pure_Thy and moved most of its
  2080 operations to structure Global_Theory, to emphasize that this is
  2081 rarely-used global-only stuff.
  2082 
  2083 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  2084 instead (or tracing for high-volume output).
  2085 
  2086 * Configuration option show_question_marks only affects regular pretty
  2087 printing of types and terms, not raw Term.string_of_vname.
  2088 
  2089 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  2090 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  2091 @{thms} for most purposes.
  2092 
  2093 * ML structure Unsynchronized is never opened, not even in Isar
  2094 interaction mode as before.  Old Unsynchronized.set etc. have been
  2095 discontinued -- use plain := instead.  This should be *rare* anyway,
  2096 since modern tools always work via official context data, notably
  2097 configuration options.
  2098 
  2099 * Parallel and asynchronous execution requires special care concerning
  2100 interrupts.  Structure Exn provides some convenience functions that
  2101 avoid working directly with raw Interrupt.  User code must not absorb
  2102 interrupts -- intermediate handling (for cleanup etc.) needs to be
  2103 followed by re-raising of the original exception.  Another common
  2104 source of mistakes are "handle _" patterns, which make the meaning of
  2105 the program subject to physical effects of the environment.
  2106 
  2107 
  2108 
  2109 New in Isabelle2009-2 (June 2010)
  2110 ---------------------------------
  2111 
  2112 *** General ***
  2113 
  2114 * Authentic syntax for *all* logical entities (type classes, type
  2115 constructors, term constants): provides simple and robust
  2116 correspondence between formal entities and concrete syntax.  Within
  2117 the parse tree / AST representations, "constants" are decorated by
  2118 their category (class, type, const) and spelled out explicitly with
  2119 their full internal name.
  2120 
  2121 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  2122 and translations (translation rules and translation functions in ML).
  2123 Some hints on upgrading:
  2124 
  2125   - Many existing uses of 'syntax' and 'translations' can be replaced
  2126     by more modern 'type_notation', 'notation' and 'abbreviation',
  2127     which are independent of this issue.
  2128 
  2129   - 'translations' require markup within the AST; the term syntax
  2130     provides the following special forms:
  2131 
  2132       CONST c   -- produces syntax version of constant c from context
  2133       XCONST c  -- literally c, checked as constant from context
  2134       c         -- literally c, if declared by 'syntax'
  2135 
  2136     Plain identifiers are treated as AST variables -- occasionally the
  2137     system indicates accidental variables via the error "rhs contains
  2138     extra variables".
  2139 
  2140     Type classes and type constructors are marked according to their
  2141     concrete syntax.  Some old translations rules need to be written
  2142     for the "type" category, using type constructor application
  2143     instead of pseudo-term application of the default category
  2144     "logic".
  2145 
  2146   - 'parse_translation' etc. in ML may use the following
  2147     antiquotations:
  2148 
  2149       @{class_syntax c}   -- type class c within parse tree / AST
  2150       @{term_syntax c}    -- type constructor c within parse tree / AST
  2151       @{const_syntax c}   -- ML version of "CONST c" above
  2152       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  2153 
  2154   - Literal types within 'typed_print_translations', i.e. those *not*
  2155     represented as pseudo-terms are represented verbatim.  Use @{class
  2156     c} or @{type_name c} here instead of the above syntax
  2157     antiquotations.
  2158 
  2159 Note that old non-authentic syntax was based on unqualified base
  2160 names, so all of the above "constant" names would coincide.  Recall
  2161 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  2162 diagnose syntax problems.
  2163 
  2164 * Type constructors admit general mixfix syntax, not just infix.
  2165 
  2166 * Concrete syntax may be attached to local entities without a proof
  2167 body, too.  This works via regular mixfix annotations for 'fix',
  2168 'def', 'obtain' etc. or via the explicit 'write' command, which is
  2169 similar to the 'notation' command in theory specifications.
  2170 
  2171 * Discontinued unnamed infix syntax (legacy feature for many years) --
  2172 need to specify constant name and syntax separately.  Internal ML
  2173 datatype constructors have been renamed from InfixName to Infix etc.
  2174 Minor INCOMPATIBILITY.
  2175 
  2176 * Schematic theorem statements need to be explicitly markup as such,
  2177 via commands 'schematic_lemma', 'schematic_theorem',
  2178 'schematic_corollary'.  Thus the relevance of the proof is made
  2179 syntactically clear, which impacts performance in a parallel or
  2180 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  2181 
  2182 * Use of cumulative prems via "!" in some proof methods has been
  2183 discontinued (old legacy feature).
  2184 
  2185 * References 'trace_simp' and 'debug_simp' have been replaced by
  2186 configuration options stored in the context. Enabling tracing (the
  2187 case of debugging is similar) in proofs works via
  2188 
  2189   using [[trace_simp = true]]
  2190 
  2191 Tracing is then active for all invocations of the simplifier in
  2192 subsequent goal refinement steps. Tracing may also still be enabled or
  2193 disabled via the ProofGeneral settings menu.
  2194 
  2195 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  2196 'hide_fact' replace the former 'hide' KIND command.  Minor
  2197 INCOMPATIBILITY.
  2198 
  2199 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  2200 more efficient than combinations with -q1 or -q2.
  2201 
  2202 
  2203 *** Pure ***
  2204 
  2205 * Proofterms record type-class reasoning explicitly, using the
  2206 "unconstrain" operation internally.  This eliminates all sort
  2207 constraints from a theorem and proof, introducing explicit
  2208 OFCLASS-premises.  On the proof term level, this operation is
  2209 automatically applied at theorem boundaries, such that closed proofs
  2210 are always free of sort constraints.  INCOMPATIBILITY for tools that
  2211 inspect proof terms.
  2212 
  2213 * Local theory specifications may depend on extra type variables that
  2214 are not present in the result type -- arguments TYPE('a) :: 'a itself
  2215 are added internally.  For example:
  2216 
  2217   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  2218 
  2219 * Predicates of locales introduced by classes carry a mandatory
  2220 "class" prefix.  INCOMPATIBILITY.
  2221 
  2222 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  2223 
  2224 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  2225 'class' instead.
  2226 
  2227 * Command 'code_reflect' allows to incorporate generated ML code into
  2228 runtime environment; replaces immature code_datatype antiquotation.
  2229 INCOMPATIBILITY.
  2230 
  2231 * Code generator: simple concept for abstract datatypes obeying
  2232 invariants.
  2233 
  2234 * Code generator: details of internal data cache have no impact on the
  2235 user space functionality any longer.
  2236 
  2237 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  2238 subgoals.  This is more appropriate for interpretations with 'where'.
  2239 INCOMPATIBILITY.
  2240 
  2241 * Command 'example_proof' opens an empty proof body.  This allows to
  2242 experiment with Isar, without producing any persistent result.
  2243 
  2244 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  2245 within a local theory context, with explicit checking of the
  2246 constructors involved (in contrast to the raw 'syntax' versions).
  2247 
  2248 * Commands 'types' and 'typedecl' now work within a local theory
  2249 context -- without introducing dependencies on parameters or
  2250 assumptions, which is not possible in Isabelle/Pure.
  2251 
  2252 * Command 'defaultsort' has been renamed to 'default_sort', it works
  2253 within a local theory context.  Minor INCOMPATIBILITY.
  2254 
  2255 
  2256 *** HOL ***
  2257 
  2258 * Command 'typedef' now works within a local theory context -- without
  2259 introducing dependencies on parameters or assumptions, which is not
  2260 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  2261 contain multiple interpretations of local typedefs (with different
  2262 non-emptiness proofs), even in a global theory context.
  2263 
  2264 * New package for quotient types.  Commands 'quotient_type' and
  2265 'quotient_definition' may be used for defining types and constants by
  2266 quotient constructions.  An example is the type of integers created by
  2267 quotienting pairs of natural numbers:
  2268 
  2269   fun
  2270     intrel :: "(nat * nat) => (nat * nat) => bool"
  2271   where
  2272     "intrel (x, y) (u, v) = (x + v = u + y)"
  2273 
  2274   quotient_type int = "nat * nat" / intrel
  2275     by (auto simp add: equivp_def expand_fun_eq)
  2276 
  2277   quotient_definition
  2278     "0::int" is "(0::nat, 0::nat)"
  2279 
  2280 The method "lifting" can be used to lift of theorems from the
  2281 underlying "raw" type to the quotient type.  The example
  2282 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  2283 construction and provides a reasoning infrastructure for finite sets.
  2284 
  2285 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  2286 clash with new theory Quotient in Main HOL.
  2287 
  2288 * Moved the SMT binding into the main HOL session, eliminating
  2289 separate HOL-SMT session.
  2290 
  2291 * List membership infix mem operation is only an input abbreviation.
  2292 INCOMPATIBILITY.
  2293 
  2294 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  2295 for future developements; former Library/Word.thy is still present in
  2296 the AFP entry RSAPPS.
  2297 
  2298 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  2299 longer shadowed.  INCOMPATIBILITY.
  2300 
  2301 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  2302 INCOMPATIBILITY.
  2303 
  2304 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  2305 INCOMPATIBILITY.
  2306 
  2307 * Dropped normalizing_semiring etc; use the facts in semiring classes
  2308 instead.  INCOMPATIBILITY.
  2309 
  2310 * Dropped several real-specific versions of lemmas about floor and
  2311 ceiling; use the generic lemmas from theory "Archimedean_Field"
  2312 instead.  INCOMPATIBILITY.
  2313 
  2314   floor_number_of_eq         ~> floor_number_of
  2315   le_floor_eq_number_of      ~> number_of_le_floor
  2316   le_floor_eq_zero           ~> zero_le_floor
  2317   le_floor_eq_one            ~> one_le_floor
  2318   floor_less_eq_number_of    ~> floor_less_number_of
  2319   floor_less_eq_zero         ~> floor_less_zero
  2320   floor_less_eq_one          ~> floor_less_one
  2321   less_floor_eq_number_of    ~> number_of_less_floor
  2322   less_floor_eq_zero         ~> zero_less_floor
  2323   less_floor_eq_one          ~> one_less_floor
  2324   floor_le_eq_number_of      ~> floor_le_number_of
  2325   floor_le_eq_zero           ~> floor_le_zero
  2326   floor_le_eq_one            ~> floor_le_one
  2327   floor_subtract_number_of   ~> floor_diff_number_of
  2328   floor_subtract_one         ~> floor_diff_one
  2329   ceiling_number_of_eq       ~> ceiling_number_of
  2330   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  2331   ceiling_le_zero_eq         ~> ceiling_le_zero
  2332   ceiling_le_eq_one          ~> ceiling_le_one
  2333   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  2334   less_ceiling_eq_zero       ~> zero_less_ceiling
  2335   less_ceiling_eq_one        ~> one_less_ceiling
  2336   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  2337   ceiling_less_eq_zero       ~> ceiling_less_zero
  2338   ceiling_less_eq_one        ~> ceiling_less_one
  2339   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  2340   le_ceiling_eq_zero         ~> zero_le_ceiling
  2341   le_ceiling_eq_one          ~> one_le_ceiling
  2342   ceiling_subtract_number_of ~> ceiling_diff_number_of
  2343   ceiling_subtract_one       ~> ceiling_diff_one
  2344 
  2345 * Theory "Finite_Set": various folding_XXX locales facilitate the
  2346 application of the various fold combinators on finite sets.
  2347 
  2348 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  2349 provides abstract red-black tree type which is backed by "RBT_Impl" as
  2350 implementation.  INCOMPATIBILTY.
  2351 
  2352 * Theory Library/Coinductive_List has been removed -- superseded by
  2353 AFP/thys/Coinductive.
  2354 
  2355 * Theory PReal, including the type "preal" and related operations, has
  2356 been removed.  INCOMPATIBILITY.
  2357 
  2358 * Real: new development using Cauchy Sequences.
  2359 
  2360 * Split off theory "Big_Operators" containing setsum, setprod,
  2361 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  2362 
  2363 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  2364 "Int" etc.  INCOMPATIBILITY.
  2365 
  2366 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  2367 
  2368 * New set of rules "ac_simps" provides combined assoc / commute
  2369 rewrites for all interpretations of the appropriate generic locales.
  2370 
  2371 * Renamed theory "OrderedGroup" to "Groups" and split theory
  2372 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  2373 appropriate and more consistent names suitable for name prefixes
  2374 within the HOL theories.  INCOMPATIBILITY.
  2375 
  2376 * Some generic constants have been put to appropriate theories:
  2377   - less_eq, less: Orderings
  2378   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  2379   - inverse, divide: Rings
  2380 INCOMPATIBILITY.
  2381 
  2382 * More consistent naming of type classes involving orderings (and
  2383 lattices):
  2384 
  2385     lower_semilattice                   ~> semilattice_inf
  2386     upper_semilattice                   ~> semilattice_sup
  2387 
  2388     dense_linear_order                  ~> dense_linorder
  2389 
  2390     pordered_ab_group_add               ~> ordered_ab_group_add
  2391     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  2392     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  2393     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  2394     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  2395     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  2396     pordered_cancel_semiring            ~> ordered_cancel_semiring
  2397     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  2398     pordered_comm_ring                  ~> ordered_comm_ring
  2399     pordered_comm_semiring              ~> ordered_comm_semiring
  2400     pordered_ring                       ~> ordered_ring
  2401     pordered_ring_abs                   ~> ordered_ring_abs
  2402     pordered_semiring                   ~> ordered_semiring
  2403 
  2404     ordered_ab_group_add                ~> linordered_ab_group_add
  2405     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  2406     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  2407     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  2408     ordered_field                       ~> linordered_field
  2409     ordered_field_no_lb                 ~> linordered_field_no_lb
  2410     ordered_field_no_ub                 ~> linordered_field_no_ub
  2411     ordered_field_dense_linear_order    ~> dense_linordered_field
  2412     ordered_idom                        ~> linordered_idom
  2413     ordered_ring                        ~> linordered_ring
  2414     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  2415     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  2416     ordered_ring_strict                 ~> linordered_ring_strict
  2417     ordered_semidom                     ~> linordered_semidom
  2418     ordered_semiring                    ~> linordered_semiring
  2419     ordered_semiring_1                  ~> linordered_semiring_1
  2420     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  2421     ordered_semiring_strict             ~> linordered_semiring_strict
  2422 
  2423   The following slightly odd type classes have been moved to a
  2424   separate theory Library/Lattice_Algebras:
  2425 
  2426     lordered_ab_group_add               ~> lattice_ab_group_add
  2427     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  2428     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  2429     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  2430     lordered_ring                       ~> lattice_ring
  2431 
  2432 INCOMPATIBILITY.
  2433 
  2434 * Refined field classes:
  2435   - classes division_ring_inverse_zero, field_inverse_zero,
  2436     linordered_field_inverse_zero include rule inverse 0 = 0 --
  2437     subsumes former division_by_zero class;
  2438   - numerous lemmas have been ported from field to division_ring.
  2439 INCOMPATIBILITY.
  2440 
  2441 * Refined algebra theorem collections:
  2442   - dropped theorem group group_simps, use algebra_simps instead;
  2443   - dropped theorem group ring_simps, use field_simps instead;
  2444   - proper theorem collection field_simps subsumes former theorem
  2445     groups field_eq_simps and field_simps;
  2446   - dropped lemma eq_minus_self_iff which is a duplicate for
  2447     equal_neg_zero.
  2448 INCOMPATIBILITY.
  2449 
  2450 * Theory Finite_Set and List: some lemmas have been generalized from
  2451 sets to lattices:
  2452 
  2453   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  2454   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  2455   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  2456   union_Union_fold_union        ~> sup_Sup_fold_sup
  2457   Inter_fold_inter              ~> Inf_fold_inf
  2458   Union_fold_union              ~> Sup_fold_sup
  2459   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  2460   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  2461   INTER_fold_inter              ~> INFI_fold_inf
  2462   UNION_fold_union              ~> SUPR_fold_sup
  2463 
  2464 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  2465 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  2466 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  2467 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  2468 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  2469 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  2470 
  2471 * Reorganized theory Multiset: swapped notation of pointwise and
  2472 multiset order:
  2473 
  2474   - pointwise ordering is instance of class order with standard syntax
  2475     <= and <;
  2476   - multiset ordering has syntax <=# and <#; partial order properties
  2477     are provided by means of interpretation with prefix
  2478     multiset_order;
  2479   - less duplication, less historical organization of sections,
  2480     conversion from associations lists to multisets, rudimentary code
  2481     generation;
  2482   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  2483     if needed.
  2484 
  2485 Renamed:
  2486 
  2487   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  2488   multi_count_ext  ~>  multiset_ext
  2489   diff_union_inverse2  ~>  diff_union_cancelR
  2490 
  2491 INCOMPATIBILITY.
  2492 
  2493 * Theory Permutation: replaced local "remove" by List.remove1.
  2494 
  2495 * Code generation: ML and OCaml code is decorated with signatures.
  2496 
  2497 * Theory List: added transpose.
  2498 
  2499 * Library/Nat_Bijection.thy is a collection of bijective functions
  2500 between nat and other types, which supersedes the older libraries
  2501 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2502 
  2503   Constants:
  2504   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2505   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2506   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2507   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2508   Countable.pair_encode           ~> prod_encode
  2509   NatIso.prod2nat                 ~> prod_encode
  2510   NatIso.nat2prod                 ~> prod_decode
  2511   NatIso.sum2nat                  ~> sum_encode
  2512   NatIso.nat2sum                  ~> sum_decode
  2513   NatIso.list2nat                 ~> list_encode
  2514   NatIso.nat2list                 ~> list_decode
  2515   NatIso.set2nat                  ~> set_encode
  2516   NatIso.nat2set                  ~> set_decode
  2517 
  2518   Lemmas:
  2519   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2520   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2521   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2522   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2523   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2524   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2525   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2526   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2527   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2528   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2529   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2530   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2531   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2532 
  2533 * Sledgehammer:
  2534   - Renamed ATP commands:
  2535     atp_info     ~> sledgehammer running_atps
  2536     atp_kill     ~> sledgehammer kill_atps
  2537     atp_messages ~> sledgehammer messages
  2538     atp_minimize ~> sledgehammer minimize
  2539     print_atps   ~> sledgehammer available_atps
  2540     INCOMPATIBILITY.
  2541   - Added user's manual ("isabelle doc sledgehammer").
  2542   - Added option syntax and "sledgehammer_params" to customize
  2543     Sledgehammer's behavior.  See the manual for details.
  2544   - Modified the Isar proof reconstruction code so that it produces
  2545     direct proofs rather than proofs by contradiction.  (This feature
  2546     is still experimental.)
  2547   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2548     full-typed mode.
  2549   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2550 
  2551 * Nitpick:
  2552   - Added and implemented "binary_ints" and "bits" options.
  2553   - Added "std" option and implemented support for nonstandard models.
  2554   - Added and implemented "finitize" option to improve the precision
  2555     of infinite datatypes based on a monotonicity analysis.
  2556   - Added support for quotient types.
  2557   - Added support for "specification" and "ax_specification"
  2558     constructs.
  2559   - Added support for local definitions (for "function" and
  2560     "termination" proofs).
  2561   - Added support for term postprocessors.
  2562   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2563   - Improved efficiency of "destroy_constrs" optimization.
  2564   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2565     record getters.
  2566   - Fixed soundness bug related to higher-order constructors.
  2567   - Fixed soundness bug when "full_descrs" is enabled.
  2568   - Improved precision of set constructs.
  2569   - Added "atoms" option.
  2570   - Added cache to speed up repeated Kodkod invocations on the same
  2571     problems.
  2572   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2573     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2574     "SAT4J_Light".  INCOMPATIBILITY.
  2575   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2576     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2577   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2578 
  2579 * Method "induct" now takes instantiations of the form t, where t is not
  2580   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2581   If this is not intended, t has to be enclosed in parentheses.
  2582   By default, the equalities generated by definitional instantiations
  2583   are pre-simplified, which may cause parameters of inductive cases
  2584   to disappear, or may even delete some of the inductive cases.
  2585   Use "induct (no_simp)" instead of "induct" to restore the old
  2586   behaviour. The (no_simp) option is also understood by the "cases"
  2587   and "nominal_induct" methods, which now perform pre-simplification, too.
  2588   INCOMPATIBILITY.
  2589 
  2590 
  2591 *** HOLCF ***
  2592 
  2593 * Variable names in lemmas generated by the domain package have
  2594 changed; the naming scheme is now consistent with the HOL datatype
  2595 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2596 
  2597 * The domain package no longer defines the function "foo_copy" for
  2598 recursive domain "foo".  The reach lemma is now stated directly in
  2599 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2600 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2601 
  2602 * Most definedness lemmas generated by the domain package (previously
  2603 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2604 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2605 Proofs that used definedness lemmas as intro rules may break,
  2606 potential INCOMPATIBILITY.
  2607 
  2608 * Induction and casedist rules generated by the domain package now
  2609 declare proper case_names (one called "bottom", and one named for each
  2610 constructor).  INCOMPATIBILITY.
  2611 
  2612 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2613 rules are generated for each domain, INCOMPATIBILITY.
  2614 
  2615   foo_bar.reach       ~> foo.reach  bar.reach
  2616   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2617 
  2618 * Some lemmas generated by the domain package have been renamed for
  2619 consistency with the datatype package, INCOMPATIBILITY.
  2620 
  2621   foo.ind        ~> foo.induct
  2622   foo.finite_ind ~> foo.finite_induct
  2623   foo.coind      ~> foo.coinduct
  2624   foo.casedist   ~> foo.exhaust
  2625   foo.exhaust    ~> foo.nchotomy
  2626 
  2627 * For consistency with other definition packages, the fixrec package
  2628 now generates qualified theorem names, INCOMPATIBILITY.
  2629 
  2630   foo_simps  ~> foo.simps
  2631   foo_unfold ~> foo.unfold
  2632   foo_induct ~> foo.induct
  2633 
  2634 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2635 method and internal fixrec proofs now use the default simpset instead.
  2636 INCOMPATIBILITY.
  2637 
  2638 * The "contlub" predicate has been removed.  Proof scripts should use
  2639 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2640 
  2641 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2642 
  2643 * The constants cpair, cfst, and csnd have been removed in favor of
  2644 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2645 
  2646 
  2647 *** ML ***
  2648 
  2649 * Antiquotations for basic formal entities:
  2650 
  2651     @{class NAME}         -- type class
  2652     @{class_syntax NAME}  -- syntax representation of the above
  2653 
  2654     @{type_name NAME}     -- logical type
  2655     @{type_abbrev NAME}   -- type abbreviation
  2656     @{nonterminal NAME}   -- type of concrete syntactic category
  2657     @{type_syntax NAME}   -- syntax representation of any of the above
  2658 
  2659     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2660     @{const_abbrev NAME}  -- abbreviated constant
  2661     @{const_syntax NAME}  -- syntax representation of any of the above
  2662 
  2663 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2664 syntax constant (cf. 'syntax' command).
  2665 
  2666 * Antiquotation @{make_string} inlines a function to print arbitrary
  2667 values similar to the ML toplevel.  The result is compiler dependent
  2668 and may fall back on "?" in certain situations.
  2669 
  2670 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2671 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2672 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2673 not work with the asynchronous Isar document model.
  2674 
  2675 * Configuration options now admit dynamic default values, depending on
  2676 the context or even global references.
  2677 
  2678 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2679 uses an efficient external library if available (for Poly/ML).
  2680 
  2681 * Renamed some important ML structures, while keeping the old names
  2682 for some time as aliases within the structure Legacy:
  2683 
  2684   OuterKeyword  ~>  Keyword
  2685   OuterLex      ~>  Token
  2686   OuterParse    ~>  Parse
  2687   OuterSyntax   ~>  Outer_Syntax
  2688   PrintMode     ~>  Print_Mode
  2689   SpecParse     ~>  Parse_Spec
  2690   ThyInfo       ~>  Thy_Info
  2691   ThyLoad       ~>  Thy_Load
  2692   ThyOutput     ~>  Thy_Output
  2693   TypeInfer     ~>  Type_Infer
  2694 
  2695 Note that "open Legacy" simplifies porting of sources, but forgetting
  2696 to remove it again will complicate porting again in the future.
  2697 
  2698 * Most operations that refer to a global context are named
  2699 accordingly, e.g. Simplifier.global_context or
  2700 ProofContext.init_global.  There are some situations where a global
  2701 context actually works, but under normal circumstances one needs to
  2702 pass the proper local context through the code!
  2703 
  2704 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2705 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2706 Pretty.pp argument to merge, which is absent in the standard
  2707 Theory_Data version.
  2708 
  2709 * Sorts.certify_sort and derived "cert" operations for types and terms
  2710 no longer minimize sorts.  Thus certification at the boundary of the
  2711 inference kernel becomes invariant under addition of class relations,
  2712 which is an important monotonicity principle.  Sorts are now minimized
  2713 in the syntax layer only, at the boundary between the end-user and the
  2714 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2715 explicitly in rare situations.
  2716 
  2717 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2718 emphasize that this is in no way a standard operation.
  2719 INCOMPATIBILITY.
  2720 
  2721 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2722 usual for resolution.  Rare INCOMPATIBILITY.
  2723 
  2724 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2725 to emphasize that these only work in a global situation (which is
  2726 quite rare).
  2727 
  2728 * Curried take and drop in library.ML; negative length is interpreted
  2729 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2730 
  2731 * Proof terms: type substitutions on proof constants now use canonical
  2732 order of type variables.  INCOMPATIBILITY for tools working with proof
  2733 terms.
  2734 
  2735 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2736 may no longer carry premises.  User-level specifications are
  2737 transformed accordingly by Thm.add_axiom/add_def.
  2738 
  2739 
  2740 *** System ***
  2741 
  2742 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2743 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2744 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2745 
  2746 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2747 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2748 respectively.
  2749 
  2750 * Old lib/scripts/polyml-platform is superseded by the
  2751 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2752 variant, even on a 64 bit machine.  The following example setting
  2753 prefers 64 bit if available:
  2754 
  2755   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2756 
  2757 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2758 Isabelle/Scala layer for advanced prover interaction and integration.
  2759 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2760 component.
  2761 
  2762 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2763 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2764 similar to the default assignment of the document preparation system
  2765 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2766 provides some operations for direct access to the font without asking
  2767 the user for manual installation.
  2768 
  2769 
  2770 
  2771 New in Isabelle2009-1 (December 2009)
  2772 -------------------------------------
  2773 
  2774 *** General ***
  2775 
  2776 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2777 one backslash should be used, even in ML sources.
  2778 
  2779 
  2780 *** Pure ***
  2781 
  2782 * Locale interpretation propagates mixins along the locale hierarchy.
  2783 The currently only available mixins are the equations used to map
  2784 local definitions to terms of the target domain of an interpretation.
  2785 
  2786 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2787 loc" to print all interpretations of locale "loc" in the theory.
  2788 Interpretations in proofs are not shown.
  2789 
  2790 * Thoroughly revised locales tutorial.  New section on conditional
  2791 interpretation.
  2792 
  2793 * On instantiation of classes, remaining undefined class parameters
  2794 are formally declared.  INCOMPATIBILITY.
  2795 
  2796 
  2797 *** Document preparation ***
  2798 
  2799 * New generalized style concept for printing terms: @{foo (style) ...}
  2800 instead of @{foo_style style ...}  (old form is still retained for
  2801 backward compatibility).  Styles can be also applied for
  2802 antiquotations prop, term_type and typeof.
  2803 
  2804 
  2805 *** HOL ***
  2806 
  2807 * New proof method "smt" for a combination of first-order logic with
  2808 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2809 fixed-size bitvectors; there is also basic support for higher-order
  2810 features (esp. lambda abstractions).  It is an incomplete decision
  2811 procedure based on external SMT solvers using the oracle mechanism;
  2812 for the SMT solver Z3, this method is proof-producing.  Certificates
  2813 are provided to avoid calling the external solvers solely for
  2814 re-checking proofs.  Due to a remote SMT service there is no need for
  2815 installing SMT solvers locally.  See src/HOL/SMT.
  2816 
  2817 * New commands to load and prove verification conditions generated by
  2818 the Boogie program verifier or derived systems (e.g. the Verifying C
  2819 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2820 
  2821 * New counterexample generator tool 'nitpick' based on the Kodkod
  2822 relational model finder.  See src/HOL/Tools/Nitpick and
  2823 src/HOL/Nitpick_Examples.
  2824 
  2825 * New commands 'code_pred' and 'values' to invoke the predicate
  2826 compiler and to enumerate values of inductive predicates.
  2827 
  2828 * A tabled implementation of the reflexive transitive closure.
  2829 
  2830 * New implementation of quickcheck uses generic code generator;
  2831 default generators are provided for all suitable HOL types, records
  2832 and datatypes.  Old quickcheck can be re-activated importing theory
  2833 Library/SML_Quickcheck.
  2834 
  2835 * New testing tool Mirabelle for automated proof tools.  Applies
  2836 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2837 every proof step in a theory.  To be used in batch mode via the
  2838 "mirabelle" utility.
  2839 
  2840 * New proof method "sos" (sum of squares) for nonlinear real
  2841 arithmetic (originally due to John Harison). It requires theory
  2842 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2843 works well in practice on quantifier-free real arithmetic with +, -,
  2844 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2845 inequalities between polynomials.  It makes use of external
  2846 semidefinite programming solvers.  Method "sos" generates a
  2847 certificate that can be pasted into the proof thus avoiding the need
  2848 to call an external tool every time the proof is checked.  See
  2849 src/HOL/Library/Sum_Of_Squares.
  2850 
  2851 * New method "linarith" invokes existing linear arithmetic decision
  2852 procedure only.
  2853 
  2854 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2855 
  2856 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2857 Causes full type information to be output to the ATPs.  This slows
  2858 ATPs down considerably but eliminates a source of unsound "proofs"
  2859 that fail later.
  2860 
  2861 * New method "metisFT": A version of metis that uses full type
  2862 information in order to avoid failures of proof reconstruction.
  2863 
  2864 * New evaluator "approximate" approximates an real valued term using
  2865 the same method as the approximation method.
  2866 
  2867 * Method "approximate" now supports arithmetic expressions as
  2868 boundaries of intervals and implements interval splitting and Taylor
  2869 series expansion.
  2870 
  2871 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2872 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2873 
  2874 * New theory SupInf of the supremum and infimum operators for sets of
  2875 reals.
  2876 
  2877 * New theory Probability, which contains a development of measure
  2878 theory, eventually leading to Lebesgue integration and probability.
  2879 
  2880 * Extended Multivariate Analysis to include derivation and Brouwer's
  2881 fixpoint theorem.
  2882 
  2883 * Reorganization of number theory, INCOMPATIBILITY:
  2884   - new number theory development for nat and int, in theories Divides
  2885     and GCD as well as in new session Number_Theory
  2886   - some constants and facts now suffixed with _nat and _int
  2887     accordingly
  2888   - former session NumberTheory now named Old_Number_Theory, including
  2889     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2890   - moved theory Pocklington from src/HOL/Library to
  2891     src/HOL/Old_Number_Theory
  2892 
  2893 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2894 lcm of finite and infinite sets. It is shown that they form a complete
  2895 lattice.
  2896 
  2897 * Class semiring_div requires superclass no_zero_divisors and proof of
  2898 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2899 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2900 generalized to class semiring_div, subsuming former theorems
  2901 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2902 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2903 INCOMPATIBILITY.
  2904 
  2905 * Refinements to lattice classes and sets:
  2906   - less default intro/elim rules in locale variant, more default
  2907     intro/elim rules in class variant: more uniformity
  2908   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2909     le_inf_iff
  2910   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2911     sup_aci)
  2912   - renamed ACI to inf_sup_aci
  2913   - new class "boolean_algebra"
  2914   - class "complete_lattice" moved to separate theory
  2915     "Complete_Lattice"; corresponding constants (and abbreviations)
  2916     renamed and with authentic syntax:
  2917     Set.Inf ~>    Complete_Lattice.Inf
  2918     Set.Sup ~>    Complete_Lattice.Sup
  2919     Set.INFI ~>   Complete_Lattice.INFI
  2920     Set.SUPR ~>   Complete_Lattice.SUPR
  2921     Set.Inter ~>  Complete_Lattice.Inter
  2922     Set.Union ~>  Complete_Lattice.Union
  2923     Set.INTER ~>  Complete_Lattice.INTER
  2924     Set.UNION ~>  Complete_Lattice.UNION
  2925   - authentic syntax for
  2926     Set.Pow
  2927     Set.image
  2928   - mere abbreviations:
  2929     Set.empty               (for bot)
  2930     Set.UNIV                (for top)
  2931     Set.inter               (for inf, formerly Set.Int)
  2932     Set.union               (for sup, formerly Set.Un)
  2933     Complete_Lattice.Inter  (for Inf)
  2934     Complete_Lattice.Union  (for Sup)
  2935     Complete_Lattice.INTER  (for INFI)
  2936     Complete_Lattice.UNION  (for SUPR)
  2937   - object-logic definitions as far as appropriate
  2938 
  2939 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2940 Un_subset_iff are explicitly deleted as default simp rules; then also
  2941 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2942 deleted to achieve the desired effect.
  2943 
  2944 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2945 rules by default any longer; the same applies to min_max.inf_absorb1
  2946 etc.  INCOMPATIBILITY.
  2947 
  2948 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2949 pred_set_conv by default.  INCOMPATIBILITY.
  2950 
  2951 * Power operations on relations and functions are now one dedicated
  2952 constant "compow" with infix syntax "^^".  Power operation on
  2953 multiplicative monoids retains syntax "^" and is now defined generic
  2954 in class power.  INCOMPATIBILITY.
  2955 
  2956 * Relation composition "R O S" now has a more standard argument order:
  2957 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2958 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2959 break, since the O_assoc rule was not rewritten like this.  Fix using
  2960 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2961 
  2962 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2963 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2964 INCOMPATIBILITY.
  2965 
  2966 * Most rules produced by inductive and datatype package have mandatory
  2967 prefixes.  INCOMPATIBILITY.
  2968 
  2969 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2970 the attribute of the same name.  Each of the theorems in the list
  2971 DERIV_intros assumes composition with an additional function and
  2972 matches a variable to the derivative, which has to be solved by the
  2973 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2974 of most elementary terms.  Former Maclauren.DERIV_tac and
  2975 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2976 INCOMPATIBILITY.
  2977 
  2978 * Code generator attributes follow the usual underscore convention:
  2979     code_unfold     replaces    code unfold
  2980     code_post       replaces    code post
  2981     etc.
  2982   INCOMPATIBILITY.
  2983 
  2984 * Renamed methods:
  2985     sizechange -> size_change
  2986     induct_scheme -> induction_schema
  2987   INCOMPATIBILITY.
  2988 
  2989 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2990 INCOMPATIBILITY, use "undefined" directly.
  2991 
  2992 * Renamed theorems:
  2993     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2994     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2995     Suc_plus1 -> Suc_eq_plus1
  2996     *anti_sym -> *antisym*
  2997     vector_less_eq_def -> vector_le_def
  2998   INCOMPATIBILITY.
  2999 
  3000 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  3001 INCOMPATIBILITY.
  3002 
  3003 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  3004 INCOMPATIBILITY.
  3005 
  3006 
  3007 *** HOLCF ***
  3008 
  3009 * Theory Representable defines a class "rep" of domains that are
  3010 representable (via an ep-pair) in the universal domain type "udom".
  3011 Instances are provided for all type constructors defined in HOLCF.
  3012 
  3013 * The 'new_domain' command is a purely definitional version of the
  3014 domain package, for representable domains.  Syntax is identical to the
  3015 old domain package.  The 'new_domain' package also supports indirect
  3016 recursion using previously-defined type constructors.  See
  3017 src/HOLCF/ex/New_Domain.thy for examples.
  3018 
  3019 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  3020 on the left-hand side of an equation, and then performs
  3021 simplification.  Rewriting is done using rules declared with the
  3022 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  3023 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  3024 
  3025 * The pattern-match compiler in 'fixrec' can now handle constructors
  3026 with HOL function types.  Pattern-match combinators for the Pair
  3027 constructor are pre-configured.
  3028 
  3029 * The 'fixrec' package now produces better fixed-point induction rules
  3030 for mutually-recursive definitions:  Induction rules have conclusions
  3031 of the form "P foo bar" instead of "P <foo, bar>".
  3032 
  3033 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  3034 been renamed to "below".  The name "below" now replaces "less" in many
  3035 theorem names.  (Legacy theorem names using "less" are still supported
  3036 as well.)
  3037 
  3038 * The 'fixrec' package now supports "bottom patterns".  Bottom
  3039 patterns can be used to generate strictness rules, or to make
  3040 functions more strict (much like the bang-patterns supported by the
  3041 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  3042 examples.
  3043 
  3044 
  3045 *** ML ***
  3046 
  3047 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  3048 errors and run-time exceptions, including detailed source positions.
  3049 
  3050 * Structure Name_Space (formerly NameSpace) now manages uniquely
  3051 identified entries, with some additional information such as source
  3052 position, logical grouping etc.
  3053 
  3054 * Theory and context data is now introduced by the simplified and
  3055 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  3056 to be pure, but the old TheoryDataFun for mutable data (with explicit
  3057 copy operation) is still available for some time.
  3058 
  3059 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  3060 provides a high-level programming interface to synchronized state
  3061 variables with atomic update.  This works via pure function
  3062 application within a critical section -- its runtime should be as
  3063 short as possible; beware of deadlocks if critical code is nested,
  3064 either directly or indirectly via other synchronized variables!
  3065 
  3066 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  3067 wraps raw ML references, explicitly indicating their non-thread-safe
  3068 behaviour.  The Isar toplevel keeps this structure open, to
  3069 accommodate Proof General as well as quick and dirty interactive
  3070 experiments with references.
  3071 
  3072 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  3073 parallel tactical reasoning.
  3074 
  3075 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  3076 are similar to SUBPROOF, but are slightly more flexible: only the
  3077 specified parts of the subgoal are imported into the context, and the
  3078 body tactic may introduce new subgoals and schematic variables.
  3079 
  3080 * Old tactical METAHYPS, which does not observe the proof context, has
  3081 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  3082 or Subgoal.FOCUS etc.
  3083 
  3084 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  3085 functors have their own ML name space there is no point to mark them
  3086 separately.)  Minor INCOMPATIBILITY.
  3087 
  3088 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  3089 
  3090 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  3091 INCOMPATIBILITY.
  3092 
  3093 * Operations of structure Skip_Proof no longer require quick_and_dirty
  3094 mode, which avoids critical setmp.
  3095 
  3096 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  3097 combinators for "args".  INCOMPATIBILITY, need to use simplified
  3098 Attrib/Method.setup introduced in Isabelle2009.
  3099 
  3100 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  3101 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  3102 last resort.  INCOMPATIBILITY.
  3103 
  3104 * Display.pretty_thm now requires a proper context (cf. former
  3105 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  3106 or even Display.pretty_thm_without_context as last resort.
  3107 INCOMPATIBILITY.
  3108 
  3109 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  3110 Syntax.pretty_typ/term directly, preferably with proper context
  3111 instead of global theory.
  3112 
  3113 
  3114 *** System ***
  3115 
  3116 * Further fine tuning of parallel proof checking, scales up to 8 cores
  3117 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  3118 usedir option -q.
  3119 
  3120 * Support for additional "Isabelle components" via etc/components, see
  3121 also the system manual.
  3122 
  3123 * The isabelle makeall tool now operates on all components with
  3124 IsaMakefile, not just hardwired "logics".
  3125 
  3126 * Removed "compress" option from isabelle-process and isabelle usedir;
  3127 this is always enabled.
  3128 
  3129 * Discontinued support for Poly/ML 4.x versions.
  3130 
  3131 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  3132 on a given logic image.  This requires the lighttpd webserver and is
  3133 currently supported on Linux only.
  3134 
  3135 
  3136 
  3137 New in Isabelle2009 (April 2009)
  3138 --------------------------------
  3139 
  3140 *** General ***
  3141 
  3142 * Simplified main Isabelle executables, with less surprises on
  3143 case-insensitive file-systems (such as Mac OS).
  3144 
  3145   - The main Isabelle tool wrapper is now called "isabelle" instead of
  3146     "isatool."
  3147 
  3148   - The former "isabelle" alias for "isabelle-process" has been
  3149     removed (should rarely occur to regular users).
  3150 
  3151   - The former "isabelle-interface" and its alias "Isabelle" have been
  3152     removed (interfaces are now regular Isabelle tools).
  3153 
  3154 Within scripts and make files, the Isabelle environment variables
  3155 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  3156 respectively.  (The latter are still available as legacy feature.)
  3157 
  3158 The old isabelle-interface wrapper could react in confusing ways if
  3159 the interface was uninstalled or changed otherwise.  Individual
  3160 interface tool configuration is now more explicit, see also the
  3161 Isabelle system manual.  In particular, Proof General is now available
  3162 via "isabelle emacs".
  3163 
  3164 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  3165 purge installed copies of Isabelle executables and re-run "isabelle
  3166 install -p ...", or use symlinks.
  3167 
  3168 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  3169 old ~/isabelle, which was slightly non-standard and apt to cause
  3170 surprises on case-insensitive file-systems (such as Mac OS).
  3171 
  3172 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  3173 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  3174 care is required when using older releases of Isabelle.  Note that
  3175 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  3176 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  3177 
  3178 * Proofs of fully specified statements are run in parallel on
  3179 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  3180 a regular 4-core machine, if the initial heap space is made reasonably
  3181 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  3182 
  3183 * The main reference manuals ("isar-ref", "implementation", and
  3184 "system") have been updated and extended.  Formally checked references
  3185 as hyperlinks are now available uniformly.
  3186 
  3187 
  3188 *** Pure ***
  3189 
  3190 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  3191 respects.  The most important changes are listed below.  See the
  3192 Tutorial on Locales ("locales" manual) for details.
  3193 
  3194 - In locale expressions, instantiation replaces renaming.  Parameters
  3195 must be declared in a for clause.  To aid compatibility with previous
  3196 parameter inheritance, in locale declarations, parameters that are not
  3197 'touched' (instantiation position "_" or omitted) are implicitly added
  3198 with their syntax at the beginning of the for clause.
  3199 
  3200 - Syntax from abbreviations and definitions in locales is available in
  3201 locale expressions and context elements.  The latter is particularly
  3202 useful in locale declarations.
  3203 
  3204 - More flexible mechanisms to qualify names generated by locale
  3205 expressions.  Qualifiers (prefixes) may be specified in locale
  3206 expressions, and can be marked as mandatory (syntax: "name!:") or
  3207 optional (syntax "name?:").  The default depends for plain "name:"
  3208 depends on the situation where a locale expression is used: in
  3209 commands 'locale' and 'sublocale' prefixes are optional, in
  3210 'interpretation' and 'interpret' prefixes are mandatory.  The old
  3211 implicit qualifiers derived from the parameter names of a locale are
  3212 no longer generated.
  3213 
  3214 - Command "sublocale l < e" replaces "interpretation l < e".  The
  3215 instantiation clause in "interpretation" and "interpret" (square
  3216 brackets) is no longer available.  Use locale expressions.
  3217 
  3218 - When converting proof scripts, mandatory qualifiers in
  3219 'interpretation' and 'interpret' should be retained by default, even
  3220 if this is an INCOMPATIBILITY compared to former behavior.  In the
  3221 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  3222 in locale expressions range over a single locale instance only.
  3223 
  3224 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  3225 In existing theorem specifications replace the includes element by the
  3226 respective context elements of the included locale, omitting those
  3227 that are already present in the theorem specification.  Multiple
  3228 assume elements of a locale should be replaced by a single one
  3229 involving the locale predicate.  In the proof body, declarations (most
  3230 notably theorems) may be regained by interpreting the respective
  3231 locales in the proof context as required (command "interpret").
  3232 
  3233 If using "includes" in replacement of a target solely because the
  3234 parameter types in the theorem are not as general as in the target,
  3235 consider declaring a new locale with additional type constraints on
  3236 the parameters (context element "constrains").
  3237 
  3238 - Discontinued "locale (open)".  INCOMPATIBILITY.
  3239 
  3240 - Locale interpretation commands no longer attempt to simplify goal.
  3241 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  3242 methods intro_locales and unfold_locales to clarify.
  3243 
  3244 - Locale interpretation commands no longer accept interpretation
  3245 attributes.  INCOMPATIBILITY.
  3246 
  3247 * Class declaration: so-called "base sort" must not be given in import
  3248 list any longer, but is inferred from the specification.  Particularly
  3249 in HOL, write
  3250 
  3251     class foo = ...
  3252 
  3253 instead of
  3254 
  3255     class foo = type + ...
  3256 
  3257 * Class target: global versions of theorems stemming do not carry a
  3258 parameter prefix any longer.  INCOMPATIBILITY.
  3259 
  3260 * Class 'instance' command no longer accepts attached definitions.
  3261 INCOMPATIBILITY, use proper 'instantiation' target instead.
  3262 
  3263 * Recovered hiding of consts, which was accidentally broken in
  3264 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  3265 makes c inaccessible; consider using ``hide (open) const c'' instead.
  3266 
  3267 * Slightly more coherent Pure syntax, with updated documentation in
  3268 isar-ref manual.  Removed locales meta_term_syntax and
  3269 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  3270 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  3271 directly in regular applications.
  3272 
  3273 * There is a new syntactic category "float_const" for signed decimal
  3274 fractions (e.g. 123.45 or -123.45).
  3275 
  3276 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  3277 interface with 'setup' command instead.
  3278 
  3279 * Command 'local_setup' is similar to 'setup', but operates on a local
  3280 theory context.
  3281 
  3282 * The 'axiomatization' command now only works within a global theory
  3283 context.  INCOMPATIBILITY.
  3284 
  3285 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  3286 hypotheses.  Sorts required in the course of reasoning need to be
  3287 covered by the constraints in the initial statement, completed by the
  3288 type instance information of the background theory.  Non-trivial sort
  3289 hypotheses, which rarely occur in practice, may be specified via
  3290 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  3291 
  3292   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  3293 
  3294 The result contains an implicit sort hypotheses as before --
  3295 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  3296 normalization.
  3297 
  3298 * Generalized Isar history, with support for linear undo, direct state
  3299 addressing etc.
  3300 
  3301 * Changed defaults for unify configuration options:
  3302 
  3303   unify_trace_bound = 50 (formerly 25)
  3304   unify_search_bound = 60 (formerly 30)
  3305 
  3306 * Different bookkeeping for code equations (INCOMPATIBILITY):
  3307 
  3308   a) On theory merge, the last set of code equations for a particular
  3309      constant is taken (in accordance with the policy applied by other
  3310      parts of the code generator framework).
  3311 
  3312   b) Code equations stemming from explicit declarations (e.g. code
  3313      attribute) gain priority over default code equations stemming
  3314      from definition, primrec, fun etc.
  3315 
  3316 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  3317 
  3318 * Unified theorem tables for both code generators.  Thus [code
  3319 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  3320 
  3321 * Command 'find_consts' searches for constants based on type and name
  3322 patterns, e.g.
  3323 
  3324     find_consts "_ => bool"
  3325 
  3326 By default, matching is against subtypes, but it may be restricted to
  3327 the whole type.  Searching by name is possible.  Multiple queries are
  3328 conjunctive and queries may be negated by prefixing them with a
  3329 hyphen:
  3330 
  3331     find_consts strict: "_ => bool" name: "Int" -"int => int"
  3332 
  3333 * New 'find_theorems' criterion "solves" matches theorems that
  3334 directly solve the current goal (modulo higher-order unification).
  3335 
  3336 * Auto solve feature for main theorem statements: whenever a new goal
  3337 is stated, "find_theorems solves" is called; any theorems that could
  3338 solve the lemma directly are listed as part of the goal state.
  3339 Cf. associated options in Proof General Isabelle settings menu,
  3340 enabled by default, with reasonable timeout for pathological cases of
  3341 higher-order unification.
  3342 
  3343 
  3344 *** Document preparation ***
  3345 
  3346 * Antiquotation @{lemma} now imitates a regular terminal proof,
  3347 demanding keyword 'by' and supporting the full method expression
  3348 syntax just like the Isar command 'by'.
  3349 
  3350 
  3351 *** HOL ***
  3352 
  3353 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  3354 points Main and Complex_Main remain as before.
  3355 
  3356 * Logic image HOL-Plain provides a minimal HOL with the most important
  3357 tools available (inductive, datatype, primrec, ...).  This facilitates
  3358 experimentation and tool development.  Note that user applications
  3359 (and library theories) should never refer to anything below theory
  3360 Main, as before.
  3361 
  3362 * Logic image HOL-Main stops at theory Main, and thus facilitates
  3363 experimentation due to shorter build times.
  3364 
  3365 * Logic image HOL-NSA contains theories of nonstandard analysis which
  3366 were previously part of former HOL-Complex.  Entry point Hyperreal
  3367 remains valid, but theories formerly using Complex_Main should now use
  3368 new entry point Hypercomplex.
  3369 
  3370 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  3371 Posix processes.  Avoids potentially expensive forking of the ML
  3372 process.  New thread-based implementation also works on non-Unix
  3373 platforms (Cygwin).  Provers are no longer hardwired, but defined
  3374 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  3375 commands are covered in the isar-ref manual.
  3376 
  3377 * Wrapper scripts for remote SystemOnTPTP service allows to use
  3378 sledgehammer without local ATP installation (Vampire etc.). Other
  3379 provers may be included via suitable ML wrappers, see also
  3380 src/HOL/ATP_Linkup.thy.
  3381 
  3382 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  3383 menu.
  3384 
  3385 * The metis method no longer fails because the theorem is too trivial
  3386 (contains the empty clause).
  3387 
  3388 * The metis method now fails in the usual manner, rather than raising
  3389 an exception, if it determines that it cannot prove the theorem.
  3390 
  3391 * Method "coherent" implements a prover for coherent logic (see also
  3392 src/Tools/coherent.ML).
  3393 
  3394 * Constants "undefined" and "default" replace "arbitrary".  Usually
  3395 "undefined" is the right choice to replace "arbitrary", though
  3396 logically there is no difference.  INCOMPATIBILITY.
  3397 
  3398 * Command "value" now integrates different evaluation mechanisms.  The
  3399 result of the first successful evaluation mechanism is printed.  In
  3400 square brackets a particular named evaluation mechanisms may be
  3401 specified (currently, [SML], [code] or [nbe]).  See further
  3402 src/HOL/ex/Eval_Examples.thy.
  3403 
  3404 * Normalization by evaluation now allows non-leftlinear equations.
  3405 Declare with attribute [code nbe].
  3406 
  3407 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  3408 as the structured Isar versions "cases" and "induct", cf. the
  3409 corresponding "cases" and "induct" attributes.  Mutual induction rules
  3410 are now presented as a list of individual projections
  3411 (e.g. foo_bar.inducts for types foo and bar); the old format with
  3412 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  3413 rare situations a different rule is selected --- notably nested tuple
  3414 elimination instead of former prod.exhaust: use explicit (case_tac t
  3415 rule: prod.exhaust) here.
  3416 
  3417 * Attributes "cases", "induct", "coinduct" support "del" option.
  3418 
  3419 * Removed fact "case_split_thm", which duplicates "case_split".
  3420 
  3421 * The option datatype has been moved to a new theory Option.  Renamed
  3422 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  3423 
  3424 * New predicate "strict_mono" classifies strict functions on partial
  3425 orders.  With strict functions on linear orders, reasoning about
  3426 (in)equalities is facilitated by theorems "strict_mono_eq",
  3427 "strict_mono_less_eq" and "strict_mono_less".
  3428 
  3429 * Some set operations are now proper qualified constants with
  3430 authentic syntax.  INCOMPATIBILITY:
  3431 
  3432     op Int ~>   Set.Int
  3433     op Un ~>    Set.Un
  3434     INTER ~>    Set.INTER
  3435     UNION ~>    Set.UNION
  3436     Inter ~>    Set.Inter
  3437     Union ~>    Set.Union
  3438     {} ~>       Set.empty
  3439     UNIV ~>     Set.UNIV
  3440 
  3441 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  3442 theory Set.
  3443 
  3444 * Auxiliary class "itself" has disappeared -- classes without any
  3445 parameter are treated as expected by the 'class' command.
  3446 
  3447 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  3448 
  3449 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  3450 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  3451 
  3452 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  3453 method "approximation".  It proves formulas on real values by using
  3454 interval arithmetic.  In the formulas are also the transcendental
  3455 functions sin, cos, tan, atan, ln, exp and the constant pi are
  3456 allowed. For examples see
  3457 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  3458 
  3459 * Theory "Reflection" now resides in HOL/Library.
  3460 
  3461 * Entry point to Word library now simply named "Word".
  3462 INCOMPATIBILITY.
  3463 
  3464 * Made source layout more coherent with logical distribution
  3465 structure:
  3466 
  3467     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  3468     src/HOL/Library/Code_Message.thy ~> src/HOL/
  3469     src/HOL/Library/GCD.thy ~> src/HOL/
  3470     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  3471     src/HOL/Library/Parity.thy ~> src/HOL/
  3472     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  3473     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  3474     src/HOL/Real/Lubs.thy ~> src/HOL/
  3475     src/HOL/Real/PReal.thy ~> src/HOL/
  3476     src/HOL/Real/Rational.thy ~> src/HOL/
  3477     src/HOL/Real/RComplete.thy ~> src/HOL/
  3478     src/HOL/Real/RealDef.thy ~> src/HOL/
  3479     src/HOL/Real/RealPow.thy ~> src/HOL/
  3480     src/HOL/Real/Real.thy ~> src/HOL/
  3481     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  3482     src/HOL/Complex/Complex.thy ~> src/HOL/
  3483     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  3484     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  3485     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  3486     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  3487     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  3488     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  3489     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  3490     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  3491     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  3492     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  3493     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  3494     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  3495     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  3496     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  3497     src/HOL/Real/Float ~> src/HOL/Library/
  3498     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  3499     src/HOL/Real/RealVector.thy ~> src/HOL/
  3500 
  3501     src/HOL/arith_data.ML ~> src/HOL/Tools
  3502     src/HOL/hologic.ML ~> src/HOL/Tools
  3503     src/HOL/simpdata.ML ~> src/HOL/Tools
  3504     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3505     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3506     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3507     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3508     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3509     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3510     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3511 
  3512     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3513     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3514     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3515     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3516     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3517     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3518 
  3519 * If methods "eval" and "evaluation" encounter a structured proof
  3520 state with !!/==>, only the conclusion is evaluated to True (if
  3521 possible), avoiding strange error messages.
  3522 
  3523 * Method "sizechange" automates termination proofs using (a
  3524 modification of) the size-change principle.  Requires SAT solver.  See
  3525 src/HOL/ex/Termination.thy for examples.
  3526 
  3527 * Simplifier: simproc for let expressions now unfolds if bound
  3528 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3529 
  3530 * Method "arith": Linear arithmetic now ignores all inequalities when
  3531 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3532 
  3533 * New attribute "arith" for facts that should always be used
  3534 automatically by arithmetic. It is intended to be used locally in
  3535 proofs, e.g.
  3536 
  3537   assumes [arith]: "x > 0"
  3538 
  3539 Global usage is discouraged because of possible performance impact.
  3540 
  3541 * New classes "top" and "bot" with corresponding operations "top" and
  3542 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3543 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3544 
  3545 * Changed definition lemma "less_fun_def" in order to provide an
  3546 instance for preorders on functions; use lemma "less_le" instead.
  3547 INCOMPATIBILITY.
  3548 
  3549 * Theory Orderings: class "wellorder" moved here, with explicit
  3550 induction rule "less_induct" as assumption.  For instantiation of
  3551 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3552 INCOMPATIBILITY.
  3553 
  3554 * Theory Orderings: added class "preorder" as superclass of "order".
  3555 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3556 etc. slightly changed.  Some theorems named order_class.* now named
  3557 preorder_class.*.
  3558 
  3559 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3560 "diag" to "Id_on".
  3561 
  3562 * Theory Finite_Set: added a new fold combinator of type
  3563 
  3564   ('a => 'b => 'b) => 'b => 'a set => 'b
  3565 
  3566 Occasionally this is more convenient than the old fold combinator
  3567 which is now defined in terms of the new one and renamed to
  3568 fold_image.
  3569 
  3570 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3571 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3572 extended with further lemmas!).  At the moment both still exist but
  3573 the former will disappear at some point.
  3574 
  3575 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3576 class recpower.  Type-specific simp rules for various recpower types
  3577 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3578 
  3579 rat_power_0    -> power_0
  3580 rat_power_Suc  -> power_Suc
  3581 realpow_0      -> power_0
  3582 realpow_Suc    -> power_Suc
  3583 complexpow_0   -> power_0
  3584 complexpow_Suc -> power_Suc
  3585 power_poly_0   -> power_0
  3586 power_poly_Suc -> power_Suc
  3587 
  3588 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3589 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3590 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3591 of lemmas from Divides has been generalized from nat to class
  3592 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3593 renames resulting from duplicate elimination:
  3594 
  3595     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3596     zero_dvd_iff ~>         dvd_0_left_iff
  3597     dvd_0 ~>                dvd_0_right
  3598     DIVISION_BY_ZERO_DIV ~> div_by_0
  3599     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3600     mult_div ~>             div_mult_self2_is_id
  3601     mult_mod ~>             mod_mult_self2_is_0
  3602 
  3603 * Theory IntDiv: removed many lemmas that are instances of class-based
  3604 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3605 rename old lemmas as follows:
  3606 
  3607 dvd_diff               -> nat_dvd_diff
  3608 dvd_zminus_iff         -> dvd_minus_iff
  3609 mod_add1_eq            -> mod_add_eq
  3610 mod_mult1_eq           -> mod_mult_right_eq
  3611 mod_mult1_eq'          -> mod_mult_left_eq
  3612 mod_mult_distrib_mod   -> mod_mult_eq
  3613 nat_mod_add_left_eq    -> mod_add_left_eq
  3614 nat_mod_add_right_eq   -> mod_add_right_eq
  3615 nat_mod_div_trivial    -> mod_div_trivial
  3616 nat_mod_mod_trivial    -> mod_mod_trivial
  3617 zdiv_zadd_self1        -> div_add_self1
  3618 zdiv_zadd_self2        -> div_add_self2
  3619 zdiv_zmult_self1       -> div_mult_self2_is_id
  3620 zdiv_zmult_self2       -> div_mult_self1_is_id
  3621 zdvd_triv_left         -> dvd_triv_left
  3622 zdvd_triv_right        -> dvd_triv_right
  3623 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3624 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3625 zmod_zadd_left_eq      -> mod_add_left_eq
  3626 zmod_zadd_right_eq     -> mod_add_right_eq
  3627 zmod_zadd_self1        -> mod_add_self1
  3628 zmod_zadd_self2        -> mod_add_self2
  3629 zmod_zadd1_eq          -> mod_add_eq
  3630 zmod_zdiff1_eq         -> mod_diff_eq
  3631 zmod_zdvd_zmod         -> mod_mod_cancel
  3632 zmod_zmod_cancel       -> mod_mod_cancel
  3633 zmod_zmult_self1       -> mod_mult_self2_is_0
  3634 zmod_zmult_self2       -> mod_mult_self1_is_0
  3635 zmod_1                 -> mod_by_1
  3636 zdiv_1                 -> div_by_1
  3637 zdvd_abs1              -> abs_dvd_iff
  3638 zdvd_abs2              -> dvd_abs_iff
  3639 zdvd_refl              -> dvd_refl
  3640 zdvd_trans             -> dvd_trans
  3641 zdvd_zadd              -> dvd_add
  3642 zdvd_zdiff             -> dvd_diff
  3643 zdvd_zminus_iff        -> dvd_minus_iff
  3644 zdvd_zminus2_iff       -> minus_dvd_iff
  3645 zdvd_zmultD            -> dvd_mult_right
  3646 zdvd_zmultD2           -> dvd_mult_left
  3647 zdvd_zmult_mono        -> mult_dvd_mono
  3648 zdvd_0_right           -> dvd_0_right
  3649 zdvd_0_left            -> dvd_0_left_iff
  3650 zdvd_1_left            -> one_dvd
  3651 zminus_dvd_iff         -> minus_dvd_iff
  3652 
  3653 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3654 
  3655 * The real numbers offer decimal input syntax: 12.34 is translated
  3656 into 1234/10^2. This translation is not reversed upon output.
  3657 
  3658 * Theory Library/Polynomial defines an abstract type 'a poly of
  3659 univariate polynomials with coefficients of type 'a.  In addition to
  3660 the standard ring operations, it also supports div and mod.  Code
  3661 generation is also supported, using list-style constructors.
  3662 
  3663 * Theory Library/Inner_Product defines a class of real_inner for real
  3664 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3665 => real.  Class real_inner is a subclass of real_normed_vector from
  3666 theory RealVector.
  3667 
  3668 * Theory Library/Product_Vector provides instances for the product
  3669 type 'a * 'b of several classes from RealVector and Inner_Product.
  3670 Definitions of addition, subtraction, scalar multiplication, norms,
  3671 and inner products are included.
  3672 
  3673 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3674 addition to the field operations, numerals and case syntax are also
  3675 supported.
  3676 
  3677 * Theory Library/Diagonalize provides constructive version of Cantor's
  3678 first diagonalization argument.
  3679 
  3680 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3681 zlcm (for int); carried together from various gcd/lcm developements in
  3682 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3683 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3684 may recover tupled syntax as follows:
  3685 
  3686     hide (open) const gcd
  3687     abbreviation gcd where
  3688       "gcd == (%(a, b). GCD.gcd a b)"
  3689     notation (output)
  3690       GCD.gcd ("gcd '(_, _')")
  3691 
  3692 The same works for lcm, zgcd, zlcm.
  3693 
  3694 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3695 instantiations for algebraic structures.  Removed some duplicate
  3696 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3697 
  3698 * ML antiquotation @{code} takes a constant as argument and generates
  3699 corresponding code in background and inserts name of the corresponding
  3700 resulting ML value/function/datatype constructor binding in place.
  3701 All occurrences of @{code} with a single ML block are generated
  3702 simultaneously.  Provides a generic and safe interface for
  3703 instrumentalizing code generation.  See
  3704 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3705 In future you ought to refrain from ad-hoc compiling generated SML
  3706 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3707 cannot refer to constants for which user-defined serializations are
  3708 set.  Refer to the corresponding ML counterpart directly in that
  3709 cases.
  3710 
  3711 * Command 'rep_datatype': instead of theorem names the command now
  3712 takes a list of terms denoting the constructors of the type to be
  3713 represented as datatype.  The characteristic theorems have to be
  3714 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3715 have disappeared in favour of existing ones:
  3716 
  3717     unit_induct                 ~> unit.induct
  3718     prod_induct                 ~> prod.induct
  3719     sum_induct                  ~> sum.induct
  3720     Suc_Suc_eq                  ~> nat.inject
  3721     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3722 
  3723 
  3724 *** HOL-Algebra ***
  3725 
  3726 * New locales for orders and lattices where the equivalence relation
  3727 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3728 locales use a record structure with field eq for the equivalence.
  3729 
  3730 * New theory of factorial domains.
  3731 
  3732 * Units_l_inv and Units_r_inv are now simp rules by default.
  3733 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3734 and/or r_inv will now also require deletion of these lemmas.
  3735 
  3736 * Renamed the following theorems, INCOMPATIBILITY:
  3737 
  3738 UpperD ~> Upper_memD
  3739 LowerD ~> Lower_memD
  3740 least_carrier ~> least_closed
  3741 greatest_carrier ~> greatest_closed
  3742 greatest_Lower_above ~> greatest_Lower_below
  3743 one_zero ~> carrier_one_zero
  3744 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3745 
  3746 
  3747 *** HOL-Nominal ***
  3748 
  3749 * Nominal datatypes can now contain type-variables.
  3750 
  3751 * Commands 'nominal_inductive' and 'equivariance' work with local
  3752 theory targets.
  3753 
  3754 * Nominal primrec can now works with local theory targets and its
  3755 specification syntax now conforms to the general format as seen in
  3756 'inductive' etc.
  3757 
  3758 * Method "perm_simp" honours the standard simplifier attributes
  3759 (no_asm), (no_asm_use) etc.
  3760 
  3761 * The new predicate #* is defined like freshness, except that on the
  3762 left hand side can be a set or list of atoms.
  3763 
  3764 * Experimental command 'nominal_inductive2' derives strong induction
  3765 principles for inductive definitions.  In contrast to
  3766 'nominal_inductive', which can only deal with a fixed number of
  3767 binders, it can deal with arbitrary expressions standing for sets of
  3768 atoms to be avoided.  The only inductive definition we have at the
  3769 moment that needs this generalisation is the typing rule for Lets in
  3770 the algorithm W:
  3771 
  3772  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3773  -----------------------------------------------------------------
  3774          Gamma |- Let x be t1 in t2 : T2
  3775 
  3776 In this rule one wants to avoid all the binders that are introduced by
  3777 "close Gamma T1".  We are looking for other examples where this
  3778 feature might be useful.  Please let us know.
  3779 
  3780 
  3781 *** HOLCF ***
  3782 
  3783 * Reimplemented the simplification procedure for proving continuity
  3784 subgoals.  The new simproc is extensible; users can declare additional
  3785 continuity introduction rules with the attribute [cont2cont].
  3786 
  3787 * The continuity simproc now uses a different introduction rule for
  3788 solving continuity subgoals on terms with lambda abstractions.  In
  3789 some rare cases the new simproc may fail to solve subgoals that the
  3790 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3791 Potential INCOMPATIBILITY.
  3792 
  3793 * Command 'fixrec': specification syntax now conforms to the general
  3794 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3795 examples.  INCOMPATIBILITY.
  3796 
  3797 
  3798 *** ZF ***
  3799 
  3800 * Proof of Zorn's Lemma for partial orders.
  3801 
  3802 
  3803 *** ML ***
  3804 
  3805 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3806 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3807 depends on multithreading, so timouts will not work before Poly/ML
  3808 5.2.1!
  3809 
  3810 * High-level support for concurrent ML programming, see
  3811 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3812 particularly convenient to organize independent functional
  3813 computations.  The concept of "synchronized variables" provides a
  3814 higher-order interface for components with shared state, avoiding the
  3815 delicate details of mutexes and condition variables.  (Requires
  3816 Poly/ML 5.2.1 or later.)
  3817 
  3818 * ML bindings produced via Isar commands are stored within the Isar
  3819 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3820 become thread-safe and work with undo as expected (concerning
  3821 top-level bindings, not side-effects on global references).
  3822 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3823 compiler at runtime; really global bindings need to be given outside a
  3824 theory.  (Requires Poly/ML 5.2 or later.)
  3825 
  3826 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3827 context.  Top-level ML bindings are stored within the proof context in
  3828 a purely sequential fashion, disregarding the nested proof structure.
  3829 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3830 proof.  (Requires Poly/ML 5.2 or later.)
  3831 
  3832 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3833 and Method.setup, as well as Isar commands 'attribute_setup' and
  3834 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3835 existing code accordingly, or use plain 'setup' together with old
  3836 Method.add_method.
  3837 
  3838 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3839 to 'a -> thm, while results are always tagged with an authentic oracle
  3840 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3841 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3842 accordingly.  Note that extra performance may be gained by producing
  3843 the cterm carefully, avoiding slow Thm.cterm_of.
  3844 
  3845 * Simplified interface for defining document antiquotations via
  3846 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3847 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3848 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3849 examples.
  3850 
  3851 * More systematic treatment of long names, abstract name bindings, and
  3852 name space operations.  Basic operations on qualified names have been
  3853 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3854 Long_Name.append.  Old type bstring has been mostly replaced by
  3855 abstract type binding (see structure Binding), which supports precise
  3856 qualification by packages and local theory targets, as well as proper
  3857 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3858 bstring values into Binding.name, or better pass through abstract
  3859 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3860 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3861 
  3862 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3863 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3864 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3865 
  3866 * Disposed old type and term read functions (Sign.read_def_typ,
  3867 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3868 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3869 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3870 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3871 resort for legacy applications.
  3872 
  3873 * Disposed old declarations, tactics, tactic combinators that refer to
  3874 the simpset or claset of an implicit theory (such as Addsimps,
  3875 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3876 embedded ML text, or local_simpset_of with a proper context passed as
  3877 explicit runtime argument.
  3878 
  3879 * Rules and tactics that read instantiations (read_instantiate,
  3880 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3881 context, which is required for parsing and type-checking.  Moreover,
  3882 the variables are specified as plain indexnames, not string encodings
  3883 thereof.  INCOMPATIBILITY.
  3884 
  3885 * Generic Toplevel.add_hook interface allows to analyze the result of
  3886 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3887 for theorem dependency output of transactions resulting in a new
  3888 theory state.
  3889 
  3890 * ML antiquotations: block-structured compilation context indicated by
  3891 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3892 
  3893   @{binding name}                         - basic name binding
  3894   @{let ?pat = term}                      - term abbreviation (HO matching)
  3895   @{note name = fact}                     - fact abbreviation
  3896   @{thm fact}                             - singleton fact (with attributes)
  3897   @{thms fact}                            - general fact (with attributes)
  3898   @{lemma prop by method}                 - singleton goal
  3899   @{lemma prop by meth1 meth2}            - singleton goal
  3900   @{lemma prop1 ... propN by method}      - general goal
  3901   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3902   @{lemma (open) ...}                     - open derivation
  3903 
  3904 
  3905 *** System ***
  3906 
  3907 * The Isabelle "emacs" tool provides a specific interface to invoke
  3908 Proof General / Emacs, with more explicit failure if that is not
  3909 installed (the old isabelle-interface script silently falls back on
  3910 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3911 installation location of the Proof General distribution.
  3912 
  3913 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3914 the Isabelle process into a JVM/Scala application.  See
  3915 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3916 process wrapper has been discontinued.)
  3917 
  3918 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3919 
  3920 * Various status messages (with exact source position information) are
  3921 emitted, if proper markup print mode is enabled.  This allows
  3922 user-interface components to provide detailed feedback on internal
  3923 prover operations.
  3924 
  3925 
  3926 
  3927 New in Isabelle2008 (June 2008)
  3928 -------------------------------
  3929 
  3930 *** General ***
  3931 
  3932 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3933 and updated, with formally checked references as hyperlinks.
  3934 
  3935 * Theory loader: use_thy (and similar operations) no longer set the
  3936 implicit ML context, which was occasionally hard to predict and in
  3937 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3938 provides a proper context already.
  3939 
  3940 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3941 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3942 'use' within a theory file will do the job.
  3943 
  3944 * Name space merge now observes canonical order, i.e. the second space
  3945 is inserted into the first one, while existing entries in the first
  3946 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3947 swap theory imports.
  3948 
  3949 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3950 INCOMPATIBILITY in identifier syntax etc.
  3951 
  3952 * Outer syntax: string tokens no longer admit escaped white space,
  3953 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3954 white space without escapes.
  3955 
  3956 * Outer syntax: string tokens may contain arbitrary character codes
  3957 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3958 "foo_bar".
  3959 
  3960 
  3961 *** Pure ***
  3962 
  3963 * Context-dependent token translations.  Default setup reverts locally
  3964 fixed variables, and adds hilite markup for undeclared frees.
  3965 
  3966 * Unused theorems can be found using the new command 'unused_thms'.
  3967 There are three ways of invoking it:
  3968 
  3969 (1) unused_thms
  3970      Only finds unused theorems in the current theory.
  3971 
  3972 (2) unused_thms thy_1 ... thy_n -
  3973      Finds unused theorems in the current theory and all of its ancestors,
  3974      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3975 
  3976 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3977      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3978      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3979      their ancestors.
  3980 
  3981 In order to increase the readability of the list produced by
  3982 unused_thms, theorems that have been created by a particular instance
  3983 of a theory command such as 'inductive' or 'function' are considered
  3984 to belong to the same "group", meaning that if at least one theorem in
  3985 this group is used, the other theorems in the same group are no longer
  3986 reported as unused.  Moreover, if all theorems in the group are
  3987 unused, only one theorem in the group is displayed.
  3988 
  3989 Note that proof objects have to be switched on in order for
  3990 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3991 usually the case when using Proof General with the default settings).
  3992 
  3993 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3994 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3995 duplicate fact bindings, or even accidental fact duplications.  Note
  3996 that tools may maintain dynamically scoped facts systematically, using
  3997 PureThy.add_thms_dynamic.
  3998 
  3999 * Command 'hide' now allows to hide from "fact" name space as well.
  4000 
  4001 * Eliminated destructive theorem database, simpset, claset, and
  4002 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  4003 update of theories within ML code.
  4004 
  4005 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  4006 INCOMPATIBILITY, object-logics depending on former Pure require
  4007 additional setup PureThy.old_appl_syntax_setup; object-logics
  4008 depending on former CPure need to refer to Pure.
  4009 
  4010 * Commands 'use' and 'ML' are now purely functional, operating on
  4011 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  4012 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  4013 INCOMPATIBILITY.
  4014 
  4015 * Command 'setup': discontinued implicit version with ML reference.
  4016 
  4017 * Instantiation target allows for simultaneous specification of class
  4018 instance operations together with an instantiation proof.
  4019 Type-checking phase allows to refer to class operations uniformly.
  4020 See src/HOL/Complex/Complex.thy for an Isar example and
  4021 src/HOL/Library/Eval.thy for an ML example.
  4022 
  4023 * Indexing of literal facts: be more serious about including only
  4024 facts from the visible specification/proof context, but not the
  4025 background context (locale etc.).  Affects `prop` notation and method
  4026 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  4027 situations.
  4028 
  4029 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  4030 "(open)" option, which used to expose internal bound variables to the
  4031 proof text.
  4032 
  4033 * Isar statements: removed obsolete case "rule_context".
  4034 INCOMPATIBILITY, better use explicit fixes/assumes.
  4035 
  4036 * Locale proofs: default proof step now includes 'unfold_locales';
  4037 hence 'proof' without argument may be used to unfold locale
  4038 predicates.
  4039 
  4040 
  4041 *** Document preparation ***
  4042 
  4043 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  4044 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  4045 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  4046 spot); renamed link color from "darkblue" to "linkcolor" (default
  4047 value unchanged, can be redefined via \definecolor); no longer sets
  4048 "a4paper" option (unnecessary or even intrusive).
  4049 
  4050 * Antiquotation @{lemma A method} proves proposition A by the given
  4051 method (either a method name or a method name plus (optional) method
  4052 arguments in parentheses) and prints A just like @{prop A}.
  4053 
  4054 
  4055 *** HOL ***
  4056 
  4057 * New primrec package.  Specification syntax conforms in style to
  4058 definition/function/....  No separate induction rule is provided.  The
  4059 "primrec" command distinguishes old-style and new-style specifications
  4060 by syntax.  The former primrec package is now named OldPrimrecPackage.
  4061 When adjusting theories, beware: constants stemming from new-style
  4062 primrec specifications have authentic syntax.
  4063 
  4064 * Metis prover is now an order of magnitude faster, and also works
  4065 with multithreading.
  4066 
  4067 * Metis: the maximum number of clauses that can be produced from a
  4068 theorem is now given by the attribute max_clauses.  Theorems that
  4069 exceed this number are ignored, with a warning printed.
  4070 
  4071 * Sledgehammer no longer produces structured proofs by default. To
  4072 enable, declare [[sledgehammer_full = true]].  Attributes
  4073 reconstruction_modulus, reconstruction_sorts renamed
  4074 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  4075 
  4076 * Method "induct_scheme" derives user-specified induction rules
  4077 from well-founded induction and completeness of patterns. This factors
  4078 out some operations that are done internally by the function package
  4079 and makes them available separately.  See
  4080 src/HOL/ex/Induction_Scheme.thy for examples.
  4081 
  4082 * More flexible generation of measure functions for termination
  4083 proofs: Measure functions can be declared by proving a rule of the
  4084 form "is_measure f" and giving it the [measure_function] attribute.
  4085 The "is_measure" predicate is logically meaningless (always true), and
  4086 just guides the heuristic.  To find suitable measure functions, the
  4087 termination prover sets up the goal "is_measure ?f" of the appropriate
  4088 type and generates all solutions by prolog-style backwards proof using
  4089 the declared rules.
  4090 
  4091 This setup also deals with rules like 
  4092 
  4093   "is_measure f ==> is_measure (list_size f)"
  4094 
  4095 which accommodates nested datatypes that recurse through lists.
  4096 Similar rules are predeclared for products and option types.
  4097 
  4098 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  4099 
  4100   INCOMPATIBILITIES:
  4101 
  4102   - Definitions of overloaded constants on sets have to be replaced by
  4103     definitions on => and bool.
  4104 
  4105   - Some definitions of overloaded operators on sets can now be proved
  4106     using the definitions of the operators on => and bool.  Therefore,
  4107     the following theorems have been renamed:
  4108 
  4109       subset_def   -> subset_eq
  4110       psubset_def  -> psubset_eq
  4111       set_diff_def -> set_diff_eq
  4112       Compl_def    -> Compl_eq
  4113       Sup_set_def  -> Sup_set_eq
  4114       Inf_set_def  -> Inf_set_eq
  4115       sup_set_def  -> sup_set_eq
  4116       inf_set_def  -> inf_set_eq
  4117 
  4118   - Due to the incompleteness of the HO unification algorithm, some
  4119     rules such as subst may require manual instantiation, if some of
  4120     the unknowns in the rule is a set.
  4121 
  4122   - Higher order unification and forward proofs:
  4123     The proof pattern
  4124 
  4125       have "P (S::'a set)" <...>
  4126       then have "EX S. P S" ..
  4127 
  4128     no longer works (due to the incompleteness of the HO unification
  4129     algorithm) and must be replaced by the pattern
  4130 
  4131       have "EX S. P S"
  4132       proof
  4133         show "P S" <...>
  4134       qed
  4135 
  4136   - Calculational reasoning with subst (or similar rules):
  4137     The proof pattern
  4138 
  4139       have "P (S::'a set)" <...>
  4140       also have "S = T" <...>
  4141       finally have "P T" .
  4142 
  4143     no longer works (for similar reasons as the previous example) and
  4144     must be replaced by something like
  4145 
  4146       have "P (S::'a set)" <...>
  4147       moreover have "S = T" <...>
  4148       ultimately have "P T" by simp
  4149 
  4150   - Tactics or packages written in ML code:
  4151     Code performing pattern matching on types via
  4152 
  4153       Type ("set", [T]) => ...
  4154 
  4155     must be rewritten. Moreover, functions like strip_type or
  4156     binder_types no longer return the right value when applied to a
  4157     type of the form
  4158 
  4159       T1 => ... => Tn => U => bool
  4160 
  4161     rather than
  4162 
  4163       T1 => ... => Tn => U set
  4164 
  4165 * Merged theories Wellfounded_Recursion, Accessible_Part and
  4166 Wellfounded_Relations to theory Wellfounded.
  4167 
  4168 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  4169 
  4170 * Class finite no longer treats UNIV as class parameter.  Use class
  4171 enum from theory Library/Enum instead to achieve a similar effect.
  4172 INCOMPATIBILITY.
  4173 
  4174 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  4175 and "Cons".  INCOMPATIBILITY.
  4176 
  4177 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  4178 Potential INCOMPATIBILITY.
  4179 
  4180 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  4181 injective_fst_snd removed, use split_eta and prod_eqI instead.
  4182 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  4183 
  4184 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  4185 the same name in theory Orderings:
  4186 
  4187   less_trans
  4188   less_linear
  4189   le_imp_less_or_eq
  4190   le_less_trans
  4191   less_le_trans
  4192   less_not_sym
  4193   less_asym
  4194 
  4195 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  4196 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  4197 and different variable names.
  4198 
  4199 * Library/Option_ord.thy: Canonical order on option type.
  4200 
  4201 * Library/RBT.thy: Red-black trees, an efficient implementation of
  4202 finite maps.
  4203 
  4204 * Library/Countable.thy: Type class for countable types.
  4205 
  4206 * Theory Int: The representation of numerals has changed.  The infix
  4207 operator BIT and the bit datatype with constructors B0 and B1 have
  4208 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  4209 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  4210 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  4211 accordingly.
  4212 
  4213 * Theory Nat: definition of <= and < on natural numbers no longer
  4214 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  4215 le_def and less_def have disappeared.  Consider lemmas not_less
  4216 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  4217 
  4218 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  4219 (whose purpose mainly is for various fold_set functionals) have been
  4220 abandoned in favor of the existing algebraic classes
  4221 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  4222 lower_semilattice (resp. upper_semilattice) and linorder.
  4223 INCOMPATIBILITY.
  4224 
  4225 * Theory Transitive_Closure: induct and cases rules now declare proper
  4226 case_names ("base" and "step").  INCOMPATIBILITY.
  4227 
  4228 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  4229 lattices.  The form set-specific version is available as
  4230 Inductive.lfp_ordinal_induct_set.
  4231 
  4232 * Renamed theorems "power.simps" to "power_int.simps".
  4233 INCOMPATIBILITY.
  4234 
  4235 * Class semiring_div provides basic abstract properties of semirings
  4236 with division and modulo operations.  Subsumes former class dvd_mod.
  4237 
  4238 * Merged theories IntDef, Numeral and IntArith into unified theory
  4239 Int.  INCOMPATIBILITY.
  4240 
  4241 * Theory Library/Code_Index: type "index" now represents natural
  4242 numbers rather than integers.  INCOMPATIBILITY.
  4243 
  4244 * New class "uminus" with operation "uminus" (split of from class
  4245 "minus" which now only has operation "minus", binary).
  4246 INCOMPATIBILITY.
  4247 
  4248 * Constants "card", "internal_split", "option_map" now with authentic
  4249 syntax.  INCOMPATIBILITY.
  4250 
  4251 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  4252 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  4253 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  4254 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  4255 Sup_set_def, le_def, less_def, option_map_def now with object
  4256 equality.  INCOMPATIBILITY.
  4257 
  4258 * Records. Removed K_record, and replaced it by pure lambda term
  4259 %x. c. The simplifier setup is now more robust against eta expansion.
  4260 INCOMPATIBILITY: in cases explicitly referring to K_record.
  4261 
  4262 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  4263 
  4264 * Library/ListVector: new theory of arithmetic vector operations.
  4265 
  4266 * Library/Order_Relation: new theory of various orderings as sets of
  4267 pairs.  Defines preorders, partial orders, linear orders and
  4268 well-orders on sets and on types.
  4269 
  4270 
  4271 *** ZF ***
  4272 
  4273 * Renamed some theories to allow to loading both ZF and HOL in the
  4274 same session:
  4275 
  4276   Datatype  -> Datatype_ZF
  4277   Inductive -> Inductive_ZF
  4278   Int       -> Int_ZF
  4279   IntDiv    -> IntDiv_ZF
  4280   Nat       -> Nat_ZF
  4281   List      -> List_ZF
  4282   Main      -> Main_ZF
  4283 
  4284 INCOMPATIBILITY: ZF theories that import individual theories below
  4285 Main might need to be adapted.  Regular theory Main is still
  4286 available, as trivial extension of Main_ZF.
  4287 
  4288 
  4289 *** ML ***
  4290 
  4291 * ML within Isar: antiquotation @{const name} or @{const
  4292 name(typargs)} produces statically-checked Const term.
  4293 
  4294 * Functor NamedThmsFun: data is available to the user as dynamic fact
  4295 (of the same name).  Removed obsolete print command.
  4296 
  4297 * Removed obsolete "use_legacy_bindings" function.
  4298 
  4299 * The ``print mode'' is now a thread-local value derived from a global
  4300 template (the former print_mode reference), thus access becomes
  4301 non-critical.  The global print_mode reference is for session
  4302 management only; user-code should use print_mode_value,
  4303 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  4304 
  4305 * Functions system/system_out provide a robust way to invoke external
  4306 shell commands, with propagation of interrupts (requires Poly/ML
  4307 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  4308 
  4309 
  4310 *** System ***
  4311 
  4312 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  4313 in accordance with Proof General 3.7, which prefers GNU emacs.
  4314 
  4315 * isatool tty runs Isabelle process with plain tty interaction;
  4316 optional line editor may be specified via ISABELLE_LINE_EDITOR
  4317 setting, the default settings attempt to locate "ledit" and "rlwrap".
  4318 
  4319 * isatool browser now works with Cygwin as well, using general
  4320 "javapath" function defined in Isabelle process environment.
  4321 
  4322 * YXML notation provides a simple and efficient alternative to
  4323 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  4324 isatool yxml as described in the Isabelle system manual.
  4325 
  4326 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  4327 provides general wrapper for managing an Isabelle process in a robust
  4328 fashion, with ``cooked'' output from stdin/stderr.
  4329 
  4330 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  4331 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  4332 
  4333 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  4334 way of changing the user's settings is via
  4335 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  4336 script.
  4337 
  4338 * Multithreading.max_threads := 0 refers to the number of actual CPU
  4339 cores of the underlying machine, which is a good starting point for
  4340 optimal performance tuning.  The corresponding usedir option -M allows
  4341 "max" as an alias for "0".  WARNING: does not work on certain versions
  4342 of Mac OS (with Poly/ML 5.1).
  4343 
  4344 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  4345 adverse effect of Isabelle flooding interactive front-ends (notably
  4346 ProofGeneral / XEmacs).
  4347 
  4348 
  4349 
  4350 New in Isabelle2007 (November 2007)
  4351 -----------------------------------
  4352 
  4353 *** General ***
  4354 
  4355 * More uniform information about legacy features, notably a
  4356 warning/error of "Legacy feature: ...", depending on the state of the
  4357 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  4358 legacy features will disappear eventually.
  4359 
  4360 * Theory syntax: the header format ``theory A = B + C:'' has been
  4361 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  4362 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  4363 
  4364 * Theory syntax: the old non-Isar theory file format has been
  4365 discontinued altogether.  Note that ML proof scripts may still be used
  4366 with Isar theories; migration is usually quite simple with the ML
  4367 function use_legacy_bindings.  INCOMPATIBILITY.
  4368 
  4369 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  4370 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  4371 quotes.
  4372 
  4373 * Theory loader: be more serious about observing the static theory
  4374 header specifications (including optional directories), but not the
  4375 accidental file locations of previously successful loads.  The strict
  4376 update policy of former update_thy is now already performed by
  4377 use_thy, so the former has been removed; use_thys updates several
  4378 theories simultaneously, just as 'imports' within a theory header
  4379 specification, but without merging the results.  Potential
  4380 INCOMPATIBILITY: may need to refine theory headers and commands
  4381 ROOT.ML which depend on load order.
  4382 
  4383 * Theory loader: optional support for content-based file
  4384 identification, instead of the traditional scheme of full physical
  4385 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  4386 (cf. the system manual).  The new scheme allows to work with
  4387 non-finished theories in persistent session images, such that source
  4388 files may be moved later on without requiring reloads.
  4389 
  4390 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4391 file (with the same base name as the theory) are considered a legacy
  4392 feature, which will disappear eventually. Even now, the theory loader
  4393 no longer maintains dependencies on such files.
  4394 
  4395 * Syntax: the scope for resolving ambiguities via type-inference is
  4396 now limited to individual terms, instead of whole simultaneous
  4397 specifications as before. This greatly reduces the complexity of the
  4398 syntax module and improves flexibility by separating parsing and
  4399 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  4400 'fixes' etc.) are required in rare situations.
  4401 
  4402 * Syntax: constants introduced by new-style packages ('definition',
  4403 'abbreviation' etc.) are passed through the syntax module in
  4404 ``authentic mode''. This means that associated mixfix annotations
  4405 really stick to such constants, independently of potential name space
  4406 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  4407 trees are represented slightly differently, may need to adapt syntax
  4408 translations accordingly. Use CONST marker in 'translations' and
  4409 @{const_syntax} antiquotation in 'parse_translation' etc.
  4410 
  4411 * Legacy goal package: reduced interface to the bare minimum required
  4412 to keep existing proof scripts running.  Most other user-level
  4413 functions are now part of the OldGoals structure, which is *not* open
  4414 by default (consider isatool expandshort before open OldGoals).
  4415 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  4416 these tend to cause confusion about the actual goal (!) context being
  4417 used here, which is not necessarily the same as the_context().
  4418 
  4419 * Command 'find_theorems': supports "*" wild-card in "name:"
  4420 criterion; "with_dups" option.  Certain ProofGeneral versions might
  4421 support a specific search form (see ProofGeneral/CHANGES).
  4422 
  4423 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  4424 by default, which means that "prems" (and also "fixed variables") are
  4425 suppressed from proof state output.  Note that the ProofGeneral
  4426 settings mechanism allows to change and save options persistently, but
  4427 older versions of Isabelle will fail to start up if a negative prems
  4428 limit is imposed.
  4429 
  4430 * Local theory targets may be specified by non-nested blocks of
  4431 ``context/locale/class ... begin'' followed by ``end''.  The body may
  4432 contain definitions, theorems etc., including any derived mechanism
  4433 that has been implemented on top of these primitives.  This concept
  4434 generalizes the existing ``theorem (in ...)'' towards more versatility
  4435 and scalability.
  4436 
  4437 * Proof General interface: proper undo of final 'end' command;
  4438 discontinued Isabelle/classic mode (ML proof scripts).
  4439 
  4440 
  4441 *** Document preparation ***
  4442 
  4443 * Added antiquotation @{theory name} which prints the given name,
  4444 after checking that it refers to a valid ancestor theory in the
  4445 current context.
  4446 
  4447 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  4448 check the given source text as ML type/structure, printing verbatim.
  4449 
  4450 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  4451 "c args == rhs" given in the current context.  (Any number of
  4452 arguments may be given on the LHS.)
  4453 
  4454 
  4455 *** Pure ***
  4456 
  4457 * The 'class' package offers a combination of axclass and locale to
  4458 achieve Haskell-like type classes in Isabelle.  Definitions and
  4459 theorems within a class context produce both relative results (with
  4460 implicit parameters according to the locale context), and polymorphic
  4461 constants with qualified polymorphism (according to the class
  4462 context).  Within the body context of a 'class' target, a separate
  4463 syntax layer ("user space type system") takes care of converting
  4464 between global polymorphic consts and internal locale representation.
  4465 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  4466 "isatool doc classes" provides a tutorial.
  4467 
  4468 * Generic code generator framework allows to generate executable
  4469 code for ML and Haskell (including Isabelle classes).  A short usage
  4470 sketch:
  4471 
  4472     internal compilation:
  4473         export_code <list of constants (term syntax)> in SML
  4474     writing SML code to a file:
  4475         export_code <list of constants (term syntax)> in SML <filename>
  4476     writing OCaml code to a file:
  4477         export_code <list of constants (term syntax)> in OCaml <filename>
  4478     writing Haskell code to a bunch of files:
  4479         export_code <list of constants (term syntax)> in Haskell <filename>
  4480 
  4481     evaluating closed propositions to True/False using code generation:
  4482         method ``eval''
  4483 
  4484 Reasonable default setup of framework in HOL.
  4485 
  4486 Theorem attributs for selecting and transforming function equations theorems:
  4487 
  4488     [code fun]:        select a theorem as function equation for a specific constant
  4489     [code fun del]:    deselect a theorem as function equation for a specific constant
  4490     [code inline]:     select an equation theorem for unfolding (inlining) in place
  4491     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  4492 
  4493 User-defined serializations (target in {SML, OCaml, Haskell}):
  4494 
  4495     code_const <and-list of constants (term syntax)>
  4496       {(target) <and-list of const target syntax>}+
  4497 
  4498     code_type <and-list of type constructors>
  4499       {(target) <and-list of type target syntax>}+
  4500 
  4501     code_instance <and-list of instances>
  4502       {(target)}+
  4503         where instance ::= <type constructor> :: <class>
  4504 
  4505     code_class <and_list of classes>
  4506       {(target) <and-list of class target syntax>}+
  4507         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4508 
  4509 code_instance and code_class only are effective to target Haskell.
  4510 
  4511 For example usage see src/HOL/ex/Codegenerator.thy and
  4512 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4513 generation from Isabelle/HOL theories is available via "isatool doc
  4514 codegen".
  4515 
  4516 * Code generator: consts in 'consts_code' Isar commands are now
  4517 referred to by usual term syntax (including optional type
  4518 annotations).
  4519 
  4520 * Command 'no_translations' removes translation rules from theory
  4521 syntax.
  4522 
  4523 * Overloaded definitions are now actually checked for acyclic
  4524 dependencies.  The overloading scheme is slightly more general than
  4525 that of Haskell98, although Isabelle does not demand an exact
  4526 correspondence to type class and instance declarations.
  4527 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4528 exotic versions of overloading -- at the discretion of the user!
  4529 
  4530 Polymorphic constants are represented via type arguments, i.e. the
  4531 instantiation that matches an instance against the most general
  4532 declaration given in the signature.  For example, with the declaration
  4533 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4534 as c(nat).  Overloading is essentially simultaneous structural
  4535 recursion over such type arguments.  Incomplete specification patterns
  4536 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4537 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4538 Command 'print_theory' outputs the normalized system of recursive
  4539 equations, see section "definitions".
  4540 
  4541 * Configuration options are maintained within the theory or proof
  4542 context (with name and type bool/int/string), providing a very simple
  4543 interface to a poor-man's version of general context data.  Tools may
  4544 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4545 these values using Config.get etc.  Users may change options via an
  4546 associated attribute of the same name.  This form of context
  4547 declaration works particularly well with commands 'declare' or
  4548 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4549 very easy to avoid global references, which would not observe Isar
  4550 toplevel undo/redo and fail to work with multithreading.
  4551 
  4552 Various global ML references of Pure and HOL have been turned into
  4553 configuration options:
  4554 
  4555   Unify.search_bound		unify_search_bound
  4556   Unify.trace_bound		unify_trace_bound
  4557   Unify.trace_simp		unify_trace_simp
  4558   Unify.trace_types		unify_trace_types
  4559   Simplifier.simp_depth_limit	simp_depth_limit
  4560   Blast.depth_limit		blast_depth_limit
  4561   DatatypeProp.dtK		datatype_distinctness_limit
  4562   fast_arith_neq_limit  	fast_arith_neq_limit
  4563   fast_arith_split_limit	fast_arith_split_limit
  4564 
  4565 * Named collections of theorems may be easily installed as context
  4566 data using the functor NamedThmsFun (see also
  4567 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4568 attributes; there is also a toplevel print command.  This facility is
  4569 just a common case of general context data, which is the preferred way
  4570 for anything more complex than just a list of facts in canonical
  4571 order.
  4572 
  4573 * Isar: command 'declaration' augments a local theory by generic
  4574 declaration functions written in ML.  This enables arbitrary content
  4575 being added to the context, depending on a morphism that tells the
  4576 difference of the original declaration context wrt. the application
  4577 context encountered later on.
  4578 
  4579 * Isar: proper interfaces for simplification procedures.  Command
  4580 'simproc_setup' declares named simprocs (with match patterns, and body
  4581 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4582 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4583 
  4584 * Isar: an extra pair of brackets around attribute declarations
  4585 abbreviates a theorem reference involving an internal dummy fact,
  4586 which will be ignored later --- only the effect of the attribute on
  4587 the background context will persist.  This form of in-place
  4588 declarations is particularly useful with commands like 'declare' and
  4589 'using', for example ``have A using [[simproc a]] by simp''.
  4590 
  4591 * Isar: method "assumption" (and implicit closing of subproofs) now
  4592 takes simple non-atomic goal assumptions into account: after applying
  4593 an assumption as a rule the resulting subgoals are solved by atomic
  4594 assumption steps.  This is particularly useful to finish 'obtain'
  4595 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4596 without referring to the original premise "!!x. P x ==> thesis" in the
  4597 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4598 more permissive.
  4599 
  4600 * Isar: implicit use of prems from the Isar proof context is
  4601 considered a legacy feature.  Common applications like ``have A .''
  4602 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4603 referencing facts explicitly here improves readability and
  4604 maintainability of proof texts.
  4605 
  4606 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4607 the obtained context from the course of reasoning!  For example:
  4608 
  4609   assume "EX x y. A x & B y"   -- "any previous fact"
  4610   then guess x and y by clarify
  4611 
  4612 This technique is potentially adventurous, depending on the facts and
  4613 proof tools being involved here.
  4614 
  4615 * Isar: known facts from the proof context may be specified as literal
  4616 propositions, using ASCII back-quote syntax.  This works wherever
  4617 named facts used to be allowed so far, in proof commands, proof
  4618 methods, attributes etc.  Literal facts are retrieved from the context
  4619 according to unification of type and term parameters.  For example,
  4620 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4621 theorems in the current context, then these are valid literal facts:
  4622 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4623 
  4624 There is also a proof method "fact" which does the same composition
  4625 for explicit goal states, e.g. the following proof texts coincide with
  4626 certain special cases of literal facts:
  4627 
  4628   have "A" by fact                 ==  note `A`
  4629   have "A ==> B" by fact           ==  note `A ==> B`
  4630   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4631   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4632 
  4633 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4634 outer syntax.  Thus symbolic identifiers may be used without
  4635 additional white space in declarations like this: ``assume *: A''.
  4636 
  4637 * Isar: 'print_facts' prints all local facts of the current context,
  4638 both named and unnamed ones.
  4639 
  4640 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4641 
  4642   def x == "t" and y == "u"
  4643 
  4644 * Isar: added command 'unfolding', which is structurally similar to
  4645 'using', but affects both the goal state and facts by unfolding given
  4646 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4647 'unfolded' attribute may be replaced by first-class proof text.
  4648 
  4649 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4650 and command 'unfolding' now all support object-level equalities
  4651 (potentially conditional).  The underlying notion of rewrite rule is
  4652 analogous to the 'rule_format' attribute, but *not* that of the
  4653 Simplifier (which is usually more generous).
  4654 
  4655 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4656 premises of a theorem by n. Useful in conjunction with drule.
  4657 
  4658 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4659 method expression within a sandbox consisting of the first N
  4660 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4661 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4662 simplifies all new goals that emerge from applying rule foo to the
  4663 originally first one.
  4664 
  4665 * Isar: schematic goals are no longer restricted to higher-order
  4666 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4667 expected.
  4668 
  4669 * Isar: the conclusion of a long theorem statement is now either
  4670 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4671 (essentially a disjunction of cases with local parameters and
  4672 assumptions).  The latter allows to express general elimination rules
  4673 adequately; in this notation common elimination rules look like this:
  4674 
  4675   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4676     assumes "EX x. P x"
  4677     obtains x where "P x"
  4678 
  4679   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4680     assumes "A & B"
  4681     obtains A and B
  4682 
  4683   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4684     assumes "A | B"
  4685     obtains
  4686       A
  4687     | B
  4688 
  4689 The subsequent classical rules even refer to the formal "thesis"
  4690 explicitly:
  4691 
  4692   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4693     obtains "~ thesis"
  4694 
  4695   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4696     obtains "thesis ==> something"
  4697 
  4698 The actual proof of an 'obtains' statement is analogous to that of the
  4699 Isar proof element 'obtain', only that there may be several cases.
  4700 Optional case names may be specified in parentheses; these will be
  4701 available both in the present proof and as annotations in the
  4702 resulting rule, for later use with the 'cases' method (cf. attribute
  4703 case_names).
  4704 
  4705 * Isar: the assumptions of a long theorem statement are available as
  4706 "assms" fact in the proof context.  This is more appropriate than the
  4707 (historical) "prems", which refers to all assumptions of the current
  4708 context, including those from the target locale, proof body etc.
  4709 
  4710 * Isar: 'print_statement' prints theorems from the current theory or
  4711 proof context in long statement form, according to the syntax of a
  4712 top-level lemma.
  4713 
  4714 * Isar: 'obtain' takes an optional case name for the local context
  4715 introduction rule (default "that").
  4716 
  4717 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4718 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4719 to occur.
  4720 
  4721 * Pure: syntax "CONST name" produces a fully internalized constant
  4722 according to the current context.  This is particularly useful for
  4723 syntax translations that should refer to internal constant
  4724 representations independently of name spaces.
  4725 
  4726 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4727 instead of "FOO ". This allows multiple binder declarations to coexist
  4728 in the same context.  INCOMPATIBILITY.
  4729 
  4730 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4731 primitive that also works in a locale context (both for constants and
  4732 fixed variables). Type declaration and internal syntactic representation
  4733 of given constants retrieved from the context. Likewise, the
  4734 'no_notation' command allows to remove given syntax annotations from the
  4735 current context.
  4736 
  4737 * Isar/locales: new derived specification elements 'axiomatization',
  4738 'definition', 'abbreviation', which support type-inference, admit
  4739 object-level specifications (equality, equivalence).  See also the
  4740 isar-ref manual.  Examples:
  4741 
  4742   axiomatization
  4743     eq  (infix "===" 50) where
  4744     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4745 
  4746   definition "f x y = x + y + 1"
  4747   definition g where "g x = f x x"
  4748 
  4749   abbreviation
  4750     neq  (infix "=!=" 50) where
  4751     "x =!= y == ~ (x === y)"
  4752 
  4753 These specifications may be also used in a locale context.  Then the
  4754 constants being introduced depend on certain fixed parameters, and the
  4755 constant name is qualified by the locale base name.  An internal
  4756 abbreviation takes care for convenient input and output, making the
  4757 parameters implicit and using the original short name.  See also
  4758 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4759 entities from a monomorphic theory.
  4760 
  4761 Presently, abbreviations are only available 'in' a target locale, but
  4762 not inherited by general import expressions.  Also note that
  4763 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4764 'translations' in common applications.  The "no_abbrevs" print mode
  4765 prevents folding of abbreviations in term output.
  4766 
  4767 Concrete syntax is attached to specified constants in internal form,
  4768 independently of name spaces.  The parse tree representation is
  4769 slightly different -- use 'notation' instead of raw 'syntax', and
  4770 'translations' with explicit "CONST" markup to accommodate this.
  4771 
  4772 * Pure/Isar: unified syntax for new-style specification mechanisms
  4773 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4774 full type inference and dummy patterns ("_").  For example:
  4775 
  4776   definition "K x _ = x"
  4777 
  4778   inductive conj for A B
  4779   where "A ==> B ==> conj A B"
  4780 
  4781 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4782 the current context.  Print mode "no_abbrevs" prevents inversion of
  4783 abbreviations on output.
  4784 
  4785 * Isar/locales: improved parameter handling: use of locales "var" and
  4786 "struct" no longer necessary; - parameter renamings are no longer
  4787 required to be injective.  For example, this allows to define
  4788 endomorphisms as locale endom = homom mult mult h.
  4789 
  4790 * Isar/locales: changed the way locales with predicates are defined.
  4791 Instead of accumulating the specification, the imported expression is
  4792 now an interpretation.  INCOMPATIBILITY: different normal form of
  4793 locale expressions.  In particular, in interpretations of locales with
  4794 predicates, goals repesenting already interpreted fragments are not
  4795 removed automatically.  Use methods `intro_locales' and
  4796 `unfold_locales'; see below.
  4797 
  4798 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4799 provide backward reasoning on locales predicates.  The methods are
  4800 aware of interpretations and discharge corresponding goals.
  4801 `intro_locales' is less aggressive then `unfold_locales' and does not
  4802 unfold predicates to assumptions.
  4803 
  4804 * Isar/locales: the order in which locale fragments are accumulated
  4805 has changed.  This enables to override declarations from fragments due
  4806 to interpretations -- for example, unwanted simp rules.
  4807 
  4808 * Isar/locales: interpretation in theories and proof contexts has been
  4809 extended.  One may now specify (and prove) equations, which are
  4810 unfolded in interpreted theorems.  This is useful for replacing
  4811 defined concepts (constants depending on locale parameters) by
  4812 concepts already existing in the target context.  Example:
  4813 
  4814   interpretation partial_order ["op <= :: [int, int] => bool"]
  4815     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4816 
  4817 Typically, the constant `partial_order.less' is created by a
  4818 definition specification element in the context of locale
  4819 partial_order.
  4820 
  4821 * Method "induct": improved internal context management to support
  4822 local fixes and defines on-the-fly. Thus explicit meta-level
  4823 connectives !!  and ==> are rarely required anymore in inductive goals
  4824 (using object-logic connectives for this purpose has been long
  4825 obsolete anyway). Common proof patterns are explained in
  4826 src/HOL/Induct/Common_Patterns.thy, see also
  4827 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4828 examples.
  4829 
  4830 * Method "induct": improved handling of simultaneous goals. Instead of
  4831 introducing object-level conjunction, the statement is now split into
  4832 several conclusions, while the corresponding symbolic cases are nested
  4833 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4834 see src/HOL/Induct/Common_Patterns.thy, for example.
  4835 
  4836 * Method "induct": mutual induction rules are now specified as a list
  4837 of rule sharing the same induction cases. HOL packages usually provide
  4838 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4839 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4840 mutual induction rules differently, i.e. like this:
  4841 
  4842   (induct rule: foo_bar.inducts)
  4843   (induct set: foo bar)
  4844   (induct pred: foo bar)
  4845   (induct type: foo bar)
  4846 
  4847 The ML function ProjectRule.projections turns old-style rules into the
  4848 new format.
  4849 
  4850 * Method "coinduct": dual of induction, see
  4851 src/HOL/Library/Coinductive_List.thy for various examples.
  4852 
  4853 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4854 considered a legacy feature.
  4855 
  4856 * Attribute "symmetric" produces result with standardized schematic
  4857 variables (index 0).  Potential INCOMPATIBILITY.
  4858 
  4859 * Simplifier: by default the simplifier trace only shows top level
  4860 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4861 default. Thus there is less danger of being flooded by the trace. The
  4862 trace indicates where parts have been suppressed.
  4863   
  4864 * Provers/classical: removed obsolete classical version of elim_format
  4865 attribute; classical elim/dest rules are now treated uniformly when
  4866 manipulating the claset.
  4867 
  4868 * Provers/classical: stricter checks to ensure that supplied intro,
  4869 dest and elim rules are well-formed; dest and elim rules must have at
  4870 least one premise.
  4871 
  4872 * Provers/classical: attributes dest/elim/intro take an optional
  4873 weight argument for the rule (just as the Pure versions).  Weights are
  4874 ignored by automated tools, but determine the search order of single
  4875 rule steps.
  4876 
  4877 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4878 where the body does not mention the bound variable.  Note that dummy
  4879 patterns implicitly depend on their context of bounds, which makes
  4880 "{_. _}" match any set comprehension as expected.  Potential
  4881 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4882 constant "_idtdummy" in the binding position.
  4883 
  4884 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4885 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4886 for example "A -> B" => "Pi A (%_. B)".
  4887 
  4888 * Pure: 'class_deps' command visualizes the subclass relation, using
  4889 the graph browser tool.
  4890 
  4891 * Pure: 'print_theory' now suppresses certain internal declarations by
  4892 default; use '!' option for full details.
  4893 
  4894 
  4895 *** HOL ***
  4896 
  4897 * Method "metis" proves goals by applying the Metis general-purpose
  4898 resolution prover (see also http://gilith.com/software/metis/).
  4899 Examples are in the directory MetisExamples.  WARNING: the
  4900 Isabelle/HOL-Metis integration does not yet work properly with
  4901 multi-threading.
  4902   
  4903 * Command 'sledgehammer' invokes external automatic theorem provers as
  4904 background processes.  It generates calls to the "metis" method if
  4905 successful. These can be pasted into the proof.  Users do not have to
  4906 wait for the automatic provers to return.  WARNING: does not really
  4907 work with multi-threading.
  4908 
  4909 * New "auto_quickcheck" feature tests outermost goal statements for
  4910 potential counter-examples.  Controlled by ML references
  4911 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4912 5000 milliseconds).  Fails silently if statements is outside of
  4913 executable fragment, or any other codgenerator problem occurs.
  4914 
  4915 * New constant "undefined" with axiom "undefined x = undefined".
  4916 
  4917 * Added class "HOL.eq", allowing for code generation with polymorphic
  4918 equality.
  4919 
  4920 * Some renaming of class constants due to canonical name prefixing in
  4921 the new 'class' package:
  4922 
  4923     HOL.abs ~> HOL.abs_class.abs
  4924     HOL.divide ~> HOL.divide_class.divide
  4925     0 ~> HOL.zero_class.zero
  4926     1 ~> HOL.one_class.one
  4927     op + ~> HOL.plus_class.plus
  4928     op - ~> HOL.minus_class.minus
  4929     uminus ~> HOL.minus_class.uminus
  4930     op * ~> HOL.times_class.times
  4931     op < ~> HOL.ord_class.less
  4932     op <= > HOL.ord_class.less_eq
  4933     Nat.power ~> Power.power_class.power
  4934     Nat.size ~> Nat.size_class.size
  4935     Numeral.number_of ~> Numeral.number_class.number_of
  4936     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4937     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4938     Orderings.min ~> Orderings.ord_class.min
  4939     Orderings.max ~> Orderings.ord_class.max
  4940     Divides.op div ~> Divides.div_class.div
  4941     Divides.op mod ~> Divides.div_class.mod
  4942     Divides.op dvd ~> Divides.div_class.dvd
  4943 
  4944 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4945 
  4946 a) User-defined constants using any of the names "plus", "minus",
  4947 "times", "less" or "less_eq". The standard syntax translations for
  4948 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4949 names.
  4950 
  4951 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4952 INCOMPATIBILITY: use more specific names.
  4953 
  4954 c) Permutative equations (e.g. "a + b = b + a")
  4955 Since the change of names also changes the order of terms, permutative
  4956 rewrite rules may get applied in a different order. Experience shows
  4957 that this is rarely the case (only two adaptions in the whole Isabelle
  4958 distribution).  INCOMPATIBILITY: rewrite proofs
  4959 
  4960 d) ML code directly refering to constant names
  4961 This in general only affects hand-written proof tactics, simprocs and
  4962 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4963 Consider using @{const_name} antiquotation.
  4964 
  4965 * New class "default" with associated constant "default".
  4966 
  4967 * Function "sgn" is now overloaded and available on int, real, complex
  4968 (and other numeric types), using class "sgn".  Two possible defs of
  4969 sgn are given as equational assumptions in the classes sgn_if and
  4970 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4971 INCOMPATIBILITY.
  4972 
  4973 * Locale "partial_order" now unified with class "order" (cf. theory
  4974 Orderings), added parameter "less".  INCOMPATIBILITY.
  4975 
  4976 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4977 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4978 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4979 
  4980 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4981 changed order of proof goals in instance proofs.
  4982 
  4983 * The transitivity reasoner for partial and linear orders is set up
  4984 for classes "order" and "linorder".  Instances of the reasoner are available
  4985 in all contexts importing or interpreting the corresponding locales.
  4986 Method "order" invokes the reasoner separately; the reasoner
  4987 is also integrated with the Simplifier as a solver.  Diagnostic
  4988 command 'print_orders' shows the available instances of the reasoner
  4989 in the current context.
  4990 
  4991 * Localized monotonicity predicate in theory "Orderings"; integrated
  4992 lemmas max_of_mono and min_of_mono with this predicate.
  4993 INCOMPATIBILITY.
  4994 
  4995 * Formulation of theorem "dense" changed slightly due to integration
  4996 with new class dense_linear_order.
  4997 
  4998 * Uniform lattice theory development in HOL.
  4999 
  5000     constants "meet" and "join" now named "inf" and "sup"
  5001     constant "Meet" now named "Inf"
  5002 
  5003     classes "meet_semilorder" and "join_semilorder" now named
  5004       "lower_semilattice" and "upper_semilattice"
  5005     class "lorder" now named "lattice"
  5006     class "comp_lat" now named "complete_lattice"
  5007 
  5008     Instantiation of lattice classes allows explicit definitions
  5009     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  5010 
  5011   INCOMPATIBILITY.  Theorem renames:
  5012 
  5013     meet_left_le            ~> inf_le1
  5014     meet_right_le           ~> inf_le2
  5015     join_left_le            ~> sup_ge1
  5016     join_right_le           ~> sup_ge2
  5017     meet_join_le            ~> inf_sup_ord
  5018     le_meetI                ~> le_infI
  5019     join_leI                ~> le_supI
  5020     le_meet                 ~> le_inf_iff
  5021     le_join                 ~> ge_sup_conv
  5022     meet_idempotent         ~> inf_idem
  5023     join_idempotent         ~> sup_idem
  5024     meet_comm               ~> inf_commute
  5025     join_comm               ~> sup_commute
  5026     meet_leI1               ~> le_infI1
  5027     meet_leI2               ~> le_infI2
  5028     le_joinI1               ~> le_supI1
  5029     le_joinI2               ~> le_supI2
  5030     meet_assoc              ~> inf_assoc
  5031     join_assoc              ~> sup_assoc
  5032     meet_left_comm          ~> inf_left_commute
  5033     meet_left_idempotent    ~> inf_left_idem
  5034     join_left_comm          ~> sup_left_commute
  5035     join_left_idempotent    ~> sup_left_idem
  5036     meet_aci                ~> inf_aci
  5037     join_aci                ~> sup_aci
  5038     le_def_meet             ~> le_iff_inf
  5039     le_def_join             ~> le_iff_sup
  5040     join_absorp2            ~> sup_absorb2
  5041     join_absorp1            ~> sup_absorb1
  5042     meet_absorp1            ~> inf_absorb1
  5043     meet_absorp2            ~> inf_absorb2
  5044     meet_join_absorp        ~> inf_sup_absorb
  5045     join_meet_absorp        ~> sup_inf_absorb
  5046     distrib_join_le         ~> distrib_sup_le
  5047     distrib_meet_le         ~> distrib_inf_le
  5048 
  5049     add_meet_distrib_left   ~> add_inf_distrib_left
  5050     add_join_distrib_left   ~> add_sup_distrib_left
  5051     is_join_neg_meet        ~> is_join_neg_inf
  5052     is_meet_neg_join        ~> is_meet_neg_sup
  5053     add_meet_distrib_right  ~> add_inf_distrib_right
  5054     add_join_distrib_right  ~> add_sup_distrib_right
  5055     add_meet_join_distribs  ~> add_sup_inf_distribs
  5056     join_eq_neg_meet        ~> sup_eq_neg_inf
  5057     meet_eq_neg_join        ~> inf_eq_neg_sup
  5058     add_eq_meet_join        ~> add_eq_inf_sup
  5059     meet_0_imp_0            ~> inf_0_imp_0
  5060     join_0_imp_0            ~> sup_0_imp_0
  5061     meet_0_eq_0             ~> inf_0_eq_0
  5062     join_0_eq_0             ~> sup_0_eq_0
  5063     neg_meet_eq_join        ~> neg_inf_eq_sup
  5064     neg_join_eq_meet        ~> neg_sup_eq_inf
  5065     join_eq_if              ~> sup_eq_if
  5066 
  5067     mono_meet               ~> mono_inf
  5068     mono_join               ~> mono_sup
  5069     meet_bool_eq            ~> inf_bool_eq
  5070     join_bool_eq            ~> sup_bool_eq
  5071     meet_fun_eq             ~> inf_fun_eq
  5072     join_fun_eq             ~> sup_fun_eq
  5073     meet_set_eq             ~> inf_set_eq
  5074     join_set_eq             ~> sup_set_eq
  5075     meet1_iff               ~> inf1_iff
  5076     meet2_iff               ~> inf2_iff
  5077     meet1I                  ~> inf1I
  5078     meet2I                  ~> inf2I
  5079     meet1D1                 ~> inf1D1
  5080     meet2D1                 ~> inf2D1
  5081     meet1D2                 ~> inf1D2
  5082     meet2D2                 ~> inf2D2
  5083     meet1E                  ~> inf1E
  5084     meet2E                  ~> inf2E
  5085     join1_iff               ~> sup1_iff
  5086     join2_iff               ~> sup2_iff
  5087     join1I1                 ~> sup1I1
  5088     join2I1                 ~> sup2I1
  5089     join1I1                 ~> sup1I1
  5090     join2I2                 ~> sup1I2
  5091     join1CI                 ~> sup1CI
  5092     join2CI                 ~> sup2CI
  5093     join1E                  ~> sup1E
  5094     join2E                  ~> sup2E
  5095 
  5096     is_meet_Meet            ~> is_meet_Inf
  5097     Meet_bool_def           ~> Inf_bool_def
  5098     Meet_fun_def            ~> Inf_fun_def
  5099     Meet_greatest           ~> Inf_greatest
  5100     Meet_lower              ~> Inf_lower
  5101     Meet_set_def            ~> Inf_set_def
  5102 
  5103     Sup_def                 ~> Sup_Inf
  5104     Sup_bool_eq             ~> Sup_bool_def
  5105     Sup_fun_eq              ~> Sup_fun_def
  5106     Sup_set_eq              ~> Sup_set_def
  5107 
  5108     listsp_meetI            ~> listsp_infI
  5109     listsp_meet_eq          ~> listsp_inf_eq
  5110 
  5111     meet_min                ~> inf_min
  5112     join_max                ~> sup_max
  5113 
  5114 * Added syntactic class "size"; overloaded constant "size" now has
  5115 type "'a::size ==> bool"
  5116 
  5117 * Internal reorganisation of `size' of datatypes: size theorems
  5118 "foo.size" are no longer subsumed by "foo.simps" (but are still
  5119 simplification rules by default!); theorems "prod.size" now named
  5120 "*.size".
  5121 
  5122 * Class "div" now inherits from class "times" rather than "type".
  5123 INCOMPATIBILITY.
  5124 
  5125 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  5126 Linorder etc.  have disappeared; operations defined in terms of
  5127 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  5128 
  5129 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  5130 
  5131 * HOL-Word: New extensive library and type for generic, fixed size
  5132 machine words, with arithemtic, bit-wise, shifting and rotating
  5133 operations, reflection into int, nat, and bool lists, automation for
  5134 linear arithmetic (by automatic reflection into nat or int), including
  5135 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  5136 arithmetic type classes, supporting automatic simplification of
  5137 numerals on all operations.
  5138 
  5139 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  5140 
  5141 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  5142 
  5143 * Code generator library theories:
  5144   - Code_Integer represents HOL integers by big integer literals in target
  5145     languages.
  5146   - Code_Char represents HOL characters by character literals in target
  5147     languages.
  5148   - Code_Char_chr like Code_Char, but also offers treatment of character
  5149     codes; includes Code_Integer.
  5150   - Executable_Set allows to generate code for finite sets using lists.
  5151   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  5152     denominator).
  5153   - Executable_Real implements a subset of real numbers, namly those
  5154     representable by rational numbers.
  5155   - Efficient_Nat implements natural numbers by integers, which in general will
  5156     result in higher efficency; pattern matching with 0/Suc is eliminated;
  5157     includes Code_Integer.
  5158   - Code_Index provides an additional datatype index which is mapped to
  5159     target-language built-in integers.
  5160   - Code_Message provides an additional datatype message_string which is isomorphic to
  5161     strings; messages are mapped to target-language strings.
  5162 
  5163 * New package for inductive predicates
  5164 
  5165   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  5166 
  5167     inductive
  5168       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5169       for z_1 :: U_1 and ... and z_n :: U_m
  5170     where
  5171       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5172     | ...
  5173 
  5174   with full support for type-inference, rather than
  5175 
  5176     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5177 
  5178     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5179     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5180 
  5181     inductive "s z_1 ... z_m"
  5182     intros
  5183       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5184       ...
  5185 
  5186   For backward compatibility, there is a wrapper allowing inductive
  5187   sets to be defined with the new package via
  5188 
  5189     inductive_set
  5190       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5191       for z_1 :: U_1 and ... and z_n :: U_m
  5192     where
  5193       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5194     | ...
  5195 
  5196   or
  5197 
  5198     inductive_set
  5199       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5200       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5201       for z_1 :: U_1 and ... and z_n :: U_m
  5202     where
  5203       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5204     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5205     | ...
  5206 
  5207   if the additional syntax "p ..." is required.
  5208 
  5209   Numerous examples can be found in the subdirectories src/HOL/Auth,
  5210   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  5211 
  5212   INCOMPATIBILITIES:
  5213 
  5214   - Since declaration and definition of inductive sets or predicates
  5215     is no longer separated, abbreviations involving the newly
  5216     introduced sets or predicates must be specified together with the
  5217     introduction rules after the 'where' keyword (see above), rather
  5218     than before the actual inductive definition.
  5219 
  5220   - The variables in induction and elimination rules are now
  5221     quantified in the order of their occurrence in the introduction
  5222     rules, rather than in alphabetical order. Since this may break
  5223     some proofs, these proofs either have to be repaired, e.g. by
  5224     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  5225     statements of the form
  5226 
  5227       case (rule_i a_i_1 ... a_i_{k_i})
  5228 
  5229     or the old order of quantification has to be restored by explicitly adding
  5230     meta-level quantifiers in the introduction rules, i.e.
  5231 
  5232       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  5233 
  5234   - The format of the elimination rules is now
  5235 
  5236       p z_1 ... z_m x_1 ... x_n ==>
  5237         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5238         ==> ... ==> P
  5239 
  5240     for predicates and
  5241 
  5242       (x_1, ..., x_n) : s z_1 ... z_m ==>
  5243         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5244         ==> ... ==> P
  5245 
  5246     for sets rather than
  5247 
  5248       x : s z_1 ... z_m ==>
  5249         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  5250         ==> ... ==> P
  5251 
  5252     This may require terms in goals to be expanded to n-tuples
  5253     (e.g. using case_tac or simplification with the split_paired_all
  5254     rule) before the above elimination rule is applicable.
  5255 
  5256   - The elimination or case analysis rules for (mutually) inductive
  5257     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  5258     list of rules "p_1_..._p_k.elims" is no longer available.
  5259 
  5260 * New package "function"/"fun" for general recursive functions,
  5261 supporting mutual and nested recursion, definitions in local contexts,
  5262 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  5263 for small examples, and the separate tutorial on the function
  5264 package. The old recdef "package" is still available as before, but
  5265 users are encouraged to use the new package.
  5266 
  5267 * Method "lexicographic_order" automatically synthesizes termination
  5268 relations as lexicographic combinations of size measures. 
  5269 
  5270 * Case-expressions allow arbitrary constructor-patterns (including
  5271 "_") and take their order into account, like in functional
  5272 programming.  Internally, this is translated into nested
  5273 case-expressions; missing cases are added and mapped to the predefined
  5274 constant "undefined". In complicated cases printing may no longer show
  5275 the original input but the internal form. Lambda-abstractions allow
  5276 the same form of pattern matching: "% pat1 => e1 | ..." is an
  5277 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  5278 variable.
  5279 
  5280 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  5281 is an abbreviation for "of_nat :: nat => int". The simplification
  5282 rules for "of_nat" have been changed to work like "int" did
  5283 previously.  Potential INCOMPATIBILITY:
  5284   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  5285   - of_nat_diff and of_nat_mult are no longer default simp rules
  5286 
  5287 * Method "algebra" solves polynomial equations over (semi)rings using
  5288 Groebner bases. The (semi)ring structure is defined by locales and the
  5289 tool setup depends on that generic context. Installing the method for
  5290 a specific type involves instantiating the locale and possibly adding
  5291 declarations for computation on the coefficients.  The method is
  5292 already instantiated for natural numbers and for the axiomatic class
  5293 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  5294 CALCULEMUS 2007 for the general principles underlying this
  5295 architecture of context-aware proof-tools.
  5296 
  5297 * Method "ferrack" implements quantifier elimination over
  5298 special-purpose dense linear orders using locales (analogous to
  5299 "algebra"). The method is already installed for class
  5300 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  5301 rat, etc.
  5302 
  5303 * Former constant "List.op @" now named "List.append".  Use ML
  5304 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  5305 circumvent possible incompatibilities when working on ML level.
  5306 
  5307 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  5308 
  5309 * New function listsum :: 'a list => 'a for arbitrary monoids.
  5310 Special syntax: "SUM x <- xs. f x" (and latex variants)
  5311 
  5312 * New syntax for Haskell-like list comprehension (input only), eg.
  5313 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  5314 
  5315 * The special syntax for function "filter" has changed from [x :
  5316 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  5317 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  5318 
  5319 * [a..b] is now defined for arbitrary linear orders.  It used to be
  5320 defined on nat only, as an abbreviation for [a..<Suc b]
  5321 INCOMPATIBILITY.
  5322 
  5323 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  5324 
  5325 * New functions "sorted" and "sort" in src/HOL/List.thy.
  5326 
  5327 * New lemma collection field_simps (an extension of ring_simps) for
  5328 manipulating (in)equations involving division. Multiplies with all
  5329 denominators that can be proved to be non-zero (in equations) or
  5330 positive/negative (in inequations).
  5331 
  5332 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  5333 have been improved and renamed to ring_simps, group_simps and
  5334 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  5335 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  5336 
  5337 * Theory Library/Commutative_Ring: switched from recdef to function
  5338 package; constants add, mul, pow now curried.  Infix syntax for
  5339 algebraic operations.
  5340 
  5341 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  5342 INCOMPATIBILITY.
  5343 
  5344 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  5345 INCOMPATIBILITY.
  5346 
  5347 * HOL/records: generalised field-update to take a function on the
  5348 field rather than the new value: r(|A := x|) is translated to A_update
  5349 (K x) r The K-combinator that is internally used is called K_record.
  5350 INCOMPATIBILITY: Usage of the plain update functions has to be
  5351 adapted.
  5352  
  5353 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  5354 * x = 0, which are required for a semiring.  Richer structures do not
  5355 inherit from semiring_0 anymore, because this property is a theorem
  5356 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  5357 there is more to prove, but this is mostly trivial.
  5358 
  5359 * Class "recpower" is generalized to arbitrary monoids, not just
  5360 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  5361 commutativity or semiring properties additionally.
  5362 
  5363 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  5364 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  5365 better use 'abbreviation'.
  5366 
  5367 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  5368 
  5369 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  5370 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  5371 significant changes for setting up numeral syntax for types:
  5372   - New constants Numeral.pred and Numeral.succ instead
  5373       of former Numeral.bin_pred and Numeral.bin_succ.
  5374   - Use integer operations instead of bin_add, bin_mult and so on.
  5375   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  5376   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  5377 
  5378 See src/HOL/Integ/IntArith.thy for an example setup.
  5379 
  5380 * Command 'normal_form' computes the normal form of a term that may
  5381 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  5382 produces ``[b, c, a]'' (without proof).  This command is suitable for
  5383 heavy-duty computations because the functions are compiled to ML
  5384 first.  Correspondingly, a method "normalization" is provided.  See
  5385 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  5386 
  5387 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  5388 25 like -->); output depends on the "iff" print_mode, the default is
  5389 "A = B" (with priority 50).
  5390 
  5391 * Relations less (<) and less_eq (<=) are also available on type bool.
  5392 Modified syntax to disallow nesting without explicit parentheses,
  5393 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  5394 INCOMPATIBILITY.
  5395 
  5396 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  5397 
  5398 * Relation composition operator "op O" now has precedence 75 and binds
  5399 stronger than union and intersection. INCOMPATIBILITY.
  5400 
  5401 * The old set interval syntax "{m..n(}" (and relatives) has been
  5402 removed.  Use "{m..<n}" (and relatives) instead.
  5403 
  5404 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  5405 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  5406 ``declare [[simproc del: neq]]''.
  5407 
  5408 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  5409 True/False.
  5410 
  5411 * Theorem Cons_eq_map_conv no longer declared as "simp".
  5412 
  5413 * Theorem setsum_mult renamed to setsum_right_distrib.
  5414 
  5415 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  5416 ``rule'' method.
  5417 
  5418 * Reimplemented methods "sat" and "satx", with several improvements:
  5419 goals no longer need to be stated as "<prems> ==> False", equivalences
  5420 (i.e. "=" on type bool) are handled, variable names of the form
  5421 "lit_<n>" are no longer reserved, significant speedup.
  5422 
  5423 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  5424 zChaff is still supported as well.
  5425 
  5426 * 'inductive' and 'datatype': provide projections of mutual rules,
  5427 bundled as foo_bar.inducts;
  5428 
  5429 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  5430 Library.
  5431 
  5432 * Library: moved theory Accessible_Part to main HOL.
  5433 
  5434 * Library: added theory Coinductive_List of potentially infinite lists
  5435 as greatest fixed-point.
  5436 
  5437 * Library: added theory AssocList which implements (finite) maps as
  5438 association lists.
  5439 
  5440 * Method "evaluation" solves goals (i.e. a boolean expression)
  5441 efficiently by compiling it to ML.  The goal is "proved" (via an
  5442 oracle) if it evaluates to True.
  5443 
  5444 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  5445 also when invoked by the simplifier.  This results in the Simplifier
  5446 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  5447 Configuration option fast_arith_split_limit=0 recovers the old
  5448 behavior.
  5449 
  5450 * Support for hex (0x20) and binary (0b1001) numerals.
  5451 
  5452 * New method: reify eqs (t), where eqs are equations for an
  5453 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  5454 parameter, computes a term s::'b and a list xs::'a list and proves the
  5455 theorem I xs s = t. This is also known as reification or quoting. The
  5456 resulting theorem is applied to the subgoal to substitute t with I xs
  5457 s.  If t is omitted, the subgoal itself is reified.
  5458 
  5459 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  5460 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  5461 where f is supposed to be a computable function (in the sense of code
  5462 generattion). The method uses reify to compute s and xs as above then
  5463 applies corr_thm and uses normalization by evaluation to "prove" f s =
  5464 r and finally gets the theorem t = r, which is again applied to the
  5465 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  5466 
  5467 * Reflection: Automatic reification now handels binding, an example is
  5468 available in src/HOL/ex/ReflectionEx.thy
  5469 
  5470 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  5471 command 'statespace' that is similar to 'record', but introduces an
  5472 abstract specification based on the locale infrastructure instead of
  5473 HOL types.  This leads to extra flexibility in composing state spaces,
  5474 in particular multiple inheritance and renaming of components.
  5475 
  5476 
  5477 *** HOL-Complex ***
  5478 
  5479 * Hyperreal: Functions root and sqrt are now defined on negative real
  5480 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  5481 Nonnegativity side conditions have been removed from many lemmas, so
  5482 that more subgoals may now be solved by simplification; potential
  5483 INCOMPATIBILITY.
  5484 
  5485 * Real: new type classes formalize real normed vector spaces and
  5486 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  5487 and norm :: 'a => real.
  5488 
  5489 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  5490 reals into other types. The overloaded constant Reals :: 'a set is now
  5491 defined as range of_real; potential INCOMPATIBILITY.
  5492 
  5493 * Real: proper support for ML code generation, including 'quickcheck'.
  5494 Reals are implemented as arbitrary precision rationals.
  5495 
  5496 * Hyperreal: Several constants that previously worked only for the
  5497 reals have been generalized, so they now work over arbitrary vector
  5498 spaces. Type annotations may need to be added in some cases; potential
  5499 INCOMPATIBILITY.
  5500 
  5501   Infinitesimal  :: ('a::real_normed_vector) star set
  5502   HFinite        :: ('a::real_normed_vector) star set
  5503   HInfinite      :: ('a::real_normed_vector) star set
  5504   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5505   monad          :: ('a::real_normed_vector) star => 'a star set
  5506   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5507   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5508   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5509   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5510   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5511   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5512   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5513   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5514   sgn            :: 'a::real_normed_vector => 'a
  5515   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5516 
  5517 * Complex: Some complex-specific constants are now abbreviations for
  5518 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5519 hnorm.  Other constants have been entirely removed in favor of the
  5520 polymorphic versions (INCOMPATIBILITY):
  5521 
  5522   approx        <-- capprox
  5523   HFinite       <-- CFinite
  5524   HInfinite     <-- CInfinite
  5525   Infinitesimal <-- CInfinitesimal
  5526   monad         <-- cmonad
  5527   galaxy        <-- cgalaxy
  5528   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5529   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5530   (ns)deriv     <-- (ns)cderiv
  5531 
  5532 
  5533 *** HOL-Algebra ***
  5534 
  5535 * Formalisation of ideals and the quotient construction over rings.
  5536 
  5537 * Order and lattice theory no longer based on records.
  5538 INCOMPATIBILITY.
  5539 
  5540 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5541 greatest_closed.  INCOMPATIBILITY.
  5542 
  5543 * Method algebra is now set up via an attribute.  For examples see
  5544 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5545 of algebraic structures.
  5546 
  5547 * Renamed theory CRing to Ring.
  5548 
  5549 
  5550 *** HOL-Nominal ***
  5551 
  5552 * Substantial, yet incomplete support for nominal datatypes (binding
  5553 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5554 src/HOL/Nominal/Examples.  Prospective users should consult
  5555 http://isabelle.in.tum.de/nominal/
  5556 
  5557 
  5558 *** ML ***
  5559 
  5560 * ML basics: just one true type int, which coincides with IntInf.int
  5561 (even on SML/NJ).
  5562 
  5563 * ML within Isar: antiquotations allow to embed statically-checked
  5564 formal entities in the source, referring to the context available at
  5565 compile-time.  For example:
  5566 
  5567 ML {* @{sort "{zero,one}"} *}
  5568 ML {* @{typ "'a => 'b"} *}
  5569 ML {* @{term "%x. x"} *}
  5570 ML {* @{prop "x == y"} *}
  5571 ML {* @{ctyp "'a => 'b"} *}
  5572 ML {* @{cterm "%x. x"} *}
  5573 ML {* @{cprop "x == y"} *}
  5574 ML {* @{thm asm_rl} *}
  5575 ML {* @{thms asm_rl} *}
  5576 ML {* @{type_name c} *}
  5577 ML {* @{type_syntax c} *}
  5578 ML {* @{const_name c} *}
  5579 ML {* @{const_syntax c} *}
  5580 ML {* @{context} *}
  5581 ML {* @{theory} *}
  5582 ML {* @{theory Pure} *}
  5583 ML {* @{theory_ref} *}
  5584 ML {* @{theory_ref Pure} *}
  5585 ML {* @{simpset} *}
  5586 ML {* @{claset} *}
  5587 ML {* @{clasimpset} *}
  5588 
  5589 The same works for sources being ``used'' within an Isar context.
  5590 
  5591 * ML in Isar: improved error reporting; extra verbosity with
  5592 ML_Context.trace enabled.
  5593 
  5594 * Pure/General/table.ML: the join operations now works via exceptions
  5595 DUP/SAME instead of type option. This is simpler in simple cases, and
  5596 admits slightly more efficient complex applications.
  5597 
  5598 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5599 use Context.generic instead of just theory.
  5600 
  5601 * Pure: datatype Context.generic joins theory/Proof.context and
  5602 provides some facilities for code that works in either kind of
  5603 context, notably GenericDataFun for uniform theory and proof data.
  5604 
  5605 * Pure: simplified internal attribute type, which is now always
  5606 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5607 local (Proof.context) attributes have been discontinued, while
  5608 minimizing code duplication. Thm.rule_attribute and
  5609 Thm.declaration_attribute build canonical attributes; see also structure
  5610 Context for further operations on Context.generic, notably
  5611 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5612 declarations and definitions.
  5613 
  5614 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5615 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5616 init only required for impure data. INCOMPATIBILITY: empty really need
  5617 to be empty (no dependencies on theory content!)
  5618 
  5619 * Pure/kernel: consts certification ignores sort constraints given in
  5620 signature declarations. (This information is not relevant to the
  5621 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5622 potential INCOMPATIBILITY.
  5623 
  5624 * Pure: axiomatic type classes are now purely definitional, with
  5625 explicit proofs of class axioms and super class relations performed
  5626 internally. See Pure/axclass.ML for the main internal interfaces --
  5627 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5628 AxClass.axiomatize_class/classrel/arity supersede
  5629 Sign.add_classes/classrel/arities.
  5630 
  5631 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5632 global/local versions on theory vs. Proof.context have been
  5633 discontinued; Attrib.syntax and Method.syntax have been adapted
  5634 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5635 attributes, methods, etc.
  5636 
  5637 * Pure: several functions of signature "... -> theory -> theory * ..."
  5638 have been reoriented to "... -> theory -> ... * theory" in order to
  5639 allow natural usage in combination with the ||>, ||>>, |-> and
  5640 fold_map combinators.
  5641 
  5642 * Pure: official theorem names (closed derivations) and additional
  5643 comments (tags) are now strictly separate.  Name hints -- which are
  5644 maintained as tags -- may be attached any time without affecting the
  5645 derivation.
  5646 
  5647 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5648 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5649 achieve the old behaviour.
  5650 
  5651 * Pure: the "Goal" constant is now called "prop", supporting a
  5652 slightly more general idea of ``protecting'' meta-level rule
  5653 statements.
  5654 
  5655 * Pure: Logic.(un)varify only works in a global context, which is now
  5656 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5657 Logic.legacy_(un)varify as temporary workaround.
  5658 
  5659 * Pure: structure Name provides scalable operations for generating
  5660 internal variable names, notably Name.variants etc.  This replaces
  5661 some popular functions from term.ML:
  5662 
  5663   Term.variant		->  Name.variant
  5664   Term.variantlist	->  Name.variant_list
  5665   Term.invent_names	->  Name.invent_list
  5666 
  5667 Note that low-level renaming rarely occurs in new code -- operations
  5668 from structure Variable are used instead (see below).
  5669 
  5670 * Pure: structure Variable provides fundamental operations for proper
  5671 treatment of fixed/schematic variables in a context.  For example,
  5672 Variable.import introduces fixes for schematics of given facts and
  5673 Variable.export reverses the effect (up to renaming) -- this replaces
  5674 various freeze_thaw operations.
  5675 
  5676 * Pure: structure Goal provides simple interfaces for
  5677 init/conclude/finish and tactical prove operations (replacing former
  5678 Tactic.prove).  Goal.prove is the canonical way to prove results
  5679 within a given context; Goal.prove_global is a degraded version for
  5680 theory level goals, including a global Drule.standard.  Note that
  5681 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5682 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5683 in a locale context).
  5684 
  5685 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5686 and type checking (Syntax.check_term etc.), with common combinations
  5687 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5688 which are considered legacy and await removal.
  5689 
  5690 * Pure/Syntax: generic interfaces for type unchecking
  5691 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5692 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5693 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5694 available for convenience, but refer to the very same operations using
  5695 a mere theory instead of a full context.
  5696 
  5697 * Isar: simplified treatment of user-level errors, using exception
  5698 ERROR of string uniformly.  Function error now merely raises ERROR,
  5699 without any side effect on output channels.  The Isar toplevel takes
  5700 care of proper display of ERROR exceptions.  ML code may use plain
  5701 handle/can/try; cat_error may be used to concatenate errors like this:
  5702 
  5703   ... handle ERROR msg => cat_error msg "..."
  5704 
  5705 Toplevel ML code (run directly or through the Isar toplevel) may be
  5706 embedded into the Isar toplevel with exception display/debug like
  5707 this:
  5708 
  5709   Isar.toplevel (fn () => ...)
  5710 
  5711 INCOMPATIBILITY, removed special transform_error facilities, removed
  5712 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5713 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5714 -- use plain ERROR instead.
  5715 
  5716 * Isar: theory setup now has type (theory -> theory), instead of a
  5717 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5718 
  5719 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5720 ProofContext.debug/verbose flags.
  5721 
  5722 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5723 theory before entering a proof state.  Transactions now always see a
  5724 quasi-functional intermediate checkpoint, both in interactive and
  5725 batch mode.
  5726 
  5727 * Isar: simplified interfaces for outer syntax.  Renamed
  5728 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5729 OuterSyntax.add_parsers -- this functionality is now included in
  5730 OuterSyntax.command etc.  INCOMPATIBILITY.
  5731 
  5732 * Simplifier: the simpset of a running simplification process now
  5733 contains a proof context (cf. Simplifier.the_context), which is the
  5734 very context that the initial simpset has been retrieved from (by
  5735 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5736 (solver, looper etc.) may depend on arbitrary proof data.
  5737 
  5738 * Simplifier.inherit_context inherits the proof context (plus the
  5739 local bounds) of the current simplification process; any simproc
  5740 etc. that calls the Simplifier recursively should do this!  Removed
  5741 former Simplifier.inherit_bounds, which is already included here --
  5742 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5743 specify an explicit context using Simplifier.context/theory_context.
  5744 
  5745 * Simplifier/Classical Reasoner: more abstract interfaces
  5746 change_simpset/claset for modifying the simpset/claset reference of a
  5747 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5748 INCOMPATIBILITY.
  5749 
  5750 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5751 "Trueprop" etc.
  5752 
  5753 
  5754 *** System ***
  5755 
  5756 * settings: the default heap location within ISABELLE_HOME_USER now
  5757 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5758 Isabelle installations.
  5759 
  5760 * isabelle-process: option -S (secure mode) disables some critical
  5761 operations, notably runtime compilation and evaluation of ML source
  5762 code.
  5763 
  5764 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5765 
  5766 * Support for parallel execution, using native multicore support of
  5767 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5768 independent theories, according to the given theory header
  5769 specifications. The maximum number of worker threads is specified via
  5770 usedir option -M or the "max-threads" setting in Proof General. A
  5771 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5772 to 6 on a 8-core machine.  User-code needs to observe certain
  5773 guidelines for thread-safe programming, see appendix A in the Isar
  5774 Implementation manual.
  5775 
  5776 
  5777 
  5778 New in Isabelle2005 (October 2005)
  5779 ----------------------------------
  5780 
  5781 *** General ***
  5782 
  5783 * Theory headers: the new header syntax for Isar theories is
  5784 
  5785   theory <name>
  5786   imports <theory1> ... <theoryN>
  5787   uses <file1> ... <fileM>
  5788   begin
  5789 
  5790 where the 'uses' part is optional.  The previous syntax
  5791 
  5792   theory <name> = <theory1> + ... + <theoryN>:
  5793 
  5794 will disappear in the next release.  Use isatool fixheaders to convert
  5795 existing theory files.  Note that there is no change in ancient
  5796 non-Isar theories now, but these will disappear soon.
  5797 
  5798 * Theory loader: parent theories can now also be referred to via
  5799 relative and absolute paths.
  5800 
  5801 * Command 'find_theorems' searches for a list of criteria instead of a
  5802 list of constants. Known criteria are: intro, elim, dest, name:string,
  5803 simp:term, and any term. Criteria can be preceded by '-' to select
  5804 theorems that do not match. Intro, elim, dest select theorems that
  5805 match the current goal, name:s selects theorems whose fully qualified
  5806 name contain s, and simp:term selects all simplification rules whose
  5807 lhs match term.  Any other term is interpreted as pattern and selects
  5808 all theorems matching the pattern. Available in ProofGeneral under
  5809 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5810 
  5811   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5812 
  5813 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5814 matching the current goal as introduction rule and not having "HOL."
  5815 in their name (i.e. not being defined in theory HOL).
  5816 
  5817 * Command 'thms_containing' has been discontinued in favour of
  5818 'find_theorems'; INCOMPATIBILITY.
  5819 
  5820 * Communication with Proof General is now 8bit clean, which means that
  5821 Unicode text in UTF-8 encoding may be used within theory texts (both
  5822 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5823 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5824 
  5825   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5826   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5827 
  5828 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5829 Classical Reasoner.  Typical big applications run around 2 times
  5830 faster.
  5831 
  5832 
  5833 *** Document preparation ***
  5834 
  5835 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5836 of raw sources.  Only those symbols that do not require additional
  5837 LaTeX packages (depending on comments in isabellesym.sty) are
  5838 displayed properly, everything else is left verbatim.  isatool display
  5839 and isatool print are used as front ends (these are subject to the
  5840 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5841 
  5842 * Command tags control specific markup of certain regions of text,
  5843 notably folding and hiding.  Predefined tags include "theory" (for
  5844 theory begin and end), "proof" for proof commands, and "ML" for
  5845 commands involving ML code; the additional tags "visible" and
  5846 "invisible" are unused by default.  Users may give explicit tag
  5847 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5848 interpretation of tags is determined by the LaTeX job during document
  5849 preparation: see option -V of isatool usedir, or options -n and -t of
  5850 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5851 \isadroptag.
  5852 
  5853 Several document versions may be produced at the same time via isatool
  5854 usedir (the generated index.html will link all of them).  Typical
  5855 specifications include ''-V document=theory,proof,ML'' to present
  5856 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5857 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5858 these parts without any formal replacement text.  The Isabelle site
  5859 default settings produce ''document'' and ''outline'' versions as
  5860 specified above.
  5861 
  5862 * Several new antiquotations:
  5863 
  5864   @{term_type term} prints a term with its type annotated;
  5865 
  5866   @{typeof term} prints the type of a term;
  5867 
  5868   @{const const} is the same as @{term const}, but checks that the
  5869   argument is a known logical constant;
  5870 
  5871   @{term_style style term} and @{thm_style style thm} print a term or
  5872   theorem applying a "style" to it
  5873 
  5874   @{ML text}
  5875 
  5876 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5877 definitions, equations, inequations etc., 'concl' printing only the
  5878 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5879 to print the specified premise.  TermStyle.add_style provides an ML
  5880 interface for introducing further styles.  See also the "LaTeX Sugar"
  5881 document practical applications.  The ML antiquotation prints
  5882 type-checked ML expressions verbatim.
  5883 
  5884 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5885 and 'text' support optional locale specification '(in loc)', which
  5886 specifies the default context for interpreting antiquotations.  For
  5887 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5888 
  5889 * Option 'locale=NAME' of antiquotations specifies an alternative
  5890 context interpreting the subsequent argument.  For example: @{thm
  5891 [locale=lattice] inf_assoc}.
  5892 
  5893 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5894 a proof context.
  5895 
  5896 * Proper output of antiquotations for theory commands involving a
  5897 proof context (such as 'locale' or 'theorem (in loc) ...').
  5898 
  5899 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5900 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5901 
  5902 * isatool usedir: new option -C (default true) controls whether option
  5903 -D should include a copy of the original document directory; -C false
  5904 prevents unwanted effects such as copying of administrative CVS data.
  5905 
  5906 
  5907 *** Pure ***
  5908 
  5909 * Considerably improved version of 'constdefs' command.  Now performs
  5910 automatic type-inference of declared constants; additional support for
  5911 local structure declarations (cf. locales and HOL records), see also
  5912 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5913 sequential dependencies of definitions within a single 'constdefs'
  5914 section; moreover, the declared name needs to be an identifier.  If
  5915 all fails, consider to fall back on 'consts' and 'defs' separately.
  5916 
  5917 * Improved indexed syntax and implicit structures.  First of all,
  5918 indexed syntax provides a notational device for subscripted
  5919 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5920 expressions.  Secondly, in a local context with structure
  5921 declarations, number indexes \<^sub>n or the empty index (default
  5922 number 1) refer to a certain fixed variable implicitly; option
  5923 show_structs controls printing of implicit structures.  Typical
  5924 applications of these concepts involve record types and locales.
  5925 
  5926 * New command 'no_syntax' removes grammar declarations (and
  5927 translations) resulting from the given syntax specification, which is
  5928 interpreted in the same manner as for the 'syntax' command.
  5929 
  5930 * 'Advanced' translation functions (parse_translation etc.) may depend
  5931 on the signature of the theory context being presently used for
  5932 parsing/printing, see also isar-ref manual.
  5933 
  5934 * Improved 'oracle' command provides a type-safe interface to turn an
  5935 ML expression of type theory -> T -> term into a primitive rule of
  5936 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5937 is already included here); see also FOL/ex/IffExample.thy;
  5938 INCOMPATIBILITY.
  5939 
  5940 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5941 before); "cI" is no longer bound, use "c.intro" instead.
  5942 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5943 axclasses vs. locales.
  5944 
  5945 * Improved internal renaming of symbolic identifiers -- attach primes
  5946 instead of base 26 numbers.
  5947 
  5948 * New flag show_question_marks controls printing of leading question
  5949 marks in schematic variable names.
  5950 
  5951 * In schematic variable names, *any* symbol following \<^isub> or
  5952 \<^isup> is now treated as part of the base name.  For example, the
  5953 following works without printing of awkward ".0" indexes:
  5954 
  5955   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5956     by simp
  5957 
  5958 * Inner syntax includes (*(*nested*) comments*).
  5959 
  5960 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5961 annotations as "(00...)".
  5962 
  5963 * Clear separation of logical types and nonterminals, where the latter
  5964 may only occur in 'syntax' specifications or type abbreviations.
  5965 Before that distinction was only partially implemented via type class
  5966 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5967 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5968 exotic syntax specifications may require further adaption
  5969 (e.g. Cube/Cube.thy).
  5970 
  5971 * Removed obsolete type class "logic", use the top sort {} instead.
  5972 Note that non-logical types should be declared as 'nonterminals'
  5973 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5974 specifications.
  5975 
  5976 * Attributes 'induct' and 'cases': type or set names may now be
  5977 locally fixed variables as well.
  5978 
  5979 * Simplifier: can now control the depth to which conditional rewriting
  5980 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5981 Limit.
  5982 
  5983 * Simplifier: simplification procedures may now take the current
  5984 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5985 interface), which is very useful for calling the Simplifier
  5986 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5987 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5988 low-level mk_simproc no longer applies Logic.varify internally, to
  5989 allow for use in a context of fixed variables.
  5990 
  5991 * thin_tac now works even if the assumption being deleted contains !!
  5992 or ==>.  More generally, erule now works even if the major premise of
  5993 the elimination rule contains !! or ==>.
  5994 
  5995 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5996 
  5997 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5998 from Pure, which contains all common declarations already.  Both
  5999 theories are defined via plain Isabelle/Isar .thy files.
  6000 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  6001 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  6002 use isatool fixcpure to adapt your theory and ML sources.
  6003 
  6004 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  6005 selections of theorems in named facts via index ranges.
  6006 
  6007 * 'print_theorems': in theory mode, really print the difference
  6008 wrt. the last state (works for interactive theory development only),
  6009 in proof mode print all local facts (cf. 'print_facts');
  6010 
  6011 * 'hide': option '(open)' hides only base names.
  6012 
  6013 * More efficient treatment of intermediate checkpoints in interactive
  6014 theory development.
  6015 
  6016 * Code generator is now invoked via code_module (incremental code
  6017 generation) and code_library (modular code generation, ML structures
  6018 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  6019 must be quoted when used as identifiers.
  6020 
  6021 * New 'value' command for reading, evaluating and printing terms using
  6022 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  6023 quoted when used as identifier.
  6024 
  6025 
  6026 *** Locales ***
  6027 
  6028 * New commands for the interpretation of locale expressions in
  6029 theories (1), locales (2) and proof contexts (3).  These generate
  6030 proof obligations from the expression specification.  After the
  6031 obligations have been discharged, theorems of the expression are added
  6032 to the theory, target locale or proof context.  The synopsis of the
  6033 commands is a follows:
  6034 
  6035   (1) interpretation expr inst
  6036   (2) interpretation target < expr
  6037   (3) interpret expr inst
  6038 
  6039 Interpretation in theories and proof contexts require a parameter
  6040 instantiation of terms from the current context.  This is applied to
  6041 specifications and theorems of the interpreted expression.
  6042 Interpretation in locales only permits parameter renaming through the
  6043 locale expression.  Interpretation is smart in that interpretations
  6044 that are active already do not occur in proof obligations, neither are
  6045 instantiated theorems stored in duplicate.  Use 'print_interps' to
  6046 inspect active interpretations of a particular locale.  For details,
  6047 see the Isar Reference manual.  Examples can be found in
  6048 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  6049 
  6050 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  6051 'interpret' instead.
  6052 
  6053 * New context element 'constrains' for adding type constraints to
  6054 parameters.
  6055 
  6056 * Context expressions: renaming of parameters with syntax
  6057 redeclaration.
  6058 
  6059 * Locale declaration: 'includes' disallowed.
  6060 
  6061 * Proper static binding of attribute syntax -- i.e. types / terms /
  6062 facts mentioned as arguments are always those of the locale definition
  6063 context, independently of the context of later invocations.  Moreover,
  6064 locale operations (renaming and type / term instantiation) are applied
  6065 to attribute arguments as expected.
  6066 
  6067 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  6068 actual attributes; rare situations may require Attrib.attribute to
  6069 embed those attributes into Attrib.src that lack concrete syntax.
  6070 Attribute implementations need to cooperate properly with the static
  6071 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  6072 Attrib.XXX_thm etc. already do the right thing without further
  6073 intervention.  Only unusual applications -- such as "where" or "of"
  6074 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  6075 on the context and the facts involved -- may have to assign parsed
  6076 values to argument tokens explicitly.
  6077 
  6078 * Changed parameter management in theorem generation for long goal
  6079 statements with 'includes'.  INCOMPATIBILITY: produces a different
  6080 theorem statement in rare situations.
  6081 
  6082 * Locale inspection command 'print_locale' omits notes elements.  Use
  6083 'print_locale!' to have them included in the output.
  6084 
  6085 
  6086 *** Provers ***
  6087 
  6088 * Provers/hypsubst.ML: improved version of the subst method, for
  6089 single-step rewriting: it now works in bound variable contexts. New is
  6090 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  6091 rewrite a different subterm than the original subst method, which is
  6092 still available as 'simplesubst'.
  6093 
  6094 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  6095 and quasi orders.
  6096 
  6097 * Provers/trancl.ML: new transitivity reasoner for transitive and
  6098 reflexive-transitive closure of relations.
  6099 
  6100 * Provers/blast.ML: new reference depth_limit to make blast's depth
  6101 limit (previously hard-coded with a value of 20) user-definable.
  6102 
  6103 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  6104 is peformed already.  Object-logics merely need to finish their
  6105 initial simpset configuration as before.  INCOMPATIBILITY.
  6106 
  6107 
  6108 *** HOL ***
  6109 
  6110 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  6111 
  6112   syntax (epsilon)
  6113     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  6114 
  6115 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  6116 and x-symbol; use option '-m epsilon' to get it actually printed.
  6117 Moreover, the mathematically important symbolic identifier \<epsilon>
  6118 becomes available as variable, constant etc.  INCOMPATIBILITY,
  6119 
  6120 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  6121 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  6122 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  6123 support corresponding Isar calculations.
  6124 
  6125 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  6126 instead of ":".
  6127 
  6128 * theory SetInterval: changed the syntax for open intervals:
  6129 
  6130   Old       New
  6131   {..n(}    {..<n}
  6132   {)n..}    {n<..}
  6133   {m..n(}   {m..<n}
  6134   {)m..n}   {m<..n}
  6135   {)m..n(}  {m<..<n}
  6136 
  6137 The old syntax is still supported but will disappear in the next
  6138 release.  For conversion use the following Emacs search and replace
  6139 patterns (these are not perfect but work quite well):
  6140 
  6141   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  6142   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  6143 
  6144 * Theory Commutative_Ring (in Library): method comm_ring for proving
  6145 equalities in commutative rings; method 'algebra' provides a generic
  6146 interface.
  6147 
  6148 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  6149 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  6150 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  6151 be a tuple pattern.
  6152 
  6153 Some new syntax forms are available:
  6154 
  6155   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  6156   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  6157   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  6158   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  6159 
  6160 The latter form "\<Sum>x < k. e" used to be based on a separate
  6161 function "Summation", which has been discontinued.
  6162 
  6163 * theory Finite_Set: in structured induction proofs, the insert case
  6164 is now 'case (insert x F)' instead of the old counterintuitive 'case
  6165 (insert F x)'.
  6166 
  6167 * The 'refute' command has been extended to support a much larger
  6168 fragment of HOL, including axiomatic type classes, constdefs and
  6169 typedefs, inductive datatypes and recursion.
  6170 
  6171 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  6172 Requires zChaff with proof generation to be installed.  See
  6173 HOL/ex/SAT_Examples.thy for examples.
  6174 
  6175 * Datatype induction via method 'induct' now preserves the name of the
  6176 induction variable. For example, when proving P(xs::'a list) by
  6177 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  6178 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  6179 in unstructured proof scripts.
  6180 
  6181 * Reworked implementation of records.  Improved scalability for
  6182 records with many fields, avoiding performance problems for type
  6183 inference. Records are no longer composed of nested field types, but
  6184 of nested extension types. Therefore the record type only grows linear
  6185 in the number of extensions and not in the number of fields.  The
  6186 top-level (users) view on records is preserved.  Potential
  6187 INCOMPATIBILITY only in strange cases, where the theory depends on the
  6188 old record representation. The type generated for a record is called
  6189 <record_name>_ext_type.
  6190 
  6191 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  6192 proofs triggered by a record definition or a simproc (if
  6193 quick_and_dirty is enabled).  Definitions of large records can take
  6194 quite long.
  6195 
  6196 New simproc record_upd_simproc for simplification of multiple record
  6197 updates enabled by default.  Moreover, trivial updates are also
  6198 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  6199 occasionally, since simplification is more powerful by default.
  6200 
  6201 * typedef: proper support for polymorphic sets, which contain extra
  6202 type-variables in the term.
  6203 
  6204 * Simplifier: automatically reasons about transitivity chains
  6205 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  6206 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  6207 old proofs break occasionally as simplification may now solve more
  6208 goals than previously.
  6209 
  6210 * Simplifier: converts x <= y into x = y if assumption y <= x is
  6211 present.  Works for all partial orders (class "order"), in particular
  6212 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  6213 just like y <= x.
  6214 
  6215 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  6216 bound variable or a constant then the let is unfolded.  Otherwise
  6217 first a is simplified to b, and then f b is simplified to g. If
  6218 possible we abstract b from g arriving at "let x = b in h x",
  6219 otherwise we unfold the let and arrive at g.  The simproc can be
  6220 enabled/disabled by the reference use_let_simproc.  Potential
  6221 INCOMPATIBILITY since simplification is more powerful by default.
  6222 
  6223 * Classical reasoning: the meson method now accepts theorems as arguments.
  6224 
  6225 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  6226 jobs to provide advice on the provability of subgoals.
  6227 
  6228 * Theory OrderedGroup and Ring_and_Field: various additions and
  6229 improvements to faciliate calculations involving equalities and
  6230 inequalities.
  6231 
  6232 The following theorems have been eliminated or modified
  6233 (INCOMPATIBILITY):
  6234 
  6235   abs_eq             now named abs_of_nonneg
  6236   abs_of_ge_0        now named abs_of_nonneg
  6237   abs_minus_eq       now named abs_of_nonpos
  6238   imp_abs_id         now named abs_of_nonneg
  6239   imp_abs_neg_id     now named abs_of_nonpos
  6240   mult_pos           now named mult_pos_pos
  6241   mult_pos_le        now named mult_nonneg_nonneg
  6242   mult_pos_neg_le    now named mult_nonneg_nonpos
  6243   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  6244   mult_neg           now named mult_neg_neg
  6245   mult_neg_le        now named mult_nonpos_nonpos
  6246 
  6247 * The following lemmas in Ring_and_Field have been added to the simplifier:
  6248      
  6249      zero_le_square
  6250      not_square_less_zero 
  6251 
  6252   The following lemmas have been deleted from Real/RealPow:
  6253   
  6254      realpow_zero_zero
  6255      realpow_two
  6256      realpow_less
  6257      zero_le_power
  6258      realpow_two_le
  6259      abs_realpow_two
  6260      realpow_two_abs     
  6261 
  6262 * Theory Parity: added rules for simplifying exponents.
  6263 
  6264 * Theory List:
  6265 
  6266 The following theorems have been eliminated or modified
  6267 (INCOMPATIBILITY):
  6268 
  6269   list_all_Nil       now named list_all.simps(1)
  6270   list_all_Cons      now named list_all.simps(2)
  6271   list_all_conv      now named list_all_iff
  6272   set_mem_eq         now named mem_iff
  6273 
  6274 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  6275 asymptotic "big O" calculations.  See the notes in BigO.thy.
  6276 
  6277 
  6278 *** HOL-Complex ***
  6279 
  6280 * Theory RealDef: better support for embedding natural numbers and
  6281 integers in the reals.
  6282 
  6283 The following theorems have been eliminated or modified
  6284 (INCOMPATIBILITY):
  6285 
  6286   exp_ge_add_one_self  now requires no hypotheses
  6287   real_of_int_add      reversed direction of equality (use [symmetric])
  6288   real_of_int_minus    reversed direction of equality (use [symmetric])
  6289   real_of_int_diff     reversed direction of equality (use [symmetric])
  6290   real_of_int_mult     reversed direction of equality (use [symmetric])
  6291 
  6292 * Theory RComplete: expanded support for floor and ceiling functions.
  6293 
  6294 * Theory Ln is new, with properties of the natural logarithm
  6295 
  6296 * Hyperreal: There is a new type constructor "star" for making
  6297 nonstandard types.  The old type names are now type synonyms:
  6298 
  6299   hypreal = real star
  6300   hypnat = nat star
  6301   hcomplex = complex star
  6302 
  6303 * Hyperreal: Many groups of similarly-defined constants have been
  6304 replaced by polymorphic versions (INCOMPATIBILITY):
  6305 
  6306   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  6307 
  6308   starset      <-- starsetNat, starsetC
  6309   *s*          <-- *sNat*, *sc*
  6310   starset_n    <-- starsetNat_n, starsetC_n
  6311   *sn*         <-- *sNatn*, *scn*
  6312   InternalSets <-- InternalNatSets, InternalCSets
  6313 
  6314   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  6315   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  6316   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  6317   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  6318   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  6319 
  6320 * Hyperreal: Many type-specific theorems have been removed in favor of
  6321 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  6322 
  6323   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  6324   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  6325   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  6326   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  6327   right_minus <-- hypreal_add_minus
  6328   left_minus <-- {hypreal,hcomplex}_add_minus_left
  6329   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  6330   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  6331   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  6332   mult_1_right <-- hcomplex_mult_one_right
  6333   mult_zero_left <-- hcomplex_mult_zero_left
  6334   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  6335   right_distrib <-- hypnat_add_mult_distrib2
  6336   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  6337   right_inverse <-- hypreal_mult_inverse
  6338   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  6339   order_refl <-- {hypreal,hypnat}_le_refl
  6340   order_trans <-- {hypreal,hypnat}_le_trans
  6341   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  6342   order_less_le <-- {hypreal,hypnat}_less_le
  6343   linorder_linear <-- {hypreal,hypnat}_le_linear
  6344   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  6345   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  6346   add_nonneg_nonneg <-- hypreal_le_add_order
  6347 
  6348 * Hyperreal: Separate theorems having to do with type-specific
  6349 versions of constants have been merged into theorems that apply to the
  6350 new polymorphic constants (INCOMPATIBILITY):
  6351 
  6352   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  6353   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  6354   STAR_Un <-- {STAR,NatStar,STARC}_Un
  6355   STAR_Int <-- {STAR,NatStar,STARC}_Int
  6356   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  6357   STAR_subset <-- {STAR,NatStar,STARC}_subset
  6358   STAR_mem <-- {STAR,NatStar,STARC}_mem
  6359   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  6360   STAR_diff <-- {STAR,STARC}_diff
  6361   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  6362     STARC_hcomplex_of_complex}_image_subset
  6363   starset_n_Un <-- starset{Nat,C}_n_Un
  6364   starset_n_Int <-- starset{Nat,C}_n_Int
  6365   starset_n_Compl <-- starset{Nat,C}_n_Compl
  6366   starset_n_diff <-- starset{Nat,C}_n_diff
  6367   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  6368   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  6369   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  6370   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  6371   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  6372   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  6373   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  6374   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  6375   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  6376   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  6377   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  6378   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  6379   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  6380   starfun_diff <-- starfun{C,RC,CR}_diff
  6381   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  6382   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  6383   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  6384   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  6385   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  6386   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  6387   starfun_Id <-- starfunC_Id
  6388   starfun_approx <-- starfun{Nat,CR}_approx
  6389   starfun_capprox <-- starfun{C,RC}_capprox
  6390   starfun_abs <-- starfunNat_rabs
  6391   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  6392   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  6393   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  6394   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  6395   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  6396   starfun_add_approx <-- starfunCR_add_approx
  6397   starfun_inverse_inverse <-- starfunC_inverse_inverse
  6398   starfun_divide <-- starfun{C,CR,RC}_divide
  6399   starfun_n <-- starfun{Nat,C}_n
  6400   starfun_n_mult <-- starfun{Nat,C}_n_mult
  6401   starfun_n_add <-- starfun{Nat,C}_n_add
  6402   starfun_n_add_minus <-- starfunNat_n_add_minus
  6403   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  6404   starfun_n_minus <-- starfun{Nat,C}_n_minus
  6405   starfun_n_eq <-- starfun{Nat,C}_n_eq
  6406 
  6407   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  6408   star_n_minus <-- {hypreal,hcomplex}_minus
  6409   star_n_diff <-- {hypreal,hcomplex}_diff
  6410   star_n_mult <-- {hypreal,hcomplex}_mult
  6411   star_n_inverse <-- {hypreal,hcomplex}_inverse
  6412   star_n_le <-- {hypreal,hypnat}_le
  6413   star_n_less <-- {hypreal,hypnat}_less
  6414   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  6415   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  6416   star_n_abs <-- hypreal_hrabs
  6417   star_n_divide <-- hcomplex_divide
  6418 
  6419   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  6420   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  6421   star_of_diff <-- hypreal_of_real_diff
  6422   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  6423   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  6424   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  6425   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  6426   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  6427   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  6428   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  6429   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  6430   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  6431   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  6432   star_of_number_of <-- {hypreal,hcomplex}_number_of
  6433   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  6434   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  6435   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  6436   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  6437   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  6438   star_of_power <-- hypreal_of_real_power
  6439   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  6440 
  6441 * Hyperreal: new method "transfer" that implements the transfer
  6442 principle of nonstandard analysis. With a subgoal that mentions
  6443 nonstandard types like "'a star", the command "apply transfer"
  6444 replaces it with an equivalent one that mentions only standard types.
  6445 To be successful, all free variables must have standard types; non-
  6446 standard variables must have explicit universal quantifiers.
  6447 
  6448 * Hyperreal: A theory of Taylor series.
  6449 
  6450 
  6451 *** HOLCF ***
  6452 
  6453 * Discontinued special version of 'constdefs' (which used to support
  6454 continuous functions) in favor of the general Pure one with full
  6455 type-inference.
  6456 
  6457 * New simplification procedure for solving continuity conditions; it
  6458 is much faster on terms with many nested lambda abstractions (cubic
  6459 instead of exponential time).
  6460 
  6461 * New syntax for domain package: selector names are now optional.
  6462 Parentheses should be omitted unless argument is lazy, for example:
  6463 
  6464   domain 'a stream = cons "'a" (lazy "'a stream")
  6465 
  6466 * New command 'fixrec' for defining recursive functions with pattern
  6467 matching; defining multiple functions with mutual recursion is also
  6468 supported.  Patterns may include the constants cpair, spair, up, sinl,
  6469 sinr, or any data constructor defined by the domain package. The given
  6470 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  6471 syntax and examples.
  6472 
  6473 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  6474 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  6475 but the proof obligation additionally includes an admissibility
  6476 requirement. The packages generate instances of class cpo or pcpo,
  6477 with continuity and strictness theorems for Rep and Abs.
  6478 
  6479 * HOLCF: Many theorems have been renamed according to a more standard naming
  6480 scheme (INCOMPATIBILITY):
  6481 
  6482   foo_inject:  "foo$x = foo$y ==> x = y"
  6483   foo_eq:      "(foo$x = foo$y) = (x = y)"
  6484   foo_less:    "(foo$x << foo$y) = (x << y)"
  6485   foo_strict:  "foo$UU = UU"
  6486   foo_defined: "... ==> foo$x ~= UU"
  6487   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  6488 
  6489 
  6490 *** ZF ***
  6491 
  6492 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  6493 including the First Isomorphism Theorem (on quotienting by the kernel
  6494 of a homomorphism).
  6495 
  6496 * ZF/Simplifier: install second copy of type solver that actually
  6497 makes use of TC rules declared to Isar proof contexts (or locales);
  6498 the old version is still required for ML proof scripts.
  6499 
  6500 
  6501 *** Cube ***
  6502 
  6503 * Converted to Isar theory format; use locales instead of axiomatic
  6504 theories.
  6505 
  6506 
  6507 *** ML ***
  6508 
  6509 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6510 for ||>, ||>>, |>>,
  6511 
  6512 * Pure/library.ML no longer defines its own option datatype, but uses
  6513 that of the SML basis, which has constructors NONE and SOME instead of
  6514 None and Some, as well as exception Option.Option instead of OPTION.
  6515 The functions the, if_none, is_some, is_none have been adapted
  6516 accordingly, while Option.map replaces apsome.
  6517 
  6518 * Pure/library.ML: the exception LIST has been given up in favour of
  6519 the standard exceptions Empty and Subscript, as well as
  6520 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6521 superceded by the standard hd and tl functions etc.
  6522 
  6523 A number of basic list functions are no longer exported to the ML
  6524 toplevel, as they are variants of predefined functions.  The following
  6525 suggests how one can translate existing code:
  6526 
  6527     rev_append xs ys = List.revAppend (xs, ys)
  6528     nth_elem (i, xs) = List.nth (xs, i)
  6529     last_elem xs = List.last xs
  6530     flat xss = List.concat xss
  6531     seq fs = List.app fs
  6532     partition P xs = List.partition P xs
  6533     mapfilter f xs = List.mapPartial f xs
  6534 
  6535 * Pure/library.ML: several combinators for linear functional
  6536 transformations, notably reverse application and composition:
  6537 
  6538   x |> f                f #> g
  6539   (x, y) |-> f          f #-> g
  6540 
  6541 * Pure/library.ML: introduced/changed precedence of infix operators:
  6542 
  6543   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6544   infix 2 ?;
  6545   infix 3 o oo ooo oooo;
  6546   infix 4 ~~ upto downto;
  6547 
  6548 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6549 infix operators.
  6550 
  6551 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6552 fold_map support linear functional transformations and nesting.  For
  6553 example:
  6554 
  6555   fold f [x1, ..., xN] y =
  6556     y |> f x1 |> ... |> f xN
  6557 
  6558   (fold o fold) f [xs1, ..., xsN] y =
  6559     y |> fold f xs1 |> ... |> fold f xsN
  6560 
  6561   fold f [x1, ..., xN] =
  6562     f x1 #> ... #> f xN
  6563 
  6564   (fold o fold) f [xs1, ..., xsN] =
  6565     fold f xs1 #> ... #> fold f xsN
  6566 
  6567 * Pure/library.ML: the following selectors on type 'a option are
  6568 available:
  6569 
  6570   the:               'a option -> 'a  (*partial*)
  6571   these:             'a option -> 'a  where 'a = 'b list
  6572   the_default: 'a -> 'a option -> 'a
  6573   the_list:          'a option -> 'a list
  6574 
  6575 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6576 basic operations for association lists, following natural argument
  6577 order; moreover the explicit equality predicate passed here avoids
  6578 potentially expensive polymorphic runtime equality checks.
  6579 The old functions may be expressed as follows:
  6580 
  6581   assoc = uncurry (AList.lookup (op =))
  6582   assocs = these oo AList.lookup (op =)
  6583   overwrite = uncurry (AList.update (op =)) o swap
  6584 
  6585 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6586 
  6587   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6588   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6589 
  6590 replacing make_keylist and keyfilter (occassionally used)
  6591 Naive rewrites:
  6592 
  6593   make_keylist = AList.make
  6594   keyfilter = AList.find (op =)
  6595 
  6596 * eq_fst and eq_snd now take explicit equality parameter, thus
  6597   avoiding eqtypes. Naive rewrites:
  6598 
  6599     eq_fst = eq_fst (op =)
  6600     eq_snd = eq_snd (op =)
  6601 
  6602 * Removed deprecated apl and apr (rarely used).
  6603   Naive rewrites:
  6604 
  6605     apl (n, op) =>>= curry op n
  6606     apr (op, m) =>>= fn n => op (n, m)
  6607 
  6608 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6609 provides a reasonably efficient light-weight implementation of sets as
  6610 lists.
  6611 
  6612 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6613 few new operations; existing lookup and update are now curried to
  6614 follow natural argument order (for use with fold etc.);
  6615 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6616 
  6617 * Pure/General: output via the Isabelle channels of
  6618 writeln/warning/error etc. is now passed through Output.output, with a
  6619 hook for arbitrary transformations depending on the print_mode
  6620 (cf. Output.add_mode -- the first active mode that provides a output
  6621 function wins).  Already formatted output may be embedded into further
  6622 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6623 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6624 accommodate easy composition of diagnostic messages etc.  Programmers
  6625 rarely need to care about Output.output or Output.raw at all, with
  6626 some notable exceptions: Output.output is required when bypassing the
  6627 standard channels (writeln etc.), or in token translations to produce
  6628 properly formatted results; Output.raw is required when capturing
  6629 already output material that will eventually be presented to the user
  6630 a second time.  For the default print mode, both Output.output and
  6631 Output.raw have no effect.
  6632 
  6633 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6634 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6635 cumulative results are displayed at the end of a batch session.
  6636 
  6637 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6638 replaced by File.platform_path and File.shell_path (with appropriate
  6639 hooks).  This provides a clean interface for unusual systems where the
  6640 internal and external process view of file names are different.
  6641 
  6642 * Pure: more efficient orders for basic syntactic entities: added
  6643 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6644 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6645 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6646 orders now -- potential INCOMPATIBILITY for code that depends on a
  6647 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6648 Library.sort_strings on result).
  6649 
  6650 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6651 fold_types traverse types/terms from left to right, observing natural
  6652 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6653 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6654 
  6655 * Pure: name spaces have been refined, with significant changes of the
  6656 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6657 to extern(_table).  The plain name entry path is superceded by a
  6658 general 'naming' context, which also includes the 'policy' to produce
  6659 a fully qualified name and external accesses of a fully qualified
  6660 name; NameSpace.extend is superceded by context dependent
  6661 Sign.declare_name.  Several theory and proof context operations modify
  6662 the naming context.  Especially note Theory.restore_naming and
  6663 ProofContext.restore_naming to get back to a sane state; note that
  6664 Theory.add_path is no longer sufficient to recover from
  6665 Theory.absolute_path in particular.
  6666 
  6667 * Pure: new flags short_names (default false) and unique_names
  6668 (default true) for controlling output of qualified names.  If
  6669 short_names is set, names are printed unqualified.  If unique_names is
  6670 reset, the name prefix is reduced to the minimum required to achieve
  6671 the original result when interning again, even if there is an overlap
  6672 with earlier declarations.
  6673 
  6674 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6675 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6676 (useful for printing error messages).  INCOMPATIBILITY.
  6677 
  6678 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6679 Theory.theory are now identified, referring to the universal
  6680 Context.theory (see Pure/context.ML).  Actual signature and theory
  6681 content is managed as theory data.  The old code and interfaces were
  6682 spread over many files and structures; the new arrangement introduces
  6683 considerable INCOMPATIBILITY to gain more clarity:
  6684 
  6685   Context -- theory management operations (name, identity, inclusion,
  6686     parents, ancestors, merge, etc.), plus generic theory data;
  6687 
  6688   Sign -- logical signature and syntax operations (declaring consts,
  6689     types, etc.), plus certify/read for common entities;
  6690 
  6691   Theory -- logical theory operations (stating axioms, definitions,
  6692     oracles), plus a copy of logical signature operations (consts,
  6693     types, etc.); also a few basic management operations (Theory.copy,
  6694     Theory.merge, etc.)
  6695 
  6696 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6697 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6698 for convenience -- they merely return the theory.
  6699 
  6700 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6701 
  6702 * Pure: the Isar proof context type is already defined early in Pure
  6703 as Context.proof (note that ProofContext.context and Proof.context are
  6704 aliases, where the latter is the preferred name).  This enables other
  6705 Isabelle components to refer to that type even before Isar is present.
  6706 
  6707 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6708 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6709 any of these kinds.  For example, Sign.intern typeK is now
  6710 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6711 Theory.hide_types.  Also note that former
  6712 Theory.hide_classes/types/consts are now
  6713 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6714 internalize their arguments!  INCOMPATIBILITY.
  6715 
  6716 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6717 datatype thmref (with constructors Name and NameSelection) instead of
  6718 plain string -- INCOMPATIBILITY;
  6719 
  6720 * Pure: cases produced by proof methods specify options, where NONE
  6721 means to remove case bindings -- INCOMPATIBILITY in
  6722 (RAW_)METHOD_CASES.
  6723 
  6724 * Pure: the following operations retrieve axioms or theorems from a
  6725 theory node or theory hierarchy, respectively:
  6726 
  6727   Theory.axioms_of: theory -> (string * term) list
  6728   Theory.all_axioms_of: theory -> (string * term) list
  6729   PureThy.thms_of: theory -> (string * thm) list
  6730   PureThy.all_thms_of: theory -> (string * thm) list
  6731 
  6732 * Pure: print_tac now outputs the goal through the trace channel.
  6733 
  6734 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6735 Reference Toplevel.debug (default false) controls detailed printing
  6736 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6737 controls execution profiling -- set to 1 for time and 2 for space
  6738 (both increase the runtime).
  6739 
  6740 * Isar session: The initial use of ROOT.ML is now always timed,
  6741 i.e. the log will show the actual process times, in contrast to the
  6742 elapsed wall-clock time that the outer shell wrapper produces.
  6743 
  6744 * Simplifier: improved handling of bound variables (nameless
  6745 representation, avoid allocating new strings).  Simprocs that invoke
  6746 the Simplifier recursively should use Simplifier.inherit_bounds to
  6747 avoid local name clashes.  Failure to do so produces warnings
  6748 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6749 for further details.
  6750 
  6751 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6752 bindings for all theorems stored within a given theory; this may help
  6753 in porting non-Isar theories to Isar ones, while keeping ML proof
  6754 scripts for the time being.
  6755 
  6756 * ML operator HTML.with_charset specifies the charset begin used for
  6757 generated HTML files.  For example:
  6758 
  6759   HTML.with_charset "utf-8" use_thy "Hebrew";
  6760   HTML.with_charset "utf-8" use_thy "Chinese";
  6761 
  6762 
  6763 *** System ***
  6764 
  6765 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6766 isabelle, isatool etc.).
  6767 
  6768 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6769 isatool doc, isatool mkdir, display_drafts etc.).
  6770 
  6771 * isatool usedir: option -f allows specification of the ML file to be
  6772 used by Isabelle; default is ROOT.ML.
  6773 
  6774 * New isatool version outputs the version identifier of the Isabelle
  6775 distribution being used.
  6776 
  6777 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6778 (containing Boolean satisfiability problems) into Isabelle/HOL
  6779 theories.
  6780 
  6781 
  6782 
  6783 New in Isabelle2004 (April 2004)
  6784 --------------------------------
  6785 
  6786 *** General ***
  6787 
  6788 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6789   Replaces linorder.ML.
  6790 
  6791 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6792   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6793   (\<a>...\<z>), are now considered normal letters, and can therefore
  6794   be used anywhere where an ASCII letter (a...zA...Z) has until
  6795   now. COMPATIBILITY: This obviously changes the parsing of some
  6796   terms, especially where a symbol has been used as a binder, say
  6797   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6798   as an identifier.  Fix it by inserting a space around former
  6799   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6800   existing theory and ML files.
  6801 
  6802 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6803 
  6804 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6805   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6806   a normal (but invisible) letter. For multiple letter subscripts repeat
  6807   \<^isub> like this: x\<^isub>1\<^isub>2.
  6808 
  6809 * Pure: There are now sub-/superscripts that can span more than one
  6810   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6811   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6812   superscript. The new control characters are not identifier parts.
  6813 
  6814 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6815   content of "..." to the latex file instead of \isacntrl... . The "..."
  6816   may consist of any printable characters excluding the end bracket >.
  6817 
  6818 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6819   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6820   declare constants "final", which prevents their being given a definition
  6821   later.  It is useful for constants whose behaviour is fixed axiomatically
  6822   rather than definitionally, such as the meta-logic connectives.
  6823 
  6824 * Pure: 'instance' now handles general arities with general sorts
  6825   (i.e. intersections of classes),
  6826 
  6827 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6828   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6829   It can be changed to alter the colors/layout of generated pages.
  6830 
  6831 
  6832 *** Isar ***
  6833 
  6834 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6835   cut_tac, subgoal_tac and thin_tac:
  6836   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6837     locales are no longer forced to write Isar proof scripts.
  6838     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6839     emulations.
  6840   - INCOMPATIBILITY: names of variables to be instantiated may no
  6841     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6842     This is consistent with the instantiation attribute "where".
  6843 
  6844 * Attributes "where" and "of":
  6845   - Now take type variables of instantiated theorem into account when reading
  6846     the instantiation string.  This fixes a bug that caused instantiated
  6847     theorems to have too special types in some circumstances.
  6848   - "where" permits explicit instantiations of type variables.
  6849 
  6850 * Calculation commands "moreover" and "also" no longer interfere with
  6851   current facts ("this"), admitting arbitrary combinations with "then"
  6852   and derived forms.
  6853 
  6854 * Locales:
  6855   - Goal statements involving the context element "includes" no longer
  6856     generate theorems with internal delta predicates (those ending on
  6857     "_axioms") in the premise.
  6858     Resolve particular premise with <locale>.intro to obtain old form.
  6859   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6860     specification and "includes" elements in goal statement.
  6861   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6862     [intro?] and [elim?] (respectively) by default.
  6863   - Experimental command for instantiation of locales in proof contexts:
  6864         instantiate <label>[<attrs>]: <loc>
  6865     Instantiates locale <loc> and adds all its theorems to the current context
  6866     taking into account their attributes.  Label and attrs are optional
  6867     modifiers, like in theorem declarations.  If present, names of
  6868     instantiated theorems are qualified with <label>, and the attributes
  6869     <attrs> are applied after any attributes these theorems might have already.
  6870       If the locale has assumptions, a chained fact of the form
  6871     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6872     are derived.  The command does not support old-style locales declared
  6873     with "locale (open)".
  6874       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6875 
  6876 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6877   (Isar) contexts.
  6878 
  6879 
  6880 *** HOL ***
  6881 
  6882 * Proof import: new image HOL4 contains the imported library from
  6883   the HOL4 system with about 2500 theorems. It is imported by
  6884   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6885   can be used like any other Isabelle image.  See
  6886   HOL/Import/HOL/README for more information.
  6887 
  6888 * Simplifier:
  6889   - Much improved handling of linear and partial orders.
  6890     Reasoners for linear and partial orders are set up for type classes
  6891     "linorder" and "order" respectively, and are added to the default simpset
  6892     as solvers.  This means that the simplifier can build transitivity chains
  6893     to solve goals from the assumptions.
  6894   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6895     of blast or auto after simplification become unnecessary because the goal
  6896     is solved by simplification already.
  6897 
  6898 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6899     all proved in axiomatic type classes for semirings, rings and fields.
  6900 
  6901 * Numerics:
  6902   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6903     now formalized using the Ring_and_Field theory mentioned above.
  6904   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6905     than before, because now they are set up once in a generic manner.
  6906   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6907     Look for the general versions in Ring_and_Field (and Power if they concern
  6908     exponentiation).
  6909 
  6910 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6911 
  6912 * Records:
  6913   - Record types are now by default printed with their type abbreviation
  6914     instead of the list of all field types. This can be configured via
  6915     the reference "print_record_type_abbr".
  6916   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6917     (not enabled by default).
  6918   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6919     EX x. x = sel r to True (not enabled by default).
  6920   - Tactic "record_split_simp_tac" to split and simplify records added.
  6921 
  6922 * 'specification' command added, allowing for definition by
  6923   specification.  There is also an 'ax_specification' command that
  6924   introduces the new constants axiomatically.
  6925 
  6926 * arith(_tac) is now able to generate counterexamples for reals as well.
  6927 
  6928 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6929 
  6930 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6931   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6932 
  6933 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6934   matrix theory to linear programming.
  6935 
  6936 * Unions and Intersections:
  6937   The latex output syntax of UN and INT has been changed
  6938   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6939   i.e. the index formulae has become a subscript.
  6940   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6941 
  6942 * Unions and Intersections over Intervals:
  6943   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6944   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6945   like in normal math, and corresponding versions for < and for intersection.
  6946 
  6947 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6948   lexicographic dictonary ordering has been added as "lexord".
  6949 
  6950 * ML: the legacy theory structures Int and List have been removed. They had
  6951   conflicted with ML Basis Library structures having the same names.
  6952 
  6953 * 'refute' command added to search for (finite) countermodels.  Only works
  6954   for a fragment of HOL.  The installation of an external SAT solver is
  6955   highly recommended.  See "HOL/Refute.thy" for details.
  6956 
  6957 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6958   formulae under an assignment of free variables to random values.
  6959   In contrast to 'refute', it can deal with inductive datatypes,
  6960   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6961   for examples.
  6962 
  6963 
  6964 *** HOLCF ***
  6965 
  6966 * Streams now come with concatenation and are part of the HOLCF image
  6967 
  6968 
  6969 
  6970 New in Isabelle2003 (May 2003)
  6971 ------------------------------
  6972 
  6973 *** General ***
  6974 
  6975 * Provers/simplifier:
  6976 
  6977   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6978     Assumptions are now subject to complete mutual simplification,
  6979     not just from left to right. The simplifier now preserves
  6980     the order of assumptions.
  6981 
  6982     Potential INCOMPATIBILITY:
  6983 
  6984     -- simp sometimes diverges where the old version did
  6985        not, e.g. invoking simp on the goal
  6986 
  6987         [| P (f x); y = x; f x = f y |] ==> Q
  6988 
  6989        now gives rise to the infinite reduction sequence
  6990 
  6991         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6992 
  6993        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6994        kind of problem.
  6995 
  6996     -- Tactics combining classical reasoner and simplification (such as auto)
  6997        are also affected by this change, because many of them rely on
  6998        simp. They may sometimes diverge as well or yield a different numbers
  6999        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  7000        in case of problems. Sometimes subsequent calls to the classical
  7001        reasoner will fail because a preceeding call to the simplifier too
  7002        eagerly simplified the goal, e.g. deleted redundant premises.
  7003 
  7004   - The simplifier trace now shows the names of the applied rewrite rules
  7005 
  7006   - You can limit the number of recursive invocations of the simplifier
  7007     during conditional rewriting (where the simplifie tries to solve the
  7008     conditions before applying the rewrite rule):
  7009     ML "simp_depth_limit := n"
  7010     where n is an integer. Thus you can force termination where previously
  7011     the simplifier would diverge.
  7012 
  7013   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  7014 
  7015   - No longer aborts on failed congruence proof.  Instead, the
  7016     congruence is ignored.
  7017 
  7018 * Pure: New generic framework for extracting programs from constructive
  7019   proofs. See HOL/Extraction.thy for an example instantiation, as well
  7020   as HOL/Extraction for some case studies.
  7021 
  7022 * Pure: The main goal of the proof state is no longer shown by default, only
  7023 the subgoals. This behaviour is controlled by a new flag.
  7024    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  7025 (ML: Proof.show_main_goal).
  7026 
  7027 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  7028 rules whose conclusion matches subgoal 1:
  7029       PG menu: Isabelle/Isar -> Show me -> matching rules
  7030 The rules are ordered by how closely they match the subgoal.
  7031 In particular, rules that solve a subgoal outright are displayed first
  7032 (or rather last, the way they are printed).
  7033 (ML: ProofGeneral.print_intros())
  7034 
  7035 * Pure: New flag trace_unify_fail causes unification to print
  7036 diagnostic information (PG: in trace buffer) when it fails. This is
  7037 useful for figuring out why single step proofs like rule, erule or
  7038 assumption failed.
  7039 
  7040 * Pure: Locale specifications now produce predicate definitions
  7041 according to the body of text (covering assumptions modulo local
  7042 definitions); predicate "loc_axioms" covers newly introduced text,
  7043 while "loc" is cumulative wrt. all included locale expressions; the
  7044 latter view is presented only on export into the global theory
  7045 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  7046 on the old view without predicates;
  7047 
  7048 * Pure: predefined locales "var" and "struct" are useful for sharing
  7049 parameters (as in CASL, for example); just specify something like
  7050 ``var x + var y + struct M'' as import;
  7051 
  7052 * Pure: improved thms_containing: proper indexing of facts instead of
  7053 raw theorems; check validity of results wrt. current name space;
  7054 include local facts of proof configuration (also covers active
  7055 locales), cover fixed variables in index; may use "_" in term
  7056 specification; an optional limit for the number of printed facts may
  7057 be given (the default is 40);
  7058 
  7059 * Pure: disallow duplicate fact bindings within new-style theory files
  7060 (batch-mode only);
  7061 
  7062 * Provers: improved induct method: assumptions introduced by case
  7063 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  7064 the goal statement); "foo" still refers to all facts collectively;
  7065 
  7066 * Provers: the function blast.overloaded has been removed: all constants
  7067 are regarded as potentially overloaded, which improves robustness in exchange
  7068 for slight decrease in efficiency;
  7069 
  7070 * Provers/linorder: New generic prover for transitivity reasoning over
  7071 linear orders.  Note: this prover is not efficient!
  7072 
  7073 * Isar: preview of problems to finish 'show' now produce an error
  7074 rather than just a warning (in interactive mode);
  7075 
  7076 
  7077 *** HOL ***
  7078 
  7079 * arith(_tac)
  7080 
  7081  - Produces a counter example if it cannot prove a goal.
  7082    Note that the counter example may be spurious if the goal is not a formula
  7083    of quantifier-free linear arithmetic.
  7084    In ProofGeneral the counter example appears in the trace buffer.
  7085 
  7086  - Knows about div k and mod k where k is a numeral of type nat or int.
  7087 
  7088  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  7089    linear arithmetic fails. This takes account of quantifiers and divisibility.
  7090    Presburger arithmetic can also be called explicitly via presburger(_tac).
  7091 
  7092 * simp's arithmetic capabilities have been enhanced a bit: it now
  7093 takes ~= in premises into account (by performing a case split);
  7094 
  7095 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  7096 are distributed over a sum of terms;
  7097 
  7098 * New tactic "trans_tac" and method "trans" instantiate
  7099 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  7100 "<=", "<" and "=").
  7101 
  7102 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  7103 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  7104 
  7105 * 'typedef' command has new option "open" to suppress the set
  7106 definition;
  7107 
  7108 * functions Min and Max on finite sets have been introduced (theory
  7109 Finite_Set);
  7110 
  7111 * attribute [symmetric] now works for relations as well; it turns
  7112 (x,y) : R^-1 into (y,x) : R, and vice versa;
  7113 
  7114 * induct over a !!-quantified statement (say !!x1..xn):
  7115   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  7116 
  7117 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  7118 %x. None. Warning: empty_def now refers to the previously hidden definition
  7119 of the empty set.
  7120 
  7121 * Algebra: formalization of classical algebra.  Intended as base for
  7122 any algebraic development in Isabelle.  Currently covers group theory
  7123 (up to Sylow's theorem) and ring theory (Universal Property of
  7124 Univariate Polynomials).  Contributions welcome;
  7125 
  7126 * GroupTheory: deleted, since its material has been moved to Algebra;
  7127 
  7128 * Complex: new directory of the complex numbers with numeric constants,
  7129 nonstandard complex numbers, and some complex analysis, standard and
  7130 nonstandard (Jacques Fleuriot);
  7131 
  7132 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  7133 
  7134 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  7135 Fleuriot);
  7136 
  7137 * Real/HahnBanach: updated and adapted to locales;
  7138 
  7139 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  7140 Gray and Kramer);
  7141 
  7142 * UNITY: added the Meier-Sanders theory of progress sets;
  7143 
  7144 * MicroJava: bytecode verifier and lightweight bytecode verifier
  7145 as abstract algorithms, instantiated to the JVM;
  7146 
  7147 * Bali: Java source language formalization. Type system, operational
  7148 semantics, axiomatic semantics. Supported language features:
  7149 classes, interfaces, objects,virtual methods, static methods,
  7150 static/instance fields, arrays, access modifiers, definite
  7151 assignment, exceptions.
  7152 
  7153 
  7154 *** ZF ***
  7155 
  7156 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  7157 universe, etc.);
  7158 
  7159 * Main ZF: virtually all theories converted to new-style format;
  7160 
  7161 
  7162 *** ML ***
  7163 
  7164 * Pure: Tactic.prove provides sane interface for internal proofs;
  7165 omits the infamous "standard" operation, so this is more appropriate
  7166 than prove_goalw_cterm in many situations (e.g. in simprocs);
  7167 
  7168 * Pure: improved error reporting of simprocs;
  7169 
  7170 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  7171 up simprocs;
  7172 
  7173 
  7174 *** Document preparation ***
  7175 
  7176 * uses \par instead of \\ for line breaks in theory text. This may
  7177 shift some page breaks in large documents. To get the old behaviour
  7178 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  7179 
  7180 * minimized dependencies of isabelle.sty and isabellesym.sty on
  7181 other packages
  7182 
  7183 * \<euro> now needs package babel/greek instead of marvosym (which
  7184 broke \Rightarrow)
  7185 
  7186 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  7187 textcomp package)
  7188 
  7189 
  7190 
  7191 New in Isabelle2002 (March 2002)
  7192 --------------------------------
  7193 
  7194 *** Document preparation ***
  7195 
  7196 * greatly simplified document preparation setup, including more
  7197 graceful interpretation of isatool usedir -i/-d/-D options, and more
  7198 instructive isatool mkdir; users should basically be able to get
  7199 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  7200 users may run a separate document processing stage manually like this:
  7201 "isatool usedir -D output HOL Test && isatool document Test/output";
  7202 
  7203 * theory dependency graph may now be incorporated into documents;
  7204 isatool usedir -g true will produce session_graph.eps/.pdf for use
  7205 with \includegraphics of LaTeX;
  7206 
  7207 * proper spacing of consecutive markup elements, especially text
  7208 blocks after section headings;
  7209 
  7210 * support bold style (for single symbols only), input syntax is like
  7211 this: "\<^bold>\<alpha>" or "\<^bold>A";
  7212 
  7213 * \<bullet> is now output as bold \cdot by default, which looks much
  7214 better in printed text;
  7215 
  7216 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  7217 note that these symbols are currently unavailable in Proof General /
  7218 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  7219 
  7220 * isatool latex no longer depends on changed TEXINPUTS, instead
  7221 isatool document copies the Isabelle style files to the target
  7222 location;
  7223 
  7224 
  7225 *** Isar ***
  7226 
  7227 * Pure/Provers: improved proof by cases and induction;
  7228   - 'case' command admits impromptu naming of parameters (such as
  7229     "case (Suc n)");
  7230   - 'induct' method divinates rule instantiation from the inductive
  7231     claim; no longer requires excessive ?P bindings for proper
  7232     instantiation of cases;
  7233   - 'induct' method properly enumerates all possibilities of set/type
  7234     rules; as a consequence facts may be also passed through *type*
  7235     rules without further ado;
  7236   - 'induct' method now derives symbolic cases from the *rulified*
  7237     rule (before it used to rulify cases stemming from the internal
  7238     atomized version); this means that the context of a non-atomic
  7239     statement becomes is included in the hypothesis, avoiding the
  7240     slightly cumbersome show "PROP ?case" form;
  7241   - 'induct' may now use elim-style induction rules without chaining
  7242     facts, using ``missing'' premises from the goal state; this allows
  7243     rules stemming from inductive sets to be applied in unstructured
  7244     scripts, while still benefitting from proper handling of non-atomic
  7245     statements; NB: major inductive premises need to be put first, all
  7246     the rest of the goal is passed through the induction;
  7247   - 'induct' proper support for mutual induction involving non-atomic
  7248     rule statements (uses the new concept of simultaneous goals, see
  7249     below);
  7250   - append all possible rule selections, but only use the first
  7251     success (no backtracking);
  7252   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  7253   - undeclared rule case names default to numbers 1, 2, 3, ...;
  7254   - added 'print_induct_rules' (covered by help item in recent Proof
  7255     General versions);
  7256   - moved induct/cases attributes to Pure, methods to Provers;
  7257   - generic method setup instantiated for FOL and HOL;
  7258 
  7259 * Pure: support multiple simultaneous goal statements, for example
  7260 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  7261 meta-level mechanism, this acts as if several individual goals had
  7262 been stated separately; in particular common proof methods need to be
  7263 repeated in order to cover all claims; note that a single elimination
  7264 step is *not* sufficient to establish the two conjunctions, so this
  7265 fails:
  7266 
  7267   assume "A & B" then have A and B ..   (*".." fails*)
  7268 
  7269 better use "obtain" in situations as above; alternative refer to
  7270 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  7271 
  7272 * Pure: proper integration with ``locales''; unlike the original
  7273 version by Florian Kammller, Isar locales package high-level proof
  7274 contexts rather than raw logical ones (e.g. we admit to include
  7275 attributes everywhere); operations on locales include merge and
  7276 rename; support for implicit arguments (``structures''); simultaneous
  7277 type-inference over imports and text; see also HOL/ex/Locales.thy for
  7278 some examples;
  7279 
  7280 * Pure: the following commands have been ``localized'', supporting a
  7281 target locale specification "(in name)": 'lemma', 'theorem',
  7282 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  7283 stored both within the locale and at the theory level (exported and
  7284 qualified by the locale name);
  7285 
  7286 * Pure: theory goals may now be specified in ``long'' form, with
  7287 ad-hoc contexts consisting of arbitrary locale elements. for example
  7288 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  7289 definitions may be given, too); the result is a meta-level rule with
  7290 the context elements being discharged in the obvious way;
  7291 
  7292 * Pure: new proof command 'using' allows to augment currently used
  7293 facts after a goal statement ('using' is syntactically analogous to
  7294 'apply', but acts on the goal's facts only); this allows chained facts
  7295 to be separated into parts given before and after a claim, as in
  7296 ``from a and b have C using d and e <proof>'';
  7297 
  7298 * Pure: renamed "antecedent" case to "rule_context";
  7299 
  7300 * Pure: new 'judgment' command records explicit information about the
  7301 object-logic embedding (used by several tools internally); no longer
  7302 use hard-wired "Trueprop";
  7303 
  7304 * Pure: added 'corollary' command;
  7305 
  7306 * Pure: fixed 'token_translation' command;
  7307 
  7308 * Pure: removed obsolete 'exported' attribute;
  7309 
  7310 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  7311 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  7312 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  7313 
  7314 * Pure: method 'atomize' presents local goal premises as object-level
  7315 statements (atomic meta-level propositions); setup controlled via
  7316 rewrite rules declarations of 'atomize' attribute; example
  7317 application: 'induct' method with proper rule statements in improper
  7318 proof *scripts*;
  7319 
  7320 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  7321 now consider the syntactic context of assumptions, giving a better
  7322 chance to get type-inference of the arguments right (this is
  7323 especially important for locales);
  7324 
  7325 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  7326 mode;
  7327 
  7328 * Pure/obtain: the formal conclusion "thesis", being marked as
  7329 ``internal'', may no longer be reference directly in the text;
  7330 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  7331 situations;
  7332 
  7333 * Pure: generic 'sym' attribute which declares a rule both as pure
  7334 'elim?' and for the 'symmetric' operation;
  7335 
  7336 * Pure: marginal comments ``--'' may now occur just anywhere in the
  7337 text; the fixed correlation with particular command syntax has been
  7338 discontinued;
  7339 
  7340 * Pure: new method 'rules' is particularly well-suited for proof
  7341 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  7342 but often produces more compact proof terms with less detours;
  7343 
  7344 * Pure/Provers/classical: simplified integration with pure rule
  7345 attributes and methods; the classical "intro?/elim?/dest?"
  7346 declarations coincide with the pure ones; the "rule" method no longer
  7347 includes classically swapped intros; "intro" and "elim" methods no
  7348 longer pick rules from the context; also got rid of ML declarations
  7349 AddXIs/AddXEs/AddXDs; all of this has some potential for
  7350 INCOMPATIBILITY;
  7351 
  7352 * Provers/classical: attribute 'swapped' produces classical inversions
  7353 of introduction rules;
  7354 
  7355 * Provers/simplifier: 'simplified' attribute may refer to explicit
  7356 rules instead of full simplifier context; 'iff' attribute handles
  7357 conditional rules;
  7358 
  7359 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  7360 
  7361 * HOL: 'recdef' now fails on unfinished automated proofs, use
  7362 "(permissive)" option to recover old behavior;
  7363 
  7364 * HOL: 'inductive' no longer features separate (collective) attributes
  7365 for 'intros' (was found too confusing);
  7366 
  7367 * HOL: properly declared induction rules less_induct and
  7368 wf_induct_rule;
  7369 
  7370 
  7371 *** HOL ***
  7372 
  7373 * HOL: moved over to sane numeral syntax; the new policy is as
  7374 follows:
  7375 
  7376   - 0 and 1 are polymorphic constants, which are defined on any
  7377   numeric type (nat, int, real etc.);
  7378 
  7379   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  7380   binary representation internally;
  7381 
  7382   - type nat has special constructor Suc, and generally prefers Suc 0
  7383   over 1::nat and Suc (Suc 0) over 2::nat;
  7384 
  7385 This change may cause significant problems of INCOMPATIBILITY; here
  7386 are some hints on converting existing sources:
  7387 
  7388   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  7389   entities, so expressions involving "-" (unary or binary minus) need
  7390   to be spaced properly;
  7391 
  7392   - existing occurrences of "1" may need to be constraint "1::nat" or
  7393   even replaced by Suc 0; similar for old "2";
  7394 
  7395   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  7396 
  7397   - remove all special provisions on numerals in proofs;
  7398 
  7399 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  7400 representation (depends on bin_arith_simps in the default context);
  7401 
  7402 * HOL: symbolic syntax for x^2 (numeral 2);
  7403 
  7404 * HOL: the class of all HOL types is now called "type" rather than
  7405 "term"; INCOMPATIBILITY, need to adapt references to this type class
  7406 in axclass/classes, instance/arities, and (usually rare) occurrences
  7407 in typings (of consts etc.); internally the class is called
  7408 "HOL.type", ML programs should refer to HOLogic.typeS;
  7409 
  7410 * HOL/record package improvements:
  7411   - new derived operations "fields" to build a partial record section,
  7412     "extend" to promote a fixed record to a record scheme, and
  7413     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  7414     declared as simp by default;
  7415   - shared operations ("more", "fields", etc.) now need to be always
  7416     qualified) --- potential INCOMPATIBILITY;
  7417   - removed "make_scheme" operations (use "make" with "extend") --
  7418     INCOMPATIBILITY;
  7419   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  7420   - provides cases/induct rules for use with corresponding Isar
  7421     methods (for concrete records, record schemes, concrete more
  7422     parts, and schematic more parts -- in that order);
  7423   - internal definitions directly based on a light-weight abstract
  7424     theory of product types over typedef rather than datatype;
  7425 
  7426 * HOL: generic code generator for generating executable ML code from
  7427 specifications; specific support for HOL constructs such as inductive
  7428 datatypes and sets, as well as recursive functions; can be invoked
  7429 via 'generate_code' theory section;
  7430 
  7431 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  7432 
  7433 * HOL: consolidated and renamed several theories.  In particular:
  7434         Ord.thy has been absorbed into HOL.thy
  7435         String.thy has been absorbed into List.thy
  7436 
  7437 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  7438 (beware of argument permutation!);
  7439 
  7440 * HOL: linorder_less_split superseded by linorder_cases;
  7441 
  7442 * HOL/List: "nodups" renamed to "distinct";
  7443 
  7444 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  7445 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  7446   - Ex_def has changed, now need to use some_eq_ex
  7447 
  7448 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  7449 in this (rare) case use:
  7450 
  7451   delSWrapper "split_all_tac"
  7452   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  7453 
  7454 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  7455 MAY FAIL;
  7456 
  7457 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  7458 Isabelle's type classes, ^ on functions and relations has too general
  7459 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  7460 necessary to attach explicit type constraints;
  7461 
  7462 * HOL/Relation: the prefix name of the infix "O" has been changed from
  7463 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  7464 renamed accordingly (eg "compI" -> "rel_compI").
  7465 
  7466 * HOL: syntax translations now work properly with numerals and records
  7467 expressions;
  7468 
  7469 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  7470 of "lam" -- INCOMPATIBILITY;
  7471 
  7472 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  7473 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  7474 renamed "Product_Type.unit";
  7475 
  7476 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  7477 
  7478 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  7479 the "cases" method);
  7480 
  7481 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  7482 Florian Kammller);
  7483 
  7484 * HOL/IMP: updated and converted to new-style theory format; several
  7485 parts turned into readable document, with proper Isar proof texts and
  7486 some explanations (by Gerwin Klein);
  7487 
  7488 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  7489 
  7490 * HOL-Hyperreal is now a logic image;
  7491 
  7492 
  7493 *** HOLCF ***
  7494 
  7495 * Isar: consts/constdefs supports mixfix syntax for continuous
  7496 operations;
  7497 
  7498 * Isar: domain package adapted to new-style theory format, e.g. see
  7499 HOLCF/ex/Dnat.thy;
  7500 
  7501 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7502 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7503 lift.induct_tac, always use UU instead of Undef;
  7504 
  7505 * HOLCF/IMP: updated and converted to new-style theory;
  7506 
  7507 
  7508 *** ZF ***
  7509 
  7510 * Isar: proper integration of logic-specific tools and packages,
  7511 including theory commands '(co)inductive', '(co)datatype',
  7512 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7513 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7514 
  7515 * theory Main no longer includes AC; for the Axiom of Choice, base
  7516 your theory on Main_ZFC;
  7517 
  7518 * the integer library now covers quotients and remainders, with many
  7519 laws relating division to addition, multiplication, etc.;
  7520 
  7521 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7522 typeless version of the formalism;
  7523 
  7524 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7525 format;
  7526 
  7527 * ZF/Induct: new directory for examples of inductive definitions,
  7528 including theory Multiset for multiset orderings; converted to
  7529 new-style theory format;
  7530 
  7531 * ZF: many new theorems about lists, ordinals, etc.;
  7532 
  7533 
  7534 *** General ***
  7535 
  7536 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7537 variable proof controls level of detail: 0 = no proofs (only oracle
  7538 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7539 also ref manual for further ML interfaces;
  7540 
  7541 * Pure/axclass: removed obsolete ML interface
  7542 goal_subclass/goal_arity;
  7543 
  7544 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7545 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7546 separate tokens, so expressions involving minus need to be spaced
  7547 properly;
  7548 
  7549 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7550 rather than "infixl" or "infixr";
  7551 
  7552 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7553 sort constraint specifications in type inference; e.g. "x::_::foo"
  7554 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7555 type variable);
  7556 
  7557 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7558 control output of nested => (types); the default behavior is
  7559 "type_brackets";
  7560 
  7561 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7562 tokens into AST constants;
  7563 
  7564 * Pure/syntax: prefer later declarations of translations and print
  7565 translation functions; potential INCOMPATIBILITY: need to reverse
  7566 multiple declarations for same syntax element constant;
  7567 
  7568 * Pure/show_hyps reset by default (in accordance to existing Isar
  7569 practice);
  7570 
  7571 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7572 addSafter;
  7573 
  7574 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7575 as well;
  7576 
  7577 * system: tested support for MacOS X; should be able to get Isabelle +
  7578 Proof General to work in a plain Terminal after installing Poly/ML
  7579 (e.g. from the Isabelle distribution area) and GNU bash alone
  7580 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7581 support requires further installations, e.g. from
  7582 http://fink.sourceforge.net/);
  7583 
  7584 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7585 
  7586 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7587 of 40 MB), cf. ML_OPTIONS;
  7588 
  7589 * system: Proof General keywords specification is now part of the
  7590 Isabelle distribution (see etc/isar-keywords.el);
  7591 
  7592 * system: support for persistent Proof General sessions (refrain from
  7593 outdating all loaded theories on startup); user may create writable
  7594 logic images like this: ``isabelle -q HOL Test'';
  7595 
  7596 * system: smart selection of Isabelle process versus Isabelle
  7597 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7598 run both "isabelle" and "Isabelle" even if file names are badly
  7599 damaged (executable inspects the case of the first letter of its own
  7600 name); added separate "isabelle-process" and "isabelle-interface";
  7601 
  7602 * system: refrain from any attempt at filtering input streams; no
  7603 longer support ``8bit'' encoding of old isabelle font, instead proper
  7604 iso-latin characters may now be used; the related isatools
  7605 "symbolinput" and "nonascii" have disappeared as well;
  7606 
  7607 * system: removed old "xterm" interface (the print modes "xterm" and
  7608 "xterm_color" are still available for direct use in a suitable
  7609 terminal);
  7610 
  7611 
  7612 
  7613 New in Isabelle99-2 (February 2001)
  7614 -----------------------------------
  7615 
  7616 *** Overview of INCOMPATIBILITIES ***
  7617 
  7618 * HOL: please note that theories in the Library and elsewhere often use the
  7619 new-style (Isar) format; to refer to their theorems in an ML script you must
  7620 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  7621 
  7622 * HOL: inductive package no longer splits induction rule aggressively,
  7623 but only as far as specified by the introductions given; the old
  7624 format may be recovered via ML function complete_split_rule or attribute
  7625 'split_rule (complete)';
  7626 
  7627 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  7628 gfp_Tarski to gfp_unfold;
  7629 
  7630 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  7631 
  7632 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  7633 relation); infix "^^" has been renamed "``"; infix "``" has been
  7634 renamed "`"; "univalent" has been renamed "single_valued";
  7635 
  7636 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  7637 operation;
  7638 
  7639 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  7640 
  7641 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  7642 
  7643 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  7644 consequence, it is no longer monotonic wrt. the local goal context
  7645 (which is now passed through the inductive cases);
  7646 
  7647 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  7648 \<gg> to \<ggreater>;
  7649 
  7650 
  7651 *** Document preparation ***
  7652 
  7653 * \isabellestyle{NAME} selects version of Isabelle output (currently
  7654 available: are "it" for near math-mode best-style output, "sl" for
  7655 slanted text style, and "tt" for plain type-writer; if no
  7656 \isabellestyle command is given, output is according to slanted
  7657 type-writer);
  7658 
  7659 * support sub/super scripts (for single symbols only), input syntax is
  7660 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  7661 
  7662 * some more standard symbols; see Appendix A of the system manual for
  7663 the complete list of symbols defined in isabellesym.sty;
  7664 
  7665 * improved isabelle style files; more abstract symbol implementation
  7666 (should now use \isamath{...} and \isatext{...} in custom symbol
  7667 definitions);
  7668 
  7669 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  7670 state; Note that presentation of goal states does not conform to
  7671 actual human-readable proof documents.  Please do not include goal
  7672 states into document output unless you really know what you are doing!
  7673 
  7674 * proper indentation of antiquoted output with proportional LaTeX
  7675 fonts;
  7676 
  7677 * no_document ML operator temporarily disables LaTeX document
  7678 generation;
  7679 
  7680 * isatool unsymbolize tunes sources for plain ASCII communication;
  7681 
  7682 
  7683 *** Isar ***
  7684 
  7685 * Pure: Isar now suffers initial goal statements to contain unbound
  7686 schematic variables (this does not conform to actual readable proof
  7687 documents, due to unpredictable outcome and non-compositional proof
  7688 checking); users who know what they are doing may use schematic goals
  7689 for Prolog-style synthesis of proven results;
  7690 
  7691 * Pure: assumption method (an implicit finishing) now handles actual
  7692 rules as well;
  7693 
  7694 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  7695 initial goal, declare "that" only as Pure intro (only for single
  7696 steps); the "that" rule assumption may now be involved in implicit
  7697 finishing, thus ".." becomes a feasible for trivial obtains;
  7698 
  7699 * Pure: default proof step now includes 'intro_classes'; thus trivial
  7700 instance proofs may be performed by "..";
  7701 
  7702 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  7703 statements as well;
  7704 
  7705 * Pure: more robust selection of calculational rules;
  7706 
  7707 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  7708 rule (as well as the assumption rule);
  7709 
  7710 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  7711 lemmas, using the graph browser tool;
  7712 
  7713 * Pure: predict failure of "show" in interactive mode;
  7714 
  7715 * Pure: 'thms_containing' now takes actual terms as arguments;
  7716 
  7717 * HOL: improved method 'induct' --- now handles non-atomic goals
  7718 (potential INCOMPATIBILITY); tuned error handling;
  7719 
  7720 * HOL: cases and induct rules now provide explicit hints about the
  7721 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  7722 any remaining facts are inserted into the goal verbatim;
  7723 
  7724 * HOL: local contexts (aka cases) may now contain term bindings as
  7725 well; the 'cases' and 'induct' methods new provide a ?case binding for
  7726 the result to be shown in each case;
  7727 
  7728 * HOL: added 'recdef_tc' command;
  7729 
  7730 * isatool convert assists in eliminating legacy ML scripts;
  7731 
  7732 
  7733 *** HOL ***
  7734 
  7735 * HOL/Library: a collection of generic theories to be used together
  7736 with main HOL; the theory loader path already includes this directory
  7737 by default; the following existing theories have been moved here:
  7738 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  7739 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  7740 
  7741 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  7742 modelling and verification task performed in Isabelle/HOL +
  7743 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  7744 
  7745 * HOL/Algebra: special summation operator SUM no longer exists, it has
  7746 been replaced by setsum; infix 'assoc' now has priority 50 (like
  7747 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  7748 'domain', this makes the theory consistent with mathematical
  7749 literature;
  7750 
  7751 * HOL basics: added overloaded operations "inverse" and "divide"
  7752 (infix "/"), syntax for generic "abs" operation, generic summation
  7753 operator \<Sum>;
  7754 
  7755 * HOL/typedef: simplified package, provide more useful rules (see also
  7756 HOL/subset.thy);
  7757 
  7758 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  7759 now expressed as a proper nested rule (old-style tactic scripts may
  7760 require atomize_strip_tac to cope with non-atomic premises);
  7761 
  7762 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  7763 to "split_conv" (old name still available for compatibility);
  7764 
  7765 * HOL: improved concrete syntax for strings (e.g. allows translation
  7766 rules with string literals);
  7767 
  7768 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  7769  and Fleuriot's mechanization of analysis, including the transcendental
  7770  functions for the reals;
  7771 
  7772 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  7773 
  7774 
  7775 *** CTT ***
  7776 
  7777 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  7778 "lam" is displayed as TWO lambda-symbols
  7779 
  7780 * CTT: theory Main now available, containing everything (that is, Bool
  7781 and Arith);
  7782 
  7783 
  7784 *** General ***
  7785 
  7786 * Pure: the Simplifier has been implemented properly as a derived rule
  7787 outside of the actual kernel (at last!); the overall performance
  7788 penalty in practical applications is about 50%, while reliability of
  7789 the Isabelle inference kernel has been greatly improved;
  7790 
  7791 * print modes "brackets" and "no_brackets" control output of nested =>
  7792 (types) and ==> (props); the default behaviour is "brackets";
  7793 
  7794 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7795 as assumptions as well;
  7796 
  7797 * system: support Poly/ML 4.0;
  7798 
  7799 * system: isatool install handles KDE version 1 or 2;
  7800 
  7801 
  7802 
  7803 New in Isabelle99-1 (October 2000)
  7804 ----------------------------------
  7805 
  7806 *** Overview of INCOMPATIBILITIES ***
  7807 
  7808 * HOL: simplification of natural numbers is much changed; to partly
  7809 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7810 issue the following ML commands:
  7811 
  7812   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7813   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7814 
  7815 * HOL: simplification no longer dives into case-expressions; this is
  7816 controlled by "t.weak_case_cong" for each datatype t;
  7817 
  7818 * HOL: nat_less_induct renamed to less_induct;
  7819 
  7820 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7821 fixsome to patch .thy and .ML sources automatically;
  7822 
  7823   select_equality  -> some_equality
  7824   select_eq_Ex     -> some_eq_ex
  7825   selectI2EX       -> someI2_ex
  7826   selectI2         -> someI2
  7827   selectI          -> someI
  7828   select1_equality -> some1_equality
  7829   Eps_sym_eq       -> some_sym_eq_trivial
  7830   Eps_eq           -> some_eq_trivial
  7831 
  7832 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7833 
  7834 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7835 instead);
  7836 
  7837 * HOL: the recursion equations generated by 'recdef' are now called
  7838 f.simps instead of f.rules;
  7839 
  7840 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7841 
  7842 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7843 sometimes be needed;
  7844 
  7845 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7846 
  7847 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7848 
  7849 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7850 product is now "<*>" instead of "Times"; the lexicographic product is
  7851 now "<*lex*>" instead of "**";
  7852 
  7853 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7854 of main HOL, but was unused); better use HOL's datatype package;
  7855 
  7856 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7857 the old syntax may be recovered as follows:
  7858 
  7859   syntax (symbols)
  7860     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7861       (infixl "\\<oplus>" 100)
  7862 
  7863 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7864 
  7865 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7866 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7867 internally;
  7868 
  7869 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7870 changed from A/r to A//r;
  7871 
  7872 * ZF: new treatment of arithmetic (nat & int) may break some old
  7873 proofs;
  7874 
  7875 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7876 rulify -> rule_format, elimify -> elim_format, ...);
  7877 
  7878 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7879 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7880 should have to change intro!! to intro? only); replaced "delrule" by
  7881 "rule del";
  7882 
  7883 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7884 
  7885 * Provers: strengthened force_tac by using new first_best_tac;
  7886 
  7887 * LaTeX document preparation: several changes of isabelle.sty (see
  7888 lib/texinputs);
  7889 
  7890 
  7891 *** Document preparation ***
  7892 
  7893 * formal comments (text blocks etc.) in new-style theories may now
  7894 contain antiquotations of thm/prop/term/typ/text to be presented
  7895 according to latex print mode; concrete syntax is like this:
  7896 @{term[show_types] "f(x) = a + x"};
  7897 
  7898 * isatool mkdir provides easy setup of Isabelle session directories,
  7899 including proper document sources;
  7900 
  7901 * generated LaTeX sources are now deleted after successful run
  7902 (isatool document -c); may retain a copy somewhere else via -D option
  7903 of isatool usedir;
  7904 
  7905 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7906 style files, achieving self-contained LaTeX sources and simplifying
  7907 LaTeX debugging;
  7908 
  7909 * old-style theories now produce (crude) LaTeX output as well;
  7910 
  7911 * browser info session directories are now self-contained (may be put
  7912 on WWW server seperately); improved graphs of nested sessions; removed
  7913 graph for 'all sessions';
  7914 
  7915 * several improvements in isabelle style files; \isabellestyle{it}
  7916 produces fake math mode output; \isamarkupheader is now \section by
  7917 default; see lib/texinputs/isabelle.sty etc.;
  7918 
  7919 
  7920 *** Isar ***
  7921 
  7922 * Isar/Pure: local results and corresponding term bindings are now
  7923 subject to Hindley-Milner polymorphism (similar to ML); this
  7924 accommodates incremental type-inference very nicely;
  7925 
  7926 * Isar/Pure: new derived language element 'obtain' supports
  7927 generalized existence reasoning;
  7928 
  7929 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7930 support accumulation of results, without applying any rules yet;
  7931 useful to collect intermediate results without explicit name
  7932 references, and for use with transitivity rules with more than 2
  7933 premises;
  7934 
  7935 * Isar/Pure: scalable support for case-analysis type proofs: new
  7936 'case' language element refers to local contexts symbolically, as
  7937 produced by certain proof methods; internally, case names are attached
  7938 to theorems as "tags";
  7939 
  7940 * Isar/Pure: theory command 'hide' removes declarations from
  7941 class/type/const name spaces;
  7942 
  7943 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7944 indicate potential overloading;
  7945 
  7946 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7947 
  7948 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7949 "{a,b,c}" instead of {a,b,c};
  7950 
  7951 * Isar/Pure now provides its own version of intro/elim/dest
  7952 attributes; useful for building new logics, but beware of confusion
  7953 with the version in Provers/classical;
  7954 
  7955 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7956 case name 'antecedent';
  7957 
  7958 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7959 to the current context is now done automatically);
  7960 
  7961 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7962 for definining proof methods in ML;
  7963 
  7964 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7965 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7966 most cases, one should have to change intro!! to intro? only);
  7967 replaced "delrule" by "rule del";
  7968 
  7969 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7970 'symmetric' attribute (the latter supercedes [RS sym]);
  7971 
  7972 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7973 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7974 well (including splits);
  7975 
  7976 * Isar/Provers: Simplifier and Classical methods now support all kind
  7977 of modifiers used in the past, including 'cong', 'iff', etc.
  7978 
  7979 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7980 of Simplifier and Classical reasoner);
  7981 
  7982 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7983 now support named cases; major packages (inductive, datatype, primrec,
  7984 recdef) support case names and properly name parameters;
  7985 
  7986 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7987 monotonicity conditions are extracted to be proven at end of
  7988 calculations;
  7989 
  7990 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7991 method anyway;
  7992 
  7993 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7994 split_if split_if_asm; datatype package provides theorems foo.splits =
  7995 foo.split foo.split_asm for each datatype;
  7996 
  7997 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7998 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7999 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  8000 use "(cases (simplified))" method in proper proof texts);
  8001 
  8002 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  8003 
  8004 * Isar: names of theorems etc. may be natural numbers as well;
  8005 
  8006 * Isar: 'pr' command: optional arguments for goals_limit and
  8007 ProofContext.prems_limit; no longer prints theory contexts, but only
  8008 proof states;
  8009 
  8010 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  8011 additional print modes to be specified; e.g. "pr(latex)" will print
  8012 proof state according to the Isabelle LaTeX style;
  8013 
  8014 * Isar: improved support for emulating tactic scripts, including proof
  8015 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  8016 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  8017 (for HOL datatypes);
  8018 
  8019 * Isar: simplified (more robust) goal selection of proof methods: 1st
  8020 goal, all goals, or explicit goal specifier (tactic emulation); thus
  8021 'proof method scripts' have to be in depth-first order;
  8022 
  8023 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  8024 
  8025 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  8026 should instead use individual commands for printing items
  8027 (print_commands, print_methods etc.);
  8028 
  8029 * Isar: added 'nothing' --- the empty list of theorems;
  8030 
  8031 
  8032 *** HOL ***
  8033 
  8034 * HOL/MicroJava: formalization of a fragment of Java, together with a
  8035 corresponding virtual machine and a specification of its bytecode
  8036 verifier and a lightweight bytecode verifier, including proofs of
  8037 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  8038 Cornelia Pusch (see also the homepage of project Bali at
  8039 http://isabelle.in.tum.de/Bali/);
  8040 
  8041 * HOL/Algebra: new theory of rings and univariate polynomials, by
  8042 Clemens Ballarin;
  8043 
  8044 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  8045 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  8046 Rasmussen;
  8047 
  8048 * HOL/Lattice: fundamental concepts of lattice theory and order
  8049 structures, including duals, properties of bounds versus algebraic
  8050 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  8051 Theorem for complete lattices etc.; may also serve as a demonstration
  8052 for abstract algebraic reasoning using axiomatic type classes, and
  8053 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  8054 
  8055 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  8056 von Oheimb;
  8057 
  8058 * HOL/IMPP: extension of IMP with local variables and mutually
  8059 recursive procedures, by David von Oheimb;
  8060 
  8061 * HOL/Lambda: converted into new-style theory and document;
  8062 
  8063 * HOL/ex/Multiquote: example of multiple nested quotations and
  8064 anti-quotations -- basically a generalized version of de-Bruijn
  8065 representation; very useful in avoiding lifting of operations;
  8066 
  8067 * HOL/record: added general record equality rule to simpset; fixed
  8068 select-update simplification procedure to handle extended records as
  8069 well; admit "r" as field name;
  8070 
  8071 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  8072 other numeric types and also as the identity of groups, rings, etc.;
  8073 
  8074 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  8075 Types nat and int belong to this axclass;
  8076 
  8077 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  8078    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  8079    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  8080   two terms #m*u and #n*u are replaced by #(m+n)*u
  8081     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  8082   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  8083     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  8084 
  8085 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  8086 powerful prover for predicate logic but knows nothing of clasets; see
  8087 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  8088 
  8089 * HOL: new version of "case_tac" subsumes both boolean case split and
  8090 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  8091 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  8092 
  8093 * HOL: simplification no longer dives into case-expressions: only the
  8094 selector expression is simplified, but not the remaining arms; to
  8095 enable full simplification of case-expressions for datatype t, you may
  8096 remove t.weak_case_cong from the simpset, either globally (Delcongs
  8097 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  8098 
  8099 * HOL/recdef: the recursion equations generated by 'recdef' for
  8100 function 'f' are now called f.simps instead of f.rules; if all
  8101 termination conditions are proved automatically, these simplification
  8102 rules are added to the simpset, as in primrec; rules may be named
  8103 individually as well, resulting in a separate list of theorems for
  8104 each equation;
  8105 
  8106 * HOL/While is a new theory that provides a while-combinator. It
  8107 permits the definition of tail-recursive functions without the
  8108 provision of a termination measure. The latter is necessary once the
  8109 invariant proof rule for while is applied.
  8110 
  8111 * HOL: new (overloaded) notation for the set of elements below/above
  8112 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  8113 
  8114 * HOL: theorems impI, allI, ballI bound as "strip";
  8115 
  8116 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  8117 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  8118 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  8119 
  8120 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  8121 
  8122 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  8123 main HOL, but was unused);
  8124 
  8125 * HOL: fewer consts declared as global (e.g. have to refer to
  8126 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  8127 
  8128 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  8129 in case of overlap with user translations (e.g. judgements over
  8130 tuples); (note that the underlying logical represenation is still
  8131 bogus);
  8132 
  8133 
  8134 *** ZF ***
  8135 
  8136 * ZF: simplification automatically cancels common terms in arithmetic
  8137 expressions over nat and int;
  8138 
  8139 * ZF: new treatment of nat to minimize type-checking: all operators
  8140 coerce their operands to a natural number using the function natify,
  8141 making the algebraic laws unconditional;
  8142 
  8143 * ZF: as above, for int: operators coerce their operands to an integer
  8144 using the function intify;
  8145 
  8146 * ZF: the integer library now contains many of the usual laws for the
  8147 orderings, including $<=, and monotonicity laws for $+ and $*;
  8148 
  8149 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  8150 simplification;
  8151 
  8152 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  8153 to the simplifier and classical reasoner simultaneously;
  8154 
  8155 
  8156 *** General ***
  8157 
  8158 * Provers: blast_tac now handles actual object-logic rules as
  8159 assumptions; note that auto_tac uses blast_tac internally as well;
  8160 
  8161 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  8162 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  8163 
  8164 * Provers: delrules now handles destruct rules as well (no longer need
  8165 explicit make_elim);
  8166 
  8167 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  8168   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8169 use instead the strong form,
  8170   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8171 in HOL, FOL and ZF the function cla_make_elim will create such rules
  8172 from destruct-rules;
  8173 
  8174 * Provers: Simplifier.easy_setup provides a fast path to basic
  8175 Simplifier setup for new object-logics;
  8176 
  8177 * Pure: AST translation rules no longer require constant head on LHS;
  8178 
  8179 * Pure: improved name spaces: ambiguous output is qualified; support
  8180 for hiding of names;
  8181 
  8182 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  8183 XSYMBOL_HOME; no longer need to do manual configuration in most
  8184 situations;
  8185 
  8186 * system: compression of ML heaps images may now be controlled via -c
  8187 option of isabelle and isatool usedir (currently only observed by
  8188 Poly/ML);
  8189 
  8190 * system: isatool installfonts may handle X-Symbol fonts as well (very
  8191 useful for remote X11);
  8192 
  8193 * system: provide TAGS file for Isabelle sources;
  8194 
  8195 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  8196 order;
  8197 
  8198 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  8199 timing flag supersedes proof_timing and Toplevel.trace;
  8200 
  8201 * ML: new combinators |>> and |>>> for incremental transformations
  8202 with secondary results (e.g. certain theory extensions):
  8203 
  8204 * ML: PureThy.add_defs gets additional argument to indicate potential
  8205 overloading (usually false);
  8206 
  8207 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  8208 results;
  8209 
  8210 
  8211 
  8212 New in Isabelle99 (October 1999)
  8213 --------------------------------
  8214 
  8215 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8216 
  8217 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  8218 are no longer simplified.  (This allows the simplifier to unfold recursive
  8219 functional programs.)  To restore the old behaviour, declare
  8220 
  8221     Delcongs [if_weak_cong];
  8222 
  8223 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  8224 complement;
  8225 
  8226 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  8227 
  8228 * HOL/datatype: mutual_induct_tac no longer exists --
  8229   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  8230 
  8231 * HOL/typedef: fixed type inference for representing set; type
  8232 arguments now have to occur explicitly on the rhs as type constraints;
  8233 
  8234 * ZF: The con_defs part of an inductive definition may no longer refer
  8235 to constants declared in the same theory;
  8236 
  8237 * HOL, ZF: the function mk_cases, generated by the inductive
  8238 definition package, has lost an argument.  To simplify its result, it
  8239 uses the default simpset instead of a supplied list of theorems.
  8240 
  8241 * HOL/List: the constructors of type list are now Nil and Cons;
  8242 
  8243 * Simplifier: the type of the infix ML functions
  8244         setSSolver addSSolver setSolver addSolver
  8245 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  8246 for packaging solvers. A solver is created via
  8247         mk_solver: string -> (thm list -> int -> tactic) -> solver
  8248 where the string argument is only a comment.
  8249 
  8250 
  8251 *** Proof tools ***
  8252 
  8253 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  8254 decision procedure for linear arithmetic. Currently it is used for
  8255 types `nat', `int', and `real' in HOL (see below); it can, should and
  8256 will be instantiated for other types and logics as well.
  8257 
  8258 * The simplifier now accepts rewrite rules with flexible heads, eg
  8259      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  8260   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  8261   matching.
  8262 
  8263 
  8264 *** General ***
  8265 
  8266 * New Isabelle/Isar subsystem provides an alternative to traditional
  8267 tactical theorem proving; together with the ProofGeneral/isar user
  8268 interface it offers an interactive environment for developing human
  8269 readable proof documents (Isar == Intelligible semi-automated
  8270 reasoning); for further information see isatool doc isar-ref,
  8271 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  8272 
  8273 * improved and simplified presentation of theories: better HTML markup
  8274 (including colors), graph views in several sizes; isatool usedir now
  8275 provides a proper interface for user theories (via -P option); actual
  8276 document preparation based on (PDF)LaTeX is available as well (for
  8277 new-style theories only); see isatool doc system for more information;
  8278 
  8279 * native support for Proof General, both for classic Isabelle and
  8280 Isabelle/Isar;
  8281 
  8282 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  8283 using the graph browser tool;
  8284 
  8285 * Isabelle manuals now also available as PDF;
  8286 
  8287 * theory loader rewritten from scratch (may not be fully
  8288 bug-compatible); old loadpath variable has been replaced by show_path,
  8289 add_path, del_path, reset_path functions; new operations such as
  8290 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  8291 isatool doc ref);
  8292 
  8293 * improved isatool install: option -k creates KDE application icon,
  8294 option -p DIR installs standalone binaries;
  8295 
  8296 * added ML_PLATFORM setting (useful for cross-platform installations);
  8297 more robust handling of platform specific ML images for SML/NJ;
  8298 
  8299 * the settings environment is now statically scoped, i.e. it is never
  8300 created again in sub-processes invoked from isabelle, isatool, or
  8301 Isabelle;
  8302 
  8303 * path element specification '~~' refers to '$ISABELLE_HOME';
  8304 
  8305 * in locales, the "assumes" and "defines" parts may be omitted if
  8306 empty;
  8307 
  8308 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  8309 long arrows);
  8310 
  8311 * new print_mode "HTML";
  8312 
  8313 * new flag show_tags controls display of tags of theorems (which are
  8314 basically just comments that may be attached by some tools);
  8315 
  8316 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  8317 mode and goal output format:
  8318 
  8319 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  8320 244c244
  8321 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  8322 ---
  8323 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  8324 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  8325 181c181
  8326 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  8327 ---
  8328 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  8329 
  8330 * function bind_thms stores lists of theorems (cf. bind_thm);
  8331 
  8332 * new shorthand tactics ftac, eatac, datac, fatac;
  8333 
  8334 * qed (and friends) now accept "" as result name; in that case the
  8335 theorem is not stored, but proper checks and presentation of the
  8336 result still apply;
  8337 
  8338 * theorem database now also indexes constants "Trueprop", "all",
  8339 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  8340 
  8341 
  8342 *** HOL ***
  8343 
  8344 ** HOL arithmetic **
  8345 
  8346 * There are now decision procedures for linear arithmetic over nat and
  8347 int:
  8348 
  8349 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  8350 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  8351 are treated as atomic; subformulae not involving type `nat' or `int'
  8352 are ignored; quantified subformulae are ignored unless they are
  8353 positive universal or negative existential. The tactic has to be
  8354 invoked by hand and can be a little bit slow. In particular, the
  8355 running time is exponential in the number of occurrences of `min' and
  8356 `max', and `-' on `nat'.
  8357 
  8358 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  8359 (negated) (in)equalities among the premises and the conclusion into
  8360 account (i.e. no compound formulae) and does not know about `min' and
  8361 `max', and `-' on `nat'. It is fast and is used automatically by the
  8362 simplifier.
  8363 
  8364 NB: At the moment, these decision procedures do not cope with mixed
  8365 nat/int formulae where the two parts interact, such as `m < n ==>
  8366 int(m) < int(n)'.
  8367 
  8368 * HOL/Numeral provides a generic theory of numerals (encoded
  8369 efficiently as bit strings); setup for types nat/int/real is in place;
  8370 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  8371 int, existing theories and proof scripts may require a few additional
  8372 type constraints;
  8373 
  8374 * integer division and remainder can now be performed on constant
  8375 arguments;
  8376 
  8377 * many properties of integer multiplication, division and remainder
  8378 are now available;
  8379 
  8380 * An interface to the Stanford Validity Checker (SVC) is available through the
  8381 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  8382 are proved automatically.  SVC must be installed separately, and its results
  8383 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  8384 invocation of the underlying oracle).  For SVC see
  8385   http://verify.stanford.edu/SVC
  8386 
  8387 * IsaMakefile: the HOL-Real target now builds an actual image;
  8388 
  8389 
  8390 ** HOL misc **
  8391 
  8392 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  8393 (in Isabelle/Isar) -- by Gertrud Bauer;
  8394 
  8395 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  8396 analysis for assembly languages with subtypes;
  8397 
  8398 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  8399 -- avoids syntactic ambiguities and treats state, transition, and
  8400 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  8401 changed syntax and (many) tactics;
  8402 
  8403 * HOL/inductive: Now also handles more general introduction rules such
  8404   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  8405   theorems are now maintained within the theory (maintained via the
  8406   "mono" attribute);
  8407 
  8408 * HOL/datatype: Now also handles arbitrarily branching datatypes
  8409   (using function types) such as
  8410 
  8411   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  8412 
  8413 * HOL/record: record_simproc (part of the default simpset) takes care
  8414 of selectors applied to updated records; record_split_tac is no longer
  8415 part of the default claset; update_defs may now be removed from the
  8416 simpset in many cases; COMPATIBILITY: old behavior achieved by
  8417 
  8418   claset_ref () := claset() addSWrapper record_split_wrapper;
  8419   Delsimprocs [record_simproc]
  8420 
  8421 * HOL/typedef: fixed type inference for representing set; type
  8422 arguments now have to occur explicitly on the rhs as type constraints;
  8423 
  8424 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  8425 names rather than an ML expression;
  8426 
  8427 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  8428 supplied later.  Program schemes can be defined, such as
  8429     "While B C s = (if B s then While B C (C s) else s)"
  8430 where the well-founded relation can be chosen after B and C have been given.
  8431 
  8432 * HOL/List: the constructors of type list are now Nil and Cons;
  8433 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  8434 course, ML tools referring to List.list.op # etc. have to be adapted;
  8435 
  8436 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  8437 disabled by default; run isabelle with option -m HOL to get back to
  8438 the original Gordon/HOL-style output;
  8439 
  8440 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  8441 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  8442 
  8443 * HOL basic syntax simplified (more orthogonal): all variants of
  8444 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  8445 Eps operator is provided as well: "SOME x. P[x]";
  8446 
  8447 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  8448 
  8449 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  8450 thus available for user theories;
  8451 
  8452 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  8453 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  8454 time;
  8455 
  8456 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  8457 several times and then mp;
  8458 
  8459 
  8460 *** LK ***
  8461 
  8462 * the notation <<...>> is now available as a notation for sequences of
  8463 formulas;
  8464 
  8465 * the simplifier is now installed
  8466 
  8467 * the axiom system has been generalized (thanks to Soren Heilmann)
  8468 
  8469 * the classical reasoner now has a default rule database
  8470 
  8471 
  8472 *** ZF ***
  8473 
  8474 * new primrec section allows primitive recursive functions to be given
  8475 directly (as in HOL) over datatypes and the natural numbers;
  8476 
  8477 * new tactics induct_tac and exhaust_tac for induction (or case
  8478 analysis) over datatypes and the natural numbers;
  8479 
  8480 * the datatype declaration of type T now defines the recursor T_rec;
  8481 
  8482 * simplification automatically does freeness reasoning for datatype
  8483 constructors;
  8484 
  8485 * automatic type-inference, with AddTCs command to insert new
  8486 type-checking rules;
  8487 
  8488 * datatype introduction rules are now added as Safe Introduction rules
  8489 to the claset;
  8490 
  8491 * the syntax "if P then x else y" is now available in addition to
  8492 if(P,x,y);
  8493 
  8494 
  8495 *** Internal programming interfaces ***
  8496 
  8497 * tuned simplifier trace output; new flag debug_simp;
  8498 
  8499 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8500 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8501 
  8502 * AxClass.axclass_tac lost the theory argument;
  8503 
  8504 * tuned current_goals_markers semantics: begin / end goal avoids
  8505 printing empty lines;
  8506 
  8507 * removed prs and prs_fn hook, which was broken because it did not
  8508 include \n in its semantics, forcing writeln to add one
  8509 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8510 string -> unit if you really want to output text without newline;
  8511 
  8512 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8513 plain output, interface builders may have to enable 'isabelle_font'
  8514 mode to get Isabelle font glyphs as before;
  8515 
  8516 * refined token_translation interface; INCOMPATIBILITY: output length
  8517 now of type real instead of int;
  8518 
  8519 * theory loader actions may be traced via new ThyInfo.add_hook
  8520 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8521 your own database of information attached to *whole* theories -- as
  8522 opposed to intra-theory data slots offered via TheoryDataFun;
  8523 
  8524 * proper handling of dangling sort hypotheses (at last!);
  8525 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8526 extra sort hypotheses that can be witnessed from the type signature;
  8527 the force_strip_shyps flag is gone, any remaining shyps are simply
  8528 left in the theorem (with a warning issued by strip_shyps_warning);
  8529 
  8530 
  8531 
  8532 New in Isabelle98-1 (October 1998)
  8533 ----------------------------------
  8534 
  8535 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8536 
  8537 * several changes of automated proof tools;
  8538 
  8539 * HOL: major changes to the inductive and datatype packages, including
  8540 some minor incompatibilities of theory syntax;
  8541 
  8542 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8543 called `inj_on';
  8544 
  8545 * HOL: removed duplicate thms in Arith:
  8546   less_imp_add_less  should be replaced by  trans_less_add1
  8547   le_imp_add_le      should be replaced by  trans_le_add1
  8548 
  8549 * HOL: unary minus is now overloaded (new type constraints may be
  8550 required);
  8551 
  8552 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8553 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8554 now taken as an integer constant.
  8555 
  8556 * Pure: ML function 'theory_of' renamed to 'theory';
  8557 
  8558 
  8559 *** Proof tools ***
  8560 
  8561 * Simplifier:
  8562   1. Asm_full_simp_tac is now more aggressive.
  8563      1. It will sometimes reorient premises if that increases their power to
  8564         simplify.
  8565      2. It does no longer proceed strictly from left to right but may also
  8566         rotate premises to achieve further simplification.
  8567      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8568      old Asm_full_simp_tac in that it does not rotate premises.
  8569   2. The simplifier now knows a little bit about nat-arithmetic.
  8570 
  8571 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8572 allows for selected deletion of wrappers, by introduction of names for
  8573 wrapper functionals.  This implies that addbefore, addSbefore,
  8574 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8575 and that adding two tactics with the same name overwrites the first
  8576 one (emitting a warning).
  8577   type wrapper = (int -> tactic) -> (int -> tactic)
  8578   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8579   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8580   delWrapper, delSWrapper: claset *  string            -> claset
  8581   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8582 
  8583 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8584 semantics; addbefore now affects only the unsafe part of step_tac
  8585 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8586 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8587 by Force_tac;
  8588 
  8589 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8590 compWrapper; added safe wrapper (and access functions for it);
  8591 
  8592 * HOL/split_all_tac is now much faster and fails if there is nothing
  8593 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8594 and the names of the automatically generated variables have changed.
  8595 split_all_tac has moved within claset() from unsafe wrappers to safe
  8596 wrappers, which means that !!-bound variables are split much more
  8597 aggressively, and safe_tac and clarify_tac now split such variables.
  8598 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8599 Note: the same holds for record_split_tac, which does the job of
  8600 split_all_tac for record fields.
  8601 
  8602 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8603 permanently to the default simpset using Addsplits just like
  8604 Addsimps. They can be removed via Delsplits just like
  8605 Delsimps. Lower-case versions are also available.
  8606 
  8607 * HOL/Simplifier: The rule split_if is now part of the default
  8608 simpset. This means that the simplifier will eliminate all occurrences
  8609 of if-then-else in the conclusion of a goal. To prevent this, you can
  8610 either remove split_if completely from the default simpset by
  8611 `Delsplits [split_if]' or remove it in a specific call of the
  8612 simplifier using `... delsplits [split_if]'.  You can also add/delete
  8613 other case splitting rules to/from the default simpset: every datatype
  8614 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  8615 t is the name of the datatype).
  8616 
  8617 * Classical reasoner / Simplifier combination: new force_tac (and
  8618 derivatives Force_tac, force) combines rewriting and classical
  8619 reasoning (and whatever other tools) similarly to auto_tac, but is
  8620 aimed to solve the given subgoal completely.
  8621 
  8622 
  8623 *** General ***
  8624 
  8625 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  8626 and `goalw': the theory is no longer needed as an explicit argument -
  8627 the current theory context is used; assumptions are no longer returned
  8628 at the ML-level unless one of them starts with ==> or !!; it is
  8629 recommended to convert to these new commands using isatool fixgoal
  8630 (backup your sources first!);
  8631 
  8632 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  8633 the current theory context, and 'theory' to lookup stored theories;
  8634 
  8635 * new theory section 'locale' for declaring constants, assumptions and
  8636 definitions that have local scope;
  8637 
  8638 * new theory section 'nonterminals' for purely syntactic types;
  8639 
  8640 * new theory section 'setup' for generic ML setup functions
  8641 (e.g. package initialization);
  8642 
  8643 * the distribution now includes Isabelle icons: see
  8644 lib/logo/isabelle-{small,tiny}.xpm;
  8645 
  8646 * isatool install - install binaries with absolute references to
  8647 ISABELLE_HOME/bin;
  8648 
  8649 * isatool logo -- create instances of the Isabelle logo (as EPS);
  8650 
  8651 * print mode 'emacs' reserved for Isamode;
  8652 
  8653 * support multiple print (ast) translations per constant name;
  8654 
  8655 * theorems involving oracles are now printed with a suffixed [!];
  8656 
  8657 
  8658 *** HOL ***
  8659 
  8660 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  8661 
  8662 * HOL/inductive package reorganized and improved: now supports mutual
  8663 definitions such as
  8664 
  8665   inductive EVEN ODD
  8666     intrs
  8667       null "0 : EVEN"
  8668       oddI "n : EVEN ==> Suc n : ODD"
  8669       evenI "n : ODD ==> Suc n : EVEN"
  8670 
  8671 new theorem list "elims" contains an elimination rule for each of the
  8672 recursive sets; inductive definitions now handle disjunctive premises
  8673 correctly (also ZF);
  8674 
  8675 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  8676 "mutual_induct" no longer exists - the induction rule is always
  8677 contained in "induct";
  8678 
  8679 
  8680 * HOL/datatype package re-implemented and greatly improved: now
  8681 supports mutually recursive datatypes such as
  8682 
  8683   datatype
  8684     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  8685             | SUM ('a aexp) ('a aexp)
  8686             | DIFF ('a aexp) ('a aexp)
  8687             | NUM 'a
  8688   and
  8689     'a bexp = LESS ('a aexp) ('a aexp)
  8690             | AND ('a bexp) ('a bexp)
  8691             | OR ('a bexp) ('a bexp)
  8692 
  8693 as well as indirectly recursive datatypes such as
  8694 
  8695   datatype
  8696     ('a, 'b) term = Var 'a
  8697                   | App 'b ((('a, 'b) term) list)
  8698 
  8699 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  8700 induction on mutually / indirectly recursive datatypes.
  8701 
  8702 Primrec equations are now stored in theory and can be accessed via
  8703 <function_name>.simps.
  8704 
  8705 INCOMPATIBILITIES:
  8706 
  8707   - Theories using datatypes must now have theory Datatype as an
  8708     ancestor.
  8709   - The specific <typename>.induct_tac no longer exists - use the
  8710     generic induct_tac instead.
  8711   - natE has been renamed to nat.exhaust - use exhaust_tac
  8712     instead of res_inst_tac ... natE. Note that the variable
  8713     names in nat.exhaust differ from the names in natE, this
  8714     may cause some "fragile" proofs to fail.
  8715   - The theorems split_<typename>_case and split_<typename>_case_asm
  8716     have been renamed to <typename>.split and <typename>.split_asm.
  8717   - Since default sorts of type variables are now handled correctly,
  8718     some datatype definitions may have to be annotated with explicit
  8719     sort constraints.
  8720   - Primrec definitions no longer require function name and type
  8721     of recursive argument.
  8722 
  8723 Consider using isatool fixdatatype to adapt your theories and proof
  8724 scripts to the new package (backup your sources first!).
  8725 
  8726 
  8727 * HOL/record package: considerably improved implementation; now
  8728 includes concrete syntax for record types, terms, updates; theorems
  8729 for surjective pairing and splitting !!-bound record variables; proof
  8730 support is as follows:
  8731 
  8732   1) standard conversions (selectors or updates applied to record
  8733 constructor terms) are part of the standard simpset;
  8734 
  8735   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  8736 made part of standard simpset and claset via addIffs;
  8737 
  8738   3) a tactic for record field splitting (record_split_tac) is part of
  8739 the standard claset (addSWrapper);
  8740 
  8741 To get a better idea about these rules you may retrieve them via
  8742 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  8743 the name of your record type.
  8744 
  8745 The split tactic 3) conceptually simplifies by the following rule:
  8746 
  8747   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  8748 
  8749 Thus any record variable that is bound by meta-all will automatically
  8750 blow up into some record constructor term, consequently the
  8751 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  8752 solve record problems automatically.
  8753 
  8754 
  8755 * reorganized the main HOL image: HOL/Integ and String loaded by
  8756 default; theory Main includes everything;
  8757 
  8758 * automatic simplification of integer sums and comparisons, using cancellation;
  8759 
  8760 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  8761 
  8762 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  8763 
  8764 * many new identities for unions, intersections, set difference, etc.;
  8765 
  8766 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  8767 called split_if, split_split, split_sum_case and split_nat_case (to go
  8768 with add/delsplits);
  8769 
  8770 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  8771 (?x::unit) = (); this is made part of the default simpset, which COULD
  8772 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  8773 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  8774 unit_abs_eta_conv is added in order to counter the effect of
  8775 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  8776 %u.f();
  8777 
  8778 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  8779 makes more sense);
  8780 
  8781 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8782   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8783   disjointness reasoning but breaking a few old proofs.
  8784 
  8785 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  8786 to 'converse' from 'inverse' (for compatibility with ZF and some
  8787 literature);
  8788 
  8789 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  8790 the well-founded relation;
  8791 
  8792 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8793     Compl A.  The "Compl" syntax remains available as input syntax for this
  8794     release ONLY.
  8795 
  8796 * HOL/Update: new theory of function updates:
  8797     f(a:=b) == %x. if x=a then b else f x
  8798 may also be iterated as in f(a:=b,c:=d,...);
  8799 
  8800 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8801 
  8802 * HOL/List:
  8803   - new function list_update written xs[i:=v] that updates the i-th
  8804     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8805   - new function `upt' written [i..j(] which generates the list
  8806     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8807     bound write [i..j], which is a shorthand for [i..j+1(].
  8808   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8809 
  8810 * HOL/Arith:
  8811   - removed 'pred' (predecessor) function;
  8812   - generalized some theorems about n-1;
  8813   - many new laws about "div" and "mod";
  8814   - new laws about greatest common divisors (see theory ex/Primes);
  8815 
  8816 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8817 instead of "inverse";
  8818 
  8819 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8820   of the multiset ordering;
  8821 
  8822 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8823   (not included by default);
  8824 
  8825 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8826 
  8827 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8828   programs, i.e. different program variables may have different types.
  8829 
  8830 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8831   [previously, this check worked only if the rewrite rule was unconditional]
  8832   Now rew can involve either definitions or equalities (either == or =).
  8833 
  8834 
  8835 *** ZF ***
  8836 
  8837 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8838   only the theorems proved on ZF.ML;
  8839 
  8840 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8841   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8842   disjointness reasoning but breaking a few old proofs.
  8843 
  8844 * ZF/Update: new theory of function updates
  8845     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8846   may also be iterated as in f(a:=b,c:=d,...);
  8847 
  8848 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8849 
  8850 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8851   [previously, this check worked only if the rewrite rule was unconditional]
  8852   Now rew can involve either definitions or equalities (either == or =).
  8853 
  8854 * case_tac provided for compatibility with HOL
  8855     (like the old excluded_middle_tac, but with subgoals swapped)
  8856 
  8857 
  8858 *** Internal programming interfaces ***
  8859 
  8860 * Pure: several new basic modules made available for general use, see
  8861 also src/Pure/README;
  8862 
  8863 * improved the theory data mechanism to support encapsulation (data
  8864 kind name replaced by private Object.kind, acting as authorization
  8865 key); new type-safe user interface via functor TheoryDataFun; generic
  8866 print_data function becomes basically useless;
  8867 
  8868 * removed global_names compatibility flag -- all theory declarations
  8869 are qualified by default;
  8870 
  8871 * module Pure/Syntax now offers quote / antiquote translation
  8872 functions (useful for Hoare logic etc. with implicit dependencies);
  8873 see HOL/ex/Antiquote for an example use;
  8874 
  8875 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8876 cterm -> thm;
  8877 
  8878 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8879 subgoal;
  8880 
  8881 * Display.print_goals function moved to Locale.print_goals;
  8882 
  8883 * standard print function for goals supports current_goals_markers
  8884 variable for marking begin of proof, end of proof, start of goal; the
  8885 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8886 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8887 for example;
  8888 
  8889 
  8890 
  8891 New in Isabelle98 (January 1998)
  8892 --------------------------------
  8893 
  8894 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8895 
  8896 * changed lexical syntax of terms / types: dots made part of long
  8897 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8898 
  8899 * simpset (and claset) reference variable replaced by functions
  8900 simpset / simpset_ref;
  8901 
  8902 * no longer supports theory aliases (via merge) and non-trivial
  8903 implicit merge of thms' signatures;
  8904 
  8905 * most internal names of constants changed due to qualified names;
  8906 
  8907 * changed Pure/Sequence interface (see Pure/seq.ML);
  8908 
  8909 
  8910 *** General Changes ***
  8911 
  8912 * hierachically structured name spaces (for consts, types, axms, thms
  8913 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8914 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8915 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8916 long_names for fully qualified output names; NOTE: ML programs
  8917 (special tactics, packages etc.) referring to internal names may have
  8918 to be adapted to cope with fully qualified names; in case of severe
  8919 backward campatibility problems try setting 'global_names' at compile
  8920 time to have enrything declared within a flat name space; one may also
  8921 fine tune name declarations in theories via the 'global' and 'local'
  8922 section;
  8923 
  8924 * reimplemented the implicit simpset and claset using the new anytype
  8925 data filed in signatures; references simpset:simpset ref etc. are
  8926 replaced by functions simpset:unit->simpset and
  8927 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8928 to patch your ML files accordingly;
  8929 
  8930 * HTML output now includes theory graph data for display with Java
  8931 applet or isatool browser; data generated automatically via isatool
  8932 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8933 
  8934 * defs may now be conditional; improved rewrite_goals_tac to handle
  8935 conditional equations;
  8936 
  8937 * defs now admits additional type arguments, using TYPE('a) syntax;
  8938 
  8939 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8940 creates a new theory node; implicit merge of thms' signatures is
  8941 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8942 transfer:theory->thm->thm in (rare) cases;
  8943 
  8944 * improved handling of draft signatures / theories; draft thms (and
  8945 ctyps, cterms) are automatically promoted to real ones;
  8946 
  8947 * slightly changed interfaces for oracles: admit many per theory, named
  8948 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8949 
  8950 * print_goals: optional output of const types (set show_consts and
  8951 show_types);
  8952 
  8953 * improved output of warnings (###) and errors (***);
  8954 
  8955 * subgoal_tac displays a warning if the new subgoal has type variables;
  8956 
  8957 * removed old README and Makefiles;
  8958 
  8959 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8960 
  8961 * removed obsolete init_pps and init_database;
  8962 
  8963 * deleted the obsolete tactical STATE, which was declared by
  8964     fun STATE tacfun st = tacfun st st;
  8965 
  8966 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8967 (which abbreviates $HOME);
  8968 
  8969 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8970 use isatool fixseq to adapt your ML programs (this works for fully
  8971 qualified references to the Sequence structure only!);
  8972 
  8973 * use_thy no longer requires writable current directory; it always
  8974 reloads .ML *and* .thy file, if either one is out of date;
  8975 
  8976 
  8977 *** Classical Reasoner ***
  8978 
  8979 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8980 tactics that use classical reasoning to simplify a subgoal without
  8981 splitting it into several subgoals;
  8982 
  8983 * Safe_tac: like safe_tac but uses the default claset;
  8984 
  8985 
  8986 *** Simplifier ***
  8987 
  8988 * added simplification meta rules:
  8989     (asm_)(full_)simplify: simpset -> thm -> thm;
  8990 
  8991 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8992 logics (again);
  8993 
  8994 * added prems argument to simplification procedures;
  8995 
  8996 * HOL, FOL, ZF: added infix function `addsplits':
  8997   instead of `<simpset> setloop (split_tac <thms>)'
  8998   you can simply write `<simpset> addsplits <thms>'
  8999 
  9000 
  9001 *** Syntax ***
  9002 
  9003 * TYPE('a) syntax for type reflection terms;
  9004 
  9005 * no longer handles consts with name "" -- declare as 'syntax' instead;
  9006 
  9007 * pretty printer: changed order of mixfix annotation preference (again!);
  9008 
  9009 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  9010 
  9011 
  9012 *** HOL ***
  9013 
  9014 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9015   with `addloop' of the simplifier to faciliate case splitting in premises.
  9016 
  9017 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  9018 
  9019 * HOL/Auth: new protocol proofs including some for the Internet
  9020   protocol TLS;
  9021 
  9022 * HOL/Map: new theory of `maps' a la VDM;
  9023 
  9024 * HOL/simplifier: simplification procedures nat_cancel_sums for
  9025 cancelling out common nat summands from =, <, <= (in)equalities, or
  9026 differences; simplification procedures nat_cancel_factor for
  9027 cancelling common factor from =, <, <= (in)equalities over natural
  9028 sums; nat_cancel contains both kinds of procedures, it is installed by
  9029 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  9030 
  9031 * HOL/simplifier: terms of the form
  9032   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  9033   are rewritten to
  9034   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  9035   and those of the form
  9036   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  9037   are rewritten to
  9038   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  9039 
  9040 * HOL/datatype
  9041   Each datatype `t' now comes with a theorem `split_t_case' of the form
  9042 
  9043   P(t_case f1 ... fn x) =
  9044      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  9045         ...
  9046        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  9047      )
  9048 
  9049   and a theorem `split_t_case_asm' of the form
  9050 
  9051   P(t_case f1 ... fn x) =
  9052     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  9053         ...
  9054        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  9055      )
  9056   which can be added to a simpset via `addsplits'. The existing theorems
  9057   expand_list_case and expand_option_case have been renamed to
  9058   split_list_case and split_option_case.
  9059 
  9060 * HOL/Arithmetic:
  9061   - `pred n' is automatically converted to `n-1'.
  9062     Users are strongly encouraged not to use `pred' any longer,
  9063     because it will disappear altogether at some point.
  9064   - Users are strongly encouraged to write "0 < n" rather than
  9065     "n ~= 0". Theorems and proof tools have been modified towards this
  9066     `standard'.
  9067 
  9068 * HOL/Lists:
  9069   the function "set_of_list" has been renamed "set" (and its theorems too);
  9070   the function "nth" now takes its arguments in the reverse order and
  9071   has acquired the infix notation "!" as in "xs!n".
  9072 
  9073 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  9074 
  9075 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  9076   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  9077 
  9078 * HOL/record: extensible records with schematic structural subtyping
  9079 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  9080 still lacks various theorems and concrete record syntax;
  9081 
  9082 
  9083 *** HOLCF ***
  9084 
  9085 * removed "axioms" and "generated by" sections;
  9086 
  9087 * replaced "ops" section by extended "consts" section, which is capable of
  9088   handling the continuous function space "->" directly;
  9089 
  9090 * domain package:
  9091   . proves theorems immediately and stores them in the theory,
  9092   . creates hierachical name space,
  9093   . now uses normal mixfix annotations (instead of cinfix...),
  9094   . minor changes to some names and values (for consistency),
  9095   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  9096   . separator between mutual domain defs: changed "," to "and",
  9097   . improved handling of sort constraints;  now they have to
  9098     appear on the left-hand side of the equations only;
  9099 
  9100 * fixed LAM <x,y,zs>.b syntax;
  9101 
  9102 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  9103 adm (%x. P (t x)), where P is chainfinite and t continuous;
  9104 
  9105 
  9106 *** FOL and ZF ***
  9107 
  9108 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9109   with `addloop' of the simplifier to faciliate case splitting in premises.
  9110 
  9111 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  9112 in HOL, they strip ALL and --> from proved theorems;
  9113 
  9114 
  9115 
  9116 New in Isabelle94-8 (May 1997)
  9117 ------------------------------
  9118 
  9119 *** General Changes ***
  9120 
  9121 * new utilities to build / run / maintain Isabelle etc. (in parts
  9122 still somewhat experimental); old Makefiles etc. still functional;
  9123 
  9124 * new 'Isabelle System Manual';
  9125 
  9126 * INSTALL text, together with ./configure and ./build scripts;
  9127 
  9128 * reimplemented type inference for greater efficiency, better error
  9129 messages and clean internal interface;
  9130 
  9131 * prlim command for dealing with lots of subgoals (an easier way of
  9132 setting goals_limit);
  9133 
  9134 
  9135 *** Syntax ***
  9136 
  9137 * supports alternative (named) syntax tables (parser and pretty
  9138 printer); internal interface is provided by add_modesyntax(_i);
  9139 
  9140 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  9141 be used in conjunction with the Isabelle symbol font; uses the
  9142 "symbols" syntax table;
  9143 
  9144 * added token_translation interface (may translate name tokens in
  9145 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  9146 the current print_mode); IMPORTANT: user print translation functions
  9147 are responsible for marking newly introduced bounds
  9148 (Syntax.mark_boundT);
  9149 
  9150 * token translations for modes "xterm" and "xterm_color" that display
  9151 names in bold, underline etc. or colors (which requires a color
  9152 version of xterm);
  9153 
  9154 * infixes may now be declared with names independent of their syntax;
  9155 
  9156 * added typed_print_translation (like print_translation, but may
  9157 access type of constant);
  9158 
  9159 
  9160 *** Classical Reasoner ***
  9161 
  9162 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  9163 some limitations.  Blast_tac...
  9164   + ignores addss, addbefore, addafter; this restriction is intrinsic
  9165   + ignores elimination rules that don't have the correct format
  9166         (the conclusion MUST be a formula variable)
  9167   + ignores types, which can make HOL proofs fail
  9168   + rules must not require higher-order unification, e.g. apply_type in ZF
  9169     [message "Function Var's argument not a bound variable" relates to this]
  9170   + its proof strategy is more general but can actually be slower
  9171 
  9172 * substitution with equality assumptions no longer permutes other
  9173 assumptions;
  9174 
  9175 * minor changes in semantics of addafter (now called addaltern); renamed
  9176 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  9177 (and access functions for it);
  9178 
  9179 * improved combination of classical reasoner and simplifier:
  9180   + functions for handling clasimpsets
  9181   + improvement of addss: now the simplifier is called _after_ the
  9182     safe steps.
  9183   + safe variant of addss called addSss: uses safe simplifications
  9184     _during_ the safe steps. It is more complete as it allows multiple
  9185     instantiations of unknowns (e.g. with slow_tac).
  9186 
  9187 *** Simplifier ***
  9188 
  9189 * added interface for simplification procedures (functions that
  9190 produce *proven* rewrite rules on the fly, depending on current
  9191 redex);
  9192 
  9193 * ordering on terms as parameter (used for ordered rewriting);
  9194 
  9195 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  9196 
  9197 * the solver is now split into a safe and an unsafe part.
  9198 This should be invisible for the normal user, except that the
  9199 functions setsolver and addsolver have been renamed to setSolver and
  9200 addSolver; added safe_asm_full_simp_tac;
  9201 
  9202 
  9203 *** HOL ***
  9204 
  9205 * a generic induction tactic `induct_tac' which works for all datatypes and
  9206 also for type `nat';
  9207 
  9208 * a generic case distinction tactic `exhaust_tac' which works for all
  9209 datatypes and also for type `nat';
  9210 
  9211 * each datatype comes with a function `size';
  9212 
  9213 * patterns in case expressions allow tuple patterns as arguments to
  9214 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  9215 
  9216 * primrec now also works with type nat;
  9217 
  9218 * recdef: a new declaration form, allows general recursive functions to be
  9219 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  9220 
  9221 * the constant for negation has been renamed from "not" to "Not" to
  9222 harmonize with FOL, ZF, LK, etc.;
  9223 
  9224 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  9225 infinite lists;
  9226 
  9227 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  9228 
  9229 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  9230 problems in commutative rings, using axiomatic type classes for + and *;
  9231 
  9232 * more examples in HOL/MiniML and HOL/Auth;
  9233 
  9234 * more default rewrite rules for quantifiers, union/intersection;
  9235 
  9236 * a new constant `arbitrary == @x.False';
  9237 
  9238 * HOLCF/IOA replaces old HOL/IOA;
  9239 
  9240 * HOLCF changes: derived all rules and arities
  9241   + axiomatic type classes instead of classes
  9242   + typedef instead of faking type definitions
  9243   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  9244   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  9245   + eliminated the types void, one, tr
  9246   + use unit lift and bool lift (with translations) instead of one and tr
  9247   + eliminated blift from Lift3.thy (use Def instead of blift)
  9248   all eliminated rules are derived as theorems --> no visible changes ;
  9249 
  9250 
  9251 *** ZF ***
  9252 
  9253 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  9254 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  9255 as ZF_cs addSIs [equalityI];
  9256 
  9257 
  9258 
  9259 New in Isabelle94-7 (November 96)
  9260 ---------------------------------
  9261 
  9262 * allowing negative levels (as offsets) in prlev and choplev;
  9263 
  9264 * super-linear speedup for large simplifications;
  9265 
  9266 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  9267 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  9268 FAIL); can suppress it using the command Delsimps (ex_simps @
  9269 all_simps); De Morgan laws are also now included, by default;
  9270 
  9271 * improved printing of ==>  :  ~:
  9272 
  9273 * new object-logic "Sequents" adds linear logic, while replacing LK
  9274 and Modal (thanks to Sara Kalvala);
  9275 
  9276 * HOL/Auth: correctness proofs for authentication protocols;
  9277 
  9278 * HOL: new auto_tac combines rewriting and classical reasoning (many
  9279 examples on HOL/Auth);
  9280 
  9281 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  9282 the rewriter and classical reasoner simultaneously;
  9283 
  9284 * function uresult no longer returns theorems in "standard" format;
  9285 regain previous version by: val uresult = standard o uresult;
  9286 
  9287 
  9288 
  9289 New in Isabelle94-6
  9290 -------------------
  9291 
  9292 * oracles -- these establish an interface between Isabelle and trusted
  9293 external reasoners, which may deliver results as theorems;
  9294 
  9295 * proof objects (in particular record all uses of oracles);
  9296 
  9297 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  9298 
  9299 * "constdefs" section in theory files;
  9300 
  9301 * "primrec" section (HOL) no longer requires names;
  9302 
  9303 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  9304 
  9305 
  9306 
  9307 New in Isabelle94-5
  9308 -------------------
  9309 
  9310 * reduced space requirements;
  9311 
  9312 * automatic HTML generation from theories;
  9313 
  9314 * theory files no longer require "..." (quotes) around most types;
  9315 
  9316 * new examples, including two proofs of the Church-Rosser theorem;
  9317 
  9318 * non-curried (1994) version of HOL is no longer distributed;
  9319 
  9320 
  9321 
  9322 New in Isabelle94-4
  9323 -------------------
  9324 
  9325 * greatly reduced space requirements;
  9326 
  9327 * theory files (.thy) no longer require \...\ escapes at line breaks;
  9328 
  9329 * searchable theorem database (see the section "Retrieving theorems" on
  9330 page 8 of the Reference Manual);
  9331 
  9332 * new examples, including Grabczewski's monumental case study of the
  9333 Axiom of Choice;
  9334 
  9335 * The previous version of HOL renamed to Old_HOL;
  9336 
  9337 * The new version of HOL (previously called CHOL) uses a curried syntax
  9338 for functions.  Application looks like f a b instead of f(a,b);
  9339 
  9340 * Mutually recursive inductive definitions finally work in HOL;
  9341 
  9342 * In ZF, pattern-matching on tuples is now available in all abstractions and
  9343 translates to the operator "split";
  9344 
  9345 
  9346 
  9347 New in Isabelle94-3
  9348 -------------------
  9349 
  9350 * new infix operator, addss, allowing the classical reasoner to
  9351 perform simplification at each step of its search.  Example:
  9352         fast_tac (cs addss ss)
  9353 
  9354 * a new logic, CHOL, the same as HOL, but with a curried syntax
  9355 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  9356 look like (a,b) instead of <a,b>;
  9357 
  9358 * PLEASE NOTE: CHOL will eventually replace HOL!
  9359 
  9360 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  9361 It translates to the operator "split".  A new theory of integers is available;
  9362 
  9363 * In ZF, integer numerals now denote two's-complement binary integers.
  9364 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  9365 
  9366 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  9367 of the Axiom of Choice;
  9368 
  9369 
  9370 
  9371 New in Isabelle94-2
  9372 -------------------
  9373 
  9374 * Significantly faster resolution;
  9375 
  9376 * the different sections in a .thy file can now be mixed and repeated
  9377 freely;
  9378 
  9379 * Database of theorems for FOL, HOL and ZF.  New
  9380 commands including qed, qed_goal and bind_thm store theorems in the database.
  9381 
  9382 * Simple database queries: return a named theorem (get_thm) or all theorems of
  9383 a given theory (thms_of), or find out what theory a theorem was proved in
  9384 (theory_of_thm);
  9385 
  9386 * Bugs fixed in the inductive definition and datatype packages;
  9387 
  9388 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  9389 and HOL_dup_cs obsolete;
  9390 
  9391 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  9392 have been removed;
  9393 
  9394 * Simpler definition of function space in ZF;
  9395 
  9396 * new results about cardinal and ordinal arithmetic in ZF;
  9397 
  9398 * 'subtype' facility in HOL for introducing new types as subsets of existing
  9399 types;
  9400 
  9401 :mode=text:wrap=hard:maxLineLen=72: