NEWS
author blanchet
Wed, 18 Apr 2012 22:40:25 +0200
changeset 48434 01f687b84aff
parent 48419 10c92d6a3caf
child 48438 407cabf66f21
permissions -rw-r--r--
Sledgehammer NEWS and CONTRIBUTORS
     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 * Finite_Set.fold now qualified.  INCOMPATIBILITY.
   304 
   305 * Consolidated theorem names concerning fold combinators:
   306 
   307   inf_INFI_fold_inf ~> inf_INF_fold_inf
   308   sup_SUPR_fold_sup ~> sup_SUP_fold_sup
   309   INFI_fold_inf ~> INF_fold_inf
   310   SUPR_fold_sup ~> SUP_fold_sup
   311   union_set ~> union_set_fold
   312   minus_set ~> minus_set_fold
   313   INFI_set_fold ~> INF_set_fold
   314   SUPR_set_fold ~> SUP_set_fold
   315   INF_code ~> INF_set_foldr
   316   SUP_code ~> SUP_set_foldr
   317   foldr.simps ~> foldr.simps (in point-free formulation)
   318   foldr_fold_rev ~> foldr_conv_fold
   319   foldl_fold ~> foldl_conv_fold
   320   foldr_foldr ~> foldr_conv_foldl
   321   foldl_foldr ~> foldl_conv_foldr
   322   fold_set_remdups ~> fold_set_fold_remdups
   323   fold_set ~> fold_set_fold
   324   fold1_set ~> fold1_set_fold
   325 
   326 INCOMPATIBILITY.
   327 
   328 * Dropped rarely useful theorems concerning fold combinators:
   329 foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
   330 rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
   331 concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
   332 foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
   333 listsum_conv_fold, listsum_foldl, sort_foldl_insort, foldl_assoc,
   334 foldr_conv_foldl, start_le_sum, elem_le_sum, sum_eq_0_conv.
   335 INCOMPATIBILITY.  For the common phrases "%xs. List.foldr plus xs 0"
   336 and "List.foldl plus 0", prefer "List.listsum".  Otherwise it can be
   337 useful to boil down "List.foldr" and "List.foldl" to "List.fold" by
   338 unfolding "foldr_conv_fold" and "foldl_conv_fold".
   339 
   340 * Dropped lemmas minus_set_foldr, union_set_foldr, union_coset_foldr,
   341 inter_coset_foldr, Inf_fin_set_foldr, Sup_fin_set_foldr,
   342 Min_fin_set_foldr, Max_fin_set_foldr, Inf_set_foldr, Sup_set_foldr,
   343 INF_set_foldr, SUP_set_foldr.  INCOMPATIBILITY.  Prefer corresponding
   344 lemmas over fold rather than foldr, or make use of lemmas
   345 fold_conv_foldr and fold_rev.
   346 
   347 * Congruence rules Option.map_cong and Option.bind_cong for recursion
   348 through option types.
   349 
   350 * Concrete syntax for case expressions includes constraints for source
   351 positions, and thus produces Prover IDE markup for its bindings.
   352 INCOMPATIBILITY for old-style syntax translations that augment the
   353 pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of
   354 one_case.
   355 
   356 * Discontinued configuration option "syntax_positions": atomic terms
   357 in parse trees are always annotated by position constraints.
   358 
   359 * New theory HOL/Library/DAList provides an abstract type for
   360 association lists with distinct keys.
   361 
   362 * 'datatype' specifications allow explicit sort constraints.
   363 
   364 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
   365 use theory HOL/Library/Nat_Bijection instead.
   366 
   367 * Theory HOL/Library/RBT_Impl: Backing implementation of red-black
   368 trees is now inside a type class context.  Names of affected
   369 operations and lemmas have been prefixed by rbt_.  INCOMPATIBILITY for
   370 theories working directly with raw red-black trees, adapt the names as
   371 follows:
   372 
   373   Operations:
   374   bulkload -> rbt_bulkload
   375   del_from_left -> rbt_del_from_left
   376   del_from_right -> rbt_del_from_right
   377   del -> rbt_del
   378   delete -> rbt_delete
   379   ins -> rbt_ins
   380   insert -> rbt_insert
   381   insertw -> rbt_insert_with
   382   insert_with_key -> rbt_insert_with_key
   383   map_entry -> rbt_map_entry
   384   lookup -> rbt_lookup
   385   sorted -> rbt_sorted
   386   tree_greater -> rbt_greater
   387   tree_less -> rbt_less
   388   tree_less_symbol -> rbt_less_symbol
   389   union -> rbt_union
   390   union_with -> rbt_union_with
   391   union_with_key -> rbt_union_with_key
   392 
   393   Lemmas:
   394   balance_left_sorted -> balance_left_rbt_sorted
   395   balance_left_tree_greater -> balance_left_rbt_greater
   396   balance_left_tree_less -> balance_left_rbt_less
   397   balance_right_sorted -> balance_right_rbt_sorted
   398   balance_right_tree_greater -> balance_right_rbt_greater
   399   balance_right_tree_less -> balance_right_rbt_less
   400   balance_sorted -> balance_rbt_sorted
   401   balance_tree_greater -> balance_rbt_greater
   402   balance_tree_less -> balance_rbt_less
   403   bulkload_is_rbt -> rbt_bulkload_is_rbt
   404   combine_sorted -> combine_rbt_sorted
   405   combine_tree_greater -> combine_rbt_greater
   406   combine_tree_less -> combine_rbt_less
   407   delete_in_tree -> rbt_delete_in_tree
   408   delete_is_rbt -> rbt_delete_is_rbt
   409   del_from_left_tree_greater -> rbt_del_from_left_rbt_greater
   410   del_from_left_tree_less -> rbt_del_from_left_rbt_less
   411   del_from_right_tree_greater -> rbt_del_from_right_rbt_greater
   412   del_from_right_tree_less -> rbt_del_from_right_rbt_less
   413   del_in_tree -> rbt_del_in_tree
   414   del_inv1_inv2 -> rbt_del_inv1_inv2
   415   del_sorted -> rbt_del_rbt_sorted
   416   del_tree_greater -> rbt_del_rbt_greater
   417   del_tree_less -> rbt_del_rbt_less
   418   dom_lookup_Branch -> dom_rbt_lookup_Branch
   419   entries_lookup -> entries_rbt_lookup
   420   finite_dom_lookup -> finite_dom_rbt_lookup
   421   insert_sorted -> rbt_insert_rbt_sorted
   422   insertw_is_rbt -> rbt_insertw_is_rbt
   423   insertwk_is_rbt -> rbt_insertwk_is_rbt
   424   insertwk_sorted -> rbt_insertwk_rbt_sorted
   425   insertw_sorted -> rbt_insertw_rbt_sorted
   426   ins_sorted -> ins_rbt_sorted
   427   ins_tree_greater -> ins_rbt_greater
   428   ins_tree_less -> ins_rbt_less
   429   is_rbt_sorted -> is_rbt_rbt_sorted
   430   lookup_balance -> rbt_lookup_balance
   431   lookup_bulkload -> rbt_lookup_rbt_bulkload
   432   lookup_delete -> rbt_lookup_rbt_delete
   433   lookup_Empty -> rbt_lookup_Empty
   434   lookup_from_in_tree -> rbt_lookup_from_in_tree
   435   lookup_in_tree -> rbt_lookup_in_tree
   436   lookup_ins -> rbt_lookup_ins
   437   lookup_insert -> rbt_lookup_rbt_insert
   438   lookup_insertw -> rbt_lookup_rbt_insertw
   439   lookup_insertwk -> rbt_lookup_rbt_insertwk
   440   lookup_keys -> rbt_lookup_keys
   441   lookup_map -> rbt_lookup_map
   442   lookup_map_entry -> rbt_lookup_rbt_map_entry
   443   lookup_tree_greater -> rbt_lookup_rbt_greater
   444   lookup_tree_less -> rbt_lookup_rbt_less
   445   lookup_union -> rbt_lookup_rbt_union
   446   map_entry_color_of -> rbt_map_entry_color_of
   447   map_entry_inv1 -> rbt_map_entry_inv1
   448   map_entry_inv2 -> rbt_map_entry_inv2
   449   map_entry_is_rbt -> rbt_map_entry_is_rbt
   450   map_entry_sorted -> rbt_map_entry_rbt_sorted
   451   map_entry_tree_greater -> rbt_map_entry_rbt_greater
   452   map_entry_tree_less -> rbt_map_entry_rbt_less
   453   map_tree_greater -> map_rbt_greater
   454   map_tree_less -> map_rbt_less
   455   map_sorted -> map_rbt_sorted
   456   paint_sorted -> paint_rbt_sorted
   457   paint_lookup -> paint_rbt_lookup
   458   paint_tree_greater -> paint_rbt_greater
   459   paint_tree_less -> paint_rbt_less
   460   sorted_entries -> rbt_sorted_entries
   461   tree_greater_eq_trans -> rbt_greater_eq_trans
   462   tree_greater_nit -> rbt_greater_nit
   463   tree_greater_prop -> rbt_greater_prop
   464   tree_greater_simps -> rbt_greater_simps
   465   tree_greater_trans -> rbt_greater_trans
   466   tree_less_eq_trans -> rbt_less_eq_trans
   467   tree_less_nit -> rbt_less_nit
   468   tree_less_prop -> rbt_less_prop
   469   tree_less_simps -> rbt_less_simps
   470   tree_less_trans -> rbt_less_trans
   471   tree_ord_props -> rbt_ord_props
   472   union_Branch -> rbt_union_Branch
   473   union_is_rbt -> rbt_union_is_rbt
   474   unionw_is_rbt -> rbt_unionw_is_rbt
   475   unionwk_is_rbt -> rbt_unionwk_is_rbt
   476   unionwk_sorted -> rbt_unionwk_rbt_sorted
   477 
   478 * Session HOL-Word: Discontinued many redundant theorems specific to
   479 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
   480 instead.
   481 
   482   word_sub_alt ~> word_sub_wi
   483   word_add_alt ~> word_add_def
   484   word_mult_alt ~> word_mult_def
   485   word_minus_alt ~> word_minus_def
   486   word_0_alt ~> word_0_wi
   487   word_1_alt ~> word_1_wi
   488   word_add_0 ~> add_0_left
   489   word_add_0_right ~> add_0_right
   490   word_mult_1 ~> mult_1_left
   491   word_mult_1_right ~> mult_1_right
   492   word_add_commute ~> add_commute
   493   word_add_assoc ~> add_assoc
   494   word_add_left_commute ~> add_left_commute
   495   word_mult_commute ~> mult_commute
   496   word_mult_assoc ~> mult_assoc
   497   word_mult_left_commute ~> mult_left_commute
   498   word_left_distrib ~> left_distrib
   499   word_right_distrib ~> right_distrib
   500   word_left_minus ~> left_minus
   501   word_diff_0_right ~> diff_0_right
   502   word_diff_self ~> diff_self
   503   word_sub_def ~> diff_minus
   504   word_diff_minus ~> diff_minus
   505   word_add_ac ~> add_ac
   506   word_mult_ac ~> mult_ac
   507   word_plus_ac0 ~> add_0_left add_0_right add_ac
   508   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
   509   word_order_trans ~> order_trans
   510   word_order_refl ~> order_refl
   511   word_order_antisym ~> order_antisym
   512   word_order_linear ~> linorder_linear
   513   lenw1_zero_neq_one ~> zero_neq_one
   514   word_number_of_eq ~> number_of_eq
   515   word_of_int_add_hom ~> wi_hom_add
   516   word_of_int_sub_hom ~> wi_hom_sub
   517   word_of_int_mult_hom ~> wi_hom_mult
   518   word_of_int_minus_hom ~> wi_hom_neg
   519   word_of_int_succ_hom ~> wi_hom_succ
   520   word_of_int_pred_hom ~> wi_hom_pred
   521   word_of_int_0_hom ~> word_0_wi
   522   word_of_int_1_hom ~> word_1_wi
   523 
   524 * Clarified attribute "mono_set": pure declaration without modifying
   525 the result of the fact expression.
   526 
   527 * "Transitive_Closure.ntrancl": bounded transitive closure on
   528 relations.
   529 
   530 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
   531 
   532 * Theory Int: Discontinued many legacy theorems specific to type int.
   533 INCOMPATIBILITY, use the corresponding generic theorems instead.
   534 
   535   zminus_zminus ~> minus_minus
   536   zminus_0 ~> minus_zero
   537   zminus_zadd_distrib ~> minus_add_distrib
   538   zadd_commute ~> add_commute
   539   zadd_assoc ~> add_assoc
   540   zadd_left_commute ~> add_left_commute
   541   zadd_ac ~> add_ac
   542   zmult_ac ~> mult_ac
   543   zadd_0 ~> add_0_left
   544   zadd_0_right ~> add_0_right
   545   zadd_zminus_inverse2 ~> left_minus
   546   zmult_zminus ~> mult_minus_left
   547   zmult_commute ~> mult_commute
   548   zmult_assoc ~> mult_assoc
   549   zadd_zmult_distrib ~> left_distrib
   550   zadd_zmult_distrib2 ~> right_distrib
   551   zdiff_zmult_distrib ~> left_diff_distrib
   552   zdiff_zmult_distrib2 ~> right_diff_distrib
   553   zmult_1 ~> mult_1_left
   554   zmult_1_right ~> mult_1_right
   555   zle_refl ~> order_refl
   556   zle_trans ~> order_trans
   557   zle_antisym ~> order_antisym
   558   zle_linear ~> linorder_linear
   559   zless_linear ~> linorder_less_linear
   560   zadd_left_mono ~> add_left_mono
   561   zadd_strict_right_mono ~> add_strict_right_mono
   562   zadd_zless_mono ~> add_less_le_mono
   563   int_0_less_1 ~> zero_less_one
   564   int_0_neq_1 ~> zero_neq_one
   565   zless_le ~> less_le
   566   zpower_zadd_distrib ~> power_add
   567   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   568   zero_le_zpower_abs ~> zero_le_power_abs
   569 
   570 * Theory Deriv: Renamed
   571 
   572   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   573 
   574 * New "case_product" attribute to generate a case rule doing multiple
   575 case distinctions at the same time.  E.g.
   576 
   577   list.exhaust [case_product nat.exhaust]
   578 
   579 produces a rule which can be used to perform case distinction on both
   580 a list and a nat.
   581 
   582 * Theory Library/Multiset: Improved code generation of multisets.
   583 
   584 * New diagnostic command 'find_unused_assms' to find potentially
   585 superfluous assumptions in theorems using Quickcheck.
   586 
   587 * Quickcheck:
   588 
   589   - Quickcheck returns variable assignments as counterexamples, which
   590     allows to reveal the underspecification of functions under test.
   591     For example, refuting "hd xs = x", it presents the variable
   592     assignment xs = [] and x = a1 as a counterexample, assuming that
   593     any property is false whenever "hd []" occurs in it.
   594 
   595     These counterexample are marked as potentially spurious, as
   596     Quickcheck also returns "xs = []" as a counterexample to the
   597     obvious theorem "hd xs = hd xs".
   598 
   599     After finding a potentially spurious counterexample, Quickcheck
   600     continues searching for genuine ones.
   601 
   602     By default, Quickcheck shows potentially spurious and genuine
   603     counterexamples. The option "genuine_only" sets quickcheck to only
   604     show genuine counterexamples.
   605 
   606   - The command 'quickcheck_generator' creates random and exhaustive
   607     value generators for a given type and operations.
   608 
   609     It generates values by using the operations as if they were
   610     constructors of that type.
   611 
   612   - Support for multisets.
   613 
   614   - Added "use_subtype" options.
   615 
   616   - Added "quickcheck_locale" configuration to specify how to process
   617     conjectures in a locale context.
   618 
   619 * Nitpick:
   620   - Fixed infinite loop caused by the 'peephole_optim' option and
   621     affecting 'rat' and 'real'.
   622 
   623 * Sledgehammer:
   624   - Integrated more tightly with SPASS, as described in the ITP 2012 paper "More
   625     SPASS with Isabelle".
   626   - Made it try "smt" as a fallback if "metis" fails or times out.
   627   - Added support for the following provers: Alt-Ergo (via Why3 and TFF1),
   628     iProver, iProver-Eq.
   629   - Replaced remote E-SInE with remote Satallax in the default setup.
   630   - Sped up the minimizer.
   631   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   632   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   633   - Renamed "sound" option to "strict".
   634 
   635 * Metis:
   636   - Added possibility to specify lambda translations scheme as a
   637     parenthesized argument (e.g., "by (metis (lifting) ...)").
   638 
   639 * SMT:
   640   - Renamed "smt_fixed" option to "smt_read_only_certificates".
   641 
   642 * Command 'try0':
   643   - Renamed from 'try_methods'. INCOMPATIBILITY.
   644 
   645 * New "eventually_elim" method as a generalized variant of the
   646 eventually_elim* rules. Supports structured proofs.
   647 
   648 * HOL/TPTP: support to parse and import TPTP problems (all languages)
   649 into Isabelle/HOL.
   650 
   651 
   652 *** FOL ***
   653 
   654 * New "case_product" attribute (see HOL).
   655 
   656 
   657 *** ZF ***
   658 
   659 * Greater support for structured proofs involving induction or case
   660 analysis.
   661 
   662 * Much greater use of mathematical symbols.
   663 
   664 * Removal of many ML theorem bindings.  INCOMPATIBILITY.
   665 
   666 
   667 *** ML ***
   668 
   669 * Antiquotation @{keyword "name"} produces a parser for outer syntax
   670 from a minor keyword introduced via theory header declaration.
   671 
   672 * Antiquotation @{command_spec "name"} produces the
   673 Outer_Syntax.command_spec from a major keyword introduced via theory
   674 header declaration; it can be passed to Outer_Syntax.command etc.
   675 
   676 * Local_Theory.define no longer hard-wires default theorem name
   677 "foo_def", but retains the binding as given.  If that is Binding.empty
   678 / Attrib.empty_binding, the result is not registered as user-level
   679 fact.  The Local_Theory.define_internal variant allows to specify a
   680 non-empty name (used for the foundation in the background theory),
   681 while omitting the fact binding in the user-context.  Potential
   682 INCOMPATIBILITY for derived definitional packages: need to specify
   683 naming policy for primitive definitions more explicitly.
   684 
   685 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
   686 conformance with similar operations in structure Term and Logic.
   687 
   688 * Antiquotation @{attributes [...]} embeds attribute source
   689 representation into the ML text, which is particularly useful with
   690 declarations like Local_Theory.note.
   691 
   692 * Structure Proof_Context follows standard naming scheme.  Old
   693 ProofContext has been discontinued.  INCOMPATIBILITY.
   694 
   695 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   696 change of semantics: update is applied to auxiliary local theory
   697 context as well.
   698 
   699 * Modernized some old-style infix operations:
   700 
   701   addeqcongs    ~> Simplifier.add_eqcong
   702   deleqcongs    ~> Simplifier.del_eqcong
   703   addcongs      ~> Simplifier.add_cong
   704   delcongs      ~> Simplifier.del_cong
   705   setmksimps    ~> Simplifier.set_mksimps
   706   setmkcong     ~> Simplifier.set_mkcong
   707   setmksym      ~> Simplifier.set_mksym
   708   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   709   settermless   ~> Simplifier.set_termless
   710   setsubgoaler  ~> Simplifier.set_subgoaler
   711   addsplits     ~> Splitter.add_split
   712   delsplits     ~> Splitter.del_split
   713 
   714 
   715 *** System ***
   716 
   717 * ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
   718 (not just JRE).
   719 
   720 * ISABELLE_HOME_WINDOWS refers to ISABELLE_HOME in windows file name
   721 notation, which is useful for the jEdit file browser, for example.
   722 
   723 
   724 
   725 New in Isabelle2011-1 (October 2011)
   726 ------------------------------------
   727 
   728 *** General ***
   729 
   730 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   731 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   732 
   733   - Management of multiple theory files directly from the editor
   734     buffer store -- bypassing the file-system (no requirement to save
   735     files for checking).
   736 
   737   - Markup of formal entities within the text buffer, with semantic
   738     highlighting, tooltips and hyperlinks to jump to defining source
   739     positions.
   740 
   741   - Improved text rendering, with sub/superscripts in the source
   742     buffer (including support for copy/paste wrt. output panel, HTML
   743     theory output and other non-Isabelle text boxes).
   744 
   745   - Refined scheduling of proof checking and printing of results,
   746     based on interactive editor view.  (Note: jEdit folding and
   747     narrowing allows to restrict buffer perspectives explicitly.)
   748 
   749   - Reduced CPU performance requirements, usable on machines with few
   750     cores.
   751 
   752   - Reduced memory requirements due to pruning of unused document
   753     versions (garbage collection).
   754 
   755 See also ~~/src/Tools/jEdit/README.html for further information,
   756 including some remaining limitations.
   757 
   758 * Theory loader: source files are exclusively located via the master
   759 directory of each theory node (where the .thy file itself resides).
   760 The global load path (such as src/HOL/Library) has been discontinued.
   761 Note that the path element ~~ may be used to reference theories in the
   762 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   763 INCOMPATIBILITY.
   764 
   765 * Theory loader: source files are identified by content via SHA1
   766 digests.  Discontinued former path/modtime identification and optional
   767 ISABELLE_FILE_IDENT plugin scripts.
   768 
   769 * Parallelization of nested Isar proofs is subject to
   770 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   771 usedir option -Q.
   772 
   773 * Name space: former unsynchronized references are now proper
   774 configuration options, with more conventional names:
   775 
   776   long_names   ~> names_long
   777   short_names  ~> names_short
   778   unique_names ~> names_unique
   779 
   780 Minor INCOMPATIBILITY, need to declare options in context like this:
   781 
   782   declare [[names_unique = false]]
   783 
   784 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   785 that the result needs to be unique, which means fact specifications
   786 may have to be refined after enriching a proof context.
   787 
   788 * Attribute "case_names" has been refined: the assumptions in each case
   789 can be named now by following the case name with [name1 name2 ...].
   790 
   791 * Isabelle/Isar reference manual has been updated and extended:
   792   - "Synopsis" provides a catalog of main Isar language concepts.
   793   - Formal references in syntax diagrams, via @{rail} antiquotation.
   794   - Updated material from classic "ref" manual, notably about
   795     "Classical Reasoner".
   796 
   797 
   798 *** HOL ***
   799 
   800 * Class bot and top require underlying partial order rather than
   801 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   802 
   803 * Class complete_lattice: generalized a couple of lemmas from sets;
   804 generalized theorems INF_cong and SUP_cong.  New type classes for
   805 complete boolean algebras and complete linear orders.  Lemmas
   806 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   807 class complete_linorder.
   808 
   809 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   810 Sup_fun_def, Inf_apply, Sup_apply.
   811 
   812 Removed redundant lemmas (the right hand side gives hints how to
   813 replace them for (metis ...), or (simp only: ...) proofs):
   814 
   815   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   816   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   817   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   818   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   819   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   820   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   821   Inter_def ~> INF_def, image_def
   822   Union_def ~> SUP_def, image_def
   823   INT_eq ~> INF_def, and image_def
   824   UN_eq ~> SUP_def, and image_def
   825   INF_subset ~> INF_superset_mono [OF _ order_refl]
   826 
   827 More consistent and comprehensive names:
   828 
   829   INTER_eq_Inter_image ~> INF_def
   830   UNION_eq_Union_image ~> SUP_def
   831   INFI_def ~> INF_def
   832   SUPR_def ~> SUP_def
   833   INF_leI ~> INF_lower
   834   INF_leI2 ~> INF_lower2
   835   le_INFI ~> INF_greatest
   836   le_SUPI ~> SUP_upper
   837   le_SUPI2 ~> SUP_upper2
   838   SUP_leI ~> SUP_least
   839   INFI_bool_eq ~> INF_bool_eq
   840   SUPR_bool_eq ~> SUP_bool_eq
   841   INFI_apply ~> INF_apply
   842   SUPR_apply ~> SUP_apply
   843   INTER_def ~> INTER_eq
   844   UNION_def ~> UNION_eq
   845 
   846 INCOMPATIBILITY.
   847 
   848 * Renamed theory Complete_Lattice to Complete_Lattices.
   849 INCOMPATIBILITY.
   850 
   851 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   852 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   853 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   854 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   855 
   856 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   857 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   858 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   859 INCOMPATIBILITY.
   860 
   861 * Added syntactic classes "inf" and "sup" for the respective
   862 constants.  INCOMPATIBILITY: Changes in the argument order of the
   863 (mostly internal) locale predicates for some derived classes.
   864 
   865 * Theorem collections ball_simps and bex_simps do not contain theorems
   866 referring to UNION any longer; these have been moved to collection
   867 UN_ball_bex_simps.  INCOMPATIBILITY.
   868 
   869 * Theory Archimedean_Field: floor now is defined as parameter of a
   870 separate type class floor_ceiling.
   871 
   872 * Theory Finite_Set: more coherent development of fold_set locales:
   873 
   874     locale fun_left_comm ~> locale comp_fun_commute
   875     locale fun_left_comm_idem ~> locale comp_fun_idem
   876 
   877 Both use point-free characterization; interpretation proofs may need
   878 adjustment.  INCOMPATIBILITY.
   879 
   880 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   881 accordance with standard mathematical terminology. INCOMPATIBILITY.
   882 
   883 * Theory Complex_Main: The locale interpretations for the
   884 bounded_linear and bounded_bilinear locales have been removed, in
   885 order to reduce the number of duplicate lemmas. Users must use the
   886 original names for distributivity theorems, potential INCOMPATIBILITY.
   887 
   888   divide.add ~> add_divide_distrib
   889   divide.diff ~> diff_divide_distrib
   890   divide.setsum ~> setsum_divide_distrib
   891   mult.add_right ~> right_distrib
   892   mult.diff_right ~> right_diff_distrib
   893   mult_right.setsum ~> setsum_right_distrib
   894   mult_left.diff ~> left_diff_distrib
   895 
   896 * Theory Complex_Main: Several redundant theorems have been removed or
   897 replaced by more general versions. INCOMPATIBILITY.
   898 
   899   real_diff_def ~> minus_real_def
   900   real_divide_def ~> divide_real_def
   901   real_less_def ~> less_le
   902   real_abs_def ~> abs_real_def
   903   real_sgn_def ~> sgn_real_def
   904   real_mult_commute ~> mult_commute
   905   real_mult_assoc ~> mult_assoc
   906   real_mult_1 ~> mult_1_left
   907   real_add_mult_distrib ~> left_distrib
   908   real_zero_not_eq_one ~> zero_neq_one
   909   real_mult_inverse_left ~> left_inverse
   910   INVERSE_ZERO ~> inverse_zero
   911   real_le_refl ~> order_refl
   912   real_le_antisym ~> order_antisym
   913   real_le_trans ~> order_trans
   914   real_le_linear ~> linear
   915   real_le_eq_diff ~> le_iff_diff_le_0
   916   real_add_left_mono ~> add_left_mono
   917   real_mult_order ~> mult_pos_pos
   918   real_mult_less_mono2 ~> mult_strict_left_mono
   919   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   920   real_0_le_divide_iff ~> zero_le_divide_iff
   921   realpow_two_disj ~> power2_eq_iff
   922   real_squared_diff_one_factored ~> square_diff_one_factored
   923   realpow_two_diff ~> square_diff_square_factored
   924   reals_complete2 ~> complete_real
   925   real_sum_squared_expand ~> power2_sum
   926   exp_ln_eq ~> ln_unique
   927   expi_add ~> exp_add
   928   expi_zero ~> exp_zero
   929   lemma_DERIV_subst ~> DERIV_cong
   930   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   931   LIMSEQ_const ~> tendsto_const
   932   LIMSEQ_norm ~> tendsto_norm
   933   LIMSEQ_add ~> tendsto_add
   934   LIMSEQ_minus ~> tendsto_minus
   935   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   936   LIMSEQ_diff ~> tendsto_diff
   937   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   938   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   939   LIMSEQ_mult ~> tendsto_mult
   940   LIMSEQ_inverse ~> tendsto_inverse
   941   LIMSEQ_divide ~> tendsto_divide
   942   LIMSEQ_pow ~> tendsto_power
   943   LIMSEQ_setsum ~> tendsto_setsum
   944   LIMSEQ_setprod ~> tendsto_setprod
   945   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   946   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   947   LIMSEQ_imp_rabs ~> tendsto_rabs
   948   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   949   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   950   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   951   LIMSEQ_Complex ~> tendsto_Complex
   952   LIM_ident ~> tendsto_ident_at
   953   LIM_const ~> tendsto_const
   954   LIM_add ~> tendsto_add
   955   LIM_add_zero ~> tendsto_add_zero
   956   LIM_minus ~> tendsto_minus
   957   LIM_diff ~> tendsto_diff
   958   LIM_norm ~> tendsto_norm
   959   LIM_norm_zero ~> tendsto_norm_zero
   960   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   961   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   962   LIM_rabs ~> tendsto_rabs
   963   LIM_rabs_zero ~> tendsto_rabs_zero
   964   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   965   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   966   LIM_compose ~> tendsto_compose
   967   LIM_mult ~> tendsto_mult
   968   LIM_scaleR ~> tendsto_scaleR
   969   LIM_of_real ~> tendsto_of_real
   970   LIM_power ~> tendsto_power
   971   LIM_inverse ~> tendsto_inverse
   972   LIM_sgn ~> tendsto_sgn
   973   isCont_LIM_compose ~> isCont_tendsto_compose
   974   bounded_linear.LIM ~> bounded_linear.tendsto
   975   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   976   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   977   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   978   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   979   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   980   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   981 
   982 * Theory Complex_Main: The definition of infinite series was
   983 generalized.  Now it is defined on the type class {topological_space,
   984 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   985 
   986 * Theory Complex_Main: The complex exponential function "expi" is now
   987 a type-constrained abbreviation for "exp :: complex => complex"; thus
   988 several polymorphic lemmas about "exp" are now applicable to "expi".
   989 
   990 * Code generation:
   991 
   992   - Theory Library/Code_Char_ord provides native ordering of
   993     characters in the target language.
   994 
   995   - Commands code_module and code_library are legacy, use export_code
   996     instead.
   997 
   998   - Method "evaluation" is legacy, use method "eval" instead.
   999 
  1000   - Legacy evaluator "SML" is deactivated by default.  May be
  1001     reactivated by the following theory command:
  1002 
  1003       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
  1004 
  1005 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
  1006 
  1007 * New proof method "induction" that gives induction hypotheses the
  1008 name "IH", thus distinguishing them from further hypotheses that come
  1009 from rule induction.  The latter are still called "hyps".  Method
  1010 "induction" is a thin wrapper around "induct" and follows the same
  1011 syntax.
  1012 
  1013 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
  1014 still available as a legacy feature for some time.
  1015 
  1016 * Nitpick:
  1017   - Added "need" and "total_consts" options.
  1018   - Reintroduced "show_skolems" option by popular demand.
  1019   - Renamed attribute: nitpick_def ~> nitpick_unfold.
  1020     INCOMPATIBILITY.
  1021 
  1022 * Sledgehammer:
  1023   - Use quasi-sound (and efficient) translations by default.
  1024   - Added support for the following provers: E-ToFoF, LEO-II,
  1025     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
  1026   - Automatically preplay and minimize proofs before showing them if
  1027     this can be done within reasonable time.
  1028   - sledgehammer available_provers ~> sledgehammer supported_provers.
  1029     INCOMPATIBILITY.
  1030   - Added "preplay_timeout", "slicing", "type_enc", "sound",
  1031     "max_mono_iters", and "max_new_mono_instances" options.
  1032   - Removed "explicit_apply" and "full_types" options as well as "Full
  1033     Types" Proof General menu item. INCOMPATIBILITY.
  1034 
  1035 * Metis:
  1036   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
  1037   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
  1038     INCOMPATIBILITY.
  1039 
  1040 * Command 'try':
  1041   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
  1042     "elim:" options. INCOMPATIBILITY.
  1043   - Introduced 'try' that not only runs 'try_methods' but also
  1044     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
  1045 
  1046 * Quickcheck:
  1047   - Added "eval" option to evaluate terms for the found counterexample
  1048     (currently only supported by the default (exhaustive) tester).
  1049   - Added post-processing of terms to obtain readable counterexamples
  1050     (currently only supported by the default (exhaustive) tester).
  1051   - New counterexample generator quickcheck[narrowing] enables
  1052     narrowing-based testing.  Requires the Glasgow Haskell compiler
  1053     with its installation location defined in the Isabelle settings
  1054     environment as ISABELLE_GHC.
  1055   - Removed quickcheck tester "SML" based on the SML code generator
  1056     (formly in HOL/Library).
  1057 
  1058 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
  1059 use 'partial_function' instead.
  1060 
  1061 * Theory Library/Extended_Reals replaces now the positive extended
  1062 reals found in probability theory. This file is extended by
  1063 Multivariate_Analysis/Extended_Real_Limits.
  1064 
  1065 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
  1066 from where it must be imported explicitly if it is really required.
  1067 INCOMPATIBILITY.
  1068 
  1069 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
  1070 been moved here.  INCOMPATIBILITY.
  1071 
  1072 * Theory Library/Saturated provides type of numbers with saturated
  1073 arithmetic.
  1074 
  1075 * Theory Library/Product_Lattice defines a pointwise ordering for the
  1076 product type 'a * 'b, and provides instance proofs for various order
  1077 and lattice type classes.
  1078 
  1079 * Theory Library/Countable now provides the "countable_datatype" proof
  1080 method for proving "countable" class instances for datatypes.
  1081 
  1082 * Theory Library/Cset_Monad allows do notation for computable sets
  1083 (cset) via the generic monad ad-hoc overloading facility.
  1084 
  1085 * Library: Theories of common data structures are split into theories
  1086 for implementation, an invariant-ensuring type, and connection to an
  1087 abstract type. INCOMPATIBILITY.
  1088 
  1089   - RBT is split into RBT and RBT_Mapping.
  1090   - AssocList is split and renamed into AList and AList_Mapping.
  1091   - DList is split into DList_Impl, DList, and DList_Cset.
  1092   - Cset is split into Cset and List_Cset.
  1093 
  1094 * Theory Library/Nat_Infinity has been renamed to
  1095 Library/Extended_Nat, with name changes of the following types and
  1096 constants:
  1097 
  1098   type inat   ~> type enat
  1099   Fin         ~> enat
  1100   Infty       ~> infinity (overloaded)
  1101   iSuc        ~> eSuc
  1102   the_Fin     ~> the_enat
  1103 
  1104 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
  1105 been renamed accordingly. INCOMPATIBILITY.
  1106 
  1107 * Session Multivariate_Analysis: The euclidean_space type class now
  1108 fixes a constant "Basis :: 'a set" consisting of the standard
  1109 orthonormal basis for the type. Users now have the option of
  1110 quantifying over this set instead of using the "basis" function, e.g.
  1111 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
  1112 
  1113 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
  1114 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
  1115 "Cart_nth" and "Cart_lambda" have been respectively renamed to
  1116 "vec_nth" and "vec_lambda"; theorems mentioning those names have
  1117 changed to match. Definition theorems for overloaded constants now use
  1118 the standard "foo_vec_def" naming scheme. A few other theorems have
  1119 been renamed as follows (INCOMPATIBILITY):
  1120 
  1121   Cart_eq          ~> vec_eq_iff
  1122   dist_nth_le_cart ~> dist_vec_nth_le
  1123   tendsto_vector   ~> vec_tendstoI
  1124   Cauchy_vector    ~> vec_CauchyI
  1125 
  1126 * Session Multivariate_Analysis: Several duplicate theorems have been
  1127 removed, and other theorems have been renamed or replaced with more
  1128 general versions. INCOMPATIBILITY.
  1129 
  1130   finite_choice ~> finite_set_choice
  1131   eventually_conjI ~> eventually_conj
  1132   eventually_and ~> eventually_conj_iff
  1133   eventually_false ~> eventually_False
  1134   setsum_norm ~> norm_setsum
  1135   Lim_sequentially ~> LIMSEQ_def
  1136   Lim_ident_at ~> LIM_ident
  1137   Lim_const ~> tendsto_const
  1138   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
  1139   Lim_neg ~> tendsto_minus
  1140   Lim_add ~> tendsto_add
  1141   Lim_sub ~> tendsto_diff
  1142   Lim_mul ~> tendsto_scaleR
  1143   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
  1144   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
  1145   Lim_linear ~> bounded_linear.tendsto
  1146   Lim_component ~> tendsto_euclidean_component
  1147   Lim_component_cart ~> tendsto_vec_nth
  1148   Lim_inner ~> tendsto_inner [OF tendsto_const]
  1149   dot_lsum ~> inner_setsum_left
  1150   dot_rsum ~> inner_setsum_right
  1151   continuous_cmul ~> continuous_scaleR [OF continuous_const]
  1152   continuous_neg ~> continuous_minus
  1153   continuous_sub ~> continuous_diff
  1154   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
  1155   continuous_mul ~> continuous_scaleR
  1156   continuous_inv ~> continuous_inverse
  1157   continuous_at_within_inv ~> continuous_at_within_inverse
  1158   continuous_at_inv ~> continuous_at_inverse
  1159   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
  1160   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
  1161   continuous_at_component ~> continuous_component [OF continuous_at_id]
  1162   continuous_on_neg ~> continuous_on_minus
  1163   continuous_on_sub ~> continuous_on_diff
  1164   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
  1165   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
  1166   continuous_on_mul ~> continuous_on_scaleR
  1167   continuous_on_mul_real ~> continuous_on_mult
  1168   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
  1169   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
  1170   continuous_on_inverse ~> continuous_on_inv
  1171   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
  1172   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
  1173   subset_interior ~> interior_mono
  1174   subset_closure ~> closure_mono
  1175   closure_univ ~> closure_UNIV
  1176   real_arch_lt ~> reals_Archimedean2
  1177   real_arch ~> reals_Archimedean3
  1178   real_abs_norm ~> abs_norm_cancel
  1179   real_abs_sub_norm ~> norm_triangle_ineq3
  1180   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
  1181 
  1182 * Session HOL-Probability:
  1183   - Caratheodory's extension lemma is now proved for ring_of_sets.
  1184   - Infinite products of probability measures are now available.
  1185   - Sigma closure is independent, if the generator is independent
  1186   - Use extended reals instead of positive extended
  1187     reals. INCOMPATIBILITY.
  1188 
  1189 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
  1190 
  1191   expand_fun_below ~> fun_below_iff
  1192   below_fun_ext ~> fun_belowI
  1193   expand_cfun_eq ~> cfun_eq_iff
  1194   ext_cfun ~> cfun_eqI
  1195   expand_cfun_below ~> cfun_below_iff
  1196   below_cfun_ext ~> cfun_belowI
  1197   monofun_fun_fun ~> fun_belowD
  1198   monofun_fun_arg ~> monofunE
  1199   monofun_lub_fun ~> adm_monofun [THEN admD]
  1200   cont_lub_fun ~> adm_cont [THEN admD]
  1201   cont2cont_Rep_CFun ~> cont2cont_APP
  1202   cont_Rep_CFun_app ~> cont_APP_app
  1203   cont_Rep_CFun_app_app ~> cont_APP_app_app
  1204   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
  1205   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
  1206   contlub_cfun ~> lub_APP [symmetric]
  1207   contlub_LAM ~> lub_LAM [symmetric]
  1208   thelubI ~> lub_eqI
  1209   UU_I ~> bottomI
  1210   lift_distinct1 ~> lift.distinct(1)
  1211   lift_distinct2 ~> lift.distinct(2)
  1212   Def_not_UU ~> lift.distinct(2)
  1213   Def_inject ~> lift.inject
  1214   below_UU_iff ~> below_bottom_iff
  1215   eq_UU_iff ~> eq_bottom_iff
  1216 
  1217 
  1218 *** Document preparation ***
  1219 
  1220 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
  1221 isar-ref manual, both for description and actual application of the
  1222 same.
  1223 
  1224 * Antiquotation @{value} evaluates the given term and presents its
  1225 result.
  1226 
  1227 * Antiquotations: term style "isub" provides ad-hoc conversion of
  1228 variables x1, y23 into subscripted form x\<^isub>1,
  1229 y\<^isub>2\<^isub>3.
  1230 
  1231 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
  1232 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
  1233 
  1234 * Localized \isabellestyle switch can be used within blocks or groups
  1235 like this:
  1236 
  1237   \isabellestyle{it}  %preferred default
  1238   {\isabellestylett @{text "typewriter stuff"}}
  1239 
  1240 * Discontinued special treatment of hard tabulators.  Implicit
  1241 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
  1242 layouts.
  1243 
  1244 
  1245 *** ML ***
  1246 
  1247 * The inner syntax of sort/type/term/prop supports inlined YXML
  1248 representations within quoted string tokens.  By encoding logical
  1249 entities via Term_XML (in ML or Scala) concrete syntax can be
  1250 bypassed, which is particularly useful for producing bits of text
  1251 under external program control.
  1252 
  1253 * Antiquotations for ML and document preparation are managed as theory
  1254 data, which requires explicit setup.
  1255 
  1256 * Isabelle_Process.is_active allows tools to check if the official
  1257 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
  1258 (better known as Proof General).
  1259 
  1260 * Structure Proof_Context follows standard naming scheme.  Old
  1261 ProofContext is still available for some time as legacy alias.
  1262 
  1263 * Structure Timing provides various operations for timing; supersedes
  1264 former start_timing/end_timing etc.
  1265 
  1266 * Path.print is the official way to show file-system paths to users
  1267 (including quotes etc.).
  1268 
  1269 * Inner syntax: identifiers in parse trees of generic categories
  1270 "logic", "aprop", "idt" etc. carry position information (disguised as
  1271 type constraints).  Occasional INCOMPATIBILITY with non-compliant
  1272 translations that choke on unexpected type constraints.  Positions can
  1273 be stripped in ML translations via Syntax.strip_positions /
  1274 Syntax.strip_positions_ast, or via the syntax constant
  1275 "_strip_positions" within parse trees.  As last resort, positions can
  1276 be disabled via the configuration option Syntax.positions, which is
  1277 called "syntax_positions" in Isar attribute syntax.
  1278 
  1279 * Discontinued special status of various ML structures that contribute
  1280 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
  1281 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
  1282 refer directly to Ast.Constant, Lexicon.is_identifier,
  1283 Syntax_Trans.mk_binder_tr etc.
  1284 
  1285 * Typed print translation: discontinued show_sorts argument, which is
  1286 already available via context of "advanced" translation.
  1287 
  1288 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
  1289 goal states; body tactic needs to address all subgoals uniformly.
  1290 
  1291 * Slightly more special eq_list/eq_set, with shortcut involving
  1292 pointer equality (assumes that eq relation is reflexive).
  1293 
  1294 * Classical tactics use proper Proof.context instead of historic types
  1295 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  1296 operate directly on Proof.context.  Raw type claset retains its use as
  1297 snapshot of the classical context, which can be recovered via
  1298 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  1299 INCOMPATIBILITY, classical tactics and derived proof methods require
  1300 proper Proof.context.
  1301 
  1302 
  1303 *** System ***
  1304 
  1305 * Discontinued support for Poly/ML 5.2, which was the last version
  1306 without proper multithreading and TimeLimit implementation.
  1307 
  1308 * Discontinued old lib/scripts/polyml-platform, which has been
  1309 obsolete since Isabelle2009-2.
  1310 
  1311 * Various optional external tools are referenced more robustly and
  1312 uniformly by explicit Isabelle settings as follows:
  1313 
  1314   ISABELLE_CSDP   (formerly CSDP_EXE)
  1315   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  1316   ISABELLE_OCAML  (formerly EXEC_OCAML)
  1317   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  1318   ISABELLE_YAP    (formerly EXEC_YAP)
  1319 
  1320 Note that automated detection from the file-system or search path has
  1321 been discontinued.  INCOMPATIBILITY.
  1322 
  1323 * Scala layer provides JVM method invocation service for static
  1324 methods of type (String)String, see Invoke_Scala.method in ML.  For
  1325 example:
  1326 
  1327   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  1328 
  1329 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  1330 this allows to pass structured values between ML and Scala.
  1331 
  1332 * The IsabelleText fonts includes some further glyphs to support the
  1333 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  1334 installed a local copy (which is normally *not* required) need to
  1335 delete or update it from ~~/lib/fonts/.
  1336 
  1337 
  1338 
  1339 New in Isabelle2011 (January 2011)
  1340 ----------------------------------
  1341 
  1342 *** General ***
  1343 
  1344 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  1345 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  1346 useful tooltips and hyperlinks produced from its static analysis.  The
  1347 bundled component provides an executable Isabelle tool that can be run
  1348 like this:
  1349 
  1350   Isabelle2011/bin/isabelle jedit
  1351 
  1352 * Significantly improved Isabelle/Isar implementation manual.
  1353 
  1354 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  1355 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  1356 while the default heap location within that directory lacks that extra
  1357 suffix.  This isolates multiple Isabelle installations from each
  1358 other, avoiding problems with old settings in new versions.
  1359 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  1360 
  1361 * Source files are always encoded as UTF-8, instead of old-fashioned
  1362 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  1363 the following package declarations:
  1364 
  1365   \usepackage[utf8]{inputenc}
  1366   \usepackage{textcomp}
  1367 
  1368 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  1369 a Unicode character is treated as a single symbol, not a sequence of
  1370 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  1371 contain symbols without further backslash escapes, Unicode can now be
  1372 used here as well.  Recall that Symbol.explode in ML provides a
  1373 consistent view on symbols, while raw explode (or String.explode)
  1374 merely give a byte-oriented representation.
  1375 
  1376 * Theory loader: source files are primarily located via the master
  1377 directory of each theory node (where the .thy file itself resides).
  1378 The global load path is still partially available as legacy feature.
  1379 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  1380 explicit paths, relatively to the theory.
  1381 
  1382 * Special treatment of ML file names has been discontinued.
  1383 Historically, optional extensions .ML or .sml were added on demand --
  1384 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  1385 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  1386 
  1387 * Various options that affect pretty printing etc. are now properly
  1388 handled within the context via configuration options, instead of
  1389 unsynchronized references or print modes.  There are both ML Config.T
  1390 entities and Isar declaration attributes to access these.
  1391 
  1392   ML (Config.T)                 Isar (attribute)
  1393 
  1394   eta_contract                  eta_contract
  1395   show_brackets                 show_brackets
  1396   show_sorts                    show_sorts
  1397   show_types                    show_types
  1398   show_question_marks           show_question_marks
  1399   show_consts                   show_consts
  1400   show_abbrevs                  show_abbrevs
  1401 
  1402   Syntax.ast_trace              syntax_ast_trace
  1403   Syntax.ast_stat               syntax_ast_stat
  1404   Syntax.ambiguity_level        syntax_ambiguity_level
  1405 
  1406   Goal_Display.goals_limit      goals_limit
  1407   Goal_Display.show_main_goal   show_main_goal
  1408 
  1409   Method.rule_trace             rule_trace
  1410 
  1411   Thy_Output.display            thy_output_display
  1412   Thy_Output.quotes             thy_output_quotes
  1413   Thy_Output.indent             thy_output_indent
  1414   Thy_Output.source             thy_output_source
  1415   Thy_Output.break              thy_output_break
  1416 
  1417 Note that corresponding "..._default" references in ML may only be
  1418 changed globally at the ROOT session setup, but *not* within a theory.
  1419 The option "show_abbrevs" supersedes the former print mode
  1420 "no_abbrevs" with inverted meaning.
  1421 
  1422 * More systematic naming of some configuration options.
  1423 INCOMPATIBILITY.
  1424 
  1425   trace_simp  ~>  simp_trace
  1426   debug_simp  ~>  simp_debug
  1427 
  1428 * Support for real valued configuration options, using simplistic
  1429 floating-point notation that coincides with the inner syntax for
  1430 float_token.
  1431 
  1432 * Support for real valued preferences (with approximative PGIP type):
  1433 front-ends need to accept "pgint" values in float notation.
  1434 INCOMPATIBILITY.
  1435 
  1436 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  1437 DejaVu Sans.
  1438 
  1439 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  1440 
  1441 
  1442 *** Pure ***
  1443 
  1444 * Command 'type_synonym' (with single argument) replaces somewhat
  1445 outdated 'types', which is still available as legacy feature for some
  1446 time.
  1447 
  1448 * Command 'nonterminal' (with 'and' separated list of arguments)
  1449 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  1450 
  1451 * Command 'notepad' replaces former 'example_proof' for
  1452 experimentation in Isar without any result.  INCOMPATIBILITY.
  1453 
  1454 * Locale interpretation commands 'interpret' and 'sublocale' accept
  1455 lists of equations to map definitions in a locale to appropriate
  1456 entities in the context of the interpretation.  The 'interpretation'
  1457 command already provided this functionality.
  1458 
  1459 * Diagnostic command 'print_dependencies' prints the locale instances
  1460 that would be activated if the specified expression was interpreted in
  1461 the current context.  Variant "print_dependencies!" assumes a context
  1462 without interpretations.
  1463 
  1464 * Diagnostic command 'print_interps' prints interpretations in proofs
  1465 in addition to interpretations in theories.
  1466 
  1467 * Discontinued obsolete 'global' and 'local' commands to manipulate
  1468 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  1469 Sign.root_path and Sign.local_path may be applied directly where this
  1470 feature is still required for historical reasons.
  1471 
  1472 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  1473 'definition' instead.
  1474 
  1475 * The "prems" fact, which refers to the accidental collection of
  1476 foundational premises in the context, is now explicitly marked as
  1477 legacy feature and will be discontinued soon.  Consider using "assms"
  1478 of the head statement or reference facts by explicit names.
  1479 
  1480 * Document antiquotations @{class} and @{type} print classes and type
  1481 constructors.
  1482 
  1483 * Document antiquotation @{file} checks file/directory entries within
  1484 the local file system.
  1485 
  1486 
  1487 *** HOL ***
  1488 
  1489 * Coercive subtyping: functions can be declared as coercions and type
  1490 inference will add them as necessary upon input of a term.  Theory
  1491 Complex_Main declares real :: nat => real and real :: int => real as
  1492 coercions. A coercion function f is declared like this:
  1493 
  1494   declare [[coercion f]]
  1495 
  1496 To lift coercions through type constructors (e.g. from nat => real to
  1497 nat list => real list), map functions can be declared, e.g.
  1498 
  1499   declare [[coercion_map map]]
  1500 
  1501 Currently coercion inference is activated only in theories including
  1502 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1503 the configuration option "coercion_enabled", e.g. it can be enabled in
  1504 other theories like this:
  1505 
  1506   declare [[coercion_enabled]]
  1507 
  1508 * Command 'partial_function' provides basic support for recursive
  1509 function definitions over complete partial orders.  Concrete instances
  1510 are provided for i) the option type, ii) tail recursion on arbitrary
  1511 types, and iii) the heap monad of Imperative_HOL.  See
  1512 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1513 for examples.
  1514 
  1515 * Function package: f.psimps rules are no longer implicitly declared
  1516 as [simp].  INCOMPATIBILITY.
  1517 
  1518 * Datatype package: theorems generated for executable equality (class
  1519 "eq") carry proper names and are treated as default code equations.
  1520 
  1521 * Inductive package: now offers command 'inductive_simps' to
  1522 automatically derive instantiated and simplified equations for
  1523 inductive predicates, similar to 'inductive_cases'.
  1524 
  1525 * Command 'enriched_type' allows to register properties of the
  1526 functorial structure of types.
  1527 
  1528 * Improved infrastructure for term evaluation using code generator
  1529 techniques, in particular static evaluation conversions.
  1530 
  1531 * Code generator: Scala (2.8 or higher) has been added to the target
  1532 languages.
  1533 
  1534 * Code generator: globbing constant expressions "*" and "Theory.*"
  1535 have been replaced by the more idiomatic "_" and "Theory._".
  1536 INCOMPATIBILITY.
  1537 
  1538 * Code generator: export_code without explicit file declaration prints
  1539 to standard output.  INCOMPATIBILITY.
  1540 
  1541 * Code generator: do not print function definitions for case
  1542 combinators any longer.
  1543 
  1544 * Code generator: simplification with rules determined with
  1545 src/Tools/Code/code_simp.ML and method "code_simp".
  1546 
  1547 * Code generator for records: more idiomatic representation of record
  1548 types.  Warning: records are not covered by ancient SML code
  1549 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1550 rep_datatype declaration helps to succeed then:
  1551 
  1552   record 'a foo = ...
  1553   ...
  1554   rep_datatype foo_ext ...
  1555 
  1556 * Records: logical foundation type for records does not carry a
  1557 '_type' suffix any longer (obsolete due to authentic syntax).
  1558 INCOMPATIBILITY.
  1559 
  1560 * Quickcheck now by default uses exhaustive testing instead of random
  1561 testing.  Random testing can be invoked by "quickcheck [random]",
  1562 exhaustive testing by "quickcheck [exhaustive]".
  1563 
  1564 * Quickcheck instantiates polymorphic types with small finite
  1565 datatypes by default. This enables a simple execution mechanism to
  1566 handle quantifiers and function equality over the finite datatypes.
  1567 
  1568 * Quickcheck random generator has been renamed from "code" to
  1569 "random".  INCOMPATIBILITY.
  1570 
  1571 * Quickcheck now has a configurable time limit which is set to 30
  1572 seconds by default. This can be changed by adding [timeout = n] to the
  1573 quickcheck command. The time limit for Auto Quickcheck is still set
  1574 independently.
  1575 
  1576 * Quickcheck in locales considers interpretations of that locale for
  1577 counter example search.
  1578 
  1579 * Sledgehammer:
  1580   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1581     method. See the Sledgehammer manual for details ("isabelle doc
  1582     sledgehammer").
  1583   - Renamed commands:
  1584     sledgehammer atp_info ~> sledgehammer running_provers
  1585     sledgehammer atp_kill ~> sledgehammer kill_provers
  1586     sledgehammer available_atps ~> sledgehammer available_provers
  1587     INCOMPATIBILITY.
  1588   - Renamed options:
  1589     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1590     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1591     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1592     (and "ms" and "min" are no longer supported)
  1593     INCOMPATIBILITY.
  1594 
  1595 * Nitpick:
  1596   - Renamed options:
  1597     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1598     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1599     INCOMPATIBILITY.
  1600   - Added support for partial quotient types.
  1601   - Added local versions of the "Nitpick.register_xxx" functions.
  1602   - Added "whack" option.
  1603   - Allow registration of quotient types as codatatypes.
  1604   - Improved "merge_type_vars" option to merge more types.
  1605   - Removed unsound "fast_descrs" option.
  1606   - Added custom symmetry breaking for datatypes, making it possible to reach
  1607     higher cardinalities.
  1608   - Prevent the expansion of too large definitions.
  1609 
  1610 * Proof methods "metis" and "meson" now have configuration options
  1611 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1612 to diagnose these tools. E.g.
  1613 
  1614     using [[metis_trace = true]]
  1615 
  1616 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1617 manually as command 'solve_direct'.
  1618 
  1619 * The default SMT solver Z3 must be enabled explicitly (due to
  1620 licensing issues) by setting the environment variable
  1621 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1622 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1623 changing the SMT solver is done via the configuration option
  1624 "smt_solver".
  1625 
  1626 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1627 i.e. "remote_cvc3" and "remote_z3".
  1628 
  1629 * Added basic SMT support for datatypes, records, and typedefs using
  1630 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1631 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1632 support for a similar behavior).  Minor INCOMPATIBILITY.
  1633 
  1634 * Changed SMT configuration options:
  1635   - Renamed:
  1636     z3_proofs ~> smt_oracle (with inverted meaning)
  1637     z3_trace_assms ~> smt_trace_used_facts
  1638     INCOMPATIBILITY.
  1639   - Added:
  1640     smt_verbose
  1641     smt_random_seed
  1642     smt_datatypes
  1643     smt_infer_triggers
  1644     smt_monomorph_limit
  1645     cvc3_options
  1646     remote_cvc3_options
  1647     remote_z3_options
  1648     yices_options
  1649 
  1650 * Boogie output files (.b2i files) need to be declared in the theory
  1651 header.
  1652 
  1653 * Simplification procedure "list_to_set_comprehension" rewrites list
  1654 comprehensions applied to List.set to set comprehensions.  Occasional
  1655 INCOMPATIBILITY, may be deactivated like this:
  1656 
  1657   declare [[simproc del: list_to_set_comprehension]]
  1658 
  1659 * Removed old version of primrec package.  INCOMPATIBILITY.
  1660 
  1661 * Removed simplifier congruence rule of "prod_case", as has for long
  1662 been the case with "split".  INCOMPATIBILITY.
  1663 
  1664 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1665 
  1666 * Removed [split_format ... and ... and ...] version of
  1667 [split_format].  Potential INCOMPATIBILITY.
  1668 
  1669 * Predicate "sorted" now defined inductively, with nice induction
  1670 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1671 
  1672 * Constant "contents" renamed to "the_elem", to free the generic name
  1673 contents for other uses.  INCOMPATIBILITY.
  1674 
  1675 * Renamed class eq and constant eq (for code generation) to class
  1676 equal and constant equal, plus renaming of related facts and various
  1677 tuning.  INCOMPATIBILITY.
  1678 
  1679 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1680 
  1681 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1682 INCOMPATIBILITY.
  1683 
  1684 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1685 avoid confusion with finite sets.  INCOMPATIBILITY.
  1686 
  1687 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1688 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1689 for congruent(2)).
  1690 
  1691 * Some previously unqualified names have been qualified:
  1692 
  1693   types
  1694     bool ~> HOL.bool
  1695     nat ~> Nat.nat
  1696 
  1697   constants
  1698     Trueprop ~> HOL.Trueprop
  1699     True ~> HOL.True
  1700     False ~> HOL.False
  1701     op & ~> HOL.conj
  1702     op | ~> HOL.disj
  1703     op --> ~> HOL.implies
  1704     op = ~> HOL.eq
  1705     Not ~> HOL.Not
  1706     The ~> HOL.The
  1707     All ~> HOL.All
  1708     Ex ~> HOL.Ex
  1709     Ex1 ~> HOL.Ex1
  1710     Let ~> HOL.Let
  1711     If ~> HOL.If
  1712     Ball ~> Set.Ball
  1713     Bex ~> Set.Bex
  1714     Suc ~> Nat.Suc
  1715     Pair ~> Product_Type.Pair
  1716     fst ~> Product_Type.fst
  1717     snd ~> Product_Type.snd
  1718     curry ~> Product_Type.curry
  1719     op : ~> Set.member
  1720     Collect ~> Set.Collect
  1721 
  1722 INCOMPATIBILITY.
  1723 
  1724 * More canonical naming convention for some fundamental definitions:
  1725 
  1726     bot_bool_eq ~> bot_bool_def
  1727     top_bool_eq ~> top_bool_def
  1728     inf_bool_eq ~> inf_bool_def
  1729     sup_bool_eq ~> sup_bool_def
  1730     bot_fun_eq  ~> bot_fun_def
  1731     top_fun_eq  ~> top_fun_def
  1732     inf_fun_eq  ~> inf_fun_def
  1733     sup_fun_eq  ~> sup_fun_def
  1734 
  1735 INCOMPATIBILITY.
  1736 
  1737 * More stylized fact names:
  1738 
  1739   expand_fun_eq ~> fun_eq_iff
  1740   expand_set_eq ~> set_eq_iff
  1741   set_ext       ~> set_eqI
  1742   nat_number    ~> eval_nat_numeral
  1743 
  1744 INCOMPATIBILITY.
  1745 
  1746 * Refactoring of code-generation specific operations in theory List:
  1747 
  1748   constants
  1749     null ~> List.null
  1750 
  1751   facts
  1752     mem_iff ~> member_def
  1753     null_empty ~> null_def
  1754 
  1755 INCOMPATIBILITY.  Note that these were not supposed to be used
  1756 regularly unless for striking reasons; their main purpose was code
  1757 generation.
  1758 
  1759 Various operations from the Haskell prelude are used for generating
  1760 Haskell code.
  1761 
  1762 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1763 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1764 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1765 
  1766 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1767 "*" and "+" respectively.  INCOMPATIBILITY.
  1768 
  1769 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1770 "Sum_Type.Plus" instead.
  1771 
  1772 * Constant "split" has been merged with constant "prod_case"; names of
  1773 ML functions, facts etc. involving split have been retained so far,
  1774 though.  INCOMPATIBILITY.
  1775 
  1776 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1777 instead.  INCOMPATIBILITY.
  1778 
  1779 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1780 INCOMPATIBILITY.
  1781 
  1782 * Former theory Library/Enum is now part of the HOL-Main image.
  1783 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1784 referred to by its qualified name.
  1785 
  1786   enum    ~>  Enum.enum
  1787   nlists  ~>  Enum.nlists
  1788   product ~>  Enum.product
  1789 
  1790 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1791 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1792 INCOMPATIBILITY.
  1793 
  1794 * Theory Library/SetsAndFunctions has been split into
  1795 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1796 for instance definitions for functions; various improvements.
  1797 INCOMPATIBILITY.
  1798 
  1799 * Theory Library/Multiset provides stable quicksort implementation of
  1800 sort_key.
  1801 
  1802 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1803 INCOMPATIBILITY.
  1804 
  1805 * Session Multivariate_Analysis: introduced a type class for euclidean
  1806 space.  Most theorems are now stated in terms of euclidean spaces
  1807 instead of finite cartesian products.
  1808 
  1809   types
  1810     real ^ 'n ~>  'a::real_vector
  1811               ~>  'a::euclidean_space
  1812               ~>  'a::ordered_euclidean_space
  1813         (depends on your needs)
  1814 
  1815   constants
  1816      _ $ _        ~> _ $$ _
  1817      \<chi> x. _  ~> \<chi>\<chi> x. _
  1818      CARD('n)     ~> DIM('a)
  1819 
  1820 Also note that the indices are now natural numbers and not from some
  1821 finite type. Finite cartesian products of euclidean spaces, products
  1822 of euclidean spaces the real and complex numbers are instantiated to
  1823 be euclidean_spaces.  INCOMPATIBILITY.
  1824 
  1825 * Session Probability: introduced pextreal as positive extended real
  1826 numbers.  Use pextreal as value for measures.  Introduce the
  1827 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1828 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1829 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1830 
  1831 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1832 INCOMPATIBILITY.
  1833 
  1834 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1835 prove verification conditions generated by the SPARK Ada program
  1836 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1837 
  1838 
  1839 *** HOL-Algebra ***
  1840 
  1841 * Theorems for additive ring operations (locale abelian_monoid and
  1842 descendants) are generated by interpretation from their multiplicative
  1843 counterparts.  Names (in particular theorem names) have the mandatory
  1844 qualifier 'add'.  Previous theorem names are redeclared for
  1845 compatibility.
  1846 
  1847 * Structure "int_ring" is now an abbreviation (previously a
  1848 definition).  This fits more natural with advanced interpretations.
  1849 
  1850 
  1851 *** HOLCF ***
  1852 
  1853 * The domain package now runs in definitional mode by default: The
  1854 former command 'new_domain' is now called 'domain'.  To use the domain
  1855 package in its original axiomatic mode, use 'domain (unsafe)'.
  1856 INCOMPATIBILITY.
  1857 
  1858 * The new class "domain" is now the default sort.  Class "predomain"
  1859 is an unpointed version of "domain". Theories can be updated by
  1860 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1861 
  1862   'a::type ~> 'a::countable
  1863   'a::cpo  ~> 'a::predomain
  1864   'a::pcpo ~> 'a::domain
  1865 
  1866 * The old type class "rep" has been superseded by class "domain".
  1867 Accordingly, users of the definitional package must remove any
  1868 "default_sort rep" declarations.  INCOMPATIBILITY.
  1869 
  1870 * The domain package (definitional mode) now supports unpointed
  1871 predomain argument types, as long as they are marked 'lazy'. (Strict
  1872 arguments must be in class "domain".) For example, the following
  1873 domain definition now works:
  1874 
  1875   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1876 
  1877 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1878 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1879 'a option, and 'a list.  Additionally, it configures fixrec and the
  1880 domain package to work with these types.  For example:
  1881 
  1882   fixrec isInl :: "('a + 'b) u -> tr"
  1883     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1884 
  1885   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1886 
  1887 * The "(permissive)" option of fixrec has been replaced with a
  1888 per-equation "(unchecked)" option. See
  1889 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1890 
  1891 * The "bifinite" class no longer fixes a constant "approx"; the class
  1892 now just asserts that such a function exists.  INCOMPATIBILITY.
  1893 
  1894 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1895 defines an embedding of type 'a defl into udom by default; instances
  1896 of "bifinite" and "domain" classes are available in
  1897 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1898 
  1899 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1900 
  1901 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1902 
  1903 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1904 
  1905 * The function "cprod_map" has been renamed to "prod_map".
  1906 INCOMPATIBILITY.
  1907 
  1908 * The monadic bind operator on each powerdomain has new binder syntax
  1909 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1910 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1911 
  1912 * The infix syntax for binary union on each powerdomain has changed
  1913 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1914 syntax.  INCOMPATIBILITY.
  1915 
  1916 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1917 still supported as an input translation.
  1918 
  1919 * Renamed some theorems (the original names are also still available).
  1920 
  1921   expand_fun_below   ~> fun_below_iff
  1922   below_fun_ext      ~> fun_belowI
  1923   expand_cfun_eq     ~> cfun_eq_iff
  1924   ext_cfun           ~> cfun_eqI
  1925   expand_cfun_below  ~> cfun_below_iff
  1926   below_cfun_ext     ~> cfun_belowI
  1927   cont2cont_Rep_CFun ~> cont2cont_APP
  1928 
  1929 * The Abs and Rep functions for various types have changed names.
  1930 Related theorem names have also changed to match. INCOMPATIBILITY.
  1931 
  1932   Rep_CFun  ~> Rep_cfun
  1933   Abs_CFun  ~> Abs_cfun
  1934   Rep_Sprod ~> Rep_sprod
  1935   Abs_Sprod ~> Abs_sprod
  1936   Rep_Ssum  ~> Rep_ssum
  1937   Abs_Ssum  ~> Abs_ssum
  1938 
  1939 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1940 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1941 
  1942 * Various changes to bisimulation/coinduction with domain package:
  1943 
  1944   - Definitions of "bisim" constants no longer mention definedness.
  1945   - With mutual recursion, "bisim" predicate is now curried.
  1946   - With mutual recursion, each type gets a separate coind theorem.
  1947   - Variable names in bisim_def and coinduct rules have changed.
  1948 
  1949 INCOMPATIBILITY.
  1950 
  1951 * Case combinators generated by the domain package for type "foo" are
  1952 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1953 
  1954 * Several theorems have been renamed to more accurately reflect the
  1955 names of constants and types involved.  INCOMPATIBILITY.
  1956 
  1957   thelub_const    ~> lub_const
  1958   lub_const       ~> is_lub_const
  1959   thelubI         ~> lub_eqI
  1960   is_lub_lub      ~> is_lubD2
  1961   lubI            ~> is_lub_lub
  1962   unique_lub      ~> is_lub_unique
  1963   is_ub_lub       ~> is_lub_rangeD1
  1964   lub_bin_chain   ~> is_lub_bin_chain
  1965   lub_fun         ~> is_lub_fun
  1966   thelub_fun      ~> lub_fun
  1967   thelub_cfun     ~> lub_cfun
  1968   thelub_Pair     ~> lub_Pair
  1969   lub_cprod       ~> is_lub_prod
  1970   thelub_cprod    ~> lub_prod
  1971   minimal_cprod   ~> minimal_prod
  1972   inst_cprod_pcpo ~> inst_prod_pcpo
  1973   UU_I            ~> bottomI
  1974   compact_UU      ~> compact_bottom
  1975   deflation_UU    ~> deflation_bottom
  1976   finite_deflation_UU ~> finite_deflation_bottom
  1977 
  1978 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1979 
  1980   sq_ord_less_eq_trans ~> below_eq_trans
  1981   sq_ord_eq_less_trans ~> eq_below_trans
  1982   refl_less            ~> below_refl
  1983   trans_less           ~> below_trans
  1984   antisym_less         ~> below_antisym
  1985   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1986   box_less             ~> box_below
  1987   rev_trans_less       ~> rev_below_trans
  1988   not_less2not_eq      ~> not_below2not_eq
  1989   less_UU_iff          ~> below_UU_iff
  1990   flat_less_iff        ~> flat_below_iff
  1991   adm_less             ~> adm_below
  1992   adm_not_less         ~> adm_not_below
  1993   adm_compact_not_less ~> adm_compact_not_below
  1994   less_fun_def         ~> below_fun_def
  1995   expand_fun_less      ~> fun_below_iff
  1996   less_fun_ext         ~> fun_belowI
  1997   less_discr_def       ~> below_discr_def
  1998   discr_less_eq        ~> discr_below_eq
  1999   less_unit_def        ~> below_unit_def
  2000   less_cprod_def       ~> below_prod_def
  2001   prod_lessI           ~> prod_belowI
  2002   Pair_less_iff        ~> Pair_below_iff
  2003   fst_less_iff         ~> fst_below_iff
  2004   snd_less_iff         ~> snd_below_iff
  2005   expand_cfun_less     ~> cfun_below_iff
  2006   less_cfun_ext        ~> cfun_belowI
  2007   injection_less       ~> injection_below
  2008   less_up_def          ~> below_up_def
  2009   not_Iup_less         ~> not_Iup_below
  2010   Iup_less             ~> Iup_below
  2011   up_less              ~> up_below
  2012   Def_inject_less_eq   ~> Def_below_Def
  2013   Def_less_is_eq       ~> Def_below_iff
  2014   spair_less_iff       ~> spair_below_iff
  2015   less_sprod           ~> below_sprod
  2016   spair_less           ~> spair_below
  2017   sfst_less_iff        ~> sfst_below_iff
  2018   ssnd_less_iff        ~> ssnd_below_iff
  2019   fix_least_less       ~> fix_least_below
  2020   dist_less_one        ~> dist_below_one
  2021   less_ONE             ~> below_ONE
  2022   ONE_less_iff         ~> ONE_below_iff
  2023   less_sinlD           ~> below_sinlD
  2024   less_sinrD           ~> below_sinrD
  2025 
  2026 
  2027 *** FOL and ZF ***
  2028 
  2029 * All constant names are now qualified internally and use proper
  2030 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  2031 
  2032 
  2033 *** ML ***
  2034 
  2035 * Antiquotation @{assert} inlines a function bool -> unit that raises
  2036 Fail if the argument is false.  Due to inlining the source position of
  2037 failed assertions is included in the error output.
  2038 
  2039 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  2040 text is in practice always evaluated with a stable theory checkpoint.
  2041 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  2042 
  2043 * Antiquotation @{theory A} refers to theory A from the ancestry of
  2044 the current context, not any accidental theory loader state as before.
  2045 Potential INCOMPATIBILITY, subtle change in semantics.
  2046 
  2047 * Syntax.pretty_priority (default 0) configures the required priority
  2048 of pretty-printed output and thus affects insertion of parentheses.
  2049 
  2050 * Syntax.default_root (default "any") configures the inner syntax
  2051 category (nonterminal symbol) for parsing of terms.
  2052 
  2053 * Former exception Library.UnequalLengths now coincides with
  2054 ListPair.UnequalLengths.
  2055 
  2056 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  2057 main functionality is provided by structure Simplifier.
  2058 
  2059 * Renamed raw "explode" function to "raw_explode" to emphasize its
  2060 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  2061 almost all situations.
  2062 
  2063 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  2064 See implementation manual for further details on exceptions in
  2065 Isabelle/ML.
  2066 
  2067 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  2068 meaning.
  2069 
  2070 * Renamed structure PureThy to Pure_Thy and moved most of its
  2071 operations to structure Global_Theory, to emphasize that this is
  2072 rarely-used global-only stuff.
  2073 
  2074 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  2075 instead (or tracing for high-volume output).
  2076 
  2077 * Configuration option show_question_marks only affects regular pretty
  2078 printing of types and terms, not raw Term.string_of_vname.
  2079 
  2080 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  2081 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  2082 @{thms} for most purposes.
  2083 
  2084 * ML structure Unsynchronized is never opened, not even in Isar
  2085 interaction mode as before.  Old Unsynchronized.set etc. have been
  2086 discontinued -- use plain := instead.  This should be *rare* anyway,
  2087 since modern tools always work via official context data, notably
  2088 configuration options.
  2089 
  2090 * Parallel and asynchronous execution requires special care concerning
  2091 interrupts.  Structure Exn provides some convenience functions that
  2092 avoid working directly with raw Interrupt.  User code must not absorb
  2093 interrupts -- intermediate handling (for cleanup etc.) needs to be
  2094 followed by re-raising of the original exception.  Another common
  2095 source of mistakes are "handle _" patterns, which make the meaning of
  2096 the program subject to physical effects of the environment.
  2097 
  2098 
  2099 
  2100 New in Isabelle2009-2 (June 2010)
  2101 ---------------------------------
  2102 
  2103 *** General ***
  2104 
  2105 * Authentic syntax for *all* logical entities (type classes, type
  2106 constructors, term constants): provides simple and robust
  2107 correspondence between formal entities and concrete syntax.  Within
  2108 the parse tree / AST representations, "constants" are decorated by
  2109 their category (class, type, const) and spelled out explicitly with
  2110 their full internal name.
  2111 
  2112 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  2113 and translations (translation rules and translation functions in ML).
  2114 Some hints on upgrading:
  2115 
  2116   - Many existing uses of 'syntax' and 'translations' can be replaced
  2117     by more modern 'type_notation', 'notation' and 'abbreviation',
  2118     which are independent of this issue.
  2119 
  2120   - 'translations' require markup within the AST; the term syntax
  2121     provides the following special forms:
  2122 
  2123       CONST c   -- produces syntax version of constant c from context
  2124       XCONST c  -- literally c, checked as constant from context
  2125       c         -- literally c, if declared by 'syntax'
  2126 
  2127     Plain identifiers are treated as AST variables -- occasionally the
  2128     system indicates accidental variables via the error "rhs contains
  2129     extra variables".
  2130 
  2131     Type classes and type constructors are marked according to their
  2132     concrete syntax.  Some old translations rules need to be written
  2133     for the "type" category, using type constructor application
  2134     instead of pseudo-term application of the default category
  2135     "logic".
  2136 
  2137   - 'parse_translation' etc. in ML may use the following
  2138     antiquotations:
  2139 
  2140       @{class_syntax c}   -- type class c within parse tree / AST
  2141       @{term_syntax c}    -- type constructor c within parse tree / AST
  2142       @{const_syntax c}   -- ML version of "CONST c" above
  2143       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  2144 
  2145   - Literal types within 'typed_print_translations', i.e. those *not*
  2146     represented as pseudo-terms are represented verbatim.  Use @{class
  2147     c} or @{type_name c} here instead of the above syntax
  2148     antiquotations.
  2149 
  2150 Note that old non-authentic syntax was based on unqualified base
  2151 names, so all of the above "constant" names would coincide.  Recall
  2152 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  2153 diagnose syntax problems.
  2154 
  2155 * Type constructors admit general mixfix syntax, not just infix.
  2156 
  2157 * Concrete syntax may be attached to local entities without a proof
  2158 body, too.  This works via regular mixfix annotations for 'fix',
  2159 'def', 'obtain' etc. or via the explicit 'write' command, which is
  2160 similar to the 'notation' command in theory specifications.
  2161 
  2162 * Discontinued unnamed infix syntax (legacy feature for many years) --
  2163 need to specify constant name and syntax separately.  Internal ML
  2164 datatype constructors have been renamed from InfixName to Infix etc.
  2165 Minor INCOMPATIBILITY.
  2166 
  2167 * Schematic theorem statements need to be explicitly markup as such,
  2168 via commands 'schematic_lemma', 'schematic_theorem',
  2169 'schematic_corollary'.  Thus the relevance of the proof is made
  2170 syntactically clear, which impacts performance in a parallel or
  2171 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  2172 
  2173 * Use of cumulative prems via "!" in some proof methods has been
  2174 discontinued (old legacy feature).
  2175 
  2176 * References 'trace_simp' and 'debug_simp' have been replaced by
  2177 configuration options stored in the context. Enabling tracing (the
  2178 case of debugging is similar) in proofs works via
  2179 
  2180   using [[trace_simp = true]]
  2181 
  2182 Tracing is then active for all invocations of the simplifier in
  2183 subsequent goal refinement steps. Tracing may also still be enabled or
  2184 disabled via the ProofGeneral settings menu.
  2185 
  2186 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  2187 'hide_fact' replace the former 'hide' KIND command.  Minor
  2188 INCOMPATIBILITY.
  2189 
  2190 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  2191 more efficient than combinations with -q1 or -q2.
  2192 
  2193 
  2194 *** Pure ***
  2195 
  2196 * Proofterms record type-class reasoning explicitly, using the
  2197 "unconstrain" operation internally.  This eliminates all sort
  2198 constraints from a theorem and proof, introducing explicit
  2199 OFCLASS-premises.  On the proof term level, this operation is
  2200 automatically applied at theorem boundaries, such that closed proofs
  2201 are always free of sort constraints.  INCOMPATIBILITY for tools that
  2202 inspect proof terms.
  2203 
  2204 * Local theory specifications may depend on extra type variables that
  2205 are not present in the result type -- arguments TYPE('a) :: 'a itself
  2206 are added internally.  For example:
  2207 
  2208   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  2209 
  2210 * Predicates of locales introduced by classes carry a mandatory
  2211 "class" prefix.  INCOMPATIBILITY.
  2212 
  2213 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  2214 
  2215 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  2216 'class' instead.
  2217 
  2218 * Command 'code_reflect' allows to incorporate generated ML code into
  2219 runtime environment; replaces immature code_datatype antiquotation.
  2220 INCOMPATIBILITY.
  2221 
  2222 * Code generator: simple concept for abstract datatypes obeying
  2223 invariants.
  2224 
  2225 * Code generator: details of internal data cache have no impact on the
  2226 user space functionality any longer.
  2227 
  2228 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  2229 subgoals.  This is more appropriate for interpretations with 'where'.
  2230 INCOMPATIBILITY.
  2231 
  2232 * Command 'example_proof' opens an empty proof body.  This allows to
  2233 experiment with Isar, without producing any persistent result.
  2234 
  2235 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  2236 within a local theory context, with explicit checking of the
  2237 constructors involved (in contrast to the raw 'syntax' versions).
  2238 
  2239 * Commands 'types' and 'typedecl' now work within a local theory
  2240 context -- without introducing dependencies on parameters or
  2241 assumptions, which is not possible in Isabelle/Pure.
  2242 
  2243 * Command 'defaultsort' has been renamed to 'default_sort', it works
  2244 within a local theory context.  Minor INCOMPATIBILITY.
  2245 
  2246 
  2247 *** HOL ***
  2248 
  2249 * Command 'typedef' now works within a local theory context -- without
  2250 introducing dependencies on parameters or assumptions, which is not
  2251 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  2252 contain multiple interpretations of local typedefs (with different
  2253 non-emptiness proofs), even in a global theory context.
  2254 
  2255 * New package for quotient types.  Commands 'quotient_type' and
  2256 'quotient_definition' may be used for defining types and constants by
  2257 quotient constructions.  An example is the type of integers created by
  2258 quotienting pairs of natural numbers:
  2259 
  2260   fun
  2261     intrel :: "(nat * nat) => (nat * nat) => bool"
  2262   where
  2263     "intrel (x, y) (u, v) = (x + v = u + y)"
  2264 
  2265   quotient_type int = "nat * nat" / intrel
  2266     by (auto simp add: equivp_def expand_fun_eq)
  2267 
  2268   quotient_definition
  2269     "0::int" is "(0::nat, 0::nat)"
  2270 
  2271 The method "lifting" can be used to lift of theorems from the
  2272 underlying "raw" type to the quotient type.  The example
  2273 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  2274 construction and provides a reasoning infrastructure for finite sets.
  2275 
  2276 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  2277 clash with new theory Quotient in Main HOL.
  2278 
  2279 * Moved the SMT binding into the main HOL session, eliminating
  2280 separate HOL-SMT session.
  2281 
  2282 * List membership infix mem operation is only an input abbreviation.
  2283 INCOMPATIBILITY.
  2284 
  2285 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  2286 for future developements; former Library/Word.thy is still present in
  2287 the AFP entry RSAPPS.
  2288 
  2289 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  2290 longer shadowed.  INCOMPATIBILITY.
  2291 
  2292 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  2293 INCOMPATIBILITY.
  2294 
  2295 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  2296 INCOMPATIBILITY.
  2297 
  2298 * Dropped normalizing_semiring etc; use the facts in semiring classes
  2299 instead.  INCOMPATIBILITY.
  2300 
  2301 * Dropped several real-specific versions of lemmas about floor and
  2302 ceiling; use the generic lemmas from theory "Archimedean_Field"
  2303 instead.  INCOMPATIBILITY.
  2304 
  2305   floor_number_of_eq         ~> floor_number_of
  2306   le_floor_eq_number_of      ~> number_of_le_floor
  2307   le_floor_eq_zero           ~> zero_le_floor
  2308   le_floor_eq_one            ~> one_le_floor
  2309   floor_less_eq_number_of    ~> floor_less_number_of
  2310   floor_less_eq_zero         ~> floor_less_zero
  2311   floor_less_eq_one          ~> floor_less_one
  2312   less_floor_eq_number_of    ~> number_of_less_floor
  2313   less_floor_eq_zero         ~> zero_less_floor
  2314   less_floor_eq_one          ~> one_less_floor
  2315   floor_le_eq_number_of      ~> floor_le_number_of
  2316   floor_le_eq_zero           ~> floor_le_zero
  2317   floor_le_eq_one            ~> floor_le_one
  2318   floor_subtract_number_of   ~> floor_diff_number_of
  2319   floor_subtract_one         ~> floor_diff_one
  2320   ceiling_number_of_eq       ~> ceiling_number_of
  2321   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  2322   ceiling_le_zero_eq         ~> ceiling_le_zero
  2323   ceiling_le_eq_one          ~> ceiling_le_one
  2324   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  2325   less_ceiling_eq_zero       ~> zero_less_ceiling
  2326   less_ceiling_eq_one        ~> one_less_ceiling
  2327   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  2328   ceiling_less_eq_zero       ~> ceiling_less_zero
  2329   ceiling_less_eq_one        ~> ceiling_less_one
  2330   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  2331   le_ceiling_eq_zero         ~> zero_le_ceiling
  2332   le_ceiling_eq_one          ~> one_le_ceiling
  2333   ceiling_subtract_number_of ~> ceiling_diff_number_of
  2334   ceiling_subtract_one       ~> ceiling_diff_one
  2335 
  2336 * Theory "Finite_Set": various folding_XXX locales facilitate the
  2337 application of the various fold combinators on finite sets.
  2338 
  2339 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  2340 provides abstract red-black tree type which is backed by "RBT_Impl" as
  2341 implementation.  INCOMPATIBILTY.
  2342 
  2343 * Theory Library/Coinductive_List has been removed -- superseded by
  2344 AFP/thys/Coinductive.
  2345 
  2346 * Theory PReal, including the type "preal" and related operations, has
  2347 been removed.  INCOMPATIBILITY.
  2348 
  2349 * Real: new development using Cauchy Sequences.
  2350 
  2351 * Split off theory "Big_Operators" containing setsum, setprod,
  2352 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  2353 
  2354 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  2355 "Int" etc.  INCOMPATIBILITY.
  2356 
  2357 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  2358 
  2359 * New set of rules "ac_simps" provides combined assoc / commute
  2360 rewrites for all interpretations of the appropriate generic locales.
  2361 
  2362 * Renamed theory "OrderedGroup" to "Groups" and split theory
  2363 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  2364 appropriate and more consistent names suitable for name prefixes
  2365 within the HOL theories.  INCOMPATIBILITY.
  2366 
  2367 * Some generic constants have been put to appropriate theories:
  2368   - less_eq, less: Orderings
  2369   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  2370   - inverse, divide: Rings
  2371 INCOMPATIBILITY.
  2372 
  2373 * More consistent naming of type classes involving orderings (and
  2374 lattices):
  2375 
  2376     lower_semilattice                   ~> semilattice_inf
  2377     upper_semilattice                   ~> semilattice_sup
  2378 
  2379     dense_linear_order                  ~> dense_linorder
  2380 
  2381     pordered_ab_group_add               ~> ordered_ab_group_add
  2382     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  2383     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  2384     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  2385     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  2386     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  2387     pordered_cancel_semiring            ~> ordered_cancel_semiring
  2388     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  2389     pordered_comm_ring                  ~> ordered_comm_ring
  2390     pordered_comm_semiring              ~> ordered_comm_semiring
  2391     pordered_ring                       ~> ordered_ring
  2392     pordered_ring_abs                   ~> ordered_ring_abs
  2393     pordered_semiring                   ~> ordered_semiring
  2394 
  2395     ordered_ab_group_add                ~> linordered_ab_group_add
  2396     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  2397     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  2398     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  2399     ordered_field                       ~> linordered_field
  2400     ordered_field_no_lb                 ~> linordered_field_no_lb
  2401     ordered_field_no_ub                 ~> linordered_field_no_ub
  2402     ordered_field_dense_linear_order    ~> dense_linordered_field
  2403     ordered_idom                        ~> linordered_idom
  2404     ordered_ring                        ~> linordered_ring
  2405     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  2406     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  2407     ordered_ring_strict                 ~> linordered_ring_strict
  2408     ordered_semidom                     ~> linordered_semidom
  2409     ordered_semiring                    ~> linordered_semiring
  2410     ordered_semiring_1                  ~> linordered_semiring_1
  2411     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  2412     ordered_semiring_strict             ~> linordered_semiring_strict
  2413 
  2414   The following slightly odd type classes have been moved to a
  2415   separate theory Library/Lattice_Algebras:
  2416 
  2417     lordered_ab_group_add               ~> lattice_ab_group_add
  2418     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  2419     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  2420     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  2421     lordered_ring                       ~> lattice_ring
  2422 
  2423 INCOMPATIBILITY.
  2424 
  2425 * Refined field classes:
  2426   - classes division_ring_inverse_zero, field_inverse_zero,
  2427     linordered_field_inverse_zero include rule inverse 0 = 0 --
  2428     subsumes former division_by_zero class;
  2429   - numerous lemmas have been ported from field to division_ring.
  2430 INCOMPATIBILITY.
  2431 
  2432 * Refined algebra theorem collections:
  2433   - dropped theorem group group_simps, use algebra_simps instead;
  2434   - dropped theorem group ring_simps, use field_simps instead;
  2435   - proper theorem collection field_simps subsumes former theorem
  2436     groups field_eq_simps and field_simps;
  2437   - dropped lemma eq_minus_self_iff which is a duplicate for
  2438     equal_neg_zero.
  2439 INCOMPATIBILITY.
  2440 
  2441 * Theory Finite_Set and List: some lemmas have been generalized from
  2442 sets to lattices:
  2443 
  2444   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  2445   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  2446   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  2447   union_Union_fold_union        ~> sup_Sup_fold_sup
  2448   Inter_fold_inter              ~> Inf_fold_inf
  2449   Union_fold_union              ~> Sup_fold_sup
  2450   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  2451   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  2452   INTER_fold_inter              ~> INFI_fold_inf
  2453   UNION_fold_union              ~> SUPR_fold_sup
  2454 
  2455 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  2456 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  2457 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  2458 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  2459 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  2460 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  2461 
  2462 * Reorganized theory Multiset: swapped notation of pointwise and
  2463 multiset order:
  2464 
  2465   - pointwise ordering is instance of class order with standard syntax
  2466     <= and <;
  2467   - multiset ordering has syntax <=# and <#; partial order properties
  2468     are provided by means of interpretation with prefix
  2469     multiset_order;
  2470   - less duplication, less historical organization of sections,
  2471     conversion from associations lists to multisets, rudimentary code
  2472     generation;
  2473   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  2474     if needed.
  2475 
  2476 Renamed:
  2477 
  2478   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  2479   multi_count_ext  ~>  multiset_ext
  2480   diff_union_inverse2  ~>  diff_union_cancelR
  2481 
  2482 INCOMPATIBILITY.
  2483 
  2484 * Theory Permutation: replaced local "remove" by List.remove1.
  2485 
  2486 * Code generation: ML and OCaml code is decorated with signatures.
  2487 
  2488 * Theory List: added transpose.
  2489 
  2490 * Library/Nat_Bijection.thy is a collection of bijective functions
  2491 between nat and other types, which supersedes the older libraries
  2492 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2493 
  2494   Constants:
  2495   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2496   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2497   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2498   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2499   Countable.pair_encode           ~> prod_encode
  2500   NatIso.prod2nat                 ~> prod_encode
  2501   NatIso.nat2prod                 ~> prod_decode
  2502   NatIso.sum2nat                  ~> sum_encode
  2503   NatIso.nat2sum                  ~> sum_decode
  2504   NatIso.list2nat                 ~> list_encode
  2505   NatIso.nat2list                 ~> list_decode
  2506   NatIso.set2nat                  ~> set_encode
  2507   NatIso.nat2set                  ~> set_decode
  2508 
  2509   Lemmas:
  2510   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2511   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2512   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2513   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2514   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2515   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2516   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2517   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2518   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2519   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2520   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2521   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2522   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2523 
  2524 * Sledgehammer:
  2525   - Renamed ATP commands:
  2526     atp_info     ~> sledgehammer running_atps
  2527     atp_kill     ~> sledgehammer kill_atps
  2528     atp_messages ~> sledgehammer messages
  2529     atp_minimize ~> sledgehammer minimize
  2530     print_atps   ~> sledgehammer available_atps
  2531     INCOMPATIBILITY.
  2532   - Added user's manual ("isabelle doc sledgehammer").
  2533   - Added option syntax and "sledgehammer_params" to customize
  2534     Sledgehammer's behavior.  See the manual for details.
  2535   - Modified the Isar proof reconstruction code so that it produces
  2536     direct proofs rather than proofs by contradiction.  (This feature
  2537     is still experimental.)
  2538   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2539     full-typed mode.
  2540   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2541 
  2542 * Nitpick:
  2543   - Added and implemented "binary_ints" and "bits" options.
  2544   - Added "std" option and implemented support for nonstandard models.
  2545   - Added and implemented "finitize" option to improve the precision
  2546     of infinite datatypes based on a monotonicity analysis.
  2547   - Added support for quotient types.
  2548   - Added support for "specification" and "ax_specification"
  2549     constructs.
  2550   - Added support for local definitions (for "function" and
  2551     "termination" proofs).
  2552   - Added support for term postprocessors.
  2553   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2554   - Improved efficiency of "destroy_constrs" optimization.
  2555   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2556     record getters.
  2557   - Fixed soundness bug related to higher-order constructors.
  2558   - Fixed soundness bug when "full_descrs" is enabled.
  2559   - Improved precision of set constructs.
  2560   - Added "atoms" option.
  2561   - Added cache to speed up repeated Kodkod invocations on the same
  2562     problems.
  2563   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2564     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2565     "SAT4J_Light".  INCOMPATIBILITY.
  2566   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2567     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2568   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2569 
  2570 * Method "induct" now takes instantiations of the form t, where t is not
  2571   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2572   If this is not intended, t has to be enclosed in parentheses.
  2573   By default, the equalities generated by definitional instantiations
  2574   are pre-simplified, which may cause parameters of inductive cases
  2575   to disappear, or may even delete some of the inductive cases.
  2576   Use "induct (no_simp)" instead of "induct" to restore the old
  2577   behaviour. The (no_simp) option is also understood by the "cases"
  2578   and "nominal_induct" methods, which now perform pre-simplification, too.
  2579   INCOMPATIBILITY.
  2580 
  2581 
  2582 *** HOLCF ***
  2583 
  2584 * Variable names in lemmas generated by the domain package have
  2585 changed; the naming scheme is now consistent with the HOL datatype
  2586 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2587 
  2588 * The domain package no longer defines the function "foo_copy" for
  2589 recursive domain "foo".  The reach lemma is now stated directly in
  2590 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2591 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2592 
  2593 * Most definedness lemmas generated by the domain package (previously
  2594 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2595 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2596 Proofs that used definedness lemmas as intro rules may break,
  2597 potential INCOMPATIBILITY.
  2598 
  2599 * Induction and casedist rules generated by the domain package now
  2600 declare proper case_names (one called "bottom", and one named for each
  2601 constructor).  INCOMPATIBILITY.
  2602 
  2603 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2604 rules are generated for each domain, INCOMPATIBILITY.
  2605 
  2606   foo_bar.reach       ~> foo.reach  bar.reach
  2607   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2608 
  2609 * Some lemmas generated by the domain package have been renamed for
  2610 consistency with the datatype package, INCOMPATIBILITY.
  2611 
  2612   foo.ind        ~> foo.induct
  2613   foo.finite_ind ~> foo.finite_induct
  2614   foo.coind      ~> foo.coinduct
  2615   foo.casedist   ~> foo.exhaust
  2616   foo.exhaust    ~> foo.nchotomy
  2617 
  2618 * For consistency with other definition packages, the fixrec package
  2619 now generates qualified theorem names, INCOMPATIBILITY.
  2620 
  2621   foo_simps  ~> foo.simps
  2622   foo_unfold ~> foo.unfold
  2623   foo_induct ~> foo.induct
  2624 
  2625 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2626 method and internal fixrec proofs now use the default simpset instead.
  2627 INCOMPATIBILITY.
  2628 
  2629 * The "contlub" predicate has been removed.  Proof scripts should use
  2630 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2631 
  2632 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2633 
  2634 * The constants cpair, cfst, and csnd have been removed in favor of
  2635 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2636 
  2637 
  2638 *** ML ***
  2639 
  2640 * Antiquotations for basic formal entities:
  2641 
  2642     @{class NAME}         -- type class
  2643     @{class_syntax NAME}  -- syntax representation of the above
  2644 
  2645     @{type_name NAME}     -- logical type
  2646     @{type_abbrev NAME}   -- type abbreviation
  2647     @{nonterminal NAME}   -- type of concrete syntactic category
  2648     @{type_syntax NAME}   -- syntax representation of any of the above
  2649 
  2650     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2651     @{const_abbrev NAME}  -- abbreviated constant
  2652     @{const_syntax NAME}  -- syntax representation of any of the above
  2653 
  2654 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2655 syntax constant (cf. 'syntax' command).
  2656 
  2657 * Antiquotation @{make_string} inlines a function to print arbitrary
  2658 values similar to the ML toplevel.  The result is compiler dependent
  2659 and may fall back on "?" in certain situations.
  2660 
  2661 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2662 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2663 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2664 not work with the asynchronous Isar document model.
  2665 
  2666 * Configuration options now admit dynamic default values, depending on
  2667 the context or even global references.
  2668 
  2669 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2670 uses an efficient external library if available (for Poly/ML).
  2671 
  2672 * Renamed some important ML structures, while keeping the old names
  2673 for some time as aliases within the structure Legacy:
  2674 
  2675   OuterKeyword  ~>  Keyword
  2676   OuterLex      ~>  Token
  2677   OuterParse    ~>  Parse
  2678   OuterSyntax   ~>  Outer_Syntax
  2679   PrintMode     ~>  Print_Mode
  2680   SpecParse     ~>  Parse_Spec
  2681   ThyInfo       ~>  Thy_Info
  2682   ThyLoad       ~>  Thy_Load
  2683   ThyOutput     ~>  Thy_Output
  2684   TypeInfer     ~>  Type_Infer
  2685 
  2686 Note that "open Legacy" simplifies porting of sources, but forgetting
  2687 to remove it again will complicate porting again in the future.
  2688 
  2689 * Most operations that refer to a global context are named
  2690 accordingly, e.g. Simplifier.global_context or
  2691 ProofContext.init_global.  There are some situations where a global
  2692 context actually works, but under normal circumstances one needs to
  2693 pass the proper local context through the code!
  2694 
  2695 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2696 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2697 Pretty.pp argument to merge, which is absent in the standard
  2698 Theory_Data version.
  2699 
  2700 * Sorts.certify_sort and derived "cert" operations for types and terms
  2701 no longer minimize sorts.  Thus certification at the boundary of the
  2702 inference kernel becomes invariant under addition of class relations,
  2703 which is an important monotonicity principle.  Sorts are now minimized
  2704 in the syntax layer only, at the boundary between the end-user and the
  2705 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2706 explicitly in rare situations.
  2707 
  2708 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2709 emphasize that this is in no way a standard operation.
  2710 INCOMPATIBILITY.
  2711 
  2712 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2713 usual for resolution.  Rare INCOMPATIBILITY.
  2714 
  2715 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2716 to emphasize that these only work in a global situation (which is
  2717 quite rare).
  2718 
  2719 * Curried take and drop in library.ML; negative length is interpreted
  2720 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2721 
  2722 * Proof terms: type substitutions on proof constants now use canonical
  2723 order of type variables.  INCOMPATIBILITY for tools working with proof
  2724 terms.
  2725 
  2726 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2727 may no longer carry premises.  User-level specifications are
  2728 transformed accordingly by Thm.add_axiom/add_def.
  2729 
  2730 
  2731 *** System ***
  2732 
  2733 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2734 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2735 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2736 
  2737 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2738 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2739 respectively.
  2740 
  2741 * Old lib/scripts/polyml-platform is superseded by the
  2742 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2743 variant, even on a 64 bit machine.  The following example setting
  2744 prefers 64 bit if available:
  2745 
  2746   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2747 
  2748 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2749 Isabelle/Scala layer for advanced prover interaction and integration.
  2750 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2751 component.
  2752 
  2753 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2754 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2755 similar to the default assignment of the document preparation system
  2756 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2757 provides some operations for direct access to the font without asking
  2758 the user for manual installation.
  2759 
  2760 
  2761 
  2762 New in Isabelle2009-1 (December 2009)
  2763 -------------------------------------
  2764 
  2765 *** General ***
  2766 
  2767 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2768 one backslash should be used, even in ML sources.
  2769 
  2770 
  2771 *** Pure ***
  2772 
  2773 * Locale interpretation propagates mixins along the locale hierarchy.
  2774 The currently only available mixins are the equations used to map
  2775 local definitions to terms of the target domain of an interpretation.
  2776 
  2777 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2778 loc" to print all interpretations of locale "loc" in the theory.
  2779 Interpretations in proofs are not shown.
  2780 
  2781 * Thoroughly revised locales tutorial.  New section on conditional
  2782 interpretation.
  2783 
  2784 * On instantiation of classes, remaining undefined class parameters
  2785 are formally declared.  INCOMPATIBILITY.
  2786 
  2787 
  2788 *** Document preparation ***
  2789 
  2790 * New generalized style concept for printing terms: @{foo (style) ...}
  2791 instead of @{foo_style style ...}  (old form is still retained for
  2792 backward compatibility).  Styles can be also applied for
  2793 antiquotations prop, term_type and typeof.
  2794 
  2795 
  2796 *** HOL ***
  2797 
  2798 * New proof method "smt" for a combination of first-order logic with
  2799 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2800 fixed-size bitvectors; there is also basic support for higher-order
  2801 features (esp. lambda abstractions).  It is an incomplete decision
  2802 procedure based on external SMT solvers using the oracle mechanism;
  2803 for the SMT solver Z3, this method is proof-producing.  Certificates
  2804 are provided to avoid calling the external solvers solely for
  2805 re-checking proofs.  Due to a remote SMT service there is no need for
  2806 installing SMT solvers locally.  See src/HOL/SMT.
  2807 
  2808 * New commands to load and prove verification conditions generated by
  2809 the Boogie program verifier or derived systems (e.g. the Verifying C
  2810 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2811 
  2812 * New counterexample generator tool 'nitpick' based on the Kodkod
  2813 relational model finder.  See src/HOL/Tools/Nitpick and
  2814 src/HOL/Nitpick_Examples.
  2815 
  2816 * New commands 'code_pred' and 'values' to invoke the predicate
  2817 compiler and to enumerate values of inductive predicates.
  2818 
  2819 * A tabled implementation of the reflexive transitive closure.
  2820 
  2821 * New implementation of quickcheck uses generic code generator;
  2822 default generators are provided for all suitable HOL types, records
  2823 and datatypes.  Old quickcheck can be re-activated importing theory
  2824 Library/SML_Quickcheck.
  2825 
  2826 * New testing tool Mirabelle for automated proof tools.  Applies
  2827 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2828 every proof step in a theory.  To be used in batch mode via the
  2829 "mirabelle" utility.
  2830 
  2831 * New proof method "sos" (sum of squares) for nonlinear real
  2832 arithmetic (originally due to John Harison). It requires theory
  2833 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2834 works well in practice on quantifier-free real arithmetic with +, -,
  2835 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2836 inequalities between polynomials.  It makes use of external
  2837 semidefinite programming solvers.  Method "sos" generates a
  2838 certificate that can be pasted into the proof thus avoiding the need
  2839 to call an external tool every time the proof is checked.  See
  2840 src/HOL/Library/Sum_Of_Squares.
  2841 
  2842 * New method "linarith" invokes existing linear arithmetic decision
  2843 procedure only.
  2844 
  2845 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2846 
  2847 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2848 Causes full type information to be output to the ATPs.  This slows
  2849 ATPs down considerably but eliminates a source of unsound "proofs"
  2850 that fail later.
  2851 
  2852 * New method "metisFT": A version of metis that uses full type
  2853 information in order to avoid failures of proof reconstruction.
  2854 
  2855 * New evaluator "approximate" approximates an real valued term using
  2856 the same method as the approximation method.
  2857 
  2858 * Method "approximate" now supports arithmetic expressions as
  2859 boundaries of intervals and implements interval splitting and Taylor
  2860 series expansion.
  2861 
  2862 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2863 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2864 
  2865 * New theory SupInf of the supremum and infimum operators for sets of
  2866 reals.
  2867 
  2868 * New theory Probability, which contains a development of measure
  2869 theory, eventually leading to Lebesgue integration and probability.
  2870 
  2871 * Extended Multivariate Analysis to include derivation and Brouwer's
  2872 fixpoint theorem.
  2873 
  2874 * Reorganization of number theory, INCOMPATIBILITY:
  2875   - new number theory development for nat and int, in theories Divides
  2876     and GCD as well as in new session Number_Theory
  2877   - some constants and facts now suffixed with _nat and _int
  2878     accordingly
  2879   - former session NumberTheory now named Old_Number_Theory, including
  2880     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2881   - moved theory Pocklington from src/HOL/Library to
  2882     src/HOL/Old_Number_Theory
  2883 
  2884 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2885 lcm of finite and infinite sets. It is shown that they form a complete
  2886 lattice.
  2887 
  2888 * Class semiring_div requires superclass no_zero_divisors and proof of
  2889 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2890 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2891 generalized to class semiring_div, subsuming former theorems
  2892 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2893 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2894 INCOMPATIBILITY.
  2895 
  2896 * Refinements to lattice classes and sets:
  2897   - less default intro/elim rules in locale variant, more default
  2898     intro/elim rules in class variant: more uniformity
  2899   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2900     le_inf_iff
  2901   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2902     sup_aci)
  2903   - renamed ACI to inf_sup_aci
  2904   - new class "boolean_algebra"
  2905   - class "complete_lattice" moved to separate theory
  2906     "Complete_Lattice"; corresponding constants (and abbreviations)
  2907     renamed and with authentic syntax:
  2908     Set.Inf ~>    Complete_Lattice.Inf
  2909     Set.Sup ~>    Complete_Lattice.Sup
  2910     Set.INFI ~>   Complete_Lattice.INFI
  2911     Set.SUPR ~>   Complete_Lattice.SUPR
  2912     Set.Inter ~>  Complete_Lattice.Inter
  2913     Set.Union ~>  Complete_Lattice.Union
  2914     Set.INTER ~>  Complete_Lattice.INTER
  2915     Set.UNION ~>  Complete_Lattice.UNION
  2916   - authentic syntax for
  2917     Set.Pow
  2918     Set.image
  2919   - mere abbreviations:
  2920     Set.empty               (for bot)
  2921     Set.UNIV                (for top)
  2922     Set.inter               (for inf, formerly Set.Int)
  2923     Set.union               (for sup, formerly Set.Un)
  2924     Complete_Lattice.Inter  (for Inf)
  2925     Complete_Lattice.Union  (for Sup)
  2926     Complete_Lattice.INTER  (for INFI)
  2927     Complete_Lattice.UNION  (for SUPR)
  2928   - object-logic definitions as far as appropriate
  2929 
  2930 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2931 Un_subset_iff are explicitly deleted as default simp rules; then also
  2932 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2933 deleted to achieve the desired effect.
  2934 
  2935 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2936 rules by default any longer; the same applies to min_max.inf_absorb1
  2937 etc.  INCOMPATIBILITY.
  2938 
  2939 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2940 pred_set_conv by default.  INCOMPATIBILITY.
  2941 
  2942 * Power operations on relations and functions are now one dedicated
  2943 constant "compow" with infix syntax "^^".  Power operation on
  2944 multiplicative monoids retains syntax "^" and is now defined generic
  2945 in class power.  INCOMPATIBILITY.
  2946 
  2947 * Relation composition "R O S" now has a more standard argument order:
  2948 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2949 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2950 break, since the O_assoc rule was not rewritten like this.  Fix using
  2951 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2952 
  2953 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2954 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2955 INCOMPATIBILITY.
  2956 
  2957 * Most rules produced by inductive and datatype package have mandatory
  2958 prefixes.  INCOMPATIBILITY.
  2959 
  2960 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2961 the attribute of the same name.  Each of the theorems in the list
  2962 DERIV_intros assumes composition with an additional function and
  2963 matches a variable to the derivative, which has to be solved by the
  2964 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2965 of most elementary terms.  Former Maclauren.DERIV_tac and
  2966 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2967 INCOMPATIBILITY.
  2968 
  2969 * Code generator attributes follow the usual underscore convention:
  2970     code_unfold     replaces    code unfold
  2971     code_post       replaces    code post
  2972     etc.
  2973   INCOMPATIBILITY.
  2974 
  2975 * Renamed methods:
  2976     sizechange -> size_change
  2977     induct_scheme -> induction_schema
  2978   INCOMPATIBILITY.
  2979 
  2980 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2981 INCOMPATIBILITY, use "undefined" directly.
  2982 
  2983 * Renamed theorems:
  2984     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2985     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2986     Suc_plus1 -> Suc_eq_plus1
  2987     *anti_sym -> *antisym*
  2988     vector_less_eq_def -> vector_le_def
  2989   INCOMPATIBILITY.
  2990 
  2991 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2992 INCOMPATIBILITY.
  2993 
  2994 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2995 INCOMPATIBILITY.
  2996 
  2997 
  2998 *** HOLCF ***
  2999 
  3000 * Theory Representable defines a class "rep" of domains that are
  3001 representable (via an ep-pair) in the universal domain type "udom".
  3002 Instances are provided for all type constructors defined in HOLCF.
  3003 
  3004 * The 'new_domain' command is a purely definitional version of the
  3005 domain package, for representable domains.  Syntax is identical to the
  3006 old domain package.  The 'new_domain' package also supports indirect
  3007 recursion using previously-defined type constructors.  See
  3008 src/HOLCF/ex/New_Domain.thy for examples.
  3009 
  3010 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  3011 on the left-hand side of an equation, and then performs
  3012 simplification.  Rewriting is done using rules declared with the
  3013 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  3014 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  3015 
  3016 * The pattern-match compiler in 'fixrec' can now handle constructors
  3017 with HOL function types.  Pattern-match combinators for the Pair
  3018 constructor are pre-configured.
  3019 
  3020 * The 'fixrec' package now produces better fixed-point induction rules
  3021 for mutually-recursive definitions:  Induction rules have conclusions
  3022 of the form "P foo bar" instead of "P <foo, bar>".
  3023 
  3024 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  3025 been renamed to "below".  The name "below" now replaces "less" in many
  3026 theorem names.  (Legacy theorem names using "less" are still supported
  3027 as well.)
  3028 
  3029 * The 'fixrec' package now supports "bottom patterns".  Bottom
  3030 patterns can be used to generate strictness rules, or to make
  3031 functions more strict (much like the bang-patterns supported by the
  3032 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  3033 examples.
  3034 
  3035 
  3036 *** ML ***
  3037 
  3038 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  3039 errors and run-time exceptions, including detailed source positions.
  3040 
  3041 * Structure Name_Space (formerly NameSpace) now manages uniquely
  3042 identified entries, with some additional information such as source
  3043 position, logical grouping etc.
  3044 
  3045 * Theory and context data is now introduced by the simplified and
  3046 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  3047 to be pure, but the old TheoryDataFun for mutable data (with explicit
  3048 copy operation) is still available for some time.
  3049 
  3050 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  3051 provides a high-level programming interface to synchronized state
  3052 variables with atomic update.  This works via pure function
  3053 application within a critical section -- its runtime should be as
  3054 short as possible; beware of deadlocks if critical code is nested,
  3055 either directly or indirectly via other synchronized variables!
  3056 
  3057 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  3058 wraps raw ML references, explicitly indicating their non-thread-safe
  3059 behaviour.  The Isar toplevel keeps this structure open, to
  3060 accommodate Proof General as well as quick and dirty interactive
  3061 experiments with references.
  3062 
  3063 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  3064 parallel tactical reasoning.
  3065 
  3066 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  3067 are similar to SUBPROOF, but are slightly more flexible: only the
  3068 specified parts of the subgoal are imported into the context, and the
  3069 body tactic may introduce new subgoals and schematic variables.
  3070 
  3071 * Old tactical METAHYPS, which does not observe the proof context, has
  3072 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  3073 or Subgoal.FOCUS etc.
  3074 
  3075 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  3076 functors have their own ML name space there is no point to mark them
  3077 separately.)  Minor INCOMPATIBILITY.
  3078 
  3079 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  3080 
  3081 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  3082 INCOMPATIBILITY.
  3083 
  3084 * Operations of structure Skip_Proof no longer require quick_and_dirty
  3085 mode, which avoids critical setmp.
  3086 
  3087 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  3088 combinators for "args".  INCOMPATIBILITY, need to use simplified
  3089 Attrib/Method.setup introduced in Isabelle2009.
  3090 
  3091 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  3092 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  3093 last resort.  INCOMPATIBILITY.
  3094 
  3095 * Display.pretty_thm now requires a proper context (cf. former
  3096 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  3097 or even Display.pretty_thm_without_context as last resort.
  3098 INCOMPATIBILITY.
  3099 
  3100 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  3101 Syntax.pretty_typ/term directly, preferably with proper context
  3102 instead of global theory.
  3103 
  3104 
  3105 *** System ***
  3106 
  3107 * Further fine tuning of parallel proof checking, scales up to 8 cores
  3108 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  3109 usedir option -q.
  3110 
  3111 * Support for additional "Isabelle components" via etc/components, see
  3112 also the system manual.
  3113 
  3114 * The isabelle makeall tool now operates on all components with
  3115 IsaMakefile, not just hardwired "logics".
  3116 
  3117 * Removed "compress" option from isabelle-process and isabelle usedir;
  3118 this is always enabled.
  3119 
  3120 * Discontinued support for Poly/ML 4.x versions.
  3121 
  3122 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  3123 on a given logic image.  This requires the lighttpd webserver and is
  3124 currently supported on Linux only.
  3125 
  3126 
  3127 
  3128 New in Isabelle2009 (April 2009)
  3129 --------------------------------
  3130 
  3131 *** General ***
  3132 
  3133 * Simplified main Isabelle executables, with less surprises on
  3134 case-insensitive file-systems (such as Mac OS).
  3135 
  3136   - The main Isabelle tool wrapper is now called "isabelle" instead of
  3137     "isatool."
  3138 
  3139   - The former "isabelle" alias for "isabelle-process" has been
  3140     removed (should rarely occur to regular users).
  3141 
  3142   - The former "isabelle-interface" and its alias "Isabelle" have been
  3143     removed (interfaces are now regular Isabelle tools).
  3144 
  3145 Within scripts and make files, the Isabelle environment variables
  3146 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  3147 respectively.  (The latter are still available as legacy feature.)
  3148 
  3149 The old isabelle-interface wrapper could react in confusing ways if
  3150 the interface was uninstalled or changed otherwise.  Individual
  3151 interface tool configuration is now more explicit, see also the
  3152 Isabelle system manual.  In particular, Proof General is now available
  3153 via "isabelle emacs".
  3154 
  3155 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  3156 purge installed copies of Isabelle executables and re-run "isabelle
  3157 install -p ...", or use symlinks.
  3158 
  3159 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  3160 old ~/isabelle, which was slightly non-standard and apt to cause
  3161 surprises on case-insensitive file-systems (such as Mac OS).
  3162 
  3163 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  3164 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  3165 care is required when using older releases of Isabelle.  Note that
  3166 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  3167 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  3168 
  3169 * Proofs of fully specified statements are run in parallel on
  3170 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  3171 a regular 4-core machine, if the initial heap space is made reasonably
  3172 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  3173 
  3174 * The main reference manuals ("isar-ref", "implementation", and
  3175 "system") have been updated and extended.  Formally checked references
  3176 as hyperlinks are now available uniformly.
  3177 
  3178 
  3179 *** Pure ***
  3180 
  3181 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  3182 respects.  The most important changes are listed below.  See the
  3183 Tutorial on Locales ("locales" manual) for details.
  3184 
  3185 - In locale expressions, instantiation replaces renaming.  Parameters
  3186 must be declared in a for clause.  To aid compatibility with previous
  3187 parameter inheritance, in locale declarations, parameters that are not
  3188 'touched' (instantiation position "_" or omitted) are implicitly added
  3189 with their syntax at the beginning of the for clause.
  3190 
  3191 - Syntax from abbreviations and definitions in locales is available in
  3192 locale expressions and context elements.  The latter is particularly
  3193 useful in locale declarations.
  3194 
  3195 - More flexible mechanisms to qualify names generated by locale
  3196 expressions.  Qualifiers (prefixes) may be specified in locale
  3197 expressions, and can be marked as mandatory (syntax: "name!:") or
  3198 optional (syntax "name?:").  The default depends for plain "name:"
  3199 depends on the situation where a locale expression is used: in
  3200 commands 'locale' and 'sublocale' prefixes are optional, in
  3201 'interpretation' and 'interpret' prefixes are mandatory.  The old
  3202 implicit qualifiers derived from the parameter names of a locale are
  3203 no longer generated.
  3204 
  3205 - Command "sublocale l < e" replaces "interpretation l < e".  The
  3206 instantiation clause in "interpretation" and "interpret" (square
  3207 brackets) is no longer available.  Use locale expressions.
  3208 
  3209 - When converting proof scripts, mandatory qualifiers in
  3210 'interpretation' and 'interpret' should be retained by default, even
  3211 if this is an INCOMPATIBILITY compared to former behavior.  In the
  3212 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  3213 in locale expressions range over a single locale instance only.
  3214 
  3215 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  3216 In existing theorem specifications replace the includes element by the
  3217 respective context elements of the included locale, omitting those
  3218 that are already present in the theorem specification.  Multiple
  3219 assume elements of a locale should be replaced by a single one
  3220 involving the locale predicate.  In the proof body, declarations (most
  3221 notably theorems) may be regained by interpreting the respective
  3222 locales in the proof context as required (command "interpret").
  3223 
  3224 If using "includes" in replacement of a target solely because the
  3225 parameter types in the theorem are not as general as in the target,
  3226 consider declaring a new locale with additional type constraints on
  3227 the parameters (context element "constrains").
  3228 
  3229 - Discontinued "locale (open)".  INCOMPATIBILITY.
  3230 
  3231 - Locale interpretation commands no longer attempt to simplify goal.
  3232 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  3233 methods intro_locales and unfold_locales to clarify.
  3234 
  3235 - Locale interpretation commands no longer accept interpretation
  3236 attributes.  INCOMPATIBILITY.
  3237 
  3238 * Class declaration: so-called "base sort" must not be given in import
  3239 list any longer, but is inferred from the specification.  Particularly
  3240 in HOL, write
  3241 
  3242     class foo = ...
  3243 
  3244 instead of
  3245 
  3246     class foo = type + ...
  3247 
  3248 * Class target: global versions of theorems stemming do not carry a
  3249 parameter prefix any longer.  INCOMPATIBILITY.
  3250 
  3251 * Class 'instance' command no longer accepts attached definitions.
  3252 INCOMPATIBILITY, use proper 'instantiation' target instead.
  3253 
  3254 * Recovered hiding of consts, which was accidentally broken in
  3255 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  3256 makes c inaccessible; consider using ``hide (open) const c'' instead.
  3257 
  3258 * Slightly more coherent Pure syntax, with updated documentation in
  3259 isar-ref manual.  Removed locales meta_term_syntax and
  3260 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  3261 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  3262 directly in regular applications.
  3263 
  3264 * There is a new syntactic category "float_const" for signed decimal
  3265 fractions (e.g. 123.45 or -123.45).
  3266 
  3267 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  3268 interface with 'setup' command instead.
  3269 
  3270 * Command 'local_setup' is similar to 'setup', but operates on a local
  3271 theory context.
  3272 
  3273 * The 'axiomatization' command now only works within a global theory
  3274 context.  INCOMPATIBILITY.
  3275 
  3276 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  3277 hypotheses.  Sorts required in the course of reasoning need to be
  3278 covered by the constraints in the initial statement, completed by the
  3279 type instance information of the background theory.  Non-trivial sort
  3280 hypotheses, which rarely occur in practice, may be specified via
  3281 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  3282 
  3283   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  3284 
  3285 The result contains an implicit sort hypotheses as before --
  3286 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  3287 normalization.
  3288 
  3289 * Generalized Isar history, with support for linear undo, direct state
  3290 addressing etc.
  3291 
  3292 * Changed defaults for unify configuration options:
  3293 
  3294   unify_trace_bound = 50 (formerly 25)
  3295   unify_search_bound = 60 (formerly 30)
  3296 
  3297 * Different bookkeeping for code equations (INCOMPATIBILITY):
  3298 
  3299   a) On theory merge, the last set of code equations for a particular
  3300      constant is taken (in accordance with the policy applied by other
  3301      parts of the code generator framework).
  3302 
  3303   b) Code equations stemming from explicit declarations (e.g. code
  3304      attribute) gain priority over default code equations stemming
  3305      from definition, primrec, fun etc.
  3306 
  3307 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  3308 
  3309 * Unified theorem tables for both code generators.  Thus [code
  3310 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  3311 
  3312 * Command 'find_consts' searches for constants based on type and name
  3313 patterns, e.g.
  3314 
  3315     find_consts "_ => bool"
  3316 
  3317 By default, matching is against subtypes, but it may be restricted to
  3318 the whole type.  Searching by name is possible.  Multiple queries are
  3319 conjunctive and queries may be negated by prefixing them with a
  3320 hyphen:
  3321 
  3322     find_consts strict: "_ => bool" name: "Int" -"int => int"
  3323 
  3324 * New 'find_theorems' criterion "solves" matches theorems that
  3325 directly solve the current goal (modulo higher-order unification).
  3326 
  3327 * Auto solve feature for main theorem statements: whenever a new goal
  3328 is stated, "find_theorems solves" is called; any theorems that could
  3329 solve the lemma directly are listed as part of the goal state.
  3330 Cf. associated options in Proof General Isabelle settings menu,
  3331 enabled by default, with reasonable timeout for pathological cases of
  3332 higher-order unification.
  3333 
  3334 
  3335 *** Document preparation ***
  3336 
  3337 * Antiquotation @{lemma} now imitates a regular terminal proof,
  3338 demanding keyword 'by' and supporting the full method expression
  3339 syntax just like the Isar command 'by'.
  3340 
  3341 
  3342 *** HOL ***
  3343 
  3344 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  3345 points Main and Complex_Main remain as before.
  3346 
  3347 * Logic image HOL-Plain provides a minimal HOL with the most important
  3348 tools available (inductive, datatype, primrec, ...).  This facilitates
  3349 experimentation and tool development.  Note that user applications
  3350 (and library theories) should never refer to anything below theory
  3351 Main, as before.
  3352 
  3353 * Logic image HOL-Main stops at theory Main, and thus facilitates
  3354 experimentation due to shorter build times.
  3355 
  3356 * Logic image HOL-NSA contains theories of nonstandard analysis which
  3357 were previously part of former HOL-Complex.  Entry point Hyperreal
  3358 remains valid, but theories formerly using Complex_Main should now use
  3359 new entry point Hypercomplex.
  3360 
  3361 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  3362 Posix processes.  Avoids potentially expensive forking of the ML
  3363 process.  New thread-based implementation also works on non-Unix
  3364 platforms (Cygwin).  Provers are no longer hardwired, but defined
  3365 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  3366 commands are covered in the isar-ref manual.
  3367 
  3368 * Wrapper scripts for remote SystemOnTPTP service allows to use
  3369 sledgehammer without local ATP installation (Vampire etc.). Other
  3370 provers may be included via suitable ML wrappers, see also
  3371 src/HOL/ATP_Linkup.thy.
  3372 
  3373 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  3374 menu.
  3375 
  3376 * The metis method no longer fails because the theorem is too trivial
  3377 (contains the empty clause).
  3378 
  3379 * The metis method now fails in the usual manner, rather than raising
  3380 an exception, if it determines that it cannot prove the theorem.
  3381 
  3382 * Method "coherent" implements a prover for coherent logic (see also
  3383 src/Tools/coherent.ML).
  3384 
  3385 * Constants "undefined" and "default" replace "arbitrary".  Usually
  3386 "undefined" is the right choice to replace "arbitrary", though
  3387 logically there is no difference.  INCOMPATIBILITY.
  3388 
  3389 * Command "value" now integrates different evaluation mechanisms.  The
  3390 result of the first successful evaluation mechanism is printed.  In
  3391 square brackets a particular named evaluation mechanisms may be
  3392 specified (currently, [SML], [code] or [nbe]).  See further
  3393 src/HOL/ex/Eval_Examples.thy.
  3394 
  3395 * Normalization by evaluation now allows non-leftlinear equations.
  3396 Declare with attribute [code nbe].
  3397 
  3398 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  3399 as the structured Isar versions "cases" and "induct", cf. the
  3400 corresponding "cases" and "induct" attributes.  Mutual induction rules
  3401 are now presented as a list of individual projections
  3402 (e.g. foo_bar.inducts for types foo and bar); the old format with
  3403 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  3404 rare situations a different rule is selected --- notably nested tuple
  3405 elimination instead of former prod.exhaust: use explicit (case_tac t
  3406 rule: prod.exhaust) here.
  3407 
  3408 * Attributes "cases", "induct", "coinduct" support "del" option.
  3409 
  3410 * Removed fact "case_split_thm", which duplicates "case_split".
  3411 
  3412 * The option datatype has been moved to a new theory Option.  Renamed
  3413 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  3414 
  3415 * New predicate "strict_mono" classifies strict functions on partial
  3416 orders.  With strict functions on linear orders, reasoning about
  3417 (in)equalities is facilitated by theorems "strict_mono_eq",
  3418 "strict_mono_less_eq" and "strict_mono_less".
  3419 
  3420 * Some set operations are now proper qualified constants with
  3421 authentic syntax.  INCOMPATIBILITY:
  3422 
  3423     op Int ~>   Set.Int
  3424     op Un ~>    Set.Un
  3425     INTER ~>    Set.INTER
  3426     UNION ~>    Set.UNION
  3427     Inter ~>    Set.Inter
  3428     Union ~>    Set.Union
  3429     {} ~>       Set.empty
  3430     UNIV ~>     Set.UNIV
  3431 
  3432 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  3433 theory Set.
  3434 
  3435 * Auxiliary class "itself" has disappeared -- classes without any
  3436 parameter are treated as expected by the 'class' command.
  3437 
  3438 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  3439 
  3440 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  3441 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  3442 
  3443 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  3444 method "approximation".  It proves formulas on real values by using
  3445 interval arithmetic.  In the formulas are also the transcendental
  3446 functions sin, cos, tan, atan, ln, exp and the constant pi are
  3447 allowed. For examples see
  3448 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  3449 
  3450 * Theory "Reflection" now resides in HOL/Library.
  3451 
  3452 * Entry point to Word library now simply named "Word".
  3453 INCOMPATIBILITY.
  3454 
  3455 * Made source layout more coherent with logical distribution
  3456 structure:
  3457 
  3458     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  3459     src/HOL/Library/Code_Message.thy ~> src/HOL/
  3460     src/HOL/Library/GCD.thy ~> src/HOL/
  3461     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  3462     src/HOL/Library/Parity.thy ~> src/HOL/
  3463     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  3464     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  3465     src/HOL/Real/Lubs.thy ~> src/HOL/
  3466     src/HOL/Real/PReal.thy ~> src/HOL/
  3467     src/HOL/Real/Rational.thy ~> src/HOL/
  3468     src/HOL/Real/RComplete.thy ~> src/HOL/
  3469     src/HOL/Real/RealDef.thy ~> src/HOL/
  3470     src/HOL/Real/RealPow.thy ~> src/HOL/
  3471     src/HOL/Real/Real.thy ~> src/HOL/
  3472     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  3473     src/HOL/Complex/Complex.thy ~> src/HOL/
  3474     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  3475     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  3476     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  3477     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  3478     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  3479     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  3480     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  3481     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  3482     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  3483     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  3484     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  3485     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  3486     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  3487     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  3488     src/HOL/Real/Float ~> src/HOL/Library/
  3489     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  3490     src/HOL/Real/RealVector.thy ~> src/HOL/
  3491 
  3492     src/HOL/arith_data.ML ~> src/HOL/Tools
  3493     src/HOL/hologic.ML ~> src/HOL/Tools
  3494     src/HOL/simpdata.ML ~> src/HOL/Tools
  3495     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3496     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3497     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3498     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3499     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3500     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3501     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3502 
  3503     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3504     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3505     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3506     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3507     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3508     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3509 
  3510 * If methods "eval" and "evaluation" encounter a structured proof
  3511 state with !!/==>, only the conclusion is evaluated to True (if
  3512 possible), avoiding strange error messages.
  3513 
  3514 * Method "sizechange" automates termination proofs using (a
  3515 modification of) the size-change principle.  Requires SAT solver.  See
  3516 src/HOL/ex/Termination.thy for examples.
  3517 
  3518 * Simplifier: simproc for let expressions now unfolds if bound
  3519 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3520 
  3521 * Method "arith": Linear arithmetic now ignores all inequalities when
  3522 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3523 
  3524 * New attribute "arith" for facts that should always be used
  3525 automatically by arithmetic. It is intended to be used locally in
  3526 proofs, e.g.
  3527 
  3528   assumes [arith]: "x > 0"
  3529 
  3530 Global usage is discouraged because of possible performance impact.
  3531 
  3532 * New classes "top" and "bot" with corresponding operations "top" and
  3533 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3534 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3535 
  3536 * Changed definition lemma "less_fun_def" in order to provide an
  3537 instance for preorders on functions; use lemma "less_le" instead.
  3538 INCOMPATIBILITY.
  3539 
  3540 * Theory Orderings: class "wellorder" moved here, with explicit
  3541 induction rule "less_induct" as assumption.  For instantiation of
  3542 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3543 INCOMPATIBILITY.
  3544 
  3545 * Theory Orderings: added class "preorder" as superclass of "order".
  3546 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3547 etc. slightly changed.  Some theorems named order_class.* now named
  3548 preorder_class.*.
  3549 
  3550 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3551 "diag" to "Id_on".
  3552 
  3553 * Theory Finite_Set: added a new fold combinator of type
  3554 
  3555   ('a => 'b => 'b) => 'b => 'a set => 'b
  3556 
  3557 Occasionally this is more convenient than the old fold combinator
  3558 which is now defined in terms of the new one and renamed to
  3559 fold_image.
  3560 
  3561 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3562 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3563 extended with further lemmas!).  At the moment both still exist but
  3564 the former will disappear at some point.
  3565 
  3566 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3567 class recpower.  Type-specific simp rules for various recpower types
  3568 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3569 
  3570 rat_power_0    -> power_0
  3571 rat_power_Suc  -> power_Suc
  3572 realpow_0      -> power_0
  3573 realpow_Suc    -> power_Suc
  3574 complexpow_0   -> power_0
  3575 complexpow_Suc -> power_Suc
  3576 power_poly_0   -> power_0
  3577 power_poly_Suc -> power_Suc
  3578 
  3579 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3580 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3581 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3582 of lemmas from Divides has been generalized from nat to class
  3583 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3584 renames resulting from duplicate elimination:
  3585 
  3586     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3587     zero_dvd_iff ~>         dvd_0_left_iff
  3588     dvd_0 ~>                dvd_0_right
  3589     DIVISION_BY_ZERO_DIV ~> div_by_0
  3590     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3591     mult_div ~>             div_mult_self2_is_id
  3592     mult_mod ~>             mod_mult_self2_is_0
  3593 
  3594 * Theory IntDiv: removed many lemmas that are instances of class-based
  3595 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3596 rename old lemmas as follows:
  3597 
  3598 dvd_diff               -> nat_dvd_diff
  3599 dvd_zminus_iff         -> dvd_minus_iff
  3600 mod_add1_eq            -> mod_add_eq
  3601 mod_mult1_eq           -> mod_mult_right_eq
  3602 mod_mult1_eq'          -> mod_mult_left_eq
  3603 mod_mult_distrib_mod   -> mod_mult_eq
  3604 nat_mod_add_left_eq    -> mod_add_left_eq
  3605 nat_mod_add_right_eq   -> mod_add_right_eq
  3606 nat_mod_div_trivial    -> mod_div_trivial
  3607 nat_mod_mod_trivial    -> mod_mod_trivial
  3608 zdiv_zadd_self1        -> div_add_self1
  3609 zdiv_zadd_self2        -> div_add_self2
  3610 zdiv_zmult_self1       -> div_mult_self2_is_id
  3611 zdiv_zmult_self2       -> div_mult_self1_is_id
  3612 zdvd_triv_left         -> dvd_triv_left
  3613 zdvd_triv_right        -> dvd_triv_right
  3614 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3615 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3616 zmod_zadd_left_eq      -> mod_add_left_eq
  3617 zmod_zadd_right_eq     -> mod_add_right_eq
  3618 zmod_zadd_self1        -> mod_add_self1
  3619 zmod_zadd_self2        -> mod_add_self2
  3620 zmod_zadd1_eq          -> mod_add_eq
  3621 zmod_zdiff1_eq         -> mod_diff_eq
  3622 zmod_zdvd_zmod         -> mod_mod_cancel
  3623 zmod_zmod_cancel       -> mod_mod_cancel
  3624 zmod_zmult_self1       -> mod_mult_self2_is_0
  3625 zmod_zmult_self2       -> mod_mult_self1_is_0
  3626 zmod_1                 -> mod_by_1
  3627 zdiv_1                 -> div_by_1
  3628 zdvd_abs1              -> abs_dvd_iff
  3629 zdvd_abs2              -> dvd_abs_iff
  3630 zdvd_refl              -> dvd_refl
  3631 zdvd_trans             -> dvd_trans
  3632 zdvd_zadd              -> dvd_add
  3633 zdvd_zdiff             -> dvd_diff
  3634 zdvd_zminus_iff        -> dvd_minus_iff
  3635 zdvd_zminus2_iff       -> minus_dvd_iff
  3636 zdvd_zmultD            -> dvd_mult_right
  3637 zdvd_zmultD2           -> dvd_mult_left
  3638 zdvd_zmult_mono        -> mult_dvd_mono
  3639 zdvd_0_right           -> dvd_0_right
  3640 zdvd_0_left            -> dvd_0_left_iff
  3641 zdvd_1_left            -> one_dvd
  3642 zminus_dvd_iff         -> minus_dvd_iff
  3643 
  3644 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3645 
  3646 * The real numbers offer decimal input syntax: 12.34 is translated
  3647 into 1234/10^2. This translation is not reversed upon output.
  3648 
  3649 * Theory Library/Polynomial defines an abstract type 'a poly of
  3650 univariate polynomials with coefficients of type 'a.  In addition to
  3651 the standard ring operations, it also supports div and mod.  Code
  3652 generation is also supported, using list-style constructors.
  3653 
  3654 * Theory Library/Inner_Product defines a class of real_inner for real
  3655 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3656 => real.  Class real_inner is a subclass of real_normed_vector from
  3657 theory RealVector.
  3658 
  3659 * Theory Library/Product_Vector provides instances for the product
  3660 type 'a * 'b of several classes from RealVector and Inner_Product.
  3661 Definitions of addition, subtraction, scalar multiplication, norms,
  3662 and inner products are included.
  3663 
  3664 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3665 addition to the field operations, numerals and case syntax are also
  3666 supported.
  3667 
  3668 * Theory Library/Diagonalize provides constructive version of Cantor's
  3669 first diagonalization argument.
  3670 
  3671 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3672 zlcm (for int); carried together from various gcd/lcm developements in
  3673 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3674 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3675 may recover tupled syntax as follows:
  3676 
  3677     hide (open) const gcd
  3678     abbreviation gcd where
  3679       "gcd == (%(a, b). GCD.gcd a b)"
  3680     notation (output)
  3681       GCD.gcd ("gcd '(_, _')")
  3682 
  3683 The same works for lcm, zgcd, zlcm.
  3684 
  3685 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3686 instantiations for algebraic structures.  Removed some duplicate
  3687 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3688 
  3689 * ML antiquotation @{code} takes a constant as argument and generates
  3690 corresponding code in background and inserts name of the corresponding
  3691 resulting ML value/function/datatype constructor binding in place.
  3692 All occurrences of @{code} with a single ML block are generated
  3693 simultaneously.  Provides a generic and safe interface for
  3694 instrumentalizing code generation.  See
  3695 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3696 In future you ought to refrain from ad-hoc compiling generated SML
  3697 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3698 cannot refer to constants for which user-defined serializations are
  3699 set.  Refer to the corresponding ML counterpart directly in that
  3700 cases.
  3701 
  3702 * Command 'rep_datatype': instead of theorem names the command now
  3703 takes a list of terms denoting the constructors of the type to be
  3704 represented as datatype.  The characteristic theorems have to be
  3705 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3706 have disappeared in favour of existing ones:
  3707 
  3708     unit_induct                 ~> unit.induct
  3709     prod_induct                 ~> prod.induct
  3710     sum_induct                  ~> sum.induct
  3711     Suc_Suc_eq                  ~> nat.inject
  3712     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3713 
  3714 
  3715 *** HOL-Algebra ***
  3716 
  3717 * New locales for orders and lattices where the equivalence relation
  3718 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3719 locales use a record structure with field eq for the equivalence.
  3720 
  3721 * New theory of factorial domains.
  3722 
  3723 * Units_l_inv and Units_r_inv are now simp rules by default.
  3724 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3725 and/or r_inv will now also require deletion of these lemmas.
  3726 
  3727 * Renamed the following theorems, INCOMPATIBILITY:
  3728 
  3729 UpperD ~> Upper_memD
  3730 LowerD ~> Lower_memD
  3731 least_carrier ~> least_closed
  3732 greatest_carrier ~> greatest_closed
  3733 greatest_Lower_above ~> greatest_Lower_below
  3734 one_zero ~> carrier_one_zero
  3735 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3736 
  3737 
  3738 *** HOL-Nominal ***
  3739 
  3740 * Nominal datatypes can now contain type-variables.
  3741 
  3742 * Commands 'nominal_inductive' and 'equivariance' work with local
  3743 theory targets.
  3744 
  3745 * Nominal primrec can now works with local theory targets and its
  3746 specification syntax now conforms to the general format as seen in
  3747 'inductive' etc.
  3748 
  3749 * Method "perm_simp" honours the standard simplifier attributes
  3750 (no_asm), (no_asm_use) etc.
  3751 
  3752 * The new predicate #* is defined like freshness, except that on the
  3753 left hand side can be a set or list of atoms.
  3754 
  3755 * Experimental command 'nominal_inductive2' derives strong induction
  3756 principles for inductive definitions.  In contrast to
  3757 'nominal_inductive', which can only deal with a fixed number of
  3758 binders, it can deal with arbitrary expressions standing for sets of
  3759 atoms to be avoided.  The only inductive definition we have at the
  3760 moment that needs this generalisation is the typing rule for Lets in
  3761 the algorithm W:
  3762 
  3763  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3764  -----------------------------------------------------------------
  3765          Gamma |- Let x be t1 in t2 : T2
  3766 
  3767 In this rule one wants to avoid all the binders that are introduced by
  3768 "close Gamma T1".  We are looking for other examples where this
  3769 feature might be useful.  Please let us know.
  3770 
  3771 
  3772 *** HOLCF ***
  3773 
  3774 * Reimplemented the simplification procedure for proving continuity
  3775 subgoals.  The new simproc is extensible; users can declare additional
  3776 continuity introduction rules with the attribute [cont2cont].
  3777 
  3778 * The continuity simproc now uses a different introduction rule for
  3779 solving continuity subgoals on terms with lambda abstractions.  In
  3780 some rare cases the new simproc may fail to solve subgoals that the
  3781 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3782 Potential INCOMPATIBILITY.
  3783 
  3784 * Command 'fixrec': specification syntax now conforms to the general
  3785 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3786 examples.  INCOMPATIBILITY.
  3787 
  3788 
  3789 *** ZF ***
  3790 
  3791 * Proof of Zorn's Lemma for partial orders.
  3792 
  3793 
  3794 *** ML ***
  3795 
  3796 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3797 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3798 depends on multithreading, so timouts will not work before Poly/ML
  3799 5.2.1!
  3800 
  3801 * High-level support for concurrent ML programming, see
  3802 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3803 particularly convenient to organize independent functional
  3804 computations.  The concept of "synchronized variables" provides a
  3805 higher-order interface for components with shared state, avoiding the
  3806 delicate details of mutexes and condition variables.  (Requires
  3807 Poly/ML 5.2.1 or later.)
  3808 
  3809 * ML bindings produced via Isar commands are stored within the Isar
  3810 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3811 become thread-safe and work with undo as expected (concerning
  3812 top-level bindings, not side-effects on global references).
  3813 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3814 compiler at runtime; really global bindings need to be given outside a
  3815 theory.  (Requires Poly/ML 5.2 or later.)
  3816 
  3817 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3818 context.  Top-level ML bindings are stored within the proof context in
  3819 a purely sequential fashion, disregarding the nested proof structure.
  3820 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3821 proof.  (Requires Poly/ML 5.2 or later.)
  3822 
  3823 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3824 and Method.setup, as well as Isar commands 'attribute_setup' and
  3825 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3826 existing code accordingly, or use plain 'setup' together with old
  3827 Method.add_method.
  3828 
  3829 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3830 to 'a -> thm, while results are always tagged with an authentic oracle
  3831 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3832 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3833 accordingly.  Note that extra performance may be gained by producing
  3834 the cterm carefully, avoiding slow Thm.cterm_of.
  3835 
  3836 * Simplified interface for defining document antiquotations via
  3837 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3838 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3839 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3840 examples.
  3841 
  3842 * More systematic treatment of long names, abstract name bindings, and
  3843 name space operations.  Basic operations on qualified names have been
  3844 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3845 Long_Name.append.  Old type bstring has been mostly replaced by
  3846 abstract type binding (see structure Binding), which supports precise
  3847 qualification by packages and local theory targets, as well as proper
  3848 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3849 bstring values into Binding.name, or better pass through abstract
  3850 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3851 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3852 
  3853 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3854 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3855 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3856 
  3857 * Disposed old type and term read functions (Sign.read_def_typ,
  3858 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3859 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3860 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3861 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3862 resort for legacy applications.
  3863 
  3864 * Disposed old declarations, tactics, tactic combinators that refer to
  3865 the simpset or claset of an implicit theory (such as Addsimps,
  3866 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3867 embedded ML text, or local_simpset_of with a proper context passed as
  3868 explicit runtime argument.
  3869 
  3870 * Rules and tactics that read instantiations (read_instantiate,
  3871 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3872 context, which is required for parsing and type-checking.  Moreover,
  3873 the variables are specified as plain indexnames, not string encodings
  3874 thereof.  INCOMPATIBILITY.
  3875 
  3876 * Generic Toplevel.add_hook interface allows to analyze the result of
  3877 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3878 for theorem dependency output of transactions resulting in a new
  3879 theory state.
  3880 
  3881 * ML antiquotations: block-structured compilation context indicated by
  3882 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3883 
  3884   @{binding name}                         - basic name binding
  3885   @{let ?pat = term}                      - term abbreviation (HO matching)
  3886   @{note name = fact}                     - fact abbreviation
  3887   @{thm fact}                             - singleton fact (with attributes)
  3888   @{thms fact}                            - general fact (with attributes)
  3889   @{lemma prop by method}                 - singleton goal
  3890   @{lemma prop by meth1 meth2}            - singleton goal
  3891   @{lemma prop1 ... propN by method}      - general goal
  3892   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3893   @{lemma (open) ...}                     - open derivation
  3894 
  3895 
  3896 *** System ***
  3897 
  3898 * The Isabelle "emacs" tool provides a specific interface to invoke
  3899 Proof General / Emacs, with more explicit failure if that is not
  3900 installed (the old isabelle-interface script silently falls back on
  3901 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3902 installation location of the Proof General distribution.
  3903 
  3904 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3905 the Isabelle process into a JVM/Scala application.  See
  3906 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3907 process wrapper has been discontinued.)
  3908 
  3909 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3910 
  3911 * Various status messages (with exact source position information) are
  3912 emitted, if proper markup print mode is enabled.  This allows
  3913 user-interface components to provide detailed feedback on internal
  3914 prover operations.
  3915 
  3916 
  3917 
  3918 New in Isabelle2008 (June 2008)
  3919 -------------------------------
  3920 
  3921 *** General ***
  3922 
  3923 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3924 and updated, with formally checked references as hyperlinks.
  3925 
  3926 * Theory loader: use_thy (and similar operations) no longer set the
  3927 implicit ML context, which was occasionally hard to predict and in
  3928 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3929 provides a proper context already.
  3930 
  3931 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3932 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3933 'use' within a theory file will do the job.
  3934 
  3935 * Name space merge now observes canonical order, i.e. the second space
  3936 is inserted into the first one, while existing entries in the first
  3937 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3938 swap theory imports.
  3939 
  3940 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3941 INCOMPATIBILITY in identifier syntax etc.
  3942 
  3943 * Outer syntax: string tokens no longer admit escaped white space,
  3944 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3945 white space without escapes.
  3946 
  3947 * Outer syntax: string tokens may contain arbitrary character codes
  3948 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3949 "foo_bar".
  3950 
  3951 
  3952 *** Pure ***
  3953 
  3954 * Context-dependent token translations.  Default setup reverts locally
  3955 fixed variables, and adds hilite markup for undeclared frees.
  3956 
  3957 * Unused theorems can be found using the new command 'unused_thms'.
  3958 There are three ways of invoking it:
  3959 
  3960 (1) unused_thms
  3961      Only finds unused theorems in the current theory.
  3962 
  3963 (2) unused_thms thy_1 ... thy_n -
  3964      Finds unused theorems in the current theory and all of its ancestors,
  3965      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3966 
  3967 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3968      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3969      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3970      their ancestors.
  3971 
  3972 In order to increase the readability of the list produced by
  3973 unused_thms, theorems that have been created by a particular instance
  3974 of a theory command such as 'inductive' or 'function' are considered
  3975 to belong to the same "group", meaning that if at least one theorem in
  3976 this group is used, the other theorems in the same group are no longer
  3977 reported as unused.  Moreover, if all theorems in the group are
  3978 unused, only one theorem in the group is displayed.
  3979 
  3980 Note that proof objects have to be switched on in order for
  3981 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3982 usually the case when using Proof General with the default settings).
  3983 
  3984 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3985 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3986 duplicate fact bindings, or even accidental fact duplications.  Note
  3987 that tools may maintain dynamically scoped facts systematically, using
  3988 PureThy.add_thms_dynamic.
  3989 
  3990 * Command 'hide' now allows to hide from "fact" name space as well.
  3991 
  3992 * Eliminated destructive theorem database, simpset, claset, and
  3993 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3994 update of theories within ML code.
  3995 
  3996 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3997 INCOMPATIBILITY, object-logics depending on former Pure require
  3998 additional setup PureThy.old_appl_syntax_setup; object-logics
  3999 depending on former CPure need to refer to Pure.
  4000 
  4001 * Commands 'use' and 'ML' are now purely functional, operating on
  4002 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  4003 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  4004 INCOMPATIBILITY.
  4005 
  4006 * Command 'setup': discontinued implicit version with ML reference.
  4007 
  4008 * Instantiation target allows for simultaneous specification of class
  4009 instance operations together with an instantiation proof.
  4010 Type-checking phase allows to refer to class operations uniformly.
  4011 See src/HOL/Complex/Complex.thy for an Isar example and
  4012 src/HOL/Library/Eval.thy for an ML example.
  4013 
  4014 * Indexing of literal facts: be more serious about including only
  4015 facts from the visible specification/proof context, but not the
  4016 background context (locale etc.).  Affects `prop` notation and method
  4017 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  4018 situations.
  4019 
  4020 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  4021 "(open)" option, which used to expose internal bound variables to the
  4022 proof text.
  4023 
  4024 * Isar statements: removed obsolete case "rule_context".
  4025 INCOMPATIBILITY, better use explicit fixes/assumes.
  4026 
  4027 * Locale proofs: default proof step now includes 'unfold_locales';
  4028 hence 'proof' without argument may be used to unfold locale
  4029 predicates.
  4030 
  4031 
  4032 *** Document preparation ***
  4033 
  4034 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  4035 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  4036 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  4037 spot); renamed link color from "darkblue" to "linkcolor" (default
  4038 value unchanged, can be redefined via \definecolor); no longer sets
  4039 "a4paper" option (unnecessary or even intrusive).
  4040 
  4041 * Antiquotation @{lemma A method} proves proposition A by the given
  4042 method (either a method name or a method name plus (optional) method
  4043 arguments in parentheses) and prints A just like @{prop A}.
  4044 
  4045 
  4046 *** HOL ***
  4047 
  4048 * New primrec package.  Specification syntax conforms in style to
  4049 definition/function/....  No separate induction rule is provided.  The
  4050 "primrec" command distinguishes old-style and new-style specifications
  4051 by syntax.  The former primrec package is now named OldPrimrecPackage.
  4052 When adjusting theories, beware: constants stemming from new-style
  4053 primrec specifications have authentic syntax.
  4054 
  4055 * Metis prover is now an order of magnitude faster, and also works
  4056 with multithreading.
  4057 
  4058 * Metis: the maximum number of clauses that can be produced from a
  4059 theorem is now given by the attribute max_clauses.  Theorems that
  4060 exceed this number are ignored, with a warning printed.
  4061 
  4062 * Sledgehammer no longer produces structured proofs by default. To
  4063 enable, declare [[sledgehammer_full = true]].  Attributes
  4064 reconstruction_modulus, reconstruction_sorts renamed
  4065 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  4066 
  4067 * Method "induct_scheme" derives user-specified induction rules
  4068 from well-founded induction and completeness of patterns. This factors
  4069 out some operations that are done internally by the function package
  4070 and makes them available separately.  See
  4071 src/HOL/ex/Induction_Scheme.thy for examples.
  4072 
  4073 * More flexible generation of measure functions for termination
  4074 proofs: Measure functions can be declared by proving a rule of the
  4075 form "is_measure f" and giving it the [measure_function] attribute.
  4076 The "is_measure" predicate is logically meaningless (always true), and
  4077 just guides the heuristic.  To find suitable measure functions, the
  4078 termination prover sets up the goal "is_measure ?f" of the appropriate
  4079 type and generates all solutions by prolog-style backwards proof using
  4080 the declared rules.
  4081 
  4082 This setup also deals with rules like 
  4083 
  4084   "is_measure f ==> is_measure (list_size f)"
  4085 
  4086 which accommodates nested datatypes that recurse through lists.
  4087 Similar rules are predeclared for products and option types.
  4088 
  4089 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  4090 
  4091   INCOMPATIBILITIES:
  4092 
  4093   - Definitions of overloaded constants on sets have to be replaced by
  4094     definitions on => and bool.
  4095 
  4096   - Some definitions of overloaded operators on sets can now be proved
  4097     using the definitions of the operators on => and bool.  Therefore,
  4098     the following theorems have been renamed:
  4099 
  4100       subset_def   -> subset_eq
  4101       psubset_def  -> psubset_eq
  4102       set_diff_def -> set_diff_eq
  4103       Compl_def    -> Compl_eq
  4104       Sup_set_def  -> Sup_set_eq
  4105       Inf_set_def  -> Inf_set_eq
  4106       sup_set_def  -> sup_set_eq
  4107       inf_set_def  -> inf_set_eq
  4108 
  4109   - Due to the incompleteness of the HO unification algorithm, some
  4110     rules such as subst may require manual instantiation, if some of
  4111     the unknowns in the rule is a set.
  4112 
  4113   - Higher order unification and forward proofs:
  4114     The proof pattern
  4115 
  4116       have "P (S::'a set)" <...>
  4117       then have "EX S. P S" ..
  4118 
  4119     no longer works (due to the incompleteness of the HO unification
  4120     algorithm) and must be replaced by the pattern
  4121 
  4122       have "EX S. P S"
  4123       proof
  4124         show "P S" <...>
  4125       qed
  4126 
  4127   - Calculational reasoning with subst (or similar rules):
  4128     The proof pattern
  4129 
  4130       have "P (S::'a set)" <...>
  4131       also have "S = T" <...>
  4132       finally have "P T" .
  4133 
  4134     no longer works (for similar reasons as the previous example) and
  4135     must be replaced by something like
  4136 
  4137       have "P (S::'a set)" <...>
  4138       moreover have "S = T" <...>
  4139       ultimately have "P T" by simp
  4140 
  4141   - Tactics or packages written in ML code:
  4142     Code performing pattern matching on types via
  4143 
  4144       Type ("set", [T]) => ...
  4145 
  4146     must be rewritten. Moreover, functions like strip_type or
  4147     binder_types no longer return the right value when applied to a
  4148     type of the form
  4149 
  4150       T1 => ... => Tn => U => bool
  4151 
  4152     rather than
  4153 
  4154       T1 => ... => Tn => U set
  4155 
  4156 * Merged theories Wellfounded_Recursion, Accessible_Part and
  4157 Wellfounded_Relations to theory Wellfounded.
  4158 
  4159 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  4160 
  4161 * Class finite no longer treats UNIV as class parameter.  Use class
  4162 enum from theory Library/Enum instead to achieve a similar effect.
  4163 INCOMPATIBILITY.
  4164 
  4165 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  4166 and "Cons".  INCOMPATIBILITY.
  4167 
  4168 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  4169 Potential INCOMPATIBILITY.
  4170 
  4171 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  4172 injective_fst_snd removed, use split_eta and prod_eqI instead.
  4173 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  4174 
  4175 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  4176 the same name in theory Orderings:
  4177 
  4178   less_trans
  4179   less_linear
  4180   le_imp_less_or_eq
  4181   le_less_trans
  4182   less_le_trans
  4183   less_not_sym
  4184   less_asym
  4185 
  4186 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  4187 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  4188 and different variable names.
  4189 
  4190 * Library/Option_ord.thy: Canonical order on option type.
  4191 
  4192 * Library/RBT.thy: Red-black trees, an efficient implementation of
  4193 finite maps.
  4194 
  4195 * Library/Countable.thy: Type class for countable types.
  4196 
  4197 * Theory Int: The representation of numerals has changed.  The infix
  4198 operator BIT and the bit datatype with constructors B0 and B1 have
  4199 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  4200 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  4201 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  4202 accordingly.
  4203 
  4204 * Theory Nat: definition of <= and < on natural numbers no longer
  4205 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  4206 le_def and less_def have disappeared.  Consider lemmas not_less
  4207 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  4208 
  4209 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  4210 (whose purpose mainly is for various fold_set functionals) have been
  4211 abandoned in favor of the existing algebraic classes
  4212 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  4213 lower_semilattice (resp. upper_semilattice) and linorder.
  4214 INCOMPATIBILITY.
  4215 
  4216 * Theory Transitive_Closure: induct and cases rules now declare proper
  4217 case_names ("base" and "step").  INCOMPATIBILITY.
  4218 
  4219 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  4220 lattices.  The form set-specific version is available as
  4221 Inductive.lfp_ordinal_induct_set.
  4222 
  4223 * Renamed theorems "power.simps" to "power_int.simps".
  4224 INCOMPATIBILITY.
  4225 
  4226 * Class semiring_div provides basic abstract properties of semirings
  4227 with division and modulo operations.  Subsumes former class dvd_mod.
  4228 
  4229 * Merged theories IntDef, Numeral and IntArith into unified theory
  4230 Int.  INCOMPATIBILITY.
  4231 
  4232 * Theory Library/Code_Index: type "index" now represents natural
  4233 numbers rather than integers.  INCOMPATIBILITY.
  4234 
  4235 * New class "uminus" with operation "uminus" (split of from class
  4236 "minus" which now only has operation "minus", binary).
  4237 INCOMPATIBILITY.
  4238 
  4239 * Constants "card", "internal_split", "option_map" now with authentic
  4240 syntax.  INCOMPATIBILITY.
  4241 
  4242 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  4243 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  4244 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  4245 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  4246 Sup_set_def, le_def, less_def, option_map_def now with object
  4247 equality.  INCOMPATIBILITY.
  4248 
  4249 * Records. Removed K_record, and replaced it by pure lambda term
  4250 %x. c. The simplifier setup is now more robust against eta expansion.
  4251 INCOMPATIBILITY: in cases explicitly referring to K_record.
  4252 
  4253 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  4254 
  4255 * Library/ListVector: new theory of arithmetic vector operations.
  4256 
  4257 * Library/Order_Relation: new theory of various orderings as sets of
  4258 pairs.  Defines preorders, partial orders, linear orders and
  4259 well-orders on sets and on types.
  4260 
  4261 
  4262 *** ZF ***
  4263 
  4264 * Renamed some theories to allow to loading both ZF and HOL in the
  4265 same session:
  4266 
  4267   Datatype  -> Datatype_ZF
  4268   Inductive -> Inductive_ZF
  4269   Int       -> Int_ZF
  4270   IntDiv    -> IntDiv_ZF
  4271   Nat       -> Nat_ZF
  4272   List      -> List_ZF
  4273   Main      -> Main_ZF
  4274 
  4275 INCOMPATIBILITY: ZF theories that import individual theories below
  4276 Main might need to be adapted.  Regular theory Main is still
  4277 available, as trivial extension of Main_ZF.
  4278 
  4279 
  4280 *** ML ***
  4281 
  4282 * ML within Isar: antiquotation @{const name} or @{const
  4283 name(typargs)} produces statically-checked Const term.
  4284 
  4285 * Functor NamedThmsFun: data is available to the user as dynamic fact
  4286 (of the same name).  Removed obsolete print command.
  4287 
  4288 * Removed obsolete "use_legacy_bindings" function.
  4289 
  4290 * The ``print mode'' is now a thread-local value derived from a global
  4291 template (the former print_mode reference), thus access becomes
  4292 non-critical.  The global print_mode reference is for session
  4293 management only; user-code should use print_mode_value,
  4294 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  4295 
  4296 * Functions system/system_out provide a robust way to invoke external
  4297 shell commands, with propagation of interrupts (requires Poly/ML
  4298 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  4299 
  4300 
  4301 *** System ***
  4302 
  4303 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  4304 in accordance with Proof General 3.7, which prefers GNU emacs.
  4305 
  4306 * isatool tty runs Isabelle process with plain tty interaction;
  4307 optional line editor may be specified via ISABELLE_LINE_EDITOR
  4308 setting, the default settings attempt to locate "ledit" and "rlwrap".
  4309 
  4310 * isatool browser now works with Cygwin as well, using general
  4311 "javapath" function defined in Isabelle process environment.
  4312 
  4313 * YXML notation provides a simple and efficient alternative to
  4314 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  4315 isatool yxml as described in the Isabelle system manual.
  4316 
  4317 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  4318 provides general wrapper for managing an Isabelle process in a robust
  4319 fashion, with ``cooked'' output from stdin/stderr.
  4320 
  4321 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  4322 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  4323 
  4324 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  4325 way of changing the user's settings is via
  4326 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  4327 script.
  4328 
  4329 * Multithreading.max_threads := 0 refers to the number of actual CPU
  4330 cores of the underlying machine, which is a good starting point for
  4331 optimal performance tuning.  The corresponding usedir option -M allows
  4332 "max" as an alias for "0".  WARNING: does not work on certain versions
  4333 of Mac OS (with Poly/ML 5.1).
  4334 
  4335 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  4336 adverse effect of Isabelle flooding interactive front-ends (notably
  4337 ProofGeneral / XEmacs).
  4338 
  4339 
  4340 
  4341 New in Isabelle2007 (November 2007)
  4342 -----------------------------------
  4343 
  4344 *** General ***
  4345 
  4346 * More uniform information about legacy features, notably a
  4347 warning/error of "Legacy feature: ...", depending on the state of the
  4348 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  4349 legacy features will disappear eventually.
  4350 
  4351 * Theory syntax: the header format ``theory A = B + C:'' has been
  4352 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  4353 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  4354 
  4355 * Theory syntax: the old non-Isar theory file format has been
  4356 discontinued altogether.  Note that ML proof scripts may still be used
  4357 with Isar theories; migration is usually quite simple with the ML
  4358 function use_legacy_bindings.  INCOMPATIBILITY.
  4359 
  4360 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  4361 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  4362 quotes.
  4363 
  4364 * Theory loader: be more serious about observing the static theory
  4365 header specifications (including optional directories), but not the
  4366 accidental file locations of previously successful loads.  The strict
  4367 update policy of former update_thy is now already performed by
  4368 use_thy, so the former has been removed; use_thys updates several
  4369 theories simultaneously, just as 'imports' within a theory header
  4370 specification, but without merging the results.  Potential
  4371 INCOMPATIBILITY: may need to refine theory headers and commands
  4372 ROOT.ML which depend on load order.
  4373 
  4374 * Theory loader: optional support for content-based file
  4375 identification, instead of the traditional scheme of full physical
  4376 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  4377 (cf. the system manual).  The new scheme allows to work with
  4378 non-finished theories in persistent session images, such that source
  4379 files may be moved later on without requiring reloads.
  4380 
  4381 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4382 file (with the same base name as the theory) are considered a legacy
  4383 feature, which will disappear eventually. Even now, the theory loader
  4384 no longer maintains dependencies on such files.
  4385 
  4386 * Syntax: the scope for resolving ambiguities via type-inference is
  4387 now limited to individual terms, instead of whole simultaneous
  4388 specifications as before. This greatly reduces the complexity of the
  4389 syntax module and improves flexibility by separating parsing and
  4390 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  4391 'fixes' etc.) are required in rare situations.
  4392 
  4393 * Syntax: constants introduced by new-style packages ('definition',
  4394 'abbreviation' etc.) are passed through the syntax module in
  4395 ``authentic mode''. This means that associated mixfix annotations
  4396 really stick to such constants, independently of potential name space
  4397 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  4398 trees are represented slightly differently, may need to adapt syntax
  4399 translations accordingly. Use CONST marker in 'translations' and
  4400 @{const_syntax} antiquotation in 'parse_translation' etc.
  4401 
  4402 * Legacy goal package: reduced interface to the bare minimum required
  4403 to keep existing proof scripts running.  Most other user-level
  4404 functions are now part of the OldGoals structure, which is *not* open
  4405 by default (consider isatool expandshort before open OldGoals).
  4406 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  4407 these tend to cause confusion about the actual goal (!) context being
  4408 used here, which is not necessarily the same as the_context().
  4409 
  4410 * Command 'find_theorems': supports "*" wild-card in "name:"
  4411 criterion; "with_dups" option.  Certain ProofGeneral versions might
  4412 support a specific search form (see ProofGeneral/CHANGES).
  4413 
  4414 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  4415 by default, which means that "prems" (and also "fixed variables") are
  4416 suppressed from proof state output.  Note that the ProofGeneral
  4417 settings mechanism allows to change and save options persistently, but
  4418 older versions of Isabelle will fail to start up if a negative prems
  4419 limit is imposed.
  4420 
  4421 * Local theory targets may be specified by non-nested blocks of
  4422 ``context/locale/class ... begin'' followed by ``end''.  The body may
  4423 contain definitions, theorems etc., including any derived mechanism
  4424 that has been implemented on top of these primitives.  This concept
  4425 generalizes the existing ``theorem (in ...)'' towards more versatility
  4426 and scalability.
  4427 
  4428 * Proof General interface: proper undo of final 'end' command;
  4429 discontinued Isabelle/classic mode (ML proof scripts).
  4430 
  4431 
  4432 *** Document preparation ***
  4433 
  4434 * Added antiquotation @{theory name} which prints the given name,
  4435 after checking that it refers to a valid ancestor theory in the
  4436 current context.
  4437 
  4438 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  4439 check the given source text as ML type/structure, printing verbatim.
  4440 
  4441 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  4442 "c args == rhs" given in the current context.  (Any number of
  4443 arguments may be given on the LHS.)
  4444 
  4445 
  4446 *** Pure ***
  4447 
  4448 * The 'class' package offers a combination of axclass and locale to
  4449 achieve Haskell-like type classes in Isabelle.  Definitions and
  4450 theorems within a class context produce both relative results (with
  4451 implicit parameters according to the locale context), and polymorphic
  4452 constants with qualified polymorphism (according to the class
  4453 context).  Within the body context of a 'class' target, a separate
  4454 syntax layer ("user space type system") takes care of converting
  4455 between global polymorphic consts and internal locale representation.
  4456 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  4457 "isatool doc classes" provides a tutorial.
  4458 
  4459 * Generic code generator framework allows to generate executable
  4460 code for ML and Haskell (including Isabelle classes).  A short usage
  4461 sketch:
  4462 
  4463     internal compilation:
  4464         export_code <list of constants (term syntax)> in SML
  4465     writing SML code to a file:
  4466         export_code <list of constants (term syntax)> in SML <filename>
  4467     writing OCaml code to a file:
  4468         export_code <list of constants (term syntax)> in OCaml <filename>
  4469     writing Haskell code to a bunch of files:
  4470         export_code <list of constants (term syntax)> in Haskell <filename>
  4471 
  4472     evaluating closed propositions to True/False using code generation:
  4473         method ``eval''
  4474 
  4475 Reasonable default setup of framework in HOL.
  4476 
  4477 Theorem attributs for selecting and transforming function equations theorems:
  4478 
  4479     [code fun]:        select a theorem as function equation for a specific constant
  4480     [code fun del]:    deselect a theorem as function equation for a specific constant
  4481     [code inline]:     select an equation theorem for unfolding (inlining) in place
  4482     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  4483 
  4484 User-defined serializations (target in {SML, OCaml, Haskell}):
  4485 
  4486     code_const <and-list of constants (term syntax)>
  4487       {(target) <and-list of const target syntax>}+
  4488 
  4489     code_type <and-list of type constructors>
  4490       {(target) <and-list of type target syntax>}+
  4491 
  4492     code_instance <and-list of instances>
  4493       {(target)}+
  4494         where instance ::= <type constructor> :: <class>
  4495 
  4496     code_class <and_list of classes>
  4497       {(target) <and-list of class target syntax>}+
  4498         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4499 
  4500 code_instance and code_class only are effective to target Haskell.
  4501 
  4502 For example usage see src/HOL/ex/Codegenerator.thy and
  4503 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4504 generation from Isabelle/HOL theories is available via "isatool doc
  4505 codegen".
  4506 
  4507 * Code generator: consts in 'consts_code' Isar commands are now
  4508 referred to by usual term syntax (including optional type
  4509 annotations).
  4510 
  4511 * Command 'no_translations' removes translation rules from theory
  4512 syntax.
  4513 
  4514 * Overloaded definitions are now actually checked for acyclic
  4515 dependencies.  The overloading scheme is slightly more general than
  4516 that of Haskell98, although Isabelle does not demand an exact
  4517 correspondence to type class and instance declarations.
  4518 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4519 exotic versions of overloading -- at the discretion of the user!
  4520 
  4521 Polymorphic constants are represented via type arguments, i.e. the
  4522 instantiation that matches an instance against the most general
  4523 declaration given in the signature.  For example, with the declaration
  4524 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4525 as c(nat).  Overloading is essentially simultaneous structural
  4526 recursion over such type arguments.  Incomplete specification patterns
  4527 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4528 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4529 Command 'print_theory' outputs the normalized system of recursive
  4530 equations, see section "definitions".
  4531 
  4532 * Configuration options are maintained within the theory or proof
  4533 context (with name and type bool/int/string), providing a very simple
  4534 interface to a poor-man's version of general context data.  Tools may
  4535 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4536 these values using Config.get etc.  Users may change options via an
  4537 associated attribute of the same name.  This form of context
  4538 declaration works particularly well with commands 'declare' or
  4539 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4540 very easy to avoid global references, which would not observe Isar
  4541 toplevel undo/redo and fail to work with multithreading.
  4542 
  4543 Various global ML references of Pure and HOL have been turned into
  4544 configuration options:
  4545 
  4546   Unify.search_bound		unify_search_bound
  4547   Unify.trace_bound		unify_trace_bound
  4548   Unify.trace_simp		unify_trace_simp
  4549   Unify.trace_types		unify_trace_types
  4550   Simplifier.simp_depth_limit	simp_depth_limit
  4551   Blast.depth_limit		blast_depth_limit
  4552   DatatypeProp.dtK		datatype_distinctness_limit
  4553   fast_arith_neq_limit  	fast_arith_neq_limit
  4554   fast_arith_split_limit	fast_arith_split_limit
  4555 
  4556 * Named collections of theorems may be easily installed as context
  4557 data using the functor NamedThmsFun (see also
  4558 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4559 attributes; there is also a toplevel print command.  This facility is
  4560 just a common case of general context data, which is the preferred way
  4561 for anything more complex than just a list of facts in canonical
  4562 order.
  4563 
  4564 * Isar: command 'declaration' augments a local theory by generic
  4565 declaration functions written in ML.  This enables arbitrary content
  4566 being added to the context, depending on a morphism that tells the
  4567 difference of the original declaration context wrt. the application
  4568 context encountered later on.
  4569 
  4570 * Isar: proper interfaces for simplification procedures.  Command
  4571 'simproc_setup' declares named simprocs (with match patterns, and body
  4572 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4573 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4574 
  4575 * Isar: an extra pair of brackets around attribute declarations
  4576 abbreviates a theorem reference involving an internal dummy fact,
  4577 which will be ignored later --- only the effect of the attribute on
  4578 the background context will persist.  This form of in-place
  4579 declarations is particularly useful with commands like 'declare' and
  4580 'using', for example ``have A using [[simproc a]] by simp''.
  4581 
  4582 * Isar: method "assumption" (and implicit closing of subproofs) now
  4583 takes simple non-atomic goal assumptions into account: after applying
  4584 an assumption as a rule the resulting subgoals are solved by atomic
  4585 assumption steps.  This is particularly useful to finish 'obtain'
  4586 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4587 without referring to the original premise "!!x. P x ==> thesis" in the
  4588 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4589 more permissive.
  4590 
  4591 * Isar: implicit use of prems from the Isar proof context is
  4592 considered a legacy feature.  Common applications like ``have A .''
  4593 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4594 referencing facts explicitly here improves readability and
  4595 maintainability of proof texts.
  4596 
  4597 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4598 the obtained context from the course of reasoning!  For example:
  4599 
  4600   assume "EX x y. A x & B y"   -- "any previous fact"
  4601   then guess x and y by clarify
  4602 
  4603 This technique is potentially adventurous, depending on the facts and
  4604 proof tools being involved here.
  4605 
  4606 * Isar: known facts from the proof context may be specified as literal
  4607 propositions, using ASCII back-quote syntax.  This works wherever
  4608 named facts used to be allowed so far, in proof commands, proof
  4609 methods, attributes etc.  Literal facts are retrieved from the context
  4610 according to unification of type and term parameters.  For example,
  4611 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4612 theorems in the current context, then these are valid literal facts:
  4613 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4614 
  4615 There is also a proof method "fact" which does the same composition
  4616 for explicit goal states, e.g. the following proof texts coincide with
  4617 certain special cases of literal facts:
  4618 
  4619   have "A" by fact                 ==  note `A`
  4620   have "A ==> B" by fact           ==  note `A ==> B`
  4621   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4622   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4623 
  4624 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4625 outer syntax.  Thus symbolic identifiers may be used without
  4626 additional white space in declarations like this: ``assume *: A''.
  4627 
  4628 * Isar: 'print_facts' prints all local facts of the current context,
  4629 both named and unnamed ones.
  4630 
  4631 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4632 
  4633   def x == "t" and y == "u"
  4634 
  4635 * Isar: added command 'unfolding', which is structurally similar to
  4636 'using', but affects both the goal state and facts by unfolding given
  4637 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4638 'unfolded' attribute may be replaced by first-class proof text.
  4639 
  4640 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4641 and command 'unfolding' now all support object-level equalities
  4642 (potentially conditional).  The underlying notion of rewrite rule is
  4643 analogous to the 'rule_format' attribute, but *not* that of the
  4644 Simplifier (which is usually more generous).
  4645 
  4646 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4647 premises of a theorem by n. Useful in conjunction with drule.
  4648 
  4649 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4650 method expression within a sandbox consisting of the first N
  4651 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4652 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4653 simplifies all new goals that emerge from applying rule foo to the
  4654 originally first one.
  4655 
  4656 * Isar: schematic goals are no longer restricted to higher-order
  4657 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4658 expected.
  4659 
  4660 * Isar: the conclusion of a long theorem statement is now either
  4661 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4662 (essentially a disjunction of cases with local parameters and
  4663 assumptions).  The latter allows to express general elimination rules
  4664 adequately; in this notation common elimination rules look like this:
  4665 
  4666   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4667     assumes "EX x. P x"
  4668     obtains x where "P x"
  4669 
  4670   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4671     assumes "A & B"
  4672     obtains A and B
  4673 
  4674   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4675     assumes "A | B"
  4676     obtains
  4677       A
  4678     | B
  4679 
  4680 The subsequent classical rules even refer to the formal "thesis"
  4681 explicitly:
  4682 
  4683   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4684     obtains "~ thesis"
  4685 
  4686   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4687     obtains "thesis ==> something"
  4688 
  4689 The actual proof of an 'obtains' statement is analogous to that of the
  4690 Isar proof element 'obtain', only that there may be several cases.
  4691 Optional case names may be specified in parentheses; these will be
  4692 available both in the present proof and as annotations in the
  4693 resulting rule, for later use with the 'cases' method (cf. attribute
  4694 case_names).
  4695 
  4696 * Isar: the assumptions of a long theorem statement are available as
  4697 "assms" fact in the proof context.  This is more appropriate than the
  4698 (historical) "prems", which refers to all assumptions of the current
  4699 context, including those from the target locale, proof body etc.
  4700 
  4701 * Isar: 'print_statement' prints theorems from the current theory or
  4702 proof context in long statement form, according to the syntax of a
  4703 top-level lemma.
  4704 
  4705 * Isar: 'obtain' takes an optional case name for the local context
  4706 introduction rule (default "that").
  4707 
  4708 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4709 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4710 to occur.
  4711 
  4712 * Pure: syntax "CONST name" produces a fully internalized constant
  4713 according to the current context.  This is particularly useful for
  4714 syntax translations that should refer to internal constant
  4715 representations independently of name spaces.
  4716 
  4717 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4718 instead of "FOO ". This allows multiple binder declarations to coexist
  4719 in the same context.  INCOMPATIBILITY.
  4720 
  4721 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4722 primitive that also works in a locale context (both for constants and
  4723 fixed variables). Type declaration and internal syntactic representation
  4724 of given constants retrieved from the context. Likewise, the
  4725 'no_notation' command allows to remove given syntax annotations from the
  4726 current context.
  4727 
  4728 * Isar/locales: new derived specification elements 'axiomatization',
  4729 'definition', 'abbreviation', which support type-inference, admit
  4730 object-level specifications (equality, equivalence).  See also the
  4731 isar-ref manual.  Examples:
  4732 
  4733   axiomatization
  4734     eq  (infix "===" 50) where
  4735     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4736 
  4737   definition "f x y = x + y + 1"
  4738   definition g where "g x = f x x"
  4739 
  4740   abbreviation
  4741     neq  (infix "=!=" 50) where
  4742     "x =!= y == ~ (x === y)"
  4743 
  4744 These specifications may be also used in a locale context.  Then the
  4745 constants being introduced depend on certain fixed parameters, and the
  4746 constant name is qualified by the locale base name.  An internal
  4747 abbreviation takes care for convenient input and output, making the
  4748 parameters implicit and using the original short name.  See also
  4749 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4750 entities from a monomorphic theory.
  4751 
  4752 Presently, abbreviations are only available 'in' a target locale, but
  4753 not inherited by general import expressions.  Also note that
  4754 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4755 'translations' in common applications.  The "no_abbrevs" print mode
  4756 prevents folding of abbreviations in term output.
  4757 
  4758 Concrete syntax is attached to specified constants in internal form,
  4759 independently of name spaces.  The parse tree representation is
  4760 slightly different -- use 'notation' instead of raw 'syntax', and
  4761 'translations' with explicit "CONST" markup to accommodate this.
  4762 
  4763 * Pure/Isar: unified syntax for new-style specification mechanisms
  4764 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4765 full type inference and dummy patterns ("_").  For example:
  4766 
  4767   definition "K x _ = x"
  4768 
  4769   inductive conj for A B
  4770   where "A ==> B ==> conj A B"
  4771 
  4772 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4773 the current context.  Print mode "no_abbrevs" prevents inversion of
  4774 abbreviations on output.
  4775 
  4776 * Isar/locales: improved parameter handling: use of locales "var" and
  4777 "struct" no longer necessary; - parameter renamings are no longer
  4778 required to be injective.  For example, this allows to define
  4779 endomorphisms as locale endom = homom mult mult h.
  4780 
  4781 * Isar/locales: changed the way locales with predicates are defined.
  4782 Instead of accumulating the specification, the imported expression is
  4783 now an interpretation.  INCOMPATIBILITY: different normal form of
  4784 locale expressions.  In particular, in interpretations of locales with
  4785 predicates, goals repesenting already interpreted fragments are not
  4786 removed automatically.  Use methods `intro_locales' and
  4787 `unfold_locales'; see below.
  4788 
  4789 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4790 provide backward reasoning on locales predicates.  The methods are
  4791 aware of interpretations and discharge corresponding goals.
  4792 `intro_locales' is less aggressive then `unfold_locales' and does not
  4793 unfold predicates to assumptions.
  4794 
  4795 * Isar/locales: the order in which locale fragments are accumulated
  4796 has changed.  This enables to override declarations from fragments due
  4797 to interpretations -- for example, unwanted simp rules.
  4798 
  4799 * Isar/locales: interpretation in theories and proof contexts has been
  4800 extended.  One may now specify (and prove) equations, which are
  4801 unfolded in interpreted theorems.  This is useful for replacing
  4802 defined concepts (constants depending on locale parameters) by
  4803 concepts already existing in the target context.  Example:
  4804 
  4805   interpretation partial_order ["op <= :: [int, int] => bool"]
  4806     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4807 
  4808 Typically, the constant `partial_order.less' is created by a
  4809 definition specification element in the context of locale
  4810 partial_order.
  4811 
  4812 * Method "induct": improved internal context management to support
  4813 local fixes and defines on-the-fly. Thus explicit meta-level
  4814 connectives !!  and ==> are rarely required anymore in inductive goals
  4815 (using object-logic connectives for this purpose has been long
  4816 obsolete anyway). Common proof patterns are explained in
  4817 src/HOL/Induct/Common_Patterns.thy, see also
  4818 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4819 examples.
  4820 
  4821 * Method "induct": improved handling of simultaneous goals. Instead of
  4822 introducing object-level conjunction, the statement is now split into
  4823 several conclusions, while the corresponding symbolic cases are nested
  4824 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4825 see src/HOL/Induct/Common_Patterns.thy, for example.
  4826 
  4827 * Method "induct": mutual induction rules are now specified as a list
  4828 of rule sharing the same induction cases. HOL packages usually provide
  4829 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4830 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4831 mutual induction rules differently, i.e. like this:
  4832 
  4833   (induct rule: foo_bar.inducts)
  4834   (induct set: foo bar)
  4835   (induct pred: foo bar)
  4836   (induct type: foo bar)
  4837 
  4838 The ML function ProjectRule.projections turns old-style rules into the
  4839 new format.
  4840 
  4841 * Method "coinduct": dual of induction, see
  4842 src/HOL/Library/Coinductive_List.thy for various examples.
  4843 
  4844 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4845 considered a legacy feature.
  4846 
  4847 * Attribute "symmetric" produces result with standardized schematic
  4848 variables (index 0).  Potential INCOMPATIBILITY.
  4849 
  4850 * Simplifier: by default the simplifier trace only shows top level
  4851 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4852 default. Thus there is less danger of being flooded by the trace. The
  4853 trace indicates where parts have been suppressed.
  4854   
  4855 * Provers/classical: removed obsolete classical version of elim_format
  4856 attribute; classical elim/dest rules are now treated uniformly when
  4857 manipulating the claset.
  4858 
  4859 * Provers/classical: stricter checks to ensure that supplied intro,
  4860 dest and elim rules are well-formed; dest and elim rules must have at
  4861 least one premise.
  4862 
  4863 * Provers/classical: attributes dest/elim/intro take an optional
  4864 weight argument for the rule (just as the Pure versions).  Weights are
  4865 ignored by automated tools, but determine the search order of single
  4866 rule steps.
  4867 
  4868 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4869 where the body does not mention the bound variable.  Note that dummy
  4870 patterns implicitly depend on their context of bounds, which makes
  4871 "{_. _}" match any set comprehension as expected.  Potential
  4872 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4873 constant "_idtdummy" in the binding position.
  4874 
  4875 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4876 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4877 for example "A -> B" => "Pi A (%_. B)".
  4878 
  4879 * Pure: 'class_deps' command visualizes the subclass relation, using
  4880 the graph browser tool.
  4881 
  4882 * Pure: 'print_theory' now suppresses certain internal declarations by
  4883 default; use '!' option for full details.
  4884 
  4885 
  4886 *** HOL ***
  4887 
  4888 * Method "metis" proves goals by applying the Metis general-purpose
  4889 resolution prover (see also http://gilith.com/software/metis/).
  4890 Examples are in the directory MetisExamples.  WARNING: the
  4891 Isabelle/HOL-Metis integration does not yet work properly with
  4892 multi-threading.
  4893   
  4894 * Command 'sledgehammer' invokes external automatic theorem provers as
  4895 background processes.  It generates calls to the "metis" method if
  4896 successful. These can be pasted into the proof.  Users do not have to
  4897 wait for the automatic provers to return.  WARNING: does not really
  4898 work with multi-threading.
  4899 
  4900 * New "auto_quickcheck" feature tests outermost goal statements for
  4901 potential counter-examples.  Controlled by ML references
  4902 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4903 5000 milliseconds).  Fails silently if statements is outside of
  4904 executable fragment, or any other codgenerator problem occurs.
  4905 
  4906 * New constant "undefined" with axiom "undefined x = undefined".
  4907 
  4908 * Added class "HOL.eq", allowing for code generation with polymorphic
  4909 equality.
  4910 
  4911 * Some renaming of class constants due to canonical name prefixing in
  4912 the new 'class' package:
  4913 
  4914     HOL.abs ~> HOL.abs_class.abs
  4915     HOL.divide ~> HOL.divide_class.divide
  4916     0 ~> HOL.zero_class.zero
  4917     1 ~> HOL.one_class.one
  4918     op + ~> HOL.plus_class.plus
  4919     op - ~> HOL.minus_class.minus
  4920     uminus ~> HOL.minus_class.uminus
  4921     op * ~> HOL.times_class.times
  4922     op < ~> HOL.ord_class.less
  4923     op <= > HOL.ord_class.less_eq
  4924     Nat.power ~> Power.power_class.power
  4925     Nat.size ~> Nat.size_class.size
  4926     Numeral.number_of ~> Numeral.number_class.number_of
  4927     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4928     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4929     Orderings.min ~> Orderings.ord_class.min
  4930     Orderings.max ~> Orderings.ord_class.max
  4931     Divides.op div ~> Divides.div_class.div
  4932     Divides.op mod ~> Divides.div_class.mod
  4933     Divides.op dvd ~> Divides.div_class.dvd
  4934 
  4935 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4936 
  4937 a) User-defined constants using any of the names "plus", "minus",
  4938 "times", "less" or "less_eq". The standard syntax translations for
  4939 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4940 names.
  4941 
  4942 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4943 INCOMPATIBILITY: use more specific names.
  4944 
  4945 c) Permutative equations (e.g. "a + b = b + a")
  4946 Since the change of names also changes the order of terms, permutative
  4947 rewrite rules may get applied in a different order. Experience shows
  4948 that this is rarely the case (only two adaptions in the whole Isabelle
  4949 distribution).  INCOMPATIBILITY: rewrite proofs
  4950 
  4951 d) ML code directly refering to constant names
  4952 This in general only affects hand-written proof tactics, simprocs and
  4953 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4954 Consider using @{const_name} antiquotation.
  4955 
  4956 * New class "default" with associated constant "default".
  4957 
  4958 * Function "sgn" is now overloaded and available on int, real, complex
  4959 (and other numeric types), using class "sgn".  Two possible defs of
  4960 sgn are given as equational assumptions in the classes sgn_if and
  4961 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4962 INCOMPATIBILITY.
  4963 
  4964 * Locale "partial_order" now unified with class "order" (cf. theory
  4965 Orderings), added parameter "less".  INCOMPATIBILITY.
  4966 
  4967 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4968 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4969 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4970 
  4971 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4972 changed order of proof goals in instance proofs.
  4973 
  4974 * The transitivity reasoner for partial and linear orders is set up
  4975 for classes "order" and "linorder".  Instances of the reasoner are available
  4976 in all contexts importing or interpreting the corresponding locales.
  4977 Method "order" invokes the reasoner separately; the reasoner
  4978 is also integrated with the Simplifier as a solver.  Diagnostic
  4979 command 'print_orders' shows the available instances of the reasoner
  4980 in the current context.
  4981 
  4982 * Localized monotonicity predicate in theory "Orderings"; integrated
  4983 lemmas max_of_mono and min_of_mono with this predicate.
  4984 INCOMPATIBILITY.
  4985 
  4986 * Formulation of theorem "dense" changed slightly due to integration
  4987 with new class dense_linear_order.
  4988 
  4989 * Uniform lattice theory development in HOL.
  4990 
  4991     constants "meet" and "join" now named "inf" and "sup"
  4992     constant "Meet" now named "Inf"
  4993 
  4994     classes "meet_semilorder" and "join_semilorder" now named
  4995       "lower_semilattice" and "upper_semilattice"
  4996     class "lorder" now named "lattice"
  4997     class "comp_lat" now named "complete_lattice"
  4998 
  4999     Instantiation of lattice classes allows explicit definitions
  5000     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  5001 
  5002   INCOMPATIBILITY.  Theorem renames:
  5003 
  5004     meet_left_le            ~> inf_le1
  5005     meet_right_le           ~> inf_le2
  5006     join_left_le            ~> sup_ge1
  5007     join_right_le           ~> sup_ge2
  5008     meet_join_le            ~> inf_sup_ord
  5009     le_meetI                ~> le_infI
  5010     join_leI                ~> le_supI
  5011     le_meet                 ~> le_inf_iff
  5012     le_join                 ~> ge_sup_conv
  5013     meet_idempotent         ~> inf_idem
  5014     join_idempotent         ~> sup_idem
  5015     meet_comm               ~> inf_commute
  5016     join_comm               ~> sup_commute
  5017     meet_leI1               ~> le_infI1
  5018     meet_leI2               ~> le_infI2
  5019     le_joinI1               ~> le_supI1
  5020     le_joinI2               ~> le_supI2
  5021     meet_assoc              ~> inf_assoc
  5022     join_assoc              ~> sup_assoc
  5023     meet_left_comm          ~> inf_left_commute
  5024     meet_left_idempotent    ~> inf_left_idem
  5025     join_left_comm          ~> sup_left_commute
  5026     join_left_idempotent    ~> sup_left_idem
  5027     meet_aci                ~> inf_aci
  5028     join_aci                ~> sup_aci
  5029     le_def_meet             ~> le_iff_inf
  5030     le_def_join             ~> le_iff_sup
  5031     join_absorp2            ~> sup_absorb2
  5032     join_absorp1            ~> sup_absorb1
  5033     meet_absorp1            ~> inf_absorb1
  5034     meet_absorp2            ~> inf_absorb2
  5035     meet_join_absorp        ~> inf_sup_absorb
  5036     join_meet_absorp        ~> sup_inf_absorb
  5037     distrib_join_le         ~> distrib_sup_le
  5038     distrib_meet_le         ~> distrib_inf_le
  5039 
  5040     add_meet_distrib_left   ~> add_inf_distrib_left
  5041     add_join_distrib_left   ~> add_sup_distrib_left
  5042     is_join_neg_meet        ~> is_join_neg_inf
  5043     is_meet_neg_join        ~> is_meet_neg_sup
  5044     add_meet_distrib_right  ~> add_inf_distrib_right
  5045     add_join_distrib_right  ~> add_sup_distrib_right
  5046     add_meet_join_distribs  ~> add_sup_inf_distribs
  5047     join_eq_neg_meet        ~> sup_eq_neg_inf
  5048     meet_eq_neg_join        ~> inf_eq_neg_sup
  5049     add_eq_meet_join        ~> add_eq_inf_sup
  5050     meet_0_imp_0            ~> inf_0_imp_0
  5051     join_0_imp_0            ~> sup_0_imp_0
  5052     meet_0_eq_0             ~> inf_0_eq_0
  5053     join_0_eq_0             ~> sup_0_eq_0
  5054     neg_meet_eq_join        ~> neg_inf_eq_sup
  5055     neg_join_eq_meet        ~> neg_sup_eq_inf
  5056     join_eq_if              ~> sup_eq_if
  5057 
  5058     mono_meet               ~> mono_inf
  5059     mono_join               ~> mono_sup
  5060     meet_bool_eq            ~> inf_bool_eq
  5061     join_bool_eq            ~> sup_bool_eq
  5062     meet_fun_eq             ~> inf_fun_eq
  5063     join_fun_eq             ~> sup_fun_eq
  5064     meet_set_eq             ~> inf_set_eq
  5065     join_set_eq             ~> sup_set_eq
  5066     meet1_iff               ~> inf1_iff
  5067     meet2_iff               ~> inf2_iff
  5068     meet1I                  ~> inf1I
  5069     meet2I                  ~> inf2I
  5070     meet1D1                 ~> inf1D1
  5071     meet2D1                 ~> inf2D1
  5072     meet1D2                 ~> inf1D2
  5073     meet2D2                 ~> inf2D2
  5074     meet1E                  ~> inf1E
  5075     meet2E                  ~> inf2E
  5076     join1_iff               ~> sup1_iff
  5077     join2_iff               ~> sup2_iff
  5078     join1I1                 ~> sup1I1
  5079     join2I1                 ~> sup2I1
  5080     join1I1                 ~> sup1I1
  5081     join2I2                 ~> sup1I2
  5082     join1CI                 ~> sup1CI
  5083     join2CI                 ~> sup2CI
  5084     join1E                  ~> sup1E
  5085     join2E                  ~> sup2E
  5086 
  5087     is_meet_Meet            ~> is_meet_Inf
  5088     Meet_bool_def           ~> Inf_bool_def
  5089     Meet_fun_def            ~> Inf_fun_def
  5090     Meet_greatest           ~> Inf_greatest
  5091     Meet_lower              ~> Inf_lower
  5092     Meet_set_def            ~> Inf_set_def
  5093 
  5094     Sup_def                 ~> Sup_Inf
  5095     Sup_bool_eq             ~> Sup_bool_def
  5096     Sup_fun_eq              ~> Sup_fun_def
  5097     Sup_set_eq              ~> Sup_set_def
  5098 
  5099     listsp_meetI            ~> listsp_infI
  5100     listsp_meet_eq          ~> listsp_inf_eq
  5101 
  5102     meet_min                ~> inf_min
  5103     join_max                ~> sup_max
  5104 
  5105 * Added syntactic class "size"; overloaded constant "size" now has
  5106 type "'a::size ==> bool"
  5107 
  5108 * Internal reorganisation of `size' of datatypes: size theorems
  5109 "foo.size" are no longer subsumed by "foo.simps" (but are still
  5110 simplification rules by default!); theorems "prod.size" now named
  5111 "*.size".
  5112 
  5113 * Class "div" now inherits from class "times" rather than "type".
  5114 INCOMPATIBILITY.
  5115 
  5116 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  5117 Linorder etc.  have disappeared; operations defined in terms of
  5118 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  5119 
  5120 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  5121 
  5122 * HOL-Word: New extensive library and type for generic, fixed size
  5123 machine words, with arithemtic, bit-wise, shifting and rotating
  5124 operations, reflection into int, nat, and bool lists, automation for
  5125 linear arithmetic (by automatic reflection into nat or int), including
  5126 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  5127 arithmetic type classes, supporting automatic simplification of
  5128 numerals on all operations.
  5129 
  5130 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  5131 
  5132 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  5133 
  5134 * Code generator library theories:
  5135   - Code_Integer represents HOL integers by big integer literals in target
  5136     languages.
  5137   - Code_Char represents HOL characters by character literals in target
  5138     languages.
  5139   - Code_Char_chr like Code_Char, but also offers treatment of character
  5140     codes; includes Code_Integer.
  5141   - Executable_Set allows to generate code for finite sets using lists.
  5142   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  5143     denominator).
  5144   - Executable_Real implements a subset of real numbers, namly those
  5145     representable by rational numbers.
  5146   - Efficient_Nat implements natural numbers by integers, which in general will
  5147     result in higher efficency; pattern matching with 0/Suc is eliminated;
  5148     includes Code_Integer.
  5149   - Code_Index provides an additional datatype index which is mapped to
  5150     target-language built-in integers.
  5151   - Code_Message provides an additional datatype message_string which is isomorphic to
  5152     strings; messages are mapped to target-language strings.
  5153 
  5154 * New package for inductive predicates
  5155 
  5156   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  5157 
  5158     inductive
  5159       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5160       for z_1 :: U_1 and ... and z_n :: U_m
  5161     where
  5162       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5163     | ...
  5164 
  5165   with full support for type-inference, rather than
  5166 
  5167     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5168 
  5169     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5170     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5171 
  5172     inductive "s z_1 ... z_m"
  5173     intros
  5174       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5175       ...
  5176 
  5177   For backward compatibility, there is a wrapper allowing inductive
  5178   sets to be defined with the new package via
  5179 
  5180     inductive_set
  5181       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5182       for z_1 :: U_1 and ... and z_n :: U_m
  5183     where
  5184       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5185     | ...
  5186 
  5187   or
  5188 
  5189     inductive_set
  5190       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5191       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5192       for z_1 :: U_1 and ... and z_n :: U_m
  5193     where
  5194       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5195     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5196     | ...
  5197 
  5198   if the additional syntax "p ..." is required.
  5199 
  5200   Numerous examples can be found in the subdirectories src/HOL/Auth,
  5201   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  5202 
  5203   INCOMPATIBILITIES:
  5204 
  5205   - Since declaration and definition of inductive sets or predicates
  5206     is no longer separated, abbreviations involving the newly
  5207     introduced sets or predicates must be specified together with the
  5208     introduction rules after the 'where' keyword (see above), rather
  5209     than before the actual inductive definition.
  5210 
  5211   - The variables in induction and elimination rules are now
  5212     quantified in the order of their occurrence in the introduction
  5213     rules, rather than in alphabetical order. Since this may break
  5214     some proofs, these proofs either have to be repaired, e.g. by
  5215     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  5216     statements of the form
  5217 
  5218       case (rule_i a_i_1 ... a_i_{k_i})
  5219 
  5220     or the old order of quantification has to be restored by explicitly adding
  5221     meta-level quantifiers in the introduction rules, i.e.
  5222 
  5223       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  5224 
  5225   - The format of the elimination rules is now
  5226 
  5227       p z_1 ... z_m x_1 ... x_n ==>
  5228         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5229         ==> ... ==> P
  5230 
  5231     for predicates and
  5232 
  5233       (x_1, ..., x_n) : s z_1 ... z_m ==>
  5234         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5235         ==> ... ==> P
  5236 
  5237     for sets rather than
  5238 
  5239       x : s z_1 ... z_m ==>
  5240         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  5241         ==> ... ==> P
  5242 
  5243     This may require terms in goals to be expanded to n-tuples
  5244     (e.g. using case_tac or simplification with the split_paired_all
  5245     rule) before the above elimination rule is applicable.
  5246 
  5247   - The elimination or case analysis rules for (mutually) inductive
  5248     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  5249     list of rules "p_1_..._p_k.elims" is no longer available.
  5250 
  5251 * New package "function"/"fun" for general recursive functions,
  5252 supporting mutual and nested recursion, definitions in local contexts,
  5253 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  5254 for small examples, and the separate tutorial on the function
  5255 package. The old recdef "package" is still available as before, but
  5256 users are encouraged to use the new package.
  5257 
  5258 * Method "lexicographic_order" automatically synthesizes termination
  5259 relations as lexicographic combinations of size measures. 
  5260 
  5261 * Case-expressions allow arbitrary constructor-patterns (including
  5262 "_") and take their order into account, like in functional
  5263 programming.  Internally, this is translated into nested
  5264 case-expressions; missing cases are added and mapped to the predefined
  5265 constant "undefined". In complicated cases printing may no longer show
  5266 the original input but the internal form. Lambda-abstractions allow
  5267 the same form of pattern matching: "% pat1 => e1 | ..." is an
  5268 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  5269 variable.
  5270 
  5271 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  5272 is an abbreviation for "of_nat :: nat => int". The simplification
  5273 rules for "of_nat" have been changed to work like "int" did
  5274 previously.  Potential INCOMPATIBILITY:
  5275   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  5276   - of_nat_diff and of_nat_mult are no longer default simp rules
  5277 
  5278 * Method "algebra" solves polynomial equations over (semi)rings using
  5279 Groebner bases. The (semi)ring structure is defined by locales and the
  5280 tool setup depends on that generic context. Installing the method for
  5281 a specific type involves instantiating the locale and possibly adding
  5282 declarations for computation on the coefficients.  The method is
  5283 already instantiated for natural numbers and for the axiomatic class
  5284 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  5285 CALCULEMUS 2007 for the general principles underlying this
  5286 architecture of context-aware proof-tools.
  5287 
  5288 * Method "ferrack" implements quantifier elimination over
  5289 special-purpose dense linear orders using locales (analogous to
  5290 "algebra"). The method is already installed for class
  5291 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  5292 rat, etc.
  5293 
  5294 * Former constant "List.op @" now named "List.append".  Use ML
  5295 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  5296 circumvent possible incompatibilities when working on ML level.
  5297 
  5298 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  5299 
  5300 * New function listsum :: 'a list => 'a for arbitrary monoids.
  5301 Special syntax: "SUM x <- xs. f x" (and latex variants)
  5302 
  5303 * New syntax for Haskell-like list comprehension (input only), eg.
  5304 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  5305 
  5306 * The special syntax for function "filter" has changed from [x :
  5307 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  5308 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  5309 
  5310 * [a..b] is now defined for arbitrary linear orders.  It used to be
  5311 defined on nat only, as an abbreviation for [a..<Suc b]
  5312 INCOMPATIBILITY.
  5313 
  5314 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  5315 
  5316 * New functions "sorted" and "sort" in src/HOL/List.thy.
  5317 
  5318 * New lemma collection field_simps (an extension of ring_simps) for
  5319 manipulating (in)equations involving division. Multiplies with all
  5320 denominators that can be proved to be non-zero (in equations) or
  5321 positive/negative (in inequations).
  5322 
  5323 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  5324 have been improved and renamed to ring_simps, group_simps and
  5325 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  5326 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  5327 
  5328 * Theory Library/Commutative_Ring: switched from recdef to function
  5329 package; constants add, mul, pow now curried.  Infix syntax for
  5330 algebraic operations.
  5331 
  5332 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  5333 INCOMPATIBILITY.
  5334 
  5335 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  5336 INCOMPATIBILITY.
  5337 
  5338 * HOL/records: generalised field-update to take a function on the
  5339 field rather than the new value: r(|A := x|) is translated to A_update
  5340 (K x) r The K-combinator that is internally used is called K_record.
  5341 INCOMPATIBILITY: Usage of the plain update functions has to be
  5342 adapted.
  5343  
  5344 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  5345 * x = 0, which are required for a semiring.  Richer structures do not
  5346 inherit from semiring_0 anymore, because this property is a theorem
  5347 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  5348 there is more to prove, but this is mostly trivial.
  5349 
  5350 * Class "recpower" is generalized to arbitrary monoids, not just
  5351 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  5352 commutativity or semiring properties additionally.
  5353 
  5354 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  5355 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  5356 better use 'abbreviation'.
  5357 
  5358 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  5359 
  5360 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  5361 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  5362 significant changes for setting up numeral syntax for types:
  5363   - New constants Numeral.pred and Numeral.succ instead
  5364       of former Numeral.bin_pred and Numeral.bin_succ.
  5365   - Use integer operations instead of bin_add, bin_mult and so on.
  5366   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  5367   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  5368 
  5369 See src/HOL/Integ/IntArith.thy for an example setup.
  5370 
  5371 * Command 'normal_form' computes the normal form of a term that may
  5372 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  5373 produces ``[b, c, a]'' (without proof).  This command is suitable for
  5374 heavy-duty computations because the functions are compiled to ML
  5375 first.  Correspondingly, a method "normalization" is provided.  See
  5376 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  5377 
  5378 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  5379 25 like -->); output depends on the "iff" print_mode, the default is
  5380 "A = B" (with priority 50).
  5381 
  5382 * Relations less (<) and less_eq (<=) are also available on type bool.
  5383 Modified syntax to disallow nesting without explicit parentheses,
  5384 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  5385 INCOMPATIBILITY.
  5386 
  5387 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  5388 
  5389 * Relation composition operator "op O" now has precedence 75 and binds
  5390 stronger than union and intersection. INCOMPATIBILITY.
  5391 
  5392 * The old set interval syntax "{m..n(}" (and relatives) has been
  5393 removed.  Use "{m..<n}" (and relatives) instead.
  5394 
  5395 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  5396 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  5397 ``declare [[simproc del: neq]]''.
  5398 
  5399 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  5400 True/False.
  5401 
  5402 * Theorem Cons_eq_map_conv no longer declared as "simp".
  5403 
  5404 * Theorem setsum_mult renamed to setsum_right_distrib.
  5405 
  5406 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  5407 ``rule'' method.
  5408 
  5409 * Reimplemented methods "sat" and "satx", with several improvements:
  5410 goals no longer need to be stated as "<prems> ==> False", equivalences
  5411 (i.e. "=" on type bool) are handled, variable names of the form
  5412 "lit_<n>" are no longer reserved, significant speedup.
  5413 
  5414 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  5415 zChaff is still supported as well.
  5416 
  5417 * 'inductive' and 'datatype': provide projections of mutual rules,
  5418 bundled as foo_bar.inducts;
  5419 
  5420 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  5421 Library.
  5422 
  5423 * Library: moved theory Accessible_Part to main HOL.
  5424 
  5425 * Library: added theory Coinductive_List of potentially infinite lists
  5426 as greatest fixed-point.
  5427 
  5428 * Library: added theory AssocList which implements (finite) maps as
  5429 association lists.
  5430 
  5431 * Method "evaluation" solves goals (i.e. a boolean expression)
  5432 efficiently by compiling it to ML.  The goal is "proved" (via an
  5433 oracle) if it evaluates to True.
  5434 
  5435 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  5436 also when invoked by the simplifier.  This results in the Simplifier
  5437 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  5438 Configuration option fast_arith_split_limit=0 recovers the old
  5439 behavior.
  5440 
  5441 * Support for hex (0x20) and binary (0b1001) numerals.
  5442 
  5443 * New method: reify eqs (t), where eqs are equations for an
  5444 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  5445 parameter, computes a term s::'b and a list xs::'a list and proves the
  5446 theorem I xs s = t. This is also known as reification or quoting. The
  5447 resulting theorem is applied to the subgoal to substitute t with I xs
  5448 s.  If t is omitted, the subgoal itself is reified.
  5449 
  5450 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  5451 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  5452 where f is supposed to be a computable function (in the sense of code
  5453 generattion). The method uses reify to compute s and xs as above then
  5454 applies corr_thm and uses normalization by evaluation to "prove" f s =
  5455 r and finally gets the theorem t = r, which is again applied to the
  5456 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  5457 
  5458 * Reflection: Automatic reification now handels binding, an example is
  5459 available in src/HOL/ex/ReflectionEx.thy
  5460 
  5461 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  5462 command 'statespace' that is similar to 'record', but introduces an
  5463 abstract specification based on the locale infrastructure instead of
  5464 HOL types.  This leads to extra flexibility in composing state spaces,
  5465 in particular multiple inheritance and renaming of components.
  5466 
  5467 
  5468 *** HOL-Complex ***
  5469 
  5470 * Hyperreal: Functions root and sqrt are now defined on negative real
  5471 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  5472 Nonnegativity side conditions have been removed from many lemmas, so
  5473 that more subgoals may now be solved by simplification; potential
  5474 INCOMPATIBILITY.
  5475 
  5476 * Real: new type classes formalize real normed vector spaces and
  5477 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  5478 and norm :: 'a => real.
  5479 
  5480 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  5481 reals into other types. The overloaded constant Reals :: 'a set is now
  5482 defined as range of_real; potential INCOMPATIBILITY.
  5483 
  5484 * Real: proper support for ML code generation, including 'quickcheck'.
  5485 Reals are implemented as arbitrary precision rationals.
  5486 
  5487 * Hyperreal: Several constants that previously worked only for the
  5488 reals have been generalized, so they now work over arbitrary vector
  5489 spaces. Type annotations may need to be added in some cases; potential
  5490 INCOMPATIBILITY.
  5491 
  5492   Infinitesimal  :: ('a::real_normed_vector) star set
  5493   HFinite        :: ('a::real_normed_vector) star set
  5494   HInfinite      :: ('a::real_normed_vector) star set
  5495   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5496   monad          :: ('a::real_normed_vector) star => 'a star set
  5497   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5498   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5499   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5500   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5501   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5502   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5503   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5504   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5505   sgn            :: 'a::real_normed_vector => 'a
  5506   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5507 
  5508 * Complex: Some complex-specific constants are now abbreviations for
  5509 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5510 hnorm.  Other constants have been entirely removed in favor of the
  5511 polymorphic versions (INCOMPATIBILITY):
  5512 
  5513   approx        <-- capprox
  5514   HFinite       <-- CFinite
  5515   HInfinite     <-- CInfinite
  5516   Infinitesimal <-- CInfinitesimal
  5517   monad         <-- cmonad
  5518   galaxy        <-- cgalaxy
  5519   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5520   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5521   (ns)deriv     <-- (ns)cderiv
  5522 
  5523 
  5524 *** HOL-Algebra ***
  5525 
  5526 * Formalisation of ideals and the quotient construction over rings.
  5527 
  5528 * Order and lattice theory no longer based on records.
  5529 INCOMPATIBILITY.
  5530 
  5531 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5532 greatest_closed.  INCOMPATIBILITY.
  5533 
  5534 * Method algebra is now set up via an attribute.  For examples see
  5535 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5536 of algebraic structures.
  5537 
  5538 * Renamed theory CRing to Ring.
  5539 
  5540 
  5541 *** HOL-Nominal ***
  5542 
  5543 * Substantial, yet incomplete support for nominal datatypes (binding
  5544 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5545 src/HOL/Nominal/Examples.  Prospective users should consult
  5546 http://isabelle.in.tum.de/nominal/
  5547 
  5548 
  5549 *** ML ***
  5550 
  5551 * ML basics: just one true type int, which coincides with IntInf.int
  5552 (even on SML/NJ).
  5553 
  5554 * ML within Isar: antiquotations allow to embed statically-checked
  5555 formal entities in the source, referring to the context available at
  5556 compile-time.  For example:
  5557 
  5558 ML {* @{sort "{zero,one}"} *}
  5559 ML {* @{typ "'a => 'b"} *}
  5560 ML {* @{term "%x. x"} *}
  5561 ML {* @{prop "x == y"} *}
  5562 ML {* @{ctyp "'a => 'b"} *}
  5563 ML {* @{cterm "%x. x"} *}
  5564 ML {* @{cprop "x == y"} *}
  5565 ML {* @{thm asm_rl} *}
  5566 ML {* @{thms asm_rl} *}
  5567 ML {* @{type_name c} *}
  5568 ML {* @{type_syntax c} *}
  5569 ML {* @{const_name c} *}
  5570 ML {* @{const_syntax c} *}
  5571 ML {* @{context} *}
  5572 ML {* @{theory} *}
  5573 ML {* @{theory Pure} *}
  5574 ML {* @{theory_ref} *}
  5575 ML {* @{theory_ref Pure} *}
  5576 ML {* @{simpset} *}
  5577 ML {* @{claset} *}
  5578 ML {* @{clasimpset} *}
  5579 
  5580 The same works for sources being ``used'' within an Isar context.
  5581 
  5582 * ML in Isar: improved error reporting; extra verbosity with
  5583 ML_Context.trace enabled.
  5584 
  5585 * Pure/General/table.ML: the join operations now works via exceptions
  5586 DUP/SAME instead of type option. This is simpler in simple cases, and
  5587 admits slightly more efficient complex applications.
  5588 
  5589 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5590 use Context.generic instead of just theory.
  5591 
  5592 * Pure: datatype Context.generic joins theory/Proof.context and
  5593 provides some facilities for code that works in either kind of
  5594 context, notably GenericDataFun for uniform theory and proof data.
  5595 
  5596 * Pure: simplified internal attribute type, which is now always
  5597 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5598 local (Proof.context) attributes have been discontinued, while
  5599 minimizing code duplication. Thm.rule_attribute and
  5600 Thm.declaration_attribute build canonical attributes; see also structure
  5601 Context for further operations on Context.generic, notably
  5602 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5603 declarations and definitions.
  5604 
  5605 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5606 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5607 init only required for impure data. INCOMPATIBILITY: empty really need
  5608 to be empty (no dependencies on theory content!)
  5609 
  5610 * Pure/kernel: consts certification ignores sort constraints given in
  5611 signature declarations. (This information is not relevant to the
  5612 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5613 potential INCOMPATIBILITY.
  5614 
  5615 * Pure: axiomatic type classes are now purely definitional, with
  5616 explicit proofs of class axioms and super class relations performed
  5617 internally. See Pure/axclass.ML for the main internal interfaces --
  5618 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5619 AxClass.axiomatize_class/classrel/arity supersede
  5620 Sign.add_classes/classrel/arities.
  5621 
  5622 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5623 global/local versions on theory vs. Proof.context have been
  5624 discontinued; Attrib.syntax and Method.syntax have been adapted
  5625 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5626 attributes, methods, etc.
  5627 
  5628 * Pure: several functions of signature "... -> theory -> theory * ..."
  5629 have been reoriented to "... -> theory -> ... * theory" in order to
  5630 allow natural usage in combination with the ||>, ||>>, |-> and
  5631 fold_map combinators.
  5632 
  5633 * Pure: official theorem names (closed derivations) and additional
  5634 comments (tags) are now strictly separate.  Name hints -- which are
  5635 maintained as tags -- may be attached any time without affecting the
  5636 derivation.
  5637 
  5638 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5639 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5640 achieve the old behaviour.
  5641 
  5642 * Pure: the "Goal" constant is now called "prop", supporting a
  5643 slightly more general idea of ``protecting'' meta-level rule
  5644 statements.
  5645 
  5646 * Pure: Logic.(un)varify only works in a global context, which is now
  5647 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5648 Logic.legacy_(un)varify as temporary workaround.
  5649 
  5650 * Pure: structure Name provides scalable operations for generating
  5651 internal variable names, notably Name.variants etc.  This replaces
  5652 some popular functions from term.ML:
  5653 
  5654   Term.variant		->  Name.variant
  5655   Term.variantlist	->  Name.variant_list
  5656   Term.invent_names	->  Name.invent_list
  5657 
  5658 Note that low-level renaming rarely occurs in new code -- operations
  5659 from structure Variable are used instead (see below).
  5660 
  5661 * Pure: structure Variable provides fundamental operations for proper
  5662 treatment of fixed/schematic variables in a context.  For example,
  5663 Variable.import introduces fixes for schematics of given facts and
  5664 Variable.export reverses the effect (up to renaming) -- this replaces
  5665 various freeze_thaw operations.
  5666 
  5667 * Pure: structure Goal provides simple interfaces for
  5668 init/conclude/finish and tactical prove operations (replacing former
  5669 Tactic.prove).  Goal.prove is the canonical way to prove results
  5670 within a given context; Goal.prove_global is a degraded version for
  5671 theory level goals, including a global Drule.standard.  Note that
  5672 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5673 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5674 in a locale context).
  5675 
  5676 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5677 and type checking (Syntax.check_term etc.), with common combinations
  5678 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5679 which are considered legacy and await removal.
  5680 
  5681 * Pure/Syntax: generic interfaces for type unchecking
  5682 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5683 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5684 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5685 available for convenience, but refer to the very same operations using
  5686 a mere theory instead of a full context.
  5687 
  5688 * Isar: simplified treatment of user-level errors, using exception
  5689 ERROR of string uniformly.  Function error now merely raises ERROR,
  5690 without any side effect on output channels.  The Isar toplevel takes
  5691 care of proper display of ERROR exceptions.  ML code may use plain
  5692 handle/can/try; cat_error may be used to concatenate errors like this:
  5693 
  5694   ... handle ERROR msg => cat_error msg "..."
  5695 
  5696 Toplevel ML code (run directly or through the Isar toplevel) may be
  5697 embedded into the Isar toplevel with exception display/debug like
  5698 this:
  5699 
  5700   Isar.toplevel (fn () => ...)
  5701 
  5702 INCOMPATIBILITY, removed special transform_error facilities, removed
  5703 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5704 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5705 -- use plain ERROR instead.
  5706 
  5707 * Isar: theory setup now has type (theory -> theory), instead of a
  5708 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5709 
  5710 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5711 ProofContext.debug/verbose flags.
  5712 
  5713 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5714 theory before entering a proof state.  Transactions now always see a
  5715 quasi-functional intermediate checkpoint, both in interactive and
  5716 batch mode.
  5717 
  5718 * Isar: simplified interfaces for outer syntax.  Renamed
  5719 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5720 OuterSyntax.add_parsers -- this functionality is now included in
  5721 OuterSyntax.command etc.  INCOMPATIBILITY.
  5722 
  5723 * Simplifier: the simpset of a running simplification process now
  5724 contains a proof context (cf. Simplifier.the_context), which is the
  5725 very context that the initial simpset has been retrieved from (by
  5726 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5727 (solver, looper etc.) may depend on arbitrary proof data.
  5728 
  5729 * Simplifier.inherit_context inherits the proof context (plus the
  5730 local bounds) of the current simplification process; any simproc
  5731 etc. that calls the Simplifier recursively should do this!  Removed
  5732 former Simplifier.inherit_bounds, which is already included here --
  5733 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5734 specify an explicit context using Simplifier.context/theory_context.
  5735 
  5736 * Simplifier/Classical Reasoner: more abstract interfaces
  5737 change_simpset/claset for modifying the simpset/claset reference of a
  5738 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5739 INCOMPATIBILITY.
  5740 
  5741 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5742 "Trueprop" etc.
  5743 
  5744 
  5745 *** System ***
  5746 
  5747 * settings: the default heap location within ISABELLE_HOME_USER now
  5748 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5749 Isabelle installations.
  5750 
  5751 * isabelle-process: option -S (secure mode) disables some critical
  5752 operations, notably runtime compilation and evaluation of ML source
  5753 code.
  5754 
  5755 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5756 
  5757 * Support for parallel execution, using native multicore support of
  5758 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5759 independent theories, according to the given theory header
  5760 specifications. The maximum number of worker threads is specified via
  5761 usedir option -M or the "max-threads" setting in Proof General. A
  5762 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5763 to 6 on a 8-core machine.  User-code needs to observe certain
  5764 guidelines for thread-safe programming, see appendix A in the Isar
  5765 Implementation manual.
  5766 
  5767 
  5768 
  5769 New in Isabelle2005 (October 2005)
  5770 ----------------------------------
  5771 
  5772 *** General ***
  5773 
  5774 * Theory headers: the new header syntax for Isar theories is
  5775 
  5776   theory <name>
  5777   imports <theory1> ... <theoryN>
  5778   uses <file1> ... <fileM>
  5779   begin
  5780 
  5781 where the 'uses' part is optional.  The previous syntax
  5782 
  5783   theory <name> = <theory1> + ... + <theoryN>:
  5784 
  5785 will disappear in the next release.  Use isatool fixheaders to convert
  5786 existing theory files.  Note that there is no change in ancient
  5787 non-Isar theories now, but these will disappear soon.
  5788 
  5789 * Theory loader: parent theories can now also be referred to via
  5790 relative and absolute paths.
  5791 
  5792 * Command 'find_theorems' searches for a list of criteria instead of a
  5793 list of constants. Known criteria are: intro, elim, dest, name:string,
  5794 simp:term, and any term. Criteria can be preceded by '-' to select
  5795 theorems that do not match. Intro, elim, dest select theorems that
  5796 match the current goal, name:s selects theorems whose fully qualified
  5797 name contain s, and simp:term selects all simplification rules whose
  5798 lhs match term.  Any other term is interpreted as pattern and selects
  5799 all theorems matching the pattern. Available in ProofGeneral under
  5800 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5801 
  5802   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5803 
  5804 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5805 matching the current goal as introduction rule and not having "HOL."
  5806 in their name (i.e. not being defined in theory HOL).
  5807 
  5808 * Command 'thms_containing' has been discontinued in favour of
  5809 'find_theorems'; INCOMPATIBILITY.
  5810 
  5811 * Communication with Proof General is now 8bit clean, which means that
  5812 Unicode text in UTF-8 encoding may be used within theory texts (both
  5813 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5814 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5815 
  5816   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5817   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5818 
  5819 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5820 Classical Reasoner.  Typical big applications run around 2 times
  5821 faster.
  5822 
  5823 
  5824 *** Document preparation ***
  5825 
  5826 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5827 of raw sources.  Only those symbols that do not require additional
  5828 LaTeX packages (depending on comments in isabellesym.sty) are
  5829 displayed properly, everything else is left verbatim.  isatool display
  5830 and isatool print are used as front ends (these are subject to the
  5831 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5832 
  5833 * Command tags control specific markup of certain regions of text,
  5834 notably folding and hiding.  Predefined tags include "theory" (for
  5835 theory begin and end), "proof" for proof commands, and "ML" for
  5836 commands involving ML code; the additional tags "visible" and
  5837 "invisible" are unused by default.  Users may give explicit tag
  5838 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5839 interpretation of tags is determined by the LaTeX job during document
  5840 preparation: see option -V of isatool usedir, or options -n and -t of
  5841 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5842 \isadroptag.
  5843 
  5844 Several document versions may be produced at the same time via isatool
  5845 usedir (the generated index.html will link all of them).  Typical
  5846 specifications include ''-V document=theory,proof,ML'' to present
  5847 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5848 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5849 these parts without any formal replacement text.  The Isabelle site
  5850 default settings produce ''document'' and ''outline'' versions as
  5851 specified above.
  5852 
  5853 * Several new antiquotations:
  5854 
  5855   @{term_type term} prints a term with its type annotated;
  5856 
  5857   @{typeof term} prints the type of a term;
  5858 
  5859   @{const const} is the same as @{term const}, but checks that the
  5860   argument is a known logical constant;
  5861 
  5862   @{term_style style term} and @{thm_style style thm} print a term or
  5863   theorem applying a "style" to it
  5864 
  5865   @{ML text}
  5866 
  5867 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5868 definitions, equations, inequations etc., 'concl' printing only the
  5869 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5870 to print the specified premise.  TermStyle.add_style provides an ML
  5871 interface for introducing further styles.  See also the "LaTeX Sugar"
  5872 document practical applications.  The ML antiquotation prints
  5873 type-checked ML expressions verbatim.
  5874 
  5875 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5876 and 'text' support optional locale specification '(in loc)', which
  5877 specifies the default context for interpreting antiquotations.  For
  5878 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5879 
  5880 * Option 'locale=NAME' of antiquotations specifies an alternative
  5881 context interpreting the subsequent argument.  For example: @{thm
  5882 [locale=lattice] inf_assoc}.
  5883 
  5884 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5885 a proof context.
  5886 
  5887 * Proper output of antiquotations for theory commands involving a
  5888 proof context (such as 'locale' or 'theorem (in loc) ...').
  5889 
  5890 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5891 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5892 
  5893 * isatool usedir: new option -C (default true) controls whether option
  5894 -D should include a copy of the original document directory; -C false
  5895 prevents unwanted effects such as copying of administrative CVS data.
  5896 
  5897 
  5898 *** Pure ***
  5899 
  5900 * Considerably improved version of 'constdefs' command.  Now performs
  5901 automatic type-inference of declared constants; additional support for
  5902 local structure declarations (cf. locales and HOL records), see also
  5903 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5904 sequential dependencies of definitions within a single 'constdefs'
  5905 section; moreover, the declared name needs to be an identifier.  If
  5906 all fails, consider to fall back on 'consts' and 'defs' separately.
  5907 
  5908 * Improved indexed syntax and implicit structures.  First of all,
  5909 indexed syntax provides a notational device for subscripted
  5910 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5911 expressions.  Secondly, in a local context with structure
  5912 declarations, number indexes \<^sub>n or the empty index (default
  5913 number 1) refer to a certain fixed variable implicitly; option
  5914 show_structs controls printing of implicit structures.  Typical
  5915 applications of these concepts involve record types and locales.
  5916 
  5917 * New command 'no_syntax' removes grammar declarations (and
  5918 translations) resulting from the given syntax specification, which is
  5919 interpreted in the same manner as for the 'syntax' command.
  5920 
  5921 * 'Advanced' translation functions (parse_translation etc.) may depend
  5922 on the signature of the theory context being presently used for
  5923 parsing/printing, see also isar-ref manual.
  5924 
  5925 * Improved 'oracle' command provides a type-safe interface to turn an
  5926 ML expression of type theory -> T -> term into a primitive rule of
  5927 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5928 is already included here); see also FOL/ex/IffExample.thy;
  5929 INCOMPATIBILITY.
  5930 
  5931 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5932 before); "cI" is no longer bound, use "c.intro" instead.
  5933 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5934 axclasses vs. locales.
  5935 
  5936 * Improved internal renaming of symbolic identifiers -- attach primes
  5937 instead of base 26 numbers.
  5938 
  5939 * New flag show_question_marks controls printing of leading question
  5940 marks in schematic variable names.
  5941 
  5942 * In schematic variable names, *any* symbol following \<^isub> or
  5943 \<^isup> is now treated as part of the base name.  For example, the
  5944 following works without printing of awkward ".0" indexes:
  5945 
  5946   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5947     by simp
  5948 
  5949 * Inner syntax includes (*(*nested*) comments*).
  5950 
  5951 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5952 annotations as "(00...)".
  5953 
  5954 * Clear separation of logical types and nonterminals, where the latter
  5955 may only occur in 'syntax' specifications or type abbreviations.
  5956 Before that distinction was only partially implemented via type class
  5957 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5958 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5959 exotic syntax specifications may require further adaption
  5960 (e.g. Cube/Cube.thy).
  5961 
  5962 * Removed obsolete type class "logic", use the top sort {} instead.
  5963 Note that non-logical types should be declared as 'nonterminals'
  5964 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5965 specifications.
  5966 
  5967 * Attributes 'induct' and 'cases': type or set names may now be
  5968 locally fixed variables as well.
  5969 
  5970 * Simplifier: can now control the depth to which conditional rewriting
  5971 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5972 Limit.
  5973 
  5974 * Simplifier: simplification procedures may now take the current
  5975 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5976 interface), which is very useful for calling the Simplifier
  5977 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5978 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5979 low-level mk_simproc no longer applies Logic.varify internally, to
  5980 allow for use in a context of fixed variables.
  5981 
  5982 * thin_tac now works even if the assumption being deleted contains !!
  5983 or ==>.  More generally, erule now works even if the major premise of
  5984 the elimination rule contains !! or ==>.
  5985 
  5986 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5987 
  5988 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5989 from Pure, which contains all common declarations already.  Both
  5990 theories are defined via plain Isabelle/Isar .thy files.
  5991 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5992 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5993 use isatool fixcpure to adapt your theory and ML sources.
  5994 
  5995 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5996 selections of theorems in named facts via index ranges.
  5997 
  5998 * 'print_theorems': in theory mode, really print the difference
  5999 wrt. the last state (works for interactive theory development only),
  6000 in proof mode print all local facts (cf. 'print_facts');
  6001 
  6002 * 'hide': option '(open)' hides only base names.
  6003 
  6004 * More efficient treatment of intermediate checkpoints in interactive
  6005 theory development.
  6006 
  6007 * Code generator is now invoked via code_module (incremental code
  6008 generation) and code_library (modular code generation, ML structures
  6009 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  6010 must be quoted when used as identifiers.
  6011 
  6012 * New 'value' command for reading, evaluating and printing terms using
  6013 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  6014 quoted when used as identifier.
  6015 
  6016 
  6017 *** Locales ***
  6018 
  6019 * New commands for the interpretation of locale expressions in
  6020 theories (1), locales (2) and proof contexts (3).  These generate
  6021 proof obligations from the expression specification.  After the
  6022 obligations have been discharged, theorems of the expression are added
  6023 to the theory, target locale or proof context.  The synopsis of the
  6024 commands is a follows:
  6025 
  6026   (1) interpretation expr inst
  6027   (2) interpretation target < expr
  6028   (3) interpret expr inst
  6029 
  6030 Interpretation in theories and proof contexts require a parameter
  6031 instantiation of terms from the current context.  This is applied to
  6032 specifications and theorems of the interpreted expression.
  6033 Interpretation in locales only permits parameter renaming through the
  6034 locale expression.  Interpretation is smart in that interpretations
  6035 that are active already do not occur in proof obligations, neither are
  6036 instantiated theorems stored in duplicate.  Use 'print_interps' to
  6037 inspect active interpretations of a particular locale.  For details,
  6038 see the Isar Reference manual.  Examples can be found in
  6039 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  6040 
  6041 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  6042 'interpret' instead.
  6043 
  6044 * New context element 'constrains' for adding type constraints to
  6045 parameters.
  6046 
  6047 * Context expressions: renaming of parameters with syntax
  6048 redeclaration.
  6049 
  6050 * Locale declaration: 'includes' disallowed.
  6051 
  6052 * Proper static binding of attribute syntax -- i.e. types / terms /
  6053 facts mentioned as arguments are always those of the locale definition
  6054 context, independently of the context of later invocations.  Moreover,
  6055 locale operations (renaming and type / term instantiation) are applied
  6056 to attribute arguments as expected.
  6057 
  6058 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  6059 actual attributes; rare situations may require Attrib.attribute to
  6060 embed those attributes into Attrib.src that lack concrete syntax.
  6061 Attribute implementations need to cooperate properly with the static
  6062 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  6063 Attrib.XXX_thm etc. already do the right thing without further
  6064 intervention.  Only unusual applications -- such as "where" or "of"
  6065 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  6066 on the context and the facts involved -- may have to assign parsed
  6067 values to argument tokens explicitly.
  6068 
  6069 * Changed parameter management in theorem generation for long goal
  6070 statements with 'includes'.  INCOMPATIBILITY: produces a different
  6071 theorem statement in rare situations.
  6072 
  6073 * Locale inspection command 'print_locale' omits notes elements.  Use
  6074 'print_locale!' to have them included in the output.
  6075 
  6076 
  6077 *** Provers ***
  6078 
  6079 * Provers/hypsubst.ML: improved version of the subst method, for
  6080 single-step rewriting: it now works in bound variable contexts. New is
  6081 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  6082 rewrite a different subterm than the original subst method, which is
  6083 still available as 'simplesubst'.
  6084 
  6085 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  6086 and quasi orders.
  6087 
  6088 * Provers/trancl.ML: new transitivity reasoner for transitive and
  6089 reflexive-transitive closure of relations.
  6090 
  6091 * Provers/blast.ML: new reference depth_limit to make blast's depth
  6092 limit (previously hard-coded with a value of 20) user-definable.
  6093 
  6094 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  6095 is peformed already.  Object-logics merely need to finish their
  6096 initial simpset configuration as before.  INCOMPATIBILITY.
  6097 
  6098 
  6099 *** HOL ***
  6100 
  6101 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  6102 
  6103   syntax (epsilon)
  6104     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  6105 
  6106 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  6107 and x-symbol; use option '-m epsilon' to get it actually printed.
  6108 Moreover, the mathematically important symbolic identifier \<epsilon>
  6109 becomes available as variable, constant etc.  INCOMPATIBILITY,
  6110 
  6111 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  6112 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  6113 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  6114 support corresponding Isar calculations.
  6115 
  6116 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  6117 instead of ":".
  6118 
  6119 * theory SetInterval: changed the syntax for open intervals:
  6120 
  6121   Old       New
  6122   {..n(}    {..<n}
  6123   {)n..}    {n<..}
  6124   {m..n(}   {m..<n}
  6125   {)m..n}   {m<..n}
  6126   {)m..n(}  {m<..<n}
  6127 
  6128 The old syntax is still supported but will disappear in the next
  6129 release.  For conversion use the following Emacs search and replace
  6130 patterns (these are not perfect but work quite well):
  6131 
  6132   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  6133   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  6134 
  6135 * Theory Commutative_Ring (in Library): method comm_ring for proving
  6136 equalities in commutative rings; method 'algebra' provides a generic
  6137 interface.
  6138 
  6139 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  6140 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  6141 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  6142 be a tuple pattern.
  6143 
  6144 Some new syntax forms are available:
  6145 
  6146   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  6147   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  6148   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  6149   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  6150 
  6151 The latter form "\<Sum>x < k. e" used to be based on a separate
  6152 function "Summation", which has been discontinued.
  6153 
  6154 * theory Finite_Set: in structured induction proofs, the insert case
  6155 is now 'case (insert x F)' instead of the old counterintuitive 'case
  6156 (insert F x)'.
  6157 
  6158 * The 'refute' command has been extended to support a much larger
  6159 fragment of HOL, including axiomatic type classes, constdefs and
  6160 typedefs, inductive datatypes and recursion.
  6161 
  6162 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  6163 Requires zChaff with proof generation to be installed.  See
  6164 HOL/ex/SAT_Examples.thy for examples.
  6165 
  6166 * Datatype induction via method 'induct' now preserves the name of the
  6167 induction variable. For example, when proving P(xs::'a list) by
  6168 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  6169 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  6170 in unstructured proof scripts.
  6171 
  6172 * Reworked implementation of records.  Improved scalability for
  6173 records with many fields, avoiding performance problems for type
  6174 inference. Records are no longer composed of nested field types, but
  6175 of nested extension types. Therefore the record type only grows linear
  6176 in the number of extensions and not in the number of fields.  The
  6177 top-level (users) view on records is preserved.  Potential
  6178 INCOMPATIBILITY only in strange cases, where the theory depends on the
  6179 old record representation. The type generated for a record is called
  6180 <record_name>_ext_type.
  6181 
  6182 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  6183 proofs triggered by a record definition or a simproc (if
  6184 quick_and_dirty is enabled).  Definitions of large records can take
  6185 quite long.
  6186 
  6187 New simproc record_upd_simproc for simplification of multiple record
  6188 updates enabled by default.  Moreover, trivial updates are also
  6189 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  6190 occasionally, since simplification is more powerful by default.
  6191 
  6192 * typedef: proper support for polymorphic sets, which contain extra
  6193 type-variables in the term.
  6194 
  6195 * Simplifier: automatically reasons about transitivity chains
  6196 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  6197 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  6198 old proofs break occasionally as simplification may now solve more
  6199 goals than previously.
  6200 
  6201 * Simplifier: converts x <= y into x = y if assumption y <= x is
  6202 present.  Works for all partial orders (class "order"), in particular
  6203 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  6204 just like y <= x.
  6205 
  6206 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  6207 bound variable or a constant then the let is unfolded.  Otherwise
  6208 first a is simplified to b, and then f b is simplified to g. If
  6209 possible we abstract b from g arriving at "let x = b in h x",
  6210 otherwise we unfold the let and arrive at g.  The simproc can be
  6211 enabled/disabled by the reference use_let_simproc.  Potential
  6212 INCOMPATIBILITY since simplification is more powerful by default.
  6213 
  6214 * Classical reasoning: the meson method now accepts theorems as arguments.
  6215 
  6216 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  6217 jobs to provide advice on the provability of subgoals.
  6218 
  6219 * Theory OrderedGroup and Ring_and_Field: various additions and
  6220 improvements to faciliate calculations involving equalities and
  6221 inequalities.
  6222 
  6223 The following theorems have been eliminated or modified
  6224 (INCOMPATIBILITY):
  6225 
  6226   abs_eq             now named abs_of_nonneg
  6227   abs_of_ge_0        now named abs_of_nonneg
  6228   abs_minus_eq       now named abs_of_nonpos
  6229   imp_abs_id         now named abs_of_nonneg
  6230   imp_abs_neg_id     now named abs_of_nonpos
  6231   mult_pos           now named mult_pos_pos
  6232   mult_pos_le        now named mult_nonneg_nonneg
  6233   mult_pos_neg_le    now named mult_nonneg_nonpos
  6234   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  6235   mult_neg           now named mult_neg_neg
  6236   mult_neg_le        now named mult_nonpos_nonpos
  6237 
  6238 * The following lemmas in Ring_and_Field have been added to the simplifier:
  6239      
  6240      zero_le_square
  6241      not_square_less_zero 
  6242 
  6243   The following lemmas have been deleted from Real/RealPow:
  6244   
  6245      realpow_zero_zero
  6246      realpow_two
  6247      realpow_less
  6248      zero_le_power
  6249      realpow_two_le
  6250      abs_realpow_two
  6251      realpow_two_abs     
  6252 
  6253 * Theory Parity: added rules for simplifying exponents.
  6254 
  6255 * Theory List:
  6256 
  6257 The following theorems have been eliminated or modified
  6258 (INCOMPATIBILITY):
  6259 
  6260   list_all_Nil       now named list_all.simps(1)
  6261   list_all_Cons      now named list_all.simps(2)
  6262   list_all_conv      now named list_all_iff
  6263   set_mem_eq         now named mem_iff
  6264 
  6265 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  6266 asymptotic "big O" calculations.  See the notes in BigO.thy.
  6267 
  6268 
  6269 *** HOL-Complex ***
  6270 
  6271 * Theory RealDef: better support for embedding natural numbers and
  6272 integers in the reals.
  6273 
  6274 The following theorems have been eliminated or modified
  6275 (INCOMPATIBILITY):
  6276 
  6277   exp_ge_add_one_self  now requires no hypotheses
  6278   real_of_int_add      reversed direction of equality (use [symmetric])
  6279   real_of_int_minus    reversed direction of equality (use [symmetric])
  6280   real_of_int_diff     reversed direction of equality (use [symmetric])
  6281   real_of_int_mult     reversed direction of equality (use [symmetric])
  6282 
  6283 * Theory RComplete: expanded support for floor and ceiling functions.
  6284 
  6285 * Theory Ln is new, with properties of the natural logarithm
  6286 
  6287 * Hyperreal: There is a new type constructor "star" for making
  6288 nonstandard types.  The old type names are now type synonyms:
  6289 
  6290   hypreal = real star
  6291   hypnat = nat star
  6292   hcomplex = complex star
  6293 
  6294 * Hyperreal: Many groups of similarly-defined constants have been
  6295 replaced by polymorphic versions (INCOMPATIBILITY):
  6296 
  6297   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  6298 
  6299   starset      <-- starsetNat, starsetC
  6300   *s*          <-- *sNat*, *sc*
  6301   starset_n    <-- starsetNat_n, starsetC_n
  6302   *sn*         <-- *sNatn*, *scn*
  6303   InternalSets <-- InternalNatSets, InternalCSets
  6304 
  6305   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  6306   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  6307   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  6308   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  6309   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  6310 
  6311 * Hyperreal: Many type-specific theorems have been removed in favor of
  6312 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  6313 
  6314   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  6315   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  6316   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  6317   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  6318   right_minus <-- hypreal_add_minus
  6319   left_minus <-- {hypreal,hcomplex}_add_minus_left
  6320   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  6321   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  6322   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  6323   mult_1_right <-- hcomplex_mult_one_right
  6324   mult_zero_left <-- hcomplex_mult_zero_left
  6325   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  6326   right_distrib <-- hypnat_add_mult_distrib2
  6327   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  6328   right_inverse <-- hypreal_mult_inverse
  6329   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  6330   order_refl <-- {hypreal,hypnat}_le_refl
  6331   order_trans <-- {hypreal,hypnat}_le_trans
  6332   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  6333   order_less_le <-- {hypreal,hypnat}_less_le
  6334   linorder_linear <-- {hypreal,hypnat}_le_linear
  6335   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  6336   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  6337   add_nonneg_nonneg <-- hypreal_le_add_order
  6338 
  6339 * Hyperreal: Separate theorems having to do with type-specific
  6340 versions of constants have been merged into theorems that apply to the
  6341 new polymorphic constants (INCOMPATIBILITY):
  6342 
  6343   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  6344   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  6345   STAR_Un <-- {STAR,NatStar,STARC}_Un
  6346   STAR_Int <-- {STAR,NatStar,STARC}_Int
  6347   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  6348   STAR_subset <-- {STAR,NatStar,STARC}_subset
  6349   STAR_mem <-- {STAR,NatStar,STARC}_mem
  6350   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  6351   STAR_diff <-- {STAR,STARC}_diff
  6352   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  6353     STARC_hcomplex_of_complex}_image_subset
  6354   starset_n_Un <-- starset{Nat,C}_n_Un
  6355   starset_n_Int <-- starset{Nat,C}_n_Int
  6356   starset_n_Compl <-- starset{Nat,C}_n_Compl
  6357   starset_n_diff <-- starset{Nat,C}_n_diff
  6358   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  6359   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  6360   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  6361   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  6362   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  6363   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  6364   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  6365   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  6366   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  6367   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  6368   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  6369   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  6370   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  6371   starfun_diff <-- starfun{C,RC,CR}_diff
  6372   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  6373   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  6374   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  6375   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  6376   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  6377   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  6378   starfun_Id <-- starfunC_Id
  6379   starfun_approx <-- starfun{Nat,CR}_approx
  6380   starfun_capprox <-- starfun{C,RC}_capprox
  6381   starfun_abs <-- starfunNat_rabs
  6382   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  6383   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  6384   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  6385   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  6386   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  6387   starfun_add_approx <-- starfunCR_add_approx
  6388   starfun_inverse_inverse <-- starfunC_inverse_inverse
  6389   starfun_divide <-- starfun{C,CR,RC}_divide
  6390   starfun_n <-- starfun{Nat,C}_n
  6391   starfun_n_mult <-- starfun{Nat,C}_n_mult
  6392   starfun_n_add <-- starfun{Nat,C}_n_add
  6393   starfun_n_add_minus <-- starfunNat_n_add_minus
  6394   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  6395   starfun_n_minus <-- starfun{Nat,C}_n_minus
  6396   starfun_n_eq <-- starfun{Nat,C}_n_eq
  6397 
  6398   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  6399   star_n_minus <-- {hypreal,hcomplex}_minus
  6400   star_n_diff <-- {hypreal,hcomplex}_diff
  6401   star_n_mult <-- {hypreal,hcomplex}_mult
  6402   star_n_inverse <-- {hypreal,hcomplex}_inverse
  6403   star_n_le <-- {hypreal,hypnat}_le
  6404   star_n_less <-- {hypreal,hypnat}_less
  6405   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  6406   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  6407   star_n_abs <-- hypreal_hrabs
  6408   star_n_divide <-- hcomplex_divide
  6409 
  6410   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  6411   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  6412   star_of_diff <-- hypreal_of_real_diff
  6413   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  6414   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  6415   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  6416   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  6417   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  6418   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  6419   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  6420   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  6421   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  6422   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  6423   star_of_number_of <-- {hypreal,hcomplex}_number_of
  6424   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  6425   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  6426   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  6427   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  6428   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  6429   star_of_power <-- hypreal_of_real_power
  6430   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  6431 
  6432 * Hyperreal: new method "transfer" that implements the transfer
  6433 principle of nonstandard analysis. With a subgoal that mentions
  6434 nonstandard types like "'a star", the command "apply transfer"
  6435 replaces it with an equivalent one that mentions only standard types.
  6436 To be successful, all free variables must have standard types; non-
  6437 standard variables must have explicit universal quantifiers.
  6438 
  6439 * Hyperreal: A theory of Taylor series.
  6440 
  6441 
  6442 *** HOLCF ***
  6443 
  6444 * Discontinued special version of 'constdefs' (which used to support
  6445 continuous functions) in favor of the general Pure one with full
  6446 type-inference.
  6447 
  6448 * New simplification procedure for solving continuity conditions; it
  6449 is much faster on terms with many nested lambda abstractions (cubic
  6450 instead of exponential time).
  6451 
  6452 * New syntax for domain package: selector names are now optional.
  6453 Parentheses should be omitted unless argument is lazy, for example:
  6454 
  6455   domain 'a stream = cons "'a" (lazy "'a stream")
  6456 
  6457 * New command 'fixrec' for defining recursive functions with pattern
  6458 matching; defining multiple functions with mutual recursion is also
  6459 supported.  Patterns may include the constants cpair, spair, up, sinl,
  6460 sinr, or any data constructor defined by the domain package. The given
  6461 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  6462 syntax and examples.
  6463 
  6464 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  6465 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  6466 but the proof obligation additionally includes an admissibility
  6467 requirement. The packages generate instances of class cpo or pcpo,
  6468 with continuity and strictness theorems for Rep and Abs.
  6469 
  6470 * HOLCF: Many theorems have been renamed according to a more standard naming
  6471 scheme (INCOMPATIBILITY):
  6472 
  6473   foo_inject:  "foo$x = foo$y ==> x = y"
  6474   foo_eq:      "(foo$x = foo$y) = (x = y)"
  6475   foo_less:    "(foo$x << foo$y) = (x << y)"
  6476   foo_strict:  "foo$UU = UU"
  6477   foo_defined: "... ==> foo$x ~= UU"
  6478   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  6479 
  6480 
  6481 *** ZF ***
  6482 
  6483 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  6484 including the First Isomorphism Theorem (on quotienting by the kernel
  6485 of a homomorphism).
  6486 
  6487 * ZF/Simplifier: install second copy of type solver that actually
  6488 makes use of TC rules declared to Isar proof contexts (or locales);
  6489 the old version is still required for ML proof scripts.
  6490 
  6491 
  6492 *** Cube ***
  6493 
  6494 * Converted to Isar theory format; use locales instead of axiomatic
  6495 theories.
  6496 
  6497 
  6498 *** ML ***
  6499 
  6500 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6501 for ||>, ||>>, |>>,
  6502 
  6503 * Pure/library.ML no longer defines its own option datatype, but uses
  6504 that of the SML basis, which has constructors NONE and SOME instead of
  6505 None and Some, as well as exception Option.Option instead of OPTION.
  6506 The functions the, if_none, is_some, is_none have been adapted
  6507 accordingly, while Option.map replaces apsome.
  6508 
  6509 * Pure/library.ML: the exception LIST has been given up in favour of
  6510 the standard exceptions Empty and Subscript, as well as
  6511 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6512 superceded by the standard hd and tl functions etc.
  6513 
  6514 A number of basic list functions are no longer exported to the ML
  6515 toplevel, as they are variants of predefined functions.  The following
  6516 suggests how one can translate existing code:
  6517 
  6518     rev_append xs ys = List.revAppend (xs, ys)
  6519     nth_elem (i, xs) = List.nth (xs, i)
  6520     last_elem xs = List.last xs
  6521     flat xss = List.concat xss
  6522     seq fs = List.app fs
  6523     partition P xs = List.partition P xs
  6524     mapfilter f xs = List.mapPartial f xs
  6525 
  6526 * Pure/library.ML: several combinators for linear functional
  6527 transformations, notably reverse application and composition:
  6528 
  6529   x |> f                f #> g
  6530   (x, y) |-> f          f #-> g
  6531 
  6532 * Pure/library.ML: introduced/changed precedence of infix operators:
  6533 
  6534   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6535   infix 2 ?;
  6536   infix 3 o oo ooo oooo;
  6537   infix 4 ~~ upto downto;
  6538 
  6539 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6540 infix operators.
  6541 
  6542 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6543 fold_map support linear functional transformations and nesting.  For
  6544 example:
  6545 
  6546   fold f [x1, ..., xN] y =
  6547     y |> f x1 |> ... |> f xN
  6548 
  6549   (fold o fold) f [xs1, ..., xsN] y =
  6550     y |> fold f xs1 |> ... |> fold f xsN
  6551 
  6552   fold f [x1, ..., xN] =
  6553     f x1 #> ... #> f xN
  6554 
  6555   (fold o fold) f [xs1, ..., xsN] =
  6556     fold f xs1 #> ... #> fold f xsN
  6557 
  6558 * Pure/library.ML: the following selectors on type 'a option are
  6559 available:
  6560 
  6561   the:               'a option -> 'a  (*partial*)
  6562   these:             'a option -> 'a  where 'a = 'b list
  6563   the_default: 'a -> 'a option -> 'a
  6564   the_list:          'a option -> 'a list
  6565 
  6566 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6567 basic operations for association lists, following natural argument
  6568 order; moreover the explicit equality predicate passed here avoids
  6569 potentially expensive polymorphic runtime equality checks.
  6570 The old functions may be expressed as follows:
  6571 
  6572   assoc = uncurry (AList.lookup (op =))
  6573   assocs = these oo AList.lookup (op =)
  6574   overwrite = uncurry (AList.update (op =)) o swap
  6575 
  6576 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6577 
  6578   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6579   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6580 
  6581 replacing make_keylist and keyfilter (occassionally used)
  6582 Naive rewrites:
  6583 
  6584   make_keylist = AList.make
  6585   keyfilter = AList.find (op =)
  6586 
  6587 * eq_fst and eq_snd now take explicit equality parameter, thus
  6588   avoiding eqtypes. Naive rewrites:
  6589 
  6590     eq_fst = eq_fst (op =)
  6591     eq_snd = eq_snd (op =)
  6592 
  6593 * Removed deprecated apl and apr (rarely used).
  6594   Naive rewrites:
  6595 
  6596     apl (n, op) =>>= curry op n
  6597     apr (op, m) =>>= fn n => op (n, m)
  6598 
  6599 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6600 provides a reasonably efficient light-weight implementation of sets as
  6601 lists.
  6602 
  6603 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6604 few new operations; existing lookup and update are now curried to
  6605 follow natural argument order (for use with fold etc.);
  6606 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6607 
  6608 * Pure/General: output via the Isabelle channels of
  6609 writeln/warning/error etc. is now passed through Output.output, with a
  6610 hook for arbitrary transformations depending on the print_mode
  6611 (cf. Output.add_mode -- the first active mode that provides a output
  6612 function wins).  Already formatted output may be embedded into further
  6613 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6614 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6615 accommodate easy composition of diagnostic messages etc.  Programmers
  6616 rarely need to care about Output.output or Output.raw at all, with
  6617 some notable exceptions: Output.output is required when bypassing the
  6618 standard channels (writeln etc.), or in token translations to produce
  6619 properly formatted results; Output.raw is required when capturing
  6620 already output material that will eventually be presented to the user
  6621 a second time.  For the default print mode, both Output.output and
  6622 Output.raw have no effect.
  6623 
  6624 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6625 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6626 cumulative results are displayed at the end of a batch session.
  6627 
  6628 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6629 replaced by File.platform_path and File.shell_path (with appropriate
  6630 hooks).  This provides a clean interface for unusual systems where the
  6631 internal and external process view of file names are different.
  6632 
  6633 * Pure: more efficient orders for basic syntactic entities: added
  6634 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6635 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6636 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6637 orders now -- potential INCOMPATIBILITY for code that depends on a
  6638 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6639 Library.sort_strings on result).
  6640 
  6641 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6642 fold_types traverse types/terms from left to right, observing natural
  6643 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6644 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6645 
  6646 * Pure: name spaces have been refined, with significant changes of the
  6647 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6648 to extern(_table).  The plain name entry path is superceded by a
  6649 general 'naming' context, which also includes the 'policy' to produce
  6650 a fully qualified name and external accesses of a fully qualified
  6651 name; NameSpace.extend is superceded by context dependent
  6652 Sign.declare_name.  Several theory and proof context operations modify
  6653 the naming context.  Especially note Theory.restore_naming and
  6654 ProofContext.restore_naming to get back to a sane state; note that
  6655 Theory.add_path is no longer sufficient to recover from
  6656 Theory.absolute_path in particular.
  6657 
  6658 * Pure: new flags short_names (default false) and unique_names
  6659 (default true) for controlling output of qualified names.  If
  6660 short_names is set, names are printed unqualified.  If unique_names is
  6661 reset, the name prefix is reduced to the minimum required to achieve
  6662 the original result when interning again, even if there is an overlap
  6663 with earlier declarations.
  6664 
  6665 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6666 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6667 (useful for printing error messages).  INCOMPATIBILITY.
  6668 
  6669 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6670 Theory.theory are now identified, referring to the universal
  6671 Context.theory (see Pure/context.ML).  Actual signature and theory
  6672 content is managed as theory data.  The old code and interfaces were
  6673 spread over many files and structures; the new arrangement introduces
  6674 considerable INCOMPATIBILITY to gain more clarity:
  6675 
  6676   Context -- theory management operations (name, identity, inclusion,
  6677     parents, ancestors, merge, etc.), plus generic theory data;
  6678 
  6679   Sign -- logical signature and syntax operations (declaring consts,
  6680     types, etc.), plus certify/read for common entities;
  6681 
  6682   Theory -- logical theory operations (stating axioms, definitions,
  6683     oracles), plus a copy of logical signature operations (consts,
  6684     types, etc.); also a few basic management operations (Theory.copy,
  6685     Theory.merge, etc.)
  6686 
  6687 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6688 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6689 for convenience -- they merely return the theory.
  6690 
  6691 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6692 
  6693 * Pure: the Isar proof context type is already defined early in Pure
  6694 as Context.proof (note that ProofContext.context and Proof.context are
  6695 aliases, where the latter is the preferred name).  This enables other
  6696 Isabelle components to refer to that type even before Isar is present.
  6697 
  6698 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6699 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6700 any of these kinds.  For example, Sign.intern typeK is now
  6701 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6702 Theory.hide_types.  Also note that former
  6703 Theory.hide_classes/types/consts are now
  6704 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6705 internalize their arguments!  INCOMPATIBILITY.
  6706 
  6707 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6708 datatype thmref (with constructors Name and NameSelection) instead of
  6709 plain string -- INCOMPATIBILITY;
  6710 
  6711 * Pure: cases produced by proof methods specify options, where NONE
  6712 means to remove case bindings -- INCOMPATIBILITY in
  6713 (RAW_)METHOD_CASES.
  6714 
  6715 * Pure: the following operations retrieve axioms or theorems from a
  6716 theory node or theory hierarchy, respectively:
  6717 
  6718   Theory.axioms_of: theory -> (string * term) list
  6719   Theory.all_axioms_of: theory -> (string * term) list
  6720   PureThy.thms_of: theory -> (string * thm) list
  6721   PureThy.all_thms_of: theory -> (string * thm) list
  6722 
  6723 * Pure: print_tac now outputs the goal through the trace channel.
  6724 
  6725 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6726 Reference Toplevel.debug (default false) controls detailed printing
  6727 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6728 controls execution profiling -- set to 1 for time and 2 for space
  6729 (both increase the runtime).
  6730 
  6731 * Isar session: The initial use of ROOT.ML is now always timed,
  6732 i.e. the log will show the actual process times, in contrast to the
  6733 elapsed wall-clock time that the outer shell wrapper produces.
  6734 
  6735 * Simplifier: improved handling of bound variables (nameless
  6736 representation, avoid allocating new strings).  Simprocs that invoke
  6737 the Simplifier recursively should use Simplifier.inherit_bounds to
  6738 avoid local name clashes.  Failure to do so produces warnings
  6739 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6740 for further details.
  6741 
  6742 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6743 bindings for all theorems stored within a given theory; this may help
  6744 in porting non-Isar theories to Isar ones, while keeping ML proof
  6745 scripts for the time being.
  6746 
  6747 * ML operator HTML.with_charset specifies the charset begin used for
  6748 generated HTML files.  For example:
  6749 
  6750   HTML.with_charset "utf-8" use_thy "Hebrew";
  6751   HTML.with_charset "utf-8" use_thy "Chinese";
  6752 
  6753 
  6754 *** System ***
  6755 
  6756 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6757 isabelle, isatool etc.).
  6758 
  6759 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6760 isatool doc, isatool mkdir, display_drafts etc.).
  6761 
  6762 * isatool usedir: option -f allows specification of the ML file to be
  6763 used by Isabelle; default is ROOT.ML.
  6764 
  6765 * New isatool version outputs the version identifier of the Isabelle
  6766 distribution being used.
  6767 
  6768 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6769 (containing Boolean satisfiability problems) into Isabelle/HOL
  6770 theories.
  6771 
  6772 
  6773 
  6774 New in Isabelle2004 (April 2004)
  6775 --------------------------------
  6776 
  6777 *** General ***
  6778 
  6779 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6780   Replaces linorder.ML.
  6781 
  6782 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6783   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6784   (\<a>...\<z>), are now considered normal letters, and can therefore
  6785   be used anywhere where an ASCII letter (a...zA...Z) has until
  6786   now. COMPATIBILITY: This obviously changes the parsing of some
  6787   terms, especially where a symbol has been used as a binder, say
  6788   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6789   as an identifier.  Fix it by inserting a space around former
  6790   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6791   existing theory and ML files.
  6792 
  6793 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6794 
  6795 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6796   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6797   a normal (but invisible) letter. For multiple letter subscripts repeat
  6798   \<^isub> like this: x\<^isub>1\<^isub>2.
  6799 
  6800 * Pure: There are now sub-/superscripts that can span more than one
  6801   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6802   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6803   superscript. The new control characters are not identifier parts.
  6804 
  6805 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6806   content of "..." to the latex file instead of \isacntrl... . The "..."
  6807   may consist of any printable characters excluding the end bracket >.
  6808 
  6809 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6810   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6811   declare constants "final", which prevents their being given a definition
  6812   later.  It is useful for constants whose behaviour is fixed axiomatically
  6813   rather than definitionally, such as the meta-logic connectives.
  6814 
  6815 * Pure: 'instance' now handles general arities with general sorts
  6816   (i.e. intersections of classes),
  6817 
  6818 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6819   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6820   It can be changed to alter the colors/layout of generated pages.
  6821 
  6822 
  6823 *** Isar ***
  6824 
  6825 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6826   cut_tac, subgoal_tac and thin_tac:
  6827   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6828     locales are no longer forced to write Isar proof scripts.
  6829     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6830     emulations.
  6831   - INCOMPATIBILITY: names of variables to be instantiated may no
  6832     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6833     This is consistent with the instantiation attribute "where".
  6834 
  6835 * Attributes "where" and "of":
  6836   - Now take type variables of instantiated theorem into account when reading
  6837     the instantiation string.  This fixes a bug that caused instantiated
  6838     theorems to have too special types in some circumstances.
  6839   - "where" permits explicit instantiations of type variables.
  6840 
  6841 * Calculation commands "moreover" and "also" no longer interfere with
  6842   current facts ("this"), admitting arbitrary combinations with "then"
  6843   and derived forms.
  6844 
  6845 * Locales:
  6846   - Goal statements involving the context element "includes" no longer
  6847     generate theorems with internal delta predicates (those ending on
  6848     "_axioms") in the premise.
  6849     Resolve particular premise with <locale>.intro to obtain old form.
  6850   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6851     specification and "includes" elements in goal statement.
  6852   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6853     [intro?] and [elim?] (respectively) by default.
  6854   - Experimental command for instantiation of locales in proof contexts:
  6855         instantiate <label>[<attrs>]: <loc>
  6856     Instantiates locale <loc> and adds all its theorems to the current context
  6857     taking into account their attributes.  Label and attrs are optional
  6858     modifiers, like in theorem declarations.  If present, names of
  6859     instantiated theorems are qualified with <label>, and the attributes
  6860     <attrs> are applied after any attributes these theorems might have already.
  6861       If the locale has assumptions, a chained fact of the form
  6862     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6863     are derived.  The command does not support old-style locales declared
  6864     with "locale (open)".
  6865       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6866 
  6867 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6868   (Isar) contexts.
  6869 
  6870 
  6871 *** HOL ***
  6872 
  6873 * Proof import: new image HOL4 contains the imported library from
  6874   the HOL4 system with about 2500 theorems. It is imported by
  6875   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6876   can be used like any other Isabelle image.  See
  6877   HOL/Import/HOL/README for more information.
  6878 
  6879 * Simplifier:
  6880   - Much improved handling of linear and partial orders.
  6881     Reasoners for linear and partial orders are set up for type classes
  6882     "linorder" and "order" respectively, and are added to the default simpset
  6883     as solvers.  This means that the simplifier can build transitivity chains
  6884     to solve goals from the assumptions.
  6885   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6886     of blast or auto after simplification become unnecessary because the goal
  6887     is solved by simplification already.
  6888 
  6889 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6890     all proved in axiomatic type classes for semirings, rings and fields.
  6891 
  6892 * Numerics:
  6893   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6894     now formalized using the Ring_and_Field theory mentioned above.
  6895   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6896     than before, because now they are set up once in a generic manner.
  6897   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6898     Look for the general versions in Ring_and_Field (and Power if they concern
  6899     exponentiation).
  6900 
  6901 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6902 
  6903 * Records:
  6904   - Record types are now by default printed with their type abbreviation
  6905     instead of the list of all field types. This can be configured via
  6906     the reference "print_record_type_abbr".
  6907   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6908     (not enabled by default).
  6909   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6910     EX x. x = sel r to True (not enabled by default).
  6911   - Tactic "record_split_simp_tac" to split and simplify records added.
  6912 
  6913 * 'specification' command added, allowing for definition by
  6914   specification.  There is also an 'ax_specification' command that
  6915   introduces the new constants axiomatically.
  6916 
  6917 * arith(_tac) is now able to generate counterexamples for reals as well.
  6918 
  6919 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6920 
  6921 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6922   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6923 
  6924 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6925   matrix theory to linear programming.
  6926 
  6927 * Unions and Intersections:
  6928   The latex output syntax of UN and INT has been changed
  6929   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6930   i.e. the index formulae has become a subscript.
  6931   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6932 
  6933 * Unions and Intersections over Intervals:
  6934   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6935   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6936   like in normal math, and corresponding versions for < and for intersection.
  6937 
  6938 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6939   lexicographic dictonary ordering has been added as "lexord".
  6940 
  6941 * ML: the legacy theory structures Int and List have been removed. They had
  6942   conflicted with ML Basis Library structures having the same names.
  6943 
  6944 * 'refute' command added to search for (finite) countermodels.  Only works
  6945   for a fragment of HOL.  The installation of an external SAT solver is
  6946   highly recommended.  See "HOL/Refute.thy" for details.
  6947 
  6948 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6949   formulae under an assignment of free variables to random values.
  6950   In contrast to 'refute', it can deal with inductive datatypes,
  6951   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6952   for examples.
  6953 
  6954 
  6955 *** HOLCF ***
  6956 
  6957 * Streams now come with concatenation and are part of the HOLCF image
  6958 
  6959 
  6960 
  6961 New in Isabelle2003 (May 2003)
  6962 ------------------------------
  6963 
  6964 *** General ***
  6965 
  6966 * Provers/simplifier:
  6967 
  6968   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6969     Assumptions are now subject to complete mutual simplification,
  6970     not just from left to right. The simplifier now preserves
  6971     the order of assumptions.
  6972 
  6973     Potential INCOMPATIBILITY:
  6974 
  6975     -- simp sometimes diverges where the old version did
  6976        not, e.g. invoking simp on the goal
  6977 
  6978         [| P (f x); y = x; f x = f y |] ==> Q
  6979 
  6980        now gives rise to the infinite reduction sequence
  6981 
  6982         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6983 
  6984        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6985        kind of problem.
  6986 
  6987     -- Tactics combining classical reasoner and simplification (such as auto)
  6988        are also affected by this change, because many of them rely on
  6989        simp. They may sometimes diverge as well or yield a different numbers
  6990        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6991        in case of problems. Sometimes subsequent calls to the classical
  6992        reasoner will fail because a preceeding call to the simplifier too
  6993        eagerly simplified the goal, e.g. deleted redundant premises.
  6994 
  6995   - The simplifier trace now shows the names of the applied rewrite rules
  6996 
  6997   - You can limit the number of recursive invocations of the simplifier
  6998     during conditional rewriting (where the simplifie tries to solve the
  6999     conditions before applying the rewrite rule):
  7000     ML "simp_depth_limit := n"
  7001     where n is an integer. Thus you can force termination where previously
  7002     the simplifier would diverge.
  7003 
  7004   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  7005 
  7006   - No longer aborts on failed congruence proof.  Instead, the
  7007     congruence is ignored.
  7008 
  7009 * Pure: New generic framework for extracting programs from constructive
  7010   proofs. See HOL/Extraction.thy for an example instantiation, as well
  7011   as HOL/Extraction for some case studies.
  7012 
  7013 * Pure: The main goal of the proof state is no longer shown by default, only
  7014 the subgoals. This behaviour is controlled by a new flag.
  7015    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  7016 (ML: Proof.show_main_goal).
  7017 
  7018 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  7019 rules whose conclusion matches subgoal 1:
  7020       PG menu: Isabelle/Isar -> Show me -> matching rules
  7021 The rules are ordered by how closely they match the subgoal.
  7022 In particular, rules that solve a subgoal outright are displayed first
  7023 (or rather last, the way they are printed).
  7024 (ML: ProofGeneral.print_intros())
  7025 
  7026 * Pure: New flag trace_unify_fail causes unification to print
  7027 diagnostic information (PG: in trace buffer) when it fails. This is
  7028 useful for figuring out why single step proofs like rule, erule or
  7029 assumption failed.
  7030 
  7031 * Pure: Locale specifications now produce predicate definitions
  7032 according to the body of text (covering assumptions modulo local
  7033 definitions); predicate "loc_axioms" covers newly introduced text,
  7034 while "loc" is cumulative wrt. all included locale expressions; the
  7035 latter view is presented only on export into the global theory
  7036 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  7037 on the old view without predicates;
  7038 
  7039 * Pure: predefined locales "var" and "struct" are useful for sharing
  7040 parameters (as in CASL, for example); just specify something like
  7041 ``var x + var y + struct M'' as import;
  7042 
  7043 * Pure: improved thms_containing: proper indexing of facts instead of
  7044 raw theorems; check validity of results wrt. current name space;
  7045 include local facts of proof configuration (also covers active
  7046 locales), cover fixed variables in index; may use "_" in term
  7047 specification; an optional limit for the number of printed facts may
  7048 be given (the default is 40);
  7049 
  7050 * Pure: disallow duplicate fact bindings within new-style theory files
  7051 (batch-mode only);
  7052 
  7053 * Provers: improved induct method: assumptions introduced by case
  7054 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  7055 the goal statement); "foo" still refers to all facts collectively;
  7056 
  7057 * Provers: the function blast.overloaded has been removed: all constants
  7058 are regarded as potentially overloaded, which improves robustness in exchange
  7059 for slight decrease in efficiency;
  7060 
  7061 * Provers/linorder: New generic prover for transitivity reasoning over
  7062 linear orders.  Note: this prover is not efficient!
  7063 
  7064 * Isar: preview of problems to finish 'show' now produce an error
  7065 rather than just a warning (in interactive mode);
  7066 
  7067 
  7068 *** HOL ***
  7069 
  7070 * arith(_tac)
  7071 
  7072  - Produces a counter example if it cannot prove a goal.
  7073    Note that the counter example may be spurious if the goal is not a formula
  7074    of quantifier-free linear arithmetic.
  7075    In ProofGeneral the counter example appears in the trace buffer.
  7076 
  7077  - Knows about div k and mod k where k is a numeral of type nat or int.
  7078 
  7079  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  7080    linear arithmetic fails. This takes account of quantifiers and divisibility.
  7081    Presburger arithmetic can also be called explicitly via presburger(_tac).
  7082 
  7083 * simp's arithmetic capabilities have been enhanced a bit: it now
  7084 takes ~= in premises into account (by performing a case split);
  7085 
  7086 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  7087 are distributed over a sum of terms;
  7088 
  7089 * New tactic "trans_tac" and method "trans" instantiate
  7090 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  7091 "<=", "<" and "=").
  7092 
  7093 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  7094 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  7095 
  7096 * 'typedef' command has new option "open" to suppress the set
  7097 definition;
  7098 
  7099 * functions Min and Max on finite sets have been introduced (theory
  7100 Finite_Set);
  7101 
  7102 * attribute [symmetric] now works for relations as well; it turns
  7103 (x,y) : R^-1 into (y,x) : R, and vice versa;
  7104 
  7105 * induct over a !!-quantified statement (say !!x1..xn):
  7106   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  7107 
  7108 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  7109 %x. None. Warning: empty_def now refers to the previously hidden definition
  7110 of the empty set.
  7111 
  7112 * Algebra: formalization of classical algebra.  Intended as base for
  7113 any algebraic development in Isabelle.  Currently covers group theory
  7114 (up to Sylow's theorem) and ring theory (Universal Property of
  7115 Univariate Polynomials).  Contributions welcome;
  7116 
  7117 * GroupTheory: deleted, since its material has been moved to Algebra;
  7118 
  7119 * Complex: new directory of the complex numbers with numeric constants,
  7120 nonstandard complex numbers, and some complex analysis, standard and
  7121 nonstandard (Jacques Fleuriot);
  7122 
  7123 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  7124 
  7125 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  7126 Fleuriot);
  7127 
  7128 * Real/HahnBanach: updated and adapted to locales;
  7129 
  7130 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  7131 Gray and Kramer);
  7132 
  7133 * UNITY: added the Meier-Sanders theory of progress sets;
  7134 
  7135 * MicroJava: bytecode verifier and lightweight bytecode verifier
  7136 as abstract algorithms, instantiated to the JVM;
  7137 
  7138 * Bali: Java source language formalization. Type system, operational
  7139 semantics, axiomatic semantics. Supported language features:
  7140 classes, interfaces, objects,virtual methods, static methods,
  7141 static/instance fields, arrays, access modifiers, definite
  7142 assignment, exceptions.
  7143 
  7144 
  7145 *** ZF ***
  7146 
  7147 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  7148 universe, etc.);
  7149 
  7150 * Main ZF: virtually all theories converted to new-style format;
  7151 
  7152 
  7153 *** ML ***
  7154 
  7155 * Pure: Tactic.prove provides sane interface for internal proofs;
  7156 omits the infamous "standard" operation, so this is more appropriate
  7157 than prove_goalw_cterm in many situations (e.g. in simprocs);
  7158 
  7159 * Pure: improved error reporting of simprocs;
  7160 
  7161 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  7162 up simprocs;
  7163 
  7164 
  7165 *** Document preparation ***
  7166 
  7167 * uses \par instead of \\ for line breaks in theory text. This may
  7168 shift some page breaks in large documents. To get the old behaviour
  7169 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  7170 
  7171 * minimized dependencies of isabelle.sty and isabellesym.sty on
  7172 other packages
  7173 
  7174 * \<euro> now needs package babel/greek instead of marvosym (which
  7175 broke \Rightarrow)
  7176 
  7177 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  7178 textcomp package)
  7179 
  7180 
  7181 
  7182 New in Isabelle2002 (March 2002)
  7183 --------------------------------
  7184 
  7185 *** Document preparation ***
  7186 
  7187 * greatly simplified document preparation setup, including more
  7188 graceful interpretation of isatool usedir -i/-d/-D options, and more
  7189 instructive isatool mkdir; users should basically be able to get
  7190 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  7191 users may run a separate document processing stage manually like this:
  7192 "isatool usedir -D output HOL Test && isatool document Test/output";
  7193 
  7194 * theory dependency graph may now be incorporated into documents;
  7195 isatool usedir -g true will produce session_graph.eps/.pdf for use
  7196 with \includegraphics of LaTeX;
  7197 
  7198 * proper spacing of consecutive markup elements, especially text
  7199 blocks after section headings;
  7200 
  7201 * support bold style (for single symbols only), input syntax is like
  7202 this: "\<^bold>\<alpha>" or "\<^bold>A";
  7203 
  7204 * \<bullet> is now output as bold \cdot by default, which looks much
  7205 better in printed text;
  7206 
  7207 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  7208 note that these symbols are currently unavailable in Proof General /
  7209 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  7210 
  7211 * isatool latex no longer depends on changed TEXINPUTS, instead
  7212 isatool document copies the Isabelle style files to the target
  7213 location;
  7214 
  7215 
  7216 *** Isar ***
  7217 
  7218 * Pure/Provers: improved proof by cases and induction;
  7219   - 'case' command admits impromptu naming of parameters (such as
  7220     "case (Suc n)");
  7221   - 'induct' method divinates rule instantiation from the inductive
  7222     claim; no longer requires excessive ?P bindings for proper
  7223     instantiation of cases;
  7224   - 'induct' method properly enumerates all possibilities of set/type
  7225     rules; as a consequence facts may be also passed through *type*
  7226     rules without further ado;
  7227   - 'induct' method now derives symbolic cases from the *rulified*
  7228     rule (before it used to rulify cases stemming from the internal
  7229     atomized version); this means that the context of a non-atomic
  7230     statement becomes is included in the hypothesis, avoiding the
  7231     slightly cumbersome show "PROP ?case" form;
  7232   - 'induct' may now use elim-style induction rules without chaining
  7233     facts, using ``missing'' premises from the goal state; this allows
  7234     rules stemming from inductive sets to be applied in unstructured
  7235     scripts, while still benefitting from proper handling of non-atomic
  7236     statements; NB: major inductive premises need to be put first, all
  7237     the rest of the goal is passed through the induction;
  7238   - 'induct' proper support for mutual induction involving non-atomic
  7239     rule statements (uses the new concept of simultaneous goals, see
  7240     below);
  7241   - append all possible rule selections, but only use the first
  7242     success (no backtracking);
  7243   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  7244   - undeclared rule case names default to numbers 1, 2, 3, ...;
  7245   - added 'print_induct_rules' (covered by help item in recent Proof
  7246     General versions);
  7247   - moved induct/cases attributes to Pure, methods to Provers;
  7248   - generic method setup instantiated for FOL and HOL;
  7249 
  7250 * Pure: support multiple simultaneous goal statements, for example
  7251 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  7252 meta-level mechanism, this acts as if several individual goals had
  7253 been stated separately; in particular common proof methods need to be
  7254 repeated in order to cover all claims; note that a single elimination
  7255 step is *not* sufficient to establish the two conjunctions, so this
  7256 fails:
  7257 
  7258   assume "A & B" then have A and B ..   (*".." fails*)
  7259 
  7260 better use "obtain" in situations as above; alternative refer to
  7261 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  7262 
  7263 * Pure: proper integration with ``locales''; unlike the original
  7264 version by Florian Kammller, Isar locales package high-level proof
  7265 contexts rather than raw logical ones (e.g. we admit to include
  7266 attributes everywhere); operations on locales include merge and
  7267 rename; support for implicit arguments (``structures''); simultaneous
  7268 type-inference over imports and text; see also HOL/ex/Locales.thy for
  7269 some examples;
  7270 
  7271 * Pure: the following commands have been ``localized'', supporting a
  7272 target locale specification "(in name)": 'lemma', 'theorem',
  7273 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  7274 stored both within the locale and at the theory level (exported and
  7275 qualified by the locale name);
  7276 
  7277 * Pure: theory goals may now be specified in ``long'' form, with
  7278 ad-hoc contexts consisting of arbitrary locale elements. for example
  7279 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  7280 definitions may be given, too); the result is a meta-level rule with
  7281 the context elements being discharged in the obvious way;
  7282 
  7283 * Pure: new proof command 'using' allows to augment currently used
  7284 facts after a goal statement ('using' is syntactically analogous to
  7285 'apply', but acts on the goal's facts only); this allows chained facts
  7286 to be separated into parts given before and after a claim, as in
  7287 ``from a and b have C using d and e <proof>'';
  7288 
  7289 * Pure: renamed "antecedent" case to "rule_context";
  7290 
  7291 * Pure: new 'judgment' command records explicit information about the
  7292 object-logic embedding (used by several tools internally); no longer
  7293 use hard-wired "Trueprop";
  7294 
  7295 * Pure: added 'corollary' command;
  7296 
  7297 * Pure: fixed 'token_translation' command;
  7298 
  7299 * Pure: removed obsolete 'exported' attribute;
  7300 
  7301 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  7302 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  7303 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  7304 
  7305 * Pure: method 'atomize' presents local goal premises as object-level
  7306 statements (atomic meta-level propositions); setup controlled via
  7307 rewrite rules declarations of 'atomize' attribute; example
  7308 application: 'induct' method with proper rule statements in improper
  7309 proof *scripts*;
  7310 
  7311 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  7312 now consider the syntactic context of assumptions, giving a better
  7313 chance to get type-inference of the arguments right (this is
  7314 especially important for locales);
  7315 
  7316 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  7317 mode;
  7318 
  7319 * Pure/obtain: the formal conclusion "thesis", being marked as
  7320 ``internal'', may no longer be reference directly in the text;
  7321 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  7322 situations;
  7323 
  7324 * Pure: generic 'sym' attribute which declares a rule both as pure
  7325 'elim?' and for the 'symmetric' operation;
  7326 
  7327 * Pure: marginal comments ``--'' may now occur just anywhere in the
  7328 text; the fixed correlation with particular command syntax has been
  7329 discontinued;
  7330 
  7331 * Pure: new method 'rules' is particularly well-suited for proof
  7332 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  7333 but often produces more compact proof terms with less detours;
  7334 
  7335 * Pure/Provers/classical: simplified integration with pure rule
  7336 attributes and methods; the classical "intro?/elim?/dest?"
  7337 declarations coincide with the pure ones; the "rule" method no longer
  7338 includes classically swapped intros; "intro" and "elim" methods no
  7339 longer pick rules from the context; also got rid of ML declarations
  7340 AddXIs/AddXEs/AddXDs; all of this has some potential for
  7341 INCOMPATIBILITY;
  7342 
  7343 * Provers/classical: attribute 'swapped' produces classical inversions
  7344 of introduction rules;
  7345 
  7346 * Provers/simplifier: 'simplified' attribute may refer to explicit
  7347 rules instead of full simplifier context; 'iff' attribute handles
  7348 conditional rules;
  7349 
  7350 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  7351 
  7352 * HOL: 'recdef' now fails on unfinished automated proofs, use
  7353 "(permissive)" option to recover old behavior;
  7354 
  7355 * HOL: 'inductive' no longer features separate (collective) attributes
  7356 for 'intros' (was found too confusing);
  7357 
  7358 * HOL: properly declared induction rules less_induct and
  7359 wf_induct_rule;
  7360 
  7361 
  7362 *** HOL ***
  7363 
  7364 * HOL: moved over to sane numeral syntax; the new policy is as
  7365 follows:
  7366 
  7367   - 0 and 1 are polymorphic constants, which are defined on any
  7368   numeric type (nat, int, real etc.);
  7369 
  7370   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  7371   binary representation internally;
  7372 
  7373   - type nat has special constructor Suc, and generally prefers Suc 0
  7374   over 1::nat and Suc (Suc 0) over 2::nat;
  7375 
  7376 This change may cause significant problems of INCOMPATIBILITY; here
  7377 are some hints on converting existing sources:
  7378 
  7379   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  7380   entities, so expressions involving "-" (unary or binary minus) need
  7381   to be spaced properly;
  7382 
  7383   - existing occurrences of "1" may need to be constraint "1::nat" or
  7384   even replaced by Suc 0; similar for old "2";
  7385 
  7386   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  7387 
  7388   - remove all special provisions on numerals in proofs;
  7389 
  7390 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  7391 representation (depends on bin_arith_simps in the default context);
  7392 
  7393 * HOL: symbolic syntax for x^2 (numeral 2);
  7394 
  7395 * HOL: the class of all HOL types is now called "type" rather than
  7396 "term"; INCOMPATIBILITY, need to adapt references to this type class
  7397 in axclass/classes, instance/arities, and (usually rare) occurrences
  7398 in typings (of consts etc.); internally the class is called
  7399 "HOL.type", ML programs should refer to HOLogic.typeS;
  7400 
  7401 * HOL/record package improvements:
  7402   - new derived operations "fields" to build a partial record section,
  7403     "extend" to promote a fixed record to a record scheme, and
  7404     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  7405     declared as simp by default;
  7406   - shared operations ("more", "fields", etc.) now need to be always
  7407     qualified) --- potential INCOMPATIBILITY;
  7408   - removed "make_scheme" operations (use "make" with "extend") --
  7409     INCOMPATIBILITY;
  7410   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  7411   - provides cases/induct rules for use with corresponding Isar
  7412     methods (for concrete records, record schemes, concrete more
  7413     parts, and schematic more parts -- in that order);
  7414   - internal definitions directly based on a light-weight abstract
  7415     theory of product types over typedef rather than datatype;
  7416 
  7417 * HOL: generic code generator for generating executable ML code from
  7418 specifications; specific support for HOL constructs such as inductive
  7419 datatypes and sets, as well as recursive functions; can be invoked
  7420 via 'generate_code' theory section;
  7421 
  7422 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  7423 
  7424 * HOL: consolidated and renamed several theories.  In particular:
  7425         Ord.thy has been absorbed into HOL.thy
  7426         String.thy has been absorbed into List.thy
  7427 
  7428 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  7429 (beware of argument permutation!);
  7430 
  7431 * HOL: linorder_less_split superseded by linorder_cases;
  7432 
  7433 * HOL/List: "nodups" renamed to "distinct";
  7434 
  7435 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  7436 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  7437   - Ex_def has changed, now need to use some_eq_ex
  7438 
  7439 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  7440 in this (rare) case use:
  7441 
  7442   delSWrapper "split_all_tac"
  7443   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  7444 
  7445 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  7446 MAY FAIL;
  7447 
  7448 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  7449 Isabelle's type classes, ^ on functions and relations has too general
  7450 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  7451 necessary to attach explicit type constraints;
  7452 
  7453 * HOL/Relation: the prefix name of the infix "O" has been changed from
  7454 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  7455 renamed accordingly (eg "compI" -> "rel_compI").
  7456 
  7457 * HOL: syntax translations now work properly with numerals and records
  7458 expressions;
  7459 
  7460 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  7461 of "lam" -- INCOMPATIBILITY;
  7462 
  7463 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  7464 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  7465 renamed "Product_Type.unit";
  7466 
  7467 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  7468 
  7469 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  7470 the "cases" method);
  7471 
  7472 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  7473 Florian Kammller);
  7474 
  7475 * HOL/IMP: updated and converted to new-style theory format; several
  7476 parts turned into readable document, with proper Isar proof texts and
  7477 some explanations (by Gerwin Klein);
  7478 
  7479 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  7480 
  7481 * HOL-Hyperreal is now a logic image;
  7482 
  7483 
  7484 *** HOLCF ***
  7485 
  7486 * Isar: consts/constdefs supports mixfix syntax for continuous
  7487 operations;
  7488 
  7489 * Isar: domain package adapted to new-style theory format, e.g. see
  7490 HOLCF/ex/Dnat.thy;
  7491 
  7492 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7493 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7494 lift.induct_tac, always use UU instead of Undef;
  7495 
  7496 * HOLCF/IMP: updated and converted to new-style theory;
  7497 
  7498 
  7499 *** ZF ***
  7500 
  7501 * Isar: proper integration of logic-specific tools and packages,
  7502 including theory commands '(co)inductive', '(co)datatype',
  7503 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7504 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7505 
  7506 * theory Main no longer includes AC; for the Axiom of Choice, base
  7507 your theory on Main_ZFC;
  7508 
  7509 * the integer library now covers quotients and remainders, with many
  7510 laws relating division to addition, multiplication, etc.;
  7511 
  7512 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7513 typeless version of the formalism;
  7514 
  7515 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7516 format;
  7517 
  7518 * ZF/Induct: new directory for examples of inductive definitions,
  7519 including theory Multiset for multiset orderings; converted to
  7520 new-style theory format;
  7521 
  7522 * ZF: many new theorems about lists, ordinals, etc.;
  7523 
  7524 
  7525 *** General ***
  7526 
  7527 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7528 variable proof controls level of detail: 0 = no proofs (only oracle
  7529 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7530 also ref manual for further ML interfaces;
  7531 
  7532 * Pure/axclass: removed obsolete ML interface
  7533 goal_subclass/goal_arity;
  7534 
  7535 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7536 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7537 separate tokens, so expressions involving minus need to be spaced
  7538 properly;
  7539 
  7540 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7541 rather than "infixl" or "infixr";
  7542 
  7543 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7544 sort constraint specifications in type inference; e.g. "x::_::foo"
  7545 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7546 type variable);
  7547 
  7548 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7549 control output of nested => (types); the default behavior is
  7550 "type_brackets";
  7551 
  7552 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7553 tokens into AST constants;
  7554 
  7555 * Pure/syntax: prefer later declarations of translations and print
  7556 translation functions; potential INCOMPATIBILITY: need to reverse
  7557 multiple declarations for same syntax element constant;
  7558 
  7559 * Pure/show_hyps reset by default (in accordance to existing Isar
  7560 practice);
  7561 
  7562 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7563 addSafter;
  7564 
  7565 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7566 as well;
  7567 
  7568 * system: tested support for MacOS X; should be able to get Isabelle +
  7569 Proof General to work in a plain Terminal after installing Poly/ML
  7570 (e.g. from the Isabelle distribution area) and GNU bash alone
  7571 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7572 support requires further installations, e.g. from
  7573 http://fink.sourceforge.net/);
  7574 
  7575 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7576 
  7577 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7578 of 40 MB), cf. ML_OPTIONS;
  7579 
  7580 * system: Proof General keywords specification is now part of the
  7581 Isabelle distribution (see etc/isar-keywords.el);
  7582 
  7583 * system: support for persistent Proof General sessions (refrain from
  7584 outdating all loaded theories on startup); user may create writable
  7585 logic images like this: ``isabelle -q HOL Test'';
  7586 
  7587 * system: smart selection of Isabelle process versus Isabelle
  7588 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7589 run both "isabelle" and "Isabelle" even if file names are badly
  7590 damaged (executable inspects the case of the first letter of its own
  7591 name); added separate "isabelle-process" and "isabelle-interface";
  7592 
  7593 * system: refrain from any attempt at filtering input streams; no
  7594 longer support ``8bit'' encoding of old isabelle font, instead proper
  7595 iso-latin characters may now be used; the related isatools
  7596 "symbolinput" and "nonascii" have disappeared as well;
  7597 
  7598 * system: removed old "xterm" interface (the print modes "xterm" and
  7599 "xterm_color" are still available for direct use in a suitable
  7600 terminal);
  7601 
  7602 
  7603 
  7604 New in Isabelle99-2 (February 2001)
  7605 -----------------------------------
  7606 
  7607 *** Overview of INCOMPATIBILITIES ***
  7608 
  7609 * HOL: please note that theories in the Library and elsewhere often use the
  7610 new-style (Isar) format; to refer to their theorems in an ML script you must
  7611 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  7612 
  7613 * HOL: inductive package no longer splits induction rule aggressively,
  7614 but only as far as specified by the introductions given; the old
  7615 format may be recovered via ML function complete_split_rule or attribute
  7616 'split_rule (complete)';
  7617 
  7618 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  7619 gfp_Tarski to gfp_unfold;
  7620 
  7621 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  7622 
  7623 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  7624 relation); infix "^^" has been renamed "``"; infix "``" has been
  7625 renamed "`"; "univalent" has been renamed "single_valued";
  7626 
  7627 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  7628 operation;
  7629 
  7630 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  7631 
  7632 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  7633 
  7634 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  7635 consequence, it is no longer monotonic wrt. the local goal context
  7636 (which is now passed through the inductive cases);
  7637 
  7638 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  7639 \<gg> to \<ggreater>;
  7640 
  7641 
  7642 *** Document preparation ***
  7643 
  7644 * \isabellestyle{NAME} selects version of Isabelle output (currently
  7645 available: are "it" for near math-mode best-style output, "sl" for
  7646 slanted text style, and "tt" for plain type-writer; if no
  7647 \isabellestyle command is given, output is according to slanted
  7648 type-writer);
  7649 
  7650 * support sub/super scripts (for single symbols only), input syntax is
  7651 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  7652 
  7653 * some more standard symbols; see Appendix A of the system manual for
  7654 the complete list of symbols defined in isabellesym.sty;
  7655 
  7656 * improved isabelle style files; more abstract symbol implementation
  7657 (should now use \isamath{...} and \isatext{...} in custom symbol
  7658 definitions);
  7659 
  7660 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  7661 state; Note that presentation of goal states does not conform to
  7662 actual human-readable proof documents.  Please do not include goal
  7663 states into document output unless you really know what you are doing!
  7664 
  7665 * proper indentation of antiquoted output with proportional LaTeX
  7666 fonts;
  7667 
  7668 * no_document ML operator temporarily disables LaTeX document
  7669 generation;
  7670 
  7671 * isatool unsymbolize tunes sources for plain ASCII communication;
  7672 
  7673 
  7674 *** Isar ***
  7675 
  7676 * Pure: Isar now suffers initial goal statements to contain unbound
  7677 schematic variables (this does not conform to actual readable proof
  7678 documents, due to unpredictable outcome and non-compositional proof
  7679 checking); users who know what they are doing may use schematic goals
  7680 for Prolog-style synthesis of proven results;
  7681 
  7682 * Pure: assumption method (an implicit finishing) now handles actual
  7683 rules as well;
  7684 
  7685 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  7686 initial goal, declare "that" only as Pure intro (only for single
  7687 steps); the "that" rule assumption may now be involved in implicit
  7688 finishing, thus ".." becomes a feasible for trivial obtains;
  7689 
  7690 * Pure: default proof step now includes 'intro_classes'; thus trivial
  7691 instance proofs may be performed by "..";
  7692 
  7693 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  7694 statements as well;
  7695 
  7696 * Pure: more robust selection of calculational rules;
  7697 
  7698 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  7699 rule (as well as the assumption rule);
  7700 
  7701 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  7702 lemmas, using the graph browser tool;
  7703 
  7704 * Pure: predict failure of "show" in interactive mode;
  7705 
  7706 * Pure: 'thms_containing' now takes actual terms as arguments;
  7707 
  7708 * HOL: improved method 'induct' --- now handles non-atomic goals
  7709 (potential INCOMPATIBILITY); tuned error handling;
  7710 
  7711 * HOL: cases and induct rules now provide explicit hints about the
  7712 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  7713 any remaining facts are inserted into the goal verbatim;
  7714 
  7715 * HOL: local contexts (aka cases) may now contain term bindings as
  7716 well; the 'cases' and 'induct' methods new provide a ?case binding for
  7717 the result to be shown in each case;
  7718 
  7719 * HOL: added 'recdef_tc' command;
  7720 
  7721 * isatool convert assists in eliminating legacy ML scripts;
  7722 
  7723 
  7724 *** HOL ***
  7725 
  7726 * HOL/Library: a collection of generic theories to be used together
  7727 with main HOL; the theory loader path already includes this directory
  7728 by default; the following existing theories have been moved here:
  7729 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  7730 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  7731 
  7732 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  7733 modelling and verification task performed in Isabelle/HOL +
  7734 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  7735 
  7736 * HOL/Algebra: special summation operator SUM no longer exists, it has
  7737 been replaced by setsum; infix 'assoc' now has priority 50 (like
  7738 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  7739 'domain', this makes the theory consistent with mathematical
  7740 literature;
  7741 
  7742 * HOL basics: added overloaded operations "inverse" and "divide"
  7743 (infix "/"), syntax for generic "abs" operation, generic summation
  7744 operator \<Sum>;
  7745 
  7746 * HOL/typedef: simplified package, provide more useful rules (see also
  7747 HOL/subset.thy);
  7748 
  7749 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  7750 now expressed as a proper nested rule (old-style tactic scripts may
  7751 require atomize_strip_tac to cope with non-atomic premises);
  7752 
  7753 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  7754 to "split_conv" (old name still available for compatibility);
  7755 
  7756 * HOL: improved concrete syntax for strings (e.g. allows translation
  7757 rules with string literals);
  7758 
  7759 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  7760  and Fleuriot's mechanization of analysis, including the transcendental
  7761  functions for the reals;
  7762 
  7763 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  7764 
  7765 
  7766 *** CTT ***
  7767 
  7768 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  7769 "lam" is displayed as TWO lambda-symbols
  7770 
  7771 * CTT: theory Main now available, containing everything (that is, Bool
  7772 and Arith);
  7773 
  7774 
  7775 *** General ***
  7776 
  7777 * Pure: the Simplifier has been implemented properly as a derived rule
  7778 outside of the actual kernel (at last!); the overall performance
  7779 penalty in practical applications is about 50%, while reliability of
  7780 the Isabelle inference kernel has been greatly improved;
  7781 
  7782 * print modes "brackets" and "no_brackets" control output of nested =>
  7783 (types) and ==> (props); the default behaviour is "brackets";
  7784 
  7785 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7786 as assumptions as well;
  7787 
  7788 * system: support Poly/ML 4.0;
  7789 
  7790 * system: isatool install handles KDE version 1 or 2;
  7791 
  7792 
  7793 
  7794 New in Isabelle99-1 (October 2000)
  7795 ----------------------------------
  7796 
  7797 *** Overview of INCOMPATIBILITIES ***
  7798 
  7799 * HOL: simplification of natural numbers is much changed; to partly
  7800 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7801 issue the following ML commands:
  7802 
  7803   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7804   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7805 
  7806 * HOL: simplification no longer dives into case-expressions; this is
  7807 controlled by "t.weak_case_cong" for each datatype t;
  7808 
  7809 * HOL: nat_less_induct renamed to less_induct;
  7810 
  7811 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7812 fixsome to patch .thy and .ML sources automatically;
  7813 
  7814   select_equality  -> some_equality
  7815   select_eq_Ex     -> some_eq_ex
  7816   selectI2EX       -> someI2_ex
  7817   selectI2         -> someI2
  7818   selectI          -> someI
  7819   select1_equality -> some1_equality
  7820   Eps_sym_eq       -> some_sym_eq_trivial
  7821   Eps_eq           -> some_eq_trivial
  7822 
  7823 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7824 
  7825 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7826 instead);
  7827 
  7828 * HOL: the recursion equations generated by 'recdef' are now called
  7829 f.simps instead of f.rules;
  7830 
  7831 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7832 
  7833 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7834 sometimes be needed;
  7835 
  7836 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7837 
  7838 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7839 
  7840 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7841 product is now "<*>" instead of "Times"; the lexicographic product is
  7842 now "<*lex*>" instead of "**";
  7843 
  7844 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7845 of main HOL, but was unused); better use HOL's datatype package;
  7846 
  7847 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7848 the old syntax may be recovered as follows:
  7849 
  7850   syntax (symbols)
  7851     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7852       (infixl "\\<oplus>" 100)
  7853 
  7854 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7855 
  7856 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7857 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7858 internally;
  7859 
  7860 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7861 changed from A/r to A//r;
  7862 
  7863 * ZF: new treatment of arithmetic (nat & int) may break some old
  7864 proofs;
  7865 
  7866 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7867 rulify -> rule_format, elimify -> elim_format, ...);
  7868 
  7869 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7870 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7871 should have to change intro!! to intro? only); replaced "delrule" by
  7872 "rule del";
  7873 
  7874 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7875 
  7876 * Provers: strengthened force_tac by using new first_best_tac;
  7877 
  7878 * LaTeX document preparation: several changes of isabelle.sty (see
  7879 lib/texinputs);
  7880 
  7881 
  7882 *** Document preparation ***
  7883 
  7884 * formal comments (text blocks etc.) in new-style theories may now
  7885 contain antiquotations of thm/prop/term/typ/text to be presented
  7886 according to latex print mode; concrete syntax is like this:
  7887 @{term[show_types] "f(x) = a + x"};
  7888 
  7889 * isatool mkdir provides easy setup of Isabelle session directories,
  7890 including proper document sources;
  7891 
  7892 * generated LaTeX sources are now deleted after successful run
  7893 (isatool document -c); may retain a copy somewhere else via -D option
  7894 of isatool usedir;
  7895 
  7896 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7897 style files, achieving self-contained LaTeX sources and simplifying
  7898 LaTeX debugging;
  7899 
  7900 * old-style theories now produce (crude) LaTeX output as well;
  7901 
  7902 * browser info session directories are now self-contained (may be put
  7903 on WWW server seperately); improved graphs of nested sessions; removed
  7904 graph for 'all sessions';
  7905 
  7906 * several improvements in isabelle style files; \isabellestyle{it}
  7907 produces fake math mode output; \isamarkupheader is now \section by
  7908 default; see lib/texinputs/isabelle.sty etc.;
  7909 
  7910 
  7911 *** Isar ***
  7912 
  7913 * Isar/Pure: local results and corresponding term bindings are now
  7914 subject to Hindley-Milner polymorphism (similar to ML); this
  7915 accommodates incremental type-inference very nicely;
  7916 
  7917 * Isar/Pure: new derived language element 'obtain' supports
  7918 generalized existence reasoning;
  7919 
  7920 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7921 support accumulation of results, without applying any rules yet;
  7922 useful to collect intermediate results without explicit name
  7923 references, and for use with transitivity rules with more than 2
  7924 premises;
  7925 
  7926 * Isar/Pure: scalable support for case-analysis type proofs: new
  7927 'case' language element refers to local contexts symbolically, as
  7928 produced by certain proof methods; internally, case names are attached
  7929 to theorems as "tags";
  7930 
  7931 * Isar/Pure: theory command 'hide' removes declarations from
  7932 class/type/const name spaces;
  7933 
  7934 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7935 indicate potential overloading;
  7936 
  7937 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7938 
  7939 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7940 "{a,b,c}" instead of {a,b,c};
  7941 
  7942 * Isar/Pure now provides its own version of intro/elim/dest
  7943 attributes; useful for building new logics, but beware of confusion
  7944 with the version in Provers/classical;
  7945 
  7946 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7947 case name 'antecedent';
  7948 
  7949 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7950 to the current context is now done automatically);
  7951 
  7952 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7953 for definining proof methods in ML;
  7954 
  7955 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7956 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7957 most cases, one should have to change intro!! to intro? only);
  7958 replaced "delrule" by "rule del";
  7959 
  7960 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7961 'symmetric' attribute (the latter supercedes [RS sym]);
  7962 
  7963 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7964 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7965 well (including splits);
  7966 
  7967 * Isar/Provers: Simplifier and Classical methods now support all kind
  7968 of modifiers used in the past, including 'cong', 'iff', etc.
  7969 
  7970 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7971 of Simplifier and Classical reasoner);
  7972 
  7973 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7974 now support named cases; major packages (inductive, datatype, primrec,
  7975 recdef) support case names and properly name parameters;
  7976 
  7977 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7978 monotonicity conditions are extracted to be proven at end of
  7979 calculations;
  7980 
  7981 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7982 method anyway;
  7983 
  7984 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7985 split_if split_if_asm; datatype package provides theorems foo.splits =
  7986 foo.split foo.split_asm for each datatype;
  7987 
  7988 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7989 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7990 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  7991 use "(cases (simplified))" method in proper proof texts);
  7992 
  7993 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  7994 
  7995 * Isar: names of theorems etc. may be natural numbers as well;
  7996 
  7997 * Isar: 'pr' command: optional arguments for goals_limit and
  7998 ProofContext.prems_limit; no longer prints theory contexts, but only
  7999 proof states;
  8000 
  8001 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  8002 additional print modes to be specified; e.g. "pr(latex)" will print
  8003 proof state according to the Isabelle LaTeX style;
  8004 
  8005 * Isar: improved support for emulating tactic scripts, including proof
  8006 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  8007 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  8008 (for HOL datatypes);
  8009 
  8010 * Isar: simplified (more robust) goal selection of proof methods: 1st
  8011 goal, all goals, or explicit goal specifier (tactic emulation); thus
  8012 'proof method scripts' have to be in depth-first order;
  8013 
  8014 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  8015 
  8016 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  8017 should instead use individual commands for printing items
  8018 (print_commands, print_methods etc.);
  8019 
  8020 * Isar: added 'nothing' --- the empty list of theorems;
  8021 
  8022 
  8023 *** HOL ***
  8024 
  8025 * HOL/MicroJava: formalization of a fragment of Java, together with a
  8026 corresponding virtual machine and a specification of its bytecode
  8027 verifier and a lightweight bytecode verifier, including proofs of
  8028 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  8029 Cornelia Pusch (see also the homepage of project Bali at
  8030 http://isabelle.in.tum.de/Bali/);
  8031 
  8032 * HOL/Algebra: new theory of rings and univariate polynomials, by
  8033 Clemens Ballarin;
  8034 
  8035 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  8036 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  8037 Rasmussen;
  8038 
  8039 * HOL/Lattice: fundamental concepts of lattice theory and order
  8040 structures, including duals, properties of bounds versus algebraic
  8041 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  8042 Theorem for complete lattices etc.; may also serve as a demonstration
  8043 for abstract algebraic reasoning using axiomatic type classes, and
  8044 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  8045 
  8046 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  8047 von Oheimb;
  8048 
  8049 * HOL/IMPP: extension of IMP with local variables and mutually
  8050 recursive procedures, by David von Oheimb;
  8051 
  8052 * HOL/Lambda: converted into new-style theory and document;
  8053 
  8054 * HOL/ex/Multiquote: example of multiple nested quotations and
  8055 anti-quotations -- basically a generalized version of de-Bruijn
  8056 representation; very useful in avoiding lifting of operations;
  8057 
  8058 * HOL/record: added general record equality rule to simpset; fixed
  8059 select-update simplification procedure to handle extended records as
  8060 well; admit "r" as field name;
  8061 
  8062 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  8063 other numeric types and also as the identity of groups, rings, etc.;
  8064 
  8065 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  8066 Types nat and int belong to this axclass;
  8067 
  8068 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  8069    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  8070    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  8071   two terms #m*u and #n*u are replaced by #(m+n)*u
  8072     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  8073   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  8074     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  8075 
  8076 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  8077 powerful prover for predicate logic but knows nothing of clasets; see
  8078 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  8079 
  8080 * HOL: new version of "case_tac" subsumes both boolean case split and
  8081 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  8082 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  8083 
  8084 * HOL: simplification no longer dives into case-expressions: only the
  8085 selector expression is simplified, but not the remaining arms; to
  8086 enable full simplification of case-expressions for datatype t, you may
  8087 remove t.weak_case_cong from the simpset, either globally (Delcongs
  8088 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  8089 
  8090 * HOL/recdef: the recursion equations generated by 'recdef' for
  8091 function 'f' are now called f.simps instead of f.rules; if all
  8092 termination conditions are proved automatically, these simplification
  8093 rules are added to the simpset, as in primrec; rules may be named
  8094 individually as well, resulting in a separate list of theorems for
  8095 each equation;
  8096 
  8097 * HOL/While is a new theory that provides a while-combinator. It
  8098 permits the definition of tail-recursive functions without the
  8099 provision of a termination measure. The latter is necessary once the
  8100 invariant proof rule for while is applied.
  8101 
  8102 * HOL: new (overloaded) notation for the set of elements below/above
  8103 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  8104 
  8105 * HOL: theorems impI, allI, ballI bound as "strip";
  8106 
  8107 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  8108 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  8109 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  8110 
  8111 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  8112 
  8113 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  8114 main HOL, but was unused);
  8115 
  8116 * HOL: fewer consts declared as global (e.g. have to refer to
  8117 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  8118 
  8119 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  8120 in case of overlap with user translations (e.g. judgements over
  8121 tuples); (note that the underlying logical represenation is still
  8122 bogus);
  8123 
  8124 
  8125 *** ZF ***
  8126 
  8127 * ZF: simplification automatically cancels common terms in arithmetic
  8128 expressions over nat and int;
  8129 
  8130 * ZF: new treatment of nat to minimize type-checking: all operators
  8131 coerce their operands to a natural number using the function natify,
  8132 making the algebraic laws unconditional;
  8133 
  8134 * ZF: as above, for int: operators coerce their operands to an integer
  8135 using the function intify;
  8136 
  8137 * ZF: the integer library now contains many of the usual laws for the
  8138 orderings, including $<=, and monotonicity laws for $+ and $*;
  8139 
  8140 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  8141 simplification;
  8142 
  8143 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  8144 to the simplifier and classical reasoner simultaneously;
  8145 
  8146 
  8147 *** General ***
  8148 
  8149 * Provers: blast_tac now handles actual object-logic rules as
  8150 assumptions; note that auto_tac uses blast_tac internally as well;
  8151 
  8152 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  8153 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  8154 
  8155 * Provers: delrules now handles destruct rules as well (no longer need
  8156 explicit make_elim);
  8157 
  8158 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  8159   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8160 use instead the strong form,
  8161   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8162 in HOL, FOL and ZF the function cla_make_elim will create such rules
  8163 from destruct-rules;
  8164 
  8165 * Provers: Simplifier.easy_setup provides a fast path to basic
  8166 Simplifier setup for new object-logics;
  8167 
  8168 * Pure: AST translation rules no longer require constant head on LHS;
  8169 
  8170 * Pure: improved name spaces: ambiguous output is qualified; support
  8171 for hiding of names;
  8172 
  8173 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  8174 XSYMBOL_HOME; no longer need to do manual configuration in most
  8175 situations;
  8176 
  8177 * system: compression of ML heaps images may now be controlled via -c
  8178 option of isabelle and isatool usedir (currently only observed by
  8179 Poly/ML);
  8180 
  8181 * system: isatool installfonts may handle X-Symbol fonts as well (very
  8182 useful for remote X11);
  8183 
  8184 * system: provide TAGS file for Isabelle sources;
  8185 
  8186 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  8187 order;
  8188 
  8189 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  8190 timing flag supersedes proof_timing and Toplevel.trace;
  8191 
  8192 * ML: new combinators |>> and |>>> for incremental transformations
  8193 with secondary results (e.g. certain theory extensions):
  8194 
  8195 * ML: PureThy.add_defs gets additional argument to indicate potential
  8196 overloading (usually false);
  8197 
  8198 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  8199 results;
  8200 
  8201 
  8202 
  8203 New in Isabelle99 (October 1999)
  8204 --------------------------------
  8205 
  8206 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8207 
  8208 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  8209 are no longer simplified.  (This allows the simplifier to unfold recursive
  8210 functional programs.)  To restore the old behaviour, declare
  8211 
  8212     Delcongs [if_weak_cong];
  8213 
  8214 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  8215 complement;
  8216 
  8217 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  8218 
  8219 * HOL/datatype: mutual_induct_tac no longer exists --
  8220   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  8221 
  8222 * HOL/typedef: fixed type inference for representing set; type
  8223 arguments now have to occur explicitly on the rhs as type constraints;
  8224 
  8225 * ZF: The con_defs part of an inductive definition may no longer refer
  8226 to constants declared in the same theory;
  8227 
  8228 * HOL, ZF: the function mk_cases, generated by the inductive
  8229 definition package, has lost an argument.  To simplify its result, it
  8230 uses the default simpset instead of a supplied list of theorems.
  8231 
  8232 * HOL/List: the constructors of type list are now Nil and Cons;
  8233 
  8234 * Simplifier: the type of the infix ML functions
  8235         setSSolver addSSolver setSolver addSolver
  8236 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  8237 for packaging solvers. A solver is created via
  8238         mk_solver: string -> (thm list -> int -> tactic) -> solver
  8239 where the string argument is only a comment.
  8240 
  8241 
  8242 *** Proof tools ***
  8243 
  8244 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  8245 decision procedure for linear arithmetic. Currently it is used for
  8246 types `nat', `int', and `real' in HOL (see below); it can, should and
  8247 will be instantiated for other types and logics as well.
  8248 
  8249 * The simplifier now accepts rewrite rules with flexible heads, eg
  8250      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  8251   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  8252   matching.
  8253 
  8254 
  8255 *** General ***
  8256 
  8257 * New Isabelle/Isar subsystem provides an alternative to traditional
  8258 tactical theorem proving; together with the ProofGeneral/isar user
  8259 interface it offers an interactive environment for developing human
  8260 readable proof documents (Isar == Intelligible semi-automated
  8261 reasoning); for further information see isatool doc isar-ref,
  8262 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  8263 
  8264 * improved and simplified presentation of theories: better HTML markup
  8265 (including colors), graph views in several sizes; isatool usedir now
  8266 provides a proper interface for user theories (via -P option); actual
  8267 document preparation based on (PDF)LaTeX is available as well (for
  8268 new-style theories only); see isatool doc system for more information;
  8269 
  8270 * native support for Proof General, both for classic Isabelle and
  8271 Isabelle/Isar;
  8272 
  8273 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  8274 using the graph browser tool;
  8275 
  8276 * Isabelle manuals now also available as PDF;
  8277 
  8278 * theory loader rewritten from scratch (may not be fully
  8279 bug-compatible); old loadpath variable has been replaced by show_path,
  8280 add_path, del_path, reset_path functions; new operations such as
  8281 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  8282 isatool doc ref);
  8283 
  8284 * improved isatool install: option -k creates KDE application icon,
  8285 option -p DIR installs standalone binaries;
  8286 
  8287 * added ML_PLATFORM setting (useful for cross-platform installations);
  8288 more robust handling of platform specific ML images for SML/NJ;
  8289 
  8290 * the settings environment is now statically scoped, i.e. it is never
  8291 created again in sub-processes invoked from isabelle, isatool, or
  8292 Isabelle;
  8293 
  8294 * path element specification '~~' refers to '$ISABELLE_HOME';
  8295 
  8296 * in locales, the "assumes" and "defines" parts may be omitted if
  8297 empty;
  8298 
  8299 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  8300 long arrows);
  8301 
  8302 * new print_mode "HTML";
  8303 
  8304 * new flag show_tags controls display of tags of theorems (which are
  8305 basically just comments that may be attached by some tools);
  8306 
  8307 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  8308 mode and goal output format:
  8309 
  8310 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  8311 244c244
  8312 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  8313 ---
  8314 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  8315 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  8316 181c181
  8317 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  8318 ---
  8319 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  8320 
  8321 * function bind_thms stores lists of theorems (cf. bind_thm);
  8322 
  8323 * new shorthand tactics ftac, eatac, datac, fatac;
  8324 
  8325 * qed (and friends) now accept "" as result name; in that case the
  8326 theorem is not stored, but proper checks and presentation of the
  8327 result still apply;
  8328 
  8329 * theorem database now also indexes constants "Trueprop", "all",
  8330 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  8331 
  8332 
  8333 *** HOL ***
  8334 
  8335 ** HOL arithmetic **
  8336 
  8337 * There are now decision procedures for linear arithmetic over nat and
  8338 int:
  8339 
  8340 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  8341 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  8342 are treated as atomic; subformulae not involving type `nat' or `int'
  8343 are ignored; quantified subformulae are ignored unless they are
  8344 positive universal or negative existential. The tactic has to be
  8345 invoked by hand and can be a little bit slow. In particular, the
  8346 running time is exponential in the number of occurrences of `min' and
  8347 `max', and `-' on `nat'.
  8348 
  8349 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  8350 (negated) (in)equalities among the premises and the conclusion into
  8351 account (i.e. no compound formulae) and does not know about `min' and
  8352 `max', and `-' on `nat'. It is fast and is used automatically by the
  8353 simplifier.
  8354 
  8355 NB: At the moment, these decision procedures do not cope with mixed
  8356 nat/int formulae where the two parts interact, such as `m < n ==>
  8357 int(m) < int(n)'.
  8358 
  8359 * HOL/Numeral provides a generic theory of numerals (encoded
  8360 efficiently as bit strings); setup for types nat/int/real is in place;
  8361 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  8362 int, existing theories and proof scripts may require a few additional
  8363 type constraints;
  8364 
  8365 * integer division and remainder can now be performed on constant
  8366 arguments;
  8367 
  8368 * many properties of integer multiplication, division and remainder
  8369 are now available;
  8370 
  8371 * An interface to the Stanford Validity Checker (SVC) is available through the
  8372 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  8373 are proved automatically.  SVC must be installed separately, and its results
  8374 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  8375 invocation of the underlying oracle).  For SVC see
  8376   http://verify.stanford.edu/SVC
  8377 
  8378 * IsaMakefile: the HOL-Real target now builds an actual image;
  8379 
  8380 
  8381 ** HOL misc **
  8382 
  8383 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  8384 (in Isabelle/Isar) -- by Gertrud Bauer;
  8385 
  8386 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  8387 analysis for assembly languages with subtypes;
  8388 
  8389 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  8390 -- avoids syntactic ambiguities and treats state, transition, and
  8391 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  8392 changed syntax and (many) tactics;
  8393 
  8394 * HOL/inductive: Now also handles more general introduction rules such
  8395   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  8396   theorems are now maintained within the theory (maintained via the
  8397   "mono" attribute);
  8398 
  8399 * HOL/datatype: Now also handles arbitrarily branching datatypes
  8400   (using function types) such as
  8401 
  8402   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  8403 
  8404 * HOL/record: record_simproc (part of the default simpset) takes care
  8405 of selectors applied to updated records; record_split_tac is no longer
  8406 part of the default claset; update_defs may now be removed from the
  8407 simpset in many cases; COMPATIBILITY: old behavior achieved by
  8408 
  8409   claset_ref () := claset() addSWrapper record_split_wrapper;
  8410   Delsimprocs [record_simproc]
  8411 
  8412 * HOL/typedef: fixed type inference for representing set; type
  8413 arguments now have to occur explicitly on the rhs as type constraints;
  8414 
  8415 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  8416 names rather than an ML expression;
  8417 
  8418 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  8419 supplied later.  Program schemes can be defined, such as
  8420     "While B C s = (if B s then While B C (C s) else s)"
  8421 where the well-founded relation can be chosen after B and C have been given.
  8422 
  8423 * HOL/List: the constructors of type list are now Nil and Cons;
  8424 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  8425 course, ML tools referring to List.list.op # etc. have to be adapted;
  8426 
  8427 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  8428 disabled by default; run isabelle with option -m HOL to get back to
  8429 the original Gordon/HOL-style output;
  8430 
  8431 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  8432 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  8433 
  8434 * HOL basic syntax simplified (more orthogonal): all variants of
  8435 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  8436 Eps operator is provided as well: "SOME x. P[x]";
  8437 
  8438 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  8439 
  8440 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  8441 thus available for user theories;
  8442 
  8443 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  8444 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  8445 time;
  8446 
  8447 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  8448 several times and then mp;
  8449 
  8450 
  8451 *** LK ***
  8452 
  8453 * the notation <<...>> is now available as a notation for sequences of
  8454 formulas;
  8455 
  8456 * the simplifier is now installed
  8457 
  8458 * the axiom system has been generalized (thanks to Soren Heilmann)
  8459 
  8460 * the classical reasoner now has a default rule database
  8461 
  8462 
  8463 *** ZF ***
  8464 
  8465 * new primrec section allows primitive recursive functions to be given
  8466 directly (as in HOL) over datatypes and the natural numbers;
  8467 
  8468 * new tactics induct_tac and exhaust_tac for induction (or case
  8469 analysis) over datatypes and the natural numbers;
  8470 
  8471 * the datatype declaration of type T now defines the recursor T_rec;
  8472 
  8473 * simplification automatically does freeness reasoning for datatype
  8474 constructors;
  8475 
  8476 * automatic type-inference, with AddTCs command to insert new
  8477 type-checking rules;
  8478 
  8479 * datatype introduction rules are now added as Safe Introduction rules
  8480 to the claset;
  8481 
  8482 * the syntax "if P then x else y" is now available in addition to
  8483 if(P,x,y);
  8484 
  8485 
  8486 *** Internal programming interfaces ***
  8487 
  8488 * tuned simplifier trace output; new flag debug_simp;
  8489 
  8490 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8491 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8492 
  8493 * AxClass.axclass_tac lost the theory argument;
  8494 
  8495 * tuned current_goals_markers semantics: begin / end goal avoids
  8496 printing empty lines;
  8497 
  8498 * removed prs and prs_fn hook, which was broken because it did not
  8499 include \n in its semantics, forcing writeln to add one
  8500 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8501 string -> unit if you really want to output text without newline;
  8502 
  8503 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8504 plain output, interface builders may have to enable 'isabelle_font'
  8505 mode to get Isabelle font glyphs as before;
  8506 
  8507 * refined token_translation interface; INCOMPATIBILITY: output length
  8508 now of type real instead of int;
  8509 
  8510 * theory loader actions may be traced via new ThyInfo.add_hook
  8511 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8512 your own database of information attached to *whole* theories -- as
  8513 opposed to intra-theory data slots offered via TheoryDataFun;
  8514 
  8515 * proper handling of dangling sort hypotheses (at last!);
  8516 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8517 extra sort hypotheses that can be witnessed from the type signature;
  8518 the force_strip_shyps flag is gone, any remaining shyps are simply
  8519 left in the theorem (with a warning issued by strip_shyps_warning);
  8520 
  8521 
  8522 
  8523 New in Isabelle98-1 (October 1998)
  8524 ----------------------------------
  8525 
  8526 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8527 
  8528 * several changes of automated proof tools;
  8529 
  8530 * HOL: major changes to the inductive and datatype packages, including
  8531 some minor incompatibilities of theory syntax;
  8532 
  8533 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8534 called `inj_on';
  8535 
  8536 * HOL: removed duplicate thms in Arith:
  8537   less_imp_add_less  should be replaced by  trans_less_add1
  8538   le_imp_add_le      should be replaced by  trans_le_add1
  8539 
  8540 * HOL: unary minus is now overloaded (new type constraints may be
  8541 required);
  8542 
  8543 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8544 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8545 now taken as an integer constant.
  8546 
  8547 * Pure: ML function 'theory_of' renamed to 'theory';
  8548 
  8549 
  8550 *** Proof tools ***
  8551 
  8552 * Simplifier:
  8553   1. Asm_full_simp_tac is now more aggressive.
  8554      1. It will sometimes reorient premises if that increases their power to
  8555         simplify.
  8556      2. It does no longer proceed strictly from left to right but may also
  8557         rotate premises to achieve further simplification.
  8558      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8559      old Asm_full_simp_tac in that it does not rotate premises.
  8560   2. The simplifier now knows a little bit about nat-arithmetic.
  8561 
  8562 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8563 allows for selected deletion of wrappers, by introduction of names for
  8564 wrapper functionals.  This implies that addbefore, addSbefore,
  8565 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8566 and that adding two tactics with the same name overwrites the first
  8567 one (emitting a warning).
  8568   type wrapper = (int -> tactic) -> (int -> tactic)
  8569   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8570   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8571   delWrapper, delSWrapper: claset *  string            -> claset
  8572   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8573 
  8574 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8575 semantics; addbefore now affects only the unsafe part of step_tac
  8576 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8577 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8578 by Force_tac;
  8579 
  8580 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8581 compWrapper; added safe wrapper (and access functions for it);
  8582 
  8583 * HOL/split_all_tac is now much faster and fails if there is nothing
  8584 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8585 and the names of the automatically generated variables have changed.
  8586 split_all_tac has moved within claset() from unsafe wrappers to safe
  8587 wrappers, which means that !!-bound variables are split much more
  8588 aggressively, and safe_tac and clarify_tac now split such variables.
  8589 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8590 Note: the same holds for record_split_tac, which does the job of
  8591 split_all_tac for record fields.
  8592 
  8593 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8594 permanently to the default simpset using Addsplits just like
  8595 Addsimps. They can be removed via Delsplits just like
  8596 Delsimps. Lower-case versions are also available.
  8597 
  8598 * HOL/Simplifier: The rule split_if is now part of the default
  8599 simpset. This means that the simplifier will eliminate all occurrences
  8600 of if-then-else in the conclusion of a goal. To prevent this, you can
  8601 either remove split_if completely from the default simpset by
  8602 `Delsplits [split_if]' or remove it in a specific call of the
  8603 simplifier using `... delsplits [split_if]'.  You can also add/delete
  8604 other case splitting rules to/from the default simpset: every datatype
  8605 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  8606 t is the name of the datatype).
  8607 
  8608 * Classical reasoner / Simplifier combination: new force_tac (and
  8609 derivatives Force_tac, force) combines rewriting and classical
  8610 reasoning (and whatever other tools) similarly to auto_tac, but is
  8611 aimed to solve the given subgoal completely.
  8612 
  8613 
  8614 *** General ***
  8615 
  8616 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  8617 and `goalw': the theory is no longer needed as an explicit argument -
  8618 the current theory context is used; assumptions are no longer returned
  8619 at the ML-level unless one of them starts with ==> or !!; it is
  8620 recommended to convert to these new commands using isatool fixgoal
  8621 (backup your sources first!);
  8622 
  8623 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  8624 the current theory context, and 'theory' to lookup stored theories;
  8625 
  8626 * new theory section 'locale' for declaring constants, assumptions and
  8627 definitions that have local scope;
  8628 
  8629 * new theory section 'nonterminals' for purely syntactic types;
  8630 
  8631 * new theory section 'setup' for generic ML setup functions
  8632 (e.g. package initialization);
  8633 
  8634 * the distribution now includes Isabelle icons: see
  8635 lib/logo/isabelle-{small,tiny}.xpm;
  8636 
  8637 * isatool install - install binaries with absolute references to
  8638 ISABELLE_HOME/bin;
  8639 
  8640 * isatool logo -- create instances of the Isabelle logo (as EPS);
  8641 
  8642 * print mode 'emacs' reserved for Isamode;
  8643 
  8644 * support multiple print (ast) translations per constant name;
  8645 
  8646 * theorems involving oracles are now printed with a suffixed [!];
  8647 
  8648 
  8649 *** HOL ***
  8650 
  8651 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  8652 
  8653 * HOL/inductive package reorganized and improved: now supports mutual
  8654 definitions such as
  8655 
  8656   inductive EVEN ODD
  8657     intrs
  8658       null "0 : EVEN"
  8659       oddI "n : EVEN ==> Suc n : ODD"
  8660       evenI "n : ODD ==> Suc n : EVEN"
  8661 
  8662 new theorem list "elims" contains an elimination rule for each of the
  8663 recursive sets; inductive definitions now handle disjunctive premises
  8664 correctly (also ZF);
  8665 
  8666 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  8667 "mutual_induct" no longer exists - the induction rule is always
  8668 contained in "induct";
  8669 
  8670 
  8671 * HOL/datatype package re-implemented and greatly improved: now
  8672 supports mutually recursive datatypes such as
  8673 
  8674   datatype
  8675     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  8676             | SUM ('a aexp) ('a aexp)
  8677             | DIFF ('a aexp) ('a aexp)
  8678             | NUM 'a
  8679   and
  8680     'a bexp = LESS ('a aexp) ('a aexp)
  8681             | AND ('a bexp) ('a bexp)
  8682             | OR ('a bexp) ('a bexp)
  8683 
  8684 as well as indirectly recursive datatypes such as
  8685 
  8686   datatype
  8687     ('a, 'b) term = Var 'a
  8688                   | App 'b ((('a, 'b) term) list)
  8689 
  8690 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  8691 induction on mutually / indirectly recursive datatypes.
  8692 
  8693 Primrec equations are now stored in theory and can be accessed via
  8694 <function_name>.simps.
  8695 
  8696 INCOMPATIBILITIES:
  8697 
  8698   - Theories using datatypes must now have theory Datatype as an
  8699     ancestor.
  8700   - The specific <typename>.induct_tac no longer exists - use the
  8701     generic induct_tac instead.
  8702   - natE has been renamed to nat.exhaust - use exhaust_tac
  8703     instead of res_inst_tac ... natE. Note that the variable
  8704     names in nat.exhaust differ from the names in natE, this
  8705     may cause some "fragile" proofs to fail.
  8706   - The theorems split_<typename>_case and split_<typename>_case_asm
  8707     have been renamed to <typename>.split and <typename>.split_asm.
  8708   - Since default sorts of type variables are now handled correctly,
  8709     some datatype definitions may have to be annotated with explicit
  8710     sort constraints.
  8711   - Primrec definitions no longer require function name and type
  8712     of recursive argument.
  8713 
  8714 Consider using isatool fixdatatype to adapt your theories and proof
  8715 scripts to the new package (backup your sources first!).
  8716 
  8717 
  8718 * HOL/record package: considerably improved implementation; now
  8719 includes concrete syntax for record types, terms, updates; theorems
  8720 for surjective pairing and splitting !!-bound record variables; proof
  8721 support is as follows:
  8722 
  8723   1) standard conversions (selectors or updates applied to record
  8724 constructor terms) are part of the standard simpset;
  8725 
  8726   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  8727 made part of standard simpset and claset via addIffs;
  8728 
  8729   3) a tactic for record field splitting (record_split_tac) is part of
  8730 the standard claset (addSWrapper);
  8731 
  8732 To get a better idea about these rules you may retrieve them via
  8733 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  8734 the name of your record type.
  8735 
  8736 The split tactic 3) conceptually simplifies by the following rule:
  8737 
  8738   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  8739 
  8740 Thus any record variable that is bound by meta-all will automatically
  8741 blow up into some record constructor term, consequently the
  8742 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  8743 solve record problems automatically.
  8744 
  8745 
  8746 * reorganized the main HOL image: HOL/Integ and String loaded by
  8747 default; theory Main includes everything;
  8748 
  8749 * automatic simplification of integer sums and comparisons, using cancellation;
  8750 
  8751 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  8752 
  8753 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  8754 
  8755 * many new identities for unions, intersections, set difference, etc.;
  8756 
  8757 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  8758 called split_if, split_split, split_sum_case and split_nat_case (to go
  8759 with add/delsplits);
  8760 
  8761 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  8762 (?x::unit) = (); this is made part of the default simpset, which COULD
  8763 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  8764 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  8765 unit_abs_eta_conv is added in order to counter the effect of
  8766 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  8767 %u.f();
  8768 
  8769 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  8770 makes more sense);
  8771 
  8772 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8773   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8774   disjointness reasoning but breaking a few old proofs.
  8775 
  8776 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  8777 to 'converse' from 'inverse' (for compatibility with ZF and some
  8778 literature);
  8779 
  8780 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  8781 the well-founded relation;
  8782 
  8783 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8784     Compl A.  The "Compl" syntax remains available as input syntax for this
  8785     release ONLY.
  8786 
  8787 * HOL/Update: new theory of function updates:
  8788     f(a:=b) == %x. if x=a then b else f x
  8789 may also be iterated as in f(a:=b,c:=d,...);
  8790 
  8791 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8792 
  8793 * HOL/List:
  8794   - new function list_update written xs[i:=v] that updates the i-th
  8795     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8796   - new function `upt' written [i..j(] which generates the list
  8797     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8798     bound write [i..j], which is a shorthand for [i..j+1(].
  8799   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8800 
  8801 * HOL/Arith:
  8802   - removed 'pred' (predecessor) function;
  8803   - generalized some theorems about n-1;
  8804   - many new laws about "div" and "mod";
  8805   - new laws about greatest common divisors (see theory ex/Primes);
  8806 
  8807 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8808 instead of "inverse";
  8809 
  8810 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8811   of the multiset ordering;
  8812 
  8813 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8814   (not included by default);
  8815 
  8816 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8817 
  8818 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8819   programs, i.e. different program variables may have different types.
  8820 
  8821 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8822   [previously, this check worked only if the rewrite rule was unconditional]
  8823   Now rew can involve either definitions or equalities (either == or =).
  8824 
  8825 
  8826 *** ZF ***
  8827 
  8828 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8829   only the theorems proved on ZF.ML;
  8830 
  8831 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8832   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8833   disjointness reasoning but breaking a few old proofs.
  8834 
  8835 * ZF/Update: new theory of function updates
  8836     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8837   may also be iterated as in f(a:=b,c:=d,...);
  8838 
  8839 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8840 
  8841 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8842   [previously, this check worked only if the rewrite rule was unconditional]
  8843   Now rew can involve either definitions or equalities (either == or =).
  8844 
  8845 * case_tac provided for compatibility with HOL
  8846     (like the old excluded_middle_tac, but with subgoals swapped)
  8847 
  8848 
  8849 *** Internal programming interfaces ***
  8850 
  8851 * Pure: several new basic modules made available for general use, see
  8852 also src/Pure/README;
  8853 
  8854 * improved the theory data mechanism to support encapsulation (data
  8855 kind name replaced by private Object.kind, acting as authorization
  8856 key); new type-safe user interface via functor TheoryDataFun; generic
  8857 print_data function becomes basically useless;
  8858 
  8859 * removed global_names compatibility flag -- all theory declarations
  8860 are qualified by default;
  8861 
  8862 * module Pure/Syntax now offers quote / antiquote translation
  8863 functions (useful for Hoare logic etc. with implicit dependencies);
  8864 see HOL/ex/Antiquote for an example use;
  8865 
  8866 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8867 cterm -> thm;
  8868 
  8869 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8870 subgoal;
  8871 
  8872 * Display.print_goals function moved to Locale.print_goals;
  8873 
  8874 * standard print function for goals supports current_goals_markers
  8875 variable for marking begin of proof, end of proof, start of goal; the
  8876 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8877 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8878 for example;
  8879 
  8880 
  8881 
  8882 New in Isabelle98 (January 1998)
  8883 --------------------------------
  8884 
  8885 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8886 
  8887 * changed lexical syntax of terms / types: dots made part of long
  8888 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8889 
  8890 * simpset (and claset) reference variable replaced by functions
  8891 simpset / simpset_ref;
  8892 
  8893 * no longer supports theory aliases (via merge) and non-trivial
  8894 implicit merge of thms' signatures;
  8895 
  8896 * most internal names of constants changed due to qualified names;
  8897 
  8898 * changed Pure/Sequence interface (see Pure/seq.ML);
  8899 
  8900 
  8901 *** General Changes ***
  8902 
  8903 * hierachically structured name spaces (for consts, types, axms, thms
  8904 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8905 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8906 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8907 long_names for fully qualified output names; NOTE: ML programs
  8908 (special tactics, packages etc.) referring to internal names may have
  8909 to be adapted to cope with fully qualified names; in case of severe
  8910 backward campatibility problems try setting 'global_names' at compile
  8911 time to have enrything declared within a flat name space; one may also
  8912 fine tune name declarations in theories via the 'global' and 'local'
  8913 section;
  8914 
  8915 * reimplemented the implicit simpset and claset using the new anytype
  8916 data filed in signatures; references simpset:simpset ref etc. are
  8917 replaced by functions simpset:unit->simpset and
  8918 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8919 to patch your ML files accordingly;
  8920 
  8921 * HTML output now includes theory graph data for display with Java
  8922 applet or isatool browser; data generated automatically via isatool
  8923 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8924 
  8925 * defs may now be conditional; improved rewrite_goals_tac to handle
  8926 conditional equations;
  8927 
  8928 * defs now admits additional type arguments, using TYPE('a) syntax;
  8929 
  8930 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8931 creates a new theory node; implicit merge of thms' signatures is
  8932 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8933 transfer:theory->thm->thm in (rare) cases;
  8934 
  8935 * improved handling of draft signatures / theories; draft thms (and
  8936 ctyps, cterms) are automatically promoted to real ones;
  8937 
  8938 * slightly changed interfaces for oracles: admit many per theory, named
  8939 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8940 
  8941 * print_goals: optional output of const types (set show_consts and
  8942 show_types);
  8943 
  8944 * improved output of warnings (###) and errors (***);
  8945 
  8946 * subgoal_tac displays a warning if the new subgoal has type variables;
  8947 
  8948 * removed old README and Makefiles;
  8949 
  8950 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8951 
  8952 * removed obsolete init_pps and init_database;
  8953 
  8954 * deleted the obsolete tactical STATE, which was declared by
  8955     fun STATE tacfun st = tacfun st st;
  8956 
  8957 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8958 (which abbreviates $HOME);
  8959 
  8960 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8961 use isatool fixseq to adapt your ML programs (this works for fully
  8962 qualified references to the Sequence structure only!);
  8963 
  8964 * use_thy no longer requires writable current directory; it always
  8965 reloads .ML *and* .thy file, if either one is out of date;
  8966 
  8967 
  8968 *** Classical Reasoner ***
  8969 
  8970 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8971 tactics that use classical reasoning to simplify a subgoal without
  8972 splitting it into several subgoals;
  8973 
  8974 * Safe_tac: like safe_tac but uses the default claset;
  8975 
  8976 
  8977 *** Simplifier ***
  8978 
  8979 * added simplification meta rules:
  8980     (asm_)(full_)simplify: simpset -> thm -> thm;
  8981 
  8982 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8983 logics (again);
  8984 
  8985 * added prems argument to simplification procedures;
  8986 
  8987 * HOL, FOL, ZF: added infix function `addsplits':
  8988   instead of `<simpset> setloop (split_tac <thms>)'
  8989   you can simply write `<simpset> addsplits <thms>'
  8990 
  8991 
  8992 *** Syntax ***
  8993 
  8994 * TYPE('a) syntax for type reflection terms;
  8995 
  8996 * no longer handles consts with name "" -- declare as 'syntax' instead;
  8997 
  8998 * pretty printer: changed order of mixfix annotation preference (again!);
  8999 
  9000 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  9001 
  9002 
  9003 *** HOL ***
  9004 
  9005 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9006   with `addloop' of the simplifier to faciliate case splitting in premises.
  9007 
  9008 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  9009 
  9010 * HOL/Auth: new protocol proofs including some for the Internet
  9011   protocol TLS;
  9012 
  9013 * HOL/Map: new theory of `maps' a la VDM;
  9014 
  9015 * HOL/simplifier: simplification procedures nat_cancel_sums for
  9016 cancelling out common nat summands from =, <, <= (in)equalities, or
  9017 differences; simplification procedures nat_cancel_factor for
  9018 cancelling common factor from =, <, <= (in)equalities over natural
  9019 sums; nat_cancel contains both kinds of procedures, it is installed by
  9020 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  9021 
  9022 * HOL/simplifier: terms of the form
  9023   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  9024   are rewritten to
  9025   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  9026   and those of the form
  9027   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  9028   are rewritten to
  9029   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  9030 
  9031 * HOL/datatype
  9032   Each datatype `t' now comes with a theorem `split_t_case' of the form
  9033 
  9034   P(t_case f1 ... fn x) =
  9035      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  9036         ...
  9037        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  9038      )
  9039 
  9040   and a theorem `split_t_case_asm' of the form
  9041 
  9042   P(t_case f1 ... fn x) =
  9043     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  9044         ...
  9045        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  9046      )
  9047   which can be added to a simpset via `addsplits'. The existing theorems
  9048   expand_list_case and expand_option_case have been renamed to
  9049   split_list_case and split_option_case.
  9050 
  9051 * HOL/Arithmetic:
  9052   - `pred n' is automatically converted to `n-1'.
  9053     Users are strongly encouraged not to use `pred' any longer,
  9054     because it will disappear altogether at some point.
  9055   - Users are strongly encouraged to write "0 < n" rather than
  9056     "n ~= 0". Theorems and proof tools have been modified towards this
  9057     `standard'.
  9058 
  9059 * HOL/Lists:
  9060   the function "set_of_list" has been renamed "set" (and its theorems too);
  9061   the function "nth" now takes its arguments in the reverse order and
  9062   has acquired the infix notation "!" as in "xs!n".
  9063 
  9064 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  9065 
  9066 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  9067   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  9068 
  9069 * HOL/record: extensible records with schematic structural subtyping
  9070 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  9071 still lacks various theorems and concrete record syntax;
  9072 
  9073 
  9074 *** HOLCF ***
  9075 
  9076 * removed "axioms" and "generated by" sections;
  9077 
  9078 * replaced "ops" section by extended "consts" section, which is capable of
  9079   handling the continuous function space "->" directly;
  9080 
  9081 * domain package:
  9082   . proves theorems immediately and stores them in the theory,
  9083   . creates hierachical name space,
  9084   . now uses normal mixfix annotations (instead of cinfix...),
  9085   . minor changes to some names and values (for consistency),
  9086   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  9087   . separator between mutual domain defs: changed "," to "and",
  9088   . improved handling of sort constraints;  now they have to
  9089     appear on the left-hand side of the equations only;
  9090 
  9091 * fixed LAM <x,y,zs>.b syntax;
  9092 
  9093 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  9094 adm (%x. P (t x)), where P is chainfinite and t continuous;
  9095 
  9096 
  9097 *** FOL and ZF ***
  9098 
  9099 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9100   with `addloop' of the simplifier to faciliate case splitting in premises.
  9101 
  9102 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  9103 in HOL, they strip ALL and --> from proved theorems;
  9104 
  9105 
  9106 
  9107 New in Isabelle94-8 (May 1997)
  9108 ------------------------------
  9109 
  9110 *** General Changes ***
  9111 
  9112 * new utilities to build / run / maintain Isabelle etc. (in parts
  9113 still somewhat experimental); old Makefiles etc. still functional;
  9114 
  9115 * new 'Isabelle System Manual';
  9116 
  9117 * INSTALL text, together with ./configure and ./build scripts;
  9118 
  9119 * reimplemented type inference for greater efficiency, better error
  9120 messages and clean internal interface;
  9121 
  9122 * prlim command for dealing with lots of subgoals (an easier way of
  9123 setting goals_limit);
  9124 
  9125 
  9126 *** Syntax ***
  9127 
  9128 * supports alternative (named) syntax tables (parser and pretty
  9129 printer); internal interface is provided by add_modesyntax(_i);
  9130 
  9131 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  9132 be used in conjunction with the Isabelle symbol font; uses the
  9133 "symbols" syntax table;
  9134 
  9135 * added token_translation interface (may translate name tokens in
  9136 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  9137 the current print_mode); IMPORTANT: user print translation functions
  9138 are responsible for marking newly introduced bounds
  9139 (Syntax.mark_boundT);
  9140 
  9141 * token translations for modes "xterm" and "xterm_color" that display
  9142 names in bold, underline etc. or colors (which requires a color
  9143 version of xterm);
  9144 
  9145 * infixes may now be declared with names independent of their syntax;
  9146 
  9147 * added typed_print_translation (like print_translation, but may
  9148 access type of constant);
  9149 
  9150 
  9151 *** Classical Reasoner ***
  9152 
  9153 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  9154 some limitations.  Blast_tac...
  9155   + ignores addss, addbefore, addafter; this restriction is intrinsic
  9156   + ignores elimination rules that don't have the correct format
  9157         (the conclusion MUST be a formula variable)
  9158   + ignores types, which can make HOL proofs fail
  9159   + rules must not require higher-order unification, e.g. apply_type in ZF
  9160     [message "Function Var's argument not a bound variable" relates to this]
  9161   + its proof strategy is more general but can actually be slower
  9162 
  9163 * substitution with equality assumptions no longer permutes other
  9164 assumptions;
  9165 
  9166 * minor changes in semantics of addafter (now called addaltern); renamed
  9167 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  9168 (and access functions for it);
  9169 
  9170 * improved combination of classical reasoner and simplifier:
  9171   + functions for handling clasimpsets
  9172   + improvement of addss: now the simplifier is called _after_ the
  9173     safe steps.
  9174   + safe variant of addss called addSss: uses safe simplifications
  9175     _during_ the safe steps. It is more complete as it allows multiple
  9176     instantiations of unknowns (e.g. with slow_tac).
  9177 
  9178 *** Simplifier ***
  9179 
  9180 * added interface for simplification procedures (functions that
  9181 produce *proven* rewrite rules on the fly, depending on current
  9182 redex);
  9183 
  9184 * ordering on terms as parameter (used for ordered rewriting);
  9185 
  9186 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  9187 
  9188 * the solver is now split into a safe and an unsafe part.
  9189 This should be invisible for the normal user, except that the
  9190 functions setsolver and addsolver have been renamed to setSolver and
  9191 addSolver; added safe_asm_full_simp_tac;
  9192 
  9193 
  9194 *** HOL ***
  9195 
  9196 * a generic induction tactic `induct_tac' which works for all datatypes and
  9197 also for type `nat';
  9198 
  9199 * a generic case distinction tactic `exhaust_tac' which works for all
  9200 datatypes and also for type `nat';
  9201 
  9202 * each datatype comes with a function `size';
  9203 
  9204 * patterns in case expressions allow tuple patterns as arguments to
  9205 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  9206 
  9207 * primrec now also works with type nat;
  9208 
  9209 * recdef: a new declaration form, allows general recursive functions to be
  9210 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  9211 
  9212 * the constant for negation has been renamed from "not" to "Not" to
  9213 harmonize with FOL, ZF, LK, etc.;
  9214 
  9215 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  9216 infinite lists;
  9217 
  9218 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  9219 
  9220 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  9221 problems in commutative rings, using axiomatic type classes for + and *;
  9222 
  9223 * more examples in HOL/MiniML and HOL/Auth;
  9224 
  9225 * more default rewrite rules for quantifiers, union/intersection;
  9226 
  9227 * a new constant `arbitrary == @x.False';
  9228 
  9229 * HOLCF/IOA replaces old HOL/IOA;
  9230 
  9231 * HOLCF changes: derived all rules and arities
  9232   + axiomatic type classes instead of classes
  9233   + typedef instead of faking type definitions
  9234   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  9235   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  9236   + eliminated the types void, one, tr
  9237   + use unit lift and bool lift (with translations) instead of one and tr
  9238   + eliminated blift from Lift3.thy (use Def instead of blift)
  9239   all eliminated rules are derived as theorems --> no visible changes ;
  9240 
  9241 
  9242 *** ZF ***
  9243 
  9244 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  9245 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  9246 as ZF_cs addSIs [equalityI];
  9247 
  9248 
  9249 
  9250 New in Isabelle94-7 (November 96)
  9251 ---------------------------------
  9252 
  9253 * allowing negative levels (as offsets) in prlev and choplev;
  9254 
  9255 * super-linear speedup for large simplifications;
  9256 
  9257 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  9258 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  9259 FAIL); can suppress it using the command Delsimps (ex_simps @
  9260 all_simps); De Morgan laws are also now included, by default;
  9261 
  9262 * improved printing of ==>  :  ~:
  9263 
  9264 * new object-logic "Sequents" adds linear logic, while replacing LK
  9265 and Modal (thanks to Sara Kalvala);
  9266 
  9267 * HOL/Auth: correctness proofs for authentication protocols;
  9268 
  9269 * HOL: new auto_tac combines rewriting and classical reasoning (many
  9270 examples on HOL/Auth);
  9271 
  9272 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  9273 the rewriter and classical reasoner simultaneously;
  9274 
  9275 * function uresult no longer returns theorems in "standard" format;
  9276 regain previous version by: val uresult = standard o uresult;
  9277 
  9278 
  9279 
  9280 New in Isabelle94-6
  9281 -------------------
  9282 
  9283 * oracles -- these establish an interface between Isabelle and trusted
  9284 external reasoners, which may deliver results as theorems;
  9285 
  9286 * proof objects (in particular record all uses of oracles);
  9287 
  9288 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  9289 
  9290 * "constdefs" section in theory files;
  9291 
  9292 * "primrec" section (HOL) no longer requires names;
  9293 
  9294 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  9295 
  9296 
  9297 
  9298 New in Isabelle94-5
  9299 -------------------
  9300 
  9301 * reduced space requirements;
  9302 
  9303 * automatic HTML generation from theories;
  9304 
  9305 * theory files no longer require "..." (quotes) around most types;
  9306 
  9307 * new examples, including two proofs of the Church-Rosser theorem;
  9308 
  9309 * non-curried (1994) version of HOL is no longer distributed;
  9310 
  9311 
  9312 
  9313 New in Isabelle94-4
  9314 -------------------
  9315 
  9316 * greatly reduced space requirements;
  9317 
  9318 * theory files (.thy) no longer require \...\ escapes at line breaks;
  9319 
  9320 * searchable theorem database (see the section "Retrieving theorems" on
  9321 page 8 of the Reference Manual);
  9322 
  9323 * new examples, including Grabczewski's monumental case study of the
  9324 Axiom of Choice;
  9325 
  9326 * The previous version of HOL renamed to Old_HOL;
  9327 
  9328 * The new version of HOL (previously called CHOL) uses a curried syntax
  9329 for functions.  Application looks like f a b instead of f(a,b);
  9330 
  9331 * Mutually recursive inductive definitions finally work in HOL;
  9332 
  9333 * In ZF, pattern-matching on tuples is now available in all abstractions and
  9334 translates to the operator "split";
  9335 
  9336 
  9337 
  9338 New in Isabelle94-3
  9339 -------------------
  9340 
  9341 * new infix operator, addss, allowing the classical reasoner to
  9342 perform simplification at each step of its search.  Example:
  9343         fast_tac (cs addss ss)
  9344 
  9345 * a new logic, CHOL, the same as HOL, but with a curried syntax
  9346 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  9347 look like (a,b) instead of <a,b>;
  9348 
  9349 * PLEASE NOTE: CHOL will eventually replace HOL!
  9350 
  9351 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  9352 It translates to the operator "split".  A new theory of integers is available;
  9353 
  9354 * In ZF, integer numerals now denote two's-complement binary integers.
  9355 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  9356 
  9357 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  9358 of the Axiom of Choice;
  9359 
  9360 
  9361 
  9362 New in Isabelle94-2
  9363 -------------------
  9364 
  9365 * Significantly faster resolution;
  9366 
  9367 * the different sections in a .thy file can now be mixed and repeated
  9368 freely;
  9369 
  9370 * Database of theorems for FOL, HOL and ZF.  New
  9371 commands including qed, qed_goal and bind_thm store theorems in the database.
  9372 
  9373 * Simple database queries: return a named theorem (get_thm) or all theorems of
  9374 a given theory (thms_of), or find out what theory a theorem was proved in
  9375 (theory_of_thm);
  9376 
  9377 * Bugs fixed in the inductive definition and datatype packages;
  9378 
  9379 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  9380 and HOL_dup_cs obsolete;
  9381 
  9382 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  9383 have been removed;
  9384 
  9385 * Simpler definition of function space in ZF;
  9386 
  9387 * new results about cardinal and ordinal arithmetic in ZF;
  9388 
  9389 * 'subtype' facility in HOL for introducing new types as subsets of existing
  9390 types;
  9391 
  9392 :mode=text:wrap=hard:maxLineLen=72: