NEWS
author wenzelm
Sun, 15 Apr 2012 14:50:09 +0200
changeset 48355 e94cc23d434a
parent 48353 a83b25e5bad3
child 48366 573ca05db948
permissions -rw-r--r--
some coverage of bundled declarations;
     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 
   134 * Discontinued old Tutorial on Isar ("isar-overview");
   135 
   136 * Type 'a set is now a proper type constructor (just as before
   137 Isabelle2008).  Definitions mem_def and Collect_def have disappeared.
   138 Non-trivial INCOMPATIBILITY.  For developments keeping predicates and
   139 sets separate, it is often sufficient to rephrase sets S accidentally
   140 used as predicates by "%x. x : S" and predicates P accidentally used
   141 as sets by "{x. P x}".  Corresponding proofs in a first step should be
   142 pruned from any tinkering with former theorems mem_def and Collect_def
   143 as far as possible.
   144 
   145 For developments which deliberately mixed predicates and sets, a
   146 planning step is necessary to determine what should become a predicate
   147 and what a set.  It can be helpful to carry out that step in
   148 Isabelle2011-1 before jumping right into the current release.
   149 
   150 * The representation of numerals has changed.  Datatype "num"
   151 represents strictly positive binary numerals, along with functions
   152 "numeral :: num => 'a" and "neg_numeral :: num => 'a" to represent
   153 positive and negated numeric literals, respectively. (See definitions
   154 in ~~/src/HOL/Num.thy.) Potential INCOMPATIBILITY, some user theories
   155 may require adaptations as follows:
   156 
   157   - Theorems with number_ring or number_semiring constraints: These
   158     classes are gone; use comm_ring_1 or comm_semiring_1 instead.
   159 
   160   - Theories defining numeric types: Remove number, number_semiring,
   161     and number_ring instances. Defer all theorems about numerals until
   162     after classes one and semigroup_add have been instantiated.
   163 
   164   - Numeral-only simp rules: Replace each rule having a "number_of v"
   165     pattern with two copies, one for numeral and one for neg_numeral.
   166 
   167   - Theorems about subclasses of semiring_1 or ring_1: These classes
   168     automatically support numerals now, so more simp rules and
   169     simprocs may now apply within the proof.
   170 
   171   - Definitions and theorems using old constructors Pls/Min/Bit0/Bit1:
   172     Redefine using other integer operations.
   173 
   174 * Code generation by default implements sets as container type rather
   175 than predicates.  INCOMPATIBILITY.
   176 
   177 * New proof import from HOL Light: Faster, simpler, and more scalable.
   178 Requires a proof bundle, which is available as an external component.
   179 Discontinued old (and mostly dead) Importer for HOL4 and HOL Light.
   180 INCOMPATIBILITY.
   181 
   182 * New type synonym 'a rel = ('a * 'a) set
   183 
   184 * Theory Divides: Discontinued redundant theorems about div and mod.
   185 INCOMPATIBILITY, use the corresponding generic theorems instead.
   186 
   187   DIVISION_BY_ZERO ~> div_by_0, mod_by_0
   188   zdiv_self ~> div_self
   189   zmod_self ~> mod_self
   190   zdiv_zero ~> div_0
   191   zmod_zero ~> mod_0
   192   zdiv_zmod_equality ~> div_mod_equality2
   193   zdiv_zmod_equality2 ~> div_mod_equality
   194   zmod_zdiv_trivial ~> mod_div_trivial
   195   zdiv_zminus_zminus ~> div_minus_minus
   196   zmod_zminus_zminus ~> mod_minus_minus
   197   zdiv_zminus2 ~> div_minus_right
   198   zmod_zminus2 ~> mod_minus_right
   199   zdiv_minus1_right ~> div_minus1_right
   200   zmod_minus1_right ~> mod_minus1_right
   201   zdvd_mult_div_cancel ~> dvd_mult_div_cancel
   202   zmod_zmult1_eq ~> mod_mult_right_eq
   203   zpower_zmod ~> power_mod
   204   zdvd_zmod ~> dvd_mod
   205   zdvd_zmod_imp_zdvd ~> dvd_mod_imp_dvd
   206   mod_mult_distrib ~> mult_mod_left
   207   mod_mult_distrib2 ~> mult_mod_right
   208 
   209 * Removed redundant theorems nat_mult_2 and nat_mult_2_right; use
   210 generic mult_2 and mult_2_right instead. INCOMPATIBILITY.
   211 
   212 * More default pred/set conversions on a couple of relation operations
   213 and predicates.  Added powers of predicate relations.  Consolidation
   214 of some relation theorems:
   215 
   216   converse_def ~> converse_unfold
   217   rel_comp_def ~> rel_comp_unfold
   218   symp_def ~> (dropped, use symp_def and sym_def instead)
   219   transp_def ~> transp_trans
   220   Domain_def ~> Domain_unfold
   221   Range_def ~> Domain_converse [symmetric]
   222 
   223 Generalized theorems INF_INT_eq, INF_INT_eq2, SUP_UN_eq, SUP_UN_eq2.
   224 
   225 See theory "Relation" for examples for making use of pred/set
   226 conversions by means of attributes "to_set" and "to_pred".
   227 
   228 INCOMPATIBILITY.
   229 
   230 * Consolidated various theorem names relating to Finite_Set.fold
   231 combinator:
   232 
   233   inf_INFI_fold_inf ~> inf_INF_fold_inf
   234   sup_SUPR_fold_sup ~> sup_SUP_fold_sup
   235   INFI_fold_inf ~> INF_fold_inf
   236   SUPR_fold_sup ~> SUP_fold_sup
   237   union_set ~> union_set_fold
   238   minus_set ~> minus_set_fold
   239 
   240 INCOMPATIBILITY.
   241 
   242 * Consolidated theorem names concerning fold combinators:
   243 
   244   INFI_set_fold ~> INF_set_fold
   245   SUPR_set_fold ~> SUP_set_fold
   246   INF_code ~> INF_set_foldr
   247   SUP_code ~> SUP_set_foldr
   248   foldr.simps ~> foldr.simps (in point-free formulation)
   249   foldr_fold_rev ~> foldr_conv_fold
   250   foldl_fold ~> foldl_conv_fold
   251   foldr_foldr ~> foldr_conv_foldl
   252   foldl_foldr ~> foldl_conv_foldr
   253 
   254 INCOMPATIBILITY.
   255 
   256 * Dropped rarely useful theorems concerning fold combinators:
   257 foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
   258 rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
   259 concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
   260 foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
   261 listsum_conv_fold, listsum_foldl, sort_foldl_insort, foldl_assoc,
   262 foldr_conv_foldl, start_le_sum, elem_le_sum, sum_eq_0_conv.
   263 INCOMPATIBILITY.  For the common phrases "%xs. List.foldr plus xs 0"
   264 and "List.foldl plus 0", prefer "List.listsum".  Otherwise it can be
   265 useful to boil down "List.foldr" and "List.foldl" to "List.fold" by
   266 unfolding "foldr_conv_fold" and "foldl_conv_fold".
   267 
   268 * Dropped lemmas minus_set_foldr, union_set_foldr, union_coset_foldr,
   269 inter_coset_foldr, Inf_fin_set_foldr, Sup_fin_set_foldr,
   270 Min_fin_set_foldr, Max_fin_set_foldr, Inf_set_foldr, Sup_set_foldr,
   271 INF_set_foldr, SUP_set_foldr.  INCOMPATIBILITY.  Prefer corresponding
   272 lemmas over fold rather than foldr, or make use of lemmas
   273 fold_conv_foldr and fold_rev.
   274 
   275 * Congruence rules Option.map_cong and Option.bind_cong for recursion
   276 through option types.
   277 
   278 * Concrete syntax for case expressions includes constraints for source
   279 positions, and thus produces Prover IDE markup for its bindings.
   280 INCOMPATIBILITY for old-style syntax translations that augment the
   281 pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of
   282 one_case.
   283 
   284 * Discontinued configuration option "syntax_positions": atomic terms
   285 in parse trees are always annotated by position constraints.
   286 
   287 * Finite_Set.fold now qualified.  INCOMPATIBILITY.
   288 
   289 * Renamed some facts on canonical fold on lists, in order to avoid
   290 problems with interpretation involving corresponding facts on foldl
   291 with the same base names:
   292 
   293   fold_set_remdups ~> fold_set_fold_remdups
   294   fold_set ~> fold_set_fold
   295   fold1_set ~> fold1_set_fold
   296 
   297 INCOMPATIBILITY.
   298 
   299 * Renamed facts about the power operation on relations, i.e., relpow
   300 to match the constant's name:
   301 
   302   rel_pow_1 ~> relpow_1
   303   rel_pow_0_I ~> relpow_0_I
   304   rel_pow_Suc_I ~> relpow_Suc_I
   305   rel_pow_Suc_I2 ~> relpow_Suc_I2
   306   rel_pow_0_E ~> relpow_0_E
   307   rel_pow_Suc_E ~> relpow_Suc_E
   308   rel_pow_E ~> relpow_E
   309   rel_pow_Suc_D2 ~> relpow_Suc_D2
   310   rel_pow_Suc_E2 ~> relpow_Suc_E2
   311   rel_pow_Suc_D2' ~> relpow_Suc_D2'
   312   rel_pow_E2 ~> relpow_E2
   313   rel_pow_add ~> relpow_add
   314   rel_pow_commute ~> relpow
   315   rel_pow_empty ~> relpow_empty:
   316   rtrancl_imp_UN_rel_pow ~> rtrancl_imp_UN_relpow
   317   rel_pow_imp_rtrancl ~> relpow_imp_rtrancl
   318   rtrancl_is_UN_rel_pow ~> rtrancl_is_UN_relpow
   319   rtrancl_imp_rel_pow ~> rtrancl_imp_relpow
   320   rel_pow_fun_conv ~> relpow_fun_conv
   321   rel_pow_finite_bounded1 ~> relpow_finite_bounded1
   322   rel_pow_finite_bounded ~> relpow_finite_bounded
   323   rtrancl_finite_eq_rel_pow ~> rtrancl_finite_eq_relpow
   324   trancl_finite_eq_rel_pow ~> trancl_finite_eq_relpow
   325   single_valued_rel_pow ~> single_valued_relpow
   326 
   327 INCOMPATIBILITY.
   328 
   329 * Theory Relation: Consolidated constant name for relation composition
   330 and corresponding theorem names:
   331 
   332   - Renamed constant rel_comp to relcomp
   333 
   334   - Dropped abbreviation pred_comp. Use relcompp instead.
   335 
   336   - Renamed theorems:
   337 
   338     rel_compI ~> relcompI
   339     rel_compEpair ~> relcompEpair
   340     rel_compE ~> relcompE
   341     pred_comp_rel_comp_eq ~> relcompp_relcomp_eq
   342     rel_comp_empty1 ~> relcomp_empty1
   343     rel_comp_mono ~> relcomp_mono
   344     rel_comp_subset_Sigma ~> relcomp_subset_Sigma
   345     rel_comp_distrib ~> relcomp_distrib
   346     rel_comp_distrib2 ~> relcomp_distrib2
   347     rel_comp_UNION_distrib ~> relcomp_UNION_distrib
   348     rel_comp_UNION_distrib2 ~> relcomp_UNION_distrib2
   349     single_valued_rel_comp ~> single_valued_relcomp
   350     rel_comp_unfold ~> relcomp_unfold
   351     converse_rel_comp ~> converse_relcomp
   352     pred_compI ~> relcomppI
   353     pred_compE ~> relcomppE
   354     pred_comp_bot1 ~> relcompp_bot1
   355     pred_comp_bot2 ~> relcompp_bot2
   356     transp_pred_comp_less_eq ~> transp_relcompp_less_eq
   357     pred_comp_mono ~> relcompp_mono
   358     pred_comp_distrib ~> relcompp_distrib
   359     pred_comp_distrib2 ~> relcompp_distrib2
   360     converse_pred_comp ~> converse_relcompp
   361 
   362     finite_rel_comp ~> finite_relcomp
   363 
   364     set_rel_comp ~> set_relcomp
   365 
   366 INCOMPATIBILITY.
   367 
   368 * New theory HOL/Library/DAList provides an abstract type for
   369 association lists with distinct keys.
   370 
   371 * 'datatype' specifications allow explicit sort constraints.
   372 
   373 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
   374 use theory HOL/Library/Nat_Bijection instead.
   375 
   376 * Theory HOL/Library/RBT_Impl: Backing implementation of red-black
   377 trees is now inside a type class context.  Names of affected
   378 operations and lemmas have been prefixed by rbt_.  INCOMPATIBILITY for
   379 theories working directly with raw red-black trees, adapt the names as
   380 follows:
   381 
   382   Operations:
   383   bulkload -> rbt_bulkload
   384   del_from_left -> rbt_del_from_left
   385   del_from_right -> rbt_del_from_right
   386   del -> rbt_del
   387   delete -> rbt_delete
   388   ins -> rbt_ins
   389   insert -> rbt_insert
   390   insertw -> rbt_insert_with
   391   insert_with_key -> rbt_insert_with_key
   392   map_entry -> rbt_map_entry
   393   lookup -> rbt_lookup
   394   sorted -> rbt_sorted
   395   tree_greater -> rbt_greater
   396   tree_less -> rbt_less
   397   tree_less_symbol -> rbt_less_symbol
   398   union -> rbt_union
   399   union_with -> rbt_union_with
   400   union_with_key -> rbt_union_with_key
   401 
   402   Lemmas:
   403   balance_left_sorted -> balance_left_rbt_sorted
   404   balance_left_tree_greater -> balance_left_rbt_greater
   405   balance_left_tree_less -> balance_left_rbt_less
   406   balance_right_sorted -> balance_right_rbt_sorted
   407   balance_right_tree_greater -> balance_right_rbt_greater
   408   balance_right_tree_less -> balance_right_rbt_less
   409   balance_sorted -> balance_rbt_sorted
   410   balance_tree_greater -> balance_rbt_greater
   411   balance_tree_less -> balance_rbt_less
   412   bulkload_is_rbt -> rbt_bulkload_is_rbt
   413   combine_sorted -> combine_rbt_sorted
   414   combine_tree_greater -> combine_rbt_greater
   415   combine_tree_less -> combine_rbt_less
   416   delete_in_tree -> rbt_delete_in_tree
   417   delete_is_rbt -> rbt_delete_is_rbt
   418   del_from_left_tree_greater -> rbt_del_from_left_rbt_greater
   419   del_from_left_tree_less -> rbt_del_from_left_rbt_less
   420   del_from_right_tree_greater -> rbt_del_from_right_rbt_greater
   421   del_from_right_tree_less -> rbt_del_from_right_rbt_less
   422   del_in_tree -> rbt_del_in_tree
   423   del_inv1_inv2 -> rbt_del_inv1_inv2
   424   del_sorted -> rbt_del_rbt_sorted
   425   del_tree_greater -> rbt_del_rbt_greater
   426   del_tree_less -> rbt_del_rbt_less
   427   dom_lookup_Branch -> dom_rbt_lookup_Branch
   428   entries_lookup -> entries_rbt_lookup
   429   finite_dom_lookup -> finite_dom_rbt_lookup
   430   insert_sorted -> rbt_insert_rbt_sorted
   431   insertw_is_rbt -> rbt_insertw_is_rbt
   432   insertwk_is_rbt -> rbt_insertwk_is_rbt
   433   insertwk_sorted -> rbt_insertwk_rbt_sorted
   434   insertw_sorted -> rbt_insertw_rbt_sorted
   435   ins_sorted -> ins_rbt_sorted
   436   ins_tree_greater -> ins_rbt_greater
   437   ins_tree_less -> ins_rbt_less
   438   is_rbt_sorted -> is_rbt_rbt_sorted
   439   lookup_balance -> rbt_lookup_balance
   440   lookup_bulkload -> rbt_lookup_rbt_bulkload
   441   lookup_delete -> rbt_lookup_rbt_delete
   442   lookup_Empty -> rbt_lookup_Empty
   443   lookup_from_in_tree -> rbt_lookup_from_in_tree
   444   lookup_in_tree -> rbt_lookup_in_tree
   445   lookup_ins -> rbt_lookup_ins
   446   lookup_insert -> rbt_lookup_rbt_insert
   447   lookup_insertw -> rbt_lookup_rbt_insertw
   448   lookup_insertwk -> rbt_lookup_rbt_insertwk
   449   lookup_keys -> rbt_lookup_keys
   450   lookup_map -> rbt_lookup_map
   451   lookup_map_entry -> rbt_lookup_rbt_map_entry
   452   lookup_tree_greater -> rbt_lookup_rbt_greater
   453   lookup_tree_less -> rbt_lookup_rbt_less
   454   lookup_union -> rbt_lookup_rbt_union
   455   map_entry_color_of -> rbt_map_entry_color_of
   456   map_entry_inv1 -> rbt_map_entry_inv1
   457   map_entry_inv2 -> rbt_map_entry_inv2
   458   map_entry_is_rbt -> rbt_map_entry_is_rbt
   459   map_entry_sorted -> rbt_map_entry_rbt_sorted
   460   map_entry_tree_greater -> rbt_map_entry_rbt_greater
   461   map_entry_tree_less -> rbt_map_entry_rbt_less
   462   map_tree_greater -> map_rbt_greater
   463   map_tree_less -> map_rbt_less
   464   map_sorted -> map_rbt_sorted
   465   paint_sorted -> paint_rbt_sorted
   466   paint_lookup -> paint_rbt_lookup
   467   paint_tree_greater -> paint_rbt_greater
   468   paint_tree_less -> paint_rbt_less
   469   sorted_entries -> rbt_sorted_entries
   470   tree_greater_eq_trans -> rbt_greater_eq_trans
   471   tree_greater_nit -> rbt_greater_nit
   472   tree_greater_prop -> rbt_greater_prop
   473   tree_greater_simps -> rbt_greater_simps
   474   tree_greater_trans -> rbt_greater_trans
   475   tree_less_eq_trans -> rbt_less_eq_trans
   476   tree_less_nit -> rbt_less_nit
   477   tree_less_prop -> rbt_less_prop
   478   tree_less_simps -> rbt_less_simps
   479   tree_less_trans -> rbt_less_trans
   480   tree_ord_props -> rbt_ord_props
   481   union_Branch -> rbt_union_Branch
   482   union_is_rbt -> rbt_union_is_rbt
   483   unionw_is_rbt -> rbt_unionw_is_rbt
   484   unionwk_is_rbt -> rbt_unionwk_is_rbt
   485   unionwk_sorted -> rbt_unionwk_rbt_sorted
   486 
   487 * Session HOL-Word: Discontinued many redundant theorems specific to
   488 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
   489 instead.
   490 
   491   word_sub_alt ~> word_sub_wi
   492   word_add_alt ~> word_add_def
   493   word_mult_alt ~> word_mult_def
   494   word_minus_alt ~> word_minus_def
   495   word_0_alt ~> word_0_wi
   496   word_1_alt ~> word_1_wi
   497   word_add_0 ~> add_0_left
   498   word_add_0_right ~> add_0_right
   499   word_mult_1 ~> mult_1_left
   500   word_mult_1_right ~> mult_1_right
   501   word_add_commute ~> add_commute
   502   word_add_assoc ~> add_assoc
   503   word_add_left_commute ~> add_left_commute
   504   word_mult_commute ~> mult_commute
   505   word_mult_assoc ~> mult_assoc
   506   word_mult_left_commute ~> mult_left_commute
   507   word_left_distrib ~> left_distrib
   508   word_right_distrib ~> right_distrib
   509   word_left_minus ~> left_minus
   510   word_diff_0_right ~> diff_0_right
   511   word_diff_self ~> diff_self
   512   word_sub_def ~> diff_minus
   513   word_diff_minus ~> diff_minus
   514   word_add_ac ~> add_ac
   515   word_mult_ac ~> mult_ac
   516   word_plus_ac0 ~> add_0_left add_0_right add_ac
   517   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
   518   word_order_trans ~> order_trans
   519   word_order_refl ~> order_refl
   520   word_order_antisym ~> order_antisym
   521   word_order_linear ~> linorder_linear
   522   lenw1_zero_neq_one ~> zero_neq_one
   523   word_number_of_eq ~> number_of_eq
   524   word_of_int_add_hom ~> wi_hom_add
   525   word_of_int_sub_hom ~> wi_hom_sub
   526   word_of_int_mult_hom ~> wi_hom_mult
   527   word_of_int_minus_hom ~> wi_hom_neg
   528   word_of_int_succ_hom ~> wi_hom_succ
   529   word_of_int_pred_hom ~> wi_hom_pred
   530   word_of_int_0_hom ~> word_0_wi
   531   word_of_int_1_hom ~> word_1_wi
   532 
   533 * Clarified attribute "mono_set": pure declaration without modifying
   534 the result of the fact expression.
   535 
   536 * "Transitive_Closure.ntrancl": bounded transitive closure on
   537 relations.
   538 
   539 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
   540 
   541 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
   542 
   543 * Theory Int: Discontinued many legacy theorems specific to type int.
   544 INCOMPATIBILITY, use the corresponding generic theorems instead.
   545 
   546   zminus_zminus ~> minus_minus
   547   zminus_0 ~> minus_zero
   548   zminus_zadd_distrib ~> minus_add_distrib
   549   zadd_commute ~> add_commute
   550   zadd_assoc ~> add_assoc
   551   zadd_left_commute ~> add_left_commute
   552   zadd_ac ~> add_ac
   553   zmult_ac ~> mult_ac
   554   zadd_0 ~> add_0_left
   555   zadd_0_right ~> add_0_right
   556   zadd_zminus_inverse2 ~> left_minus
   557   zmult_zminus ~> mult_minus_left
   558   zmult_commute ~> mult_commute
   559   zmult_assoc ~> mult_assoc
   560   zadd_zmult_distrib ~> left_distrib
   561   zadd_zmult_distrib2 ~> right_distrib
   562   zdiff_zmult_distrib ~> left_diff_distrib
   563   zdiff_zmult_distrib2 ~> right_diff_distrib
   564   zmult_1 ~> mult_1_left
   565   zmult_1_right ~> mult_1_right
   566   zle_refl ~> order_refl
   567   zle_trans ~> order_trans
   568   zle_antisym ~> order_antisym
   569   zle_linear ~> linorder_linear
   570   zless_linear ~> linorder_less_linear
   571   zadd_left_mono ~> add_left_mono
   572   zadd_strict_right_mono ~> add_strict_right_mono
   573   zadd_zless_mono ~> add_less_le_mono
   574   int_0_less_1 ~> zero_less_one
   575   int_0_neq_1 ~> zero_neq_one
   576   zless_le ~> less_le
   577   zpower_zadd_distrib ~> power_add
   578   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   579   zero_le_zpower_abs ~> zero_le_power_abs
   580 
   581 * Theory Deriv: Renamed
   582 
   583   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   584 
   585 * New "case_product" attribute to generate a case rule doing multiple
   586 case distinctions at the same time.  E.g.
   587 
   588   list.exhaust [case_product nat.exhaust]
   589 
   590 produces a rule which can be used to perform case distinction on both
   591 a list and a nat.
   592 
   593 * Theory Library/Multiset: Improved code generation of multisets.
   594 
   595 * New diagnostic command 'find_unused_assms' to find potentially
   596 superfluous assumptions in theorems using Quickcheck.
   597 
   598 * Quickcheck:
   599 
   600   - Quickcheck returns variable assignments as counterexamples, which
   601     allows to reveal the underspecification of functions under test.
   602     For example, refuting "hd xs = x", it presents the variable
   603     assignment xs = [] and x = a1 as a counterexample, assuming that
   604     any property is false whenever "hd []" occurs in it.
   605 
   606     These counterexample are marked as potentially spurious, as
   607     Quickcheck also returns "xs = []" as a counterexample to the
   608     obvious theorem "hd xs = hd xs".
   609 
   610     After finding a potentially spurious counterexample, Quickcheck
   611     continues searching for genuine ones.
   612 
   613     By default, Quickcheck shows potentially spurious and genuine
   614     counterexamples. The option "genuine_only" sets quickcheck to only
   615     show genuine counterexamples.
   616 
   617   - The command 'quickcheck_generator' creates random and exhaustive
   618     value generators for a given type and operations.
   619 
   620     It generates values by using the operations as if they were
   621     constructors of that type.
   622 
   623   - Support for multisets.
   624 
   625   - Added "use_subtype" options.
   626 
   627   - Added "quickcheck_locale" configuration to specify how to process
   628     conjectures in a locale context.
   629 
   630 * Nitpick:
   631 
   632   - Fixed infinite loop caused by the 'peephole_optim' option and
   633     affecting 'rat' and 'real'.
   634 
   635 * Sledgehammer:
   636   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   637   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   638   - Renamed "sound" option to "strict".
   639 
   640 * Metis:
   641   - Added possibility to specify lambda translations scheme as a
   642     parenthesized argument (e.g., "by (metis (lifting) ...)").
   643 
   644 * SMT:
   645   - renamed "smt_fixed" option to "smt_read_only_certificates".
   646 
   647 * Command 'try0':
   648   - Renamed from 'try_methods'. INCOMPATIBILITY.
   649 
   650 * New "eventually_elim" method as a generalized variant of the
   651 eventually_elim* rules. Supports structured proofs.
   652 
   653 * HOL/TPTP: support to parse and import TPTP problems (all languages)
   654 into Isabelle/HOL.
   655 
   656 
   657 *** FOL ***
   658 
   659 * New "case_product" attribute (see HOL).
   660 
   661 
   662 *** ZF ***
   663 
   664 * Greater support for structured proofs involving induction or case
   665 analysis.
   666 
   667 * Much greater use of mathematical symbols.
   668 
   669 * Removal of many ML theorem bindings.  INCOMPATIBILITY.
   670 
   671 
   672 *** ML ***
   673 
   674 * Antiquotation @{keyword "name"} produces a parser for outer syntax
   675 from a minor keyword introduced via theory header declaration.
   676 
   677 * Antiquotation @{command_spec "name"} produces the
   678 Outer_Syntax.command_spec from a major keyword introduced via theory
   679 header declaration; it can be passed to Outer_Syntax.command etc.
   680 
   681 * Local_Theory.define no longer hard-wires default theorem name
   682 "foo_def", but retains the binding as given.  If that is Binding.empty
   683 / Attrib.empty_binding, the result is not registered as user-level
   684 fact.  The Local_Theory.define_internal variant allows to specify a
   685 non-empty name (used for the foundation in the background theory),
   686 while omitting the fact binding in the user-context.  Potential
   687 INCOMPATIBILITY for derived definitional packages: need to specify
   688 naming policy for primitive definitions more explicitly.
   689 
   690 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
   691 conformance with similar operations in structure Term and Logic.
   692 
   693 * Antiquotation @{attributes [...]} embeds attribute source
   694 representation into the ML text, which is particularly useful with
   695 declarations like Local_Theory.note.
   696 
   697 * Structure Proof_Context follows standard naming scheme.  Old
   698 ProofContext has been discontinued.  INCOMPATIBILITY.
   699 
   700 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   701 change of semantics: update is applied to auxiliary local theory
   702 context as well.
   703 
   704 * Modernized some old-style infix operations:
   705 
   706   addeqcongs    ~> Simplifier.add_eqcong
   707   deleqcongs    ~> Simplifier.del_eqcong
   708   addcongs      ~> Simplifier.add_cong
   709   delcongs      ~> Simplifier.del_cong
   710   setmksimps    ~> Simplifier.set_mksimps
   711   setmkcong     ~> Simplifier.set_mkcong
   712   setmksym      ~> Simplifier.set_mksym
   713   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   714   settermless   ~> Simplifier.set_termless
   715   setsubgoaler  ~> Simplifier.set_subgoaler
   716   addsplits     ~> Splitter.add_split
   717   delsplits     ~> Splitter.del_split
   718 
   719 
   720 *** System ***
   721 
   722 * ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
   723 (not just JRE).
   724 
   725 * ISABELLE_HOME_WINDOWS refers to ISABELLE_HOME in windows file name
   726 notation, which is useful for the jEdit file browser, for example.
   727 
   728 
   729 
   730 New in Isabelle2011-1 (October 2011)
   731 ------------------------------------
   732 
   733 *** General ***
   734 
   735 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   736 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   737 
   738   - Management of multiple theory files directly from the editor
   739     buffer store -- bypassing the file-system (no requirement to save
   740     files for checking).
   741 
   742   - Markup of formal entities within the text buffer, with semantic
   743     highlighting, tooltips and hyperlinks to jump to defining source
   744     positions.
   745 
   746   - Improved text rendering, with sub/superscripts in the source
   747     buffer (including support for copy/paste wrt. output panel, HTML
   748     theory output and other non-Isabelle text boxes).
   749 
   750   - Refined scheduling of proof checking and printing of results,
   751     based on interactive editor view.  (Note: jEdit folding and
   752     narrowing allows to restrict buffer perspectives explicitly.)
   753 
   754   - Reduced CPU performance requirements, usable on machines with few
   755     cores.
   756 
   757   - Reduced memory requirements due to pruning of unused document
   758     versions (garbage collection).
   759 
   760 See also ~~/src/Tools/jEdit/README.html for further information,
   761 including some remaining limitations.
   762 
   763 * Theory loader: source files are exclusively located via the master
   764 directory of each theory node (where the .thy file itself resides).
   765 The global load path (such as src/HOL/Library) has been discontinued.
   766 Note that the path element ~~ may be used to reference theories in the
   767 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   768 INCOMPATIBILITY.
   769 
   770 * Theory loader: source files are identified by content via SHA1
   771 digests.  Discontinued former path/modtime identification and optional
   772 ISABELLE_FILE_IDENT plugin scripts.
   773 
   774 * Parallelization of nested Isar proofs is subject to
   775 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   776 usedir option -Q.
   777 
   778 * Name space: former unsynchronized references are now proper
   779 configuration options, with more conventional names:
   780 
   781   long_names   ~> names_long
   782   short_names  ~> names_short
   783   unique_names ~> names_unique
   784 
   785 Minor INCOMPATIBILITY, need to declare options in context like this:
   786 
   787   declare [[names_unique = false]]
   788 
   789 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   790 that the result needs to be unique, which means fact specifications
   791 may have to be refined after enriching a proof context.
   792 
   793 * Attribute "case_names" has been refined: the assumptions in each case
   794 can be named now by following the case name with [name1 name2 ...].
   795 
   796 * Isabelle/Isar reference manual has been updated and extended:
   797   - "Synopsis" provides a catalog of main Isar language concepts.
   798   - Formal references in syntax diagrams, via @{rail} antiquotation.
   799   - Updated material from classic "ref" manual, notably about
   800     "Classical Reasoner".
   801 
   802 
   803 *** HOL ***
   804 
   805 * Class bot and top require underlying partial order rather than
   806 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   807 
   808 * Class complete_lattice: generalized a couple of lemmas from sets;
   809 generalized theorems INF_cong and SUP_cong.  New type classes for
   810 complete boolean algebras and complete linear orders.  Lemmas
   811 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   812 class complete_linorder.
   813 
   814 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   815 Sup_fun_def, Inf_apply, Sup_apply.
   816 
   817 Removed redundant lemmas (the right hand side gives hints how to
   818 replace them for (metis ...), or (simp only: ...) proofs):
   819 
   820   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   821   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   822   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   823   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   824   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   825   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   826   Inter_def ~> INF_def, image_def
   827   Union_def ~> SUP_def, image_def
   828   INT_eq ~> INF_def, and image_def
   829   UN_eq ~> SUP_def, and image_def
   830   INF_subset ~> INF_superset_mono [OF _ order_refl]
   831 
   832 More consistent and comprehensive names:
   833 
   834   INTER_eq_Inter_image ~> INF_def
   835   UNION_eq_Union_image ~> SUP_def
   836   INFI_def ~> INF_def
   837   SUPR_def ~> SUP_def
   838   INF_leI ~> INF_lower
   839   INF_leI2 ~> INF_lower2
   840   le_INFI ~> INF_greatest
   841   le_SUPI ~> SUP_upper
   842   le_SUPI2 ~> SUP_upper2
   843   SUP_leI ~> SUP_least
   844   INFI_bool_eq ~> INF_bool_eq
   845   SUPR_bool_eq ~> SUP_bool_eq
   846   INFI_apply ~> INF_apply
   847   SUPR_apply ~> SUP_apply
   848   INTER_def ~> INTER_eq
   849   UNION_def ~> UNION_eq
   850 
   851 INCOMPATIBILITY.
   852 
   853 * Renamed theory Complete_Lattice to Complete_Lattices.
   854 INCOMPATIBILITY.
   855 
   856 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   857 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   858 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   859 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   860 
   861 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   862 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   863 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   864 INCOMPATIBILITY.
   865 
   866 * Added syntactic classes "inf" and "sup" for the respective
   867 constants.  INCOMPATIBILITY: Changes in the argument order of the
   868 (mostly internal) locale predicates for some derived classes.
   869 
   870 * Theorem collections ball_simps and bex_simps do not contain theorems
   871 referring to UNION any longer; these have been moved to collection
   872 UN_ball_bex_simps.  INCOMPATIBILITY.
   873 
   874 * Theory Archimedean_Field: floor now is defined as parameter of a
   875 separate type class floor_ceiling.
   876 
   877 * Theory Finite_Set: more coherent development of fold_set locales:
   878 
   879     locale fun_left_comm ~> locale comp_fun_commute
   880     locale fun_left_comm_idem ~> locale comp_fun_idem
   881 
   882 Both use point-free characterization; interpretation proofs may need
   883 adjustment.  INCOMPATIBILITY.
   884 
   885 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   886 accordance with standard mathematical terminology. INCOMPATIBILITY.
   887 
   888 * Theory Complex_Main: The locale interpretations for the
   889 bounded_linear and bounded_bilinear locales have been removed, in
   890 order to reduce the number of duplicate lemmas. Users must use the
   891 original names for distributivity theorems, potential INCOMPATIBILITY.
   892 
   893   divide.add ~> add_divide_distrib
   894   divide.diff ~> diff_divide_distrib
   895   divide.setsum ~> setsum_divide_distrib
   896   mult.add_right ~> right_distrib
   897   mult.diff_right ~> right_diff_distrib
   898   mult_right.setsum ~> setsum_right_distrib
   899   mult_left.diff ~> left_diff_distrib
   900 
   901 * Theory Complex_Main: Several redundant theorems have been removed or
   902 replaced by more general versions. INCOMPATIBILITY.
   903 
   904   real_diff_def ~> minus_real_def
   905   real_divide_def ~> divide_real_def
   906   real_less_def ~> less_le
   907   real_abs_def ~> abs_real_def
   908   real_sgn_def ~> sgn_real_def
   909   real_mult_commute ~> mult_commute
   910   real_mult_assoc ~> mult_assoc
   911   real_mult_1 ~> mult_1_left
   912   real_add_mult_distrib ~> left_distrib
   913   real_zero_not_eq_one ~> zero_neq_one
   914   real_mult_inverse_left ~> left_inverse
   915   INVERSE_ZERO ~> inverse_zero
   916   real_le_refl ~> order_refl
   917   real_le_antisym ~> order_antisym
   918   real_le_trans ~> order_trans
   919   real_le_linear ~> linear
   920   real_le_eq_diff ~> le_iff_diff_le_0
   921   real_add_left_mono ~> add_left_mono
   922   real_mult_order ~> mult_pos_pos
   923   real_mult_less_mono2 ~> mult_strict_left_mono
   924   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   925   real_0_le_divide_iff ~> zero_le_divide_iff
   926   realpow_two_disj ~> power2_eq_iff
   927   real_squared_diff_one_factored ~> square_diff_one_factored
   928   realpow_two_diff ~> square_diff_square_factored
   929   reals_complete2 ~> complete_real
   930   real_sum_squared_expand ~> power2_sum
   931   exp_ln_eq ~> ln_unique
   932   expi_add ~> exp_add
   933   expi_zero ~> exp_zero
   934   lemma_DERIV_subst ~> DERIV_cong
   935   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   936   LIMSEQ_const ~> tendsto_const
   937   LIMSEQ_norm ~> tendsto_norm
   938   LIMSEQ_add ~> tendsto_add
   939   LIMSEQ_minus ~> tendsto_minus
   940   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   941   LIMSEQ_diff ~> tendsto_diff
   942   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   943   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   944   LIMSEQ_mult ~> tendsto_mult
   945   LIMSEQ_inverse ~> tendsto_inverse
   946   LIMSEQ_divide ~> tendsto_divide
   947   LIMSEQ_pow ~> tendsto_power
   948   LIMSEQ_setsum ~> tendsto_setsum
   949   LIMSEQ_setprod ~> tendsto_setprod
   950   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   951   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   952   LIMSEQ_imp_rabs ~> tendsto_rabs
   953   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   954   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   955   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   956   LIMSEQ_Complex ~> tendsto_Complex
   957   LIM_ident ~> tendsto_ident_at
   958   LIM_const ~> tendsto_const
   959   LIM_add ~> tendsto_add
   960   LIM_add_zero ~> tendsto_add_zero
   961   LIM_minus ~> tendsto_minus
   962   LIM_diff ~> tendsto_diff
   963   LIM_norm ~> tendsto_norm
   964   LIM_norm_zero ~> tendsto_norm_zero
   965   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   966   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   967   LIM_rabs ~> tendsto_rabs
   968   LIM_rabs_zero ~> tendsto_rabs_zero
   969   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   970   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   971   LIM_compose ~> tendsto_compose
   972   LIM_mult ~> tendsto_mult
   973   LIM_scaleR ~> tendsto_scaleR
   974   LIM_of_real ~> tendsto_of_real
   975   LIM_power ~> tendsto_power
   976   LIM_inverse ~> tendsto_inverse
   977   LIM_sgn ~> tendsto_sgn
   978   isCont_LIM_compose ~> isCont_tendsto_compose
   979   bounded_linear.LIM ~> bounded_linear.tendsto
   980   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   981   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   982   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   983   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   984   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   985   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   986 
   987 * Theory Complex_Main: The definition of infinite series was
   988 generalized.  Now it is defined on the type class {topological_space,
   989 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   990 
   991 * Theory Complex_Main: The complex exponential function "expi" is now
   992 a type-constrained abbreviation for "exp :: complex => complex"; thus
   993 several polymorphic lemmas about "exp" are now applicable to "expi".
   994 
   995 * Code generation:
   996 
   997   - Theory Library/Code_Char_ord provides native ordering of
   998     characters in the target language.
   999 
  1000   - Commands code_module and code_library are legacy, use export_code
  1001     instead.
  1002 
  1003   - Method "evaluation" is legacy, use method "eval" instead.
  1004 
  1005   - Legacy evaluator "SML" is deactivated by default.  May be
  1006     reactivated by the following theory command:
  1007 
  1008       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
  1009 
  1010 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
  1011 
  1012 * New proof method "induction" that gives induction hypotheses the
  1013 name "IH", thus distinguishing them from further hypotheses that come
  1014 from rule induction.  The latter are still called "hyps".  Method
  1015 "induction" is a thin wrapper around "induct" and follows the same
  1016 syntax.
  1017 
  1018 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
  1019 still available as a legacy feature for some time.
  1020 
  1021 * Nitpick:
  1022   - Added "need" and "total_consts" options.
  1023   - Reintroduced "show_skolems" option by popular demand.
  1024   - Renamed attribute: nitpick_def ~> nitpick_unfold.
  1025     INCOMPATIBILITY.
  1026 
  1027 * Sledgehammer:
  1028   - Use quasi-sound (and efficient) translations by default.
  1029   - Added support for the following provers: E-ToFoF, LEO-II,
  1030     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
  1031   - Automatically preplay and minimize proofs before showing them if
  1032     this can be done within reasonable time.
  1033   - sledgehammer available_provers ~> sledgehammer supported_provers.
  1034     INCOMPATIBILITY.
  1035   - Added "preplay_timeout", "slicing", "type_enc", "sound",
  1036     "max_mono_iters", and "max_new_mono_instances" options.
  1037   - Removed "explicit_apply" and "full_types" options as well as "Full
  1038     Types" Proof General menu item. INCOMPATIBILITY.
  1039 
  1040 * Metis:
  1041   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
  1042   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
  1043     INCOMPATIBILITY.
  1044 
  1045 * Command 'try':
  1046   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
  1047     "elim:" options. INCOMPATIBILITY.
  1048   - Introduced 'try' that not only runs 'try_methods' but also
  1049     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
  1050 
  1051 * Quickcheck:
  1052   - Added "eval" option to evaluate terms for the found counterexample
  1053     (currently only supported by the default (exhaustive) tester).
  1054   - Added post-processing of terms to obtain readable counterexamples
  1055     (currently only supported by the default (exhaustive) tester).
  1056   - New counterexample generator quickcheck[narrowing] enables
  1057     narrowing-based testing.  Requires the Glasgow Haskell compiler
  1058     with its installation location defined in the Isabelle settings
  1059     environment as ISABELLE_GHC.
  1060   - Removed quickcheck tester "SML" based on the SML code generator
  1061     (formly in HOL/Library).
  1062 
  1063 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
  1064 use 'partial_function' instead.
  1065 
  1066 * Theory Library/Extended_Reals replaces now the positive extended
  1067 reals found in probability theory. This file is extended by
  1068 Multivariate_Analysis/Extended_Real_Limits.
  1069 
  1070 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
  1071 from where it must be imported explicitly if it is really required.
  1072 INCOMPATIBILITY.
  1073 
  1074 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
  1075 been moved here.  INCOMPATIBILITY.
  1076 
  1077 * Theory Library/Saturated provides type of numbers with saturated
  1078 arithmetic.
  1079 
  1080 * Theory Library/Product_Lattice defines a pointwise ordering for the
  1081 product type 'a * 'b, and provides instance proofs for various order
  1082 and lattice type classes.
  1083 
  1084 * Theory Library/Countable now provides the "countable_datatype" proof
  1085 method for proving "countable" class instances for datatypes.
  1086 
  1087 * Theory Library/Cset_Monad allows do notation for computable sets
  1088 (cset) via the generic monad ad-hoc overloading facility.
  1089 
  1090 * Library: Theories of common data structures are split into theories
  1091 for implementation, an invariant-ensuring type, and connection to an
  1092 abstract type. INCOMPATIBILITY.
  1093 
  1094   - RBT is split into RBT and RBT_Mapping.
  1095   - AssocList is split and renamed into AList and AList_Mapping.
  1096   - DList is split into DList_Impl, DList, and DList_Cset.
  1097   - Cset is split into Cset and List_Cset.
  1098 
  1099 * Theory Library/Nat_Infinity has been renamed to
  1100 Library/Extended_Nat, with name changes of the following types and
  1101 constants:
  1102 
  1103   type inat   ~> type enat
  1104   Fin         ~> enat
  1105   Infty       ~> infinity (overloaded)
  1106   iSuc        ~> eSuc
  1107   the_Fin     ~> the_enat
  1108 
  1109 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
  1110 been renamed accordingly. INCOMPATIBILITY.
  1111 
  1112 * Session Multivariate_Analysis: The euclidean_space type class now
  1113 fixes a constant "Basis :: 'a set" consisting of the standard
  1114 orthonormal basis for the type. Users now have the option of
  1115 quantifying over this set instead of using the "basis" function, e.g.
  1116 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
  1117 
  1118 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
  1119 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
  1120 "Cart_nth" and "Cart_lambda" have been respectively renamed to
  1121 "vec_nth" and "vec_lambda"; theorems mentioning those names have
  1122 changed to match. Definition theorems for overloaded constants now use
  1123 the standard "foo_vec_def" naming scheme. A few other theorems have
  1124 been renamed as follows (INCOMPATIBILITY):
  1125 
  1126   Cart_eq          ~> vec_eq_iff
  1127   dist_nth_le_cart ~> dist_vec_nth_le
  1128   tendsto_vector   ~> vec_tendstoI
  1129   Cauchy_vector    ~> vec_CauchyI
  1130 
  1131 * Session Multivariate_Analysis: Several duplicate theorems have been
  1132 removed, and other theorems have been renamed or replaced with more
  1133 general versions. INCOMPATIBILITY.
  1134 
  1135   finite_choice ~> finite_set_choice
  1136   eventually_conjI ~> eventually_conj
  1137   eventually_and ~> eventually_conj_iff
  1138   eventually_false ~> eventually_False
  1139   setsum_norm ~> norm_setsum
  1140   Lim_sequentially ~> LIMSEQ_def
  1141   Lim_ident_at ~> LIM_ident
  1142   Lim_const ~> tendsto_const
  1143   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
  1144   Lim_neg ~> tendsto_minus
  1145   Lim_add ~> tendsto_add
  1146   Lim_sub ~> tendsto_diff
  1147   Lim_mul ~> tendsto_scaleR
  1148   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
  1149   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
  1150   Lim_linear ~> bounded_linear.tendsto
  1151   Lim_component ~> tendsto_euclidean_component
  1152   Lim_component_cart ~> tendsto_vec_nth
  1153   Lim_inner ~> tendsto_inner [OF tendsto_const]
  1154   dot_lsum ~> inner_setsum_left
  1155   dot_rsum ~> inner_setsum_right
  1156   continuous_cmul ~> continuous_scaleR [OF continuous_const]
  1157   continuous_neg ~> continuous_minus
  1158   continuous_sub ~> continuous_diff
  1159   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
  1160   continuous_mul ~> continuous_scaleR
  1161   continuous_inv ~> continuous_inverse
  1162   continuous_at_within_inv ~> continuous_at_within_inverse
  1163   continuous_at_inv ~> continuous_at_inverse
  1164   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
  1165   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
  1166   continuous_at_component ~> continuous_component [OF continuous_at_id]
  1167   continuous_on_neg ~> continuous_on_minus
  1168   continuous_on_sub ~> continuous_on_diff
  1169   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
  1170   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
  1171   continuous_on_mul ~> continuous_on_scaleR
  1172   continuous_on_mul_real ~> continuous_on_mult
  1173   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
  1174   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
  1175   continuous_on_inverse ~> continuous_on_inv
  1176   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
  1177   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
  1178   subset_interior ~> interior_mono
  1179   subset_closure ~> closure_mono
  1180   closure_univ ~> closure_UNIV
  1181   real_arch_lt ~> reals_Archimedean2
  1182   real_arch ~> reals_Archimedean3
  1183   real_abs_norm ~> abs_norm_cancel
  1184   real_abs_sub_norm ~> norm_triangle_ineq3
  1185   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
  1186 
  1187 * Session HOL-Probability:
  1188   - Caratheodory's extension lemma is now proved for ring_of_sets.
  1189   - Infinite products of probability measures are now available.
  1190   - Sigma closure is independent, if the generator is independent
  1191   - Use extended reals instead of positive extended
  1192     reals. INCOMPATIBILITY.
  1193 
  1194 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
  1195 
  1196   expand_fun_below ~> fun_below_iff
  1197   below_fun_ext ~> fun_belowI
  1198   expand_cfun_eq ~> cfun_eq_iff
  1199   ext_cfun ~> cfun_eqI
  1200   expand_cfun_below ~> cfun_below_iff
  1201   below_cfun_ext ~> cfun_belowI
  1202   monofun_fun_fun ~> fun_belowD
  1203   monofun_fun_arg ~> monofunE
  1204   monofun_lub_fun ~> adm_monofun [THEN admD]
  1205   cont_lub_fun ~> adm_cont [THEN admD]
  1206   cont2cont_Rep_CFun ~> cont2cont_APP
  1207   cont_Rep_CFun_app ~> cont_APP_app
  1208   cont_Rep_CFun_app_app ~> cont_APP_app_app
  1209   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
  1210   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
  1211   contlub_cfun ~> lub_APP [symmetric]
  1212   contlub_LAM ~> lub_LAM [symmetric]
  1213   thelubI ~> lub_eqI
  1214   UU_I ~> bottomI
  1215   lift_distinct1 ~> lift.distinct(1)
  1216   lift_distinct2 ~> lift.distinct(2)
  1217   Def_not_UU ~> lift.distinct(2)
  1218   Def_inject ~> lift.inject
  1219   below_UU_iff ~> below_bottom_iff
  1220   eq_UU_iff ~> eq_bottom_iff
  1221 
  1222 
  1223 *** Document preparation ***
  1224 
  1225 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
  1226 isar-ref manual, both for description and actual application of the
  1227 same.
  1228 
  1229 * Antiquotation @{value} evaluates the given term and presents its
  1230 result.
  1231 
  1232 * Antiquotations: term style "isub" provides ad-hoc conversion of
  1233 variables x1, y23 into subscripted form x\<^isub>1,
  1234 y\<^isub>2\<^isub>3.
  1235 
  1236 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
  1237 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
  1238 
  1239 * Localized \isabellestyle switch can be used within blocks or groups
  1240 like this:
  1241 
  1242   \isabellestyle{it}  %preferred default
  1243   {\isabellestylett @{text "typewriter stuff"}}
  1244 
  1245 * Discontinued special treatment of hard tabulators.  Implicit
  1246 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
  1247 layouts.
  1248 
  1249 
  1250 *** ML ***
  1251 
  1252 * The inner syntax of sort/type/term/prop supports inlined YXML
  1253 representations within quoted string tokens.  By encoding logical
  1254 entities via Term_XML (in ML or Scala) concrete syntax can be
  1255 bypassed, which is particularly useful for producing bits of text
  1256 under external program control.
  1257 
  1258 * Antiquotations for ML and document preparation are managed as theory
  1259 data, which requires explicit setup.
  1260 
  1261 * Isabelle_Process.is_active allows tools to check if the official
  1262 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
  1263 (better known as Proof General).
  1264 
  1265 * Structure Proof_Context follows standard naming scheme.  Old
  1266 ProofContext is still available for some time as legacy alias.
  1267 
  1268 * Structure Timing provides various operations for timing; supersedes
  1269 former start_timing/end_timing etc.
  1270 
  1271 * Path.print is the official way to show file-system paths to users
  1272 (including quotes etc.).
  1273 
  1274 * Inner syntax: identifiers in parse trees of generic categories
  1275 "logic", "aprop", "idt" etc. carry position information (disguised as
  1276 type constraints).  Occasional INCOMPATIBILITY with non-compliant
  1277 translations that choke on unexpected type constraints.  Positions can
  1278 be stripped in ML translations via Syntax.strip_positions /
  1279 Syntax.strip_positions_ast, or via the syntax constant
  1280 "_strip_positions" within parse trees.  As last resort, positions can
  1281 be disabled via the configuration option Syntax.positions, which is
  1282 called "syntax_positions" in Isar attribute syntax.
  1283 
  1284 * Discontinued special status of various ML structures that contribute
  1285 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
  1286 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
  1287 refer directly to Ast.Constant, Lexicon.is_identifier,
  1288 Syntax_Trans.mk_binder_tr etc.
  1289 
  1290 * Typed print translation: discontinued show_sorts argument, which is
  1291 already available via context of "advanced" translation.
  1292 
  1293 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
  1294 goal states; body tactic needs to address all subgoals uniformly.
  1295 
  1296 * Slightly more special eq_list/eq_set, with shortcut involving
  1297 pointer equality (assumes that eq relation is reflexive).
  1298 
  1299 * Classical tactics use proper Proof.context instead of historic types
  1300 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  1301 operate directly on Proof.context.  Raw type claset retains its use as
  1302 snapshot of the classical context, which can be recovered via
  1303 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  1304 INCOMPATIBILITY, classical tactics and derived proof methods require
  1305 proper Proof.context.
  1306 
  1307 
  1308 *** System ***
  1309 
  1310 * Discontinued support for Poly/ML 5.2, which was the last version
  1311 without proper multithreading and TimeLimit implementation.
  1312 
  1313 * Discontinued old lib/scripts/polyml-platform, which has been
  1314 obsolete since Isabelle2009-2.
  1315 
  1316 * Various optional external tools are referenced more robustly and
  1317 uniformly by explicit Isabelle settings as follows:
  1318 
  1319   ISABELLE_CSDP   (formerly CSDP_EXE)
  1320   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  1321   ISABELLE_OCAML  (formerly EXEC_OCAML)
  1322   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  1323   ISABELLE_YAP    (formerly EXEC_YAP)
  1324 
  1325 Note that automated detection from the file-system or search path has
  1326 been discontinued.  INCOMPATIBILITY.
  1327 
  1328 * Scala layer provides JVM method invocation service for static
  1329 methods of type (String)String, see Invoke_Scala.method in ML.  For
  1330 example:
  1331 
  1332   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  1333 
  1334 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  1335 this allows to pass structured values between ML and Scala.
  1336 
  1337 * The IsabelleText fonts includes some further glyphs to support the
  1338 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  1339 installed a local copy (which is normally *not* required) need to
  1340 delete or update it from ~~/lib/fonts/.
  1341 
  1342 
  1343 
  1344 New in Isabelle2011 (January 2011)
  1345 ----------------------------------
  1346 
  1347 *** General ***
  1348 
  1349 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  1350 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  1351 useful tooltips and hyperlinks produced from its static analysis.  The
  1352 bundled component provides an executable Isabelle tool that can be run
  1353 like this:
  1354 
  1355   Isabelle2011/bin/isabelle jedit
  1356 
  1357 * Significantly improved Isabelle/Isar implementation manual.
  1358 
  1359 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  1360 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  1361 while the default heap location within that directory lacks that extra
  1362 suffix.  This isolates multiple Isabelle installations from each
  1363 other, avoiding problems with old settings in new versions.
  1364 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  1365 
  1366 * Source files are always encoded as UTF-8, instead of old-fashioned
  1367 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  1368 the following package declarations:
  1369 
  1370   \usepackage[utf8]{inputenc}
  1371   \usepackage{textcomp}
  1372 
  1373 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  1374 a Unicode character is treated as a single symbol, not a sequence of
  1375 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  1376 contain symbols without further backslash escapes, Unicode can now be
  1377 used here as well.  Recall that Symbol.explode in ML provides a
  1378 consistent view on symbols, while raw explode (or String.explode)
  1379 merely give a byte-oriented representation.
  1380 
  1381 * Theory loader: source files are primarily located via the master
  1382 directory of each theory node (where the .thy file itself resides).
  1383 The global load path is still partially available as legacy feature.
  1384 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  1385 explicit paths, relatively to the theory.
  1386 
  1387 * Special treatment of ML file names has been discontinued.
  1388 Historically, optional extensions .ML or .sml were added on demand --
  1389 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  1390 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  1391 
  1392 * Various options that affect pretty printing etc. are now properly
  1393 handled within the context via configuration options, instead of
  1394 unsynchronized references or print modes.  There are both ML Config.T
  1395 entities and Isar declaration attributes to access these.
  1396 
  1397   ML (Config.T)                 Isar (attribute)
  1398 
  1399   eta_contract                  eta_contract
  1400   show_brackets                 show_brackets
  1401   show_sorts                    show_sorts
  1402   show_types                    show_types
  1403   show_question_marks           show_question_marks
  1404   show_consts                   show_consts
  1405   show_abbrevs                  show_abbrevs
  1406 
  1407   Syntax.ast_trace              syntax_ast_trace
  1408   Syntax.ast_stat               syntax_ast_stat
  1409   Syntax.ambiguity_level        syntax_ambiguity_level
  1410 
  1411   Goal_Display.goals_limit      goals_limit
  1412   Goal_Display.show_main_goal   show_main_goal
  1413 
  1414   Method.rule_trace             rule_trace
  1415 
  1416   Thy_Output.display            thy_output_display
  1417   Thy_Output.quotes             thy_output_quotes
  1418   Thy_Output.indent             thy_output_indent
  1419   Thy_Output.source             thy_output_source
  1420   Thy_Output.break              thy_output_break
  1421 
  1422 Note that corresponding "..._default" references in ML may only be
  1423 changed globally at the ROOT session setup, but *not* within a theory.
  1424 The option "show_abbrevs" supersedes the former print mode
  1425 "no_abbrevs" with inverted meaning.
  1426 
  1427 * More systematic naming of some configuration options.
  1428 INCOMPATIBILITY.
  1429 
  1430   trace_simp  ~>  simp_trace
  1431   debug_simp  ~>  simp_debug
  1432 
  1433 * Support for real valued configuration options, using simplistic
  1434 floating-point notation that coincides with the inner syntax for
  1435 float_token.
  1436 
  1437 * Support for real valued preferences (with approximative PGIP type):
  1438 front-ends need to accept "pgint" values in float notation.
  1439 INCOMPATIBILITY.
  1440 
  1441 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  1442 DejaVu Sans.
  1443 
  1444 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  1445 
  1446 
  1447 *** Pure ***
  1448 
  1449 * Command 'type_synonym' (with single argument) replaces somewhat
  1450 outdated 'types', which is still available as legacy feature for some
  1451 time.
  1452 
  1453 * Command 'nonterminal' (with 'and' separated list of arguments)
  1454 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  1455 
  1456 * Command 'notepad' replaces former 'example_proof' for
  1457 experimentation in Isar without any result.  INCOMPATIBILITY.
  1458 
  1459 * Locale interpretation commands 'interpret' and 'sublocale' accept
  1460 lists of equations to map definitions in a locale to appropriate
  1461 entities in the context of the interpretation.  The 'interpretation'
  1462 command already provided this functionality.
  1463 
  1464 * Diagnostic command 'print_dependencies' prints the locale instances
  1465 that would be activated if the specified expression was interpreted in
  1466 the current context.  Variant "print_dependencies!" assumes a context
  1467 without interpretations.
  1468 
  1469 * Diagnostic command 'print_interps' prints interpretations in proofs
  1470 in addition to interpretations in theories.
  1471 
  1472 * Discontinued obsolete 'global' and 'local' commands to manipulate
  1473 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  1474 Sign.root_path and Sign.local_path may be applied directly where this
  1475 feature is still required for historical reasons.
  1476 
  1477 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  1478 'definition' instead.
  1479 
  1480 * The "prems" fact, which refers to the accidental collection of
  1481 foundational premises in the context, is now explicitly marked as
  1482 legacy feature and will be discontinued soon.  Consider using "assms"
  1483 of the head statement or reference facts by explicit names.
  1484 
  1485 * Document antiquotations @{class} and @{type} print classes and type
  1486 constructors.
  1487 
  1488 * Document antiquotation @{file} checks file/directory entries within
  1489 the local file system.
  1490 
  1491 
  1492 *** HOL ***
  1493 
  1494 * Coercive subtyping: functions can be declared as coercions and type
  1495 inference will add them as necessary upon input of a term.  Theory
  1496 Complex_Main declares real :: nat => real and real :: int => real as
  1497 coercions. A coercion function f is declared like this:
  1498 
  1499   declare [[coercion f]]
  1500 
  1501 To lift coercions through type constructors (e.g. from nat => real to
  1502 nat list => real list), map functions can be declared, e.g.
  1503 
  1504   declare [[coercion_map map]]
  1505 
  1506 Currently coercion inference is activated only in theories including
  1507 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1508 the configuration option "coercion_enabled", e.g. it can be enabled in
  1509 other theories like this:
  1510 
  1511   declare [[coercion_enabled]]
  1512 
  1513 * Command 'partial_function' provides basic support for recursive
  1514 function definitions over complete partial orders.  Concrete instances
  1515 are provided for i) the option type, ii) tail recursion on arbitrary
  1516 types, and iii) the heap monad of Imperative_HOL.  See
  1517 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1518 for examples.
  1519 
  1520 * Function package: f.psimps rules are no longer implicitly declared
  1521 as [simp].  INCOMPATIBILITY.
  1522 
  1523 * Datatype package: theorems generated for executable equality (class
  1524 "eq") carry proper names and are treated as default code equations.
  1525 
  1526 * Inductive package: now offers command 'inductive_simps' to
  1527 automatically derive instantiated and simplified equations for
  1528 inductive predicates, similar to 'inductive_cases'.
  1529 
  1530 * Command 'enriched_type' allows to register properties of the
  1531 functorial structure of types.
  1532 
  1533 * Improved infrastructure for term evaluation using code generator
  1534 techniques, in particular static evaluation conversions.
  1535 
  1536 * Code generator: Scala (2.8 or higher) has been added to the target
  1537 languages.
  1538 
  1539 * Code generator: globbing constant expressions "*" and "Theory.*"
  1540 have been replaced by the more idiomatic "_" and "Theory._".
  1541 INCOMPATIBILITY.
  1542 
  1543 * Code generator: export_code without explicit file declaration prints
  1544 to standard output.  INCOMPATIBILITY.
  1545 
  1546 * Code generator: do not print function definitions for case
  1547 combinators any longer.
  1548 
  1549 * Code generator: simplification with rules determined with
  1550 src/Tools/Code/code_simp.ML and method "code_simp".
  1551 
  1552 * Code generator for records: more idiomatic representation of record
  1553 types.  Warning: records are not covered by ancient SML code
  1554 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1555 rep_datatype declaration helps to succeed then:
  1556 
  1557   record 'a foo = ...
  1558   ...
  1559   rep_datatype foo_ext ...
  1560 
  1561 * Records: logical foundation type for records does not carry a
  1562 '_type' suffix any longer (obsolete due to authentic syntax).
  1563 INCOMPATIBILITY.
  1564 
  1565 * Quickcheck now by default uses exhaustive testing instead of random
  1566 testing.  Random testing can be invoked by "quickcheck [random]",
  1567 exhaustive testing by "quickcheck [exhaustive]".
  1568 
  1569 * Quickcheck instantiates polymorphic types with small finite
  1570 datatypes by default. This enables a simple execution mechanism to
  1571 handle quantifiers and function equality over the finite datatypes.
  1572 
  1573 * Quickcheck random generator has been renamed from "code" to
  1574 "random".  INCOMPATIBILITY.
  1575 
  1576 * Quickcheck now has a configurable time limit which is set to 30
  1577 seconds by default. This can be changed by adding [timeout = n] to the
  1578 quickcheck command. The time limit for Auto Quickcheck is still set
  1579 independently.
  1580 
  1581 * Quickcheck in locales considers interpretations of that locale for
  1582 counter example search.
  1583 
  1584 * Sledgehammer:
  1585   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1586     method. See the Sledgehammer manual for details ("isabelle doc
  1587     sledgehammer").
  1588   - Renamed commands:
  1589     sledgehammer atp_info ~> sledgehammer running_provers
  1590     sledgehammer atp_kill ~> sledgehammer kill_provers
  1591     sledgehammer available_atps ~> sledgehammer available_provers
  1592     INCOMPATIBILITY.
  1593   - Renamed options:
  1594     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1595     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1596     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1597     (and "ms" and "min" are no longer supported)
  1598     INCOMPATIBILITY.
  1599 
  1600 * Nitpick:
  1601   - Renamed options:
  1602     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1603     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1604     INCOMPATIBILITY.
  1605   - Added support for partial quotient types.
  1606   - Added local versions of the "Nitpick.register_xxx" functions.
  1607   - Added "whack" option.
  1608   - Allow registration of quotient types as codatatypes.
  1609   - Improved "merge_type_vars" option to merge more types.
  1610   - Removed unsound "fast_descrs" option.
  1611   - Added custom symmetry breaking for datatypes, making it possible to reach
  1612     higher cardinalities.
  1613   - Prevent the expansion of too large definitions.
  1614 
  1615 * Proof methods "metis" and "meson" now have configuration options
  1616 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1617 to diagnose these tools. E.g.
  1618 
  1619     using [[metis_trace = true]]
  1620 
  1621 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1622 manually as command 'solve_direct'.
  1623 
  1624 * The default SMT solver Z3 must be enabled explicitly (due to
  1625 licensing issues) by setting the environment variable
  1626 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1627 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1628 changing the SMT solver is done via the configuration option
  1629 "smt_solver".
  1630 
  1631 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1632 i.e. "remote_cvc3" and "remote_z3".
  1633 
  1634 * Added basic SMT support for datatypes, records, and typedefs using
  1635 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1636 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1637 support for a similar behavior).  Minor INCOMPATIBILITY.
  1638 
  1639 * Changed SMT configuration options:
  1640   - Renamed:
  1641     z3_proofs ~> smt_oracle (with inverted meaning)
  1642     z3_trace_assms ~> smt_trace_used_facts
  1643     INCOMPATIBILITY.
  1644   - Added:
  1645     smt_verbose
  1646     smt_random_seed
  1647     smt_datatypes
  1648     smt_infer_triggers
  1649     smt_monomorph_limit
  1650     cvc3_options
  1651     remote_cvc3_options
  1652     remote_z3_options
  1653     yices_options
  1654 
  1655 * Boogie output files (.b2i files) need to be declared in the theory
  1656 header.
  1657 
  1658 * Simplification procedure "list_to_set_comprehension" rewrites list
  1659 comprehensions applied to List.set to set comprehensions.  Occasional
  1660 INCOMPATIBILITY, may be deactivated like this:
  1661 
  1662   declare [[simproc del: list_to_set_comprehension]]
  1663 
  1664 * Removed old version of primrec package.  INCOMPATIBILITY.
  1665 
  1666 * Removed simplifier congruence rule of "prod_case", as has for long
  1667 been the case with "split".  INCOMPATIBILITY.
  1668 
  1669 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1670 
  1671 * Removed [split_format ... and ... and ...] version of
  1672 [split_format].  Potential INCOMPATIBILITY.
  1673 
  1674 * Predicate "sorted" now defined inductively, with nice induction
  1675 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1676 
  1677 * Constant "contents" renamed to "the_elem", to free the generic name
  1678 contents for other uses.  INCOMPATIBILITY.
  1679 
  1680 * Renamed class eq and constant eq (for code generation) to class
  1681 equal and constant equal, plus renaming of related facts and various
  1682 tuning.  INCOMPATIBILITY.
  1683 
  1684 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1685 
  1686 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1687 INCOMPATIBILITY.
  1688 
  1689 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1690 avoid confusion with finite sets.  INCOMPATIBILITY.
  1691 
  1692 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1693 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1694 for congruent(2)).
  1695 
  1696 * Some previously unqualified names have been qualified:
  1697 
  1698   types
  1699     bool ~> HOL.bool
  1700     nat ~> Nat.nat
  1701 
  1702   constants
  1703     Trueprop ~> HOL.Trueprop
  1704     True ~> HOL.True
  1705     False ~> HOL.False
  1706     op & ~> HOL.conj
  1707     op | ~> HOL.disj
  1708     op --> ~> HOL.implies
  1709     op = ~> HOL.eq
  1710     Not ~> HOL.Not
  1711     The ~> HOL.The
  1712     All ~> HOL.All
  1713     Ex ~> HOL.Ex
  1714     Ex1 ~> HOL.Ex1
  1715     Let ~> HOL.Let
  1716     If ~> HOL.If
  1717     Ball ~> Set.Ball
  1718     Bex ~> Set.Bex
  1719     Suc ~> Nat.Suc
  1720     Pair ~> Product_Type.Pair
  1721     fst ~> Product_Type.fst
  1722     snd ~> Product_Type.snd
  1723     curry ~> Product_Type.curry
  1724     op : ~> Set.member
  1725     Collect ~> Set.Collect
  1726 
  1727 INCOMPATIBILITY.
  1728 
  1729 * More canonical naming convention for some fundamental definitions:
  1730 
  1731     bot_bool_eq ~> bot_bool_def
  1732     top_bool_eq ~> top_bool_def
  1733     inf_bool_eq ~> inf_bool_def
  1734     sup_bool_eq ~> sup_bool_def
  1735     bot_fun_eq  ~> bot_fun_def
  1736     top_fun_eq  ~> top_fun_def
  1737     inf_fun_eq  ~> inf_fun_def
  1738     sup_fun_eq  ~> sup_fun_def
  1739 
  1740 INCOMPATIBILITY.
  1741 
  1742 * More stylized fact names:
  1743 
  1744   expand_fun_eq ~> fun_eq_iff
  1745   expand_set_eq ~> set_eq_iff
  1746   set_ext       ~> set_eqI
  1747   nat_number    ~> eval_nat_numeral
  1748 
  1749 INCOMPATIBILITY.
  1750 
  1751 * Refactoring of code-generation specific operations in theory List:
  1752 
  1753   constants
  1754     null ~> List.null
  1755 
  1756   facts
  1757     mem_iff ~> member_def
  1758     null_empty ~> null_def
  1759 
  1760 INCOMPATIBILITY.  Note that these were not supposed to be used
  1761 regularly unless for striking reasons; their main purpose was code
  1762 generation.
  1763 
  1764 Various operations from the Haskell prelude are used for generating
  1765 Haskell code.
  1766 
  1767 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1768 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1769 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1770 
  1771 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1772 "*" and "+" respectively.  INCOMPATIBILITY.
  1773 
  1774 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1775 "Sum_Type.Plus" instead.
  1776 
  1777 * Constant "split" has been merged with constant "prod_case"; names of
  1778 ML functions, facts etc. involving split have been retained so far,
  1779 though.  INCOMPATIBILITY.
  1780 
  1781 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1782 instead.  INCOMPATIBILITY.
  1783 
  1784 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1785 INCOMPATIBILITY.
  1786 
  1787 * Former theory Library/Enum is now part of the HOL-Main image.
  1788 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1789 referred to by its qualified name.
  1790 
  1791   enum    ~>  Enum.enum
  1792   nlists  ~>  Enum.nlists
  1793   product ~>  Enum.product
  1794 
  1795 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1796 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1797 INCOMPATIBILITY.
  1798 
  1799 * Theory Library/SetsAndFunctions has been split into
  1800 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1801 for instance definitions for functions; various improvements.
  1802 INCOMPATIBILITY.
  1803 
  1804 * Theory Library/Multiset provides stable quicksort implementation of
  1805 sort_key.
  1806 
  1807 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1808 INCOMPATIBILITY.
  1809 
  1810 * Session Multivariate_Analysis: introduced a type class for euclidean
  1811 space.  Most theorems are now stated in terms of euclidean spaces
  1812 instead of finite cartesian products.
  1813 
  1814   types
  1815     real ^ 'n ~>  'a::real_vector
  1816               ~>  'a::euclidean_space
  1817               ~>  'a::ordered_euclidean_space
  1818         (depends on your needs)
  1819 
  1820   constants
  1821      _ $ _        ~> _ $$ _
  1822      \<chi> x. _  ~> \<chi>\<chi> x. _
  1823      CARD('n)     ~> DIM('a)
  1824 
  1825 Also note that the indices are now natural numbers and not from some
  1826 finite type. Finite cartesian products of euclidean spaces, products
  1827 of euclidean spaces the real and complex numbers are instantiated to
  1828 be euclidean_spaces.  INCOMPATIBILITY.
  1829 
  1830 * Session Probability: introduced pextreal as positive extended real
  1831 numbers.  Use pextreal as value for measures.  Introduce the
  1832 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1833 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1834 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1835 
  1836 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1837 INCOMPATIBILITY.
  1838 
  1839 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1840 prove verification conditions generated by the SPARK Ada program
  1841 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1842 
  1843 
  1844 *** HOL-Algebra ***
  1845 
  1846 * Theorems for additive ring operations (locale abelian_monoid and
  1847 descendants) are generated by interpretation from their multiplicative
  1848 counterparts.  Names (in particular theorem names) have the mandatory
  1849 qualifier 'add'.  Previous theorem names are redeclared for
  1850 compatibility.
  1851 
  1852 * Structure "int_ring" is now an abbreviation (previously a
  1853 definition).  This fits more natural with advanced interpretations.
  1854 
  1855 
  1856 *** HOLCF ***
  1857 
  1858 * The domain package now runs in definitional mode by default: The
  1859 former command 'new_domain' is now called 'domain'.  To use the domain
  1860 package in its original axiomatic mode, use 'domain (unsafe)'.
  1861 INCOMPATIBILITY.
  1862 
  1863 * The new class "domain" is now the default sort.  Class "predomain"
  1864 is an unpointed version of "domain". Theories can be updated by
  1865 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1866 
  1867   'a::type ~> 'a::countable
  1868   'a::cpo  ~> 'a::predomain
  1869   'a::pcpo ~> 'a::domain
  1870 
  1871 * The old type class "rep" has been superseded by class "domain".
  1872 Accordingly, users of the definitional package must remove any
  1873 "default_sort rep" declarations.  INCOMPATIBILITY.
  1874 
  1875 * The domain package (definitional mode) now supports unpointed
  1876 predomain argument types, as long as they are marked 'lazy'. (Strict
  1877 arguments must be in class "domain".) For example, the following
  1878 domain definition now works:
  1879 
  1880   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1881 
  1882 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1883 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1884 'a option, and 'a list.  Additionally, it configures fixrec and the
  1885 domain package to work with these types.  For example:
  1886 
  1887   fixrec isInl :: "('a + 'b) u -> tr"
  1888     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1889 
  1890   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1891 
  1892 * The "(permissive)" option of fixrec has been replaced with a
  1893 per-equation "(unchecked)" option. See
  1894 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1895 
  1896 * The "bifinite" class no longer fixes a constant "approx"; the class
  1897 now just asserts that such a function exists.  INCOMPATIBILITY.
  1898 
  1899 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1900 defines an embedding of type 'a defl into udom by default; instances
  1901 of "bifinite" and "domain" classes are available in
  1902 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1903 
  1904 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1905 
  1906 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1907 
  1908 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1909 
  1910 * The function "cprod_map" has been renamed to "prod_map".
  1911 INCOMPATIBILITY.
  1912 
  1913 * The monadic bind operator on each powerdomain has new binder syntax
  1914 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1915 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1916 
  1917 * The infix syntax for binary union on each powerdomain has changed
  1918 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1919 syntax.  INCOMPATIBILITY.
  1920 
  1921 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1922 still supported as an input translation.
  1923 
  1924 * Renamed some theorems (the original names are also still available).
  1925 
  1926   expand_fun_below   ~> fun_below_iff
  1927   below_fun_ext      ~> fun_belowI
  1928   expand_cfun_eq     ~> cfun_eq_iff
  1929   ext_cfun           ~> cfun_eqI
  1930   expand_cfun_below  ~> cfun_below_iff
  1931   below_cfun_ext     ~> cfun_belowI
  1932   cont2cont_Rep_CFun ~> cont2cont_APP
  1933 
  1934 * The Abs and Rep functions for various types have changed names.
  1935 Related theorem names have also changed to match. INCOMPATIBILITY.
  1936 
  1937   Rep_CFun  ~> Rep_cfun
  1938   Abs_CFun  ~> Abs_cfun
  1939   Rep_Sprod ~> Rep_sprod
  1940   Abs_Sprod ~> Abs_sprod
  1941   Rep_Ssum  ~> Rep_ssum
  1942   Abs_Ssum  ~> Abs_ssum
  1943 
  1944 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1945 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1946 
  1947 * Various changes to bisimulation/coinduction with domain package:
  1948 
  1949   - Definitions of "bisim" constants no longer mention definedness.
  1950   - With mutual recursion, "bisim" predicate is now curried.
  1951   - With mutual recursion, each type gets a separate coind theorem.
  1952   - Variable names in bisim_def and coinduct rules have changed.
  1953 
  1954 INCOMPATIBILITY.
  1955 
  1956 * Case combinators generated by the domain package for type "foo" are
  1957 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1958 
  1959 * Several theorems have been renamed to more accurately reflect the
  1960 names of constants and types involved.  INCOMPATIBILITY.
  1961 
  1962   thelub_const    ~> lub_const
  1963   lub_const       ~> is_lub_const
  1964   thelubI         ~> lub_eqI
  1965   is_lub_lub      ~> is_lubD2
  1966   lubI            ~> is_lub_lub
  1967   unique_lub      ~> is_lub_unique
  1968   is_ub_lub       ~> is_lub_rangeD1
  1969   lub_bin_chain   ~> is_lub_bin_chain
  1970   lub_fun         ~> is_lub_fun
  1971   thelub_fun      ~> lub_fun
  1972   thelub_cfun     ~> lub_cfun
  1973   thelub_Pair     ~> lub_Pair
  1974   lub_cprod       ~> is_lub_prod
  1975   thelub_cprod    ~> lub_prod
  1976   minimal_cprod   ~> minimal_prod
  1977   inst_cprod_pcpo ~> inst_prod_pcpo
  1978   UU_I            ~> bottomI
  1979   compact_UU      ~> compact_bottom
  1980   deflation_UU    ~> deflation_bottom
  1981   finite_deflation_UU ~> finite_deflation_bottom
  1982 
  1983 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1984 
  1985   sq_ord_less_eq_trans ~> below_eq_trans
  1986   sq_ord_eq_less_trans ~> eq_below_trans
  1987   refl_less            ~> below_refl
  1988   trans_less           ~> below_trans
  1989   antisym_less         ~> below_antisym
  1990   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1991   box_less             ~> box_below
  1992   rev_trans_less       ~> rev_below_trans
  1993   not_less2not_eq      ~> not_below2not_eq
  1994   less_UU_iff          ~> below_UU_iff
  1995   flat_less_iff        ~> flat_below_iff
  1996   adm_less             ~> adm_below
  1997   adm_not_less         ~> adm_not_below
  1998   adm_compact_not_less ~> adm_compact_not_below
  1999   less_fun_def         ~> below_fun_def
  2000   expand_fun_less      ~> fun_below_iff
  2001   less_fun_ext         ~> fun_belowI
  2002   less_discr_def       ~> below_discr_def
  2003   discr_less_eq        ~> discr_below_eq
  2004   less_unit_def        ~> below_unit_def
  2005   less_cprod_def       ~> below_prod_def
  2006   prod_lessI           ~> prod_belowI
  2007   Pair_less_iff        ~> Pair_below_iff
  2008   fst_less_iff         ~> fst_below_iff
  2009   snd_less_iff         ~> snd_below_iff
  2010   expand_cfun_less     ~> cfun_below_iff
  2011   less_cfun_ext        ~> cfun_belowI
  2012   injection_less       ~> injection_below
  2013   less_up_def          ~> below_up_def
  2014   not_Iup_less         ~> not_Iup_below
  2015   Iup_less             ~> Iup_below
  2016   up_less              ~> up_below
  2017   Def_inject_less_eq   ~> Def_below_Def
  2018   Def_less_is_eq       ~> Def_below_iff
  2019   spair_less_iff       ~> spair_below_iff
  2020   less_sprod           ~> below_sprod
  2021   spair_less           ~> spair_below
  2022   sfst_less_iff        ~> sfst_below_iff
  2023   ssnd_less_iff        ~> ssnd_below_iff
  2024   fix_least_less       ~> fix_least_below
  2025   dist_less_one        ~> dist_below_one
  2026   less_ONE             ~> below_ONE
  2027   ONE_less_iff         ~> ONE_below_iff
  2028   less_sinlD           ~> below_sinlD
  2029   less_sinrD           ~> below_sinrD
  2030 
  2031 
  2032 *** FOL and ZF ***
  2033 
  2034 * All constant names are now qualified internally and use proper
  2035 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  2036 
  2037 
  2038 *** ML ***
  2039 
  2040 * Antiquotation @{assert} inlines a function bool -> unit that raises
  2041 Fail if the argument is false.  Due to inlining the source position of
  2042 failed assertions is included in the error output.
  2043 
  2044 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  2045 text is in practice always evaluated with a stable theory checkpoint.
  2046 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  2047 
  2048 * Antiquotation @{theory A} refers to theory A from the ancestry of
  2049 the current context, not any accidental theory loader state as before.
  2050 Potential INCOMPATIBILITY, subtle change in semantics.
  2051 
  2052 * Syntax.pretty_priority (default 0) configures the required priority
  2053 of pretty-printed output and thus affects insertion of parentheses.
  2054 
  2055 * Syntax.default_root (default "any") configures the inner syntax
  2056 category (nonterminal symbol) for parsing of terms.
  2057 
  2058 * Former exception Library.UnequalLengths now coincides with
  2059 ListPair.UnequalLengths.
  2060 
  2061 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  2062 main functionality is provided by structure Simplifier.
  2063 
  2064 * Renamed raw "explode" function to "raw_explode" to emphasize its
  2065 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  2066 almost all situations.
  2067 
  2068 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  2069 See implementation manual for further details on exceptions in
  2070 Isabelle/ML.
  2071 
  2072 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  2073 meaning.
  2074 
  2075 * Renamed structure PureThy to Pure_Thy and moved most of its
  2076 operations to structure Global_Theory, to emphasize that this is
  2077 rarely-used global-only stuff.
  2078 
  2079 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  2080 instead (or tracing for high-volume output).
  2081 
  2082 * Configuration option show_question_marks only affects regular pretty
  2083 printing of types and terms, not raw Term.string_of_vname.
  2084 
  2085 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  2086 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  2087 @{thms} for most purposes.
  2088 
  2089 * ML structure Unsynchronized is never opened, not even in Isar
  2090 interaction mode as before.  Old Unsynchronized.set etc. have been
  2091 discontinued -- use plain := instead.  This should be *rare* anyway,
  2092 since modern tools always work via official context data, notably
  2093 configuration options.
  2094 
  2095 * Parallel and asynchronous execution requires special care concerning
  2096 interrupts.  Structure Exn provides some convenience functions that
  2097 avoid working directly with raw Interrupt.  User code must not absorb
  2098 interrupts -- intermediate handling (for cleanup etc.) needs to be
  2099 followed by re-raising of the original exception.  Another common
  2100 source of mistakes are "handle _" patterns, which make the meaning of
  2101 the program subject to physical effects of the environment.
  2102 
  2103 
  2104 
  2105 New in Isabelle2009-2 (June 2010)
  2106 ---------------------------------
  2107 
  2108 *** General ***
  2109 
  2110 * Authentic syntax for *all* logical entities (type classes, type
  2111 constructors, term constants): provides simple and robust
  2112 correspondence between formal entities and concrete syntax.  Within
  2113 the parse tree / AST representations, "constants" are decorated by
  2114 their category (class, type, const) and spelled out explicitly with
  2115 their full internal name.
  2116 
  2117 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  2118 and translations (translation rules and translation functions in ML).
  2119 Some hints on upgrading:
  2120 
  2121   - Many existing uses of 'syntax' and 'translations' can be replaced
  2122     by more modern 'type_notation', 'notation' and 'abbreviation',
  2123     which are independent of this issue.
  2124 
  2125   - 'translations' require markup within the AST; the term syntax
  2126     provides the following special forms:
  2127 
  2128       CONST c   -- produces syntax version of constant c from context
  2129       XCONST c  -- literally c, checked as constant from context
  2130       c         -- literally c, if declared by 'syntax'
  2131 
  2132     Plain identifiers are treated as AST variables -- occasionally the
  2133     system indicates accidental variables via the error "rhs contains
  2134     extra variables".
  2135 
  2136     Type classes and type constructors are marked according to their
  2137     concrete syntax.  Some old translations rules need to be written
  2138     for the "type" category, using type constructor application
  2139     instead of pseudo-term application of the default category
  2140     "logic".
  2141 
  2142   - 'parse_translation' etc. in ML may use the following
  2143     antiquotations:
  2144 
  2145       @{class_syntax c}   -- type class c within parse tree / AST
  2146       @{term_syntax c}    -- type constructor c within parse tree / AST
  2147       @{const_syntax c}   -- ML version of "CONST c" above
  2148       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  2149 
  2150   - Literal types within 'typed_print_translations', i.e. those *not*
  2151     represented as pseudo-terms are represented verbatim.  Use @{class
  2152     c} or @{type_name c} here instead of the above syntax
  2153     antiquotations.
  2154 
  2155 Note that old non-authentic syntax was based on unqualified base
  2156 names, so all of the above "constant" names would coincide.  Recall
  2157 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  2158 diagnose syntax problems.
  2159 
  2160 * Type constructors admit general mixfix syntax, not just infix.
  2161 
  2162 * Concrete syntax may be attached to local entities without a proof
  2163 body, too.  This works via regular mixfix annotations for 'fix',
  2164 'def', 'obtain' etc. or via the explicit 'write' command, which is
  2165 similar to the 'notation' command in theory specifications.
  2166 
  2167 * Discontinued unnamed infix syntax (legacy feature for many years) --
  2168 need to specify constant name and syntax separately.  Internal ML
  2169 datatype constructors have been renamed from InfixName to Infix etc.
  2170 Minor INCOMPATIBILITY.
  2171 
  2172 * Schematic theorem statements need to be explicitly markup as such,
  2173 via commands 'schematic_lemma', 'schematic_theorem',
  2174 'schematic_corollary'.  Thus the relevance of the proof is made
  2175 syntactically clear, which impacts performance in a parallel or
  2176 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  2177 
  2178 * Use of cumulative prems via "!" in some proof methods has been
  2179 discontinued (old legacy feature).
  2180 
  2181 * References 'trace_simp' and 'debug_simp' have been replaced by
  2182 configuration options stored in the context. Enabling tracing (the
  2183 case of debugging is similar) in proofs works via
  2184 
  2185   using [[trace_simp = true]]
  2186 
  2187 Tracing is then active for all invocations of the simplifier in
  2188 subsequent goal refinement steps. Tracing may also still be enabled or
  2189 disabled via the ProofGeneral settings menu.
  2190 
  2191 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  2192 'hide_fact' replace the former 'hide' KIND command.  Minor
  2193 INCOMPATIBILITY.
  2194 
  2195 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  2196 more efficient than combinations with -q1 or -q2.
  2197 
  2198 
  2199 *** Pure ***
  2200 
  2201 * Proofterms record type-class reasoning explicitly, using the
  2202 "unconstrain" operation internally.  This eliminates all sort
  2203 constraints from a theorem and proof, introducing explicit
  2204 OFCLASS-premises.  On the proof term level, this operation is
  2205 automatically applied at theorem boundaries, such that closed proofs
  2206 are always free of sort constraints.  INCOMPATIBILITY for tools that
  2207 inspect proof terms.
  2208 
  2209 * Local theory specifications may depend on extra type variables that
  2210 are not present in the result type -- arguments TYPE('a) :: 'a itself
  2211 are added internally.  For example:
  2212 
  2213   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  2214 
  2215 * Predicates of locales introduced by classes carry a mandatory
  2216 "class" prefix.  INCOMPATIBILITY.
  2217 
  2218 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  2219 
  2220 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  2221 'class' instead.
  2222 
  2223 * Command 'code_reflect' allows to incorporate generated ML code into
  2224 runtime environment; replaces immature code_datatype antiquotation.
  2225 INCOMPATIBILITY.
  2226 
  2227 * Code generator: simple concept for abstract datatypes obeying
  2228 invariants.
  2229 
  2230 * Code generator: details of internal data cache have no impact on the
  2231 user space functionality any longer.
  2232 
  2233 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  2234 subgoals.  This is more appropriate for interpretations with 'where'.
  2235 INCOMPATIBILITY.
  2236 
  2237 * Command 'example_proof' opens an empty proof body.  This allows to
  2238 experiment with Isar, without producing any persistent result.
  2239 
  2240 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  2241 within a local theory context, with explicit checking of the
  2242 constructors involved (in contrast to the raw 'syntax' versions).
  2243 
  2244 * Commands 'types' and 'typedecl' now work within a local theory
  2245 context -- without introducing dependencies on parameters or
  2246 assumptions, which is not possible in Isabelle/Pure.
  2247 
  2248 * Command 'defaultsort' has been renamed to 'default_sort', it works
  2249 within a local theory context.  Minor INCOMPATIBILITY.
  2250 
  2251 
  2252 *** HOL ***
  2253 
  2254 * Command 'typedef' now works within a local theory context -- without
  2255 introducing dependencies on parameters or assumptions, which is not
  2256 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  2257 contain multiple interpretations of local typedefs (with different
  2258 non-emptiness proofs), even in a global theory context.
  2259 
  2260 * New package for quotient types.  Commands 'quotient_type' and
  2261 'quotient_definition' may be used for defining types and constants by
  2262 quotient constructions.  An example is the type of integers created by
  2263 quotienting pairs of natural numbers:
  2264 
  2265   fun
  2266     intrel :: "(nat * nat) => (nat * nat) => bool"
  2267   where
  2268     "intrel (x, y) (u, v) = (x + v = u + y)"
  2269 
  2270   quotient_type int = "nat * nat" / intrel
  2271     by (auto simp add: equivp_def expand_fun_eq)
  2272 
  2273   quotient_definition
  2274     "0::int" is "(0::nat, 0::nat)"
  2275 
  2276 The method "lifting" can be used to lift of theorems from the
  2277 underlying "raw" type to the quotient type.  The example
  2278 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  2279 construction and provides a reasoning infrastructure for finite sets.
  2280 
  2281 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  2282 clash with new theory Quotient in Main HOL.
  2283 
  2284 * Moved the SMT binding into the main HOL session, eliminating
  2285 separate HOL-SMT session.
  2286 
  2287 * List membership infix mem operation is only an input abbreviation.
  2288 INCOMPATIBILITY.
  2289 
  2290 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  2291 for future developements; former Library/Word.thy is still present in
  2292 the AFP entry RSAPPS.
  2293 
  2294 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  2295 longer shadowed.  INCOMPATIBILITY.
  2296 
  2297 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  2298 INCOMPATIBILITY.
  2299 
  2300 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  2301 INCOMPATIBILITY.
  2302 
  2303 * Dropped normalizing_semiring etc; use the facts in semiring classes
  2304 instead.  INCOMPATIBILITY.
  2305 
  2306 * Dropped several real-specific versions of lemmas about floor and
  2307 ceiling; use the generic lemmas from theory "Archimedean_Field"
  2308 instead.  INCOMPATIBILITY.
  2309 
  2310   floor_number_of_eq         ~> floor_number_of
  2311   le_floor_eq_number_of      ~> number_of_le_floor
  2312   le_floor_eq_zero           ~> zero_le_floor
  2313   le_floor_eq_one            ~> one_le_floor
  2314   floor_less_eq_number_of    ~> floor_less_number_of
  2315   floor_less_eq_zero         ~> floor_less_zero
  2316   floor_less_eq_one          ~> floor_less_one
  2317   less_floor_eq_number_of    ~> number_of_less_floor
  2318   less_floor_eq_zero         ~> zero_less_floor
  2319   less_floor_eq_one          ~> one_less_floor
  2320   floor_le_eq_number_of      ~> floor_le_number_of
  2321   floor_le_eq_zero           ~> floor_le_zero
  2322   floor_le_eq_one            ~> floor_le_one
  2323   floor_subtract_number_of   ~> floor_diff_number_of
  2324   floor_subtract_one         ~> floor_diff_one
  2325   ceiling_number_of_eq       ~> ceiling_number_of
  2326   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  2327   ceiling_le_zero_eq         ~> ceiling_le_zero
  2328   ceiling_le_eq_one          ~> ceiling_le_one
  2329   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  2330   less_ceiling_eq_zero       ~> zero_less_ceiling
  2331   less_ceiling_eq_one        ~> one_less_ceiling
  2332   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  2333   ceiling_less_eq_zero       ~> ceiling_less_zero
  2334   ceiling_less_eq_one        ~> ceiling_less_one
  2335   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  2336   le_ceiling_eq_zero         ~> zero_le_ceiling
  2337   le_ceiling_eq_one          ~> one_le_ceiling
  2338   ceiling_subtract_number_of ~> ceiling_diff_number_of
  2339   ceiling_subtract_one       ~> ceiling_diff_one
  2340 
  2341 * Theory "Finite_Set": various folding_XXX locales facilitate the
  2342 application of the various fold combinators on finite sets.
  2343 
  2344 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  2345 provides abstract red-black tree type which is backed by "RBT_Impl" as
  2346 implementation.  INCOMPATIBILTY.
  2347 
  2348 * Theory Library/Coinductive_List has been removed -- superseded by
  2349 AFP/thys/Coinductive.
  2350 
  2351 * Theory PReal, including the type "preal" and related operations, has
  2352 been removed.  INCOMPATIBILITY.
  2353 
  2354 * Real: new development using Cauchy Sequences.
  2355 
  2356 * Split off theory "Big_Operators" containing setsum, setprod,
  2357 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  2358 
  2359 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  2360 "Int" etc.  INCOMPATIBILITY.
  2361 
  2362 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  2363 
  2364 * New set of rules "ac_simps" provides combined assoc / commute
  2365 rewrites for all interpretations of the appropriate generic locales.
  2366 
  2367 * Renamed theory "OrderedGroup" to "Groups" and split theory
  2368 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  2369 appropriate and more consistent names suitable for name prefixes
  2370 within the HOL theories.  INCOMPATIBILITY.
  2371 
  2372 * Some generic constants have been put to appropriate theories:
  2373   - less_eq, less: Orderings
  2374   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  2375   - inverse, divide: Rings
  2376 INCOMPATIBILITY.
  2377 
  2378 * More consistent naming of type classes involving orderings (and
  2379 lattices):
  2380 
  2381     lower_semilattice                   ~> semilattice_inf
  2382     upper_semilattice                   ~> semilattice_sup
  2383 
  2384     dense_linear_order                  ~> dense_linorder
  2385 
  2386     pordered_ab_group_add               ~> ordered_ab_group_add
  2387     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  2388     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  2389     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  2390     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  2391     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  2392     pordered_cancel_semiring            ~> ordered_cancel_semiring
  2393     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  2394     pordered_comm_ring                  ~> ordered_comm_ring
  2395     pordered_comm_semiring              ~> ordered_comm_semiring
  2396     pordered_ring                       ~> ordered_ring
  2397     pordered_ring_abs                   ~> ordered_ring_abs
  2398     pordered_semiring                   ~> ordered_semiring
  2399 
  2400     ordered_ab_group_add                ~> linordered_ab_group_add
  2401     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  2402     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  2403     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  2404     ordered_field                       ~> linordered_field
  2405     ordered_field_no_lb                 ~> linordered_field_no_lb
  2406     ordered_field_no_ub                 ~> linordered_field_no_ub
  2407     ordered_field_dense_linear_order    ~> dense_linordered_field
  2408     ordered_idom                        ~> linordered_idom
  2409     ordered_ring                        ~> linordered_ring
  2410     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  2411     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  2412     ordered_ring_strict                 ~> linordered_ring_strict
  2413     ordered_semidom                     ~> linordered_semidom
  2414     ordered_semiring                    ~> linordered_semiring
  2415     ordered_semiring_1                  ~> linordered_semiring_1
  2416     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  2417     ordered_semiring_strict             ~> linordered_semiring_strict
  2418 
  2419   The following slightly odd type classes have been moved to a
  2420   separate theory Library/Lattice_Algebras:
  2421 
  2422     lordered_ab_group_add               ~> lattice_ab_group_add
  2423     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  2424     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  2425     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  2426     lordered_ring                       ~> lattice_ring
  2427 
  2428 INCOMPATIBILITY.
  2429 
  2430 * Refined field classes:
  2431   - classes division_ring_inverse_zero, field_inverse_zero,
  2432     linordered_field_inverse_zero include rule inverse 0 = 0 --
  2433     subsumes former division_by_zero class;
  2434   - numerous lemmas have been ported from field to division_ring.
  2435 INCOMPATIBILITY.
  2436 
  2437 * Refined algebra theorem collections:
  2438   - dropped theorem group group_simps, use algebra_simps instead;
  2439   - dropped theorem group ring_simps, use field_simps instead;
  2440   - proper theorem collection field_simps subsumes former theorem
  2441     groups field_eq_simps and field_simps;
  2442   - dropped lemma eq_minus_self_iff which is a duplicate for
  2443     equal_neg_zero.
  2444 INCOMPATIBILITY.
  2445 
  2446 * Theory Finite_Set and List: some lemmas have been generalized from
  2447 sets to lattices:
  2448 
  2449   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  2450   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  2451   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  2452   union_Union_fold_union        ~> sup_Sup_fold_sup
  2453   Inter_fold_inter              ~> Inf_fold_inf
  2454   Union_fold_union              ~> Sup_fold_sup
  2455   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  2456   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  2457   INTER_fold_inter              ~> INFI_fold_inf
  2458   UNION_fold_union              ~> SUPR_fold_sup
  2459 
  2460 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  2461 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  2462 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  2463 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  2464 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  2465 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  2466 
  2467 * Reorganized theory Multiset: swapped notation of pointwise and
  2468 multiset order:
  2469 
  2470   - pointwise ordering is instance of class order with standard syntax
  2471     <= and <;
  2472   - multiset ordering has syntax <=# and <#; partial order properties
  2473     are provided by means of interpretation with prefix
  2474     multiset_order;
  2475   - less duplication, less historical organization of sections,
  2476     conversion from associations lists to multisets, rudimentary code
  2477     generation;
  2478   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  2479     if needed.
  2480 
  2481 Renamed:
  2482 
  2483   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  2484   multi_count_ext  ~>  multiset_ext
  2485   diff_union_inverse2  ~>  diff_union_cancelR
  2486 
  2487 INCOMPATIBILITY.
  2488 
  2489 * Theory Permutation: replaced local "remove" by List.remove1.
  2490 
  2491 * Code generation: ML and OCaml code is decorated with signatures.
  2492 
  2493 * Theory List: added transpose.
  2494 
  2495 * Library/Nat_Bijection.thy is a collection of bijective functions
  2496 between nat and other types, which supersedes the older libraries
  2497 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2498 
  2499   Constants:
  2500   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2501   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2502   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2503   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2504   Countable.pair_encode           ~> prod_encode
  2505   NatIso.prod2nat                 ~> prod_encode
  2506   NatIso.nat2prod                 ~> prod_decode
  2507   NatIso.sum2nat                  ~> sum_encode
  2508   NatIso.nat2sum                  ~> sum_decode
  2509   NatIso.list2nat                 ~> list_encode
  2510   NatIso.nat2list                 ~> list_decode
  2511   NatIso.set2nat                  ~> set_encode
  2512   NatIso.nat2set                  ~> set_decode
  2513 
  2514   Lemmas:
  2515   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2516   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2517   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2518   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2519   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2520   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2521   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2522   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2523   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2524   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2525   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2526   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2527   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2528 
  2529 * Sledgehammer:
  2530   - Renamed ATP commands:
  2531     atp_info     ~> sledgehammer running_atps
  2532     atp_kill     ~> sledgehammer kill_atps
  2533     atp_messages ~> sledgehammer messages
  2534     atp_minimize ~> sledgehammer minimize
  2535     print_atps   ~> sledgehammer available_atps
  2536     INCOMPATIBILITY.
  2537   - Added user's manual ("isabelle doc sledgehammer").
  2538   - Added option syntax and "sledgehammer_params" to customize
  2539     Sledgehammer's behavior.  See the manual for details.
  2540   - Modified the Isar proof reconstruction code so that it produces
  2541     direct proofs rather than proofs by contradiction.  (This feature
  2542     is still experimental.)
  2543   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2544     full-typed mode.
  2545   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2546 
  2547 * Nitpick:
  2548   - Added and implemented "binary_ints" and "bits" options.
  2549   - Added "std" option and implemented support for nonstandard models.
  2550   - Added and implemented "finitize" option to improve the precision
  2551     of infinite datatypes based on a monotonicity analysis.
  2552   - Added support for quotient types.
  2553   - Added support for "specification" and "ax_specification"
  2554     constructs.
  2555   - Added support for local definitions (for "function" and
  2556     "termination" proofs).
  2557   - Added support for term postprocessors.
  2558   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2559   - Improved efficiency of "destroy_constrs" optimization.
  2560   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2561     record getters.
  2562   - Fixed soundness bug related to higher-order constructors.
  2563   - Fixed soundness bug when "full_descrs" is enabled.
  2564   - Improved precision of set constructs.
  2565   - Added "atoms" option.
  2566   - Added cache to speed up repeated Kodkod invocations on the same
  2567     problems.
  2568   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2569     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2570     "SAT4J_Light".  INCOMPATIBILITY.
  2571   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2572     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2573   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2574 
  2575 * Method "induct" now takes instantiations of the form t, where t is not
  2576   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2577   If this is not intended, t has to be enclosed in parentheses.
  2578   By default, the equalities generated by definitional instantiations
  2579   are pre-simplified, which may cause parameters of inductive cases
  2580   to disappear, or may even delete some of the inductive cases.
  2581   Use "induct (no_simp)" instead of "induct" to restore the old
  2582   behaviour. The (no_simp) option is also understood by the "cases"
  2583   and "nominal_induct" methods, which now perform pre-simplification, too.
  2584   INCOMPATIBILITY.
  2585 
  2586 
  2587 *** HOLCF ***
  2588 
  2589 * Variable names in lemmas generated by the domain package have
  2590 changed; the naming scheme is now consistent with the HOL datatype
  2591 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2592 
  2593 * The domain package no longer defines the function "foo_copy" for
  2594 recursive domain "foo".  The reach lemma is now stated directly in
  2595 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2596 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2597 
  2598 * Most definedness lemmas generated by the domain package (previously
  2599 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2600 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2601 Proofs that used definedness lemmas as intro rules may break,
  2602 potential INCOMPATIBILITY.
  2603 
  2604 * Induction and casedist rules generated by the domain package now
  2605 declare proper case_names (one called "bottom", and one named for each
  2606 constructor).  INCOMPATIBILITY.
  2607 
  2608 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2609 rules are generated for each domain, INCOMPATIBILITY.
  2610 
  2611   foo_bar.reach       ~> foo.reach  bar.reach
  2612   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2613 
  2614 * Some lemmas generated by the domain package have been renamed for
  2615 consistency with the datatype package, INCOMPATIBILITY.
  2616 
  2617   foo.ind        ~> foo.induct
  2618   foo.finite_ind ~> foo.finite_induct
  2619   foo.coind      ~> foo.coinduct
  2620   foo.casedist   ~> foo.exhaust
  2621   foo.exhaust    ~> foo.nchotomy
  2622 
  2623 * For consistency with other definition packages, the fixrec package
  2624 now generates qualified theorem names, INCOMPATIBILITY.
  2625 
  2626   foo_simps  ~> foo.simps
  2627   foo_unfold ~> foo.unfold
  2628   foo_induct ~> foo.induct
  2629 
  2630 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2631 method and internal fixrec proofs now use the default simpset instead.
  2632 INCOMPATIBILITY.
  2633 
  2634 * The "contlub" predicate has been removed.  Proof scripts should use
  2635 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2636 
  2637 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2638 
  2639 * The constants cpair, cfst, and csnd have been removed in favor of
  2640 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2641 
  2642 
  2643 *** ML ***
  2644 
  2645 * Antiquotations for basic formal entities:
  2646 
  2647     @{class NAME}         -- type class
  2648     @{class_syntax NAME}  -- syntax representation of the above
  2649 
  2650     @{type_name NAME}     -- logical type
  2651     @{type_abbrev NAME}   -- type abbreviation
  2652     @{nonterminal NAME}   -- type of concrete syntactic category
  2653     @{type_syntax NAME}   -- syntax representation of any of the above
  2654 
  2655     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2656     @{const_abbrev NAME}  -- abbreviated constant
  2657     @{const_syntax NAME}  -- syntax representation of any of the above
  2658 
  2659 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2660 syntax constant (cf. 'syntax' command).
  2661 
  2662 * Antiquotation @{make_string} inlines a function to print arbitrary
  2663 values similar to the ML toplevel.  The result is compiler dependent
  2664 and may fall back on "?" in certain situations.
  2665 
  2666 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2667 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2668 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2669 not work with the asynchronous Isar document model.
  2670 
  2671 * Configuration options now admit dynamic default values, depending on
  2672 the context or even global references.
  2673 
  2674 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2675 uses an efficient external library if available (for Poly/ML).
  2676 
  2677 * Renamed some important ML structures, while keeping the old names
  2678 for some time as aliases within the structure Legacy:
  2679 
  2680   OuterKeyword  ~>  Keyword
  2681   OuterLex      ~>  Token
  2682   OuterParse    ~>  Parse
  2683   OuterSyntax   ~>  Outer_Syntax
  2684   PrintMode     ~>  Print_Mode
  2685   SpecParse     ~>  Parse_Spec
  2686   ThyInfo       ~>  Thy_Info
  2687   ThyLoad       ~>  Thy_Load
  2688   ThyOutput     ~>  Thy_Output
  2689   TypeInfer     ~>  Type_Infer
  2690 
  2691 Note that "open Legacy" simplifies porting of sources, but forgetting
  2692 to remove it again will complicate porting again in the future.
  2693 
  2694 * Most operations that refer to a global context are named
  2695 accordingly, e.g. Simplifier.global_context or
  2696 ProofContext.init_global.  There are some situations where a global
  2697 context actually works, but under normal circumstances one needs to
  2698 pass the proper local context through the code!
  2699 
  2700 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2701 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2702 Pretty.pp argument to merge, which is absent in the standard
  2703 Theory_Data version.
  2704 
  2705 * Sorts.certify_sort and derived "cert" operations for types and terms
  2706 no longer minimize sorts.  Thus certification at the boundary of the
  2707 inference kernel becomes invariant under addition of class relations,
  2708 which is an important monotonicity principle.  Sorts are now minimized
  2709 in the syntax layer only, at the boundary between the end-user and the
  2710 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2711 explicitly in rare situations.
  2712 
  2713 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2714 emphasize that this is in no way a standard operation.
  2715 INCOMPATIBILITY.
  2716 
  2717 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2718 usual for resolution.  Rare INCOMPATIBILITY.
  2719 
  2720 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2721 to emphasize that these only work in a global situation (which is
  2722 quite rare).
  2723 
  2724 * Curried take and drop in library.ML; negative length is interpreted
  2725 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2726 
  2727 * Proof terms: type substitutions on proof constants now use canonical
  2728 order of type variables.  INCOMPATIBILITY for tools working with proof
  2729 terms.
  2730 
  2731 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2732 may no longer carry premises.  User-level specifications are
  2733 transformed accordingly by Thm.add_axiom/add_def.
  2734 
  2735 
  2736 *** System ***
  2737 
  2738 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2739 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2740 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2741 
  2742 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2743 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2744 respectively.
  2745 
  2746 * Old lib/scripts/polyml-platform is superseded by the
  2747 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2748 variant, even on a 64 bit machine.  The following example setting
  2749 prefers 64 bit if available:
  2750 
  2751   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2752 
  2753 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2754 Isabelle/Scala layer for advanced prover interaction and integration.
  2755 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2756 component.
  2757 
  2758 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2759 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2760 similar to the default assignment of the document preparation system
  2761 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2762 provides some operations for direct access to the font without asking
  2763 the user for manual installation.
  2764 
  2765 
  2766 
  2767 New in Isabelle2009-1 (December 2009)
  2768 -------------------------------------
  2769 
  2770 *** General ***
  2771 
  2772 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2773 one backslash should be used, even in ML sources.
  2774 
  2775 
  2776 *** Pure ***
  2777 
  2778 * Locale interpretation propagates mixins along the locale hierarchy.
  2779 The currently only available mixins are the equations used to map
  2780 local definitions to terms of the target domain of an interpretation.
  2781 
  2782 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2783 loc" to print all interpretations of locale "loc" in the theory.
  2784 Interpretations in proofs are not shown.
  2785 
  2786 * Thoroughly revised locales tutorial.  New section on conditional
  2787 interpretation.
  2788 
  2789 * On instantiation of classes, remaining undefined class parameters
  2790 are formally declared.  INCOMPATIBILITY.
  2791 
  2792 
  2793 *** Document preparation ***
  2794 
  2795 * New generalized style concept for printing terms: @{foo (style) ...}
  2796 instead of @{foo_style style ...}  (old form is still retained for
  2797 backward compatibility).  Styles can be also applied for
  2798 antiquotations prop, term_type and typeof.
  2799 
  2800 
  2801 *** HOL ***
  2802 
  2803 * New proof method "smt" for a combination of first-order logic with
  2804 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2805 fixed-size bitvectors; there is also basic support for higher-order
  2806 features (esp. lambda abstractions).  It is an incomplete decision
  2807 procedure based on external SMT solvers using the oracle mechanism;
  2808 for the SMT solver Z3, this method is proof-producing.  Certificates
  2809 are provided to avoid calling the external solvers solely for
  2810 re-checking proofs.  Due to a remote SMT service there is no need for
  2811 installing SMT solvers locally.  See src/HOL/SMT.
  2812 
  2813 * New commands to load and prove verification conditions generated by
  2814 the Boogie program verifier or derived systems (e.g. the Verifying C
  2815 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2816 
  2817 * New counterexample generator tool 'nitpick' based on the Kodkod
  2818 relational model finder.  See src/HOL/Tools/Nitpick and
  2819 src/HOL/Nitpick_Examples.
  2820 
  2821 * New commands 'code_pred' and 'values' to invoke the predicate
  2822 compiler and to enumerate values of inductive predicates.
  2823 
  2824 * A tabled implementation of the reflexive transitive closure.
  2825 
  2826 * New implementation of quickcheck uses generic code generator;
  2827 default generators are provided for all suitable HOL types, records
  2828 and datatypes.  Old quickcheck can be re-activated importing theory
  2829 Library/SML_Quickcheck.
  2830 
  2831 * New testing tool Mirabelle for automated proof tools.  Applies
  2832 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2833 every proof step in a theory.  To be used in batch mode via the
  2834 "mirabelle" utility.
  2835 
  2836 * New proof method "sos" (sum of squares) for nonlinear real
  2837 arithmetic (originally due to John Harison). It requires theory
  2838 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2839 works well in practice on quantifier-free real arithmetic with +, -,
  2840 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2841 inequalities between polynomials.  It makes use of external
  2842 semidefinite programming solvers.  Method "sos" generates a
  2843 certificate that can be pasted into the proof thus avoiding the need
  2844 to call an external tool every time the proof is checked.  See
  2845 src/HOL/Library/Sum_Of_Squares.
  2846 
  2847 * New method "linarith" invokes existing linear arithmetic decision
  2848 procedure only.
  2849 
  2850 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2851 
  2852 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2853 Causes full type information to be output to the ATPs.  This slows
  2854 ATPs down considerably but eliminates a source of unsound "proofs"
  2855 that fail later.
  2856 
  2857 * New method "metisFT": A version of metis that uses full type
  2858 information in order to avoid failures of proof reconstruction.
  2859 
  2860 * New evaluator "approximate" approximates an real valued term using
  2861 the same method as the approximation method.
  2862 
  2863 * Method "approximate" now supports arithmetic expressions as
  2864 boundaries of intervals and implements interval splitting and Taylor
  2865 series expansion.
  2866 
  2867 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2868 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2869 
  2870 * New theory SupInf of the supremum and infimum operators for sets of
  2871 reals.
  2872 
  2873 * New theory Probability, which contains a development of measure
  2874 theory, eventually leading to Lebesgue integration and probability.
  2875 
  2876 * Extended Multivariate Analysis to include derivation and Brouwer's
  2877 fixpoint theorem.
  2878 
  2879 * Reorganization of number theory, INCOMPATIBILITY:
  2880   - new number theory development for nat and int, in theories Divides
  2881     and GCD as well as in new session Number_Theory
  2882   - some constants and facts now suffixed with _nat and _int
  2883     accordingly
  2884   - former session NumberTheory now named Old_Number_Theory, including
  2885     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2886   - moved theory Pocklington from src/HOL/Library to
  2887     src/HOL/Old_Number_Theory
  2888 
  2889 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2890 lcm of finite and infinite sets. It is shown that they form a complete
  2891 lattice.
  2892 
  2893 * Class semiring_div requires superclass no_zero_divisors and proof of
  2894 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2895 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2896 generalized to class semiring_div, subsuming former theorems
  2897 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2898 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2899 INCOMPATIBILITY.
  2900 
  2901 * Refinements to lattice classes and sets:
  2902   - less default intro/elim rules in locale variant, more default
  2903     intro/elim rules in class variant: more uniformity
  2904   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2905     le_inf_iff
  2906   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2907     sup_aci)
  2908   - renamed ACI to inf_sup_aci
  2909   - new class "boolean_algebra"
  2910   - class "complete_lattice" moved to separate theory
  2911     "Complete_Lattice"; corresponding constants (and abbreviations)
  2912     renamed and with authentic syntax:
  2913     Set.Inf ~>    Complete_Lattice.Inf
  2914     Set.Sup ~>    Complete_Lattice.Sup
  2915     Set.INFI ~>   Complete_Lattice.INFI
  2916     Set.SUPR ~>   Complete_Lattice.SUPR
  2917     Set.Inter ~>  Complete_Lattice.Inter
  2918     Set.Union ~>  Complete_Lattice.Union
  2919     Set.INTER ~>  Complete_Lattice.INTER
  2920     Set.UNION ~>  Complete_Lattice.UNION
  2921   - authentic syntax for
  2922     Set.Pow
  2923     Set.image
  2924   - mere abbreviations:
  2925     Set.empty               (for bot)
  2926     Set.UNIV                (for top)
  2927     Set.inter               (for inf, formerly Set.Int)
  2928     Set.union               (for sup, formerly Set.Un)
  2929     Complete_Lattice.Inter  (for Inf)
  2930     Complete_Lattice.Union  (for Sup)
  2931     Complete_Lattice.INTER  (for INFI)
  2932     Complete_Lattice.UNION  (for SUPR)
  2933   - object-logic definitions as far as appropriate
  2934 
  2935 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2936 Un_subset_iff are explicitly deleted as default simp rules; then also
  2937 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2938 deleted to achieve the desired effect.
  2939 
  2940 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2941 rules by default any longer; the same applies to min_max.inf_absorb1
  2942 etc.  INCOMPATIBILITY.
  2943 
  2944 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2945 pred_set_conv by default.  INCOMPATIBILITY.
  2946 
  2947 * Power operations on relations and functions are now one dedicated
  2948 constant "compow" with infix syntax "^^".  Power operation on
  2949 multiplicative monoids retains syntax "^" and is now defined generic
  2950 in class power.  INCOMPATIBILITY.
  2951 
  2952 * Relation composition "R O S" now has a more standard argument order:
  2953 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2954 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2955 break, since the O_assoc rule was not rewritten like this.  Fix using
  2956 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2957 
  2958 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2959 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2960 INCOMPATIBILITY.
  2961 
  2962 * Most rules produced by inductive and datatype package have mandatory
  2963 prefixes.  INCOMPATIBILITY.
  2964 
  2965 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2966 the attribute of the same name.  Each of the theorems in the list
  2967 DERIV_intros assumes composition with an additional function and
  2968 matches a variable to the derivative, which has to be solved by the
  2969 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2970 of most elementary terms.  Former Maclauren.DERIV_tac and
  2971 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2972 INCOMPATIBILITY.
  2973 
  2974 * Code generator attributes follow the usual underscore convention:
  2975     code_unfold     replaces    code unfold
  2976     code_post       replaces    code post
  2977     etc.
  2978   INCOMPATIBILITY.
  2979 
  2980 * Renamed methods:
  2981     sizechange -> size_change
  2982     induct_scheme -> induction_schema
  2983   INCOMPATIBILITY.
  2984 
  2985 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2986 INCOMPATIBILITY, use "undefined" directly.
  2987 
  2988 * Renamed theorems:
  2989     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2990     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2991     Suc_plus1 -> Suc_eq_plus1
  2992     *anti_sym -> *antisym*
  2993     vector_less_eq_def -> vector_le_def
  2994   INCOMPATIBILITY.
  2995 
  2996 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2997 INCOMPATIBILITY.
  2998 
  2999 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  3000 INCOMPATIBILITY.
  3001 
  3002 
  3003 *** HOLCF ***
  3004 
  3005 * Theory Representable defines a class "rep" of domains that are
  3006 representable (via an ep-pair) in the universal domain type "udom".
  3007 Instances are provided for all type constructors defined in HOLCF.
  3008 
  3009 * The 'new_domain' command is a purely definitional version of the
  3010 domain package, for representable domains.  Syntax is identical to the
  3011 old domain package.  The 'new_domain' package also supports indirect
  3012 recursion using previously-defined type constructors.  See
  3013 src/HOLCF/ex/New_Domain.thy for examples.
  3014 
  3015 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  3016 on the left-hand side of an equation, and then performs
  3017 simplification.  Rewriting is done using rules declared with the
  3018 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  3019 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  3020 
  3021 * The pattern-match compiler in 'fixrec' can now handle constructors
  3022 with HOL function types.  Pattern-match combinators for the Pair
  3023 constructor are pre-configured.
  3024 
  3025 * The 'fixrec' package now produces better fixed-point induction rules
  3026 for mutually-recursive definitions:  Induction rules have conclusions
  3027 of the form "P foo bar" instead of "P <foo, bar>".
  3028 
  3029 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  3030 been renamed to "below".  The name "below" now replaces "less" in many
  3031 theorem names.  (Legacy theorem names using "less" are still supported
  3032 as well.)
  3033 
  3034 * The 'fixrec' package now supports "bottom patterns".  Bottom
  3035 patterns can be used to generate strictness rules, or to make
  3036 functions more strict (much like the bang-patterns supported by the
  3037 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  3038 examples.
  3039 
  3040 
  3041 *** ML ***
  3042 
  3043 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  3044 errors and run-time exceptions, including detailed source positions.
  3045 
  3046 * Structure Name_Space (formerly NameSpace) now manages uniquely
  3047 identified entries, with some additional information such as source
  3048 position, logical grouping etc.
  3049 
  3050 * Theory and context data is now introduced by the simplified and
  3051 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  3052 to be pure, but the old TheoryDataFun for mutable data (with explicit
  3053 copy operation) is still available for some time.
  3054 
  3055 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  3056 provides a high-level programming interface to synchronized state
  3057 variables with atomic update.  This works via pure function
  3058 application within a critical section -- its runtime should be as
  3059 short as possible; beware of deadlocks if critical code is nested,
  3060 either directly or indirectly via other synchronized variables!
  3061 
  3062 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  3063 wraps raw ML references, explicitly indicating their non-thread-safe
  3064 behaviour.  The Isar toplevel keeps this structure open, to
  3065 accommodate Proof General as well as quick and dirty interactive
  3066 experiments with references.
  3067 
  3068 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  3069 parallel tactical reasoning.
  3070 
  3071 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  3072 are similar to SUBPROOF, but are slightly more flexible: only the
  3073 specified parts of the subgoal are imported into the context, and the
  3074 body tactic may introduce new subgoals and schematic variables.
  3075 
  3076 * Old tactical METAHYPS, which does not observe the proof context, has
  3077 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  3078 or Subgoal.FOCUS etc.
  3079 
  3080 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  3081 functors have their own ML name space there is no point to mark them
  3082 separately.)  Minor INCOMPATIBILITY.
  3083 
  3084 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  3085 
  3086 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  3087 INCOMPATIBILITY.
  3088 
  3089 * Operations of structure Skip_Proof no longer require quick_and_dirty
  3090 mode, which avoids critical setmp.
  3091 
  3092 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  3093 combinators for "args".  INCOMPATIBILITY, need to use simplified
  3094 Attrib/Method.setup introduced in Isabelle2009.
  3095 
  3096 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  3097 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  3098 last resort.  INCOMPATIBILITY.
  3099 
  3100 * Display.pretty_thm now requires a proper context (cf. former
  3101 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  3102 or even Display.pretty_thm_without_context as last resort.
  3103 INCOMPATIBILITY.
  3104 
  3105 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  3106 Syntax.pretty_typ/term directly, preferably with proper context
  3107 instead of global theory.
  3108 
  3109 
  3110 *** System ***
  3111 
  3112 * Further fine tuning of parallel proof checking, scales up to 8 cores
  3113 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  3114 usedir option -q.
  3115 
  3116 * Support for additional "Isabelle components" via etc/components, see
  3117 also the system manual.
  3118 
  3119 * The isabelle makeall tool now operates on all components with
  3120 IsaMakefile, not just hardwired "logics".
  3121 
  3122 * Removed "compress" option from isabelle-process and isabelle usedir;
  3123 this is always enabled.
  3124 
  3125 * Discontinued support for Poly/ML 4.x versions.
  3126 
  3127 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  3128 on a given logic image.  This requires the lighttpd webserver and is
  3129 currently supported on Linux only.
  3130 
  3131 
  3132 
  3133 New in Isabelle2009 (April 2009)
  3134 --------------------------------
  3135 
  3136 *** General ***
  3137 
  3138 * Simplified main Isabelle executables, with less surprises on
  3139 case-insensitive file-systems (such as Mac OS).
  3140 
  3141   - The main Isabelle tool wrapper is now called "isabelle" instead of
  3142     "isatool."
  3143 
  3144   - The former "isabelle" alias for "isabelle-process" has been
  3145     removed (should rarely occur to regular users).
  3146 
  3147   - The former "isabelle-interface" and its alias "Isabelle" have been
  3148     removed (interfaces are now regular Isabelle tools).
  3149 
  3150 Within scripts and make files, the Isabelle environment variables
  3151 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  3152 respectively.  (The latter are still available as legacy feature.)
  3153 
  3154 The old isabelle-interface wrapper could react in confusing ways if
  3155 the interface was uninstalled or changed otherwise.  Individual
  3156 interface tool configuration is now more explicit, see also the
  3157 Isabelle system manual.  In particular, Proof General is now available
  3158 via "isabelle emacs".
  3159 
  3160 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  3161 purge installed copies of Isabelle executables and re-run "isabelle
  3162 install -p ...", or use symlinks.
  3163 
  3164 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  3165 old ~/isabelle, which was slightly non-standard and apt to cause
  3166 surprises on case-insensitive file-systems (such as Mac OS).
  3167 
  3168 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  3169 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  3170 care is required when using older releases of Isabelle.  Note that
  3171 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  3172 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  3173 
  3174 * Proofs of fully specified statements are run in parallel on
  3175 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  3176 a regular 4-core machine, if the initial heap space is made reasonably
  3177 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  3178 
  3179 * The main reference manuals ("isar-ref", "implementation", and
  3180 "system") have been updated and extended.  Formally checked references
  3181 as hyperlinks are now available uniformly.
  3182 
  3183 
  3184 *** Pure ***
  3185 
  3186 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  3187 respects.  The most important changes are listed below.  See the
  3188 Tutorial on Locales ("locales" manual) for details.
  3189 
  3190 - In locale expressions, instantiation replaces renaming.  Parameters
  3191 must be declared in a for clause.  To aid compatibility with previous
  3192 parameter inheritance, in locale declarations, parameters that are not
  3193 'touched' (instantiation position "_" or omitted) are implicitly added
  3194 with their syntax at the beginning of the for clause.
  3195 
  3196 - Syntax from abbreviations and definitions in locales is available in
  3197 locale expressions and context elements.  The latter is particularly
  3198 useful in locale declarations.
  3199 
  3200 - More flexible mechanisms to qualify names generated by locale
  3201 expressions.  Qualifiers (prefixes) may be specified in locale
  3202 expressions, and can be marked as mandatory (syntax: "name!:") or
  3203 optional (syntax "name?:").  The default depends for plain "name:"
  3204 depends on the situation where a locale expression is used: in
  3205 commands 'locale' and 'sublocale' prefixes are optional, in
  3206 'interpretation' and 'interpret' prefixes are mandatory.  The old
  3207 implicit qualifiers derived from the parameter names of a locale are
  3208 no longer generated.
  3209 
  3210 - Command "sublocale l < e" replaces "interpretation l < e".  The
  3211 instantiation clause in "interpretation" and "interpret" (square
  3212 brackets) is no longer available.  Use locale expressions.
  3213 
  3214 - When converting proof scripts, mandatory qualifiers in
  3215 'interpretation' and 'interpret' should be retained by default, even
  3216 if this is an INCOMPATIBILITY compared to former behavior.  In the
  3217 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  3218 in locale expressions range over a single locale instance only.
  3219 
  3220 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  3221 In existing theorem specifications replace the includes element by the
  3222 respective context elements of the included locale, omitting those
  3223 that are already present in the theorem specification.  Multiple
  3224 assume elements of a locale should be replaced by a single one
  3225 involving the locale predicate.  In the proof body, declarations (most
  3226 notably theorems) may be regained by interpreting the respective
  3227 locales in the proof context as required (command "interpret").
  3228 
  3229 If using "includes" in replacement of a target solely because the
  3230 parameter types in the theorem are not as general as in the target,
  3231 consider declaring a new locale with additional type constraints on
  3232 the parameters (context element "constrains").
  3233 
  3234 - Discontinued "locale (open)".  INCOMPATIBILITY.
  3235 
  3236 - Locale interpretation commands no longer attempt to simplify goal.
  3237 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  3238 methods intro_locales and unfold_locales to clarify.
  3239 
  3240 - Locale interpretation commands no longer accept interpretation
  3241 attributes.  INCOMPATIBILITY.
  3242 
  3243 * Class declaration: so-called "base sort" must not be given in import
  3244 list any longer, but is inferred from the specification.  Particularly
  3245 in HOL, write
  3246 
  3247     class foo = ...
  3248 
  3249 instead of
  3250 
  3251     class foo = type + ...
  3252 
  3253 * Class target: global versions of theorems stemming do not carry a
  3254 parameter prefix any longer.  INCOMPATIBILITY.
  3255 
  3256 * Class 'instance' command no longer accepts attached definitions.
  3257 INCOMPATIBILITY, use proper 'instantiation' target instead.
  3258 
  3259 * Recovered hiding of consts, which was accidentally broken in
  3260 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  3261 makes c inaccessible; consider using ``hide (open) const c'' instead.
  3262 
  3263 * Slightly more coherent Pure syntax, with updated documentation in
  3264 isar-ref manual.  Removed locales meta_term_syntax and
  3265 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  3266 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  3267 directly in regular applications.
  3268 
  3269 * There is a new syntactic category "float_const" for signed decimal
  3270 fractions (e.g. 123.45 or -123.45).
  3271 
  3272 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  3273 interface with 'setup' command instead.
  3274 
  3275 * Command 'local_setup' is similar to 'setup', but operates on a local
  3276 theory context.
  3277 
  3278 * The 'axiomatization' command now only works within a global theory
  3279 context.  INCOMPATIBILITY.
  3280 
  3281 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  3282 hypotheses.  Sorts required in the course of reasoning need to be
  3283 covered by the constraints in the initial statement, completed by the
  3284 type instance information of the background theory.  Non-trivial sort
  3285 hypotheses, which rarely occur in practice, may be specified via
  3286 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  3287 
  3288   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  3289 
  3290 The result contains an implicit sort hypotheses as before --
  3291 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  3292 normalization.
  3293 
  3294 * Generalized Isar history, with support for linear undo, direct state
  3295 addressing etc.
  3296 
  3297 * Changed defaults for unify configuration options:
  3298 
  3299   unify_trace_bound = 50 (formerly 25)
  3300   unify_search_bound = 60 (formerly 30)
  3301 
  3302 * Different bookkeeping for code equations (INCOMPATIBILITY):
  3303 
  3304   a) On theory merge, the last set of code equations for a particular
  3305      constant is taken (in accordance with the policy applied by other
  3306      parts of the code generator framework).
  3307 
  3308   b) Code equations stemming from explicit declarations (e.g. code
  3309      attribute) gain priority over default code equations stemming
  3310      from definition, primrec, fun etc.
  3311 
  3312 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  3313 
  3314 * Unified theorem tables for both code generators.  Thus [code
  3315 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  3316 
  3317 * Command 'find_consts' searches for constants based on type and name
  3318 patterns, e.g.
  3319 
  3320     find_consts "_ => bool"
  3321 
  3322 By default, matching is against subtypes, but it may be restricted to
  3323 the whole type.  Searching by name is possible.  Multiple queries are
  3324 conjunctive and queries may be negated by prefixing them with a
  3325 hyphen:
  3326 
  3327     find_consts strict: "_ => bool" name: "Int" -"int => int"
  3328 
  3329 * New 'find_theorems' criterion "solves" matches theorems that
  3330 directly solve the current goal (modulo higher-order unification).
  3331 
  3332 * Auto solve feature for main theorem statements: whenever a new goal
  3333 is stated, "find_theorems solves" is called; any theorems that could
  3334 solve the lemma directly are listed as part of the goal state.
  3335 Cf. associated options in Proof General Isabelle settings menu,
  3336 enabled by default, with reasonable timeout for pathological cases of
  3337 higher-order unification.
  3338 
  3339 
  3340 *** Document preparation ***
  3341 
  3342 * Antiquotation @{lemma} now imitates a regular terminal proof,
  3343 demanding keyword 'by' and supporting the full method expression
  3344 syntax just like the Isar command 'by'.
  3345 
  3346 
  3347 *** HOL ***
  3348 
  3349 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  3350 points Main and Complex_Main remain as before.
  3351 
  3352 * Logic image HOL-Plain provides a minimal HOL with the most important
  3353 tools available (inductive, datatype, primrec, ...).  This facilitates
  3354 experimentation and tool development.  Note that user applications
  3355 (and library theories) should never refer to anything below theory
  3356 Main, as before.
  3357 
  3358 * Logic image HOL-Main stops at theory Main, and thus facilitates
  3359 experimentation due to shorter build times.
  3360 
  3361 * Logic image HOL-NSA contains theories of nonstandard analysis which
  3362 were previously part of former HOL-Complex.  Entry point Hyperreal
  3363 remains valid, but theories formerly using Complex_Main should now use
  3364 new entry point Hypercomplex.
  3365 
  3366 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  3367 Posix processes.  Avoids potentially expensive forking of the ML
  3368 process.  New thread-based implementation also works on non-Unix
  3369 platforms (Cygwin).  Provers are no longer hardwired, but defined
  3370 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  3371 commands are covered in the isar-ref manual.
  3372 
  3373 * Wrapper scripts for remote SystemOnTPTP service allows to use
  3374 sledgehammer without local ATP installation (Vampire etc.). Other
  3375 provers may be included via suitable ML wrappers, see also
  3376 src/HOL/ATP_Linkup.thy.
  3377 
  3378 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  3379 menu.
  3380 
  3381 * The metis method no longer fails because the theorem is too trivial
  3382 (contains the empty clause).
  3383 
  3384 * The metis method now fails in the usual manner, rather than raising
  3385 an exception, if it determines that it cannot prove the theorem.
  3386 
  3387 * Method "coherent" implements a prover for coherent logic (see also
  3388 src/Tools/coherent.ML).
  3389 
  3390 * Constants "undefined" and "default" replace "arbitrary".  Usually
  3391 "undefined" is the right choice to replace "arbitrary", though
  3392 logically there is no difference.  INCOMPATIBILITY.
  3393 
  3394 * Command "value" now integrates different evaluation mechanisms.  The
  3395 result of the first successful evaluation mechanism is printed.  In
  3396 square brackets a particular named evaluation mechanisms may be
  3397 specified (currently, [SML], [code] or [nbe]).  See further
  3398 src/HOL/ex/Eval_Examples.thy.
  3399 
  3400 * Normalization by evaluation now allows non-leftlinear equations.
  3401 Declare with attribute [code nbe].
  3402 
  3403 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  3404 as the structured Isar versions "cases" and "induct", cf. the
  3405 corresponding "cases" and "induct" attributes.  Mutual induction rules
  3406 are now presented as a list of individual projections
  3407 (e.g. foo_bar.inducts for types foo and bar); the old format with
  3408 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  3409 rare situations a different rule is selected --- notably nested tuple
  3410 elimination instead of former prod.exhaust: use explicit (case_tac t
  3411 rule: prod.exhaust) here.
  3412 
  3413 * Attributes "cases", "induct", "coinduct" support "del" option.
  3414 
  3415 * Removed fact "case_split_thm", which duplicates "case_split".
  3416 
  3417 * The option datatype has been moved to a new theory Option.  Renamed
  3418 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  3419 
  3420 * New predicate "strict_mono" classifies strict functions on partial
  3421 orders.  With strict functions on linear orders, reasoning about
  3422 (in)equalities is facilitated by theorems "strict_mono_eq",
  3423 "strict_mono_less_eq" and "strict_mono_less".
  3424 
  3425 * Some set operations are now proper qualified constants with
  3426 authentic syntax.  INCOMPATIBILITY:
  3427 
  3428     op Int ~>   Set.Int
  3429     op Un ~>    Set.Un
  3430     INTER ~>    Set.INTER
  3431     UNION ~>    Set.UNION
  3432     Inter ~>    Set.Inter
  3433     Union ~>    Set.Union
  3434     {} ~>       Set.empty
  3435     UNIV ~>     Set.UNIV
  3436 
  3437 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  3438 theory Set.
  3439 
  3440 * Auxiliary class "itself" has disappeared -- classes without any
  3441 parameter are treated as expected by the 'class' command.
  3442 
  3443 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  3444 
  3445 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  3446 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  3447 
  3448 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  3449 method "approximation".  It proves formulas on real values by using
  3450 interval arithmetic.  In the formulas are also the transcendental
  3451 functions sin, cos, tan, atan, ln, exp and the constant pi are
  3452 allowed. For examples see
  3453 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  3454 
  3455 * Theory "Reflection" now resides in HOL/Library.
  3456 
  3457 * Entry point to Word library now simply named "Word".
  3458 INCOMPATIBILITY.
  3459 
  3460 * Made source layout more coherent with logical distribution
  3461 structure:
  3462 
  3463     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  3464     src/HOL/Library/Code_Message.thy ~> src/HOL/
  3465     src/HOL/Library/GCD.thy ~> src/HOL/
  3466     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  3467     src/HOL/Library/Parity.thy ~> src/HOL/
  3468     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  3469     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  3470     src/HOL/Real/Lubs.thy ~> src/HOL/
  3471     src/HOL/Real/PReal.thy ~> src/HOL/
  3472     src/HOL/Real/Rational.thy ~> src/HOL/
  3473     src/HOL/Real/RComplete.thy ~> src/HOL/
  3474     src/HOL/Real/RealDef.thy ~> src/HOL/
  3475     src/HOL/Real/RealPow.thy ~> src/HOL/
  3476     src/HOL/Real/Real.thy ~> src/HOL/
  3477     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  3478     src/HOL/Complex/Complex.thy ~> src/HOL/
  3479     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  3480     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  3481     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  3482     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  3483     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  3484     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  3485     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  3486     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  3487     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  3488     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  3489     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  3490     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  3491     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  3492     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  3493     src/HOL/Real/Float ~> src/HOL/Library/
  3494     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  3495     src/HOL/Real/RealVector.thy ~> src/HOL/
  3496 
  3497     src/HOL/arith_data.ML ~> src/HOL/Tools
  3498     src/HOL/hologic.ML ~> src/HOL/Tools
  3499     src/HOL/simpdata.ML ~> src/HOL/Tools
  3500     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3501     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3502     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3503     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3504     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3505     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3506     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3507 
  3508     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3509     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3510     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3511     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3512     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3513     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3514 
  3515 * If methods "eval" and "evaluation" encounter a structured proof
  3516 state with !!/==>, only the conclusion is evaluated to True (if
  3517 possible), avoiding strange error messages.
  3518 
  3519 * Method "sizechange" automates termination proofs using (a
  3520 modification of) the size-change principle.  Requires SAT solver.  See
  3521 src/HOL/ex/Termination.thy for examples.
  3522 
  3523 * Simplifier: simproc for let expressions now unfolds if bound
  3524 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3525 
  3526 * Method "arith": Linear arithmetic now ignores all inequalities when
  3527 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3528 
  3529 * New attribute "arith" for facts that should always be used
  3530 automatically by arithmetic. It is intended to be used locally in
  3531 proofs, e.g.
  3532 
  3533   assumes [arith]: "x > 0"
  3534 
  3535 Global usage is discouraged because of possible performance impact.
  3536 
  3537 * New classes "top" and "bot" with corresponding operations "top" and
  3538 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3539 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3540 
  3541 * Changed definition lemma "less_fun_def" in order to provide an
  3542 instance for preorders on functions; use lemma "less_le" instead.
  3543 INCOMPATIBILITY.
  3544 
  3545 * Theory Orderings: class "wellorder" moved here, with explicit
  3546 induction rule "less_induct" as assumption.  For instantiation of
  3547 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3548 INCOMPATIBILITY.
  3549 
  3550 * Theory Orderings: added class "preorder" as superclass of "order".
  3551 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3552 etc. slightly changed.  Some theorems named order_class.* now named
  3553 preorder_class.*.
  3554 
  3555 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3556 "diag" to "Id_on".
  3557 
  3558 * Theory Finite_Set: added a new fold combinator of type
  3559 
  3560   ('a => 'b => 'b) => 'b => 'a set => 'b
  3561 
  3562 Occasionally this is more convenient than the old fold combinator
  3563 which is now defined in terms of the new one and renamed to
  3564 fold_image.
  3565 
  3566 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3567 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3568 extended with further lemmas!).  At the moment both still exist but
  3569 the former will disappear at some point.
  3570 
  3571 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3572 class recpower.  Type-specific simp rules for various recpower types
  3573 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3574 
  3575 rat_power_0    -> power_0
  3576 rat_power_Suc  -> power_Suc
  3577 realpow_0      -> power_0
  3578 realpow_Suc    -> power_Suc
  3579 complexpow_0   -> power_0
  3580 complexpow_Suc -> power_Suc
  3581 power_poly_0   -> power_0
  3582 power_poly_Suc -> power_Suc
  3583 
  3584 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3585 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3586 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3587 of lemmas from Divides has been generalized from nat to class
  3588 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3589 renames resulting from duplicate elimination:
  3590 
  3591     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3592     zero_dvd_iff ~>         dvd_0_left_iff
  3593     dvd_0 ~>                dvd_0_right
  3594     DIVISION_BY_ZERO_DIV ~> div_by_0
  3595     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3596     mult_div ~>             div_mult_self2_is_id
  3597     mult_mod ~>             mod_mult_self2_is_0
  3598 
  3599 * Theory IntDiv: removed many lemmas that are instances of class-based
  3600 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3601 rename old lemmas as follows:
  3602 
  3603 dvd_diff               -> nat_dvd_diff
  3604 dvd_zminus_iff         -> dvd_minus_iff
  3605 mod_add1_eq            -> mod_add_eq
  3606 mod_mult1_eq           -> mod_mult_right_eq
  3607 mod_mult1_eq'          -> mod_mult_left_eq
  3608 mod_mult_distrib_mod   -> mod_mult_eq
  3609 nat_mod_add_left_eq    -> mod_add_left_eq
  3610 nat_mod_add_right_eq   -> mod_add_right_eq
  3611 nat_mod_div_trivial    -> mod_div_trivial
  3612 nat_mod_mod_trivial    -> mod_mod_trivial
  3613 zdiv_zadd_self1        -> div_add_self1
  3614 zdiv_zadd_self2        -> div_add_self2
  3615 zdiv_zmult_self1       -> div_mult_self2_is_id
  3616 zdiv_zmult_self2       -> div_mult_self1_is_id
  3617 zdvd_triv_left         -> dvd_triv_left
  3618 zdvd_triv_right        -> dvd_triv_right
  3619 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3620 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3621 zmod_zadd_left_eq      -> mod_add_left_eq
  3622 zmod_zadd_right_eq     -> mod_add_right_eq
  3623 zmod_zadd_self1        -> mod_add_self1
  3624 zmod_zadd_self2        -> mod_add_self2
  3625 zmod_zadd1_eq          -> mod_add_eq
  3626 zmod_zdiff1_eq         -> mod_diff_eq
  3627 zmod_zdvd_zmod         -> mod_mod_cancel
  3628 zmod_zmod_cancel       -> mod_mod_cancel
  3629 zmod_zmult_self1       -> mod_mult_self2_is_0
  3630 zmod_zmult_self2       -> mod_mult_self1_is_0
  3631 zmod_1                 -> mod_by_1
  3632 zdiv_1                 -> div_by_1
  3633 zdvd_abs1              -> abs_dvd_iff
  3634 zdvd_abs2              -> dvd_abs_iff
  3635 zdvd_refl              -> dvd_refl
  3636 zdvd_trans             -> dvd_trans
  3637 zdvd_zadd              -> dvd_add
  3638 zdvd_zdiff             -> dvd_diff
  3639 zdvd_zminus_iff        -> dvd_minus_iff
  3640 zdvd_zminus2_iff       -> minus_dvd_iff
  3641 zdvd_zmultD            -> dvd_mult_right
  3642 zdvd_zmultD2           -> dvd_mult_left
  3643 zdvd_zmult_mono        -> mult_dvd_mono
  3644 zdvd_0_right           -> dvd_0_right
  3645 zdvd_0_left            -> dvd_0_left_iff
  3646 zdvd_1_left            -> one_dvd
  3647 zminus_dvd_iff         -> minus_dvd_iff
  3648 
  3649 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3650 
  3651 * The real numbers offer decimal input syntax: 12.34 is translated
  3652 into 1234/10^2. This translation is not reversed upon output.
  3653 
  3654 * Theory Library/Polynomial defines an abstract type 'a poly of
  3655 univariate polynomials with coefficients of type 'a.  In addition to
  3656 the standard ring operations, it also supports div and mod.  Code
  3657 generation is also supported, using list-style constructors.
  3658 
  3659 * Theory Library/Inner_Product defines a class of real_inner for real
  3660 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3661 => real.  Class real_inner is a subclass of real_normed_vector from
  3662 theory RealVector.
  3663 
  3664 * Theory Library/Product_Vector provides instances for the product
  3665 type 'a * 'b of several classes from RealVector and Inner_Product.
  3666 Definitions of addition, subtraction, scalar multiplication, norms,
  3667 and inner products are included.
  3668 
  3669 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3670 addition to the field operations, numerals and case syntax are also
  3671 supported.
  3672 
  3673 * Theory Library/Diagonalize provides constructive version of Cantor's
  3674 first diagonalization argument.
  3675 
  3676 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3677 zlcm (for int); carried together from various gcd/lcm developements in
  3678 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3679 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3680 may recover tupled syntax as follows:
  3681 
  3682     hide (open) const gcd
  3683     abbreviation gcd where
  3684       "gcd == (%(a, b). GCD.gcd a b)"
  3685     notation (output)
  3686       GCD.gcd ("gcd '(_, _')")
  3687 
  3688 The same works for lcm, zgcd, zlcm.
  3689 
  3690 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3691 instantiations for algebraic structures.  Removed some duplicate
  3692 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3693 
  3694 * ML antiquotation @{code} takes a constant as argument and generates
  3695 corresponding code in background and inserts name of the corresponding
  3696 resulting ML value/function/datatype constructor binding in place.
  3697 All occurrences of @{code} with a single ML block are generated
  3698 simultaneously.  Provides a generic and safe interface for
  3699 instrumentalizing code generation.  See
  3700 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3701 In future you ought to refrain from ad-hoc compiling generated SML
  3702 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3703 cannot refer to constants for which user-defined serializations are
  3704 set.  Refer to the corresponding ML counterpart directly in that
  3705 cases.
  3706 
  3707 * Command 'rep_datatype': instead of theorem names the command now
  3708 takes a list of terms denoting the constructors of the type to be
  3709 represented as datatype.  The characteristic theorems have to be
  3710 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3711 have disappeared in favour of existing ones:
  3712 
  3713     unit_induct                 ~> unit.induct
  3714     prod_induct                 ~> prod.induct
  3715     sum_induct                  ~> sum.induct
  3716     Suc_Suc_eq                  ~> nat.inject
  3717     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3718 
  3719 
  3720 *** HOL-Algebra ***
  3721 
  3722 * New locales for orders and lattices where the equivalence relation
  3723 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3724 locales use a record structure with field eq for the equivalence.
  3725 
  3726 * New theory of factorial domains.
  3727 
  3728 * Units_l_inv and Units_r_inv are now simp rules by default.
  3729 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3730 and/or r_inv will now also require deletion of these lemmas.
  3731 
  3732 * Renamed the following theorems, INCOMPATIBILITY:
  3733 
  3734 UpperD ~> Upper_memD
  3735 LowerD ~> Lower_memD
  3736 least_carrier ~> least_closed
  3737 greatest_carrier ~> greatest_closed
  3738 greatest_Lower_above ~> greatest_Lower_below
  3739 one_zero ~> carrier_one_zero
  3740 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3741 
  3742 
  3743 *** HOL-Nominal ***
  3744 
  3745 * Nominal datatypes can now contain type-variables.
  3746 
  3747 * Commands 'nominal_inductive' and 'equivariance' work with local
  3748 theory targets.
  3749 
  3750 * Nominal primrec can now works with local theory targets and its
  3751 specification syntax now conforms to the general format as seen in
  3752 'inductive' etc.
  3753 
  3754 * Method "perm_simp" honours the standard simplifier attributes
  3755 (no_asm), (no_asm_use) etc.
  3756 
  3757 * The new predicate #* is defined like freshness, except that on the
  3758 left hand side can be a set or list of atoms.
  3759 
  3760 * Experimental command 'nominal_inductive2' derives strong induction
  3761 principles for inductive definitions.  In contrast to
  3762 'nominal_inductive', which can only deal with a fixed number of
  3763 binders, it can deal with arbitrary expressions standing for sets of
  3764 atoms to be avoided.  The only inductive definition we have at the
  3765 moment that needs this generalisation is the typing rule for Lets in
  3766 the algorithm W:
  3767 
  3768  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3769  -----------------------------------------------------------------
  3770          Gamma |- Let x be t1 in t2 : T2
  3771 
  3772 In this rule one wants to avoid all the binders that are introduced by
  3773 "close Gamma T1".  We are looking for other examples where this
  3774 feature might be useful.  Please let us know.
  3775 
  3776 
  3777 *** HOLCF ***
  3778 
  3779 * Reimplemented the simplification procedure for proving continuity
  3780 subgoals.  The new simproc is extensible; users can declare additional
  3781 continuity introduction rules with the attribute [cont2cont].
  3782 
  3783 * The continuity simproc now uses a different introduction rule for
  3784 solving continuity subgoals on terms with lambda abstractions.  In
  3785 some rare cases the new simproc may fail to solve subgoals that the
  3786 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3787 Potential INCOMPATIBILITY.
  3788 
  3789 * Command 'fixrec': specification syntax now conforms to the general
  3790 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3791 examples.  INCOMPATIBILITY.
  3792 
  3793 
  3794 *** ZF ***
  3795 
  3796 * Proof of Zorn's Lemma for partial orders.
  3797 
  3798 
  3799 *** ML ***
  3800 
  3801 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3802 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3803 depends on multithreading, so timouts will not work before Poly/ML
  3804 5.2.1!
  3805 
  3806 * High-level support for concurrent ML programming, see
  3807 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3808 particularly convenient to organize independent functional
  3809 computations.  The concept of "synchronized variables" provides a
  3810 higher-order interface for components with shared state, avoiding the
  3811 delicate details of mutexes and condition variables.  (Requires
  3812 Poly/ML 5.2.1 or later.)
  3813 
  3814 * ML bindings produced via Isar commands are stored within the Isar
  3815 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3816 become thread-safe and work with undo as expected (concerning
  3817 top-level bindings, not side-effects on global references).
  3818 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3819 compiler at runtime; really global bindings need to be given outside a
  3820 theory.  (Requires Poly/ML 5.2 or later.)
  3821 
  3822 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3823 context.  Top-level ML bindings are stored within the proof context in
  3824 a purely sequential fashion, disregarding the nested proof structure.
  3825 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3826 proof.  (Requires Poly/ML 5.2 or later.)
  3827 
  3828 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3829 and Method.setup, as well as Isar commands 'attribute_setup' and
  3830 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3831 existing code accordingly, or use plain 'setup' together with old
  3832 Method.add_method.
  3833 
  3834 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3835 to 'a -> thm, while results are always tagged with an authentic oracle
  3836 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3837 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3838 accordingly.  Note that extra performance may be gained by producing
  3839 the cterm carefully, avoiding slow Thm.cterm_of.
  3840 
  3841 * Simplified interface for defining document antiquotations via
  3842 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3843 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3844 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3845 examples.
  3846 
  3847 * More systematic treatment of long names, abstract name bindings, and
  3848 name space operations.  Basic operations on qualified names have been
  3849 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3850 Long_Name.append.  Old type bstring has been mostly replaced by
  3851 abstract type binding (see structure Binding), which supports precise
  3852 qualification by packages and local theory targets, as well as proper
  3853 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3854 bstring values into Binding.name, or better pass through abstract
  3855 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3856 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3857 
  3858 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3859 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3860 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3861 
  3862 * Disposed old type and term read functions (Sign.read_def_typ,
  3863 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3864 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3865 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3866 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3867 resort for legacy applications.
  3868 
  3869 * Disposed old declarations, tactics, tactic combinators that refer to
  3870 the simpset or claset of an implicit theory (such as Addsimps,
  3871 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3872 embedded ML text, or local_simpset_of with a proper context passed as
  3873 explicit runtime argument.
  3874 
  3875 * Rules and tactics that read instantiations (read_instantiate,
  3876 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3877 context, which is required for parsing and type-checking.  Moreover,
  3878 the variables are specified as plain indexnames, not string encodings
  3879 thereof.  INCOMPATIBILITY.
  3880 
  3881 * Generic Toplevel.add_hook interface allows to analyze the result of
  3882 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3883 for theorem dependency output of transactions resulting in a new
  3884 theory state.
  3885 
  3886 * ML antiquotations: block-structured compilation context indicated by
  3887 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3888 
  3889   @{binding name}                         - basic name binding
  3890   @{let ?pat = term}                      - term abbreviation (HO matching)
  3891   @{note name = fact}                     - fact abbreviation
  3892   @{thm fact}                             - singleton fact (with attributes)
  3893   @{thms fact}                            - general fact (with attributes)
  3894   @{lemma prop by method}                 - singleton goal
  3895   @{lemma prop by meth1 meth2}            - singleton goal
  3896   @{lemma prop1 ... propN by method}      - general goal
  3897   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3898   @{lemma (open) ...}                     - open derivation
  3899 
  3900 
  3901 *** System ***
  3902 
  3903 * The Isabelle "emacs" tool provides a specific interface to invoke
  3904 Proof General / Emacs, with more explicit failure if that is not
  3905 installed (the old isabelle-interface script silently falls back on
  3906 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3907 installation location of the Proof General distribution.
  3908 
  3909 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3910 the Isabelle process into a JVM/Scala application.  See
  3911 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3912 process wrapper has been discontinued.)
  3913 
  3914 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3915 
  3916 * Various status messages (with exact source position information) are
  3917 emitted, if proper markup print mode is enabled.  This allows
  3918 user-interface components to provide detailed feedback on internal
  3919 prover operations.
  3920 
  3921 
  3922 
  3923 New in Isabelle2008 (June 2008)
  3924 -------------------------------
  3925 
  3926 *** General ***
  3927 
  3928 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3929 and updated, with formally checked references as hyperlinks.
  3930 
  3931 * Theory loader: use_thy (and similar operations) no longer set the
  3932 implicit ML context, which was occasionally hard to predict and in
  3933 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3934 provides a proper context already.
  3935 
  3936 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3937 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3938 'use' within a theory file will do the job.
  3939 
  3940 * Name space merge now observes canonical order, i.e. the second space
  3941 is inserted into the first one, while existing entries in the first
  3942 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3943 swap theory imports.
  3944 
  3945 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3946 INCOMPATIBILITY in identifier syntax etc.
  3947 
  3948 * Outer syntax: string tokens no longer admit escaped white space,
  3949 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3950 white space without escapes.
  3951 
  3952 * Outer syntax: string tokens may contain arbitrary character codes
  3953 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3954 "foo_bar".
  3955 
  3956 
  3957 *** Pure ***
  3958 
  3959 * Context-dependent token translations.  Default setup reverts locally
  3960 fixed variables, and adds hilite markup for undeclared frees.
  3961 
  3962 * Unused theorems can be found using the new command 'unused_thms'.
  3963 There are three ways of invoking it:
  3964 
  3965 (1) unused_thms
  3966      Only finds unused theorems in the current theory.
  3967 
  3968 (2) unused_thms thy_1 ... thy_n -
  3969      Finds unused theorems in the current theory and all of its ancestors,
  3970      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3971 
  3972 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3973      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3974      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3975      their ancestors.
  3976 
  3977 In order to increase the readability of the list produced by
  3978 unused_thms, theorems that have been created by a particular instance
  3979 of a theory command such as 'inductive' or 'function' are considered
  3980 to belong to the same "group", meaning that if at least one theorem in
  3981 this group is used, the other theorems in the same group are no longer
  3982 reported as unused.  Moreover, if all theorems in the group are
  3983 unused, only one theorem in the group is displayed.
  3984 
  3985 Note that proof objects have to be switched on in order for
  3986 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3987 usually the case when using Proof General with the default settings).
  3988 
  3989 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3990 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3991 duplicate fact bindings, or even accidental fact duplications.  Note
  3992 that tools may maintain dynamically scoped facts systematically, using
  3993 PureThy.add_thms_dynamic.
  3994 
  3995 * Command 'hide' now allows to hide from "fact" name space as well.
  3996 
  3997 * Eliminated destructive theorem database, simpset, claset, and
  3998 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3999 update of theories within ML code.
  4000 
  4001 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  4002 INCOMPATIBILITY, object-logics depending on former Pure require
  4003 additional setup PureThy.old_appl_syntax_setup; object-logics
  4004 depending on former CPure need to refer to Pure.
  4005 
  4006 * Commands 'use' and 'ML' are now purely functional, operating on
  4007 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  4008 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  4009 INCOMPATIBILITY.
  4010 
  4011 * Command 'setup': discontinued implicit version with ML reference.
  4012 
  4013 * Instantiation target allows for simultaneous specification of class
  4014 instance operations together with an instantiation proof.
  4015 Type-checking phase allows to refer to class operations uniformly.
  4016 See src/HOL/Complex/Complex.thy for an Isar example and
  4017 src/HOL/Library/Eval.thy for an ML example.
  4018 
  4019 * Indexing of literal facts: be more serious about including only
  4020 facts from the visible specification/proof context, but not the
  4021 background context (locale etc.).  Affects `prop` notation and method
  4022 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  4023 situations.
  4024 
  4025 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  4026 "(open)" option, which used to expose internal bound variables to the
  4027 proof text.
  4028 
  4029 * Isar statements: removed obsolete case "rule_context".
  4030 INCOMPATIBILITY, better use explicit fixes/assumes.
  4031 
  4032 * Locale proofs: default proof step now includes 'unfold_locales';
  4033 hence 'proof' without argument may be used to unfold locale
  4034 predicates.
  4035 
  4036 
  4037 *** Document preparation ***
  4038 
  4039 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  4040 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  4041 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  4042 spot); renamed link color from "darkblue" to "linkcolor" (default
  4043 value unchanged, can be redefined via \definecolor); no longer sets
  4044 "a4paper" option (unnecessary or even intrusive).
  4045 
  4046 * Antiquotation @{lemma A method} proves proposition A by the given
  4047 method (either a method name or a method name plus (optional) method
  4048 arguments in parentheses) and prints A just like @{prop A}.
  4049 
  4050 
  4051 *** HOL ***
  4052 
  4053 * New primrec package.  Specification syntax conforms in style to
  4054 definition/function/....  No separate induction rule is provided.  The
  4055 "primrec" command distinguishes old-style and new-style specifications
  4056 by syntax.  The former primrec package is now named OldPrimrecPackage.
  4057 When adjusting theories, beware: constants stemming from new-style
  4058 primrec specifications have authentic syntax.
  4059 
  4060 * Metis prover is now an order of magnitude faster, and also works
  4061 with multithreading.
  4062 
  4063 * Metis: the maximum number of clauses that can be produced from a
  4064 theorem is now given by the attribute max_clauses.  Theorems that
  4065 exceed this number are ignored, with a warning printed.
  4066 
  4067 * Sledgehammer no longer produces structured proofs by default. To
  4068 enable, declare [[sledgehammer_full = true]].  Attributes
  4069 reconstruction_modulus, reconstruction_sorts renamed
  4070 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  4071 
  4072 * Method "induct_scheme" derives user-specified induction rules
  4073 from well-founded induction and completeness of patterns. This factors
  4074 out some operations that are done internally by the function package
  4075 and makes them available separately.  See
  4076 src/HOL/ex/Induction_Scheme.thy for examples.
  4077 
  4078 * More flexible generation of measure functions for termination
  4079 proofs: Measure functions can be declared by proving a rule of the
  4080 form "is_measure f" and giving it the [measure_function] attribute.
  4081 The "is_measure" predicate is logically meaningless (always true), and
  4082 just guides the heuristic.  To find suitable measure functions, the
  4083 termination prover sets up the goal "is_measure ?f" of the appropriate
  4084 type and generates all solutions by prolog-style backwards proof using
  4085 the declared rules.
  4086 
  4087 This setup also deals with rules like 
  4088 
  4089   "is_measure f ==> is_measure (list_size f)"
  4090 
  4091 which accommodates nested datatypes that recurse through lists.
  4092 Similar rules are predeclared for products and option types.
  4093 
  4094 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  4095 
  4096   INCOMPATIBILITIES:
  4097 
  4098   - Definitions of overloaded constants on sets have to be replaced by
  4099     definitions on => and bool.
  4100 
  4101   - Some definitions of overloaded operators on sets can now be proved
  4102     using the definitions of the operators on => and bool.  Therefore,
  4103     the following theorems have been renamed:
  4104 
  4105       subset_def   -> subset_eq
  4106       psubset_def  -> psubset_eq
  4107       set_diff_def -> set_diff_eq
  4108       Compl_def    -> Compl_eq
  4109       Sup_set_def  -> Sup_set_eq
  4110       Inf_set_def  -> Inf_set_eq
  4111       sup_set_def  -> sup_set_eq
  4112       inf_set_def  -> inf_set_eq
  4113 
  4114   - Due to the incompleteness of the HO unification algorithm, some
  4115     rules such as subst may require manual instantiation, if some of
  4116     the unknowns in the rule is a set.
  4117 
  4118   - Higher order unification and forward proofs:
  4119     The proof pattern
  4120 
  4121       have "P (S::'a set)" <...>
  4122       then have "EX S. P S" ..
  4123 
  4124     no longer works (due to the incompleteness of the HO unification
  4125     algorithm) and must be replaced by the pattern
  4126 
  4127       have "EX S. P S"
  4128       proof
  4129         show "P S" <...>
  4130       qed
  4131 
  4132   - Calculational reasoning with subst (or similar rules):
  4133     The proof pattern
  4134 
  4135       have "P (S::'a set)" <...>
  4136       also have "S = T" <...>
  4137       finally have "P T" .
  4138 
  4139     no longer works (for similar reasons as the previous example) and
  4140     must be replaced by something like
  4141 
  4142       have "P (S::'a set)" <...>
  4143       moreover have "S = T" <...>
  4144       ultimately have "P T" by simp
  4145 
  4146   - Tactics or packages written in ML code:
  4147     Code performing pattern matching on types via
  4148 
  4149       Type ("set", [T]) => ...
  4150 
  4151     must be rewritten. Moreover, functions like strip_type or
  4152     binder_types no longer return the right value when applied to a
  4153     type of the form
  4154 
  4155       T1 => ... => Tn => U => bool
  4156 
  4157     rather than
  4158 
  4159       T1 => ... => Tn => U set
  4160 
  4161 * Merged theories Wellfounded_Recursion, Accessible_Part and
  4162 Wellfounded_Relations to theory Wellfounded.
  4163 
  4164 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  4165 
  4166 * Class finite no longer treats UNIV as class parameter.  Use class
  4167 enum from theory Library/Enum instead to achieve a similar effect.
  4168 INCOMPATIBILITY.
  4169 
  4170 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  4171 and "Cons".  INCOMPATIBILITY.
  4172 
  4173 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  4174 Potential INCOMPATIBILITY.
  4175 
  4176 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  4177 injective_fst_snd removed, use split_eta and prod_eqI instead.
  4178 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  4179 
  4180 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  4181 the same name in theory Orderings:
  4182 
  4183   less_trans
  4184   less_linear
  4185   le_imp_less_or_eq
  4186   le_less_trans
  4187   less_le_trans
  4188   less_not_sym
  4189   less_asym
  4190 
  4191 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  4192 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  4193 and different variable names.
  4194 
  4195 * Library/Option_ord.thy: Canonical order on option type.
  4196 
  4197 * Library/RBT.thy: Red-black trees, an efficient implementation of
  4198 finite maps.
  4199 
  4200 * Library/Countable.thy: Type class for countable types.
  4201 
  4202 * Theory Int: The representation of numerals has changed.  The infix
  4203 operator BIT and the bit datatype with constructors B0 and B1 have
  4204 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  4205 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  4206 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  4207 accordingly.
  4208 
  4209 * Theory Nat: definition of <= and < on natural numbers no longer
  4210 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  4211 le_def and less_def have disappeared.  Consider lemmas not_less
  4212 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  4213 
  4214 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  4215 (whose purpose mainly is for various fold_set functionals) have been
  4216 abandoned in favor of the existing algebraic classes
  4217 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  4218 lower_semilattice (resp. upper_semilattice) and linorder.
  4219 INCOMPATIBILITY.
  4220 
  4221 * Theory Transitive_Closure: induct and cases rules now declare proper
  4222 case_names ("base" and "step").  INCOMPATIBILITY.
  4223 
  4224 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  4225 lattices.  The form set-specific version is available as
  4226 Inductive.lfp_ordinal_induct_set.
  4227 
  4228 * Renamed theorems "power.simps" to "power_int.simps".
  4229 INCOMPATIBILITY.
  4230 
  4231 * Class semiring_div provides basic abstract properties of semirings
  4232 with division and modulo operations.  Subsumes former class dvd_mod.
  4233 
  4234 * Merged theories IntDef, Numeral and IntArith into unified theory
  4235 Int.  INCOMPATIBILITY.
  4236 
  4237 * Theory Library/Code_Index: type "index" now represents natural
  4238 numbers rather than integers.  INCOMPATIBILITY.
  4239 
  4240 * New class "uminus" with operation "uminus" (split of from class
  4241 "minus" which now only has operation "minus", binary).
  4242 INCOMPATIBILITY.
  4243 
  4244 * Constants "card", "internal_split", "option_map" now with authentic
  4245 syntax.  INCOMPATIBILITY.
  4246 
  4247 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  4248 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  4249 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  4250 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  4251 Sup_set_def, le_def, less_def, option_map_def now with object
  4252 equality.  INCOMPATIBILITY.
  4253 
  4254 * Records. Removed K_record, and replaced it by pure lambda term
  4255 %x. c. The simplifier setup is now more robust against eta expansion.
  4256 INCOMPATIBILITY: in cases explicitly referring to K_record.
  4257 
  4258 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  4259 
  4260 * Library/ListVector: new theory of arithmetic vector operations.
  4261 
  4262 * Library/Order_Relation: new theory of various orderings as sets of
  4263 pairs.  Defines preorders, partial orders, linear orders and
  4264 well-orders on sets and on types.
  4265 
  4266 
  4267 *** ZF ***
  4268 
  4269 * Renamed some theories to allow to loading both ZF and HOL in the
  4270 same session:
  4271 
  4272   Datatype  -> Datatype_ZF
  4273   Inductive -> Inductive_ZF
  4274   Int       -> Int_ZF
  4275   IntDiv    -> IntDiv_ZF
  4276   Nat       -> Nat_ZF
  4277   List      -> List_ZF
  4278   Main      -> Main_ZF
  4279 
  4280 INCOMPATIBILITY: ZF theories that import individual theories below
  4281 Main might need to be adapted.  Regular theory Main is still
  4282 available, as trivial extension of Main_ZF.
  4283 
  4284 
  4285 *** ML ***
  4286 
  4287 * ML within Isar: antiquotation @{const name} or @{const
  4288 name(typargs)} produces statically-checked Const term.
  4289 
  4290 * Functor NamedThmsFun: data is available to the user as dynamic fact
  4291 (of the same name).  Removed obsolete print command.
  4292 
  4293 * Removed obsolete "use_legacy_bindings" function.
  4294 
  4295 * The ``print mode'' is now a thread-local value derived from a global
  4296 template (the former print_mode reference), thus access becomes
  4297 non-critical.  The global print_mode reference is for session
  4298 management only; user-code should use print_mode_value,
  4299 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  4300 
  4301 * Functions system/system_out provide a robust way to invoke external
  4302 shell commands, with propagation of interrupts (requires Poly/ML
  4303 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  4304 
  4305 
  4306 *** System ***
  4307 
  4308 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  4309 in accordance with Proof General 3.7, which prefers GNU emacs.
  4310 
  4311 * isatool tty runs Isabelle process with plain tty interaction;
  4312 optional line editor may be specified via ISABELLE_LINE_EDITOR
  4313 setting, the default settings attempt to locate "ledit" and "rlwrap".
  4314 
  4315 * isatool browser now works with Cygwin as well, using general
  4316 "javapath" function defined in Isabelle process environment.
  4317 
  4318 * YXML notation provides a simple and efficient alternative to
  4319 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  4320 isatool yxml as described in the Isabelle system manual.
  4321 
  4322 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  4323 provides general wrapper for managing an Isabelle process in a robust
  4324 fashion, with ``cooked'' output from stdin/stderr.
  4325 
  4326 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  4327 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  4328 
  4329 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  4330 way of changing the user's settings is via
  4331 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  4332 script.
  4333 
  4334 * Multithreading.max_threads := 0 refers to the number of actual CPU
  4335 cores of the underlying machine, which is a good starting point for
  4336 optimal performance tuning.  The corresponding usedir option -M allows
  4337 "max" as an alias for "0".  WARNING: does not work on certain versions
  4338 of Mac OS (with Poly/ML 5.1).
  4339 
  4340 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  4341 adverse effect of Isabelle flooding interactive front-ends (notably
  4342 ProofGeneral / XEmacs).
  4343 
  4344 
  4345 
  4346 New in Isabelle2007 (November 2007)
  4347 -----------------------------------
  4348 
  4349 *** General ***
  4350 
  4351 * More uniform information about legacy features, notably a
  4352 warning/error of "Legacy feature: ...", depending on the state of the
  4353 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  4354 legacy features will disappear eventually.
  4355 
  4356 * Theory syntax: the header format ``theory A = B + C:'' has been
  4357 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  4358 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  4359 
  4360 * Theory syntax: the old non-Isar theory file format has been
  4361 discontinued altogether.  Note that ML proof scripts may still be used
  4362 with Isar theories; migration is usually quite simple with the ML
  4363 function use_legacy_bindings.  INCOMPATIBILITY.
  4364 
  4365 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  4366 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  4367 quotes.
  4368 
  4369 * Theory loader: be more serious about observing the static theory
  4370 header specifications (including optional directories), but not the
  4371 accidental file locations of previously successful loads.  The strict
  4372 update policy of former update_thy is now already performed by
  4373 use_thy, so the former has been removed; use_thys updates several
  4374 theories simultaneously, just as 'imports' within a theory header
  4375 specification, but without merging the results.  Potential
  4376 INCOMPATIBILITY: may need to refine theory headers and commands
  4377 ROOT.ML which depend on load order.
  4378 
  4379 * Theory loader: optional support for content-based file
  4380 identification, instead of the traditional scheme of full physical
  4381 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  4382 (cf. the system manual).  The new scheme allows to work with
  4383 non-finished theories in persistent session images, such that source
  4384 files may be moved later on without requiring reloads.
  4385 
  4386 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4387 file (with the same base name as the theory) are considered a legacy
  4388 feature, which will disappear eventually. Even now, the theory loader
  4389 no longer maintains dependencies on such files.
  4390 
  4391 * Syntax: the scope for resolving ambiguities via type-inference is
  4392 now limited to individual terms, instead of whole simultaneous
  4393 specifications as before. This greatly reduces the complexity of the
  4394 syntax module and improves flexibility by separating parsing and
  4395 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  4396 'fixes' etc.) are required in rare situations.
  4397 
  4398 * Syntax: constants introduced by new-style packages ('definition',
  4399 'abbreviation' etc.) are passed through the syntax module in
  4400 ``authentic mode''. This means that associated mixfix annotations
  4401 really stick to such constants, independently of potential name space
  4402 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  4403 trees are represented slightly differently, may need to adapt syntax
  4404 translations accordingly. Use CONST marker in 'translations' and
  4405 @{const_syntax} antiquotation in 'parse_translation' etc.
  4406 
  4407 * Legacy goal package: reduced interface to the bare minimum required
  4408 to keep existing proof scripts running.  Most other user-level
  4409 functions are now part of the OldGoals structure, which is *not* open
  4410 by default (consider isatool expandshort before open OldGoals).
  4411 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  4412 these tend to cause confusion about the actual goal (!) context being
  4413 used here, which is not necessarily the same as the_context().
  4414 
  4415 * Command 'find_theorems': supports "*" wild-card in "name:"
  4416 criterion; "with_dups" option.  Certain ProofGeneral versions might
  4417 support a specific search form (see ProofGeneral/CHANGES).
  4418 
  4419 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  4420 by default, which means that "prems" (and also "fixed variables") are
  4421 suppressed from proof state output.  Note that the ProofGeneral
  4422 settings mechanism allows to change and save options persistently, but
  4423 older versions of Isabelle will fail to start up if a negative prems
  4424 limit is imposed.
  4425 
  4426 * Local theory targets may be specified by non-nested blocks of
  4427 ``context/locale/class ... begin'' followed by ``end''.  The body may
  4428 contain definitions, theorems etc., including any derived mechanism
  4429 that has been implemented on top of these primitives.  This concept
  4430 generalizes the existing ``theorem (in ...)'' towards more versatility
  4431 and scalability.
  4432 
  4433 * Proof General interface: proper undo of final 'end' command;
  4434 discontinued Isabelle/classic mode (ML proof scripts).
  4435 
  4436 
  4437 *** Document preparation ***
  4438 
  4439 * Added antiquotation @{theory name} which prints the given name,
  4440 after checking that it refers to a valid ancestor theory in the
  4441 current context.
  4442 
  4443 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  4444 check the given source text as ML type/structure, printing verbatim.
  4445 
  4446 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  4447 "c args == rhs" given in the current context.  (Any number of
  4448 arguments may be given on the LHS.)
  4449 
  4450 
  4451 *** Pure ***
  4452 
  4453 * The 'class' package offers a combination of axclass and locale to
  4454 achieve Haskell-like type classes in Isabelle.  Definitions and
  4455 theorems within a class context produce both relative results (with
  4456 implicit parameters according to the locale context), and polymorphic
  4457 constants with qualified polymorphism (according to the class
  4458 context).  Within the body context of a 'class' target, a separate
  4459 syntax layer ("user space type system") takes care of converting
  4460 between global polymorphic consts and internal locale representation.
  4461 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  4462 "isatool doc classes" provides a tutorial.
  4463 
  4464 * Generic code generator framework allows to generate executable
  4465 code for ML and Haskell (including Isabelle classes).  A short usage
  4466 sketch:
  4467 
  4468     internal compilation:
  4469         export_code <list of constants (term syntax)> in SML
  4470     writing SML code to a file:
  4471         export_code <list of constants (term syntax)> in SML <filename>
  4472     writing OCaml code to a file:
  4473         export_code <list of constants (term syntax)> in OCaml <filename>
  4474     writing Haskell code to a bunch of files:
  4475         export_code <list of constants (term syntax)> in Haskell <filename>
  4476 
  4477     evaluating closed propositions to True/False using code generation:
  4478         method ``eval''
  4479 
  4480 Reasonable default setup of framework in HOL.
  4481 
  4482 Theorem attributs for selecting and transforming function equations theorems:
  4483 
  4484     [code fun]:        select a theorem as function equation for a specific constant
  4485     [code fun del]:    deselect a theorem as function equation for a specific constant
  4486     [code inline]:     select an equation theorem for unfolding (inlining) in place
  4487     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  4488 
  4489 User-defined serializations (target in {SML, OCaml, Haskell}):
  4490 
  4491     code_const <and-list of constants (term syntax)>
  4492       {(target) <and-list of const target syntax>}+
  4493 
  4494     code_type <and-list of type constructors>
  4495       {(target) <and-list of type target syntax>}+
  4496 
  4497     code_instance <and-list of instances>
  4498       {(target)}+
  4499         where instance ::= <type constructor> :: <class>
  4500 
  4501     code_class <and_list of classes>
  4502       {(target) <and-list of class target syntax>}+
  4503         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4504 
  4505 code_instance and code_class only are effective to target Haskell.
  4506 
  4507 For example usage see src/HOL/ex/Codegenerator.thy and
  4508 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4509 generation from Isabelle/HOL theories is available via "isatool doc
  4510 codegen".
  4511 
  4512 * Code generator: consts in 'consts_code' Isar commands are now
  4513 referred to by usual term syntax (including optional type
  4514 annotations).
  4515 
  4516 * Command 'no_translations' removes translation rules from theory
  4517 syntax.
  4518 
  4519 * Overloaded definitions are now actually checked for acyclic
  4520 dependencies.  The overloading scheme is slightly more general than
  4521 that of Haskell98, although Isabelle does not demand an exact
  4522 correspondence to type class and instance declarations.
  4523 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4524 exotic versions of overloading -- at the discretion of the user!
  4525 
  4526 Polymorphic constants are represented via type arguments, i.e. the
  4527 instantiation that matches an instance against the most general
  4528 declaration given in the signature.  For example, with the declaration
  4529 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4530 as c(nat).  Overloading is essentially simultaneous structural
  4531 recursion over such type arguments.  Incomplete specification patterns
  4532 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4533 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4534 Command 'print_theory' outputs the normalized system of recursive
  4535 equations, see section "definitions".
  4536 
  4537 * Configuration options are maintained within the theory or proof
  4538 context (with name and type bool/int/string), providing a very simple
  4539 interface to a poor-man's version of general context data.  Tools may
  4540 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4541 these values using Config.get etc.  Users may change options via an
  4542 associated attribute of the same name.  This form of context
  4543 declaration works particularly well with commands 'declare' or
  4544 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4545 very easy to avoid global references, which would not observe Isar
  4546 toplevel undo/redo and fail to work with multithreading.
  4547 
  4548 Various global ML references of Pure and HOL have been turned into
  4549 configuration options:
  4550 
  4551   Unify.search_bound		unify_search_bound
  4552   Unify.trace_bound		unify_trace_bound
  4553   Unify.trace_simp		unify_trace_simp
  4554   Unify.trace_types		unify_trace_types
  4555   Simplifier.simp_depth_limit	simp_depth_limit
  4556   Blast.depth_limit		blast_depth_limit
  4557   DatatypeProp.dtK		datatype_distinctness_limit
  4558   fast_arith_neq_limit  	fast_arith_neq_limit
  4559   fast_arith_split_limit	fast_arith_split_limit
  4560 
  4561 * Named collections of theorems may be easily installed as context
  4562 data using the functor NamedThmsFun (see also
  4563 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4564 attributes; there is also a toplevel print command.  This facility is
  4565 just a common case of general context data, which is the preferred way
  4566 for anything more complex than just a list of facts in canonical
  4567 order.
  4568 
  4569 * Isar: command 'declaration' augments a local theory by generic
  4570 declaration functions written in ML.  This enables arbitrary content
  4571 being added to the context, depending on a morphism that tells the
  4572 difference of the original declaration context wrt. the application
  4573 context encountered later on.
  4574 
  4575 * Isar: proper interfaces for simplification procedures.  Command
  4576 'simproc_setup' declares named simprocs (with match patterns, and body
  4577 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4578 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4579 
  4580 * Isar: an extra pair of brackets around attribute declarations
  4581 abbreviates a theorem reference involving an internal dummy fact,
  4582 which will be ignored later --- only the effect of the attribute on
  4583 the background context will persist.  This form of in-place
  4584 declarations is particularly useful with commands like 'declare' and
  4585 'using', for example ``have A using [[simproc a]] by simp''.
  4586 
  4587 * Isar: method "assumption" (and implicit closing of subproofs) now
  4588 takes simple non-atomic goal assumptions into account: after applying
  4589 an assumption as a rule the resulting subgoals are solved by atomic
  4590 assumption steps.  This is particularly useful to finish 'obtain'
  4591 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4592 without referring to the original premise "!!x. P x ==> thesis" in the
  4593 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4594 more permissive.
  4595 
  4596 * Isar: implicit use of prems from the Isar proof context is
  4597 considered a legacy feature.  Common applications like ``have A .''
  4598 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4599 referencing facts explicitly here improves readability and
  4600 maintainability of proof texts.
  4601 
  4602 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4603 the obtained context from the course of reasoning!  For example:
  4604 
  4605   assume "EX x y. A x & B y"   -- "any previous fact"
  4606   then guess x and y by clarify
  4607 
  4608 This technique is potentially adventurous, depending on the facts and
  4609 proof tools being involved here.
  4610 
  4611 * Isar: known facts from the proof context may be specified as literal
  4612 propositions, using ASCII back-quote syntax.  This works wherever
  4613 named facts used to be allowed so far, in proof commands, proof
  4614 methods, attributes etc.  Literal facts are retrieved from the context
  4615 according to unification of type and term parameters.  For example,
  4616 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4617 theorems in the current context, then these are valid literal facts:
  4618 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4619 
  4620 There is also a proof method "fact" which does the same composition
  4621 for explicit goal states, e.g. the following proof texts coincide with
  4622 certain special cases of literal facts:
  4623 
  4624   have "A" by fact                 ==  note `A`
  4625   have "A ==> B" by fact           ==  note `A ==> B`
  4626   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4627   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4628 
  4629 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4630 outer syntax.  Thus symbolic identifiers may be used without
  4631 additional white space in declarations like this: ``assume *: A''.
  4632 
  4633 * Isar: 'print_facts' prints all local facts of the current context,
  4634 both named and unnamed ones.
  4635 
  4636 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4637 
  4638   def x == "t" and y == "u"
  4639 
  4640 * Isar: added command 'unfolding', which is structurally similar to
  4641 'using', but affects both the goal state and facts by unfolding given
  4642 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4643 'unfolded' attribute may be replaced by first-class proof text.
  4644 
  4645 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4646 and command 'unfolding' now all support object-level equalities
  4647 (potentially conditional).  The underlying notion of rewrite rule is
  4648 analogous to the 'rule_format' attribute, but *not* that of the
  4649 Simplifier (which is usually more generous).
  4650 
  4651 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4652 premises of a theorem by n. Useful in conjunction with drule.
  4653 
  4654 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4655 method expression within a sandbox consisting of the first N
  4656 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4657 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4658 simplifies all new goals that emerge from applying rule foo to the
  4659 originally first one.
  4660 
  4661 * Isar: schematic goals are no longer restricted to higher-order
  4662 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4663 expected.
  4664 
  4665 * Isar: the conclusion of a long theorem statement is now either
  4666 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4667 (essentially a disjunction of cases with local parameters and
  4668 assumptions).  The latter allows to express general elimination rules
  4669 adequately; in this notation common elimination rules look like this:
  4670 
  4671   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4672     assumes "EX x. P x"
  4673     obtains x where "P x"
  4674 
  4675   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4676     assumes "A & B"
  4677     obtains A and B
  4678 
  4679   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4680     assumes "A | B"
  4681     obtains
  4682       A
  4683     | B
  4684 
  4685 The subsequent classical rules even refer to the formal "thesis"
  4686 explicitly:
  4687 
  4688   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4689     obtains "~ thesis"
  4690 
  4691   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4692     obtains "thesis ==> something"
  4693 
  4694 The actual proof of an 'obtains' statement is analogous to that of the
  4695 Isar proof element 'obtain', only that there may be several cases.
  4696 Optional case names may be specified in parentheses; these will be
  4697 available both in the present proof and as annotations in the
  4698 resulting rule, for later use with the 'cases' method (cf. attribute
  4699 case_names).
  4700 
  4701 * Isar: the assumptions of a long theorem statement are available as
  4702 "assms" fact in the proof context.  This is more appropriate than the
  4703 (historical) "prems", which refers to all assumptions of the current
  4704 context, including those from the target locale, proof body etc.
  4705 
  4706 * Isar: 'print_statement' prints theorems from the current theory or
  4707 proof context in long statement form, according to the syntax of a
  4708 top-level lemma.
  4709 
  4710 * Isar: 'obtain' takes an optional case name for the local context
  4711 introduction rule (default "that").
  4712 
  4713 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4714 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4715 to occur.
  4716 
  4717 * Pure: syntax "CONST name" produces a fully internalized constant
  4718 according to the current context.  This is particularly useful for
  4719 syntax translations that should refer to internal constant
  4720 representations independently of name spaces.
  4721 
  4722 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4723 instead of "FOO ". This allows multiple binder declarations to coexist
  4724 in the same context.  INCOMPATIBILITY.
  4725 
  4726 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4727 primitive that also works in a locale context (both for constants and
  4728 fixed variables). Type declaration and internal syntactic representation
  4729 of given constants retrieved from the context. Likewise, the
  4730 'no_notation' command allows to remove given syntax annotations from the
  4731 current context.
  4732 
  4733 * Isar/locales: new derived specification elements 'axiomatization',
  4734 'definition', 'abbreviation', which support type-inference, admit
  4735 object-level specifications (equality, equivalence).  See also the
  4736 isar-ref manual.  Examples:
  4737 
  4738   axiomatization
  4739     eq  (infix "===" 50) where
  4740     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4741 
  4742   definition "f x y = x + y + 1"
  4743   definition g where "g x = f x x"
  4744 
  4745   abbreviation
  4746     neq  (infix "=!=" 50) where
  4747     "x =!= y == ~ (x === y)"
  4748 
  4749 These specifications may be also used in a locale context.  Then the
  4750 constants being introduced depend on certain fixed parameters, and the
  4751 constant name is qualified by the locale base name.  An internal
  4752 abbreviation takes care for convenient input and output, making the
  4753 parameters implicit and using the original short name.  See also
  4754 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4755 entities from a monomorphic theory.
  4756 
  4757 Presently, abbreviations are only available 'in' a target locale, but
  4758 not inherited by general import expressions.  Also note that
  4759 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4760 'translations' in common applications.  The "no_abbrevs" print mode
  4761 prevents folding of abbreviations in term output.
  4762 
  4763 Concrete syntax is attached to specified constants in internal form,
  4764 independently of name spaces.  The parse tree representation is
  4765 slightly different -- use 'notation' instead of raw 'syntax', and
  4766 'translations' with explicit "CONST" markup to accommodate this.
  4767 
  4768 * Pure/Isar: unified syntax for new-style specification mechanisms
  4769 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4770 full type inference and dummy patterns ("_").  For example:
  4771 
  4772   definition "K x _ = x"
  4773 
  4774   inductive conj for A B
  4775   where "A ==> B ==> conj A B"
  4776 
  4777 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4778 the current context.  Print mode "no_abbrevs" prevents inversion of
  4779 abbreviations on output.
  4780 
  4781 * Isar/locales: improved parameter handling: use of locales "var" and
  4782 "struct" no longer necessary; - parameter renamings are no longer
  4783 required to be injective.  For example, this allows to define
  4784 endomorphisms as locale endom = homom mult mult h.
  4785 
  4786 * Isar/locales: changed the way locales with predicates are defined.
  4787 Instead of accumulating the specification, the imported expression is
  4788 now an interpretation.  INCOMPATIBILITY: different normal form of
  4789 locale expressions.  In particular, in interpretations of locales with
  4790 predicates, goals repesenting already interpreted fragments are not
  4791 removed automatically.  Use methods `intro_locales' and
  4792 `unfold_locales'; see below.
  4793 
  4794 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4795 provide backward reasoning on locales predicates.  The methods are
  4796 aware of interpretations and discharge corresponding goals.
  4797 `intro_locales' is less aggressive then `unfold_locales' and does not
  4798 unfold predicates to assumptions.
  4799 
  4800 * Isar/locales: the order in which locale fragments are accumulated
  4801 has changed.  This enables to override declarations from fragments due
  4802 to interpretations -- for example, unwanted simp rules.
  4803 
  4804 * Isar/locales: interpretation in theories and proof contexts has been
  4805 extended.  One may now specify (and prove) equations, which are
  4806 unfolded in interpreted theorems.  This is useful for replacing
  4807 defined concepts (constants depending on locale parameters) by
  4808 concepts already existing in the target context.  Example:
  4809 
  4810   interpretation partial_order ["op <= :: [int, int] => bool"]
  4811     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4812 
  4813 Typically, the constant `partial_order.less' is created by a
  4814 definition specification element in the context of locale
  4815 partial_order.
  4816 
  4817 * Method "induct": improved internal context management to support
  4818 local fixes and defines on-the-fly. Thus explicit meta-level
  4819 connectives !!  and ==> are rarely required anymore in inductive goals
  4820 (using object-logic connectives for this purpose has been long
  4821 obsolete anyway). Common proof patterns are explained in
  4822 src/HOL/Induct/Common_Patterns.thy, see also
  4823 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4824 examples.
  4825 
  4826 * Method "induct": improved handling of simultaneous goals. Instead of
  4827 introducing object-level conjunction, the statement is now split into
  4828 several conclusions, while the corresponding symbolic cases are nested
  4829 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4830 see src/HOL/Induct/Common_Patterns.thy, for example.
  4831 
  4832 * Method "induct": mutual induction rules are now specified as a list
  4833 of rule sharing the same induction cases. HOL packages usually provide
  4834 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4835 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4836 mutual induction rules differently, i.e. like this:
  4837 
  4838   (induct rule: foo_bar.inducts)
  4839   (induct set: foo bar)
  4840   (induct pred: foo bar)
  4841   (induct type: foo bar)
  4842 
  4843 The ML function ProjectRule.projections turns old-style rules into the
  4844 new format.
  4845 
  4846 * Method "coinduct": dual of induction, see
  4847 src/HOL/Library/Coinductive_List.thy for various examples.
  4848 
  4849 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4850 considered a legacy feature.
  4851 
  4852 * Attribute "symmetric" produces result with standardized schematic
  4853 variables (index 0).  Potential INCOMPATIBILITY.
  4854 
  4855 * Simplifier: by default the simplifier trace only shows top level
  4856 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4857 default. Thus there is less danger of being flooded by the trace. The
  4858 trace indicates where parts have been suppressed.
  4859   
  4860 * Provers/classical: removed obsolete classical version of elim_format
  4861 attribute; classical elim/dest rules are now treated uniformly when
  4862 manipulating the claset.
  4863 
  4864 * Provers/classical: stricter checks to ensure that supplied intro,
  4865 dest and elim rules are well-formed; dest and elim rules must have at
  4866 least one premise.
  4867 
  4868 * Provers/classical: attributes dest/elim/intro take an optional
  4869 weight argument for the rule (just as the Pure versions).  Weights are
  4870 ignored by automated tools, but determine the search order of single
  4871 rule steps.
  4872 
  4873 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4874 where the body does not mention the bound variable.  Note that dummy
  4875 patterns implicitly depend on their context of bounds, which makes
  4876 "{_. _}" match any set comprehension as expected.  Potential
  4877 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4878 constant "_idtdummy" in the binding position.
  4879 
  4880 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4881 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4882 for example "A -> B" => "Pi A (%_. B)".
  4883 
  4884 * Pure: 'class_deps' command visualizes the subclass relation, using
  4885 the graph browser tool.
  4886 
  4887 * Pure: 'print_theory' now suppresses certain internal declarations by
  4888 default; use '!' option for full details.
  4889 
  4890 
  4891 *** HOL ***
  4892 
  4893 * Method "metis" proves goals by applying the Metis general-purpose
  4894 resolution prover (see also http://gilith.com/software/metis/).
  4895 Examples are in the directory MetisExamples.  WARNING: the
  4896 Isabelle/HOL-Metis integration does not yet work properly with
  4897 multi-threading.
  4898   
  4899 * Command 'sledgehammer' invokes external automatic theorem provers as
  4900 background processes.  It generates calls to the "metis" method if
  4901 successful. These can be pasted into the proof.  Users do not have to
  4902 wait for the automatic provers to return.  WARNING: does not really
  4903 work with multi-threading.
  4904 
  4905 * New "auto_quickcheck" feature tests outermost goal statements for
  4906 potential counter-examples.  Controlled by ML references
  4907 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4908 5000 milliseconds).  Fails silently if statements is outside of
  4909 executable fragment, or any other codgenerator problem occurs.
  4910 
  4911 * New constant "undefined" with axiom "undefined x = undefined".
  4912 
  4913 * Added class "HOL.eq", allowing for code generation with polymorphic
  4914 equality.
  4915 
  4916 * Some renaming of class constants due to canonical name prefixing in
  4917 the new 'class' package:
  4918 
  4919     HOL.abs ~> HOL.abs_class.abs
  4920     HOL.divide ~> HOL.divide_class.divide
  4921     0 ~> HOL.zero_class.zero
  4922     1 ~> HOL.one_class.one
  4923     op + ~> HOL.plus_class.plus
  4924     op - ~> HOL.minus_class.minus
  4925     uminus ~> HOL.minus_class.uminus
  4926     op * ~> HOL.times_class.times
  4927     op < ~> HOL.ord_class.less
  4928     op <= > HOL.ord_class.less_eq
  4929     Nat.power ~> Power.power_class.power
  4930     Nat.size ~> Nat.size_class.size
  4931     Numeral.number_of ~> Numeral.number_class.number_of
  4932     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4933     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4934     Orderings.min ~> Orderings.ord_class.min
  4935     Orderings.max ~> Orderings.ord_class.max
  4936     Divides.op div ~> Divides.div_class.div
  4937     Divides.op mod ~> Divides.div_class.mod
  4938     Divides.op dvd ~> Divides.div_class.dvd
  4939 
  4940 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4941 
  4942 a) User-defined constants using any of the names "plus", "minus",
  4943 "times", "less" or "less_eq". The standard syntax translations for
  4944 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4945 names.
  4946 
  4947 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4948 INCOMPATIBILITY: use more specific names.
  4949 
  4950 c) Permutative equations (e.g. "a + b = b + a")
  4951 Since the change of names also changes the order of terms, permutative
  4952 rewrite rules may get applied in a different order. Experience shows
  4953 that this is rarely the case (only two adaptions in the whole Isabelle
  4954 distribution).  INCOMPATIBILITY: rewrite proofs
  4955 
  4956 d) ML code directly refering to constant names
  4957 This in general only affects hand-written proof tactics, simprocs and
  4958 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4959 Consider using @{const_name} antiquotation.
  4960 
  4961 * New class "default" with associated constant "default".
  4962 
  4963 * Function "sgn" is now overloaded and available on int, real, complex
  4964 (and other numeric types), using class "sgn".  Two possible defs of
  4965 sgn are given as equational assumptions in the classes sgn_if and
  4966 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4967 INCOMPATIBILITY.
  4968 
  4969 * Locale "partial_order" now unified with class "order" (cf. theory
  4970 Orderings), added parameter "less".  INCOMPATIBILITY.
  4971 
  4972 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4973 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4974 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4975 
  4976 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4977 changed order of proof goals in instance proofs.
  4978 
  4979 * The transitivity reasoner for partial and linear orders is set up
  4980 for classes "order" and "linorder".  Instances of the reasoner are available
  4981 in all contexts importing or interpreting the corresponding locales.
  4982 Method "order" invokes the reasoner separately; the reasoner
  4983 is also integrated with the Simplifier as a solver.  Diagnostic
  4984 command 'print_orders' shows the available instances of the reasoner
  4985 in the current context.
  4986 
  4987 * Localized monotonicity predicate in theory "Orderings"; integrated
  4988 lemmas max_of_mono and min_of_mono with this predicate.
  4989 INCOMPATIBILITY.
  4990 
  4991 * Formulation of theorem "dense" changed slightly due to integration
  4992 with new class dense_linear_order.
  4993 
  4994 * Uniform lattice theory development in HOL.
  4995 
  4996     constants "meet" and "join" now named "inf" and "sup"
  4997     constant "Meet" now named "Inf"
  4998 
  4999     classes "meet_semilorder" and "join_semilorder" now named
  5000       "lower_semilattice" and "upper_semilattice"
  5001     class "lorder" now named "lattice"
  5002     class "comp_lat" now named "complete_lattice"
  5003 
  5004     Instantiation of lattice classes allows explicit definitions
  5005     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  5006 
  5007   INCOMPATIBILITY.  Theorem renames:
  5008 
  5009     meet_left_le            ~> inf_le1
  5010     meet_right_le           ~> inf_le2
  5011     join_left_le            ~> sup_ge1
  5012     join_right_le           ~> sup_ge2
  5013     meet_join_le            ~> inf_sup_ord
  5014     le_meetI                ~> le_infI
  5015     join_leI                ~> le_supI
  5016     le_meet                 ~> le_inf_iff
  5017     le_join                 ~> ge_sup_conv
  5018     meet_idempotent         ~> inf_idem
  5019     join_idempotent         ~> sup_idem
  5020     meet_comm               ~> inf_commute
  5021     join_comm               ~> sup_commute
  5022     meet_leI1               ~> le_infI1
  5023     meet_leI2               ~> le_infI2
  5024     le_joinI1               ~> le_supI1
  5025     le_joinI2               ~> le_supI2
  5026     meet_assoc              ~> inf_assoc
  5027     join_assoc              ~> sup_assoc
  5028     meet_left_comm          ~> inf_left_commute
  5029     meet_left_idempotent    ~> inf_left_idem
  5030     join_left_comm          ~> sup_left_commute
  5031     join_left_idempotent    ~> sup_left_idem
  5032     meet_aci                ~> inf_aci
  5033     join_aci                ~> sup_aci
  5034     le_def_meet             ~> le_iff_inf
  5035     le_def_join             ~> le_iff_sup
  5036     join_absorp2            ~> sup_absorb2
  5037     join_absorp1            ~> sup_absorb1
  5038     meet_absorp1            ~> inf_absorb1
  5039     meet_absorp2            ~> inf_absorb2
  5040     meet_join_absorp        ~> inf_sup_absorb
  5041     join_meet_absorp        ~> sup_inf_absorb
  5042     distrib_join_le         ~> distrib_sup_le
  5043     distrib_meet_le         ~> distrib_inf_le
  5044 
  5045     add_meet_distrib_left   ~> add_inf_distrib_left
  5046     add_join_distrib_left   ~> add_sup_distrib_left
  5047     is_join_neg_meet        ~> is_join_neg_inf
  5048     is_meet_neg_join        ~> is_meet_neg_sup
  5049     add_meet_distrib_right  ~> add_inf_distrib_right
  5050     add_join_distrib_right  ~> add_sup_distrib_right
  5051     add_meet_join_distribs  ~> add_sup_inf_distribs
  5052     join_eq_neg_meet        ~> sup_eq_neg_inf
  5053     meet_eq_neg_join        ~> inf_eq_neg_sup
  5054     add_eq_meet_join        ~> add_eq_inf_sup
  5055     meet_0_imp_0            ~> inf_0_imp_0
  5056     join_0_imp_0            ~> sup_0_imp_0
  5057     meet_0_eq_0             ~> inf_0_eq_0
  5058     join_0_eq_0             ~> sup_0_eq_0
  5059     neg_meet_eq_join        ~> neg_inf_eq_sup
  5060     neg_join_eq_meet        ~> neg_sup_eq_inf
  5061     join_eq_if              ~> sup_eq_if
  5062 
  5063     mono_meet               ~> mono_inf
  5064     mono_join               ~> mono_sup
  5065     meet_bool_eq            ~> inf_bool_eq
  5066     join_bool_eq            ~> sup_bool_eq
  5067     meet_fun_eq             ~> inf_fun_eq
  5068     join_fun_eq             ~> sup_fun_eq
  5069     meet_set_eq             ~> inf_set_eq
  5070     join_set_eq             ~> sup_set_eq
  5071     meet1_iff               ~> inf1_iff
  5072     meet2_iff               ~> inf2_iff
  5073     meet1I                  ~> inf1I
  5074     meet2I                  ~> inf2I
  5075     meet1D1                 ~> inf1D1
  5076     meet2D1                 ~> inf2D1
  5077     meet1D2                 ~> inf1D2
  5078     meet2D2                 ~> inf2D2
  5079     meet1E                  ~> inf1E
  5080     meet2E                  ~> inf2E
  5081     join1_iff               ~> sup1_iff
  5082     join2_iff               ~> sup2_iff
  5083     join1I1                 ~> sup1I1
  5084     join2I1                 ~> sup2I1
  5085     join1I1                 ~> sup1I1
  5086     join2I2                 ~> sup1I2
  5087     join1CI                 ~> sup1CI
  5088     join2CI                 ~> sup2CI
  5089     join1E                  ~> sup1E
  5090     join2E                  ~> sup2E
  5091 
  5092     is_meet_Meet            ~> is_meet_Inf
  5093     Meet_bool_def           ~> Inf_bool_def
  5094     Meet_fun_def            ~> Inf_fun_def
  5095     Meet_greatest           ~> Inf_greatest
  5096     Meet_lower              ~> Inf_lower
  5097     Meet_set_def            ~> Inf_set_def
  5098 
  5099     Sup_def                 ~> Sup_Inf
  5100     Sup_bool_eq             ~> Sup_bool_def
  5101     Sup_fun_eq              ~> Sup_fun_def
  5102     Sup_set_eq              ~> Sup_set_def
  5103 
  5104     listsp_meetI            ~> listsp_infI
  5105     listsp_meet_eq          ~> listsp_inf_eq
  5106 
  5107     meet_min                ~> inf_min
  5108     join_max                ~> sup_max
  5109 
  5110 * Added syntactic class "size"; overloaded constant "size" now has
  5111 type "'a::size ==> bool"
  5112 
  5113 * Internal reorganisation of `size' of datatypes: size theorems
  5114 "foo.size" are no longer subsumed by "foo.simps" (but are still
  5115 simplification rules by default!); theorems "prod.size" now named
  5116 "*.size".
  5117 
  5118 * Class "div" now inherits from class "times" rather than "type".
  5119 INCOMPATIBILITY.
  5120 
  5121 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  5122 Linorder etc.  have disappeared; operations defined in terms of
  5123 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  5124 
  5125 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  5126 
  5127 * HOL-Word: New extensive library and type for generic, fixed size
  5128 machine words, with arithemtic, bit-wise, shifting and rotating
  5129 operations, reflection into int, nat, and bool lists, automation for
  5130 linear arithmetic (by automatic reflection into nat or int), including
  5131 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  5132 arithmetic type classes, supporting automatic simplification of
  5133 numerals on all operations.
  5134 
  5135 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  5136 
  5137 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  5138 
  5139 * Code generator library theories:
  5140   - Code_Integer represents HOL integers by big integer literals in target
  5141     languages.
  5142   - Code_Char represents HOL characters by character literals in target
  5143     languages.
  5144   - Code_Char_chr like Code_Char, but also offers treatment of character
  5145     codes; includes Code_Integer.
  5146   - Executable_Set allows to generate code for finite sets using lists.
  5147   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  5148     denominator).
  5149   - Executable_Real implements a subset of real numbers, namly those
  5150     representable by rational numbers.
  5151   - Efficient_Nat implements natural numbers by integers, which in general will
  5152     result in higher efficency; pattern matching with 0/Suc is eliminated;
  5153     includes Code_Integer.
  5154   - Code_Index provides an additional datatype index which is mapped to
  5155     target-language built-in integers.
  5156   - Code_Message provides an additional datatype message_string which is isomorphic to
  5157     strings; messages are mapped to target-language strings.
  5158 
  5159 * New package for inductive predicates
  5160 
  5161   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  5162 
  5163     inductive
  5164       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5165       for z_1 :: U_1 and ... and z_n :: U_m
  5166     where
  5167       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5168     | ...
  5169 
  5170   with full support for type-inference, rather than
  5171 
  5172     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5173 
  5174     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5175     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5176 
  5177     inductive "s z_1 ... z_m"
  5178     intros
  5179       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5180       ...
  5181 
  5182   For backward compatibility, there is a wrapper allowing inductive
  5183   sets to be defined with the new package via
  5184 
  5185     inductive_set
  5186       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5187       for z_1 :: U_1 and ... and z_n :: U_m
  5188     where
  5189       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5190     | ...
  5191 
  5192   or
  5193 
  5194     inductive_set
  5195       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5196       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5197       for z_1 :: U_1 and ... and z_n :: U_m
  5198     where
  5199       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5200     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5201     | ...
  5202 
  5203   if the additional syntax "p ..." is required.
  5204 
  5205   Numerous examples can be found in the subdirectories src/HOL/Auth,
  5206   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  5207 
  5208   INCOMPATIBILITIES:
  5209 
  5210   - Since declaration and definition of inductive sets or predicates
  5211     is no longer separated, abbreviations involving the newly
  5212     introduced sets or predicates must be specified together with the
  5213     introduction rules after the 'where' keyword (see above), rather
  5214     than before the actual inductive definition.
  5215 
  5216   - The variables in induction and elimination rules are now
  5217     quantified in the order of their occurrence in the introduction
  5218     rules, rather than in alphabetical order. Since this may break
  5219     some proofs, these proofs either have to be repaired, e.g. by
  5220     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  5221     statements of the form
  5222 
  5223       case (rule_i a_i_1 ... a_i_{k_i})
  5224 
  5225     or the old order of quantification has to be restored by explicitly adding
  5226     meta-level quantifiers in the introduction rules, i.e.
  5227 
  5228       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  5229 
  5230   - The format of the elimination rules is now
  5231 
  5232       p z_1 ... z_m x_1 ... x_n ==>
  5233         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5234         ==> ... ==> P
  5235 
  5236     for predicates and
  5237 
  5238       (x_1, ..., x_n) : s z_1 ... z_m ==>
  5239         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5240         ==> ... ==> P
  5241 
  5242     for sets rather than
  5243 
  5244       x : s z_1 ... z_m ==>
  5245         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  5246         ==> ... ==> P
  5247 
  5248     This may require terms in goals to be expanded to n-tuples
  5249     (e.g. using case_tac or simplification with the split_paired_all
  5250     rule) before the above elimination rule is applicable.
  5251 
  5252   - The elimination or case analysis rules for (mutually) inductive
  5253     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  5254     list of rules "p_1_..._p_k.elims" is no longer available.
  5255 
  5256 * New package "function"/"fun" for general recursive functions,
  5257 supporting mutual and nested recursion, definitions in local contexts,
  5258 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  5259 for small examples, and the separate tutorial on the function
  5260 package. The old recdef "package" is still available as before, but
  5261 users are encouraged to use the new package.
  5262 
  5263 * Method "lexicographic_order" automatically synthesizes termination
  5264 relations as lexicographic combinations of size measures. 
  5265 
  5266 * Case-expressions allow arbitrary constructor-patterns (including
  5267 "_") and take their order into account, like in functional
  5268 programming.  Internally, this is translated into nested
  5269 case-expressions; missing cases are added and mapped to the predefined
  5270 constant "undefined". In complicated cases printing may no longer show
  5271 the original input but the internal form. Lambda-abstractions allow
  5272 the same form of pattern matching: "% pat1 => e1 | ..." is an
  5273 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  5274 variable.
  5275 
  5276 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  5277 is an abbreviation for "of_nat :: nat => int". The simplification
  5278 rules for "of_nat" have been changed to work like "int" did
  5279 previously.  Potential INCOMPATIBILITY:
  5280   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  5281   - of_nat_diff and of_nat_mult are no longer default simp rules
  5282 
  5283 * Method "algebra" solves polynomial equations over (semi)rings using
  5284 Groebner bases. The (semi)ring structure is defined by locales and the
  5285 tool setup depends on that generic context. Installing the method for
  5286 a specific type involves instantiating the locale and possibly adding
  5287 declarations for computation on the coefficients.  The method is
  5288 already instantiated for natural numbers and for the axiomatic class
  5289 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  5290 CALCULEMUS 2007 for the general principles underlying this
  5291 architecture of context-aware proof-tools.
  5292 
  5293 * Method "ferrack" implements quantifier elimination over
  5294 special-purpose dense linear orders using locales (analogous to
  5295 "algebra"). The method is already installed for class
  5296 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  5297 rat, etc.
  5298 
  5299 * Former constant "List.op @" now named "List.append".  Use ML
  5300 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  5301 circumvent possible incompatibilities when working on ML level.
  5302 
  5303 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  5304 
  5305 * New function listsum :: 'a list => 'a for arbitrary monoids.
  5306 Special syntax: "SUM x <- xs. f x" (and latex variants)
  5307 
  5308 * New syntax for Haskell-like list comprehension (input only), eg.
  5309 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  5310 
  5311 * The special syntax for function "filter" has changed from [x :
  5312 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  5313 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  5314 
  5315 * [a..b] is now defined for arbitrary linear orders.  It used to be
  5316 defined on nat only, as an abbreviation for [a..<Suc b]
  5317 INCOMPATIBILITY.
  5318 
  5319 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  5320 
  5321 * New functions "sorted" and "sort" in src/HOL/List.thy.
  5322 
  5323 * New lemma collection field_simps (an extension of ring_simps) for
  5324 manipulating (in)equations involving division. Multiplies with all
  5325 denominators that can be proved to be non-zero (in equations) or
  5326 positive/negative (in inequations).
  5327 
  5328 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  5329 have been improved and renamed to ring_simps, group_simps and
  5330 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  5331 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  5332 
  5333 * Theory Library/Commutative_Ring: switched from recdef to function
  5334 package; constants add, mul, pow now curried.  Infix syntax for
  5335 algebraic operations.
  5336 
  5337 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  5338 INCOMPATIBILITY.
  5339 
  5340 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  5341 INCOMPATIBILITY.
  5342 
  5343 * HOL/records: generalised field-update to take a function on the
  5344 field rather than the new value: r(|A := x|) is translated to A_update
  5345 (K x) r The K-combinator that is internally used is called K_record.
  5346 INCOMPATIBILITY: Usage of the plain update functions has to be
  5347 adapted.
  5348  
  5349 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  5350 * x = 0, which are required for a semiring.  Richer structures do not
  5351 inherit from semiring_0 anymore, because this property is a theorem
  5352 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  5353 there is more to prove, but this is mostly trivial.
  5354 
  5355 * Class "recpower" is generalized to arbitrary monoids, not just
  5356 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  5357 commutativity or semiring properties additionally.
  5358 
  5359 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  5360 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  5361 better use 'abbreviation'.
  5362 
  5363 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  5364 
  5365 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  5366 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  5367 significant changes for setting up numeral syntax for types:
  5368   - New constants Numeral.pred and Numeral.succ instead
  5369       of former Numeral.bin_pred and Numeral.bin_succ.
  5370   - Use integer operations instead of bin_add, bin_mult and so on.
  5371   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  5372   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  5373 
  5374 See src/HOL/Integ/IntArith.thy for an example setup.
  5375 
  5376 * Command 'normal_form' computes the normal form of a term that may
  5377 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  5378 produces ``[b, c, a]'' (without proof).  This command is suitable for
  5379 heavy-duty computations because the functions are compiled to ML
  5380 first.  Correspondingly, a method "normalization" is provided.  See
  5381 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  5382 
  5383 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  5384 25 like -->); output depends on the "iff" print_mode, the default is
  5385 "A = B" (with priority 50).
  5386 
  5387 * Relations less (<) and less_eq (<=) are also available on type bool.
  5388 Modified syntax to disallow nesting without explicit parentheses,
  5389 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  5390 INCOMPATIBILITY.
  5391 
  5392 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  5393 
  5394 * Relation composition operator "op O" now has precedence 75 and binds
  5395 stronger than union and intersection. INCOMPATIBILITY.
  5396 
  5397 * The old set interval syntax "{m..n(}" (and relatives) has been
  5398 removed.  Use "{m..<n}" (and relatives) instead.
  5399 
  5400 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  5401 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  5402 ``declare [[simproc del: neq]]''.
  5403 
  5404 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  5405 True/False.
  5406 
  5407 * Theorem Cons_eq_map_conv no longer declared as "simp".
  5408 
  5409 * Theorem setsum_mult renamed to setsum_right_distrib.
  5410 
  5411 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  5412 ``rule'' method.
  5413 
  5414 * Reimplemented methods "sat" and "satx", with several improvements:
  5415 goals no longer need to be stated as "<prems> ==> False", equivalences
  5416 (i.e. "=" on type bool) are handled, variable names of the form
  5417 "lit_<n>" are no longer reserved, significant speedup.
  5418 
  5419 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  5420 zChaff is still supported as well.
  5421 
  5422 * 'inductive' and 'datatype': provide projections of mutual rules,
  5423 bundled as foo_bar.inducts;
  5424 
  5425 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  5426 Library.
  5427 
  5428 * Library: moved theory Accessible_Part to main HOL.
  5429 
  5430 * Library: added theory Coinductive_List of potentially infinite lists
  5431 as greatest fixed-point.
  5432 
  5433 * Library: added theory AssocList which implements (finite) maps as
  5434 association lists.
  5435 
  5436 * Method "evaluation" solves goals (i.e. a boolean expression)
  5437 efficiently by compiling it to ML.  The goal is "proved" (via an
  5438 oracle) if it evaluates to True.
  5439 
  5440 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  5441 also when invoked by the simplifier.  This results in the Simplifier
  5442 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  5443 Configuration option fast_arith_split_limit=0 recovers the old
  5444 behavior.
  5445 
  5446 * Support for hex (0x20) and binary (0b1001) numerals.
  5447 
  5448 * New method: reify eqs (t), where eqs are equations for an
  5449 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  5450 parameter, computes a term s::'b and a list xs::'a list and proves the
  5451 theorem I xs s = t. This is also known as reification or quoting. The
  5452 resulting theorem is applied to the subgoal to substitute t with I xs
  5453 s.  If t is omitted, the subgoal itself is reified.
  5454 
  5455 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  5456 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  5457 where f is supposed to be a computable function (in the sense of code
  5458 generattion). The method uses reify to compute s and xs as above then
  5459 applies corr_thm and uses normalization by evaluation to "prove" f s =
  5460 r and finally gets the theorem t = r, which is again applied to the
  5461 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  5462 
  5463 * Reflection: Automatic reification now handels binding, an example is
  5464 available in src/HOL/ex/ReflectionEx.thy
  5465 
  5466 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  5467 command 'statespace' that is similar to 'record', but introduces an
  5468 abstract specification based on the locale infrastructure instead of
  5469 HOL types.  This leads to extra flexibility in composing state spaces,
  5470 in particular multiple inheritance and renaming of components.
  5471 
  5472 
  5473 *** HOL-Complex ***
  5474 
  5475 * Hyperreal: Functions root and sqrt are now defined on negative real
  5476 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  5477 Nonnegativity side conditions have been removed from many lemmas, so
  5478 that more subgoals may now be solved by simplification; potential
  5479 INCOMPATIBILITY.
  5480 
  5481 * Real: new type classes formalize real normed vector spaces and
  5482 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  5483 and norm :: 'a => real.
  5484 
  5485 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  5486 reals into other types. The overloaded constant Reals :: 'a set is now
  5487 defined as range of_real; potential INCOMPATIBILITY.
  5488 
  5489 * Real: proper support for ML code generation, including 'quickcheck'.
  5490 Reals are implemented as arbitrary precision rationals.
  5491 
  5492 * Hyperreal: Several constants that previously worked only for the
  5493 reals have been generalized, so they now work over arbitrary vector
  5494 spaces. Type annotations may need to be added in some cases; potential
  5495 INCOMPATIBILITY.
  5496 
  5497   Infinitesimal  :: ('a::real_normed_vector) star set
  5498   HFinite        :: ('a::real_normed_vector) star set
  5499   HInfinite      :: ('a::real_normed_vector) star set
  5500   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5501   monad          :: ('a::real_normed_vector) star => 'a star set
  5502   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5503   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5504   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5505   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5506   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5507   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5508   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5509   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5510   sgn            :: 'a::real_normed_vector => 'a
  5511   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5512 
  5513 * Complex: Some complex-specific constants are now abbreviations for
  5514 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5515 hnorm.  Other constants have been entirely removed in favor of the
  5516 polymorphic versions (INCOMPATIBILITY):
  5517 
  5518   approx        <-- capprox
  5519   HFinite       <-- CFinite
  5520   HInfinite     <-- CInfinite
  5521   Infinitesimal <-- CInfinitesimal
  5522   monad         <-- cmonad
  5523   galaxy        <-- cgalaxy
  5524   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5525   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5526   (ns)deriv     <-- (ns)cderiv
  5527 
  5528 
  5529 *** HOL-Algebra ***
  5530 
  5531 * Formalisation of ideals and the quotient construction over rings.
  5532 
  5533 * Order and lattice theory no longer based on records.
  5534 INCOMPATIBILITY.
  5535 
  5536 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5537 greatest_closed.  INCOMPATIBILITY.
  5538 
  5539 * Method algebra is now set up via an attribute.  For examples see
  5540 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5541 of algebraic structures.
  5542 
  5543 * Renamed theory CRing to Ring.
  5544 
  5545 
  5546 *** HOL-Nominal ***
  5547 
  5548 * Substantial, yet incomplete support for nominal datatypes (binding
  5549 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5550 src/HOL/Nominal/Examples.  Prospective users should consult
  5551 http://isabelle.in.tum.de/nominal/
  5552 
  5553 
  5554 *** ML ***
  5555 
  5556 * ML basics: just one true type int, which coincides with IntInf.int
  5557 (even on SML/NJ).
  5558 
  5559 * ML within Isar: antiquotations allow to embed statically-checked
  5560 formal entities in the source, referring to the context available at
  5561 compile-time.  For example:
  5562 
  5563 ML {* @{sort "{zero,one}"} *}
  5564 ML {* @{typ "'a => 'b"} *}
  5565 ML {* @{term "%x. x"} *}
  5566 ML {* @{prop "x == y"} *}
  5567 ML {* @{ctyp "'a => 'b"} *}
  5568 ML {* @{cterm "%x. x"} *}
  5569 ML {* @{cprop "x == y"} *}
  5570 ML {* @{thm asm_rl} *}
  5571 ML {* @{thms asm_rl} *}
  5572 ML {* @{type_name c} *}
  5573 ML {* @{type_syntax c} *}
  5574 ML {* @{const_name c} *}
  5575 ML {* @{const_syntax c} *}
  5576 ML {* @{context} *}
  5577 ML {* @{theory} *}
  5578 ML {* @{theory Pure} *}
  5579 ML {* @{theory_ref} *}
  5580 ML {* @{theory_ref Pure} *}
  5581 ML {* @{simpset} *}
  5582 ML {* @{claset} *}
  5583 ML {* @{clasimpset} *}
  5584 
  5585 The same works for sources being ``used'' within an Isar context.
  5586 
  5587 * ML in Isar: improved error reporting; extra verbosity with
  5588 ML_Context.trace enabled.
  5589 
  5590 * Pure/General/table.ML: the join operations now works via exceptions
  5591 DUP/SAME instead of type option. This is simpler in simple cases, and
  5592 admits slightly more efficient complex applications.
  5593 
  5594 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5595 use Context.generic instead of just theory.
  5596 
  5597 * Pure: datatype Context.generic joins theory/Proof.context and
  5598 provides some facilities for code that works in either kind of
  5599 context, notably GenericDataFun for uniform theory and proof data.
  5600 
  5601 * Pure: simplified internal attribute type, which is now always
  5602 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5603 local (Proof.context) attributes have been discontinued, while
  5604 minimizing code duplication. Thm.rule_attribute and
  5605 Thm.declaration_attribute build canonical attributes; see also structure
  5606 Context for further operations on Context.generic, notably
  5607 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5608 declarations and definitions.
  5609 
  5610 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5611 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5612 init only required for impure data. INCOMPATIBILITY: empty really need
  5613 to be empty (no dependencies on theory content!)
  5614 
  5615 * Pure/kernel: consts certification ignores sort constraints given in
  5616 signature declarations. (This information is not relevant to the
  5617 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5618 potential INCOMPATIBILITY.
  5619 
  5620 * Pure: axiomatic type classes are now purely definitional, with
  5621 explicit proofs of class axioms and super class relations performed
  5622 internally. See Pure/axclass.ML for the main internal interfaces --
  5623 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5624 AxClass.axiomatize_class/classrel/arity supersede
  5625 Sign.add_classes/classrel/arities.
  5626 
  5627 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5628 global/local versions on theory vs. Proof.context have been
  5629 discontinued; Attrib.syntax and Method.syntax have been adapted
  5630 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5631 attributes, methods, etc.
  5632 
  5633 * Pure: several functions of signature "... -> theory -> theory * ..."
  5634 have been reoriented to "... -> theory -> ... * theory" in order to
  5635 allow natural usage in combination with the ||>, ||>>, |-> and
  5636 fold_map combinators.
  5637 
  5638 * Pure: official theorem names (closed derivations) and additional
  5639 comments (tags) are now strictly separate.  Name hints -- which are
  5640 maintained as tags -- may be attached any time without affecting the
  5641 derivation.
  5642 
  5643 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5644 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5645 achieve the old behaviour.
  5646 
  5647 * Pure: the "Goal" constant is now called "prop", supporting a
  5648 slightly more general idea of ``protecting'' meta-level rule
  5649 statements.
  5650 
  5651 * Pure: Logic.(un)varify only works in a global context, which is now
  5652 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5653 Logic.legacy_(un)varify as temporary workaround.
  5654 
  5655 * Pure: structure Name provides scalable operations for generating
  5656 internal variable names, notably Name.variants etc.  This replaces
  5657 some popular functions from term.ML:
  5658 
  5659   Term.variant		->  Name.variant
  5660   Term.variantlist	->  Name.variant_list
  5661   Term.invent_names	->  Name.invent_list
  5662 
  5663 Note that low-level renaming rarely occurs in new code -- operations
  5664 from structure Variable are used instead (see below).
  5665 
  5666 * Pure: structure Variable provides fundamental operations for proper
  5667 treatment of fixed/schematic variables in a context.  For example,
  5668 Variable.import introduces fixes for schematics of given facts and
  5669 Variable.export reverses the effect (up to renaming) -- this replaces
  5670 various freeze_thaw operations.
  5671 
  5672 * Pure: structure Goal provides simple interfaces for
  5673 init/conclude/finish and tactical prove operations (replacing former
  5674 Tactic.prove).  Goal.prove is the canonical way to prove results
  5675 within a given context; Goal.prove_global is a degraded version for
  5676 theory level goals, including a global Drule.standard.  Note that
  5677 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5678 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5679 in a locale context).
  5680 
  5681 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5682 and type checking (Syntax.check_term etc.), with common combinations
  5683 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5684 which are considered legacy and await removal.
  5685 
  5686 * Pure/Syntax: generic interfaces for type unchecking
  5687 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5688 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5689 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5690 available for convenience, but refer to the very same operations using
  5691 a mere theory instead of a full context.
  5692 
  5693 * Isar: simplified treatment of user-level errors, using exception
  5694 ERROR of string uniformly.  Function error now merely raises ERROR,
  5695 without any side effect on output channels.  The Isar toplevel takes
  5696 care of proper display of ERROR exceptions.  ML code may use plain
  5697 handle/can/try; cat_error may be used to concatenate errors like this:
  5698 
  5699   ... handle ERROR msg => cat_error msg "..."
  5700 
  5701 Toplevel ML code (run directly or through the Isar toplevel) may be
  5702 embedded into the Isar toplevel with exception display/debug like
  5703 this:
  5704 
  5705   Isar.toplevel (fn () => ...)
  5706 
  5707 INCOMPATIBILITY, removed special transform_error facilities, removed
  5708 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5709 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5710 -- use plain ERROR instead.
  5711 
  5712 * Isar: theory setup now has type (theory -> theory), instead of a
  5713 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5714 
  5715 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5716 ProofContext.debug/verbose flags.
  5717 
  5718 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5719 theory before entering a proof state.  Transactions now always see a
  5720 quasi-functional intermediate checkpoint, both in interactive and
  5721 batch mode.
  5722 
  5723 * Isar: simplified interfaces for outer syntax.  Renamed
  5724 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5725 OuterSyntax.add_parsers -- this functionality is now included in
  5726 OuterSyntax.command etc.  INCOMPATIBILITY.
  5727 
  5728 * Simplifier: the simpset of a running simplification process now
  5729 contains a proof context (cf. Simplifier.the_context), which is the
  5730 very context that the initial simpset has been retrieved from (by
  5731 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5732 (solver, looper etc.) may depend on arbitrary proof data.
  5733 
  5734 * Simplifier.inherit_context inherits the proof context (plus the
  5735 local bounds) of the current simplification process; any simproc
  5736 etc. that calls the Simplifier recursively should do this!  Removed
  5737 former Simplifier.inherit_bounds, which is already included here --
  5738 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5739 specify an explicit context using Simplifier.context/theory_context.
  5740 
  5741 * Simplifier/Classical Reasoner: more abstract interfaces
  5742 change_simpset/claset for modifying the simpset/claset reference of a
  5743 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5744 INCOMPATIBILITY.
  5745 
  5746 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5747 "Trueprop" etc.
  5748 
  5749 
  5750 *** System ***
  5751 
  5752 * settings: the default heap location within ISABELLE_HOME_USER now
  5753 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5754 Isabelle installations.
  5755 
  5756 * isabelle-process: option -S (secure mode) disables some critical
  5757 operations, notably runtime compilation and evaluation of ML source
  5758 code.
  5759 
  5760 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5761 
  5762 * Support for parallel execution, using native multicore support of
  5763 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5764 independent theories, according to the given theory header
  5765 specifications. The maximum number of worker threads is specified via
  5766 usedir option -M or the "max-threads" setting in Proof General. A
  5767 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5768 to 6 on a 8-core machine.  User-code needs to observe certain
  5769 guidelines for thread-safe programming, see appendix A in the Isar
  5770 Implementation manual.
  5771 
  5772 
  5773 
  5774 New in Isabelle2005 (October 2005)
  5775 ----------------------------------
  5776 
  5777 *** General ***
  5778 
  5779 * Theory headers: the new header syntax for Isar theories is
  5780 
  5781   theory <name>
  5782   imports <theory1> ... <theoryN>
  5783   uses <file1> ... <fileM>
  5784   begin
  5785 
  5786 where the 'uses' part is optional.  The previous syntax
  5787 
  5788   theory <name> = <theory1> + ... + <theoryN>:
  5789 
  5790 will disappear in the next release.  Use isatool fixheaders to convert
  5791 existing theory files.  Note that there is no change in ancient
  5792 non-Isar theories now, but these will disappear soon.
  5793 
  5794 * Theory loader: parent theories can now also be referred to via
  5795 relative and absolute paths.
  5796 
  5797 * Command 'find_theorems' searches for a list of criteria instead of a
  5798 list of constants. Known criteria are: intro, elim, dest, name:string,
  5799 simp:term, and any term. Criteria can be preceded by '-' to select
  5800 theorems that do not match. Intro, elim, dest select theorems that
  5801 match the current goal, name:s selects theorems whose fully qualified
  5802 name contain s, and simp:term selects all simplification rules whose
  5803 lhs match term.  Any other term is interpreted as pattern and selects
  5804 all theorems matching the pattern. Available in ProofGeneral under
  5805 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5806 
  5807   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5808 
  5809 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5810 matching the current goal as introduction rule and not having "HOL."
  5811 in their name (i.e. not being defined in theory HOL).
  5812 
  5813 * Command 'thms_containing' has been discontinued in favour of
  5814 'find_theorems'; INCOMPATIBILITY.
  5815 
  5816 * Communication with Proof General is now 8bit clean, which means that
  5817 Unicode text in UTF-8 encoding may be used within theory texts (both
  5818 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5819 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5820 
  5821   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5822   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5823 
  5824 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5825 Classical Reasoner.  Typical big applications run around 2 times
  5826 faster.
  5827 
  5828 
  5829 *** Document preparation ***
  5830 
  5831 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5832 of raw sources.  Only those symbols that do not require additional
  5833 LaTeX packages (depending on comments in isabellesym.sty) are
  5834 displayed properly, everything else is left verbatim.  isatool display
  5835 and isatool print are used as front ends (these are subject to the
  5836 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5837 
  5838 * Command tags control specific markup of certain regions of text,
  5839 notably folding and hiding.  Predefined tags include "theory" (for
  5840 theory begin and end), "proof" for proof commands, and "ML" for
  5841 commands involving ML code; the additional tags "visible" and
  5842 "invisible" are unused by default.  Users may give explicit tag
  5843 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5844 interpretation of tags is determined by the LaTeX job during document
  5845 preparation: see option -V of isatool usedir, or options -n and -t of
  5846 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5847 \isadroptag.
  5848 
  5849 Several document versions may be produced at the same time via isatool
  5850 usedir (the generated index.html will link all of them).  Typical
  5851 specifications include ''-V document=theory,proof,ML'' to present
  5852 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5853 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5854 these parts without any formal replacement text.  The Isabelle site
  5855 default settings produce ''document'' and ''outline'' versions as
  5856 specified above.
  5857 
  5858 * Several new antiquotations:
  5859 
  5860   @{term_type term} prints a term with its type annotated;
  5861 
  5862   @{typeof term} prints the type of a term;
  5863 
  5864   @{const const} is the same as @{term const}, but checks that the
  5865   argument is a known logical constant;
  5866 
  5867   @{term_style style term} and @{thm_style style thm} print a term or
  5868   theorem applying a "style" to it
  5869 
  5870   @{ML text}
  5871 
  5872 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5873 definitions, equations, inequations etc., 'concl' printing only the
  5874 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5875 to print the specified premise.  TermStyle.add_style provides an ML
  5876 interface for introducing further styles.  See also the "LaTeX Sugar"
  5877 document practical applications.  The ML antiquotation prints
  5878 type-checked ML expressions verbatim.
  5879 
  5880 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5881 and 'text' support optional locale specification '(in loc)', which
  5882 specifies the default context for interpreting antiquotations.  For
  5883 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5884 
  5885 * Option 'locale=NAME' of antiquotations specifies an alternative
  5886 context interpreting the subsequent argument.  For example: @{thm
  5887 [locale=lattice] inf_assoc}.
  5888 
  5889 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5890 a proof context.
  5891 
  5892 * Proper output of antiquotations for theory commands involving a
  5893 proof context (such as 'locale' or 'theorem (in loc) ...').
  5894 
  5895 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5896 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5897 
  5898 * isatool usedir: new option -C (default true) controls whether option
  5899 -D should include a copy of the original document directory; -C false
  5900 prevents unwanted effects such as copying of administrative CVS data.
  5901 
  5902 
  5903 *** Pure ***
  5904 
  5905 * Considerably improved version of 'constdefs' command.  Now performs
  5906 automatic type-inference of declared constants; additional support for
  5907 local structure declarations (cf. locales and HOL records), see also
  5908 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5909 sequential dependencies of definitions within a single 'constdefs'
  5910 section; moreover, the declared name needs to be an identifier.  If
  5911 all fails, consider to fall back on 'consts' and 'defs' separately.
  5912 
  5913 * Improved indexed syntax and implicit structures.  First of all,
  5914 indexed syntax provides a notational device for subscripted
  5915 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5916 expressions.  Secondly, in a local context with structure
  5917 declarations, number indexes \<^sub>n or the empty index (default
  5918 number 1) refer to a certain fixed variable implicitly; option
  5919 show_structs controls printing of implicit structures.  Typical
  5920 applications of these concepts involve record types and locales.
  5921 
  5922 * New command 'no_syntax' removes grammar declarations (and
  5923 translations) resulting from the given syntax specification, which is
  5924 interpreted in the same manner as for the 'syntax' command.
  5925 
  5926 * 'Advanced' translation functions (parse_translation etc.) may depend
  5927 on the signature of the theory context being presently used for
  5928 parsing/printing, see also isar-ref manual.
  5929 
  5930 * Improved 'oracle' command provides a type-safe interface to turn an
  5931 ML expression of type theory -> T -> term into a primitive rule of
  5932 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5933 is already included here); see also FOL/ex/IffExample.thy;
  5934 INCOMPATIBILITY.
  5935 
  5936 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5937 before); "cI" is no longer bound, use "c.intro" instead.
  5938 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5939 axclasses vs. locales.
  5940 
  5941 * Improved internal renaming of symbolic identifiers -- attach primes
  5942 instead of base 26 numbers.
  5943 
  5944 * New flag show_question_marks controls printing of leading question
  5945 marks in schematic variable names.
  5946 
  5947 * In schematic variable names, *any* symbol following \<^isub> or
  5948 \<^isup> is now treated as part of the base name.  For example, the
  5949 following works without printing of awkward ".0" indexes:
  5950 
  5951   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5952     by simp
  5953 
  5954 * Inner syntax includes (*(*nested*) comments*).
  5955 
  5956 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5957 annotations as "(00...)".
  5958 
  5959 * Clear separation of logical types and nonterminals, where the latter
  5960 may only occur in 'syntax' specifications or type abbreviations.
  5961 Before that distinction was only partially implemented via type class
  5962 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5963 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5964 exotic syntax specifications may require further adaption
  5965 (e.g. Cube/Cube.thy).
  5966 
  5967 * Removed obsolete type class "logic", use the top sort {} instead.
  5968 Note that non-logical types should be declared as 'nonterminals'
  5969 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5970 specifications.
  5971 
  5972 * Attributes 'induct' and 'cases': type or set names may now be
  5973 locally fixed variables as well.
  5974 
  5975 * Simplifier: can now control the depth to which conditional rewriting
  5976 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5977 Limit.
  5978 
  5979 * Simplifier: simplification procedures may now take the current
  5980 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5981 interface), which is very useful for calling the Simplifier
  5982 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5983 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5984 low-level mk_simproc no longer applies Logic.varify internally, to
  5985 allow for use in a context of fixed variables.
  5986 
  5987 * thin_tac now works even if the assumption being deleted contains !!
  5988 or ==>.  More generally, erule now works even if the major premise of
  5989 the elimination rule contains !! or ==>.
  5990 
  5991 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5992 
  5993 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5994 from Pure, which contains all common declarations already.  Both
  5995 theories are defined via plain Isabelle/Isar .thy files.
  5996 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5997 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5998 use isatool fixcpure to adapt your theory and ML sources.
  5999 
  6000 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  6001 selections of theorems in named facts via index ranges.
  6002 
  6003 * 'print_theorems': in theory mode, really print the difference
  6004 wrt. the last state (works for interactive theory development only),
  6005 in proof mode print all local facts (cf. 'print_facts');
  6006 
  6007 * 'hide': option '(open)' hides only base names.
  6008 
  6009 * More efficient treatment of intermediate checkpoints in interactive
  6010 theory development.
  6011 
  6012 * Code generator is now invoked via code_module (incremental code
  6013 generation) and code_library (modular code generation, ML structures
  6014 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  6015 must be quoted when used as identifiers.
  6016 
  6017 * New 'value' command for reading, evaluating and printing terms using
  6018 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  6019 quoted when used as identifier.
  6020 
  6021 
  6022 *** Locales ***
  6023 
  6024 * New commands for the interpretation of locale expressions in
  6025 theories (1), locales (2) and proof contexts (3).  These generate
  6026 proof obligations from the expression specification.  After the
  6027 obligations have been discharged, theorems of the expression are added
  6028 to the theory, target locale or proof context.  The synopsis of the
  6029 commands is a follows:
  6030 
  6031   (1) interpretation expr inst
  6032   (2) interpretation target < expr
  6033   (3) interpret expr inst
  6034 
  6035 Interpretation in theories and proof contexts require a parameter
  6036 instantiation of terms from the current context.  This is applied to
  6037 specifications and theorems of the interpreted expression.
  6038 Interpretation in locales only permits parameter renaming through the
  6039 locale expression.  Interpretation is smart in that interpretations
  6040 that are active already do not occur in proof obligations, neither are
  6041 instantiated theorems stored in duplicate.  Use 'print_interps' to
  6042 inspect active interpretations of a particular locale.  For details,
  6043 see the Isar Reference manual.  Examples can be found in
  6044 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  6045 
  6046 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  6047 'interpret' instead.
  6048 
  6049 * New context element 'constrains' for adding type constraints to
  6050 parameters.
  6051 
  6052 * Context expressions: renaming of parameters with syntax
  6053 redeclaration.
  6054 
  6055 * Locale declaration: 'includes' disallowed.
  6056 
  6057 * Proper static binding of attribute syntax -- i.e. types / terms /
  6058 facts mentioned as arguments are always those of the locale definition
  6059 context, independently of the context of later invocations.  Moreover,
  6060 locale operations (renaming and type / term instantiation) are applied
  6061 to attribute arguments as expected.
  6062 
  6063 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  6064 actual attributes; rare situations may require Attrib.attribute to
  6065 embed those attributes into Attrib.src that lack concrete syntax.
  6066 Attribute implementations need to cooperate properly with the static
  6067 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  6068 Attrib.XXX_thm etc. already do the right thing without further
  6069 intervention.  Only unusual applications -- such as "where" or "of"
  6070 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  6071 on the context and the facts involved -- may have to assign parsed
  6072 values to argument tokens explicitly.
  6073 
  6074 * Changed parameter management in theorem generation for long goal
  6075 statements with 'includes'.  INCOMPATIBILITY: produces a different
  6076 theorem statement in rare situations.
  6077 
  6078 * Locale inspection command 'print_locale' omits notes elements.  Use
  6079 'print_locale!' to have them included in the output.
  6080 
  6081 
  6082 *** Provers ***
  6083 
  6084 * Provers/hypsubst.ML: improved version of the subst method, for
  6085 single-step rewriting: it now works in bound variable contexts. New is
  6086 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  6087 rewrite a different subterm than the original subst method, which is
  6088 still available as 'simplesubst'.
  6089 
  6090 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  6091 and quasi orders.
  6092 
  6093 * Provers/trancl.ML: new transitivity reasoner for transitive and
  6094 reflexive-transitive closure of relations.
  6095 
  6096 * Provers/blast.ML: new reference depth_limit to make blast's depth
  6097 limit (previously hard-coded with a value of 20) user-definable.
  6098 
  6099 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  6100 is peformed already.  Object-logics merely need to finish their
  6101 initial simpset configuration as before.  INCOMPATIBILITY.
  6102 
  6103 
  6104 *** HOL ***
  6105 
  6106 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  6107 
  6108   syntax (epsilon)
  6109     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  6110 
  6111 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  6112 and x-symbol; use option '-m epsilon' to get it actually printed.
  6113 Moreover, the mathematically important symbolic identifier \<epsilon>
  6114 becomes available as variable, constant etc.  INCOMPATIBILITY,
  6115 
  6116 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  6117 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  6118 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  6119 support corresponding Isar calculations.
  6120 
  6121 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  6122 instead of ":".
  6123 
  6124 * theory SetInterval: changed the syntax for open intervals:
  6125 
  6126   Old       New
  6127   {..n(}    {..<n}
  6128   {)n..}    {n<..}
  6129   {m..n(}   {m..<n}
  6130   {)m..n}   {m<..n}
  6131   {)m..n(}  {m<..<n}
  6132 
  6133 The old syntax is still supported but will disappear in the next
  6134 release.  For conversion use the following Emacs search and replace
  6135 patterns (these are not perfect but work quite well):
  6136 
  6137   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  6138   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  6139 
  6140 * Theory Commutative_Ring (in Library): method comm_ring for proving
  6141 equalities in commutative rings; method 'algebra' provides a generic
  6142 interface.
  6143 
  6144 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  6145 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  6146 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  6147 be a tuple pattern.
  6148 
  6149 Some new syntax forms are available:
  6150 
  6151   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  6152   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  6153   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  6154   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  6155 
  6156 The latter form "\<Sum>x < k. e" used to be based on a separate
  6157 function "Summation", which has been discontinued.
  6158 
  6159 * theory Finite_Set: in structured induction proofs, the insert case
  6160 is now 'case (insert x F)' instead of the old counterintuitive 'case
  6161 (insert F x)'.
  6162 
  6163 * The 'refute' command has been extended to support a much larger
  6164 fragment of HOL, including axiomatic type classes, constdefs and
  6165 typedefs, inductive datatypes and recursion.
  6166 
  6167 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  6168 Requires zChaff with proof generation to be installed.  See
  6169 HOL/ex/SAT_Examples.thy for examples.
  6170 
  6171 * Datatype induction via method 'induct' now preserves the name of the
  6172 induction variable. For example, when proving P(xs::'a list) by
  6173 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  6174 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  6175 in unstructured proof scripts.
  6176 
  6177 * Reworked implementation of records.  Improved scalability for
  6178 records with many fields, avoiding performance problems for type
  6179 inference. Records are no longer composed of nested field types, but
  6180 of nested extension types. Therefore the record type only grows linear
  6181 in the number of extensions and not in the number of fields.  The
  6182 top-level (users) view on records is preserved.  Potential
  6183 INCOMPATIBILITY only in strange cases, where the theory depends on the
  6184 old record representation. The type generated for a record is called
  6185 <record_name>_ext_type.
  6186 
  6187 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  6188 proofs triggered by a record definition or a simproc (if
  6189 quick_and_dirty is enabled).  Definitions of large records can take
  6190 quite long.
  6191 
  6192 New simproc record_upd_simproc for simplification of multiple record
  6193 updates enabled by default.  Moreover, trivial updates are also
  6194 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  6195 occasionally, since simplification is more powerful by default.
  6196 
  6197 * typedef: proper support for polymorphic sets, which contain extra
  6198 type-variables in the term.
  6199 
  6200 * Simplifier: automatically reasons about transitivity chains
  6201 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  6202 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  6203 old proofs break occasionally as simplification may now solve more
  6204 goals than previously.
  6205 
  6206 * Simplifier: converts x <= y into x = y if assumption y <= x is
  6207 present.  Works for all partial orders (class "order"), in particular
  6208 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  6209 just like y <= x.
  6210 
  6211 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  6212 bound variable or a constant then the let is unfolded.  Otherwise
  6213 first a is simplified to b, and then f b is simplified to g. If
  6214 possible we abstract b from g arriving at "let x = b in h x",
  6215 otherwise we unfold the let and arrive at g.  The simproc can be
  6216 enabled/disabled by the reference use_let_simproc.  Potential
  6217 INCOMPATIBILITY since simplification is more powerful by default.
  6218 
  6219 * Classical reasoning: the meson method now accepts theorems as arguments.
  6220 
  6221 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  6222 jobs to provide advice on the provability of subgoals.
  6223 
  6224 * Theory OrderedGroup and Ring_and_Field: various additions and
  6225 improvements to faciliate calculations involving equalities and
  6226 inequalities.
  6227 
  6228 The following theorems have been eliminated or modified
  6229 (INCOMPATIBILITY):
  6230 
  6231   abs_eq             now named abs_of_nonneg
  6232   abs_of_ge_0        now named abs_of_nonneg
  6233   abs_minus_eq       now named abs_of_nonpos
  6234   imp_abs_id         now named abs_of_nonneg
  6235   imp_abs_neg_id     now named abs_of_nonpos
  6236   mult_pos           now named mult_pos_pos
  6237   mult_pos_le        now named mult_nonneg_nonneg
  6238   mult_pos_neg_le    now named mult_nonneg_nonpos
  6239   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  6240   mult_neg           now named mult_neg_neg
  6241   mult_neg_le        now named mult_nonpos_nonpos
  6242 
  6243 * The following lemmas in Ring_and_Field have been added to the simplifier:
  6244      
  6245      zero_le_square
  6246      not_square_less_zero 
  6247 
  6248   The following lemmas have been deleted from Real/RealPow:
  6249   
  6250      realpow_zero_zero
  6251      realpow_two
  6252      realpow_less
  6253      zero_le_power
  6254      realpow_two_le
  6255      abs_realpow_two
  6256      realpow_two_abs     
  6257 
  6258 * Theory Parity: added rules for simplifying exponents.
  6259 
  6260 * Theory List:
  6261 
  6262 The following theorems have been eliminated or modified
  6263 (INCOMPATIBILITY):
  6264 
  6265   list_all_Nil       now named list_all.simps(1)
  6266   list_all_Cons      now named list_all.simps(2)
  6267   list_all_conv      now named list_all_iff
  6268   set_mem_eq         now named mem_iff
  6269 
  6270 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  6271 asymptotic "big O" calculations.  See the notes in BigO.thy.
  6272 
  6273 
  6274 *** HOL-Complex ***
  6275 
  6276 * Theory RealDef: better support for embedding natural numbers and
  6277 integers in the reals.
  6278 
  6279 The following theorems have been eliminated or modified
  6280 (INCOMPATIBILITY):
  6281 
  6282   exp_ge_add_one_self  now requires no hypotheses
  6283   real_of_int_add      reversed direction of equality (use [symmetric])
  6284   real_of_int_minus    reversed direction of equality (use [symmetric])
  6285   real_of_int_diff     reversed direction of equality (use [symmetric])
  6286   real_of_int_mult     reversed direction of equality (use [symmetric])
  6287 
  6288 * Theory RComplete: expanded support for floor and ceiling functions.
  6289 
  6290 * Theory Ln is new, with properties of the natural logarithm
  6291 
  6292 * Hyperreal: There is a new type constructor "star" for making
  6293 nonstandard types.  The old type names are now type synonyms:
  6294 
  6295   hypreal = real star
  6296   hypnat = nat star
  6297   hcomplex = complex star
  6298 
  6299 * Hyperreal: Many groups of similarly-defined constants have been
  6300 replaced by polymorphic versions (INCOMPATIBILITY):
  6301 
  6302   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  6303 
  6304   starset      <-- starsetNat, starsetC
  6305   *s*          <-- *sNat*, *sc*
  6306   starset_n    <-- starsetNat_n, starsetC_n
  6307   *sn*         <-- *sNatn*, *scn*
  6308   InternalSets <-- InternalNatSets, InternalCSets
  6309 
  6310   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  6311   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  6312   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  6313   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  6314   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  6315 
  6316 * Hyperreal: Many type-specific theorems have been removed in favor of
  6317 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  6318 
  6319   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  6320   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  6321   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  6322   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  6323   right_minus <-- hypreal_add_minus
  6324   left_minus <-- {hypreal,hcomplex}_add_minus_left
  6325   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  6326   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  6327   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  6328   mult_1_right <-- hcomplex_mult_one_right
  6329   mult_zero_left <-- hcomplex_mult_zero_left
  6330   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  6331   right_distrib <-- hypnat_add_mult_distrib2
  6332   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  6333   right_inverse <-- hypreal_mult_inverse
  6334   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  6335   order_refl <-- {hypreal,hypnat}_le_refl
  6336   order_trans <-- {hypreal,hypnat}_le_trans
  6337   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  6338   order_less_le <-- {hypreal,hypnat}_less_le
  6339   linorder_linear <-- {hypreal,hypnat}_le_linear
  6340   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  6341   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  6342   add_nonneg_nonneg <-- hypreal_le_add_order
  6343 
  6344 * Hyperreal: Separate theorems having to do with type-specific
  6345 versions of constants have been merged into theorems that apply to the
  6346 new polymorphic constants (INCOMPATIBILITY):
  6347 
  6348   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  6349   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  6350   STAR_Un <-- {STAR,NatStar,STARC}_Un
  6351   STAR_Int <-- {STAR,NatStar,STARC}_Int
  6352   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  6353   STAR_subset <-- {STAR,NatStar,STARC}_subset
  6354   STAR_mem <-- {STAR,NatStar,STARC}_mem
  6355   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  6356   STAR_diff <-- {STAR,STARC}_diff
  6357   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  6358     STARC_hcomplex_of_complex}_image_subset
  6359   starset_n_Un <-- starset{Nat,C}_n_Un
  6360   starset_n_Int <-- starset{Nat,C}_n_Int
  6361   starset_n_Compl <-- starset{Nat,C}_n_Compl
  6362   starset_n_diff <-- starset{Nat,C}_n_diff
  6363   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  6364   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  6365   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  6366   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  6367   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  6368   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  6369   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  6370   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  6371   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  6372   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  6373   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  6374   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  6375   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  6376   starfun_diff <-- starfun{C,RC,CR}_diff
  6377   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  6378   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  6379   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  6380   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  6381   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  6382   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  6383   starfun_Id <-- starfunC_Id
  6384   starfun_approx <-- starfun{Nat,CR}_approx
  6385   starfun_capprox <-- starfun{C,RC}_capprox
  6386   starfun_abs <-- starfunNat_rabs
  6387   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  6388   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  6389   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  6390   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  6391   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  6392   starfun_add_approx <-- starfunCR_add_approx
  6393   starfun_inverse_inverse <-- starfunC_inverse_inverse
  6394   starfun_divide <-- starfun{C,CR,RC}_divide
  6395   starfun_n <-- starfun{Nat,C}_n
  6396   starfun_n_mult <-- starfun{Nat,C}_n_mult
  6397   starfun_n_add <-- starfun{Nat,C}_n_add
  6398   starfun_n_add_minus <-- starfunNat_n_add_minus
  6399   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  6400   starfun_n_minus <-- starfun{Nat,C}_n_minus
  6401   starfun_n_eq <-- starfun{Nat,C}_n_eq
  6402 
  6403   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  6404   star_n_minus <-- {hypreal,hcomplex}_minus
  6405   star_n_diff <-- {hypreal,hcomplex}_diff
  6406   star_n_mult <-- {hypreal,hcomplex}_mult
  6407   star_n_inverse <-- {hypreal,hcomplex}_inverse
  6408   star_n_le <-- {hypreal,hypnat}_le
  6409   star_n_less <-- {hypreal,hypnat}_less
  6410   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  6411   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  6412   star_n_abs <-- hypreal_hrabs
  6413   star_n_divide <-- hcomplex_divide
  6414 
  6415   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  6416   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  6417   star_of_diff <-- hypreal_of_real_diff
  6418   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  6419   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  6420   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  6421   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  6422   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  6423   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  6424   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  6425   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  6426   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  6427   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  6428   star_of_number_of <-- {hypreal,hcomplex}_number_of
  6429   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  6430   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  6431   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  6432   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  6433   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  6434   star_of_power <-- hypreal_of_real_power
  6435   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  6436 
  6437 * Hyperreal: new method "transfer" that implements the transfer
  6438 principle of nonstandard analysis. With a subgoal that mentions
  6439 nonstandard types like "'a star", the command "apply transfer"
  6440 replaces it with an equivalent one that mentions only standard types.
  6441 To be successful, all free variables must have standard types; non-
  6442 standard variables must have explicit universal quantifiers.
  6443 
  6444 * Hyperreal: A theory of Taylor series.
  6445 
  6446 
  6447 *** HOLCF ***
  6448 
  6449 * Discontinued special version of 'constdefs' (which used to support
  6450 continuous functions) in favor of the general Pure one with full
  6451 type-inference.
  6452 
  6453 * New simplification procedure for solving continuity conditions; it
  6454 is much faster on terms with many nested lambda abstractions (cubic
  6455 instead of exponential time).
  6456 
  6457 * New syntax for domain package: selector names are now optional.
  6458 Parentheses should be omitted unless argument is lazy, for example:
  6459 
  6460   domain 'a stream = cons "'a" (lazy "'a stream")
  6461 
  6462 * New command 'fixrec' for defining recursive functions with pattern
  6463 matching; defining multiple functions with mutual recursion is also
  6464 supported.  Patterns may include the constants cpair, spair, up, sinl,
  6465 sinr, or any data constructor defined by the domain package. The given
  6466 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  6467 syntax and examples.
  6468 
  6469 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  6470 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  6471 but the proof obligation additionally includes an admissibility
  6472 requirement. The packages generate instances of class cpo or pcpo,
  6473 with continuity and strictness theorems for Rep and Abs.
  6474 
  6475 * HOLCF: Many theorems have been renamed according to a more standard naming
  6476 scheme (INCOMPATIBILITY):
  6477 
  6478   foo_inject:  "foo$x = foo$y ==> x = y"
  6479   foo_eq:      "(foo$x = foo$y) = (x = y)"
  6480   foo_less:    "(foo$x << foo$y) = (x << y)"
  6481   foo_strict:  "foo$UU = UU"
  6482   foo_defined: "... ==> foo$x ~= UU"
  6483   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  6484 
  6485 
  6486 *** ZF ***
  6487 
  6488 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  6489 including the First Isomorphism Theorem (on quotienting by the kernel
  6490 of a homomorphism).
  6491 
  6492 * ZF/Simplifier: install second copy of type solver that actually
  6493 makes use of TC rules declared to Isar proof contexts (or locales);
  6494 the old version is still required for ML proof scripts.
  6495 
  6496 
  6497 *** Cube ***
  6498 
  6499 * Converted to Isar theory format; use locales instead of axiomatic
  6500 theories.
  6501 
  6502 
  6503 *** ML ***
  6504 
  6505 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6506 for ||>, ||>>, |>>,
  6507 
  6508 * Pure/library.ML no longer defines its own option datatype, but uses
  6509 that of the SML basis, which has constructors NONE and SOME instead of
  6510 None and Some, as well as exception Option.Option instead of OPTION.
  6511 The functions the, if_none, is_some, is_none have been adapted
  6512 accordingly, while Option.map replaces apsome.
  6513 
  6514 * Pure/library.ML: the exception LIST has been given up in favour of
  6515 the standard exceptions Empty and Subscript, as well as
  6516 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6517 superceded by the standard hd and tl functions etc.
  6518 
  6519 A number of basic list functions are no longer exported to the ML
  6520 toplevel, as they are variants of predefined functions.  The following
  6521 suggests how one can translate existing code:
  6522 
  6523     rev_append xs ys = List.revAppend (xs, ys)
  6524     nth_elem (i, xs) = List.nth (xs, i)
  6525     last_elem xs = List.last xs
  6526     flat xss = List.concat xss
  6527     seq fs = List.app fs
  6528     partition P xs = List.partition P xs
  6529     mapfilter f xs = List.mapPartial f xs
  6530 
  6531 * Pure/library.ML: several combinators for linear functional
  6532 transformations, notably reverse application and composition:
  6533 
  6534   x |> f                f #> g
  6535   (x, y) |-> f          f #-> g
  6536 
  6537 * Pure/library.ML: introduced/changed precedence of infix operators:
  6538 
  6539   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6540   infix 2 ?;
  6541   infix 3 o oo ooo oooo;
  6542   infix 4 ~~ upto downto;
  6543 
  6544 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6545 infix operators.
  6546 
  6547 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6548 fold_map support linear functional transformations and nesting.  For
  6549 example:
  6550 
  6551   fold f [x1, ..., xN] y =
  6552     y |> f x1 |> ... |> f xN
  6553 
  6554   (fold o fold) f [xs1, ..., xsN] y =
  6555     y |> fold f xs1 |> ... |> fold f xsN
  6556 
  6557   fold f [x1, ..., xN] =
  6558     f x1 #> ... #> f xN
  6559 
  6560   (fold o fold) f [xs1, ..., xsN] =
  6561     fold f xs1 #> ... #> fold f xsN
  6562 
  6563 * Pure/library.ML: the following selectors on type 'a option are
  6564 available:
  6565 
  6566   the:               'a option -> 'a  (*partial*)
  6567   these:             'a option -> 'a  where 'a = 'b list
  6568   the_default: 'a -> 'a option -> 'a
  6569   the_list:          'a option -> 'a list
  6570 
  6571 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6572 basic operations for association lists, following natural argument
  6573 order; moreover the explicit equality predicate passed here avoids
  6574 potentially expensive polymorphic runtime equality checks.
  6575 The old functions may be expressed as follows:
  6576 
  6577   assoc = uncurry (AList.lookup (op =))
  6578   assocs = these oo AList.lookup (op =)
  6579   overwrite = uncurry (AList.update (op =)) o swap
  6580 
  6581 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6582 
  6583   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6584   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6585 
  6586 replacing make_keylist and keyfilter (occassionally used)
  6587 Naive rewrites:
  6588 
  6589   make_keylist = AList.make
  6590   keyfilter = AList.find (op =)
  6591 
  6592 * eq_fst and eq_snd now take explicit equality parameter, thus
  6593   avoiding eqtypes. Naive rewrites:
  6594 
  6595     eq_fst = eq_fst (op =)
  6596     eq_snd = eq_snd (op =)
  6597 
  6598 * Removed deprecated apl and apr (rarely used).
  6599   Naive rewrites:
  6600 
  6601     apl (n, op) =>>= curry op n
  6602     apr (op, m) =>>= fn n => op (n, m)
  6603 
  6604 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6605 provides a reasonably efficient light-weight implementation of sets as
  6606 lists.
  6607 
  6608 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6609 few new operations; existing lookup and update are now curried to
  6610 follow natural argument order (for use with fold etc.);
  6611 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6612 
  6613 * Pure/General: output via the Isabelle channels of
  6614 writeln/warning/error etc. is now passed through Output.output, with a
  6615 hook for arbitrary transformations depending on the print_mode
  6616 (cf. Output.add_mode -- the first active mode that provides a output
  6617 function wins).  Already formatted output may be embedded into further
  6618 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6619 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6620 accommodate easy composition of diagnostic messages etc.  Programmers
  6621 rarely need to care about Output.output or Output.raw at all, with
  6622 some notable exceptions: Output.output is required when bypassing the
  6623 standard channels (writeln etc.), or in token translations to produce
  6624 properly formatted results; Output.raw is required when capturing
  6625 already output material that will eventually be presented to the user
  6626 a second time.  For the default print mode, both Output.output and
  6627 Output.raw have no effect.
  6628 
  6629 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6630 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6631 cumulative results are displayed at the end of a batch session.
  6632 
  6633 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6634 replaced by File.platform_path and File.shell_path (with appropriate
  6635 hooks).  This provides a clean interface for unusual systems where the
  6636 internal and external process view of file names are different.
  6637 
  6638 * Pure: more efficient orders for basic syntactic entities: added
  6639 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6640 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6641 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6642 orders now -- potential INCOMPATIBILITY for code that depends on a
  6643 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6644 Library.sort_strings on result).
  6645 
  6646 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6647 fold_types traverse types/terms from left to right, observing natural
  6648 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6649 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6650 
  6651 * Pure: name spaces have been refined, with significant changes of the
  6652 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6653 to extern(_table).  The plain name entry path is superceded by a
  6654 general 'naming' context, which also includes the 'policy' to produce
  6655 a fully qualified name and external accesses of a fully qualified
  6656 name; NameSpace.extend is superceded by context dependent
  6657 Sign.declare_name.  Several theory and proof context operations modify
  6658 the naming context.  Especially note Theory.restore_naming and
  6659 ProofContext.restore_naming to get back to a sane state; note that
  6660 Theory.add_path is no longer sufficient to recover from
  6661 Theory.absolute_path in particular.
  6662 
  6663 * Pure: new flags short_names (default false) and unique_names
  6664 (default true) for controlling output of qualified names.  If
  6665 short_names is set, names are printed unqualified.  If unique_names is
  6666 reset, the name prefix is reduced to the minimum required to achieve
  6667 the original result when interning again, even if there is an overlap
  6668 with earlier declarations.
  6669 
  6670 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6671 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6672 (useful for printing error messages).  INCOMPATIBILITY.
  6673 
  6674 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6675 Theory.theory are now identified, referring to the universal
  6676 Context.theory (see Pure/context.ML).  Actual signature and theory
  6677 content is managed as theory data.  The old code and interfaces were
  6678 spread over many files and structures; the new arrangement introduces
  6679 considerable INCOMPATIBILITY to gain more clarity:
  6680 
  6681   Context -- theory management operations (name, identity, inclusion,
  6682     parents, ancestors, merge, etc.), plus generic theory data;
  6683 
  6684   Sign -- logical signature and syntax operations (declaring consts,
  6685     types, etc.), plus certify/read for common entities;
  6686 
  6687   Theory -- logical theory operations (stating axioms, definitions,
  6688     oracles), plus a copy of logical signature operations (consts,
  6689     types, etc.); also a few basic management operations (Theory.copy,
  6690     Theory.merge, etc.)
  6691 
  6692 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6693 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6694 for convenience -- they merely return the theory.
  6695 
  6696 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6697 
  6698 * Pure: the Isar proof context type is already defined early in Pure
  6699 as Context.proof (note that ProofContext.context and Proof.context are
  6700 aliases, where the latter is the preferred name).  This enables other
  6701 Isabelle components to refer to that type even before Isar is present.
  6702 
  6703 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6704 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6705 any of these kinds.  For example, Sign.intern typeK is now
  6706 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6707 Theory.hide_types.  Also note that former
  6708 Theory.hide_classes/types/consts are now
  6709 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6710 internalize their arguments!  INCOMPATIBILITY.
  6711 
  6712 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6713 datatype thmref (with constructors Name and NameSelection) instead of
  6714 plain string -- INCOMPATIBILITY;
  6715 
  6716 * Pure: cases produced by proof methods specify options, where NONE
  6717 means to remove case bindings -- INCOMPATIBILITY in
  6718 (RAW_)METHOD_CASES.
  6719 
  6720 * Pure: the following operations retrieve axioms or theorems from a
  6721 theory node or theory hierarchy, respectively:
  6722 
  6723   Theory.axioms_of: theory -> (string * term) list
  6724   Theory.all_axioms_of: theory -> (string * term) list
  6725   PureThy.thms_of: theory -> (string * thm) list
  6726   PureThy.all_thms_of: theory -> (string * thm) list
  6727 
  6728 * Pure: print_tac now outputs the goal through the trace channel.
  6729 
  6730 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6731 Reference Toplevel.debug (default false) controls detailed printing
  6732 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6733 controls execution profiling -- set to 1 for time and 2 for space
  6734 (both increase the runtime).
  6735 
  6736 * Isar session: The initial use of ROOT.ML is now always timed,
  6737 i.e. the log will show the actual process times, in contrast to the
  6738 elapsed wall-clock time that the outer shell wrapper produces.
  6739 
  6740 * Simplifier: improved handling of bound variables (nameless
  6741 representation, avoid allocating new strings).  Simprocs that invoke
  6742 the Simplifier recursively should use Simplifier.inherit_bounds to
  6743 avoid local name clashes.  Failure to do so produces warnings
  6744 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6745 for further details.
  6746 
  6747 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6748 bindings for all theorems stored within a given theory; this may help
  6749 in porting non-Isar theories to Isar ones, while keeping ML proof
  6750 scripts for the time being.
  6751 
  6752 * ML operator HTML.with_charset specifies the charset begin used for
  6753 generated HTML files.  For example:
  6754 
  6755   HTML.with_charset "utf-8" use_thy "Hebrew";
  6756   HTML.with_charset "utf-8" use_thy "Chinese";
  6757 
  6758 
  6759 *** System ***
  6760 
  6761 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6762 isabelle, isatool etc.).
  6763 
  6764 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6765 isatool doc, isatool mkdir, display_drafts etc.).
  6766 
  6767 * isatool usedir: option -f allows specification of the ML file to be
  6768 used by Isabelle; default is ROOT.ML.
  6769 
  6770 * New isatool version outputs the version identifier of the Isabelle
  6771 distribution being used.
  6772 
  6773 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6774 (containing Boolean satisfiability problems) into Isabelle/HOL
  6775 theories.
  6776 
  6777 
  6778 
  6779 New in Isabelle2004 (April 2004)
  6780 --------------------------------
  6781 
  6782 *** General ***
  6783 
  6784 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6785   Replaces linorder.ML.
  6786 
  6787 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6788   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6789   (\<a>...\<z>), are now considered normal letters, and can therefore
  6790   be used anywhere where an ASCII letter (a...zA...Z) has until
  6791   now. COMPATIBILITY: This obviously changes the parsing of some
  6792   terms, especially where a symbol has been used as a binder, say
  6793   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6794   as an identifier.  Fix it by inserting a space around former
  6795   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6796   existing theory and ML files.
  6797 
  6798 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6799 
  6800 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6801   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6802   a normal (but invisible) letter. For multiple letter subscripts repeat
  6803   \<^isub> like this: x\<^isub>1\<^isub>2.
  6804 
  6805 * Pure: There are now sub-/superscripts that can span more than one
  6806   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6807   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6808   superscript. The new control characters are not identifier parts.
  6809 
  6810 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6811   content of "..." to the latex file instead of \isacntrl... . The "..."
  6812   may consist of any printable characters excluding the end bracket >.
  6813 
  6814 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6815   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6816   declare constants "final", which prevents their being given a definition
  6817   later.  It is useful for constants whose behaviour is fixed axiomatically
  6818   rather than definitionally, such as the meta-logic connectives.
  6819 
  6820 * Pure: 'instance' now handles general arities with general sorts
  6821   (i.e. intersections of classes),
  6822 
  6823 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6824   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6825   It can be changed to alter the colors/layout of generated pages.
  6826 
  6827 
  6828 *** Isar ***
  6829 
  6830 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6831   cut_tac, subgoal_tac and thin_tac:
  6832   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6833     locales are no longer forced to write Isar proof scripts.
  6834     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6835     emulations.
  6836   - INCOMPATIBILITY: names of variables to be instantiated may no
  6837     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6838     This is consistent with the instantiation attribute "where".
  6839 
  6840 * Attributes "where" and "of":
  6841   - Now take type variables of instantiated theorem into account when reading
  6842     the instantiation string.  This fixes a bug that caused instantiated
  6843     theorems to have too special types in some circumstances.
  6844   - "where" permits explicit instantiations of type variables.
  6845 
  6846 * Calculation commands "moreover" and "also" no longer interfere with
  6847   current facts ("this"), admitting arbitrary combinations with "then"
  6848   and derived forms.
  6849 
  6850 * Locales:
  6851   - Goal statements involving the context element "includes" no longer
  6852     generate theorems with internal delta predicates (those ending on
  6853     "_axioms") in the premise.
  6854     Resolve particular premise with <locale>.intro to obtain old form.
  6855   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6856     specification and "includes" elements in goal statement.
  6857   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6858     [intro?] and [elim?] (respectively) by default.
  6859   - Experimental command for instantiation of locales in proof contexts:
  6860         instantiate <label>[<attrs>]: <loc>
  6861     Instantiates locale <loc> and adds all its theorems to the current context
  6862     taking into account their attributes.  Label and attrs are optional
  6863     modifiers, like in theorem declarations.  If present, names of
  6864     instantiated theorems are qualified with <label>, and the attributes
  6865     <attrs> are applied after any attributes these theorems might have already.
  6866       If the locale has assumptions, a chained fact of the form
  6867     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6868     are derived.  The command does not support old-style locales declared
  6869     with "locale (open)".
  6870       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6871 
  6872 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6873   (Isar) contexts.
  6874 
  6875 
  6876 *** HOL ***
  6877 
  6878 * Proof import: new image HOL4 contains the imported library from
  6879   the HOL4 system with about 2500 theorems. It is imported by
  6880   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6881   can be used like any other Isabelle image.  See
  6882   HOL/Import/HOL/README for more information.
  6883 
  6884 * Simplifier:
  6885   - Much improved handling of linear and partial orders.
  6886     Reasoners for linear and partial orders are set up for type classes
  6887     "linorder" and "order" respectively, and are added to the default simpset
  6888     as solvers.  This means that the simplifier can build transitivity chains
  6889     to solve goals from the assumptions.
  6890   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6891     of blast or auto after simplification become unnecessary because the goal
  6892     is solved by simplification already.
  6893 
  6894 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6895     all proved in axiomatic type classes for semirings, rings and fields.
  6896 
  6897 * Numerics:
  6898   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6899     now formalized using the Ring_and_Field theory mentioned above.
  6900   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6901     than before, because now they are set up once in a generic manner.
  6902   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6903     Look for the general versions in Ring_and_Field (and Power if they concern
  6904     exponentiation).
  6905 
  6906 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6907 
  6908 * Records:
  6909   - Record types are now by default printed with their type abbreviation
  6910     instead of the list of all field types. This can be configured via
  6911     the reference "print_record_type_abbr".
  6912   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6913     (not enabled by default).
  6914   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6915     EX x. x = sel r to True (not enabled by default).
  6916   - Tactic "record_split_simp_tac" to split and simplify records added.
  6917 
  6918 * 'specification' command added, allowing for definition by
  6919   specification.  There is also an 'ax_specification' command that
  6920   introduces the new constants axiomatically.
  6921 
  6922 * arith(_tac) is now able to generate counterexamples for reals as well.
  6923 
  6924 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6925 
  6926 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6927   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6928 
  6929 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6930   matrix theory to linear programming.
  6931 
  6932 * Unions and Intersections:
  6933   The latex output syntax of UN and INT has been changed
  6934   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6935   i.e. the index formulae has become a subscript.
  6936   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6937 
  6938 * Unions and Intersections over Intervals:
  6939   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6940   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6941   like in normal math, and corresponding versions for < and for intersection.
  6942 
  6943 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6944   lexicographic dictonary ordering has been added as "lexord".
  6945 
  6946 * ML: the legacy theory structures Int and List have been removed. They had
  6947   conflicted with ML Basis Library structures having the same names.
  6948 
  6949 * 'refute' command added to search for (finite) countermodels.  Only works
  6950   for a fragment of HOL.  The installation of an external SAT solver is
  6951   highly recommended.  See "HOL/Refute.thy" for details.
  6952 
  6953 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6954   formulae under an assignment of free variables to random values.
  6955   In contrast to 'refute', it can deal with inductive datatypes,
  6956   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6957   for examples.
  6958 
  6959 
  6960 *** HOLCF ***
  6961 
  6962 * Streams now come with concatenation and are part of the HOLCF image
  6963 
  6964 
  6965 
  6966 New in Isabelle2003 (May 2003)
  6967 ------------------------------
  6968 
  6969 *** General ***
  6970 
  6971 * Provers/simplifier:
  6972 
  6973   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6974     Assumptions are now subject to complete mutual simplification,
  6975     not just from left to right. The simplifier now preserves
  6976     the order of assumptions.
  6977 
  6978     Potential INCOMPATIBILITY:
  6979 
  6980     -- simp sometimes diverges where the old version did
  6981        not, e.g. invoking simp on the goal
  6982 
  6983         [| P (f x); y = x; f x = f y |] ==> Q
  6984 
  6985        now gives rise to the infinite reduction sequence
  6986 
  6987         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6988 
  6989        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6990        kind of problem.
  6991 
  6992     -- Tactics combining classical reasoner and simplification (such as auto)
  6993        are also affected by this change, because many of them rely on
  6994        simp. They may sometimes diverge as well or yield a different numbers
  6995        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6996        in case of problems. Sometimes subsequent calls to the classical
  6997        reasoner will fail because a preceeding call to the simplifier too
  6998        eagerly simplified the goal, e.g. deleted redundant premises.
  6999 
  7000   - The simplifier trace now shows the names of the applied rewrite rules
  7001 
  7002   - You can limit the number of recursive invocations of the simplifier
  7003     during conditional rewriting (where the simplifie tries to solve the
  7004     conditions before applying the rewrite rule):
  7005     ML "simp_depth_limit := n"
  7006     where n is an integer. Thus you can force termination where previously
  7007     the simplifier would diverge.
  7008 
  7009   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  7010 
  7011   - No longer aborts on failed congruence proof.  Instead, the
  7012     congruence is ignored.
  7013 
  7014 * Pure: New generic framework for extracting programs from constructive
  7015   proofs. See HOL/Extraction.thy for an example instantiation, as well
  7016   as HOL/Extraction for some case studies.
  7017 
  7018 * Pure: The main goal of the proof state is no longer shown by default, only
  7019 the subgoals. This behaviour is controlled by a new flag.
  7020    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  7021 (ML: Proof.show_main_goal).
  7022 
  7023 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  7024 rules whose conclusion matches subgoal 1:
  7025       PG menu: Isabelle/Isar -> Show me -> matching rules
  7026 The rules are ordered by how closely they match the subgoal.
  7027 In particular, rules that solve a subgoal outright are displayed first
  7028 (or rather last, the way they are printed).
  7029 (ML: ProofGeneral.print_intros())
  7030 
  7031 * Pure: New flag trace_unify_fail causes unification to print
  7032 diagnostic information (PG: in trace buffer) when it fails. This is
  7033 useful for figuring out why single step proofs like rule, erule or
  7034 assumption failed.
  7035 
  7036 * Pure: Locale specifications now produce predicate definitions
  7037 according to the body of text (covering assumptions modulo local
  7038 definitions); predicate "loc_axioms" covers newly introduced text,
  7039 while "loc" is cumulative wrt. all included locale expressions; the
  7040 latter view is presented only on export into the global theory
  7041 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  7042 on the old view without predicates;
  7043 
  7044 * Pure: predefined locales "var" and "struct" are useful for sharing
  7045 parameters (as in CASL, for example); just specify something like
  7046 ``var x + var y + struct M'' as import;
  7047 
  7048 * Pure: improved thms_containing: proper indexing of facts instead of
  7049 raw theorems; check validity of results wrt. current name space;
  7050 include local facts of proof configuration (also covers active
  7051 locales), cover fixed variables in index; may use "_" in term
  7052 specification; an optional limit for the number of printed facts may
  7053 be given (the default is 40);
  7054 
  7055 * Pure: disallow duplicate fact bindings within new-style theory files
  7056 (batch-mode only);
  7057 
  7058 * Provers: improved induct method: assumptions introduced by case
  7059 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  7060 the goal statement); "foo" still refers to all facts collectively;
  7061 
  7062 * Provers: the function blast.overloaded has been removed: all constants
  7063 are regarded as potentially overloaded, which improves robustness in exchange
  7064 for slight decrease in efficiency;
  7065 
  7066 * Provers/linorder: New generic prover for transitivity reasoning over
  7067 linear orders.  Note: this prover is not efficient!
  7068 
  7069 * Isar: preview of problems to finish 'show' now produce an error
  7070 rather than just a warning (in interactive mode);
  7071 
  7072 
  7073 *** HOL ***
  7074 
  7075 * arith(_tac)
  7076 
  7077  - Produces a counter example if it cannot prove a goal.
  7078    Note that the counter example may be spurious if the goal is not a formula
  7079    of quantifier-free linear arithmetic.
  7080    In ProofGeneral the counter example appears in the trace buffer.
  7081 
  7082  - Knows about div k and mod k where k is a numeral of type nat or int.
  7083 
  7084  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  7085    linear arithmetic fails. This takes account of quantifiers and divisibility.
  7086    Presburger arithmetic can also be called explicitly via presburger(_tac).
  7087 
  7088 * simp's arithmetic capabilities have been enhanced a bit: it now
  7089 takes ~= in premises into account (by performing a case split);
  7090 
  7091 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  7092 are distributed over a sum of terms;
  7093 
  7094 * New tactic "trans_tac" and method "trans" instantiate
  7095 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  7096 "<=", "<" and "=").
  7097 
  7098 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  7099 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  7100 
  7101 * 'typedef' command has new option "open" to suppress the set
  7102 definition;
  7103 
  7104 * functions Min and Max on finite sets have been introduced (theory
  7105 Finite_Set);
  7106 
  7107 * attribute [symmetric] now works for relations as well; it turns
  7108 (x,y) : R^-1 into (y,x) : R, and vice versa;
  7109 
  7110 * induct over a !!-quantified statement (say !!x1..xn):
  7111   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  7112 
  7113 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  7114 %x. None. Warning: empty_def now refers to the previously hidden definition
  7115 of the empty set.
  7116 
  7117 * Algebra: formalization of classical algebra.  Intended as base for
  7118 any algebraic development in Isabelle.  Currently covers group theory
  7119 (up to Sylow's theorem) and ring theory (Universal Property of
  7120 Univariate Polynomials).  Contributions welcome;
  7121 
  7122 * GroupTheory: deleted, since its material has been moved to Algebra;
  7123 
  7124 * Complex: new directory of the complex numbers with numeric constants,
  7125 nonstandard complex numbers, and some complex analysis, standard and
  7126 nonstandard (Jacques Fleuriot);
  7127 
  7128 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  7129 
  7130 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  7131 Fleuriot);
  7132 
  7133 * Real/HahnBanach: updated and adapted to locales;
  7134 
  7135 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  7136 Gray and Kramer);
  7137 
  7138 * UNITY: added the Meier-Sanders theory of progress sets;
  7139 
  7140 * MicroJava: bytecode verifier and lightweight bytecode verifier
  7141 as abstract algorithms, instantiated to the JVM;
  7142 
  7143 * Bali: Java source language formalization. Type system, operational
  7144 semantics, axiomatic semantics. Supported language features:
  7145 classes, interfaces, objects,virtual methods, static methods,
  7146 static/instance fields, arrays, access modifiers, definite
  7147 assignment, exceptions.
  7148 
  7149 
  7150 *** ZF ***
  7151 
  7152 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  7153 universe, etc.);
  7154 
  7155 * Main ZF: virtually all theories converted to new-style format;
  7156 
  7157 
  7158 *** ML ***
  7159 
  7160 * Pure: Tactic.prove provides sane interface for internal proofs;
  7161 omits the infamous "standard" operation, so this is more appropriate
  7162 than prove_goalw_cterm in many situations (e.g. in simprocs);
  7163 
  7164 * Pure: improved error reporting of simprocs;
  7165 
  7166 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  7167 up simprocs;
  7168 
  7169 
  7170 *** Document preparation ***
  7171 
  7172 * uses \par instead of \\ for line breaks in theory text. This may
  7173 shift some page breaks in large documents. To get the old behaviour
  7174 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  7175 
  7176 * minimized dependencies of isabelle.sty and isabellesym.sty on
  7177 other packages
  7178 
  7179 * \<euro> now needs package babel/greek instead of marvosym (which
  7180 broke \Rightarrow)
  7181 
  7182 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  7183 textcomp package)
  7184 
  7185 
  7186 
  7187 New in Isabelle2002 (March 2002)
  7188 --------------------------------
  7189 
  7190 *** Document preparation ***
  7191 
  7192 * greatly simplified document preparation setup, including more
  7193 graceful interpretation of isatool usedir -i/-d/-D options, and more
  7194 instructive isatool mkdir; users should basically be able to get
  7195 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  7196 users may run a separate document processing stage manually like this:
  7197 "isatool usedir -D output HOL Test && isatool document Test/output";
  7198 
  7199 * theory dependency graph may now be incorporated into documents;
  7200 isatool usedir -g true will produce session_graph.eps/.pdf for use
  7201 with \includegraphics of LaTeX;
  7202 
  7203 * proper spacing of consecutive markup elements, especially text
  7204 blocks after section headings;
  7205 
  7206 * support bold style (for single symbols only), input syntax is like
  7207 this: "\<^bold>\<alpha>" or "\<^bold>A";
  7208 
  7209 * \<bullet> is now output as bold \cdot by default, which looks much
  7210 better in printed text;
  7211 
  7212 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  7213 note that these symbols are currently unavailable in Proof General /
  7214 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  7215 
  7216 * isatool latex no longer depends on changed TEXINPUTS, instead
  7217 isatool document copies the Isabelle style files to the target
  7218 location;
  7219 
  7220 
  7221 *** Isar ***
  7222 
  7223 * Pure/Provers: improved proof by cases and induction;
  7224   - 'case' command admits impromptu naming of parameters (such as
  7225     "case (Suc n)");
  7226   - 'induct' method divinates rule instantiation from the inductive
  7227     claim; no longer requires excessive ?P bindings for proper
  7228     instantiation of cases;
  7229   - 'induct' method properly enumerates all possibilities of set/type
  7230     rules; as a consequence facts may be also passed through *type*
  7231     rules without further ado;
  7232   - 'induct' method now derives symbolic cases from the *rulified*
  7233     rule (before it used to rulify cases stemming from the internal
  7234     atomized version); this means that the context of a non-atomic
  7235     statement becomes is included in the hypothesis, avoiding the
  7236     slightly cumbersome show "PROP ?case" form;
  7237   - 'induct' may now use elim-style induction rules without chaining
  7238     facts, using ``missing'' premises from the goal state; this allows
  7239     rules stemming from inductive sets to be applied in unstructured
  7240     scripts, while still benefitting from proper handling of non-atomic
  7241     statements; NB: major inductive premises need to be put first, all
  7242     the rest of the goal is passed through the induction;
  7243   - 'induct' proper support for mutual induction involving non-atomic
  7244     rule statements (uses the new concept of simultaneous goals, see
  7245     below);
  7246   - append all possible rule selections, but only use the first
  7247     success (no backtracking);
  7248   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  7249   - undeclared rule case names default to numbers 1, 2, 3, ...;
  7250   - added 'print_induct_rules' (covered by help item in recent Proof
  7251     General versions);
  7252   - moved induct/cases attributes to Pure, methods to Provers;
  7253   - generic method setup instantiated for FOL and HOL;
  7254 
  7255 * Pure: support multiple simultaneous goal statements, for example
  7256 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  7257 meta-level mechanism, this acts as if several individual goals had
  7258 been stated separately; in particular common proof methods need to be
  7259 repeated in order to cover all claims; note that a single elimination
  7260 step is *not* sufficient to establish the two conjunctions, so this
  7261 fails:
  7262 
  7263   assume "A & B" then have A and B ..   (*".." fails*)
  7264 
  7265 better use "obtain" in situations as above; alternative refer to
  7266 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  7267 
  7268 * Pure: proper integration with ``locales''; unlike the original
  7269 version by Florian Kammller, Isar locales package high-level proof
  7270 contexts rather than raw logical ones (e.g. we admit to include
  7271 attributes everywhere); operations on locales include merge and
  7272 rename; support for implicit arguments (``structures''); simultaneous
  7273 type-inference over imports and text; see also HOL/ex/Locales.thy for
  7274 some examples;
  7275 
  7276 * Pure: the following commands have been ``localized'', supporting a
  7277 target locale specification "(in name)": 'lemma', 'theorem',
  7278 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  7279 stored both within the locale and at the theory level (exported and
  7280 qualified by the locale name);
  7281 
  7282 * Pure: theory goals may now be specified in ``long'' form, with
  7283 ad-hoc contexts consisting of arbitrary locale elements. for example
  7284 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  7285 definitions may be given, too); the result is a meta-level rule with
  7286 the context elements being discharged in the obvious way;
  7287 
  7288 * Pure: new proof command 'using' allows to augment currently used
  7289 facts after a goal statement ('using' is syntactically analogous to
  7290 'apply', but acts on the goal's facts only); this allows chained facts
  7291 to be separated into parts given before and after a claim, as in
  7292 ``from a and b have C using d and e <proof>'';
  7293 
  7294 * Pure: renamed "antecedent" case to "rule_context";
  7295 
  7296 * Pure: new 'judgment' command records explicit information about the
  7297 object-logic embedding (used by several tools internally); no longer
  7298 use hard-wired "Trueprop";
  7299 
  7300 * Pure: added 'corollary' command;
  7301 
  7302 * Pure: fixed 'token_translation' command;
  7303 
  7304 * Pure: removed obsolete 'exported' attribute;
  7305 
  7306 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  7307 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  7308 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  7309 
  7310 * Pure: method 'atomize' presents local goal premises as object-level
  7311 statements (atomic meta-level propositions); setup controlled via
  7312 rewrite rules declarations of 'atomize' attribute; example
  7313 application: 'induct' method with proper rule statements in improper
  7314 proof *scripts*;
  7315 
  7316 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  7317 now consider the syntactic context of assumptions, giving a better
  7318 chance to get type-inference of the arguments right (this is
  7319 especially important for locales);
  7320 
  7321 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  7322 mode;
  7323 
  7324 * Pure/obtain: the formal conclusion "thesis", being marked as
  7325 ``internal'', may no longer be reference directly in the text;
  7326 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  7327 situations;
  7328 
  7329 * Pure: generic 'sym' attribute which declares a rule both as pure
  7330 'elim?' and for the 'symmetric' operation;
  7331 
  7332 * Pure: marginal comments ``--'' may now occur just anywhere in the
  7333 text; the fixed correlation with particular command syntax has been
  7334 discontinued;
  7335 
  7336 * Pure: new method 'rules' is particularly well-suited for proof
  7337 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  7338 but often produces more compact proof terms with less detours;
  7339 
  7340 * Pure/Provers/classical: simplified integration with pure rule
  7341 attributes and methods; the classical "intro?/elim?/dest?"
  7342 declarations coincide with the pure ones; the "rule" method no longer
  7343 includes classically swapped intros; "intro" and "elim" methods no
  7344 longer pick rules from the context; also got rid of ML declarations
  7345 AddXIs/AddXEs/AddXDs; all of this has some potential for
  7346 INCOMPATIBILITY;
  7347 
  7348 * Provers/classical: attribute 'swapped' produces classical inversions
  7349 of introduction rules;
  7350 
  7351 * Provers/simplifier: 'simplified' attribute may refer to explicit
  7352 rules instead of full simplifier context; 'iff' attribute handles
  7353 conditional rules;
  7354 
  7355 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  7356 
  7357 * HOL: 'recdef' now fails on unfinished automated proofs, use
  7358 "(permissive)" option to recover old behavior;
  7359 
  7360 * HOL: 'inductive' no longer features separate (collective) attributes
  7361 for 'intros' (was found too confusing);
  7362 
  7363 * HOL: properly declared induction rules less_induct and
  7364 wf_induct_rule;
  7365 
  7366 
  7367 *** HOL ***
  7368 
  7369 * HOL: moved over to sane numeral syntax; the new policy is as
  7370 follows:
  7371 
  7372   - 0 and 1 are polymorphic constants, which are defined on any
  7373   numeric type (nat, int, real etc.);
  7374 
  7375   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  7376   binary representation internally;
  7377 
  7378   - type nat has special constructor Suc, and generally prefers Suc 0
  7379   over 1::nat and Suc (Suc 0) over 2::nat;
  7380 
  7381 This change may cause significant problems of INCOMPATIBILITY; here
  7382 are some hints on converting existing sources:
  7383 
  7384   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  7385   entities, so expressions involving "-" (unary or binary minus) need
  7386   to be spaced properly;
  7387 
  7388   - existing occurrences of "1" may need to be constraint "1::nat" or
  7389   even replaced by Suc 0; similar for old "2";
  7390 
  7391   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  7392 
  7393   - remove all special provisions on numerals in proofs;
  7394 
  7395 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  7396 representation (depends on bin_arith_simps in the default context);
  7397 
  7398 * HOL: symbolic syntax for x^2 (numeral 2);
  7399 
  7400 * HOL: the class of all HOL types is now called "type" rather than
  7401 "term"; INCOMPATIBILITY, need to adapt references to this type class
  7402 in axclass/classes, instance/arities, and (usually rare) occurrences
  7403 in typings (of consts etc.); internally the class is called
  7404 "HOL.type", ML programs should refer to HOLogic.typeS;
  7405 
  7406 * HOL/record package improvements:
  7407   - new derived operations "fields" to build a partial record section,
  7408     "extend" to promote a fixed record to a record scheme, and
  7409     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  7410     declared as simp by default;
  7411   - shared operations ("more", "fields", etc.) now need to be always
  7412     qualified) --- potential INCOMPATIBILITY;
  7413   - removed "make_scheme" operations (use "make" with "extend") --
  7414     INCOMPATIBILITY;
  7415   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  7416   - provides cases/induct rules for use with corresponding Isar
  7417     methods (for concrete records, record schemes, concrete more
  7418     parts, and schematic more parts -- in that order);
  7419   - internal definitions directly based on a light-weight abstract
  7420     theory of product types over typedef rather than datatype;
  7421 
  7422 * HOL: generic code generator for generating executable ML code from
  7423 specifications; specific support for HOL constructs such as inductive
  7424 datatypes and sets, as well as recursive functions; can be invoked
  7425 via 'generate_code' theory section;
  7426 
  7427 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  7428 
  7429 * HOL: consolidated and renamed several theories.  In particular:
  7430         Ord.thy has been absorbed into HOL.thy
  7431         String.thy has been absorbed into List.thy
  7432 
  7433 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  7434 (beware of argument permutation!);
  7435 
  7436 * HOL: linorder_less_split superseded by linorder_cases;
  7437 
  7438 * HOL/List: "nodups" renamed to "distinct";
  7439 
  7440 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  7441 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  7442   - Ex_def has changed, now need to use some_eq_ex
  7443 
  7444 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  7445 in this (rare) case use:
  7446 
  7447   delSWrapper "split_all_tac"
  7448   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  7449 
  7450 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  7451 MAY FAIL;
  7452 
  7453 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  7454 Isabelle's type classes, ^ on functions and relations has too general
  7455 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  7456 necessary to attach explicit type constraints;
  7457 
  7458 * HOL/Relation: the prefix name of the infix "O" has been changed from
  7459 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  7460 renamed accordingly (eg "compI" -> "rel_compI").
  7461 
  7462 * HOL: syntax translations now work properly with numerals and records
  7463 expressions;
  7464 
  7465 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  7466 of "lam" -- INCOMPATIBILITY;
  7467 
  7468 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  7469 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  7470 renamed "Product_Type.unit";
  7471 
  7472 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  7473 
  7474 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  7475 the "cases" method);
  7476 
  7477 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  7478 Florian Kammller);
  7479 
  7480 * HOL/IMP: updated and converted to new-style theory format; several
  7481 parts turned into readable document, with proper Isar proof texts and
  7482 some explanations (by Gerwin Klein);
  7483 
  7484 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  7485 
  7486 * HOL-Hyperreal is now a logic image;
  7487 
  7488 
  7489 *** HOLCF ***
  7490 
  7491 * Isar: consts/constdefs supports mixfix syntax for continuous
  7492 operations;
  7493 
  7494 * Isar: domain package adapted to new-style theory format, e.g. see
  7495 HOLCF/ex/Dnat.thy;
  7496 
  7497 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7498 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7499 lift.induct_tac, always use UU instead of Undef;
  7500 
  7501 * HOLCF/IMP: updated and converted to new-style theory;
  7502 
  7503 
  7504 *** ZF ***
  7505 
  7506 * Isar: proper integration of logic-specific tools and packages,
  7507 including theory commands '(co)inductive', '(co)datatype',
  7508 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7509 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7510 
  7511 * theory Main no longer includes AC; for the Axiom of Choice, base
  7512 your theory on Main_ZFC;
  7513 
  7514 * the integer library now covers quotients and remainders, with many
  7515 laws relating division to addition, multiplication, etc.;
  7516 
  7517 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7518 typeless version of the formalism;
  7519 
  7520 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7521 format;
  7522 
  7523 * ZF/Induct: new directory for examples of inductive definitions,
  7524 including theory Multiset for multiset orderings; converted to
  7525 new-style theory format;
  7526 
  7527 * ZF: many new theorems about lists, ordinals, etc.;
  7528 
  7529 
  7530 *** General ***
  7531 
  7532 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7533 variable proof controls level of detail: 0 = no proofs (only oracle
  7534 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7535 also ref manual for further ML interfaces;
  7536 
  7537 * Pure/axclass: removed obsolete ML interface
  7538 goal_subclass/goal_arity;
  7539 
  7540 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7541 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7542 separate tokens, so expressions involving minus need to be spaced
  7543 properly;
  7544 
  7545 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7546 rather than "infixl" or "infixr";
  7547 
  7548 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7549 sort constraint specifications in type inference; e.g. "x::_::foo"
  7550 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7551 type variable);
  7552 
  7553 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7554 control output of nested => (types); the default behavior is
  7555 "type_brackets";
  7556 
  7557 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7558 tokens into AST constants;
  7559 
  7560 * Pure/syntax: prefer later declarations of translations and print
  7561 translation functions; potential INCOMPATIBILITY: need to reverse
  7562 multiple declarations for same syntax element constant;
  7563 
  7564 * Pure/show_hyps reset by default (in accordance to existing Isar
  7565 practice);
  7566 
  7567 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7568 addSafter;
  7569 
  7570 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7571 as well;
  7572 
  7573 * system: tested support for MacOS X; should be able to get Isabelle +
  7574 Proof General to work in a plain Terminal after installing Poly/ML
  7575 (e.g. from the Isabelle distribution area) and GNU bash alone
  7576 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7577 support requires further installations, e.g. from
  7578 http://fink.sourceforge.net/);
  7579 
  7580 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7581 
  7582 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7583 of 40 MB), cf. ML_OPTIONS;
  7584 
  7585 * system: Proof General keywords specification is now part of the
  7586 Isabelle distribution (see etc/isar-keywords.el);
  7587 
  7588 * system: support for persistent Proof General sessions (refrain from
  7589 outdating all loaded theories on startup); user may create writable
  7590 logic images like this: ``isabelle -q HOL Test'';
  7591 
  7592 * system: smart selection of Isabelle process versus Isabelle
  7593 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7594 run both "isabelle" and "Isabelle" even if file names are badly
  7595 damaged (executable inspects the case of the first letter of its own
  7596 name); added separate "isabelle-process" and "isabelle-interface";
  7597 
  7598 * system: refrain from any attempt at filtering input streams; no
  7599 longer support ``8bit'' encoding of old isabelle font, instead proper
  7600 iso-latin characters may now be used; the related isatools
  7601 "symbolinput" and "nonascii" have disappeared as well;
  7602 
  7603 * system: removed old "xterm" interface (the print modes "xterm" and
  7604 "xterm_color" are still available for direct use in a suitable
  7605 terminal);
  7606 
  7607 
  7608 
  7609 New in Isabelle99-2 (February 2001)
  7610 -----------------------------------
  7611 
  7612 *** Overview of INCOMPATIBILITIES ***
  7613 
  7614 * HOL: please note that theories in the Library and elsewhere often use the
  7615 new-style (Isar) format; to refer to their theorems in an ML script you must
  7616 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  7617 
  7618 * HOL: inductive package no longer splits induction rule aggressively,
  7619 but only as far as specified by the introductions given; the old
  7620 format may be recovered via ML function complete_split_rule or attribute
  7621 'split_rule (complete)';
  7622 
  7623 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  7624 gfp_Tarski to gfp_unfold;
  7625 
  7626 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  7627 
  7628 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  7629 relation); infix "^^" has been renamed "``"; infix "``" has been
  7630 renamed "`"; "univalent" has been renamed "single_valued";
  7631 
  7632 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  7633 operation;
  7634 
  7635 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  7636 
  7637 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  7638 
  7639 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  7640 consequence, it is no longer monotonic wrt. the local goal context
  7641 (which is now passed through the inductive cases);
  7642 
  7643 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  7644 \<gg> to \<ggreater>;
  7645 
  7646 
  7647 *** Document preparation ***
  7648 
  7649 * \isabellestyle{NAME} selects version of Isabelle output (currently
  7650 available: are "it" for near math-mode best-style output, "sl" for
  7651 slanted text style, and "tt" for plain type-writer; if no
  7652 \isabellestyle command is given, output is according to slanted
  7653 type-writer);
  7654 
  7655 * support sub/super scripts (for single symbols only), input syntax is
  7656 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  7657 
  7658 * some more standard symbols; see Appendix A of the system manual for
  7659 the complete list of symbols defined in isabellesym.sty;
  7660 
  7661 * improved isabelle style files; more abstract symbol implementation
  7662 (should now use \isamath{...} and \isatext{...} in custom symbol
  7663 definitions);
  7664 
  7665 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  7666 state; Note that presentation of goal states does not conform to
  7667 actual human-readable proof documents.  Please do not include goal
  7668 states into document output unless you really know what you are doing!
  7669 
  7670 * proper indentation of antiquoted output with proportional LaTeX
  7671 fonts;
  7672 
  7673 * no_document ML operator temporarily disables LaTeX document
  7674 generation;
  7675 
  7676 * isatool unsymbolize tunes sources for plain ASCII communication;
  7677 
  7678 
  7679 *** Isar ***
  7680 
  7681 * Pure: Isar now suffers initial goal statements to contain unbound
  7682 schematic variables (this does not conform to actual readable proof
  7683 documents, due to unpredictable outcome and non-compositional proof
  7684 checking); users who know what they are doing may use schematic goals
  7685 for Prolog-style synthesis of proven results;
  7686 
  7687 * Pure: assumption method (an implicit finishing) now handles actual
  7688 rules as well;
  7689 
  7690 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  7691 initial goal, declare "that" only as Pure intro (only for single
  7692 steps); the "that" rule assumption may now be involved in implicit
  7693 finishing, thus ".." becomes a feasible for trivial obtains;
  7694 
  7695 * Pure: default proof step now includes 'intro_classes'; thus trivial
  7696 instance proofs may be performed by "..";
  7697 
  7698 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  7699 statements as well;
  7700 
  7701 * Pure: more robust selection of calculational rules;
  7702 
  7703 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  7704 rule (as well as the assumption rule);
  7705 
  7706 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  7707 lemmas, using the graph browser tool;
  7708 
  7709 * Pure: predict failure of "show" in interactive mode;
  7710 
  7711 * Pure: 'thms_containing' now takes actual terms as arguments;
  7712 
  7713 * HOL: improved method 'induct' --- now handles non-atomic goals
  7714 (potential INCOMPATIBILITY); tuned error handling;
  7715 
  7716 * HOL: cases and induct rules now provide explicit hints about the
  7717 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  7718 any remaining facts are inserted into the goal verbatim;
  7719 
  7720 * HOL: local contexts (aka cases) may now contain term bindings as
  7721 well; the 'cases' and 'induct' methods new provide a ?case binding for
  7722 the result to be shown in each case;
  7723 
  7724 * HOL: added 'recdef_tc' command;
  7725 
  7726 * isatool convert assists in eliminating legacy ML scripts;
  7727 
  7728 
  7729 *** HOL ***
  7730 
  7731 * HOL/Library: a collection of generic theories to be used together
  7732 with main HOL; the theory loader path already includes this directory
  7733 by default; the following existing theories have been moved here:
  7734 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  7735 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  7736 
  7737 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  7738 modelling and verification task performed in Isabelle/HOL +
  7739 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  7740 
  7741 * HOL/Algebra: special summation operator SUM no longer exists, it has
  7742 been replaced by setsum; infix 'assoc' now has priority 50 (like
  7743 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  7744 'domain', this makes the theory consistent with mathematical
  7745 literature;
  7746 
  7747 * HOL basics: added overloaded operations "inverse" and "divide"
  7748 (infix "/"), syntax for generic "abs" operation, generic summation
  7749 operator \<Sum>;
  7750 
  7751 * HOL/typedef: simplified package, provide more useful rules (see also
  7752 HOL/subset.thy);
  7753 
  7754 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  7755 now expressed as a proper nested rule (old-style tactic scripts may
  7756 require atomize_strip_tac to cope with non-atomic premises);
  7757 
  7758 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  7759 to "split_conv" (old name still available for compatibility);
  7760 
  7761 * HOL: improved concrete syntax for strings (e.g. allows translation
  7762 rules with string literals);
  7763 
  7764 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  7765  and Fleuriot's mechanization of analysis, including the transcendental
  7766  functions for the reals;
  7767 
  7768 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  7769 
  7770 
  7771 *** CTT ***
  7772 
  7773 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  7774 "lam" is displayed as TWO lambda-symbols
  7775 
  7776 * CTT: theory Main now available, containing everything (that is, Bool
  7777 and Arith);
  7778 
  7779 
  7780 *** General ***
  7781 
  7782 * Pure: the Simplifier has been implemented properly as a derived rule
  7783 outside of the actual kernel (at last!); the overall performance
  7784 penalty in practical applications is about 50%, while reliability of
  7785 the Isabelle inference kernel has been greatly improved;
  7786 
  7787 * print modes "brackets" and "no_brackets" control output of nested =>
  7788 (types) and ==> (props); the default behaviour is "brackets";
  7789 
  7790 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7791 as assumptions as well;
  7792 
  7793 * system: support Poly/ML 4.0;
  7794 
  7795 * system: isatool install handles KDE version 1 or 2;
  7796 
  7797 
  7798 
  7799 New in Isabelle99-1 (October 2000)
  7800 ----------------------------------
  7801 
  7802 *** Overview of INCOMPATIBILITIES ***
  7803 
  7804 * HOL: simplification of natural numbers is much changed; to partly
  7805 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7806 issue the following ML commands:
  7807 
  7808   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7809   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7810 
  7811 * HOL: simplification no longer dives into case-expressions; this is
  7812 controlled by "t.weak_case_cong" for each datatype t;
  7813 
  7814 * HOL: nat_less_induct renamed to less_induct;
  7815 
  7816 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7817 fixsome to patch .thy and .ML sources automatically;
  7818 
  7819   select_equality  -> some_equality
  7820   select_eq_Ex     -> some_eq_ex
  7821   selectI2EX       -> someI2_ex
  7822   selectI2         -> someI2
  7823   selectI          -> someI
  7824   select1_equality -> some1_equality
  7825   Eps_sym_eq       -> some_sym_eq_trivial
  7826   Eps_eq           -> some_eq_trivial
  7827 
  7828 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7829 
  7830 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7831 instead);
  7832 
  7833 * HOL: the recursion equations generated by 'recdef' are now called
  7834 f.simps instead of f.rules;
  7835 
  7836 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7837 
  7838 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7839 sometimes be needed;
  7840 
  7841 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7842 
  7843 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7844 
  7845 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7846 product is now "<*>" instead of "Times"; the lexicographic product is
  7847 now "<*lex*>" instead of "**";
  7848 
  7849 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7850 of main HOL, but was unused); better use HOL's datatype package;
  7851 
  7852 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7853 the old syntax may be recovered as follows:
  7854 
  7855   syntax (symbols)
  7856     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7857       (infixl "\\<oplus>" 100)
  7858 
  7859 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7860 
  7861 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7862 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7863 internally;
  7864 
  7865 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7866 changed from A/r to A//r;
  7867 
  7868 * ZF: new treatment of arithmetic (nat & int) may break some old
  7869 proofs;
  7870 
  7871 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7872 rulify -> rule_format, elimify -> elim_format, ...);
  7873 
  7874 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7875 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7876 should have to change intro!! to intro? only); replaced "delrule" by
  7877 "rule del";
  7878 
  7879 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7880 
  7881 * Provers: strengthened force_tac by using new first_best_tac;
  7882 
  7883 * LaTeX document preparation: several changes of isabelle.sty (see
  7884 lib/texinputs);
  7885 
  7886 
  7887 *** Document preparation ***
  7888 
  7889 * formal comments (text blocks etc.) in new-style theories may now
  7890 contain antiquotations of thm/prop/term/typ/text to be presented
  7891 according to latex print mode; concrete syntax is like this:
  7892 @{term[show_types] "f(x) = a + x"};
  7893 
  7894 * isatool mkdir provides easy setup of Isabelle session directories,
  7895 including proper document sources;
  7896 
  7897 * generated LaTeX sources are now deleted after successful run
  7898 (isatool document -c); may retain a copy somewhere else via -D option
  7899 of isatool usedir;
  7900 
  7901 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7902 style files, achieving self-contained LaTeX sources and simplifying
  7903 LaTeX debugging;
  7904 
  7905 * old-style theories now produce (crude) LaTeX output as well;
  7906 
  7907 * browser info session directories are now self-contained (may be put
  7908 on WWW server seperately); improved graphs of nested sessions; removed
  7909 graph for 'all sessions';
  7910 
  7911 * several improvements in isabelle style files; \isabellestyle{it}
  7912 produces fake math mode output; \isamarkupheader is now \section by
  7913 default; see lib/texinputs/isabelle.sty etc.;
  7914 
  7915 
  7916 *** Isar ***
  7917 
  7918 * Isar/Pure: local results and corresponding term bindings are now
  7919 subject to Hindley-Milner polymorphism (similar to ML); this
  7920 accommodates incremental type-inference very nicely;
  7921 
  7922 * Isar/Pure: new derived language element 'obtain' supports
  7923 generalized existence reasoning;
  7924 
  7925 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7926 support accumulation of results, without applying any rules yet;
  7927 useful to collect intermediate results without explicit name
  7928 references, and for use with transitivity rules with more than 2
  7929 premises;
  7930 
  7931 * Isar/Pure: scalable support for case-analysis type proofs: new
  7932 'case' language element refers to local contexts symbolically, as
  7933 produced by certain proof methods; internally, case names are attached
  7934 to theorems as "tags";
  7935 
  7936 * Isar/Pure: theory command 'hide' removes declarations from
  7937 class/type/const name spaces;
  7938 
  7939 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7940 indicate potential overloading;
  7941 
  7942 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7943 
  7944 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7945 "{a,b,c}" instead of {a,b,c};
  7946 
  7947 * Isar/Pure now provides its own version of intro/elim/dest
  7948 attributes; useful for building new logics, but beware of confusion
  7949 with the version in Provers/classical;
  7950 
  7951 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7952 case name 'antecedent';
  7953 
  7954 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7955 to the current context is now done automatically);
  7956 
  7957 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7958 for definining proof methods in ML;
  7959 
  7960 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7961 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7962 most cases, one should have to change intro!! to intro? only);
  7963 replaced "delrule" by "rule del";
  7964 
  7965 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7966 'symmetric' attribute (the latter supercedes [RS sym]);
  7967 
  7968 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7969 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7970 well (including splits);
  7971 
  7972 * Isar/Provers: Simplifier and Classical methods now support all kind
  7973 of modifiers used in the past, including 'cong', 'iff', etc.
  7974 
  7975 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7976 of Simplifier and Classical reasoner);
  7977 
  7978 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7979 now support named cases; major packages (inductive, datatype, primrec,
  7980 recdef) support case names and properly name parameters;
  7981 
  7982 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7983 monotonicity conditions are extracted to be proven at end of
  7984 calculations;
  7985 
  7986 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7987 method anyway;
  7988 
  7989 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7990 split_if split_if_asm; datatype package provides theorems foo.splits =
  7991 foo.split foo.split_asm for each datatype;
  7992 
  7993 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7994 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7995 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  7996 use "(cases (simplified))" method in proper proof texts);
  7997 
  7998 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  7999 
  8000 * Isar: names of theorems etc. may be natural numbers as well;
  8001 
  8002 * Isar: 'pr' command: optional arguments for goals_limit and
  8003 ProofContext.prems_limit; no longer prints theory contexts, but only
  8004 proof states;
  8005 
  8006 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  8007 additional print modes to be specified; e.g. "pr(latex)" will print
  8008 proof state according to the Isabelle LaTeX style;
  8009 
  8010 * Isar: improved support for emulating tactic scripts, including proof
  8011 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  8012 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  8013 (for HOL datatypes);
  8014 
  8015 * Isar: simplified (more robust) goal selection of proof methods: 1st
  8016 goal, all goals, or explicit goal specifier (tactic emulation); thus
  8017 'proof method scripts' have to be in depth-first order;
  8018 
  8019 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  8020 
  8021 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  8022 should instead use individual commands for printing items
  8023 (print_commands, print_methods etc.);
  8024 
  8025 * Isar: added 'nothing' --- the empty list of theorems;
  8026 
  8027 
  8028 *** HOL ***
  8029 
  8030 * HOL/MicroJava: formalization of a fragment of Java, together with a
  8031 corresponding virtual machine and a specification of its bytecode
  8032 verifier and a lightweight bytecode verifier, including proofs of
  8033 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  8034 Cornelia Pusch (see also the homepage of project Bali at
  8035 http://isabelle.in.tum.de/Bali/);
  8036 
  8037 * HOL/Algebra: new theory of rings and univariate polynomials, by
  8038 Clemens Ballarin;
  8039 
  8040 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  8041 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  8042 Rasmussen;
  8043 
  8044 * HOL/Lattice: fundamental concepts of lattice theory and order
  8045 structures, including duals, properties of bounds versus algebraic
  8046 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  8047 Theorem for complete lattices etc.; may also serve as a demonstration
  8048 for abstract algebraic reasoning using axiomatic type classes, and
  8049 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  8050 
  8051 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  8052 von Oheimb;
  8053 
  8054 * HOL/IMPP: extension of IMP with local variables and mutually
  8055 recursive procedures, by David von Oheimb;
  8056 
  8057 * HOL/Lambda: converted into new-style theory and document;
  8058 
  8059 * HOL/ex/Multiquote: example of multiple nested quotations and
  8060 anti-quotations -- basically a generalized version of de-Bruijn
  8061 representation; very useful in avoiding lifting of operations;
  8062 
  8063 * HOL/record: added general record equality rule to simpset; fixed
  8064 select-update simplification procedure to handle extended records as
  8065 well; admit "r" as field name;
  8066 
  8067 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  8068 other numeric types and also as the identity of groups, rings, etc.;
  8069 
  8070 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  8071 Types nat and int belong to this axclass;
  8072 
  8073 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  8074    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  8075    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  8076   two terms #m*u and #n*u are replaced by #(m+n)*u
  8077     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  8078   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  8079     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  8080 
  8081 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  8082 powerful prover for predicate logic but knows nothing of clasets; see
  8083 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  8084 
  8085 * HOL: new version of "case_tac" subsumes both boolean case split and
  8086 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  8087 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  8088 
  8089 * HOL: simplification no longer dives into case-expressions: only the
  8090 selector expression is simplified, but not the remaining arms; to
  8091 enable full simplification of case-expressions for datatype t, you may
  8092 remove t.weak_case_cong from the simpset, either globally (Delcongs
  8093 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  8094 
  8095 * HOL/recdef: the recursion equations generated by 'recdef' for
  8096 function 'f' are now called f.simps instead of f.rules; if all
  8097 termination conditions are proved automatically, these simplification
  8098 rules are added to the simpset, as in primrec; rules may be named
  8099 individually as well, resulting in a separate list of theorems for
  8100 each equation;
  8101 
  8102 * HOL/While is a new theory that provides a while-combinator. It
  8103 permits the definition of tail-recursive functions without the
  8104 provision of a termination measure. The latter is necessary once the
  8105 invariant proof rule for while is applied.
  8106 
  8107 * HOL: new (overloaded) notation for the set of elements below/above
  8108 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  8109 
  8110 * HOL: theorems impI, allI, ballI bound as "strip";
  8111 
  8112 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  8113 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  8114 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  8115 
  8116 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  8117 
  8118 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  8119 main HOL, but was unused);
  8120 
  8121 * HOL: fewer consts declared as global (e.g. have to refer to
  8122 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  8123 
  8124 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  8125 in case of overlap with user translations (e.g. judgements over
  8126 tuples); (note that the underlying logical represenation is still
  8127 bogus);
  8128 
  8129 
  8130 *** ZF ***
  8131 
  8132 * ZF: simplification automatically cancels common terms in arithmetic
  8133 expressions over nat and int;
  8134 
  8135 * ZF: new treatment of nat to minimize type-checking: all operators
  8136 coerce their operands to a natural number using the function natify,
  8137 making the algebraic laws unconditional;
  8138 
  8139 * ZF: as above, for int: operators coerce their operands to an integer
  8140 using the function intify;
  8141 
  8142 * ZF: the integer library now contains many of the usual laws for the
  8143 orderings, including $<=, and monotonicity laws for $+ and $*;
  8144 
  8145 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  8146 simplification;
  8147 
  8148 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  8149 to the simplifier and classical reasoner simultaneously;
  8150 
  8151 
  8152 *** General ***
  8153 
  8154 * Provers: blast_tac now handles actual object-logic rules as
  8155 assumptions; note that auto_tac uses blast_tac internally as well;
  8156 
  8157 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  8158 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  8159 
  8160 * Provers: delrules now handles destruct rules as well (no longer need
  8161 explicit make_elim);
  8162 
  8163 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  8164   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8165 use instead the strong form,
  8166   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8167 in HOL, FOL and ZF the function cla_make_elim will create such rules
  8168 from destruct-rules;
  8169 
  8170 * Provers: Simplifier.easy_setup provides a fast path to basic
  8171 Simplifier setup for new object-logics;
  8172 
  8173 * Pure: AST translation rules no longer require constant head on LHS;
  8174 
  8175 * Pure: improved name spaces: ambiguous output is qualified; support
  8176 for hiding of names;
  8177 
  8178 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  8179 XSYMBOL_HOME; no longer need to do manual configuration in most
  8180 situations;
  8181 
  8182 * system: compression of ML heaps images may now be controlled via -c
  8183 option of isabelle and isatool usedir (currently only observed by
  8184 Poly/ML);
  8185 
  8186 * system: isatool installfonts may handle X-Symbol fonts as well (very
  8187 useful for remote X11);
  8188 
  8189 * system: provide TAGS file for Isabelle sources;
  8190 
  8191 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  8192 order;
  8193 
  8194 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  8195 timing flag supersedes proof_timing and Toplevel.trace;
  8196 
  8197 * ML: new combinators |>> and |>>> for incremental transformations
  8198 with secondary results (e.g. certain theory extensions):
  8199 
  8200 * ML: PureThy.add_defs gets additional argument to indicate potential
  8201 overloading (usually false);
  8202 
  8203 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  8204 results;
  8205 
  8206 
  8207 
  8208 New in Isabelle99 (October 1999)
  8209 --------------------------------
  8210 
  8211 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8212 
  8213 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  8214 are no longer simplified.  (This allows the simplifier to unfold recursive
  8215 functional programs.)  To restore the old behaviour, declare
  8216 
  8217     Delcongs [if_weak_cong];
  8218 
  8219 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  8220 complement;
  8221 
  8222 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  8223 
  8224 * HOL/datatype: mutual_induct_tac no longer exists --
  8225   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  8226 
  8227 * HOL/typedef: fixed type inference for representing set; type
  8228 arguments now have to occur explicitly on the rhs as type constraints;
  8229 
  8230 * ZF: The con_defs part of an inductive definition may no longer refer
  8231 to constants declared in the same theory;
  8232 
  8233 * HOL, ZF: the function mk_cases, generated by the inductive
  8234 definition package, has lost an argument.  To simplify its result, it
  8235 uses the default simpset instead of a supplied list of theorems.
  8236 
  8237 * HOL/List: the constructors of type list are now Nil and Cons;
  8238 
  8239 * Simplifier: the type of the infix ML functions
  8240         setSSolver addSSolver setSolver addSolver
  8241 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  8242 for packaging solvers. A solver is created via
  8243         mk_solver: string -> (thm list -> int -> tactic) -> solver
  8244 where the string argument is only a comment.
  8245 
  8246 
  8247 *** Proof tools ***
  8248 
  8249 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  8250 decision procedure for linear arithmetic. Currently it is used for
  8251 types `nat', `int', and `real' in HOL (see below); it can, should and
  8252 will be instantiated for other types and logics as well.
  8253 
  8254 * The simplifier now accepts rewrite rules with flexible heads, eg
  8255      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  8256   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  8257   matching.
  8258 
  8259 
  8260 *** General ***
  8261 
  8262 * New Isabelle/Isar subsystem provides an alternative to traditional
  8263 tactical theorem proving; together with the ProofGeneral/isar user
  8264 interface it offers an interactive environment for developing human
  8265 readable proof documents (Isar == Intelligible semi-automated
  8266 reasoning); for further information see isatool doc isar-ref,
  8267 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  8268 
  8269 * improved and simplified presentation of theories: better HTML markup
  8270 (including colors), graph views in several sizes; isatool usedir now
  8271 provides a proper interface for user theories (via -P option); actual
  8272 document preparation based on (PDF)LaTeX is available as well (for
  8273 new-style theories only); see isatool doc system for more information;
  8274 
  8275 * native support for Proof General, both for classic Isabelle and
  8276 Isabelle/Isar;
  8277 
  8278 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  8279 using the graph browser tool;
  8280 
  8281 * Isabelle manuals now also available as PDF;
  8282 
  8283 * theory loader rewritten from scratch (may not be fully
  8284 bug-compatible); old loadpath variable has been replaced by show_path,
  8285 add_path, del_path, reset_path functions; new operations such as
  8286 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  8287 isatool doc ref);
  8288 
  8289 * improved isatool install: option -k creates KDE application icon,
  8290 option -p DIR installs standalone binaries;
  8291 
  8292 * added ML_PLATFORM setting (useful for cross-platform installations);
  8293 more robust handling of platform specific ML images for SML/NJ;
  8294 
  8295 * the settings environment is now statically scoped, i.e. it is never
  8296 created again in sub-processes invoked from isabelle, isatool, or
  8297 Isabelle;
  8298 
  8299 * path element specification '~~' refers to '$ISABELLE_HOME';
  8300 
  8301 * in locales, the "assumes" and "defines" parts may be omitted if
  8302 empty;
  8303 
  8304 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  8305 long arrows);
  8306 
  8307 * new print_mode "HTML";
  8308 
  8309 * new flag show_tags controls display of tags of theorems (which are
  8310 basically just comments that may be attached by some tools);
  8311 
  8312 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  8313 mode and goal output format:
  8314 
  8315 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  8316 244c244
  8317 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  8318 ---
  8319 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  8320 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  8321 181c181
  8322 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  8323 ---
  8324 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  8325 
  8326 * function bind_thms stores lists of theorems (cf. bind_thm);
  8327 
  8328 * new shorthand tactics ftac, eatac, datac, fatac;
  8329 
  8330 * qed (and friends) now accept "" as result name; in that case the
  8331 theorem is not stored, but proper checks and presentation of the
  8332 result still apply;
  8333 
  8334 * theorem database now also indexes constants "Trueprop", "all",
  8335 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  8336 
  8337 
  8338 *** HOL ***
  8339 
  8340 ** HOL arithmetic **
  8341 
  8342 * There are now decision procedures for linear arithmetic over nat and
  8343 int:
  8344 
  8345 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  8346 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  8347 are treated as atomic; subformulae not involving type `nat' or `int'
  8348 are ignored; quantified subformulae are ignored unless they are
  8349 positive universal or negative existential. The tactic has to be
  8350 invoked by hand and can be a little bit slow. In particular, the
  8351 running time is exponential in the number of occurrences of `min' and
  8352 `max', and `-' on `nat'.
  8353 
  8354 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  8355 (negated) (in)equalities among the premises and the conclusion into
  8356 account (i.e. no compound formulae) and does not know about `min' and
  8357 `max', and `-' on `nat'. It is fast and is used automatically by the
  8358 simplifier.
  8359 
  8360 NB: At the moment, these decision procedures do not cope with mixed
  8361 nat/int formulae where the two parts interact, such as `m < n ==>
  8362 int(m) < int(n)'.
  8363 
  8364 * HOL/Numeral provides a generic theory of numerals (encoded
  8365 efficiently as bit strings); setup for types nat/int/real is in place;
  8366 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  8367 int, existing theories and proof scripts may require a few additional
  8368 type constraints;
  8369 
  8370 * integer division and remainder can now be performed on constant
  8371 arguments;
  8372 
  8373 * many properties of integer multiplication, division and remainder
  8374 are now available;
  8375 
  8376 * An interface to the Stanford Validity Checker (SVC) is available through the
  8377 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  8378 are proved automatically.  SVC must be installed separately, and its results
  8379 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  8380 invocation of the underlying oracle).  For SVC see
  8381   http://verify.stanford.edu/SVC
  8382 
  8383 * IsaMakefile: the HOL-Real target now builds an actual image;
  8384 
  8385 
  8386 ** HOL misc **
  8387 
  8388 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  8389 (in Isabelle/Isar) -- by Gertrud Bauer;
  8390 
  8391 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  8392 analysis for assembly languages with subtypes;
  8393 
  8394 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  8395 -- avoids syntactic ambiguities and treats state, transition, and
  8396 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  8397 changed syntax and (many) tactics;
  8398 
  8399 * HOL/inductive: Now also handles more general introduction rules such
  8400   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  8401   theorems are now maintained within the theory (maintained via the
  8402   "mono" attribute);
  8403 
  8404 * HOL/datatype: Now also handles arbitrarily branching datatypes
  8405   (using function types) such as
  8406 
  8407   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  8408 
  8409 * HOL/record: record_simproc (part of the default simpset) takes care
  8410 of selectors applied to updated records; record_split_tac is no longer
  8411 part of the default claset; update_defs may now be removed from the
  8412 simpset in many cases; COMPATIBILITY: old behavior achieved by
  8413 
  8414   claset_ref () := claset() addSWrapper record_split_wrapper;
  8415   Delsimprocs [record_simproc]
  8416 
  8417 * HOL/typedef: fixed type inference for representing set; type
  8418 arguments now have to occur explicitly on the rhs as type constraints;
  8419 
  8420 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  8421 names rather than an ML expression;
  8422 
  8423 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  8424 supplied later.  Program schemes can be defined, such as
  8425     "While B C s = (if B s then While B C (C s) else s)"
  8426 where the well-founded relation can be chosen after B and C have been given.
  8427 
  8428 * HOL/List: the constructors of type list are now Nil and Cons;
  8429 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  8430 course, ML tools referring to List.list.op # etc. have to be adapted;
  8431 
  8432 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  8433 disabled by default; run isabelle with option -m HOL to get back to
  8434 the original Gordon/HOL-style output;
  8435 
  8436 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  8437 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  8438 
  8439 * HOL basic syntax simplified (more orthogonal): all variants of
  8440 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  8441 Eps operator is provided as well: "SOME x. P[x]";
  8442 
  8443 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  8444 
  8445 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  8446 thus available for user theories;
  8447 
  8448 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  8449 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  8450 time;
  8451 
  8452 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  8453 several times and then mp;
  8454 
  8455 
  8456 *** LK ***
  8457 
  8458 * the notation <<...>> is now available as a notation for sequences of
  8459 formulas;
  8460 
  8461 * the simplifier is now installed
  8462 
  8463 * the axiom system has been generalized (thanks to Soren Heilmann)
  8464 
  8465 * the classical reasoner now has a default rule database
  8466 
  8467 
  8468 *** ZF ***
  8469 
  8470 * new primrec section allows primitive recursive functions to be given
  8471 directly (as in HOL) over datatypes and the natural numbers;
  8472 
  8473 * new tactics induct_tac and exhaust_tac for induction (or case
  8474 analysis) over datatypes and the natural numbers;
  8475 
  8476 * the datatype declaration of type T now defines the recursor T_rec;
  8477 
  8478 * simplification automatically does freeness reasoning for datatype
  8479 constructors;
  8480 
  8481 * automatic type-inference, with AddTCs command to insert new
  8482 type-checking rules;
  8483 
  8484 * datatype introduction rules are now added as Safe Introduction rules
  8485 to the claset;
  8486 
  8487 * the syntax "if P then x else y" is now available in addition to
  8488 if(P,x,y);
  8489 
  8490 
  8491 *** Internal programming interfaces ***
  8492 
  8493 * tuned simplifier trace output; new flag debug_simp;
  8494 
  8495 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8496 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8497 
  8498 * AxClass.axclass_tac lost the theory argument;
  8499 
  8500 * tuned current_goals_markers semantics: begin / end goal avoids
  8501 printing empty lines;
  8502 
  8503 * removed prs and prs_fn hook, which was broken because it did not
  8504 include \n in its semantics, forcing writeln to add one
  8505 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8506 string -> unit if you really want to output text without newline;
  8507 
  8508 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8509 plain output, interface builders may have to enable 'isabelle_font'
  8510 mode to get Isabelle font glyphs as before;
  8511 
  8512 * refined token_translation interface; INCOMPATIBILITY: output length
  8513 now of type real instead of int;
  8514 
  8515 * theory loader actions may be traced via new ThyInfo.add_hook
  8516 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8517 your own database of information attached to *whole* theories -- as
  8518 opposed to intra-theory data slots offered via TheoryDataFun;
  8519 
  8520 * proper handling of dangling sort hypotheses (at last!);
  8521 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8522 extra sort hypotheses that can be witnessed from the type signature;
  8523 the force_strip_shyps flag is gone, any remaining shyps are simply
  8524 left in the theorem (with a warning issued by strip_shyps_warning);
  8525 
  8526 
  8527 
  8528 New in Isabelle98-1 (October 1998)
  8529 ----------------------------------
  8530 
  8531 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8532 
  8533 * several changes of automated proof tools;
  8534 
  8535 * HOL: major changes to the inductive and datatype packages, including
  8536 some minor incompatibilities of theory syntax;
  8537 
  8538 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8539 called `inj_on';
  8540 
  8541 * HOL: removed duplicate thms in Arith:
  8542   less_imp_add_less  should be replaced by  trans_less_add1
  8543   le_imp_add_le      should be replaced by  trans_le_add1
  8544 
  8545 * HOL: unary minus is now overloaded (new type constraints may be
  8546 required);
  8547 
  8548 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8549 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8550 now taken as an integer constant.
  8551 
  8552 * Pure: ML function 'theory_of' renamed to 'theory';
  8553 
  8554 
  8555 *** Proof tools ***
  8556 
  8557 * Simplifier:
  8558   1. Asm_full_simp_tac is now more aggressive.
  8559      1. It will sometimes reorient premises if that increases their power to
  8560         simplify.
  8561      2. It does no longer proceed strictly from left to right but may also
  8562         rotate premises to achieve further simplification.
  8563      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8564      old Asm_full_simp_tac in that it does not rotate premises.
  8565   2. The simplifier now knows a little bit about nat-arithmetic.
  8566 
  8567 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8568 allows for selected deletion of wrappers, by introduction of names for
  8569 wrapper functionals.  This implies that addbefore, addSbefore,
  8570 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8571 and that adding two tactics with the same name overwrites the first
  8572 one (emitting a warning).
  8573   type wrapper = (int -> tactic) -> (int -> tactic)
  8574   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8575   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8576   delWrapper, delSWrapper: claset *  string            -> claset
  8577   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8578 
  8579 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8580 semantics; addbefore now affects only the unsafe part of step_tac
  8581 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8582 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8583 by Force_tac;
  8584 
  8585 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8586 compWrapper; added safe wrapper (and access functions for it);
  8587 
  8588 * HOL/split_all_tac is now much faster and fails if there is nothing
  8589 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8590 and the names of the automatically generated variables have changed.
  8591 split_all_tac has moved within claset() from unsafe wrappers to safe
  8592 wrappers, which means that !!-bound variables are split much more
  8593 aggressively, and safe_tac and clarify_tac now split such variables.
  8594 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8595 Note: the same holds for record_split_tac, which does the job of
  8596 split_all_tac for record fields.
  8597 
  8598 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8599 permanently to the default simpset using Addsplits just like
  8600 Addsimps. They can be removed via Delsplits just like
  8601 Delsimps. Lower-case versions are also available.
  8602 
  8603 * HOL/Simplifier: The rule split_if is now part of the default
  8604 simpset. This means that the simplifier will eliminate all occurrences
  8605 of if-then-else in the conclusion of a goal. To prevent this, you can
  8606 either remove split_if completely from the default simpset by
  8607 `Delsplits [split_if]' or remove it in a specific call of the
  8608 simplifier using `... delsplits [split_if]'.  You can also add/delete
  8609 other case splitting rules to/from the default simpset: every datatype
  8610 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  8611 t is the name of the datatype).
  8612 
  8613 * Classical reasoner / Simplifier combination: new force_tac (and
  8614 derivatives Force_tac, force) combines rewriting and classical
  8615 reasoning (and whatever other tools) similarly to auto_tac, but is
  8616 aimed to solve the given subgoal completely.
  8617 
  8618 
  8619 *** General ***
  8620 
  8621 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  8622 and `goalw': the theory is no longer needed as an explicit argument -
  8623 the current theory context is used; assumptions are no longer returned
  8624 at the ML-level unless one of them starts with ==> or !!; it is
  8625 recommended to convert to these new commands using isatool fixgoal
  8626 (backup your sources first!);
  8627 
  8628 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  8629 the current theory context, and 'theory' to lookup stored theories;
  8630 
  8631 * new theory section 'locale' for declaring constants, assumptions and
  8632 definitions that have local scope;
  8633 
  8634 * new theory section 'nonterminals' for purely syntactic types;
  8635 
  8636 * new theory section 'setup' for generic ML setup functions
  8637 (e.g. package initialization);
  8638 
  8639 * the distribution now includes Isabelle icons: see
  8640 lib/logo/isabelle-{small,tiny}.xpm;
  8641 
  8642 * isatool install - install binaries with absolute references to
  8643 ISABELLE_HOME/bin;
  8644 
  8645 * isatool logo -- create instances of the Isabelle logo (as EPS);
  8646 
  8647 * print mode 'emacs' reserved for Isamode;
  8648 
  8649 * support multiple print (ast) translations per constant name;
  8650 
  8651 * theorems involving oracles are now printed with a suffixed [!];
  8652 
  8653 
  8654 *** HOL ***
  8655 
  8656 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  8657 
  8658 * HOL/inductive package reorganized and improved: now supports mutual
  8659 definitions such as
  8660 
  8661   inductive EVEN ODD
  8662     intrs
  8663       null "0 : EVEN"
  8664       oddI "n : EVEN ==> Suc n : ODD"
  8665       evenI "n : ODD ==> Suc n : EVEN"
  8666 
  8667 new theorem list "elims" contains an elimination rule for each of the
  8668 recursive sets; inductive definitions now handle disjunctive premises
  8669 correctly (also ZF);
  8670 
  8671 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  8672 "mutual_induct" no longer exists - the induction rule is always
  8673 contained in "induct";
  8674 
  8675 
  8676 * HOL/datatype package re-implemented and greatly improved: now
  8677 supports mutually recursive datatypes such as
  8678 
  8679   datatype
  8680     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  8681             | SUM ('a aexp) ('a aexp)
  8682             | DIFF ('a aexp) ('a aexp)
  8683             | NUM 'a
  8684   and
  8685     'a bexp = LESS ('a aexp) ('a aexp)
  8686             | AND ('a bexp) ('a bexp)
  8687             | OR ('a bexp) ('a bexp)
  8688 
  8689 as well as indirectly recursive datatypes such as
  8690 
  8691   datatype
  8692     ('a, 'b) term = Var 'a
  8693                   | App 'b ((('a, 'b) term) list)
  8694 
  8695 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  8696 induction on mutually / indirectly recursive datatypes.
  8697 
  8698 Primrec equations are now stored in theory and can be accessed via
  8699 <function_name>.simps.
  8700 
  8701 INCOMPATIBILITIES:
  8702 
  8703   - Theories using datatypes must now have theory Datatype as an
  8704     ancestor.
  8705   - The specific <typename>.induct_tac no longer exists - use the
  8706     generic induct_tac instead.
  8707   - natE has been renamed to nat.exhaust - use exhaust_tac
  8708     instead of res_inst_tac ... natE. Note that the variable
  8709     names in nat.exhaust differ from the names in natE, this
  8710     may cause some "fragile" proofs to fail.
  8711   - The theorems split_<typename>_case and split_<typename>_case_asm
  8712     have been renamed to <typename>.split and <typename>.split_asm.
  8713   - Since default sorts of type variables are now handled correctly,
  8714     some datatype definitions may have to be annotated with explicit
  8715     sort constraints.
  8716   - Primrec definitions no longer require function name and type
  8717     of recursive argument.
  8718 
  8719 Consider using isatool fixdatatype to adapt your theories and proof
  8720 scripts to the new package (backup your sources first!).
  8721 
  8722 
  8723 * HOL/record package: considerably improved implementation; now
  8724 includes concrete syntax for record types, terms, updates; theorems
  8725 for surjective pairing and splitting !!-bound record variables; proof
  8726 support is as follows:
  8727 
  8728   1) standard conversions (selectors or updates applied to record
  8729 constructor terms) are part of the standard simpset;
  8730 
  8731   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  8732 made part of standard simpset and claset via addIffs;
  8733 
  8734   3) a tactic for record field splitting (record_split_tac) is part of
  8735 the standard claset (addSWrapper);
  8736 
  8737 To get a better idea about these rules you may retrieve them via
  8738 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  8739 the name of your record type.
  8740 
  8741 The split tactic 3) conceptually simplifies by the following rule:
  8742 
  8743   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  8744 
  8745 Thus any record variable that is bound by meta-all will automatically
  8746 blow up into some record constructor term, consequently the
  8747 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  8748 solve record problems automatically.
  8749 
  8750 
  8751 * reorganized the main HOL image: HOL/Integ and String loaded by
  8752 default; theory Main includes everything;
  8753 
  8754 * automatic simplification of integer sums and comparisons, using cancellation;
  8755 
  8756 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  8757 
  8758 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  8759 
  8760 * many new identities for unions, intersections, set difference, etc.;
  8761 
  8762 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  8763 called split_if, split_split, split_sum_case and split_nat_case (to go
  8764 with add/delsplits);
  8765 
  8766 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  8767 (?x::unit) = (); this is made part of the default simpset, which COULD
  8768 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  8769 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  8770 unit_abs_eta_conv is added in order to counter the effect of
  8771 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  8772 %u.f();
  8773 
  8774 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  8775 makes more sense);
  8776 
  8777 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8778   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8779   disjointness reasoning but breaking a few old proofs.
  8780 
  8781 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  8782 to 'converse' from 'inverse' (for compatibility with ZF and some
  8783 literature);
  8784 
  8785 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  8786 the well-founded relation;
  8787 
  8788 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8789     Compl A.  The "Compl" syntax remains available as input syntax for this
  8790     release ONLY.
  8791 
  8792 * HOL/Update: new theory of function updates:
  8793     f(a:=b) == %x. if x=a then b else f x
  8794 may also be iterated as in f(a:=b,c:=d,...);
  8795 
  8796 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8797 
  8798 * HOL/List:
  8799   - new function list_update written xs[i:=v] that updates the i-th
  8800     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8801   - new function `upt' written [i..j(] which generates the list
  8802     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8803     bound write [i..j], which is a shorthand for [i..j+1(].
  8804   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8805 
  8806 * HOL/Arith:
  8807   - removed 'pred' (predecessor) function;
  8808   - generalized some theorems about n-1;
  8809   - many new laws about "div" and "mod";
  8810   - new laws about greatest common divisors (see theory ex/Primes);
  8811 
  8812 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8813 instead of "inverse";
  8814 
  8815 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8816   of the multiset ordering;
  8817 
  8818 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8819   (not included by default);
  8820 
  8821 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8822 
  8823 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8824   programs, i.e. different program variables may have different types.
  8825 
  8826 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8827   [previously, this check worked only if the rewrite rule was unconditional]
  8828   Now rew can involve either definitions or equalities (either == or =).
  8829 
  8830 
  8831 *** ZF ***
  8832 
  8833 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8834   only the theorems proved on ZF.ML;
  8835 
  8836 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8837   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8838   disjointness reasoning but breaking a few old proofs.
  8839 
  8840 * ZF/Update: new theory of function updates
  8841     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8842   may also be iterated as in f(a:=b,c:=d,...);
  8843 
  8844 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8845 
  8846 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8847   [previously, this check worked only if the rewrite rule was unconditional]
  8848   Now rew can involve either definitions or equalities (either == or =).
  8849 
  8850 * case_tac provided for compatibility with HOL
  8851     (like the old excluded_middle_tac, but with subgoals swapped)
  8852 
  8853 
  8854 *** Internal programming interfaces ***
  8855 
  8856 * Pure: several new basic modules made available for general use, see
  8857 also src/Pure/README;
  8858 
  8859 * improved the theory data mechanism to support encapsulation (data
  8860 kind name replaced by private Object.kind, acting as authorization
  8861 key); new type-safe user interface via functor TheoryDataFun; generic
  8862 print_data function becomes basically useless;
  8863 
  8864 * removed global_names compatibility flag -- all theory declarations
  8865 are qualified by default;
  8866 
  8867 * module Pure/Syntax now offers quote / antiquote translation
  8868 functions (useful for Hoare logic etc. with implicit dependencies);
  8869 see HOL/ex/Antiquote for an example use;
  8870 
  8871 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8872 cterm -> thm;
  8873 
  8874 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8875 subgoal;
  8876 
  8877 * Display.print_goals function moved to Locale.print_goals;
  8878 
  8879 * standard print function for goals supports current_goals_markers
  8880 variable for marking begin of proof, end of proof, start of goal; the
  8881 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8882 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8883 for example;
  8884 
  8885 
  8886 
  8887 New in Isabelle98 (January 1998)
  8888 --------------------------------
  8889 
  8890 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8891 
  8892 * changed lexical syntax of terms / types: dots made part of long
  8893 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8894 
  8895 * simpset (and claset) reference variable replaced by functions
  8896 simpset / simpset_ref;
  8897 
  8898 * no longer supports theory aliases (via merge) and non-trivial
  8899 implicit merge of thms' signatures;
  8900 
  8901 * most internal names of constants changed due to qualified names;
  8902 
  8903 * changed Pure/Sequence interface (see Pure/seq.ML);
  8904 
  8905 
  8906 *** General Changes ***
  8907 
  8908 * hierachically structured name spaces (for consts, types, axms, thms
  8909 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8910 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8911 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8912 long_names for fully qualified output names; NOTE: ML programs
  8913 (special tactics, packages etc.) referring to internal names may have
  8914 to be adapted to cope with fully qualified names; in case of severe
  8915 backward campatibility problems try setting 'global_names' at compile
  8916 time to have enrything declared within a flat name space; one may also
  8917 fine tune name declarations in theories via the 'global' and 'local'
  8918 section;
  8919 
  8920 * reimplemented the implicit simpset and claset using the new anytype
  8921 data filed in signatures; references simpset:simpset ref etc. are
  8922 replaced by functions simpset:unit->simpset and
  8923 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8924 to patch your ML files accordingly;
  8925 
  8926 * HTML output now includes theory graph data for display with Java
  8927 applet or isatool browser; data generated automatically via isatool
  8928 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8929 
  8930 * defs may now be conditional; improved rewrite_goals_tac to handle
  8931 conditional equations;
  8932 
  8933 * defs now admits additional type arguments, using TYPE('a) syntax;
  8934 
  8935 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8936 creates a new theory node; implicit merge of thms' signatures is
  8937 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8938 transfer:theory->thm->thm in (rare) cases;
  8939 
  8940 * improved handling of draft signatures / theories; draft thms (and
  8941 ctyps, cterms) are automatically promoted to real ones;
  8942 
  8943 * slightly changed interfaces for oracles: admit many per theory, named
  8944 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8945 
  8946 * print_goals: optional output of const types (set show_consts and
  8947 show_types);
  8948 
  8949 * improved output of warnings (###) and errors (***);
  8950 
  8951 * subgoal_tac displays a warning if the new subgoal has type variables;
  8952 
  8953 * removed old README and Makefiles;
  8954 
  8955 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8956 
  8957 * removed obsolete init_pps and init_database;
  8958 
  8959 * deleted the obsolete tactical STATE, which was declared by
  8960     fun STATE tacfun st = tacfun st st;
  8961 
  8962 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8963 (which abbreviates $HOME);
  8964 
  8965 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8966 use isatool fixseq to adapt your ML programs (this works for fully
  8967 qualified references to the Sequence structure only!);
  8968 
  8969 * use_thy no longer requires writable current directory; it always
  8970 reloads .ML *and* .thy file, if either one is out of date;
  8971 
  8972 
  8973 *** Classical Reasoner ***
  8974 
  8975 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8976 tactics that use classical reasoning to simplify a subgoal without
  8977 splitting it into several subgoals;
  8978 
  8979 * Safe_tac: like safe_tac but uses the default claset;
  8980 
  8981 
  8982 *** Simplifier ***
  8983 
  8984 * added simplification meta rules:
  8985     (asm_)(full_)simplify: simpset -> thm -> thm;
  8986 
  8987 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8988 logics (again);
  8989 
  8990 * added prems argument to simplification procedures;
  8991 
  8992 * HOL, FOL, ZF: added infix function `addsplits':
  8993   instead of `<simpset> setloop (split_tac <thms>)'
  8994   you can simply write `<simpset> addsplits <thms>'
  8995 
  8996 
  8997 *** Syntax ***
  8998 
  8999 * TYPE('a) syntax for type reflection terms;
  9000 
  9001 * no longer handles consts with name "" -- declare as 'syntax' instead;
  9002 
  9003 * pretty printer: changed order of mixfix annotation preference (again!);
  9004 
  9005 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  9006 
  9007 
  9008 *** HOL ***
  9009 
  9010 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9011   with `addloop' of the simplifier to faciliate case splitting in premises.
  9012 
  9013 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  9014 
  9015 * HOL/Auth: new protocol proofs including some for the Internet
  9016   protocol TLS;
  9017 
  9018 * HOL/Map: new theory of `maps' a la VDM;
  9019 
  9020 * HOL/simplifier: simplification procedures nat_cancel_sums for
  9021 cancelling out common nat summands from =, <, <= (in)equalities, or
  9022 differences; simplification procedures nat_cancel_factor for
  9023 cancelling common factor from =, <, <= (in)equalities over natural
  9024 sums; nat_cancel contains both kinds of procedures, it is installed by
  9025 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  9026 
  9027 * HOL/simplifier: terms of the form
  9028   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  9029   are rewritten to
  9030   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  9031   and those of the form
  9032   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  9033   are rewritten to
  9034   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  9035 
  9036 * HOL/datatype
  9037   Each datatype `t' now comes with a theorem `split_t_case' of the form
  9038 
  9039   P(t_case f1 ... fn x) =
  9040      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  9041         ...
  9042        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  9043      )
  9044 
  9045   and a theorem `split_t_case_asm' of the form
  9046 
  9047   P(t_case f1 ... fn x) =
  9048     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  9049         ...
  9050        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  9051      )
  9052   which can be added to a simpset via `addsplits'. The existing theorems
  9053   expand_list_case and expand_option_case have been renamed to
  9054   split_list_case and split_option_case.
  9055 
  9056 * HOL/Arithmetic:
  9057   - `pred n' is automatically converted to `n-1'.
  9058     Users are strongly encouraged not to use `pred' any longer,
  9059     because it will disappear altogether at some point.
  9060   - Users are strongly encouraged to write "0 < n" rather than
  9061     "n ~= 0". Theorems and proof tools have been modified towards this
  9062     `standard'.
  9063 
  9064 * HOL/Lists:
  9065   the function "set_of_list" has been renamed "set" (and its theorems too);
  9066   the function "nth" now takes its arguments in the reverse order and
  9067   has acquired the infix notation "!" as in "xs!n".
  9068 
  9069 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  9070 
  9071 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  9072   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  9073 
  9074 * HOL/record: extensible records with schematic structural subtyping
  9075 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  9076 still lacks various theorems and concrete record syntax;
  9077 
  9078 
  9079 *** HOLCF ***
  9080 
  9081 * removed "axioms" and "generated by" sections;
  9082 
  9083 * replaced "ops" section by extended "consts" section, which is capable of
  9084   handling the continuous function space "->" directly;
  9085 
  9086 * domain package:
  9087   . proves theorems immediately and stores them in the theory,
  9088   . creates hierachical name space,
  9089   . now uses normal mixfix annotations (instead of cinfix...),
  9090   . minor changes to some names and values (for consistency),
  9091   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  9092   . separator between mutual domain defs: changed "," to "and",
  9093   . improved handling of sort constraints;  now they have to
  9094     appear on the left-hand side of the equations only;
  9095 
  9096 * fixed LAM <x,y,zs>.b syntax;
  9097 
  9098 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  9099 adm (%x. P (t x)), where P is chainfinite and t continuous;
  9100 
  9101 
  9102 *** FOL and ZF ***
  9103 
  9104 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9105   with `addloop' of the simplifier to faciliate case splitting in premises.
  9106 
  9107 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  9108 in HOL, they strip ALL and --> from proved theorems;
  9109 
  9110 
  9111 
  9112 New in Isabelle94-8 (May 1997)
  9113 ------------------------------
  9114 
  9115 *** General Changes ***
  9116 
  9117 * new utilities to build / run / maintain Isabelle etc. (in parts
  9118 still somewhat experimental); old Makefiles etc. still functional;
  9119 
  9120 * new 'Isabelle System Manual';
  9121 
  9122 * INSTALL text, together with ./configure and ./build scripts;
  9123 
  9124 * reimplemented type inference for greater efficiency, better error
  9125 messages and clean internal interface;
  9126 
  9127 * prlim command for dealing with lots of subgoals (an easier way of
  9128 setting goals_limit);
  9129 
  9130 
  9131 *** Syntax ***
  9132 
  9133 * supports alternative (named) syntax tables (parser and pretty
  9134 printer); internal interface is provided by add_modesyntax(_i);
  9135 
  9136 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  9137 be used in conjunction with the Isabelle symbol font; uses the
  9138 "symbols" syntax table;
  9139 
  9140 * added token_translation interface (may translate name tokens in
  9141 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  9142 the current print_mode); IMPORTANT: user print translation functions
  9143 are responsible for marking newly introduced bounds
  9144 (Syntax.mark_boundT);
  9145 
  9146 * token translations for modes "xterm" and "xterm_color" that display
  9147 names in bold, underline etc. or colors (which requires a color
  9148 version of xterm);
  9149 
  9150 * infixes may now be declared with names independent of their syntax;
  9151 
  9152 * added typed_print_translation (like print_translation, but may
  9153 access type of constant);
  9154 
  9155 
  9156 *** Classical Reasoner ***
  9157 
  9158 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  9159 some limitations.  Blast_tac...
  9160   + ignores addss, addbefore, addafter; this restriction is intrinsic
  9161   + ignores elimination rules that don't have the correct format
  9162         (the conclusion MUST be a formula variable)
  9163   + ignores types, which can make HOL proofs fail
  9164   + rules must not require higher-order unification, e.g. apply_type in ZF
  9165     [message "Function Var's argument not a bound variable" relates to this]
  9166   + its proof strategy is more general but can actually be slower
  9167 
  9168 * substitution with equality assumptions no longer permutes other
  9169 assumptions;
  9170 
  9171 * minor changes in semantics of addafter (now called addaltern); renamed
  9172 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  9173 (and access functions for it);
  9174 
  9175 * improved combination of classical reasoner and simplifier:
  9176   + functions for handling clasimpsets
  9177   + improvement of addss: now the simplifier is called _after_ the
  9178     safe steps.
  9179   + safe variant of addss called addSss: uses safe simplifications
  9180     _during_ the safe steps. It is more complete as it allows multiple
  9181     instantiations of unknowns (e.g. with slow_tac).
  9182 
  9183 *** Simplifier ***
  9184 
  9185 * added interface for simplification procedures (functions that
  9186 produce *proven* rewrite rules on the fly, depending on current
  9187 redex);
  9188 
  9189 * ordering on terms as parameter (used for ordered rewriting);
  9190 
  9191 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  9192 
  9193 * the solver is now split into a safe and an unsafe part.
  9194 This should be invisible for the normal user, except that the
  9195 functions setsolver and addsolver have been renamed to setSolver and
  9196 addSolver; added safe_asm_full_simp_tac;
  9197 
  9198 
  9199 *** HOL ***
  9200 
  9201 * a generic induction tactic `induct_tac' which works for all datatypes and
  9202 also for type `nat';
  9203 
  9204 * a generic case distinction tactic `exhaust_tac' which works for all
  9205 datatypes and also for type `nat';
  9206 
  9207 * each datatype comes with a function `size';
  9208 
  9209 * patterns in case expressions allow tuple patterns as arguments to
  9210 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  9211 
  9212 * primrec now also works with type nat;
  9213 
  9214 * recdef: a new declaration form, allows general recursive functions to be
  9215 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  9216 
  9217 * the constant for negation has been renamed from "not" to "Not" to
  9218 harmonize with FOL, ZF, LK, etc.;
  9219 
  9220 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  9221 infinite lists;
  9222 
  9223 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  9224 
  9225 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  9226 problems in commutative rings, using axiomatic type classes for + and *;
  9227 
  9228 * more examples in HOL/MiniML and HOL/Auth;
  9229 
  9230 * more default rewrite rules for quantifiers, union/intersection;
  9231 
  9232 * a new constant `arbitrary == @x.False';
  9233 
  9234 * HOLCF/IOA replaces old HOL/IOA;
  9235 
  9236 * HOLCF changes: derived all rules and arities
  9237   + axiomatic type classes instead of classes
  9238   + typedef instead of faking type definitions
  9239   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  9240   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  9241   + eliminated the types void, one, tr
  9242   + use unit lift and bool lift (with translations) instead of one and tr
  9243   + eliminated blift from Lift3.thy (use Def instead of blift)
  9244   all eliminated rules are derived as theorems --> no visible changes ;
  9245 
  9246 
  9247 *** ZF ***
  9248 
  9249 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  9250 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  9251 as ZF_cs addSIs [equalityI];
  9252 
  9253 
  9254 
  9255 New in Isabelle94-7 (November 96)
  9256 ---------------------------------
  9257 
  9258 * allowing negative levels (as offsets) in prlev and choplev;
  9259 
  9260 * super-linear speedup for large simplifications;
  9261 
  9262 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  9263 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  9264 FAIL); can suppress it using the command Delsimps (ex_simps @
  9265 all_simps); De Morgan laws are also now included, by default;
  9266 
  9267 * improved printing of ==>  :  ~:
  9268 
  9269 * new object-logic "Sequents" adds linear logic, while replacing LK
  9270 and Modal (thanks to Sara Kalvala);
  9271 
  9272 * HOL/Auth: correctness proofs for authentication protocols;
  9273 
  9274 * HOL: new auto_tac combines rewriting and classical reasoning (many
  9275 examples on HOL/Auth);
  9276 
  9277 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  9278 the rewriter and classical reasoner simultaneously;
  9279 
  9280 * function uresult no longer returns theorems in "standard" format;
  9281 regain previous version by: val uresult = standard o uresult;
  9282 
  9283 
  9284 
  9285 New in Isabelle94-6
  9286 -------------------
  9287 
  9288 * oracles -- these establish an interface between Isabelle and trusted
  9289 external reasoners, which may deliver results as theorems;
  9290 
  9291 * proof objects (in particular record all uses of oracles);
  9292 
  9293 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  9294 
  9295 * "constdefs" section in theory files;
  9296 
  9297 * "primrec" section (HOL) no longer requires names;
  9298 
  9299 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  9300 
  9301 
  9302 
  9303 New in Isabelle94-5
  9304 -------------------
  9305 
  9306 * reduced space requirements;
  9307 
  9308 * automatic HTML generation from theories;
  9309 
  9310 * theory files no longer require "..." (quotes) around most types;
  9311 
  9312 * new examples, including two proofs of the Church-Rosser theorem;
  9313 
  9314 * non-curried (1994) version of HOL is no longer distributed;
  9315 
  9316 
  9317 
  9318 New in Isabelle94-4
  9319 -------------------
  9320 
  9321 * greatly reduced space requirements;
  9322 
  9323 * theory files (.thy) no longer require \...\ escapes at line breaks;
  9324 
  9325 * searchable theorem database (see the section "Retrieving theorems" on
  9326 page 8 of the Reference Manual);
  9327 
  9328 * new examples, including Grabczewski's monumental case study of the
  9329 Axiom of Choice;
  9330 
  9331 * The previous version of HOL renamed to Old_HOL;
  9332 
  9333 * The new version of HOL (previously called CHOL) uses a curried syntax
  9334 for functions.  Application looks like f a b instead of f(a,b);
  9335 
  9336 * Mutually recursive inductive definitions finally work in HOL;
  9337 
  9338 * In ZF, pattern-matching on tuples is now available in all abstractions and
  9339 translates to the operator "split";
  9340 
  9341 
  9342 
  9343 New in Isabelle94-3
  9344 -------------------
  9345 
  9346 * new infix operator, addss, allowing the classical reasoner to
  9347 perform simplification at each step of its search.  Example:
  9348         fast_tac (cs addss ss)
  9349 
  9350 * a new logic, CHOL, the same as HOL, but with a curried syntax
  9351 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  9352 look like (a,b) instead of <a,b>;
  9353 
  9354 * PLEASE NOTE: CHOL will eventually replace HOL!
  9355 
  9356 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  9357 It translates to the operator "split".  A new theory of integers is available;
  9358 
  9359 * In ZF, integer numerals now denote two's-complement binary integers.
  9360 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  9361 
  9362 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  9363 of the Axiom of Choice;
  9364 
  9365 
  9366 
  9367 New in Isabelle94-2
  9368 -------------------
  9369 
  9370 * Significantly faster resolution;
  9371 
  9372 * the different sections in a .thy file can now be mixed and repeated
  9373 freely;
  9374 
  9375 * Database of theorems for FOL, HOL and ZF.  New
  9376 commands including qed, qed_goal and bind_thm store theorems in the database.
  9377 
  9378 * Simple database queries: return a named theorem (get_thm) or all theorems of
  9379 a given theory (thms_of), or find out what theory a theorem was proved in
  9380 (theory_of_thm);
  9381 
  9382 * Bugs fixed in the inductive definition and datatype packages;
  9383 
  9384 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  9385 and HOL_dup_cs obsolete;
  9386 
  9387 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  9388 have been removed;
  9389 
  9390 * Simpler definition of function space in ZF;
  9391 
  9392 * new results about cardinal and ordinal arithmetic in ZF;
  9393 
  9394 * 'subtype' facility in HOL for introducing new types as subsets of existing
  9395 types;
  9396 
  9397 :mode=text:wrap=hard:maxLineLen=72: