NEWS
author wenzelm
Sat, 14 Apr 2012 12:51:38 +0200
changeset 48334 9be52539082d
parent 48333 8f85051693d1
child 48335 b1cd02f2d534
permissions -rw-r--r--
revert changes of already published NEWS;
     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 * ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
    51 (not just JRE).
    52 
    53 
    54 *** Pure ***
    55 
    56 * Rule composition via attribute "OF" (or ML functions OF/MRS) is more
    57 tolerant against multiple unifiers, as long as the final result is
    58 unique.  (As before, rules are composed in canonical right-to-left
    59 order to accommodate newly introduced premises.)
    60 
    61 * Command 'definition' no longer exports the foundational "raw_def"
    62 into the user context.  Minor INCOMPATIBILITY, may use the regular
    63 "def" result with attribute "abs_def" to imitate the old version.
    64 
    65 * Attribute "abs_def" turns an equation of the form "f x y == t" into
    66 "f == %x y. t", which ensures that "simp" or "unfold" steps always
    67 expand it.  This also works for object-logic equality.  (Formerly
    68 undocumented feature.)
    69 
    70 * Discontinued old "prems" fact, which used to refer to the accidental
    71 collection of foundational premises in the context (marked as legacy
    72 since Isabelle2011).
    73 
    74 * Obsolete command 'types' has been discontinued.  Use 'type_synonym'
    75 instead.  INCOMPATIBILITY.
    76 
    77 * Ancient code generator for SML and its commands 'code_module',
    78 'code_library', 'consts_code', 'types_code' have been discontinued.
    79 Use commands of the generic code generator instead.  INCOMPATIBILITY.
    80 
    81 * Redundant attribute 'code_inline' has been discontinued. Use
    82 'code_unfold' instead.  INCOMPATIBILITY.
    83 
    84 * Dropped attribute 'code_unfold_post' in favor of the its dual
    85 'code_abbrev', which yields a common pattern in definitions like
    86 
    87   definition [code_abbrev]: "f = t"
    88 
    89 INCOMPATIBILITY.
    90 
    91 * Sort constraints are now propagated in simultaneous statements, just
    92 like type constraints.  INCOMPATIBILITY in rare situations, where
    93 distinct sorts used to be assigned accidentally.  For example:
    94 
    95   lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"
    96 
    97   lemma "P (x::'a)" and "Q (y::'a::bar)"
    98     -- "now uniform 'a::bar instead of default sort for first occurrence (!)"
    99 
   100 
   101 *** HOL ***
   102 
   103 * New tutorial Programming and Proving in Isabelle/HOL
   104 
   105 * The representation of numerals has changed. We now have a datatype
   106 "num" representing strictly positive binary numerals, along with
   107 functions "numeral :: num => 'a" and "neg_numeral :: num => 'a" to
   108 represent positive and negated numeric literals, respectively. (See
   109 definitions in Num.thy.) Potential INCOMPATIBILITY; some user theories
   110 may require adaptations:
   111 
   112   - Theorems with number_ring or number_semiring constraints: These
   113     classes are gone; use comm_ring_1 or comm_semiring_1 instead.
   114 
   115   - Theories defining numeric types: Remove number, number_semiring,
   116     and number_ring instances. Defer all theorems about numerals until
   117     after classes one and semigroup_add have been instantiated.
   118 
   119   - Numeral-only simp rules: Replace each rule having a "number_of v"
   120     pattern with two copies, one for numeral and one for neg_numeral.
   121 
   122   - Theorems about subclasses of semiring_1 or ring_1: These classes
   123     automatically support numerals now, so more simp rules and
   124     simprocs may now apply within the proof.
   125 
   126   - Definitions and theorems using old constructors Pls/Min/Bit0/Bit1:
   127     Redefine using other integer operations.
   128 
   129 * Type 'a set is now a proper type constructor (just as before
   130 Isabelle2008).  Definitions mem_def and Collect_def have disappeared.
   131 Non-trivial INCOMPATIBILITY.  For developments keeping predicates and
   132 sets separate, it is often sufficient to rephrase sets S accidentally
   133 used as predicates by "%x. x : S" and predicates P accidentally used
   134 as sets by "{x. P x}".  Corresponding proofs in a first step should be
   135 pruned from any tinkering with former theorems mem_def and
   136 Collect_def as far as possible.
   137 For developments which deliberately mixed predicates and
   138 sets, a planning step is necessary to determine what should become a
   139 predicate and what a set.  It can be helpful to carry out that step in
   140 Isabelle2011-1 before jumping right into the current release.
   141 
   142 * Code generation by default implements sets as container type rather
   143 than predicates.  INCOMPATIBILITY.
   144 
   145 * New proof import from HOL Light: Faster, simpler, and more scalable.
   146 Requires a proof bundle, which is available as an external component.
   147 Removed old (and mostly dead) Importer for HOL4 and HOL Light.
   148 INCOMPATIBILITY.
   149 
   150 * New type synonym 'a rel = ('a * 'a) set
   151 
   152 * Theory Divides: Discontinued redundant theorems about div and mod.
   153 INCOMPATIBILITY, use the corresponding generic theorems instead.
   154 
   155   DIVISION_BY_ZERO ~> div_by_0, mod_by_0
   156   zdiv_self ~> div_self
   157   zmod_self ~> mod_self
   158   zdiv_zero ~> div_0
   159   zmod_zero ~> mod_0
   160   zdiv_zmod_equality ~> div_mod_equality2
   161   zdiv_zmod_equality2 ~> div_mod_equality
   162   zmod_zdiv_trivial ~> mod_div_trivial
   163   zdiv_zminus_zminus ~> div_minus_minus
   164   zmod_zminus_zminus ~> mod_minus_minus
   165   zdiv_zminus2 ~> div_minus_right
   166   zmod_zminus2 ~> mod_minus_right
   167   zdiv_minus1_right ~> div_minus1_right
   168   zmod_minus1_right ~> mod_minus1_right
   169   zdvd_mult_div_cancel ~> dvd_mult_div_cancel
   170   zmod_zmult1_eq ~> mod_mult_right_eq
   171   zpower_zmod ~> power_mod
   172   zdvd_zmod ~> dvd_mod
   173   zdvd_zmod_imp_zdvd ~> dvd_mod_imp_dvd
   174   mod_mult_distrib ~> mult_mod_left
   175   mod_mult_distrib2 ~> mult_mod_right
   176 
   177 * Removed redundant theorems nat_mult_2 and nat_mult_2_right; use
   178 generic mult_2 and mult_2_right instead. INCOMPATIBILITY.
   179 
   180 * More default pred/set conversions on a couple of relation operations
   181 and predicates.  Added powers of predicate relations.
   182 Consolidation of some relation theorems:
   183 
   184   converse_def ~> converse_unfold
   185   rel_comp_def ~> rel_comp_unfold
   186   symp_def ~> (dropped, use symp_def and sym_def instead)
   187   transp_def ~> transp_trans
   188   Domain_def ~> Domain_unfold
   189   Range_def ~> Domain_converse [symmetric]
   190 
   191 Generalized theorems INF_INT_eq, INF_INT_eq2, SUP_UN_eq, SUP_UN_eq2.
   192 
   193 See theory "Relation" for examples for making use of pred/set conversions
   194 by means of attributes "to_set" and "to_pred".
   195 
   196 INCOMPATIBILITY.
   197 
   198 * Consolidated various theorem names relating to Finite_Set.fold
   199 combinator:
   200 
   201   inf_INFI_fold_inf ~> inf_INF_fold_inf
   202   sup_SUPR_fold_sup ~> sup_SUP_fold_sup
   203   INFI_fold_inf ~> INF_fold_inf
   204   SUPR_fold_sup ~> SUP_fold_sup
   205   union_set ~> union_set_fold
   206   minus_set ~> minus_set_fold
   207 
   208 INCOMPATIBILITY.
   209 
   210 * Consolidated theorem names concerning fold combinators:
   211 
   212   INFI_set_fold ~> INF_set_fold
   213   SUPR_set_fold ~> SUP_set_fold
   214   INF_code ~> INF_set_foldr
   215   SUP_code ~> SUP_set_foldr
   216   foldr.simps ~> foldr.simps (in point-free formulation)
   217   foldr_fold_rev ~> foldr_conv_fold
   218   foldl_fold ~> foldl_conv_fold
   219   foldr_foldr ~> foldr_conv_foldl
   220   foldl_foldr ~> foldl_conv_foldr
   221 
   222 INCOMPATIBILITY.
   223 
   224 * Dropped rarely useful theorems concerning fold combinators:
   225 foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
   226 rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
   227 concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
   228 foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
   229 listsum_conv_fold, listsum_foldl, sort_foldl_insort, foldl_assoc,
   230 foldr_conv_foldl, start_le_sum, elem_le_sum, sum_eq_0_conv.
   231 INCOMPATIBILITY.  For the common phrases "%xs. List.foldr plus xs 0"
   232 and "List.foldl plus 0", prefer "List.listsum".  Otherwise it can
   233 be useful to boil down "List.foldr" and "List.foldl" to "List.fold"
   234 by unfolding "foldr_conv_fold" and "foldl_conv_fold".
   235 
   236 * Dropped lemmas minus_set_foldr, union_set_foldr, union_coset_foldr,
   237 inter_coset_foldr, Inf_fin_set_foldr, Sup_fin_set_foldr,
   238 Min_fin_set_foldr, Max_fin_set_foldr, Inf_set_foldr, Sup_set_foldr,
   239 INF_set_foldr, SUP_set_foldr.  INCOMPATIBILITY.  Prefer corresponding
   240 lemmas over fold rather than foldr, or make use of lemmas
   241 fold_conv_foldr and fold_rev.
   242 
   243 * Congruence rules Option.map_cong and Option.bind_cong for recursion
   244 through option types.
   245 
   246 * Concrete syntax for case expressions includes constraints for source
   247 positions, and thus produces Prover IDE markup for its bindings.
   248 INCOMPATIBILITY for old-style syntax translations that augment the
   249 pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of
   250 one_case.
   251 
   252 * Discontinued configuration option "syntax_positions": atomic terms
   253 in parse trees are always annotated by position constraints.
   254 
   255 * Finite_Set.fold now qualified.  INCOMPATIBILITY.
   256 
   257 * Renamed some facts on canonical fold on lists, in order to avoid
   258 problems with interpretation involving corresponding facts on foldl
   259 with the same base names:
   260 
   261   fold_set_remdups ~> fold_set_fold_remdups
   262   fold_set ~> fold_set_fold
   263   fold1_set ~> fold1_set_fold
   264 
   265 INCOMPATIBILITY.
   266 
   267 * Renamed facts about the power operation on relations, i.e., relpow
   268   to match the constant's name:
   269 
   270   rel_pow_1 ~> relpow_1
   271   rel_pow_0_I ~> relpow_0_I
   272   rel_pow_Suc_I ~> relpow_Suc_I
   273   rel_pow_Suc_I2 ~> relpow_Suc_I2
   274   rel_pow_0_E ~> relpow_0_E
   275   rel_pow_Suc_E ~> relpow_Suc_E
   276   rel_pow_E ~> relpow_E
   277   rel_pow_Suc_D2 ~> relpow_Suc_D2
   278   rel_pow_Suc_E2 ~> relpow_Suc_E2
   279   rel_pow_Suc_D2' ~> relpow_Suc_D2'
   280   rel_pow_E2 ~> relpow_E2
   281   rel_pow_add ~> relpow_add
   282   rel_pow_commute ~> relpow
   283   rel_pow_empty ~> relpow_empty:
   284   rtrancl_imp_UN_rel_pow ~> rtrancl_imp_UN_relpow
   285   rel_pow_imp_rtrancl ~> relpow_imp_rtrancl
   286   rtrancl_is_UN_rel_pow ~> rtrancl_is_UN_relpow
   287   rtrancl_imp_rel_pow ~> rtrancl_imp_relpow
   288   rel_pow_fun_conv ~> relpow_fun_conv
   289   rel_pow_finite_bounded1 ~> relpow_finite_bounded1
   290   rel_pow_finite_bounded ~> relpow_finite_bounded
   291   rtrancl_finite_eq_rel_pow ~> rtrancl_finite_eq_relpow
   292   trancl_finite_eq_rel_pow ~> trancl_finite_eq_relpow
   293   single_valued_rel_pow ~> single_valued_relpow
   294 
   295 INCOMPATIBILITY.
   296 
   297 * Theory Relation: Consolidated constant name for relation composition
   298   and corresponding theorem names:
   299   - Renamed constant rel_comp to relcomp
   300   - Dropped abbreviation pred_comp. Use relcompp instead.
   301   - Renamed theorems:
   302   Relation:
   303     rel_compI ~> relcompI
   304     rel_compEpair ~> relcompEpair
   305     rel_compE ~> relcompE
   306     pred_comp_rel_comp_eq ~> relcompp_relcomp_eq
   307     rel_comp_empty1 ~> relcomp_empty1
   308     rel_comp_mono ~> relcomp_mono
   309     rel_comp_subset_Sigma ~> relcomp_subset_Sigma
   310     rel_comp_distrib ~> relcomp_distrib
   311     rel_comp_distrib2 ~> relcomp_distrib2
   312     rel_comp_UNION_distrib ~> relcomp_UNION_distrib
   313     rel_comp_UNION_distrib2 ~> relcomp_UNION_distrib2
   314     single_valued_rel_comp ~> single_valued_relcomp
   315     rel_comp_unfold ~> relcomp_unfold
   316     converse_rel_comp ~> converse_relcomp
   317     pred_compI ~> relcomppI
   318     pred_compE ~> relcomppE
   319     pred_comp_bot1 ~> relcompp_bot1
   320     pred_comp_bot2 ~> relcompp_bot2
   321     transp_pred_comp_less_eq ~> transp_relcompp_less_eq
   322     pred_comp_mono ~> relcompp_mono
   323     pred_comp_distrib ~> relcompp_distrib
   324     pred_comp_distrib2 ~> relcompp_distrib2
   325     converse_pred_comp ~> converse_relcompp
   326   Transitive_Closure:
   327     finite_rel_comp ~> finite_relcomp
   328   List:
   329     set_rel_comp ~> set_relcomp
   330 
   331 INCOMPATIBILITY.
   332 
   333 * New theory HOL/Library/DAList provides an abstract type for association
   334   lists with distinct keys.
   335 
   336 * 'datatype' specifications allow explicit sort constraints.
   337 
   338 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
   339 use theory HOL/Library/Nat_Bijection instead.
   340 
   341 * Theory HOL/Library/RBT_Impl: Backing implementation of red-black trees is
   342 now inside the type class' local context. Names of affected operations and lemmas
   343 have been prefixed by rbt_. INCOMPATIBILITY for theories working directly with
   344 raw red-black trees, adapt the names as follows:
   345 
   346   Operations:
   347   bulkload -> rbt_bulkload
   348   del_from_left -> rbt_del_from_left
   349   del_from_right -> rbt_del_from_right
   350   del -> rbt_del
   351   delete -> rbt_delete
   352   ins -> rbt_ins
   353   insert -> rbt_insert
   354   insertw -> rbt_insert_with
   355   insert_with_key -> rbt_insert_with_key
   356   map_entry -> rbt_map_entry
   357   lookup -> rbt_lookup
   358   sorted -> rbt_sorted
   359   tree_greater -> rbt_greater
   360   tree_less -> rbt_less
   361   tree_less_symbol -> rbt_less_symbol
   362   union -> rbt_union
   363   union_with -> rbt_union_with
   364   union_with_key -> rbt_union_with_key
   365 
   366   Lemmas:
   367   balance_left_sorted -> balance_left_rbt_sorted
   368   balance_left_tree_greater -> balance_left_rbt_greater
   369   balance_left_tree_less -> balance_left_rbt_less
   370   balance_right_sorted -> balance_right_rbt_sorted
   371   balance_right_tree_greater -> balance_right_rbt_greater
   372   balance_right_tree_less -> balance_right_rbt_less
   373   balance_sorted -> balance_rbt_sorted
   374   balance_tree_greater -> balance_rbt_greater
   375   balance_tree_less -> balance_rbt_less
   376   bulkload_is_rbt -> rbt_bulkload_is_rbt
   377   combine_sorted -> combine_rbt_sorted
   378   combine_tree_greater -> combine_rbt_greater
   379   combine_tree_less -> combine_rbt_less
   380   delete_in_tree -> rbt_delete_in_tree
   381   delete_is_rbt -> rbt_delete_is_rbt
   382   del_from_left_tree_greater -> rbt_del_from_left_rbt_greater
   383   del_from_left_tree_less -> rbt_del_from_left_rbt_less
   384   del_from_right_tree_greater -> rbt_del_from_right_rbt_greater
   385   del_from_right_tree_less -> rbt_del_from_right_rbt_less
   386   del_in_tree -> rbt_del_in_tree
   387   del_inv1_inv2 -> rbt_del_inv1_inv2
   388   del_sorted -> rbt_del_rbt_sorted
   389   del_tree_greater -> rbt_del_rbt_greater
   390   del_tree_less -> rbt_del_rbt_less
   391   dom_lookup_Branch -> dom_rbt_lookup_Branch
   392   entries_lookup -> entries_rbt_lookup
   393   finite_dom_lookup -> finite_dom_rbt_lookup
   394   insert_sorted -> rbt_insert_rbt_sorted
   395   insertw_is_rbt -> rbt_insertw_is_rbt
   396   insertwk_is_rbt -> rbt_insertwk_is_rbt
   397   insertwk_sorted -> rbt_insertwk_rbt_sorted
   398   insertw_sorted -> rbt_insertw_rbt_sorted
   399   ins_sorted -> ins_rbt_sorted
   400   ins_tree_greater -> ins_rbt_greater
   401   ins_tree_less -> ins_rbt_less
   402   is_rbt_sorted -> is_rbt_rbt_sorted
   403   lookup_balance -> rbt_lookup_balance
   404   lookup_bulkload -> rbt_lookup_rbt_bulkload
   405   lookup_delete -> rbt_lookup_rbt_delete
   406   lookup_Empty -> rbt_lookup_Empty
   407   lookup_from_in_tree -> rbt_lookup_from_in_tree
   408   lookup_in_tree -> rbt_lookup_in_tree
   409   lookup_ins -> rbt_lookup_ins
   410   lookup_insert -> rbt_lookup_rbt_insert
   411   lookup_insertw -> rbt_lookup_rbt_insertw
   412   lookup_insertwk -> rbt_lookup_rbt_insertwk
   413   lookup_keys -> rbt_lookup_keys
   414   lookup_map -> rbt_lookup_map
   415   lookup_map_entry -> rbt_lookup_rbt_map_entry
   416   lookup_tree_greater -> rbt_lookup_rbt_greater
   417   lookup_tree_less -> rbt_lookup_rbt_less
   418   lookup_union -> rbt_lookup_rbt_union
   419   map_entry_color_of -> rbt_map_entry_color_of
   420   map_entry_inv1 -> rbt_map_entry_inv1
   421   map_entry_inv2 -> rbt_map_entry_inv2
   422   map_entry_is_rbt -> rbt_map_entry_is_rbt
   423   map_entry_sorted -> rbt_map_entry_rbt_sorted
   424   map_entry_tree_greater -> rbt_map_entry_rbt_greater
   425   map_entry_tree_less -> rbt_map_entry_rbt_less
   426   map_tree_greater -> map_rbt_greater
   427   map_tree_less -> map_rbt_less
   428   map_sorted -> map_rbt_sorted
   429   paint_sorted -> paint_rbt_sorted
   430   paint_lookup -> paint_rbt_lookup
   431   paint_tree_greater -> paint_rbt_greater
   432   paint_tree_less -> paint_rbt_less
   433   sorted_entries -> rbt_sorted_entries
   434   tree_greater_eq_trans -> rbt_greater_eq_trans
   435   tree_greater_nit -> rbt_greater_nit
   436   tree_greater_prop -> rbt_greater_prop
   437   tree_greater_simps -> rbt_greater_simps
   438   tree_greater_trans -> rbt_greater_trans
   439   tree_less_eq_trans -> rbt_less_eq_trans
   440   tree_less_nit -> rbt_less_nit
   441   tree_less_prop -> rbt_less_prop
   442   tree_less_simps -> rbt_less_simps
   443   tree_less_trans -> rbt_less_trans
   444   tree_ord_props -> rbt_ord_props
   445   union_Branch -> rbt_union_Branch
   446   union_is_rbt -> rbt_union_is_rbt
   447   unionw_is_rbt -> rbt_unionw_is_rbt
   448   unionwk_is_rbt -> rbt_unionwk_is_rbt
   449   unionwk_sorted -> rbt_unionwk_rbt_sorted
   450 
   451 * Session HOL-Word: Discontinued many redundant theorems specific to
   452 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
   453 instead.
   454 
   455   word_sub_alt ~> word_sub_wi
   456   word_add_alt ~> word_add_def
   457   word_mult_alt ~> word_mult_def
   458   word_minus_alt ~> word_minus_def
   459   word_0_alt ~> word_0_wi
   460   word_1_alt ~> word_1_wi
   461   word_add_0 ~> add_0_left
   462   word_add_0_right ~> add_0_right
   463   word_mult_1 ~> mult_1_left
   464   word_mult_1_right ~> mult_1_right
   465   word_add_commute ~> add_commute
   466   word_add_assoc ~> add_assoc
   467   word_add_left_commute ~> add_left_commute
   468   word_mult_commute ~> mult_commute
   469   word_mult_assoc ~> mult_assoc
   470   word_mult_left_commute ~> mult_left_commute
   471   word_left_distrib ~> left_distrib
   472   word_right_distrib ~> right_distrib
   473   word_left_minus ~> left_minus
   474   word_diff_0_right ~> diff_0_right
   475   word_diff_self ~> diff_self
   476   word_sub_def ~> diff_minus
   477   word_diff_minus ~> diff_minus
   478   word_add_ac ~> add_ac
   479   word_mult_ac ~> mult_ac
   480   word_plus_ac0 ~> add_0_left add_0_right add_ac
   481   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
   482   word_order_trans ~> order_trans
   483   word_order_refl ~> order_refl
   484   word_order_antisym ~> order_antisym
   485   word_order_linear ~> linorder_linear
   486   lenw1_zero_neq_one ~> zero_neq_one
   487   word_number_of_eq ~> number_of_eq
   488   word_of_int_add_hom ~> wi_hom_add
   489   word_of_int_sub_hom ~> wi_hom_sub
   490   word_of_int_mult_hom ~> wi_hom_mult
   491   word_of_int_minus_hom ~> wi_hom_neg
   492   word_of_int_succ_hom ~> wi_hom_succ
   493   word_of_int_pred_hom ~> wi_hom_pred
   494   word_of_int_0_hom ~> word_0_wi
   495   word_of_int_1_hom ~> word_1_wi
   496 
   497 * Clarified attribute "mono_set": pure declaration without modifying
   498 the result of the fact expression.
   499 
   500 * "Transitive_Closure.ntrancl": bounded transitive closure on
   501 relations.
   502 
   503 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
   504 
   505 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
   506 
   507 * Theory Int: Discontinued many legacy theorems specific to type int.
   508 INCOMPATIBILITY, use the corresponding generic theorems instead.
   509 
   510   zminus_zminus ~> minus_minus
   511   zminus_0 ~> minus_zero
   512   zminus_zadd_distrib ~> minus_add_distrib
   513   zadd_commute ~> add_commute
   514   zadd_assoc ~> add_assoc
   515   zadd_left_commute ~> add_left_commute
   516   zadd_ac ~> add_ac
   517   zmult_ac ~> mult_ac
   518   zadd_0 ~> add_0_left
   519   zadd_0_right ~> add_0_right
   520   zadd_zminus_inverse2 ~> left_minus
   521   zmult_zminus ~> mult_minus_left
   522   zmult_commute ~> mult_commute
   523   zmult_assoc ~> mult_assoc
   524   zadd_zmult_distrib ~> left_distrib
   525   zadd_zmult_distrib2 ~> right_distrib
   526   zdiff_zmult_distrib ~> left_diff_distrib
   527   zdiff_zmult_distrib2 ~> right_diff_distrib
   528   zmult_1 ~> mult_1_left
   529   zmult_1_right ~> mult_1_right
   530   zle_refl ~> order_refl
   531   zle_trans ~> order_trans
   532   zle_antisym ~> order_antisym
   533   zle_linear ~> linorder_linear
   534   zless_linear ~> linorder_less_linear
   535   zadd_left_mono ~> add_left_mono
   536   zadd_strict_right_mono ~> add_strict_right_mono
   537   zadd_zless_mono ~> add_less_le_mono
   538   int_0_less_1 ~> zero_less_one
   539   int_0_neq_1 ~> zero_neq_one
   540   zless_le ~> less_le
   541   zpower_zadd_distrib ~> power_add
   542   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   543   zero_le_zpower_abs ~> zero_le_power_abs
   544 
   545 * Theory Deriv: Renamed
   546 
   547   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   548 
   549 * New "case_product" attribute to generate a case rule doing multiple
   550 case distinctions at the same time.  E.g.
   551 
   552   list.exhaust [case_product nat.exhaust]
   553 
   554 produces a rule which can be used to perform case distinction on both
   555 a list and a nat.
   556 
   557 * Improved code generation of multisets.
   558 
   559 * New diagnostic command find_unused_assms to find potentially superfluous
   560   assumptions in theorems using Quickcheck.
   561 
   562 * Quickcheck:
   563   - Quickcheck returns variable assignments as counterexamples, which
   564     allows to reveal the underspecification of functions under test.
   565     For example, refuting "hd xs = x", it presents the variable
   566     assignment xs = [] and x = a1 as a counterexample, assuming that
   567     any property is false whenever "hd []" occurs in it.
   568     These counterexample are marked as potentially spurious, as
   569     Quickcheck also returns "xs = []" as a counterexample to the
   570     obvious theorem "hd xs = hd xs".
   571     After finding a potentially spurious counterexample, Quickcheck
   572     continues searching for genuine ones.
   573     By default, Quickcheck shows potentially spurious and genuine
   574     counterexamples. The option "genuine_only" sets quickcheck to
   575     only show genuine counterexamples.
   576 
   577   - The command 'quickcheck_generator' creates random and exhaustive
   578     value generators for a given type and operations.
   579     It generates values by using the operations as if they were
   580     constructors of that type.
   581 
   582   - Support for multisets.
   583 
   584   - Added "use_subtype" options.
   585   - Added "quickcheck_locale" configuration to specify how to process
   586     conjectures in a locale context.
   587 
   588 * Nitpick:
   589   - Fixed infinite loop caused by the 'peephole_optim' option and
   590     affecting 'rat' and 'real'.
   591 
   592 * Sledgehammer:
   593   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   594   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   595   - Renamed "sound" option to "strict".
   596 
   597 * Metis:
   598   - Added possibility to specify lambda translations scheme as a
   599     parenthesized argument (e.g., "by (metis (lifting) ...)").
   600 
   601 * SMT:
   602   - renamed "smt_fixed" option to "smt_read_only_certificates".
   603 
   604 * Command 'try0':
   605   - Renamed from 'try_methods'. INCOMPATIBILITY.
   606 
   607 * New "eventually_elim" method as a generalized variant of the
   608   eventually_elim* rules. Supports structured proofs.
   609 
   610 * HOL/TPTP: support to parse and import TPTP problems (all languages)
   611   into Isabelle/HOL.
   612 
   613 
   614 *** FOL ***
   615 
   616 * New "case_product" attribute (see HOL).
   617 
   618 
   619 *** ZF ***
   620 
   621 * Greater support for structured proofs involving induction or case
   622 analysis.
   623 
   624 * Much greater use of mathematical symbols.
   625 
   626 * Removal of many ML theorem bindings.  INCOMPATIBILITY.
   627 
   628 
   629 *** ML ***
   630 
   631 * Antiquotation @{keyword "name"} produces a parser for outer syntax
   632 from a minor keyword introduced via theory header declaration.
   633 
   634 * Antiquotation @{command_spec "name"} produces the
   635 Outer_Syntax.command_spec from a major keyword introduced via theory
   636 header declaration; it can be passed to Outer_Syntax.command etc.
   637 
   638 * Local_Theory.define no longer hard-wires default theorem name
   639 "foo_def", but retains the binding as given.  If that is Binding.empty
   640 / Attrib.empty_binding, the result is not registered as user-level
   641 fact.  The Local_Theory.define_internal variant allows to specify a
   642 non-empty name (used for the foundation in the background theory),
   643 while omitting the fact binding in the user-context.  Potential
   644 INCOMPATIBILITY for derived definitional packages: need to specify
   645 naming policy for primitive definitions more explicitly.
   646 
   647 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
   648 conformance with similar operations in structure Term and Logic.
   649 
   650 * Antiquotation @{attributes [...]} embeds attribute source
   651 representation into the ML text, which is particularly useful with
   652 declarations like Local_Theory.note.
   653 
   654 * Structure Proof_Context follows standard naming scheme.  Old
   655 ProofContext has been discontinued.  INCOMPATIBILITY.
   656 
   657 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   658 change of semantics: update is applied to auxiliary local theory
   659 context as well.
   660 
   661 * Modernized some old-style infix operations:
   662 
   663   addeqcongs    ~> Simplifier.add_eqcong
   664   deleqcongs    ~> Simplifier.del_eqcong
   665   addcongs      ~> Simplifier.add_cong
   666   delcongs      ~> Simplifier.del_cong
   667   setmksimps    ~> Simplifier.set_mksimps
   668   setmkcong     ~> Simplifier.set_mkcong
   669   setmksym      ~> Simplifier.set_mksym
   670   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   671   settermless   ~> Simplifier.set_termless
   672   setsubgoaler  ~> Simplifier.set_subgoaler
   673   addsplits     ~> Splitter.add_split
   674   delsplits     ~> Splitter.del_split
   675 
   676 
   677 *** System ***
   678 
   679 * ISABELLE_HOME_WINDOWS refers to ISABELLE_HOME in windows file name
   680 notation, which is useful for the jEdit file browser, for example.
   681 
   682 
   683 
   684 New in Isabelle2011-1 (October 2011)
   685 ------------------------------------
   686 
   687 *** General ***
   688 
   689 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   690 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   691 
   692   - Management of multiple theory files directly from the editor
   693     buffer store -- bypassing the file-system (no requirement to save
   694     files for checking).
   695 
   696   - Markup of formal entities within the text buffer, with semantic
   697     highlighting, tooltips and hyperlinks to jump to defining source
   698     positions.
   699 
   700   - Improved text rendering, with sub/superscripts in the source
   701     buffer (including support for copy/paste wrt. output panel, HTML
   702     theory output and other non-Isabelle text boxes).
   703 
   704   - Refined scheduling of proof checking and printing of results,
   705     based on interactive editor view.  (Note: jEdit folding and
   706     narrowing allows to restrict buffer perspectives explicitly.)
   707 
   708   - Reduced CPU performance requirements, usable on machines with few
   709     cores.
   710 
   711   - Reduced memory requirements due to pruning of unused document
   712     versions (garbage collection).
   713 
   714 See also ~~/src/Tools/jEdit/README.html for further information,
   715 including some remaining limitations.
   716 
   717 * Theory loader: source files are exclusively located via the master
   718 directory of each theory node (where the .thy file itself resides).
   719 The global load path (such as src/HOL/Library) has been discontinued.
   720 Note that the path element ~~ may be used to reference theories in the
   721 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   722 INCOMPATIBILITY.
   723 
   724 * Theory loader: source files are identified by content via SHA1
   725 digests.  Discontinued former path/modtime identification and optional
   726 ISABELLE_FILE_IDENT plugin scripts.
   727 
   728 * Parallelization of nested Isar proofs is subject to
   729 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   730 usedir option -Q.
   731 
   732 * Name space: former unsynchronized references are now proper
   733 configuration options, with more conventional names:
   734 
   735   long_names   ~> names_long
   736   short_names  ~> names_short
   737   unique_names ~> names_unique
   738 
   739 Minor INCOMPATIBILITY, need to declare options in context like this:
   740 
   741   declare [[names_unique = false]]
   742 
   743 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   744 that the result needs to be unique, which means fact specifications
   745 may have to be refined after enriching a proof context.
   746 
   747 * Attribute "case_names" has been refined: the assumptions in each case
   748 can be named now by following the case name with [name1 name2 ...].
   749 
   750 * Isabelle/Isar reference manual has been updated and extended:
   751   - "Synopsis" provides a catalog of main Isar language concepts.
   752   - Formal references in syntax diagrams, via @{rail} antiquotation.
   753   - Updated material from classic "ref" manual, notably about
   754     "Classical Reasoner".
   755 
   756 
   757 *** HOL ***
   758 
   759 * Class bot and top require underlying partial order rather than
   760 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   761 
   762 * Class complete_lattice: generalized a couple of lemmas from sets;
   763 generalized theorems INF_cong and SUP_cong.  New type classes for
   764 complete boolean algebras and complete linear orders.  Lemmas
   765 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   766 class complete_linorder.
   767 
   768 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   769 Sup_fun_def, Inf_apply, Sup_apply.
   770 
   771 Removed redundant lemmas (the right hand side gives hints how to
   772 replace them for (metis ...), or (simp only: ...) proofs):
   773 
   774   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   775   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   776   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   777   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   778   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   779   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   780   Inter_def ~> INF_def, image_def
   781   Union_def ~> SUP_def, image_def
   782   INT_eq ~> INF_def, and image_def
   783   UN_eq ~> SUP_def, and image_def
   784   INF_subset ~> INF_superset_mono [OF _ order_refl]
   785 
   786 More consistent and comprehensive names:
   787 
   788   INTER_eq_Inter_image ~> INF_def
   789   UNION_eq_Union_image ~> SUP_def
   790   INFI_def ~> INF_def
   791   SUPR_def ~> SUP_def
   792   INF_leI ~> INF_lower
   793   INF_leI2 ~> INF_lower2
   794   le_INFI ~> INF_greatest
   795   le_SUPI ~> SUP_upper
   796   le_SUPI2 ~> SUP_upper2
   797   SUP_leI ~> SUP_least
   798   INFI_bool_eq ~> INF_bool_eq
   799   SUPR_bool_eq ~> SUP_bool_eq
   800   INFI_apply ~> INF_apply
   801   SUPR_apply ~> SUP_apply
   802   INTER_def ~> INTER_eq
   803   UNION_def ~> UNION_eq
   804 
   805 INCOMPATIBILITY.
   806 
   807 * Renamed theory Complete_Lattice to Complete_Lattices.
   808 INCOMPATIBILITY.
   809 
   810 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   811 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   812 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   813 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   814 
   815 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   816 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   817 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   818 INCOMPATIBILITY.
   819 
   820 * Added syntactic classes "inf" and "sup" for the respective
   821 constants.  INCOMPATIBILITY: Changes in the argument order of the
   822 (mostly internal) locale predicates for some derived classes.
   823 
   824 * Theorem collections ball_simps and bex_simps do not contain theorems
   825 referring to UNION any longer; these have been moved to collection
   826 UN_ball_bex_simps.  INCOMPATIBILITY.
   827 
   828 * Theory Archimedean_Field: floor now is defined as parameter of a
   829 separate type class floor_ceiling.
   830 
   831 * Theory Finite_Set: more coherent development of fold_set locales:
   832 
   833     locale fun_left_comm ~> locale comp_fun_commute
   834     locale fun_left_comm_idem ~> locale comp_fun_idem
   835 
   836 Both use point-free characterization; interpretation proofs may need
   837 adjustment.  INCOMPATIBILITY.
   838 
   839 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   840 accordance with standard mathematical terminology. INCOMPATIBILITY.
   841 
   842 * Theory Complex_Main: The locale interpretations for the
   843 bounded_linear and bounded_bilinear locales have been removed, in
   844 order to reduce the number of duplicate lemmas. Users must use the
   845 original names for distributivity theorems, potential INCOMPATIBILITY.
   846 
   847   divide.add ~> add_divide_distrib
   848   divide.diff ~> diff_divide_distrib
   849   divide.setsum ~> setsum_divide_distrib
   850   mult.add_right ~> right_distrib
   851   mult.diff_right ~> right_diff_distrib
   852   mult_right.setsum ~> setsum_right_distrib
   853   mult_left.diff ~> left_diff_distrib
   854 
   855 * Theory Complex_Main: Several redundant theorems have been removed or
   856 replaced by more general versions. INCOMPATIBILITY.
   857 
   858   real_diff_def ~> minus_real_def
   859   real_divide_def ~> divide_real_def
   860   real_less_def ~> less_le
   861   real_abs_def ~> abs_real_def
   862   real_sgn_def ~> sgn_real_def
   863   real_mult_commute ~> mult_commute
   864   real_mult_assoc ~> mult_assoc
   865   real_mult_1 ~> mult_1_left
   866   real_add_mult_distrib ~> left_distrib
   867   real_zero_not_eq_one ~> zero_neq_one
   868   real_mult_inverse_left ~> left_inverse
   869   INVERSE_ZERO ~> inverse_zero
   870   real_le_refl ~> order_refl
   871   real_le_antisym ~> order_antisym
   872   real_le_trans ~> order_trans
   873   real_le_linear ~> linear
   874   real_le_eq_diff ~> le_iff_diff_le_0
   875   real_add_left_mono ~> add_left_mono
   876   real_mult_order ~> mult_pos_pos
   877   real_mult_less_mono2 ~> mult_strict_left_mono
   878   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   879   real_0_le_divide_iff ~> zero_le_divide_iff
   880   realpow_two_disj ~> power2_eq_iff
   881   real_squared_diff_one_factored ~> square_diff_one_factored
   882   realpow_two_diff ~> square_diff_square_factored
   883   reals_complete2 ~> complete_real
   884   real_sum_squared_expand ~> power2_sum
   885   exp_ln_eq ~> ln_unique
   886   expi_add ~> exp_add
   887   expi_zero ~> exp_zero
   888   lemma_DERIV_subst ~> DERIV_cong
   889   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   890   LIMSEQ_const ~> tendsto_const
   891   LIMSEQ_norm ~> tendsto_norm
   892   LIMSEQ_add ~> tendsto_add
   893   LIMSEQ_minus ~> tendsto_minus
   894   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   895   LIMSEQ_diff ~> tendsto_diff
   896   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   897   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   898   LIMSEQ_mult ~> tendsto_mult
   899   LIMSEQ_inverse ~> tendsto_inverse
   900   LIMSEQ_divide ~> tendsto_divide
   901   LIMSEQ_pow ~> tendsto_power
   902   LIMSEQ_setsum ~> tendsto_setsum
   903   LIMSEQ_setprod ~> tendsto_setprod
   904   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   905   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   906   LIMSEQ_imp_rabs ~> tendsto_rabs
   907   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   908   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   909   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   910   LIMSEQ_Complex ~> tendsto_Complex
   911   LIM_ident ~> tendsto_ident_at
   912   LIM_const ~> tendsto_const
   913   LIM_add ~> tendsto_add
   914   LIM_add_zero ~> tendsto_add_zero
   915   LIM_minus ~> tendsto_minus
   916   LIM_diff ~> tendsto_diff
   917   LIM_norm ~> tendsto_norm
   918   LIM_norm_zero ~> tendsto_norm_zero
   919   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   920   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   921   LIM_rabs ~> tendsto_rabs
   922   LIM_rabs_zero ~> tendsto_rabs_zero
   923   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   924   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   925   LIM_compose ~> tendsto_compose
   926   LIM_mult ~> tendsto_mult
   927   LIM_scaleR ~> tendsto_scaleR
   928   LIM_of_real ~> tendsto_of_real
   929   LIM_power ~> tendsto_power
   930   LIM_inverse ~> tendsto_inverse
   931   LIM_sgn ~> tendsto_sgn
   932   isCont_LIM_compose ~> isCont_tendsto_compose
   933   bounded_linear.LIM ~> bounded_linear.tendsto
   934   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   935   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   936   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   937   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   938   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   939   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   940 
   941 * Theory Complex_Main: The definition of infinite series was
   942 generalized.  Now it is defined on the type class {topological_space,
   943 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   944 
   945 * Theory Complex_Main: The complex exponential function "expi" is now
   946 a type-constrained abbreviation for "exp :: complex => complex"; thus
   947 several polymorphic lemmas about "exp" are now applicable to "expi".
   948 
   949 * Code generation:
   950 
   951   - Theory Library/Code_Char_ord provides native ordering of
   952     characters in the target language.
   953 
   954   - Commands code_module and code_library are legacy, use export_code
   955     instead.
   956 
   957   - Method "evaluation" is legacy, use method "eval" instead.
   958 
   959   - Legacy evaluator "SML" is deactivated by default.  May be
   960     reactivated by the following theory command:
   961 
   962       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   963 
   964 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   965 
   966 * New proof method "induction" that gives induction hypotheses the
   967 name "IH", thus distinguishing them from further hypotheses that come
   968 from rule induction.  The latter are still called "hyps".  Method
   969 "induction" is a thin wrapper around "induct" and follows the same
   970 syntax.
   971 
   972 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
   973 still available as a legacy feature for some time.
   974 
   975 * Nitpick:
   976   - Added "need" and "total_consts" options.
   977   - Reintroduced "show_skolems" option by popular demand.
   978   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   979     INCOMPATIBILITY.
   980 
   981 * Sledgehammer:
   982   - Use quasi-sound (and efficient) translations by default.
   983   - Added support for the following provers: E-ToFoF, LEO-II,
   984     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
   985   - Automatically preplay and minimize proofs before showing them if
   986     this can be done within reasonable time.
   987   - sledgehammer available_provers ~> sledgehammer supported_provers.
   988     INCOMPATIBILITY.
   989   - Added "preplay_timeout", "slicing", "type_enc", "sound",
   990     "max_mono_iters", and "max_new_mono_instances" options.
   991   - Removed "explicit_apply" and "full_types" options as well as "Full
   992     Types" Proof General menu item. INCOMPATIBILITY.
   993 
   994 * Metis:
   995   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   996   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
   997     INCOMPATIBILITY.
   998 
   999 * Command 'try':
  1000   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
  1001     "elim:" options. INCOMPATIBILITY.
  1002   - Introduced 'try' that not only runs 'try_methods' but also
  1003     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
  1004 
  1005 * Quickcheck:
  1006   - Added "eval" option to evaluate terms for the found counterexample
  1007     (currently only supported by the default (exhaustive) tester).
  1008   - Added post-processing of terms to obtain readable counterexamples
  1009     (currently only supported by the default (exhaustive) tester).
  1010   - New counterexample generator quickcheck[narrowing] enables
  1011     narrowing-based testing.  Requires the Glasgow Haskell compiler
  1012     with its installation location defined in the Isabelle settings
  1013     environment as ISABELLE_GHC.
  1014   - Removed quickcheck tester "SML" based on the SML code generator
  1015     (formly in HOL/Library).
  1016 
  1017 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
  1018 use 'partial_function' instead.
  1019 
  1020 * Theory Library/Extended_Reals replaces now the positive extended
  1021 reals found in probability theory. This file is extended by
  1022 Multivariate_Analysis/Extended_Real_Limits.
  1023 
  1024 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
  1025 from where it must be imported explicitly if it is really required.
  1026 INCOMPATIBILITY.
  1027 
  1028 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
  1029 been moved here.  INCOMPATIBILITY.
  1030 
  1031 * Theory Library/Saturated provides type of numbers with saturated
  1032 arithmetic.
  1033 
  1034 * Theory Library/Product_Lattice defines a pointwise ordering for the
  1035 product type 'a * 'b, and provides instance proofs for various order
  1036 and lattice type classes.
  1037 
  1038 * Theory Library/Countable now provides the "countable_datatype" proof
  1039 method for proving "countable" class instances for datatypes.
  1040 
  1041 * Theory Library/Cset_Monad allows do notation for computable sets
  1042 (cset) via the generic monad ad-hoc overloading facility.
  1043 
  1044 * Library: Theories of common data structures are split into theories
  1045 for implementation, an invariant-ensuring type, and connection to an
  1046 abstract type. INCOMPATIBILITY.
  1047 
  1048   - RBT is split into RBT and RBT_Mapping.
  1049   - AssocList is split and renamed into AList and AList_Mapping.
  1050   - DList is split into DList_Impl, DList, and DList_Cset.
  1051   - Cset is split into Cset and List_Cset.
  1052 
  1053 * Theory Library/Nat_Infinity has been renamed to
  1054 Library/Extended_Nat, with name changes of the following types and
  1055 constants:
  1056 
  1057   type inat   ~> type enat
  1058   Fin         ~> enat
  1059   Infty       ~> infinity (overloaded)
  1060   iSuc        ~> eSuc
  1061   the_Fin     ~> the_enat
  1062 
  1063 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
  1064 been renamed accordingly. INCOMPATIBILITY.
  1065 
  1066 * Session Multivariate_Analysis: The euclidean_space type class now
  1067 fixes a constant "Basis :: 'a set" consisting of the standard
  1068 orthonormal basis for the type. Users now have the option of
  1069 quantifying over this set instead of using the "basis" function, e.g.
  1070 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
  1071 
  1072 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
  1073 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
  1074 "Cart_nth" and "Cart_lambda" have been respectively renamed to
  1075 "vec_nth" and "vec_lambda"; theorems mentioning those names have
  1076 changed to match. Definition theorems for overloaded constants now use
  1077 the standard "foo_vec_def" naming scheme. A few other theorems have
  1078 been renamed as follows (INCOMPATIBILITY):
  1079 
  1080   Cart_eq          ~> vec_eq_iff
  1081   dist_nth_le_cart ~> dist_vec_nth_le
  1082   tendsto_vector   ~> vec_tendstoI
  1083   Cauchy_vector    ~> vec_CauchyI
  1084 
  1085 * Session Multivariate_Analysis: Several duplicate theorems have been
  1086 removed, and other theorems have been renamed or replaced with more
  1087 general versions. INCOMPATIBILITY.
  1088 
  1089   finite_choice ~> finite_set_choice
  1090   eventually_conjI ~> eventually_conj
  1091   eventually_and ~> eventually_conj_iff
  1092   eventually_false ~> eventually_False
  1093   setsum_norm ~> norm_setsum
  1094   Lim_sequentially ~> LIMSEQ_def
  1095   Lim_ident_at ~> LIM_ident
  1096   Lim_const ~> tendsto_const
  1097   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
  1098   Lim_neg ~> tendsto_minus
  1099   Lim_add ~> tendsto_add
  1100   Lim_sub ~> tendsto_diff
  1101   Lim_mul ~> tendsto_scaleR
  1102   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
  1103   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
  1104   Lim_linear ~> bounded_linear.tendsto
  1105   Lim_component ~> tendsto_euclidean_component
  1106   Lim_component_cart ~> tendsto_vec_nth
  1107   Lim_inner ~> tendsto_inner [OF tendsto_const]
  1108   dot_lsum ~> inner_setsum_left
  1109   dot_rsum ~> inner_setsum_right
  1110   continuous_cmul ~> continuous_scaleR [OF continuous_const]
  1111   continuous_neg ~> continuous_minus
  1112   continuous_sub ~> continuous_diff
  1113   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
  1114   continuous_mul ~> continuous_scaleR
  1115   continuous_inv ~> continuous_inverse
  1116   continuous_at_within_inv ~> continuous_at_within_inverse
  1117   continuous_at_inv ~> continuous_at_inverse
  1118   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
  1119   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
  1120   continuous_at_component ~> continuous_component [OF continuous_at_id]
  1121   continuous_on_neg ~> continuous_on_minus
  1122   continuous_on_sub ~> continuous_on_diff
  1123   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
  1124   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
  1125   continuous_on_mul ~> continuous_on_scaleR
  1126   continuous_on_mul_real ~> continuous_on_mult
  1127   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
  1128   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
  1129   continuous_on_inverse ~> continuous_on_inv
  1130   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
  1131   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
  1132   subset_interior ~> interior_mono
  1133   subset_closure ~> closure_mono
  1134   closure_univ ~> closure_UNIV
  1135   real_arch_lt ~> reals_Archimedean2
  1136   real_arch ~> reals_Archimedean3
  1137   real_abs_norm ~> abs_norm_cancel
  1138   real_abs_sub_norm ~> norm_triangle_ineq3
  1139   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
  1140 
  1141 * Session HOL-Probability:
  1142   - Caratheodory's extension lemma is now proved for ring_of_sets.
  1143   - Infinite products of probability measures are now available.
  1144   - Sigma closure is independent, if the generator is independent
  1145   - Use extended reals instead of positive extended
  1146     reals. INCOMPATIBILITY.
  1147 
  1148 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
  1149 
  1150   expand_fun_below ~> fun_below_iff
  1151   below_fun_ext ~> fun_belowI
  1152   expand_cfun_eq ~> cfun_eq_iff
  1153   ext_cfun ~> cfun_eqI
  1154   expand_cfun_below ~> cfun_below_iff
  1155   below_cfun_ext ~> cfun_belowI
  1156   monofun_fun_fun ~> fun_belowD
  1157   monofun_fun_arg ~> monofunE
  1158   monofun_lub_fun ~> adm_monofun [THEN admD]
  1159   cont_lub_fun ~> adm_cont [THEN admD]
  1160   cont2cont_Rep_CFun ~> cont2cont_APP
  1161   cont_Rep_CFun_app ~> cont_APP_app
  1162   cont_Rep_CFun_app_app ~> cont_APP_app_app
  1163   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
  1164   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
  1165   contlub_cfun ~> lub_APP [symmetric]
  1166   contlub_LAM ~> lub_LAM [symmetric]
  1167   thelubI ~> lub_eqI
  1168   UU_I ~> bottomI
  1169   lift_distinct1 ~> lift.distinct(1)
  1170   lift_distinct2 ~> lift.distinct(2)
  1171   Def_not_UU ~> lift.distinct(2)
  1172   Def_inject ~> lift.inject
  1173   below_UU_iff ~> below_bottom_iff
  1174   eq_UU_iff ~> eq_bottom_iff
  1175 
  1176 
  1177 *** Document preparation ***
  1178 
  1179 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
  1180 isar-ref manual, both for description and actual application of the
  1181 same.
  1182 
  1183 * Antiquotation @{value} evaluates the given term and presents its
  1184 result.
  1185 
  1186 * Antiquotations: term style "isub" provides ad-hoc conversion of
  1187 variables x1, y23 into subscripted form x\<^isub>1,
  1188 y\<^isub>2\<^isub>3.
  1189 
  1190 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
  1191 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
  1192 
  1193 * Localized \isabellestyle switch can be used within blocks or groups
  1194 like this:
  1195 
  1196   \isabellestyle{it}  %preferred default
  1197   {\isabellestylett @{text "typewriter stuff"}}
  1198 
  1199 * Discontinued special treatment of hard tabulators.  Implicit
  1200 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
  1201 layouts.
  1202 
  1203 
  1204 *** ML ***
  1205 
  1206 * The inner syntax of sort/type/term/prop supports inlined YXML
  1207 representations within quoted string tokens.  By encoding logical
  1208 entities via Term_XML (in ML or Scala) concrete syntax can be
  1209 bypassed, which is particularly useful for producing bits of text
  1210 under external program control.
  1211 
  1212 * Antiquotations for ML and document preparation are managed as theory
  1213 data, which requires explicit setup.
  1214 
  1215 * Isabelle_Process.is_active allows tools to check if the official
  1216 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
  1217 (better known as Proof General).
  1218 
  1219 * Structure Proof_Context follows standard naming scheme.  Old
  1220 ProofContext is still available for some time as legacy alias.
  1221 
  1222 * Structure Timing provides various operations for timing; supersedes
  1223 former start_timing/end_timing etc.
  1224 
  1225 * Path.print is the official way to show file-system paths to users
  1226 (including quotes etc.).
  1227 
  1228 * Inner syntax: identifiers in parse trees of generic categories
  1229 "logic", "aprop", "idt" etc. carry position information (disguised as
  1230 type constraints).  Occasional INCOMPATIBILITY with non-compliant
  1231 translations that choke on unexpected type constraints.  Positions can
  1232 be stripped in ML translations via Syntax.strip_positions /
  1233 Syntax.strip_positions_ast, or via the syntax constant
  1234 "_strip_positions" within parse trees.  As last resort, positions can
  1235 be disabled via the configuration option Syntax.positions, which is
  1236 called "syntax_positions" in Isar attribute syntax.
  1237 
  1238 * Discontinued special status of various ML structures that contribute
  1239 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
  1240 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
  1241 refer directly to Ast.Constant, Lexicon.is_identifier,
  1242 Syntax_Trans.mk_binder_tr etc.
  1243 
  1244 * Typed print translation: discontinued show_sorts argument, which is
  1245 already available via context of "advanced" translation.
  1246 
  1247 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
  1248 goal states; body tactic needs to address all subgoals uniformly.
  1249 
  1250 * Slightly more special eq_list/eq_set, with shortcut involving
  1251 pointer equality (assumes that eq relation is reflexive).
  1252 
  1253 * Classical tactics use proper Proof.context instead of historic types
  1254 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  1255 operate directly on Proof.context.  Raw type claset retains its use as
  1256 snapshot of the classical context, which can be recovered via
  1257 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  1258 INCOMPATIBILITY, classical tactics and derived proof methods require
  1259 proper Proof.context.
  1260 
  1261 
  1262 *** System ***
  1263 
  1264 * Discontinued support for Poly/ML 5.2, which was the last version
  1265 without proper multithreading and TimeLimit implementation.
  1266 
  1267 * Discontinued old lib/scripts/polyml-platform, which has been
  1268 obsolete since Isabelle2009-2.
  1269 
  1270 * Various optional external tools are referenced more robustly and
  1271 uniformly by explicit Isabelle settings as follows:
  1272 
  1273   ISABELLE_CSDP   (formerly CSDP_EXE)
  1274   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  1275   ISABELLE_OCAML  (formerly EXEC_OCAML)
  1276   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  1277   ISABELLE_YAP    (formerly EXEC_YAP)
  1278 
  1279 Note that automated detection from the file-system or search path has
  1280 been discontinued.  INCOMPATIBILITY.
  1281 
  1282 * Scala layer provides JVM method invocation service for static
  1283 methods of type (String)String, see Invoke_Scala.method in ML.  For
  1284 example:
  1285 
  1286   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  1287 
  1288 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  1289 this allows to pass structured values between ML and Scala.
  1290 
  1291 * The IsabelleText fonts includes some further glyphs to support the
  1292 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  1293 installed a local copy (which is normally *not* required) need to
  1294 delete or update it from ~~/lib/fonts/.
  1295 
  1296 
  1297 
  1298 New in Isabelle2011 (January 2011)
  1299 ----------------------------------
  1300 
  1301 *** General ***
  1302 
  1303 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  1304 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  1305 useful tooltips and hyperlinks produced from its static analysis.  The
  1306 bundled component provides an executable Isabelle tool that can be run
  1307 like this:
  1308 
  1309   Isabelle2011/bin/isabelle jedit
  1310 
  1311 * Significantly improved Isabelle/Isar implementation manual.
  1312 
  1313 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  1314 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  1315 while the default heap location within that directory lacks that extra
  1316 suffix.  This isolates multiple Isabelle installations from each
  1317 other, avoiding problems with old settings in new versions.
  1318 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  1319 
  1320 * Source files are always encoded as UTF-8, instead of old-fashioned
  1321 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  1322 the following package declarations:
  1323 
  1324   \usepackage[utf8]{inputenc}
  1325   \usepackage{textcomp}
  1326 
  1327 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  1328 a Unicode character is treated as a single symbol, not a sequence of
  1329 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  1330 contain symbols without further backslash escapes, Unicode can now be
  1331 used here as well.  Recall that Symbol.explode in ML provides a
  1332 consistent view on symbols, while raw explode (or String.explode)
  1333 merely give a byte-oriented representation.
  1334 
  1335 * Theory loader: source files are primarily located via the master
  1336 directory of each theory node (where the .thy file itself resides).
  1337 The global load path is still partially available as legacy feature.
  1338 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  1339 explicit paths, relatively to the theory.
  1340 
  1341 * Special treatment of ML file names has been discontinued.
  1342 Historically, optional extensions .ML or .sml were added on demand --
  1343 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  1344 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  1345 
  1346 * Various options that affect pretty printing etc. are now properly
  1347 handled within the context via configuration options, instead of
  1348 unsynchronized references or print modes.  There are both ML Config.T
  1349 entities and Isar declaration attributes to access these.
  1350 
  1351   ML (Config.T)                 Isar (attribute)
  1352 
  1353   eta_contract                  eta_contract
  1354   show_brackets                 show_brackets
  1355   show_sorts                    show_sorts
  1356   show_types                    show_types
  1357   show_question_marks           show_question_marks
  1358   show_consts                   show_consts
  1359   show_abbrevs                  show_abbrevs
  1360 
  1361   Syntax.ast_trace              syntax_ast_trace
  1362   Syntax.ast_stat               syntax_ast_stat
  1363   Syntax.ambiguity_level        syntax_ambiguity_level
  1364 
  1365   Goal_Display.goals_limit      goals_limit
  1366   Goal_Display.show_main_goal   show_main_goal
  1367 
  1368   Method.rule_trace             rule_trace
  1369 
  1370   Thy_Output.display            thy_output_display
  1371   Thy_Output.quotes             thy_output_quotes
  1372   Thy_Output.indent             thy_output_indent
  1373   Thy_Output.source             thy_output_source
  1374   Thy_Output.break              thy_output_break
  1375 
  1376 Note that corresponding "..._default" references in ML may only be
  1377 changed globally at the ROOT session setup, but *not* within a theory.
  1378 The option "show_abbrevs" supersedes the former print mode
  1379 "no_abbrevs" with inverted meaning.
  1380 
  1381 * More systematic naming of some configuration options.
  1382 INCOMPATIBILITY.
  1383 
  1384   trace_simp  ~>  simp_trace
  1385   debug_simp  ~>  simp_debug
  1386 
  1387 * Support for real valued configuration options, using simplistic
  1388 floating-point notation that coincides with the inner syntax for
  1389 float_token.
  1390 
  1391 * Support for real valued preferences (with approximative PGIP type):
  1392 front-ends need to accept "pgint" values in float notation.
  1393 INCOMPATIBILITY.
  1394 
  1395 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  1396 DejaVu Sans.
  1397 
  1398 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  1399 
  1400 
  1401 *** Pure ***
  1402 
  1403 * Command 'type_synonym' (with single argument) replaces somewhat
  1404 outdated 'types', which is still available as legacy feature for some
  1405 time.
  1406 
  1407 * Command 'nonterminal' (with 'and' separated list of arguments)
  1408 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  1409 
  1410 * Command 'notepad' replaces former 'example_proof' for
  1411 experimentation in Isar without any result.  INCOMPATIBILITY.
  1412 
  1413 * Locale interpretation commands 'interpret' and 'sublocale' accept
  1414 lists of equations to map definitions in a locale to appropriate
  1415 entities in the context of the interpretation.  The 'interpretation'
  1416 command already provided this functionality.
  1417 
  1418 * Diagnostic command 'print_dependencies' prints the locale instances
  1419 that would be activated if the specified expression was interpreted in
  1420 the current context.  Variant "print_dependencies!" assumes a context
  1421 without interpretations.
  1422 
  1423 * Diagnostic command 'print_interps' prints interpretations in proofs
  1424 in addition to interpretations in theories.
  1425 
  1426 * Discontinued obsolete 'global' and 'local' commands to manipulate
  1427 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  1428 Sign.root_path and Sign.local_path may be applied directly where this
  1429 feature is still required for historical reasons.
  1430 
  1431 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  1432 'definition' instead.
  1433 
  1434 * The "prems" fact, which refers to the accidental collection of
  1435 foundational premises in the context, is now explicitly marked as
  1436 legacy feature and will be discontinued soon.  Consider using "assms"
  1437 of the head statement or reference facts by explicit names.
  1438 
  1439 * Document antiquotations @{class} and @{type} print classes and type
  1440 constructors.
  1441 
  1442 * Document antiquotation @{file} checks file/directory entries within
  1443 the local file system.
  1444 
  1445 
  1446 *** HOL ***
  1447 
  1448 * Coercive subtyping: functions can be declared as coercions and type
  1449 inference will add them as necessary upon input of a term.  Theory
  1450 Complex_Main declares real :: nat => real and real :: int => real as
  1451 coercions. A coercion function f is declared like this:
  1452 
  1453   declare [[coercion f]]
  1454 
  1455 To lift coercions through type constructors (e.g. from nat => real to
  1456 nat list => real list), map functions can be declared, e.g.
  1457 
  1458   declare [[coercion_map map]]
  1459 
  1460 Currently coercion inference is activated only in theories including
  1461 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1462 the configuration option "coercion_enabled", e.g. it can be enabled in
  1463 other theories like this:
  1464 
  1465   declare [[coercion_enabled]]
  1466 
  1467 * Command 'partial_function' provides basic support for recursive
  1468 function definitions over complete partial orders.  Concrete instances
  1469 are provided for i) the option type, ii) tail recursion on arbitrary
  1470 types, and iii) the heap monad of Imperative_HOL.  See
  1471 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1472 for examples.
  1473 
  1474 * Function package: f.psimps rules are no longer implicitly declared
  1475 as [simp].  INCOMPATIBILITY.
  1476 
  1477 * Datatype package: theorems generated for executable equality (class
  1478 "eq") carry proper names and are treated as default code equations.
  1479 
  1480 * Inductive package: now offers command 'inductive_simps' to
  1481 automatically derive instantiated and simplified equations for
  1482 inductive predicates, similar to 'inductive_cases'.
  1483 
  1484 * Command 'enriched_type' allows to register properties of the
  1485 functorial structure of types.
  1486 
  1487 * Improved infrastructure for term evaluation using code generator
  1488 techniques, in particular static evaluation conversions.
  1489 
  1490 * Code generator: Scala (2.8 or higher) has been added to the target
  1491 languages.
  1492 
  1493 * Code generator: globbing constant expressions "*" and "Theory.*"
  1494 have been replaced by the more idiomatic "_" and "Theory._".
  1495 INCOMPATIBILITY.
  1496 
  1497 * Code generator: export_code without explicit file declaration prints
  1498 to standard output.  INCOMPATIBILITY.
  1499 
  1500 * Code generator: do not print function definitions for case
  1501 combinators any longer.
  1502 
  1503 * Code generator: simplification with rules determined with
  1504 src/Tools/Code/code_simp.ML and method "code_simp".
  1505 
  1506 * Code generator for records: more idiomatic representation of record
  1507 types.  Warning: records are not covered by ancient SML code
  1508 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1509 rep_datatype declaration helps to succeed then:
  1510 
  1511   record 'a foo = ...
  1512   ...
  1513   rep_datatype foo_ext ...
  1514 
  1515 * Records: logical foundation type for records does not carry a
  1516 '_type' suffix any longer (obsolete due to authentic syntax).
  1517 INCOMPATIBILITY.
  1518 
  1519 * Quickcheck now by default uses exhaustive testing instead of random
  1520 testing.  Random testing can be invoked by "quickcheck [random]",
  1521 exhaustive testing by "quickcheck [exhaustive]".
  1522 
  1523 * Quickcheck instantiates polymorphic types with small finite
  1524 datatypes by default. This enables a simple execution mechanism to
  1525 handle quantifiers and function equality over the finite datatypes.
  1526 
  1527 * Quickcheck random generator has been renamed from "code" to
  1528 "random".  INCOMPATIBILITY.
  1529 
  1530 * Quickcheck now has a configurable time limit which is set to 30
  1531 seconds by default. This can be changed by adding [timeout = n] to the
  1532 quickcheck command. The time limit for Auto Quickcheck is still set
  1533 independently.
  1534 
  1535 * Quickcheck in locales considers interpretations of that locale for
  1536 counter example search.
  1537 
  1538 * Sledgehammer:
  1539   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1540     method. See the Sledgehammer manual for details ("isabelle doc
  1541     sledgehammer").
  1542   - Renamed commands:
  1543     sledgehammer atp_info ~> sledgehammer running_provers
  1544     sledgehammer atp_kill ~> sledgehammer kill_provers
  1545     sledgehammer available_atps ~> sledgehammer available_provers
  1546     INCOMPATIBILITY.
  1547   - Renamed options:
  1548     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1549     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1550     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1551     (and "ms" and "min" are no longer supported)
  1552     INCOMPATIBILITY.
  1553 
  1554 * Nitpick:
  1555   - Renamed options:
  1556     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1557     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1558     INCOMPATIBILITY.
  1559   - Added support for partial quotient types.
  1560   - Added local versions of the "Nitpick.register_xxx" functions.
  1561   - Added "whack" option.
  1562   - Allow registration of quotient types as codatatypes.
  1563   - Improved "merge_type_vars" option to merge more types.
  1564   - Removed unsound "fast_descrs" option.
  1565   - Added custom symmetry breaking for datatypes, making it possible to reach
  1566     higher cardinalities.
  1567   - Prevent the expansion of too large definitions.
  1568 
  1569 * Proof methods "metis" and "meson" now have configuration options
  1570 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1571 to diagnose these tools. E.g.
  1572 
  1573     using [[metis_trace = true]]
  1574 
  1575 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1576 manually as command 'solve_direct'.
  1577 
  1578 * The default SMT solver Z3 must be enabled explicitly (due to
  1579 licensing issues) by setting the environment variable
  1580 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1581 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1582 changing the SMT solver is done via the configuration option
  1583 "smt_solver".
  1584 
  1585 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1586 i.e. "remote_cvc3" and "remote_z3".
  1587 
  1588 * Added basic SMT support for datatypes, records, and typedefs using
  1589 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1590 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1591 support for a similar behavior).  Minor INCOMPATIBILITY.
  1592 
  1593 * Changed SMT configuration options:
  1594   - Renamed:
  1595     z3_proofs ~> smt_oracle (with inverted meaning)
  1596     z3_trace_assms ~> smt_trace_used_facts
  1597     INCOMPATIBILITY.
  1598   - Added:
  1599     smt_verbose
  1600     smt_random_seed
  1601     smt_datatypes
  1602     smt_infer_triggers
  1603     smt_monomorph_limit
  1604     cvc3_options
  1605     remote_cvc3_options
  1606     remote_z3_options
  1607     yices_options
  1608 
  1609 * Boogie output files (.b2i files) need to be declared in the theory
  1610 header.
  1611 
  1612 * Simplification procedure "list_to_set_comprehension" rewrites list
  1613 comprehensions applied to List.set to set comprehensions.  Occasional
  1614 INCOMPATIBILITY, may be deactivated like this:
  1615 
  1616   declare [[simproc del: list_to_set_comprehension]]
  1617 
  1618 * Removed old version of primrec package.  INCOMPATIBILITY.
  1619 
  1620 * Removed simplifier congruence rule of "prod_case", as has for long
  1621 been the case with "split".  INCOMPATIBILITY.
  1622 
  1623 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1624 
  1625 * Removed [split_format ... and ... and ...] version of
  1626 [split_format].  Potential INCOMPATIBILITY.
  1627 
  1628 * Predicate "sorted" now defined inductively, with nice induction
  1629 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1630 
  1631 * Constant "contents" renamed to "the_elem", to free the generic name
  1632 contents for other uses.  INCOMPATIBILITY.
  1633 
  1634 * Renamed class eq and constant eq (for code generation) to class
  1635 equal and constant equal, plus renaming of related facts and various
  1636 tuning.  INCOMPATIBILITY.
  1637 
  1638 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1639 
  1640 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1641 INCOMPATIBILITY.
  1642 
  1643 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1644 avoid confusion with finite sets.  INCOMPATIBILITY.
  1645 
  1646 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1647 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1648 for congruent(2)).
  1649 
  1650 * Some previously unqualified names have been qualified:
  1651 
  1652   types
  1653     bool ~> HOL.bool
  1654     nat ~> Nat.nat
  1655 
  1656   constants
  1657     Trueprop ~> HOL.Trueprop
  1658     True ~> HOL.True
  1659     False ~> HOL.False
  1660     op & ~> HOL.conj
  1661     op | ~> HOL.disj
  1662     op --> ~> HOL.implies
  1663     op = ~> HOL.eq
  1664     Not ~> HOL.Not
  1665     The ~> HOL.The
  1666     All ~> HOL.All
  1667     Ex ~> HOL.Ex
  1668     Ex1 ~> HOL.Ex1
  1669     Let ~> HOL.Let
  1670     If ~> HOL.If
  1671     Ball ~> Set.Ball
  1672     Bex ~> Set.Bex
  1673     Suc ~> Nat.Suc
  1674     Pair ~> Product_Type.Pair
  1675     fst ~> Product_Type.fst
  1676     snd ~> Product_Type.snd
  1677     curry ~> Product_Type.curry
  1678     op : ~> Set.member
  1679     Collect ~> Set.Collect
  1680 
  1681 INCOMPATIBILITY.
  1682 
  1683 * More canonical naming convention for some fundamental definitions:
  1684 
  1685     bot_bool_eq ~> bot_bool_def
  1686     top_bool_eq ~> top_bool_def
  1687     inf_bool_eq ~> inf_bool_def
  1688     sup_bool_eq ~> sup_bool_def
  1689     bot_fun_eq  ~> bot_fun_def
  1690     top_fun_eq  ~> top_fun_def
  1691     inf_fun_eq  ~> inf_fun_def
  1692     sup_fun_eq  ~> sup_fun_def
  1693 
  1694 INCOMPATIBILITY.
  1695 
  1696 * More stylized fact names:
  1697 
  1698   expand_fun_eq ~> fun_eq_iff
  1699   expand_set_eq ~> set_eq_iff
  1700   set_ext       ~> set_eqI
  1701   nat_number    ~> eval_nat_numeral
  1702 
  1703 INCOMPATIBILITY.
  1704 
  1705 * Refactoring of code-generation specific operations in theory List:
  1706 
  1707   constants
  1708     null ~> List.null
  1709 
  1710   facts
  1711     mem_iff ~> member_def
  1712     null_empty ~> null_def
  1713 
  1714 INCOMPATIBILITY.  Note that these were not supposed to be used
  1715 regularly unless for striking reasons; their main purpose was code
  1716 generation.
  1717 
  1718 Various operations from the Haskell prelude are used for generating
  1719 Haskell code.
  1720 
  1721 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1722 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1723 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1724 
  1725 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1726 "*" and "+" respectively.  INCOMPATIBILITY.
  1727 
  1728 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1729 "Sum_Type.Plus" instead.
  1730 
  1731 * Constant "split" has been merged with constant "prod_case"; names of
  1732 ML functions, facts etc. involving split have been retained so far,
  1733 though.  INCOMPATIBILITY.
  1734 
  1735 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1736 instead.  INCOMPATIBILITY.
  1737 
  1738 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1739 INCOMPATIBILITY.
  1740 
  1741 * Former theory Library/Enum is now part of the HOL-Main image.
  1742 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1743 referred to by its qualified name.
  1744 
  1745   enum    ~>  Enum.enum
  1746   nlists  ~>  Enum.nlists
  1747   product ~>  Enum.product
  1748 
  1749 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1750 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1751 INCOMPATIBILITY.
  1752 
  1753 * Theory Library/SetsAndFunctions has been split into
  1754 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1755 for instance definitions for functions; various improvements.
  1756 INCOMPATIBILITY.
  1757 
  1758 * Theory Library/Multiset provides stable quicksort implementation of
  1759 sort_key.
  1760 
  1761 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1762 INCOMPATIBILITY.
  1763 
  1764 * Session Multivariate_Analysis: introduced a type class for euclidean
  1765 space.  Most theorems are now stated in terms of euclidean spaces
  1766 instead of finite cartesian products.
  1767 
  1768   types
  1769     real ^ 'n ~>  'a::real_vector
  1770               ~>  'a::euclidean_space
  1771               ~>  'a::ordered_euclidean_space
  1772         (depends on your needs)
  1773 
  1774   constants
  1775      _ $ _        ~> _ $$ _
  1776      \<chi> x. _  ~> \<chi>\<chi> x. _
  1777      CARD('n)     ~> DIM('a)
  1778 
  1779 Also note that the indices are now natural numbers and not from some
  1780 finite type. Finite cartesian products of euclidean spaces, products
  1781 of euclidean spaces the real and complex numbers are instantiated to
  1782 be euclidean_spaces.  INCOMPATIBILITY.
  1783 
  1784 * Session Probability: introduced pextreal as positive extended real
  1785 numbers.  Use pextreal as value for measures.  Introduce the
  1786 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1787 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1788 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1789 
  1790 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1791 INCOMPATIBILITY.
  1792 
  1793 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1794 prove verification conditions generated by the SPARK Ada program
  1795 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1796 
  1797 
  1798 *** HOL-Algebra ***
  1799 
  1800 * Theorems for additive ring operations (locale abelian_monoid and
  1801 descendants) are generated by interpretation from their multiplicative
  1802 counterparts.  Names (in particular theorem names) have the mandatory
  1803 qualifier 'add'.  Previous theorem names are redeclared for
  1804 compatibility.
  1805 
  1806 * Structure "int_ring" is now an abbreviation (previously a
  1807 definition).  This fits more natural with advanced interpretations.
  1808 
  1809 
  1810 *** HOLCF ***
  1811 
  1812 * The domain package now runs in definitional mode by default: The
  1813 former command 'new_domain' is now called 'domain'.  To use the domain
  1814 package in its original axiomatic mode, use 'domain (unsafe)'.
  1815 INCOMPATIBILITY.
  1816 
  1817 * The new class "domain" is now the default sort.  Class "predomain"
  1818 is an unpointed version of "domain". Theories can be updated by
  1819 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1820 
  1821   'a::type ~> 'a::countable
  1822   'a::cpo  ~> 'a::predomain
  1823   'a::pcpo ~> 'a::domain
  1824 
  1825 * The old type class "rep" has been superseded by class "domain".
  1826 Accordingly, users of the definitional package must remove any
  1827 "default_sort rep" declarations.  INCOMPATIBILITY.
  1828 
  1829 * The domain package (definitional mode) now supports unpointed
  1830 predomain argument types, as long as they are marked 'lazy'. (Strict
  1831 arguments must be in class "domain".) For example, the following
  1832 domain definition now works:
  1833 
  1834   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1835 
  1836 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1837 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1838 'a option, and 'a list.  Additionally, it configures fixrec and the
  1839 domain package to work with these types.  For example:
  1840 
  1841   fixrec isInl :: "('a + 'b) u -> tr"
  1842     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1843 
  1844   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1845 
  1846 * The "(permissive)" option of fixrec has been replaced with a
  1847 per-equation "(unchecked)" option. See
  1848 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1849 
  1850 * The "bifinite" class no longer fixes a constant "approx"; the class
  1851 now just asserts that such a function exists.  INCOMPATIBILITY.
  1852 
  1853 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1854 defines an embedding of type 'a defl into udom by default; instances
  1855 of "bifinite" and "domain" classes are available in
  1856 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1857 
  1858 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1859 
  1860 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1861 
  1862 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1863 
  1864 * The function "cprod_map" has been renamed to "prod_map".
  1865 INCOMPATIBILITY.
  1866 
  1867 * The monadic bind operator on each powerdomain has new binder syntax
  1868 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1869 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1870 
  1871 * The infix syntax for binary union on each powerdomain has changed
  1872 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1873 syntax.  INCOMPATIBILITY.
  1874 
  1875 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1876 still supported as an input translation.
  1877 
  1878 * Renamed some theorems (the original names are also still available).
  1879 
  1880   expand_fun_below   ~> fun_below_iff
  1881   below_fun_ext      ~> fun_belowI
  1882   expand_cfun_eq     ~> cfun_eq_iff
  1883   ext_cfun           ~> cfun_eqI
  1884   expand_cfun_below  ~> cfun_below_iff
  1885   below_cfun_ext     ~> cfun_belowI
  1886   cont2cont_Rep_CFun ~> cont2cont_APP
  1887 
  1888 * The Abs and Rep functions for various types have changed names.
  1889 Related theorem names have also changed to match. INCOMPATIBILITY.
  1890 
  1891   Rep_CFun  ~> Rep_cfun
  1892   Abs_CFun  ~> Abs_cfun
  1893   Rep_Sprod ~> Rep_sprod
  1894   Abs_Sprod ~> Abs_sprod
  1895   Rep_Ssum  ~> Rep_ssum
  1896   Abs_Ssum  ~> Abs_ssum
  1897 
  1898 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1899 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1900 
  1901 * Various changes to bisimulation/coinduction with domain package:
  1902 
  1903   - Definitions of "bisim" constants no longer mention definedness.
  1904   - With mutual recursion, "bisim" predicate is now curried.
  1905   - With mutual recursion, each type gets a separate coind theorem.
  1906   - Variable names in bisim_def and coinduct rules have changed.
  1907 
  1908 INCOMPATIBILITY.
  1909 
  1910 * Case combinators generated by the domain package for type "foo" are
  1911 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1912 
  1913 * Several theorems have been renamed to more accurately reflect the
  1914 names of constants and types involved.  INCOMPATIBILITY.
  1915 
  1916   thelub_const    ~> lub_const
  1917   lub_const       ~> is_lub_const
  1918   thelubI         ~> lub_eqI
  1919   is_lub_lub      ~> is_lubD2
  1920   lubI            ~> is_lub_lub
  1921   unique_lub      ~> is_lub_unique
  1922   is_ub_lub       ~> is_lub_rangeD1
  1923   lub_bin_chain   ~> is_lub_bin_chain
  1924   lub_fun         ~> is_lub_fun
  1925   thelub_fun      ~> lub_fun
  1926   thelub_cfun     ~> lub_cfun
  1927   thelub_Pair     ~> lub_Pair
  1928   lub_cprod       ~> is_lub_prod
  1929   thelub_cprod    ~> lub_prod
  1930   minimal_cprod   ~> minimal_prod
  1931   inst_cprod_pcpo ~> inst_prod_pcpo
  1932   UU_I            ~> bottomI
  1933   compact_UU      ~> compact_bottom
  1934   deflation_UU    ~> deflation_bottom
  1935   finite_deflation_UU ~> finite_deflation_bottom
  1936 
  1937 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1938 
  1939   sq_ord_less_eq_trans ~> below_eq_trans
  1940   sq_ord_eq_less_trans ~> eq_below_trans
  1941   refl_less            ~> below_refl
  1942   trans_less           ~> below_trans
  1943   antisym_less         ~> below_antisym
  1944   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1945   box_less             ~> box_below
  1946   rev_trans_less       ~> rev_below_trans
  1947   not_less2not_eq      ~> not_below2not_eq
  1948   less_UU_iff          ~> below_UU_iff
  1949   flat_less_iff        ~> flat_below_iff
  1950   adm_less             ~> adm_below
  1951   adm_not_less         ~> adm_not_below
  1952   adm_compact_not_less ~> adm_compact_not_below
  1953   less_fun_def         ~> below_fun_def
  1954   expand_fun_less      ~> fun_below_iff
  1955   less_fun_ext         ~> fun_belowI
  1956   less_discr_def       ~> below_discr_def
  1957   discr_less_eq        ~> discr_below_eq
  1958   less_unit_def        ~> below_unit_def
  1959   less_cprod_def       ~> below_prod_def
  1960   prod_lessI           ~> prod_belowI
  1961   Pair_less_iff        ~> Pair_below_iff
  1962   fst_less_iff         ~> fst_below_iff
  1963   snd_less_iff         ~> snd_below_iff
  1964   expand_cfun_less     ~> cfun_below_iff
  1965   less_cfun_ext        ~> cfun_belowI
  1966   injection_less       ~> injection_below
  1967   less_up_def          ~> below_up_def
  1968   not_Iup_less         ~> not_Iup_below
  1969   Iup_less             ~> Iup_below
  1970   up_less              ~> up_below
  1971   Def_inject_less_eq   ~> Def_below_Def
  1972   Def_less_is_eq       ~> Def_below_iff
  1973   spair_less_iff       ~> spair_below_iff
  1974   less_sprod           ~> below_sprod
  1975   spair_less           ~> spair_below
  1976   sfst_less_iff        ~> sfst_below_iff
  1977   ssnd_less_iff        ~> ssnd_below_iff
  1978   fix_least_less       ~> fix_least_below
  1979   dist_less_one        ~> dist_below_one
  1980   less_ONE             ~> below_ONE
  1981   ONE_less_iff         ~> ONE_below_iff
  1982   less_sinlD           ~> below_sinlD
  1983   less_sinrD           ~> below_sinrD
  1984 
  1985 
  1986 *** FOL and ZF ***
  1987 
  1988 * All constant names are now qualified internally and use proper
  1989 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1990 
  1991 
  1992 *** ML ***
  1993 
  1994 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1995 Fail if the argument is false.  Due to inlining the source position of
  1996 failed assertions is included in the error output.
  1997 
  1998 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1999 text is in practice always evaluated with a stable theory checkpoint.
  2000 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  2001 
  2002 * Antiquotation @{theory A} refers to theory A from the ancestry of
  2003 the current context, not any accidental theory loader state as before.
  2004 Potential INCOMPATIBILITY, subtle change in semantics.
  2005 
  2006 * Syntax.pretty_priority (default 0) configures the required priority
  2007 of pretty-printed output and thus affects insertion of parentheses.
  2008 
  2009 * Syntax.default_root (default "any") configures the inner syntax
  2010 category (nonterminal symbol) for parsing of terms.
  2011 
  2012 * Former exception Library.UnequalLengths now coincides with
  2013 ListPair.UnequalLengths.
  2014 
  2015 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  2016 main functionality is provided by structure Simplifier.
  2017 
  2018 * Renamed raw "explode" function to "raw_explode" to emphasize its
  2019 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  2020 almost all situations.
  2021 
  2022 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  2023 See implementation manual for further details on exceptions in
  2024 Isabelle/ML.
  2025 
  2026 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  2027 meaning.
  2028 
  2029 * Renamed structure PureThy to Pure_Thy and moved most of its
  2030 operations to structure Global_Theory, to emphasize that this is
  2031 rarely-used global-only stuff.
  2032 
  2033 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  2034 instead (or tracing for high-volume output).
  2035 
  2036 * Configuration option show_question_marks only affects regular pretty
  2037 printing of types and terms, not raw Term.string_of_vname.
  2038 
  2039 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  2040 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  2041 @{thms} for most purposes.
  2042 
  2043 * ML structure Unsynchronized is never opened, not even in Isar
  2044 interaction mode as before.  Old Unsynchronized.set etc. have been
  2045 discontinued -- use plain := instead.  This should be *rare* anyway,
  2046 since modern tools always work via official context data, notably
  2047 configuration options.
  2048 
  2049 * Parallel and asynchronous execution requires special care concerning
  2050 interrupts.  Structure Exn provides some convenience functions that
  2051 avoid working directly with raw Interrupt.  User code must not absorb
  2052 interrupts -- intermediate handling (for cleanup etc.) needs to be
  2053 followed by re-raising of the original exception.  Another common
  2054 source of mistakes are "handle _" patterns, which make the meaning of
  2055 the program subject to physical effects of the environment.
  2056 
  2057 
  2058 
  2059 New in Isabelle2009-2 (June 2010)
  2060 ---------------------------------
  2061 
  2062 *** General ***
  2063 
  2064 * Authentic syntax for *all* logical entities (type classes, type
  2065 constructors, term constants): provides simple and robust
  2066 correspondence between formal entities and concrete syntax.  Within
  2067 the parse tree / AST representations, "constants" are decorated by
  2068 their category (class, type, const) and spelled out explicitly with
  2069 their full internal name.
  2070 
  2071 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  2072 and translations (translation rules and translation functions in ML).
  2073 Some hints on upgrading:
  2074 
  2075   - Many existing uses of 'syntax' and 'translations' can be replaced
  2076     by more modern 'type_notation', 'notation' and 'abbreviation',
  2077     which are independent of this issue.
  2078 
  2079   - 'translations' require markup within the AST; the term syntax
  2080     provides the following special forms:
  2081 
  2082       CONST c   -- produces syntax version of constant c from context
  2083       XCONST c  -- literally c, checked as constant from context
  2084       c         -- literally c, if declared by 'syntax'
  2085 
  2086     Plain identifiers are treated as AST variables -- occasionally the
  2087     system indicates accidental variables via the error "rhs contains
  2088     extra variables".
  2089 
  2090     Type classes and type constructors are marked according to their
  2091     concrete syntax.  Some old translations rules need to be written
  2092     for the "type" category, using type constructor application
  2093     instead of pseudo-term application of the default category
  2094     "logic".
  2095 
  2096   - 'parse_translation' etc. in ML may use the following
  2097     antiquotations:
  2098 
  2099       @{class_syntax c}   -- type class c within parse tree / AST
  2100       @{term_syntax c}    -- type constructor c within parse tree / AST
  2101       @{const_syntax c}   -- ML version of "CONST c" above
  2102       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  2103 
  2104   - Literal types within 'typed_print_translations', i.e. those *not*
  2105     represented as pseudo-terms are represented verbatim.  Use @{class
  2106     c} or @{type_name c} here instead of the above syntax
  2107     antiquotations.
  2108 
  2109 Note that old non-authentic syntax was based on unqualified base
  2110 names, so all of the above "constant" names would coincide.  Recall
  2111 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  2112 diagnose syntax problems.
  2113 
  2114 * Type constructors admit general mixfix syntax, not just infix.
  2115 
  2116 * Concrete syntax may be attached to local entities without a proof
  2117 body, too.  This works via regular mixfix annotations for 'fix',
  2118 'def', 'obtain' etc. or via the explicit 'write' command, which is
  2119 similar to the 'notation' command in theory specifications.
  2120 
  2121 * Discontinued unnamed infix syntax (legacy feature for many years) --
  2122 need to specify constant name and syntax separately.  Internal ML
  2123 datatype constructors have been renamed from InfixName to Infix etc.
  2124 Minor INCOMPATIBILITY.
  2125 
  2126 * Schematic theorem statements need to be explicitly markup as such,
  2127 via commands 'schematic_lemma', 'schematic_theorem',
  2128 'schematic_corollary'.  Thus the relevance of the proof is made
  2129 syntactically clear, which impacts performance in a parallel or
  2130 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  2131 
  2132 * Use of cumulative prems via "!" in some proof methods has been
  2133 discontinued (old legacy feature).
  2134 
  2135 * References 'trace_simp' and 'debug_simp' have been replaced by
  2136 configuration options stored in the context. Enabling tracing (the
  2137 case of debugging is similar) in proofs works via
  2138 
  2139   using [[trace_simp = true]]
  2140 
  2141 Tracing is then active for all invocations of the simplifier in
  2142 subsequent goal refinement steps. Tracing may also still be enabled or
  2143 disabled via the ProofGeneral settings menu.
  2144 
  2145 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  2146 'hide_fact' replace the former 'hide' KIND command.  Minor
  2147 INCOMPATIBILITY.
  2148 
  2149 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  2150 more efficient than combinations with -q1 or -q2.
  2151 
  2152 
  2153 *** Pure ***
  2154 
  2155 * Proofterms record type-class reasoning explicitly, using the
  2156 "unconstrain" operation internally.  This eliminates all sort
  2157 constraints from a theorem and proof, introducing explicit
  2158 OFCLASS-premises.  On the proof term level, this operation is
  2159 automatically applied at theorem boundaries, such that closed proofs
  2160 are always free of sort constraints.  INCOMPATIBILITY for tools that
  2161 inspect proof terms.
  2162 
  2163 * Local theory specifications may depend on extra type variables that
  2164 are not present in the result type -- arguments TYPE('a) :: 'a itself
  2165 are added internally.  For example:
  2166 
  2167   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  2168 
  2169 * Predicates of locales introduced by classes carry a mandatory
  2170 "class" prefix.  INCOMPATIBILITY.
  2171 
  2172 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  2173 
  2174 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  2175 'class' instead.
  2176 
  2177 * Command 'code_reflect' allows to incorporate generated ML code into
  2178 runtime environment; replaces immature code_datatype antiquotation.
  2179 INCOMPATIBILITY.
  2180 
  2181 * Code generator: simple concept for abstract datatypes obeying
  2182 invariants.
  2183 
  2184 * Code generator: details of internal data cache have no impact on the
  2185 user space functionality any longer.
  2186 
  2187 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  2188 subgoals.  This is more appropriate for interpretations with 'where'.
  2189 INCOMPATIBILITY.
  2190 
  2191 * Command 'example_proof' opens an empty proof body.  This allows to
  2192 experiment with Isar, without producing any persistent result.
  2193 
  2194 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  2195 within a local theory context, with explicit checking of the
  2196 constructors involved (in contrast to the raw 'syntax' versions).
  2197 
  2198 * Commands 'types' and 'typedecl' now work within a local theory
  2199 context -- without introducing dependencies on parameters or
  2200 assumptions, which is not possible in Isabelle/Pure.
  2201 
  2202 * Command 'defaultsort' has been renamed to 'default_sort', it works
  2203 within a local theory context.  Minor INCOMPATIBILITY.
  2204 
  2205 
  2206 *** HOL ***
  2207 
  2208 * Command 'typedef' now works within a local theory context -- without
  2209 introducing dependencies on parameters or assumptions, which is not
  2210 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  2211 contain multiple interpretations of local typedefs (with different
  2212 non-emptiness proofs), even in a global theory context.
  2213 
  2214 * New package for quotient types.  Commands 'quotient_type' and
  2215 'quotient_definition' may be used for defining types and constants by
  2216 quotient constructions.  An example is the type of integers created by
  2217 quotienting pairs of natural numbers:
  2218 
  2219   fun
  2220     intrel :: "(nat * nat) => (nat * nat) => bool"
  2221   where
  2222     "intrel (x, y) (u, v) = (x + v = u + y)"
  2223 
  2224   quotient_type int = "nat * nat" / intrel
  2225     by (auto simp add: equivp_def expand_fun_eq)
  2226 
  2227   quotient_definition
  2228     "0::int" is "(0::nat, 0::nat)"
  2229 
  2230 The method "lifting" can be used to lift of theorems from the
  2231 underlying "raw" type to the quotient type.  The example
  2232 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  2233 construction and provides a reasoning infrastructure for finite sets.
  2234 
  2235 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  2236 clash with new theory Quotient in Main HOL.
  2237 
  2238 * Moved the SMT binding into the main HOL session, eliminating
  2239 separate HOL-SMT session.
  2240 
  2241 * List membership infix mem operation is only an input abbreviation.
  2242 INCOMPATIBILITY.
  2243 
  2244 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  2245 for future developements; former Library/Word.thy is still present in
  2246 the AFP entry RSAPPS.
  2247 
  2248 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  2249 longer shadowed.  INCOMPATIBILITY.
  2250 
  2251 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  2252 INCOMPATIBILITY.
  2253 
  2254 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  2255 INCOMPATIBILITY.
  2256 
  2257 * Dropped normalizing_semiring etc; use the facts in semiring classes
  2258 instead.  INCOMPATIBILITY.
  2259 
  2260 * Dropped several real-specific versions of lemmas about floor and
  2261 ceiling; use the generic lemmas from theory "Archimedean_Field"
  2262 instead.  INCOMPATIBILITY.
  2263 
  2264   floor_number_of_eq         ~> floor_number_of
  2265   le_floor_eq_number_of      ~> number_of_le_floor
  2266   le_floor_eq_zero           ~> zero_le_floor
  2267   le_floor_eq_one            ~> one_le_floor
  2268   floor_less_eq_number_of    ~> floor_less_number_of
  2269   floor_less_eq_zero         ~> floor_less_zero
  2270   floor_less_eq_one          ~> floor_less_one
  2271   less_floor_eq_number_of    ~> number_of_less_floor
  2272   less_floor_eq_zero         ~> zero_less_floor
  2273   less_floor_eq_one          ~> one_less_floor
  2274   floor_le_eq_number_of      ~> floor_le_number_of
  2275   floor_le_eq_zero           ~> floor_le_zero
  2276   floor_le_eq_one            ~> floor_le_one
  2277   floor_subtract_number_of   ~> floor_diff_number_of
  2278   floor_subtract_one         ~> floor_diff_one
  2279   ceiling_number_of_eq       ~> ceiling_number_of
  2280   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  2281   ceiling_le_zero_eq         ~> ceiling_le_zero
  2282   ceiling_le_eq_one          ~> ceiling_le_one
  2283   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  2284   less_ceiling_eq_zero       ~> zero_less_ceiling
  2285   less_ceiling_eq_one        ~> one_less_ceiling
  2286   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  2287   ceiling_less_eq_zero       ~> ceiling_less_zero
  2288   ceiling_less_eq_one        ~> ceiling_less_one
  2289   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  2290   le_ceiling_eq_zero         ~> zero_le_ceiling
  2291   le_ceiling_eq_one          ~> one_le_ceiling
  2292   ceiling_subtract_number_of ~> ceiling_diff_number_of
  2293   ceiling_subtract_one       ~> ceiling_diff_one
  2294 
  2295 * Theory "Finite_Set": various folding_XXX locales facilitate the
  2296 application of the various fold combinators on finite sets.
  2297 
  2298 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  2299 provides abstract red-black tree type which is backed by "RBT_Impl" as
  2300 implementation.  INCOMPATIBILTY.
  2301 
  2302 * Theory Library/Coinductive_List has been removed -- superseded by
  2303 AFP/thys/Coinductive.
  2304 
  2305 * Theory PReal, including the type "preal" and related operations, has
  2306 been removed.  INCOMPATIBILITY.
  2307 
  2308 * Real: new development using Cauchy Sequences.
  2309 
  2310 * Split off theory "Big_Operators" containing setsum, setprod,
  2311 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  2312 
  2313 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  2314 "Int" etc.  INCOMPATIBILITY.
  2315 
  2316 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  2317 
  2318 * New set of rules "ac_simps" provides combined assoc / commute
  2319 rewrites for all interpretations of the appropriate generic locales.
  2320 
  2321 * Renamed theory "OrderedGroup" to "Groups" and split theory
  2322 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  2323 appropriate and more consistent names suitable for name prefixes
  2324 within the HOL theories.  INCOMPATIBILITY.
  2325 
  2326 * Some generic constants have been put to appropriate theories:
  2327   - less_eq, less: Orderings
  2328   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  2329   - inverse, divide: Rings
  2330 INCOMPATIBILITY.
  2331 
  2332 * More consistent naming of type classes involving orderings (and
  2333 lattices):
  2334 
  2335     lower_semilattice                   ~> semilattice_inf
  2336     upper_semilattice                   ~> semilattice_sup
  2337 
  2338     dense_linear_order                  ~> dense_linorder
  2339 
  2340     pordered_ab_group_add               ~> ordered_ab_group_add
  2341     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  2342     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  2343     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  2344     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  2345     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  2346     pordered_cancel_semiring            ~> ordered_cancel_semiring
  2347     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  2348     pordered_comm_ring                  ~> ordered_comm_ring
  2349     pordered_comm_semiring              ~> ordered_comm_semiring
  2350     pordered_ring                       ~> ordered_ring
  2351     pordered_ring_abs                   ~> ordered_ring_abs
  2352     pordered_semiring                   ~> ordered_semiring
  2353 
  2354     ordered_ab_group_add                ~> linordered_ab_group_add
  2355     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  2356     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  2357     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  2358     ordered_field                       ~> linordered_field
  2359     ordered_field_no_lb                 ~> linordered_field_no_lb
  2360     ordered_field_no_ub                 ~> linordered_field_no_ub
  2361     ordered_field_dense_linear_order    ~> dense_linordered_field
  2362     ordered_idom                        ~> linordered_idom
  2363     ordered_ring                        ~> linordered_ring
  2364     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  2365     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  2366     ordered_ring_strict                 ~> linordered_ring_strict
  2367     ordered_semidom                     ~> linordered_semidom
  2368     ordered_semiring                    ~> linordered_semiring
  2369     ordered_semiring_1                  ~> linordered_semiring_1
  2370     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  2371     ordered_semiring_strict             ~> linordered_semiring_strict
  2372 
  2373   The following slightly odd type classes have been moved to a
  2374   separate theory Library/Lattice_Algebras:
  2375 
  2376     lordered_ab_group_add               ~> lattice_ab_group_add
  2377     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  2378     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  2379     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  2380     lordered_ring                       ~> lattice_ring
  2381 
  2382 INCOMPATIBILITY.
  2383 
  2384 * Refined field classes:
  2385   - classes division_ring_inverse_zero, field_inverse_zero,
  2386     linordered_field_inverse_zero include rule inverse 0 = 0 --
  2387     subsumes former division_by_zero class;
  2388   - numerous lemmas have been ported from field to division_ring.
  2389 INCOMPATIBILITY.
  2390 
  2391 * Refined algebra theorem collections:
  2392   - dropped theorem group group_simps, use algebra_simps instead;
  2393   - dropped theorem group ring_simps, use field_simps instead;
  2394   - proper theorem collection field_simps subsumes former theorem
  2395     groups field_eq_simps and field_simps;
  2396   - dropped lemma eq_minus_self_iff which is a duplicate for
  2397     equal_neg_zero.
  2398 INCOMPATIBILITY.
  2399 
  2400 * Theory Finite_Set and List: some lemmas have been generalized from
  2401 sets to lattices:
  2402 
  2403   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  2404   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  2405   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  2406   union_Union_fold_union        ~> sup_Sup_fold_sup
  2407   Inter_fold_inter              ~> Inf_fold_inf
  2408   Union_fold_union              ~> Sup_fold_sup
  2409   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  2410   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  2411   INTER_fold_inter              ~> INFI_fold_inf
  2412   UNION_fold_union              ~> SUPR_fold_sup
  2413 
  2414 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  2415 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  2416 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  2417 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  2418 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  2419 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  2420 
  2421 * Reorganized theory Multiset: swapped notation of pointwise and
  2422 multiset order:
  2423 
  2424   - pointwise ordering is instance of class order with standard syntax
  2425     <= and <;
  2426   - multiset ordering has syntax <=# and <#; partial order properties
  2427     are provided by means of interpretation with prefix
  2428     multiset_order;
  2429   - less duplication, less historical organization of sections,
  2430     conversion from associations lists to multisets, rudimentary code
  2431     generation;
  2432   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  2433     if needed.
  2434 
  2435 Renamed:
  2436 
  2437   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  2438   multi_count_ext  ~>  multiset_ext
  2439   diff_union_inverse2  ~>  diff_union_cancelR
  2440 
  2441 INCOMPATIBILITY.
  2442 
  2443 * Theory Permutation: replaced local "remove" by List.remove1.
  2444 
  2445 * Code generation: ML and OCaml code is decorated with signatures.
  2446 
  2447 * Theory List: added transpose.
  2448 
  2449 * Library/Nat_Bijection.thy is a collection of bijective functions
  2450 between nat and other types, which supersedes the older libraries
  2451 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2452 
  2453   Constants:
  2454   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2455   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2456   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2457   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2458   Countable.pair_encode           ~> prod_encode
  2459   NatIso.prod2nat                 ~> prod_encode
  2460   NatIso.nat2prod                 ~> prod_decode
  2461   NatIso.sum2nat                  ~> sum_encode
  2462   NatIso.nat2sum                  ~> sum_decode
  2463   NatIso.list2nat                 ~> list_encode
  2464   NatIso.nat2list                 ~> list_decode
  2465   NatIso.set2nat                  ~> set_encode
  2466   NatIso.nat2set                  ~> set_decode
  2467 
  2468   Lemmas:
  2469   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2470   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2471   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2472   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2473   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2474   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2475   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2476   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2477   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2478   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2479   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2480   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2481   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2482 
  2483 * Sledgehammer:
  2484   - Renamed ATP commands:
  2485     atp_info     ~> sledgehammer running_atps
  2486     atp_kill     ~> sledgehammer kill_atps
  2487     atp_messages ~> sledgehammer messages
  2488     atp_minimize ~> sledgehammer minimize
  2489     print_atps   ~> sledgehammer available_atps
  2490     INCOMPATIBILITY.
  2491   - Added user's manual ("isabelle doc sledgehammer").
  2492   - Added option syntax and "sledgehammer_params" to customize
  2493     Sledgehammer's behavior.  See the manual for details.
  2494   - Modified the Isar proof reconstruction code so that it produces
  2495     direct proofs rather than proofs by contradiction.  (This feature
  2496     is still experimental.)
  2497   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2498     full-typed mode.
  2499   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2500 
  2501 * Nitpick:
  2502   - Added and implemented "binary_ints" and "bits" options.
  2503   - Added "std" option and implemented support for nonstandard models.
  2504   - Added and implemented "finitize" option to improve the precision
  2505     of infinite datatypes based on a monotonicity analysis.
  2506   - Added support for quotient types.
  2507   - Added support for "specification" and "ax_specification"
  2508     constructs.
  2509   - Added support for local definitions (for "function" and
  2510     "termination" proofs).
  2511   - Added support for term postprocessors.
  2512   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2513   - Improved efficiency of "destroy_constrs" optimization.
  2514   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2515     record getters.
  2516   - Fixed soundness bug related to higher-order constructors.
  2517   - Fixed soundness bug when "full_descrs" is enabled.
  2518   - Improved precision of set constructs.
  2519   - Added "atoms" option.
  2520   - Added cache to speed up repeated Kodkod invocations on the same
  2521     problems.
  2522   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2523     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2524     "SAT4J_Light".  INCOMPATIBILITY.
  2525   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2526     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2527   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2528 
  2529 * Method "induct" now takes instantiations of the form t, where t is not
  2530   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2531   If this is not intended, t has to be enclosed in parentheses.
  2532   By default, the equalities generated by definitional instantiations
  2533   are pre-simplified, which may cause parameters of inductive cases
  2534   to disappear, or may even delete some of the inductive cases.
  2535   Use "induct (no_simp)" instead of "induct" to restore the old
  2536   behaviour. The (no_simp) option is also understood by the "cases"
  2537   and "nominal_induct" methods, which now perform pre-simplification, too.
  2538   INCOMPATIBILITY.
  2539 
  2540 
  2541 *** HOLCF ***
  2542 
  2543 * Variable names in lemmas generated by the domain package have
  2544 changed; the naming scheme is now consistent with the HOL datatype
  2545 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2546 
  2547 * The domain package no longer defines the function "foo_copy" for
  2548 recursive domain "foo".  The reach lemma is now stated directly in
  2549 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2550 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2551 
  2552 * Most definedness lemmas generated by the domain package (previously
  2553 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2554 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2555 Proofs that used definedness lemmas as intro rules may break,
  2556 potential INCOMPATIBILITY.
  2557 
  2558 * Induction and casedist rules generated by the domain package now
  2559 declare proper case_names (one called "bottom", and one named for each
  2560 constructor).  INCOMPATIBILITY.
  2561 
  2562 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2563 rules are generated for each domain, INCOMPATIBILITY.
  2564 
  2565   foo_bar.reach       ~> foo.reach  bar.reach
  2566   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2567 
  2568 * Some lemmas generated by the domain package have been renamed for
  2569 consistency with the datatype package, INCOMPATIBILITY.
  2570 
  2571   foo.ind        ~> foo.induct
  2572   foo.finite_ind ~> foo.finite_induct
  2573   foo.coind      ~> foo.coinduct
  2574   foo.casedist   ~> foo.exhaust
  2575   foo.exhaust    ~> foo.nchotomy
  2576 
  2577 * For consistency with other definition packages, the fixrec package
  2578 now generates qualified theorem names, INCOMPATIBILITY.
  2579 
  2580   foo_simps  ~> foo.simps
  2581   foo_unfold ~> foo.unfold
  2582   foo_induct ~> foo.induct
  2583 
  2584 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2585 method and internal fixrec proofs now use the default simpset instead.
  2586 INCOMPATIBILITY.
  2587 
  2588 * The "contlub" predicate has been removed.  Proof scripts should use
  2589 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2590 
  2591 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2592 
  2593 * The constants cpair, cfst, and csnd have been removed in favor of
  2594 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2595 
  2596 
  2597 *** ML ***
  2598 
  2599 * Antiquotations for basic formal entities:
  2600 
  2601     @{class NAME}         -- type class
  2602     @{class_syntax NAME}  -- syntax representation of the above
  2603 
  2604     @{type_name NAME}     -- logical type
  2605     @{type_abbrev NAME}   -- type abbreviation
  2606     @{nonterminal NAME}   -- type of concrete syntactic category
  2607     @{type_syntax NAME}   -- syntax representation of any of the above
  2608 
  2609     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2610     @{const_abbrev NAME}  -- abbreviated constant
  2611     @{const_syntax NAME}  -- syntax representation of any of the above
  2612 
  2613 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2614 syntax constant (cf. 'syntax' command).
  2615 
  2616 * Antiquotation @{make_string} inlines a function to print arbitrary
  2617 values similar to the ML toplevel.  The result is compiler dependent
  2618 and may fall back on "?" in certain situations.
  2619 
  2620 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2621 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2622 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2623 not work with the asynchronous Isar document model.
  2624 
  2625 * Configuration options now admit dynamic default values, depending on
  2626 the context or even global references.
  2627 
  2628 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2629 uses an efficient external library if available (for Poly/ML).
  2630 
  2631 * Renamed some important ML structures, while keeping the old names
  2632 for some time as aliases within the structure Legacy:
  2633 
  2634   OuterKeyword  ~>  Keyword
  2635   OuterLex      ~>  Token
  2636   OuterParse    ~>  Parse
  2637   OuterSyntax   ~>  Outer_Syntax
  2638   PrintMode     ~>  Print_Mode
  2639   SpecParse     ~>  Parse_Spec
  2640   ThyInfo       ~>  Thy_Info
  2641   ThyLoad       ~>  Thy_Load
  2642   ThyOutput     ~>  Thy_Output
  2643   TypeInfer     ~>  Type_Infer
  2644 
  2645 Note that "open Legacy" simplifies porting of sources, but forgetting
  2646 to remove it again will complicate porting again in the future.
  2647 
  2648 * Most operations that refer to a global context are named
  2649 accordingly, e.g. Simplifier.global_context or
  2650 ProofContext.init_global.  There are some situations where a global
  2651 context actually works, but under normal circumstances one needs to
  2652 pass the proper local context through the code!
  2653 
  2654 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2655 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2656 Pretty.pp argument to merge, which is absent in the standard
  2657 Theory_Data version.
  2658 
  2659 * Sorts.certify_sort and derived "cert" operations for types and terms
  2660 no longer minimize sorts.  Thus certification at the boundary of the
  2661 inference kernel becomes invariant under addition of class relations,
  2662 which is an important monotonicity principle.  Sorts are now minimized
  2663 in the syntax layer only, at the boundary between the end-user and the
  2664 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2665 explicitly in rare situations.
  2666 
  2667 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2668 emphasize that this is in no way a standard operation.
  2669 INCOMPATIBILITY.
  2670 
  2671 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2672 usual for resolution.  Rare INCOMPATIBILITY.
  2673 
  2674 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2675 to emphasize that these only work in a global situation (which is
  2676 quite rare).
  2677 
  2678 * Curried take and drop in library.ML; negative length is interpreted
  2679 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2680 
  2681 * Proof terms: type substitutions on proof constants now use canonical
  2682 order of type variables.  INCOMPATIBILITY for tools working with proof
  2683 terms.
  2684 
  2685 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2686 may no longer carry premises.  User-level specifications are
  2687 transformed accordingly by Thm.add_axiom/add_def.
  2688 
  2689 
  2690 *** System ***
  2691 
  2692 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2693 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2694 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2695 
  2696 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2697 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2698 respectively.
  2699 
  2700 * Old lib/scripts/polyml-platform is superseded by the
  2701 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2702 variant, even on a 64 bit machine.  The following example setting
  2703 prefers 64 bit if available:
  2704 
  2705   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2706 
  2707 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2708 Isabelle/Scala layer for advanced prover interaction and integration.
  2709 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2710 component.
  2711 
  2712 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2713 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2714 similar to the default assignment of the document preparation system
  2715 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2716 provides some operations for direct access to the font without asking
  2717 the user for manual installation.
  2718 
  2719 
  2720 
  2721 New in Isabelle2009-1 (December 2009)
  2722 -------------------------------------
  2723 
  2724 *** General ***
  2725 
  2726 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2727 one backslash should be used, even in ML sources.
  2728 
  2729 
  2730 *** Pure ***
  2731 
  2732 * Locale interpretation propagates mixins along the locale hierarchy.
  2733 The currently only available mixins are the equations used to map
  2734 local definitions to terms of the target domain of an interpretation.
  2735 
  2736 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2737 loc" to print all interpretations of locale "loc" in the theory.
  2738 Interpretations in proofs are not shown.
  2739 
  2740 * Thoroughly revised locales tutorial.  New section on conditional
  2741 interpretation.
  2742 
  2743 * On instantiation of classes, remaining undefined class parameters
  2744 are formally declared.  INCOMPATIBILITY.
  2745 
  2746 
  2747 *** Document preparation ***
  2748 
  2749 * New generalized style concept for printing terms: @{foo (style) ...}
  2750 instead of @{foo_style style ...}  (old form is still retained for
  2751 backward compatibility).  Styles can be also applied for
  2752 antiquotations prop, term_type and typeof.
  2753 
  2754 
  2755 *** HOL ***
  2756 
  2757 * New proof method "smt" for a combination of first-order logic with
  2758 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2759 fixed-size bitvectors; there is also basic support for higher-order
  2760 features (esp. lambda abstractions).  It is an incomplete decision
  2761 procedure based on external SMT solvers using the oracle mechanism;
  2762 for the SMT solver Z3, this method is proof-producing.  Certificates
  2763 are provided to avoid calling the external solvers solely for
  2764 re-checking proofs.  Due to a remote SMT service there is no need for
  2765 installing SMT solvers locally.  See src/HOL/SMT.
  2766 
  2767 * New commands to load and prove verification conditions generated by
  2768 the Boogie program verifier or derived systems (e.g. the Verifying C
  2769 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2770 
  2771 * New counterexample generator tool 'nitpick' based on the Kodkod
  2772 relational model finder.  See src/HOL/Tools/Nitpick and
  2773 src/HOL/Nitpick_Examples.
  2774 
  2775 * New commands 'code_pred' and 'values' to invoke the predicate
  2776 compiler and to enumerate values of inductive predicates.
  2777 
  2778 * A tabled implementation of the reflexive transitive closure.
  2779 
  2780 * New implementation of quickcheck uses generic code generator;
  2781 default generators are provided for all suitable HOL types, records
  2782 and datatypes.  Old quickcheck can be re-activated importing theory
  2783 Library/SML_Quickcheck.
  2784 
  2785 * New testing tool Mirabelle for automated proof tools.  Applies
  2786 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2787 every proof step in a theory.  To be used in batch mode via the
  2788 "mirabelle" utility.
  2789 
  2790 * New proof method "sos" (sum of squares) for nonlinear real
  2791 arithmetic (originally due to John Harison). It requires theory
  2792 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2793 works well in practice on quantifier-free real arithmetic with +, -,
  2794 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2795 inequalities between polynomials.  It makes use of external
  2796 semidefinite programming solvers.  Method "sos" generates a
  2797 certificate that can be pasted into the proof thus avoiding the need
  2798 to call an external tool every time the proof is checked.  See
  2799 src/HOL/Library/Sum_Of_Squares.
  2800 
  2801 * New method "linarith" invokes existing linear arithmetic decision
  2802 procedure only.
  2803 
  2804 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2805 
  2806 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2807 Causes full type information to be output to the ATPs.  This slows
  2808 ATPs down considerably but eliminates a source of unsound "proofs"
  2809 that fail later.
  2810 
  2811 * New method "metisFT": A version of metis that uses full type
  2812 information in order to avoid failures of proof reconstruction.
  2813 
  2814 * New evaluator "approximate" approximates an real valued term using
  2815 the same method as the approximation method.
  2816 
  2817 * Method "approximate" now supports arithmetic expressions as
  2818 boundaries of intervals and implements interval splitting and Taylor
  2819 series expansion.
  2820 
  2821 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2822 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2823 
  2824 * New theory SupInf of the supremum and infimum operators for sets of
  2825 reals.
  2826 
  2827 * New theory Probability, which contains a development of measure
  2828 theory, eventually leading to Lebesgue integration and probability.
  2829 
  2830 * Extended Multivariate Analysis to include derivation and Brouwer's
  2831 fixpoint theorem.
  2832 
  2833 * Reorganization of number theory, INCOMPATIBILITY:
  2834   - new number theory development for nat and int, in theories Divides
  2835     and GCD as well as in new session Number_Theory
  2836   - some constants and facts now suffixed with _nat and _int
  2837     accordingly
  2838   - former session NumberTheory now named Old_Number_Theory, including
  2839     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2840   - moved theory Pocklington from src/HOL/Library to
  2841     src/HOL/Old_Number_Theory
  2842 
  2843 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2844 lcm of finite and infinite sets. It is shown that they form a complete
  2845 lattice.
  2846 
  2847 * Class semiring_div requires superclass no_zero_divisors and proof of
  2848 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2849 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2850 generalized to class semiring_div, subsuming former theorems
  2851 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2852 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2853 INCOMPATIBILITY.
  2854 
  2855 * Refinements to lattice classes and sets:
  2856   - less default intro/elim rules in locale variant, more default
  2857     intro/elim rules in class variant: more uniformity
  2858   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2859     le_inf_iff
  2860   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2861     sup_aci)
  2862   - renamed ACI to inf_sup_aci
  2863   - new class "boolean_algebra"
  2864   - class "complete_lattice" moved to separate theory
  2865     "Complete_Lattice"; corresponding constants (and abbreviations)
  2866     renamed and with authentic syntax:
  2867     Set.Inf ~>    Complete_Lattice.Inf
  2868     Set.Sup ~>    Complete_Lattice.Sup
  2869     Set.INFI ~>   Complete_Lattice.INFI
  2870     Set.SUPR ~>   Complete_Lattice.SUPR
  2871     Set.Inter ~>  Complete_Lattice.Inter
  2872     Set.Union ~>  Complete_Lattice.Union
  2873     Set.INTER ~>  Complete_Lattice.INTER
  2874     Set.UNION ~>  Complete_Lattice.UNION
  2875   - authentic syntax for
  2876     Set.Pow
  2877     Set.image
  2878   - mere abbreviations:
  2879     Set.empty               (for bot)
  2880     Set.UNIV                (for top)
  2881     Set.inter               (for inf, formerly Set.Int)
  2882     Set.union               (for sup, formerly Set.Un)
  2883     Complete_Lattice.Inter  (for Inf)
  2884     Complete_Lattice.Union  (for Sup)
  2885     Complete_Lattice.INTER  (for INFI)
  2886     Complete_Lattice.UNION  (for SUPR)
  2887   - object-logic definitions as far as appropriate
  2888 
  2889 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2890 Un_subset_iff are explicitly deleted as default simp rules; then also
  2891 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2892 deleted to achieve the desired effect.
  2893 
  2894 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2895 rules by default any longer; the same applies to min_max.inf_absorb1
  2896 etc.  INCOMPATIBILITY.
  2897 
  2898 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2899 pred_set_conv by default.  INCOMPATIBILITY.
  2900 
  2901 * Power operations on relations and functions are now one dedicated
  2902 constant "compow" with infix syntax "^^".  Power operation on
  2903 multiplicative monoids retains syntax "^" and is now defined generic
  2904 in class power.  INCOMPATIBILITY.
  2905 
  2906 * Relation composition "R O S" now has a more standard argument order:
  2907 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2908 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2909 break, since the O_assoc rule was not rewritten like this.  Fix using
  2910 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2911 
  2912 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2913 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2914 INCOMPATIBILITY.
  2915 
  2916 * Most rules produced by inductive and datatype package have mandatory
  2917 prefixes.  INCOMPATIBILITY.
  2918 
  2919 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2920 the attribute of the same name.  Each of the theorems in the list
  2921 DERIV_intros assumes composition with an additional function and
  2922 matches a variable to the derivative, which has to be solved by the
  2923 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2924 of most elementary terms.  Former Maclauren.DERIV_tac and
  2925 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2926 INCOMPATIBILITY.
  2927 
  2928 * Code generator attributes follow the usual underscore convention:
  2929     code_unfold     replaces    code unfold
  2930     code_post       replaces    code post
  2931     etc.
  2932   INCOMPATIBILITY.
  2933 
  2934 * Renamed methods:
  2935     sizechange -> size_change
  2936     induct_scheme -> induction_schema
  2937   INCOMPATIBILITY.
  2938 
  2939 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2940 INCOMPATIBILITY, use "undefined" directly.
  2941 
  2942 * Renamed theorems:
  2943     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2944     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2945     Suc_plus1 -> Suc_eq_plus1
  2946     *anti_sym -> *antisym*
  2947     vector_less_eq_def -> vector_le_def
  2948   INCOMPATIBILITY.
  2949 
  2950 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2951 INCOMPATIBILITY.
  2952 
  2953 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2954 INCOMPATIBILITY.
  2955 
  2956 
  2957 *** HOLCF ***
  2958 
  2959 * Theory Representable defines a class "rep" of domains that are
  2960 representable (via an ep-pair) in the universal domain type "udom".
  2961 Instances are provided for all type constructors defined in HOLCF.
  2962 
  2963 * The 'new_domain' command is a purely definitional version of the
  2964 domain package, for representable domains.  Syntax is identical to the
  2965 old domain package.  The 'new_domain' package also supports indirect
  2966 recursion using previously-defined type constructors.  See
  2967 src/HOLCF/ex/New_Domain.thy for examples.
  2968 
  2969 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2970 on the left-hand side of an equation, and then performs
  2971 simplification.  Rewriting is done using rules declared with the
  2972 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2973 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2974 
  2975 * The pattern-match compiler in 'fixrec' can now handle constructors
  2976 with HOL function types.  Pattern-match combinators for the Pair
  2977 constructor are pre-configured.
  2978 
  2979 * The 'fixrec' package now produces better fixed-point induction rules
  2980 for mutually-recursive definitions:  Induction rules have conclusions
  2981 of the form "P foo bar" instead of "P <foo, bar>".
  2982 
  2983 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2984 been renamed to "below".  The name "below" now replaces "less" in many
  2985 theorem names.  (Legacy theorem names using "less" are still supported
  2986 as well.)
  2987 
  2988 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2989 patterns can be used to generate strictness rules, or to make
  2990 functions more strict (much like the bang-patterns supported by the
  2991 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2992 examples.
  2993 
  2994 
  2995 *** ML ***
  2996 
  2997 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2998 errors and run-time exceptions, including detailed source positions.
  2999 
  3000 * Structure Name_Space (formerly NameSpace) now manages uniquely
  3001 identified entries, with some additional information such as source
  3002 position, logical grouping etc.
  3003 
  3004 * Theory and context data is now introduced by the simplified and
  3005 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  3006 to be pure, but the old TheoryDataFun for mutable data (with explicit
  3007 copy operation) is still available for some time.
  3008 
  3009 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  3010 provides a high-level programming interface to synchronized state
  3011 variables with atomic update.  This works via pure function
  3012 application within a critical section -- its runtime should be as
  3013 short as possible; beware of deadlocks if critical code is nested,
  3014 either directly or indirectly via other synchronized variables!
  3015 
  3016 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  3017 wraps raw ML references, explicitly indicating their non-thread-safe
  3018 behaviour.  The Isar toplevel keeps this structure open, to
  3019 accommodate Proof General as well as quick and dirty interactive
  3020 experiments with references.
  3021 
  3022 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  3023 parallel tactical reasoning.
  3024 
  3025 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  3026 are similar to SUBPROOF, but are slightly more flexible: only the
  3027 specified parts of the subgoal are imported into the context, and the
  3028 body tactic may introduce new subgoals and schematic variables.
  3029 
  3030 * Old tactical METAHYPS, which does not observe the proof context, has
  3031 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  3032 or Subgoal.FOCUS etc.
  3033 
  3034 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  3035 functors have their own ML name space there is no point to mark them
  3036 separately.)  Minor INCOMPATIBILITY.
  3037 
  3038 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  3039 
  3040 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  3041 INCOMPATIBILITY.
  3042 
  3043 * Operations of structure Skip_Proof no longer require quick_and_dirty
  3044 mode, which avoids critical setmp.
  3045 
  3046 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  3047 combinators for "args".  INCOMPATIBILITY, need to use simplified
  3048 Attrib/Method.setup introduced in Isabelle2009.
  3049 
  3050 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  3051 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  3052 last resort.  INCOMPATIBILITY.
  3053 
  3054 * Display.pretty_thm now requires a proper context (cf. former
  3055 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  3056 or even Display.pretty_thm_without_context as last resort.
  3057 INCOMPATIBILITY.
  3058 
  3059 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  3060 Syntax.pretty_typ/term directly, preferably with proper context
  3061 instead of global theory.
  3062 
  3063 
  3064 *** System ***
  3065 
  3066 * Further fine tuning of parallel proof checking, scales up to 8 cores
  3067 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  3068 usedir option -q.
  3069 
  3070 * Support for additional "Isabelle components" via etc/components, see
  3071 also the system manual.
  3072 
  3073 * The isabelle makeall tool now operates on all components with
  3074 IsaMakefile, not just hardwired "logics".
  3075 
  3076 * Removed "compress" option from isabelle-process and isabelle usedir;
  3077 this is always enabled.
  3078 
  3079 * Discontinued support for Poly/ML 4.x versions.
  3080 
  3081 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  3082 on a given logic image.  This requires the lighttpd webserver and is
  3083 currently supported on Linux only.
  3084 
  3085 
  3086 
  3087 New in Isabelle2009 (April 2009)
  3088 --------------------------------
  3089 
  3090 *** General ***
  3091 
  3092 * Simplified main Isabelle executables, with less surprises on
  3093 case-insensitive file-systems (such as Mac OS).
  3094 
  3095   - The main Isabelle tool wrapper is now called "isabelle" instead of
  3096     "isatool."
  3097 
  3098   - The former "isabelle" alias for "isabelle-process" has been
  3099     removed (should rarely occur to regular users).
  3100 
  3101   - The former "isabelle-interface" and its alias "Isabelle" have been
  3102     removed (interfaces are now regular Isabelle tools).
  3103 
  3104 Within scripts and make files, the Isabelle environment variables
  3105 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  3106 respectively.  (The latter are still available as legacy feature.)
  3107 
  3108 The old isabelle-interface wrapper could react in confusing ways if
  3109 the interface was uninstalled or changed otherwise.  Individual
  3110 interface tool configuration is now more explicit, see also the
  3111 Isabelle system manual.  In particular, Proof General is now available
  3112 via "isabelle emacs".
  3113 
  3114 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  3115 purge installed copies of Isabelle executables and re-run "isabelle
  3116 install -p ...", or use symlinks.
  3117 
  3118 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  3119 old ~/isabelle, which was slightly non-standard and apt to cause
  3120 surprises on case-insensitive file-systems (such as Mac OS).
  3121 
  3122 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  3123 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  3124 care is required when using older releases of Isabelle.  Note that
  3125 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  3126 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  3127 
  3128 * Proofs of fully specified statements are run in parallel on
  3129 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  3130 a regular 4-core machine, if the initial heap space is made reasonably
  3131 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  3132 
  3133 * The main reference manuals ("isar-ref", "implementation", and
  3134 "system") have been updated and extended.  Formally checked references
  3135 as hyperlinks are now available uniformly.
  3136 
  3137 
  3138 *** Pure ***
  3139 
  3140 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  3141 respects.  The most important changes are listed below.  See the
  3142 Tutorial on Locales ("locales" manual) for details.
  3143 
  3144 - In locale expressions, instantiation replaces renaming.  Parameters
  3145 must be declared in a for clause.  To aid compatibility with previous
  3146 parameter inheritance, in locale declarations, parameters that are not
  3147 'touched' (instantiation position "_" or omitted) are implicitly added
  3148 with their syntax at the beginning of the for clause.
  3149 
  3150 - Syntax from abbreviations and definitions in locales is available in
  3151 locale expressions and context elements.  The latter is particularly
  3152 useful in locale declarations.
  3153 
  3154 - More flexible mechanisms to qualify names generated by locale
  3155 expressions.  Qualifiers (prefixes) may be specified in locale
  3156 expressions, and can be marked as mandatory (syntax: "name!:") or
  3157 optional (syntax "name?:").  The default depends for plain "name:"
  3158 depends on the situation where a locale expression is used: in
  3159 commands 'locale' and 'sublocale' prefixes are optional, in
  3160 'interpretation' and 'interpret' prefixes are mandatory.  The old
  3161 implicit qualifiers derived from the parameter names of a locale are
  3162 no longer generated.
  3163 
  3164 - Command "sublocale l < e" replaces "interpretation l < e".  The
  3165 instantiation clause in "interpretation" and "interpret" (square
  3166 brackets) is no longer available.  Use locale expressions.
  3167 
  3168 - When converting proof scripts, mandatory qualifiers in
  3169 'interpretation' and 'interpret' should be retained by default, even
  3170 if this is an INCOMPATIBILITY compared to former behavior.  In the
  3171 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  3172 in locale expressions range over a single locale instance only.
  3173 
  3174 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  3175 In existing theorem specifications replace the includes element by the
  3176 respective context elements of the included locale, omitting those
  3177 that are already present in the theorem specification.  Multiple
  3178 assume elements of a locale should be replaced by a single one
  3179 involving the locale predicate.  In the proof body, declarations (most
  3180 notably theorems) may be regained by interpreting the respective
  3181 locales in the proof context as required (command "interpret").
  3182 
  3183 If using "includes" in replacement of a target solely because the
  3184 parameter types in the theorem are not as general as in the target,
  3185 consider declaring a new locale with additional type constraints on
  3186 the parameters (context element "constrains").
  3187 
  3188 - Discontinued "locale (open)".  INCOMPATIBILITY.
  3189 
  3190 - Locale interpretation commands no longer attempt to simplify goal.
  3191 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  3192 methods intro_locales and unfold_locales to clarify.
  3193 
  3194 - Locale interpretation commands no longer accept interpretation
  3195 attributes.  INCOMPATIBILITY.
  3196 
  3197 * Class declaration: so-called "base sort" must not be given in import
  3198 list any longer, but is inferred from the specification.  Particularly
  3199 in HOL, write
  3200 
  3201     class foo = ...
  3202 
  3203 instead of
  3204 
  3205     class foo = type + ...
  3206 
  3207 * Class target: global versions of theorems stemming do not carry a
  3208 parameter prefix any longer.  INCOMPATIBILITY.
  3209 
  3210 * Class 'instance' command no longer accepts attached definitions.
  3211 INCOMPATIBILITY, use proper 'instantiation' target instead.
  3212 
  3213 * Recovered hiding of consts, which was accidentally broken in
  3214 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  3215 makes c inaccessible; consider using ``hide (open) const c'' instead.
  3216 
  3217 * Slightly more coherent Pure syntax, with updated documentation in
  3218 isar-ref manual.  Removed locales meta_term_syntax and
  3219 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  3220 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  3221 directly in regular applications.
  3222 
  3223 * There is a new syntactic category "float_const" for signed decimal
  3224 fractions (e.g. 123.45 or -123.45).
  3225 
  3226 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  3227 interface with 'setup' command instead.
  3228 
  3229 * Command 'local_setup' is similar to 'setup', but operates on a local
  3230 theory context.
  3231 
  3232 * The 'axiomatization' command now only works within a global theory
  3233 context.  INCOMPATIBILITY.
  3234 
  3235 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  3236 hypotheses.  Sorts required in the course of reasoning need to be
  3237 covered by the constraints in the initial statement, completed by the
  3238 type instance information of the background theory.  Non-trivial sort
  3239 hypotheses, which rarely occur in practice, may be specified via
  3240 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  3241 
  3242   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  3243 
  3244 The result contains an implicit sort hypotheses as before --
  3245 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  3246 normalization.
  3247 
  3248 * Generalized Isar history, with support for linear undo, direct state
  3249 addressing etc.
  3250 
  3251 * Changed defaults for unify configuration options:
  3252 
  3253   unify_trace_bound = 50 (formerly 25)
  3254   unify_search_bound = 60 (formerly 30)
  3255 
  3256 * Different bookkeeping for code equations (INCOMPATIBILITY):
  3257 
  3258   a) On theory merge, the last set of code equations for a particular
  3259      constant is taken (in accordance with the policy applied by other
  3260      parts of the code generator framework).
  3261 
  3262   b) Code equations stemming from explicit declarations (e.g. code
  3263      attribute) gain priority over default code equations stemming
  3264      from definition, primrec, fun etc.
  3265 
  3266 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  3267 
  3268 * Unified theorem tables for both code generators.  Thus [code
  3269 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  3270 
  3271 * Command 'find_consts' searches for constants based on type and name
  3272 patterns, e.g.
  3273 
  3274     find_consts "_ => bool"
  3275 
  3276 By default, matching is against subtypes, but it may be restricted to
  3277 the whole type.  Searching by name is possible.  Multiple queries are
  3278 conjunctive and queries may be negated by prefixing them with a
  3279 hyphen:
  3280 
  3281     find_consts strict: "_ => bool" name: "Int" -"int => int"
  3282 
  3283 * New 'find_theorems' criterion "solves" matches theorems that
  3284 directly solve the current goal (modulo higher-order unification).
  3285 
  3286 * Auto solve feature for main theorem statements: whenever a new goal
  3287 is stated, "find_theorems solves" is called; any theorems that could
  3288 solve the lemma directly are listed as part of the goal state.
  3289 Cf. associated options in Proof General Isabelle settings menu,
  3290 enabled by default, with reasonable timeout for pathological cases of
  3291 higher-order unification.
  3292 
  3293 
  3294 *** Document preparation ***
  3295 
  3296 * Antiquotation @{lemma} now imitates a regular terminal proof,
  3297 demanding keyword 'by' and supporting the full method expression
  3298 syntax just like the Isar command 'by'.
  3299 
  3300 
  3301 *** HOL ***
  3302 
  3303 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  3304 points Main and Complex_Main remain as before.
  3305 
  3306 * Logic image HOL-Plain provides a minimal HOL with the most important
  3307 tools available (inductive, datatype, primrec, ...).  This facilitates
  3308 experimentation and tool development.  Note that user applications
  3309 (and library theories) should never refer to anything below theory
  3310 Main, as before.
  3311 
  3312 * Logic image HOL-Main stops at theory Main, and thus facilitates
  3313 experimentation due to shorter build times.
  3314 
  3315 * Logic image HOL-NSA contains theories of nonstandard analysis which
  3316 were previously part of former HOL-Complex.  Entry point Hyperreal
  3317 remains valid, but theories formerly using Complex_Main should now use
  3318 new entry point Hypercomplex.
  3319 
  3320 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  3321 Posix processes.  Avoids potentially expensive forking of the ML
  3322 process.  New thread-based implementation also works on non-Unix
  3323 platforms (Cygwin).  Provers are no longer hardwired, but defined
  3324 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  3325 commands are covered in the isar-ref manual.
  3326 
  3327 * Wrapper scripts for remote SystemOnTPTP service allows to use
  3328 sledgehammer without local ATP installation (Vampire etc.). Other
  3329 provers may be included via suitable ML wrappers, see also
  3330 src/HOL/ATP_Linkup.thy.
  3331 
  3332 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  3333 menu.
  3334 
  3335 * The metis method no longer fails because the theorem is too trivial
  3336 (contains the empty clause).
  3337 
  3338 * The metis method now fails in the usual manner, rather than raising
  3339 an exception, if it determines that it cannot prove the theorem.
  3340 
  3341 * Method "coherent" implements a prover for coherent logic (see also
  3342 src/Tools/coherent.ML).
  3343 
  3344 * Constants "undefined" and "default" replace "arbitrary".  Usually
  3345 "undefined" is the right choice to replace "arbitrary", though
  3346 logically there is no difference.  INCOMPATIBILITY.
  3347 
  3348 * Command "value" now integrates different evaluation mechanisms.  The
  3349 result of the first successful evaluation mechanism is printed.  In
  3350 square brackets a particular named evaluation mechanisms may be
  3351 specified (currently, [SML], [code] or [nbe]).  See further
  3352 src/HOL/ex/Eval_Examples.thy.
  3353 
  3354 * Normalization by evaluation now allows non-leftlinear equations.
  3355 Declare with attribute [code nbe].
  3356 
  3357 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  3358 as the structured Isar versions "cases" and "induct", cf. the
  3359 corresponding "cases" and "induct" attributes.  Mutual induction rules
  3360 are now presented as a list of individual projections
  3361 (e.g. foo_bar.inducts for types foo and bar); the old format with
  3362 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  3363 rare situations a different rule is selected --- notably nested tuple
  3364 elimination instead of former prod.exhaust: use explicit (case_tac t
  3365 rule: prod.exhaust) here.
  3366 
  3367 * Attributes "cases", "induct", "coinduct" support "del" option.
  3368 
  3369 * Removed fact "case_split_thm", which duplicates "case_split".
  3370 
  3371 * The option datatype has been moved to a new theory Option.  Renamed
  3372 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  3373 
  3374 * New predicate "strict_mono" classifies strict functions on partial
  3375 orders.  With strict functions on linear orders, reasoning about
  3376 (in)equalities is facilitated by theorems "strict_mono_eq",
  3377 "strict_mono_less_eq" and "strict_mono_less".
  3378 
  3379 * Some set operations are now proper qualified constants with
  3380 authentic syntax.  INCOMPATIBILITY:
  3381 
  3382     op Int ~>   Set.Int
  3383     op Un ~>    Set.Un
  3384     INTER ~>    Set.INTER
  3385     UNION ~>    Set.UNION
  3386     Inter ~>    Set.Inter
  3387     Union ~>    Set.Union
  3388     {} ~>       Set.empty
  3389     UNIV ~>     Set.UNIV
  3390 
  3391 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  3392 theory Set.
  3393 
  3394 * Auxiliary class "itself" has disappeared -- classes without any
  3395 parameter are treated as expected by the 'class' command.
  3396 
  3397 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  3398 
  3399 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  3400 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  3401 
  3402 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  3403 method "approximation".  It proves formulas on real values by using
  3404 interval arithmetic.  In the formulas are also the transcendental
  3405 functions sin, cos, tan, atan, ln, exp and the constant pi are
  3406 allowed. For examples see
  3407 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  3408 
  3409 * Theory "Reflection" now resides in HOL/Library.
  3410 
  3411 * Entry point to Word library now simply named "Word".
  3412 INCOMPATIBILITY.
  3413 
  3414 * Made source layout more coherent with logical distribution
  3415 structure:
  3416 
  3417     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  3418     src/HOL/Library/Code_Message.thy ~> src/HOL/
  3419     src/HOL/Library/GCD.thy ~> src/HOL/
  3420     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  3421     src/HOL/Library/Parity.thy ~> src/HOL/
  3422     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  3423     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  3424     src/HOL/Real/Lubs.thy ~> src/HOL/
  3425     src/HOL/Real/PReal.thy ~> src/HOL/
  3426     src/HOL/Real/Rational.thy ~> src/HOL/
  3427     src/HOL/Real/RComplete.thy ~> src/HOL/
  3428     src/HOL/Real/RealDef.thy ~> src/HOL/
  3429     src/HOL/Real/RealPow.thy ~> src/HOL/
  3430     src/HOL/Real/Real.thy ~> src/HOL/
  3431     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  3432     src/HOL/Complex/Complex.thy ~> src/HOL/
  3433     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  3434     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  3435     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  3436     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  3437     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  3438     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  3439     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  3440     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  3441     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  3442     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  3443     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  3444     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  3445     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  3446     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  3447     src/HOL/Real/Float ~> src/HOL/Library/
  3448     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  3449     src/HOL/Real/RealVector.thy ~> src/HOL/
  3450 
  3451     src/HOL/arith_data.ML ~> src/HOL/Tools
  3452     src/HOL/hologic.ML ~> src/HOL/Tools
  3453     src/HOL/simpdata.ML ~> src/HOL/Tools
  3454     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3455     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3456     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3457     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3458     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3459     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3460     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3461 
  3462     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3463     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3464     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3465     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3466     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3467     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3468 
  3469 * If methods "eval" and "evaluation" encounter a structured proof
  3470 state with !!/==>, only the conclusion is evaluated to True (if
  3471 possible), avoiding strange error messages.
  3472 
  3473 * Method "sizechange" automates termination proofs using (a
  3474 modification of) the size-change principle.  Requires SAT solver.  See
  3475 src/HOL/ex/Termination.thy for examples.
  3476 
  3477 * Simplifier: simproc for let expressions now unfolds if bound
  3478 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3479 
  3480 * Method "arith": Linear arithmetic now ignores all inequalities when
  3481 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3482 
  3483 * New attribute "arith" for facts that should always be used
  3484 automatically by arithmetic. It is intended to be used locally in
  3485 proofs, e.g.
  3486 
  3487   assumes [arith]: "x > 0"
  3488 
  3489 Global usage is discouraged because of possible performance impact.
  3490 
  3491 * New classes "top" and "bot" with corresponding operations "top" and
  3492 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3493 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3494 
  3495 * Changed definition lemma "less_fun_def" in order to provide an
  3496 instance for preorders on functions; use lemma "less_le" instead.
  3497 INCOMPATIBILITY.
  3498 
  3499 * Theory Orderings: class "wellorder" moved here, with explicit
  3500 induction rule "less_induct" as assumption.  For instantiation of
  3501 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3502 INCOMPATIBILITY.
  3503 
  3504 * Theory Orderings: added class "preorder" as superclass of "order".
  3505 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3506 etc. slightly changed.  Some theorems named order_class.* now named
  3507 preorder_class.*.
  3508 
  3509 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3510 "diag" to "Id_on".
  3511 
  3512 * Theory Finite_Set: added a new fold combinator of type
  3513 
  3514   ('a => 'b => 'b) => 'b => 'a set => 'b
  3515 
  3516 Occasionally this is more convenient than the old fold combinator
  3517 which is now defined in terms of the new one and renamed to
  3518 fold_image.
  3519 
  3520 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3521 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3522 extended with further lemmas!).  At the moment both still exist but
  3523 the former will disappear at some point.
  3524 
  3525 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3526 class recpower.  Type-specific simp rules for various recpower types
  3527 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3528 
  3529 rat_power_0    -> power_0
  3530 rat_power_Suc  -> power_Suc
  3531 realpow_0      -> power_0
  3532 realpow_Suc    -> power_Suc
  3533 complexpow_0   -> power_0
  3534 complexpow_Suc -> power_Suc
  3535 power_poly_0   -> power_0
  3536 power_poly_Suc -> power_Suc
  3537 
  3538 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3539 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3540 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3541 of lemmas from Divides has been generalized from nat to class
  3542 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3543 renames resulting from duplicate elimination:
  3544 
  3545     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3546     zero_dvd_iff ~>         dvd_0_left_iff
  3547     dvd_0 ~>                dvd_0_right
  3548     DIVISION_BY_ZERO_DIV ~> div_by_0
  3549     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3550     mult_div ~>             div_mult_self2_is_id
  3551     mult_mod ~>             mod_mult_self2_is_0
  3552 
  3553 * Theory IntDiv: removed many lemmas that are instances of class-based
  3554 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3555 rename old lemmas as follows:
  3556 
  3557 dvd_diff               -> nat_dvd_diff
  3558 dvd_zminus_iff         -> dvd_minus_iff
  3559 mod_add1_eq            -> mod_add_eq
  3560 mod_mult1_eq           -> mod_mult_right_eq
  3561 mod_mult1_eq'          -> mod_mult_left_eq
  3562 mod_mult_distrib_mod   -> mod_mult_eq
  3563 nat_mod_add_left_eq    -> mod_add_left_eq
  3564 nat_mod_add_right_eq   -> mod_add_right_eq
  3565 nat_mod_div_trivial    -> mod_div_trivial
  3566 nat_mod_mod_trivial    -> mod_mod_trivial
  3567 zdiv_zadd_self1        -> div_add_self1
  3568 zdiv_zadd_self2        -> div_add_self2
  3569 zdiv_zmult_self1       -> div_mult_self2_is_id
  3570 zdiv_zmult_self2       -> div_mult_self1_is_id
  3571 zdvd_triv_left         -> dvd_triv_left
  3572 zdvd_triv_right        -> dvd_triv_right
  3573 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3574 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3575 zmod_zadd_left_eq      -> mod_add_left_eq
  3576 zmod_zadd_right_eq     -> mod_add_right_eq
  3577 zmod_zadd_self1        -> mod_add_self1
  3578 zmod_zadd_self2        -> mod_add_self2
  3579 zmod_zadd1_eq          -> mod_add_eq
  3580 zmod_zdiff1_eq         -> mod_diff_eq
  3581 zmod_zdvd_zmod         -> mod_mod_cancel
  3582 zmod_zmod_cancel       -> mod_mod_cancel
  3583 zmod_zmult_self1       -> mod_mult_self2_is_0
  3584 zmod_zmult_self2       -> mod_mult_self1_is_0
  3585 zmod_1                 -> mod_by_1
  3586 zdiv_1                 -> div_by_1
  3587 zdvd_abs1              -> abs_dvd_iff
  3588 zdvd_abs2              -> dvd_abs_iff
  3589 zdvd_refl              -> dvd_refl
  3590 zdvd_trans             -> dvd_trans
  3591 zdvd_zadd              -> dvd_add
  3592 zdvd_zdiff             -> dvd_diff
  3593 zdvd_zminus_iff        -> dvd_minus_iff
  3594 zdvd_zminus2_iff       -> minus_dvd_iff
  3595 zdvd_zmultD            -> dvd_mult_right
  3596 zdvd_zmultD2           -> dvd_mult_left
  3597 zdvd_zmult_mono        -> mult_dvd_mono
  3598 zdvd_0_right           -> dvd_0_right
  3599 zdvd_0_left            -> dvd_0_left_iff
  3600 zdvd_1_left            -> one_dvd
  3601 zminus_dvd_iff         -> minus_dvd_iff
  3602 
  3603 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3604 
  3605 * The real numbers offer decimal input syntax: 12.34 is translated
  3606 into 1234/10^2. This translation is not reversed upon output.
  3607 
  3608 * Theory Library/Polynomial defines an abstract type 'a poly of
  3609 univariate polynomials with coefficients of type 'a.  In addition to
  3610 the standard ring operations, it also supports div and mod.  Code
  3611 generation is also supported, using list-style constructors.
  3612 
  3613 * Theory Library/Inner_Product defines a class of real_inner for real
  3614 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3615 => real.  Class real_inner is a subclass of real_normed_vector from
  3616 theory RealVector.
  3617 
  3618 * Theory Library/Product_Vector provides instances for the product
  3619 type 'a * 'b of several classes from RealVector and Inner_Product.
  3620 Definitions of addition, subtraction, scalar multiplication, norms,
  3621 and inner products are included.
  3622 
  3623 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3624 addition to the field operations, numerals and case syntax are also
  3625 supported.
  3626 
  3627 * Theory Library/Diagonalize provides constructive version of Cantor's
  3628 first diagonalization argument.
  3629 
  3630 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3631 zlcm (for int); carried together from various gcd/lcm developements in
  3632 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3633 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3634 may recover tupled syntax as follows:
  3635 
  3636     hide (open) const gcd
  3637     abbreviation gcd where
  3638       "gcd == (%(a, b). GCD.gcd a b)"
  3639     notation (output)
  3640       GCD.gcd ("gcd '(_, _')")
  3641 
  3642 The same works for lcm, zgcd, zlcm.
  3643 
  3644 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3645 instantiations for algebraic structures.  Removed some duplicate
  3646 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3647 
  3648 * ML antiquotation @{code} takes a constant as argument and generates
  3649 corresponding code in background and inserts name of the corresponding
  3650 resulting ML value/function/datatype constructor binding in place.
  3651 All occurrences of @{code} with a single ML block are generated
  3652 simultaneously.  Provides a generic and safe interface for
  3653 instrumentalizing code generation.  See
  3654 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3655 In future you ought to refrain from ad-hoc compiling generated SML
  3656 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3657 cannot refer to constants for which user-defined serializations are
  3658 set.  Refer to the corresponding ML counterpart directly in that
  3659 cases.
  3660 
  3661 * Command 'rep_datatype': instead of theorem names the command now
  3662 takes a list of terms denoting the constructors of the type to be
  3663 represented as datatype.  The characteristic theorems have to be
  3664 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3665 have disappeared in favour of existing ones:
  3666 
  3667     unit_induct                 ~> unit.induct
  3668     prod_induct                 ~> prod.induct
  3669     sum_induct                  ~> sum.induct
  3670     Suc_Suc_eq                  ~> nat.inject
  3671     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3672 
  3673 
  3674 *** HOL-Algebra ***
  3675 
  3676 * New locales for orders and lattices where the equivalence relation
  3677 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3678 locales use a record structure with field eq for the equivalence.
  3679 
  3680 * New theory of factorial domains.
  3681 
  3682 * Units_l_inv and Units_r_inv are now simp rules by default.
  3683 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3684 and/or r_inv will now also require deletion of these lemmas.
  3685 
  3686 * Renamed the following theorems, INCOMPATIBILITY:
  3687 
  3688 UpperD ~> Upper_memD
  3689 LowerD ~> Lower_memD
  3690 least_carrier ~> least_closed
  3691 greatest_carrier ~> greatest_closed
  3692 greatest_Lower_above ~> greatest_Lower_below
  3693 one_zero ~> carrier_one_zero
  3694 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3695 
  3696 
  3697 *** HOL-Nominal ***
  3698 
  3699 * Nominal datatypes can now contain type-variables.
  3700 
  3701 * Commands 'nominal_inductive' and 'equivariance' work with local
  3702 theory targets.
  3703 
  3704 * Nominal primrec can now works with local theory targets and its
  3705 specification syntax now conforms to the general format as seen in
  3706 'inductive' etc.
  3707 
  3708 * Method "perm_simp" honours the standard simplifier attributes
  3709 (no_asm), (no_asm_use) etc.
  3710 
  3711 * The new predicate #* is defined like freshness, except that on the
  3712 left hand side can be a set or list of atoms.
  3713 
  3714 * Experimental command 'nominal_inductive2' derives strong induction
  3715 principles for inductive definitions.  In contrast to
  3716 'nominal_inductive', which can only deal with a fixed number of
  3717 binders, it can deal with arbitrary expressions standing for sets of
  3718 atoms to be avoided.  The only inductive definition we have at the
  3719 moment that needs this generalisation is the typing rule for Lets in
  3720 the algorithm W:
  3721 
  3722  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3723  -----------------------------------------------------------------
  3724          Gamma |- Let x be t1 in t2 : T2
  3725 
  3726 In this rule one wants to avoid all the binders that are introduced by
  3727 "close Gamma T1".  We are looking for other examples where this
  3728 feature might be useful.  Please let us know.
  3729 
  3730 
  3731 *** HOLCF ***
  3732 
  3733 * Reimplemented the simplification procedure for proving continuity
  3734 subgoals.  The new simproc is extensible; users can declare additional
  3735 continuity introduction rules with the attribute [cont2cont].
  3736 
  3737 * The continuity simproc now uses a different introduction rule for
  3738 solving continuity subgoals on terms with lambda abstractions.  In
  3739 some rare cases the new simproc may fail to solve subgoals that the
  3740 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3741 Potential INCOMPATIBILITY.
  3742 
  3743 * Command 'fixrec': specification syntax now conforms to the general
  3744 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3745 examples.  INCOMPATIBILITY.
  3746 
  3747 
  3748 *** ZF ***
  3749 
  3750 * Proof of Zorn's Lemma for partial orders.
  3751 
  3752 
  3753 *** ML ***
  3754 
  3755 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3756 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3757 depends on multithreading, so timouts will not work before Poly/ML
  3758 5.2.1!
  3759 
  3760 * High-level support for concurrent ML programming, see
  3761 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3762 particularly convenient to organize independent functional
  3763 computations.  The concept of "synchronized variables" provides a
  3764 higher-order interface for components with shared state, avoiding the
  3765 delicate details of mutexes and condition variables.  (Requires
  3766 Poly/ML 5.2.1 or later.)
  3767 
  3768 * ML bindings produced via Isar commands are stored within the Isar
  3769 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3770 become thread-safe and work with undo as expected (concerning
  3771 top-level bindings, not side-effects on global references).
  3772 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3773 compiler at runtime; really global bindings need to be given outside a
  3774 theory.  (Requires Poly/ML 5.2 or later.)
  3775 
  3776 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3777 context.  Top-level ML bindings are stored within the proof context in
  3778 a purely sequential fashion, disregarding the nested proof structure.
  3779 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3780 proof.  (Requires Poly/ML 5.2 or later.)
  3781 
  3782 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3783 and Method.setup, as well as Isar commands 'attribute_setup' and
  3784 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3785 existing code accordingly, or use plain 'setup' together with old
  3786 Method.add_method.
  3787 
  3788 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3789 to 'a -> thm, while results are always tagged with an authentic oracle
  3790 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3791 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3792 accordingly.  Note that extra performance may be gained by producing
  3793 the cterm carefully, avoiding slow Thm.cterm_of.
  3794 
  3795 * Simplified interface for defining document antiquotations via
  3796 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3797 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3798 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3799 examples.
  3800 
  3801 * More systematic treatment of long names, abstract name bindings, and
  3802 name space operations.  Basic operations on qualified names have been
  3803 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3804 Long_Name.append.  Old type bstring has been mostly replaced by
  3805 abstract type binding (see structure Binding), which supports precise
  3806 qualification by packages and local theory targets, as well as proper
  3807 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3808 bstring values into Binding.name, or better pass through abstract
  3809 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3810 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3811 
  3812 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3813 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3814 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3815 
  3816 * Disposed old type and term read functions (Sign.read_def_typ,
  3817 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3818 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3819 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3820 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3821 resort for legacy applications.
  3822 
  3823 * Disposed old declarations, tactics, tactic combinators that refer to
  3824 the simpset or claset of an implicit theory (such as Addsimps,
  3825 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3826 embedded ML text, or local_simpset_of with a proper context passed as
  3827 explicit runtime argument.
  3828 
  3829 * Rules and tactics that read instantiations (read_instantiate,
  3830 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3831 context, which is required for parsing and type-checking.  Moreover,
  3832 the variables are specified as plain indexnames, not string encodings
  3833 thereof.  INCOMPATIBILITY.
  3834 
  3835 * Generic Toplevel.add_hook interface allows to analyze the result of
  3836 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3837 for theorem dependency output of transactions resulting in a new
  3838 theory state.
  3839 
  3840 * ML antiquotations: block-structured compilation context indicated by
  3841 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3842 
  3843   @{binding name}                         - basic name binding
  3844   @{let ?pat = term}                      - term abbreviation (HO matching)
  3845   @{note name = fact}                     - fact abbreviation
  3846   @{thm fact}                             - singleton fact (with attributes)
  3847   @{thms fact}                            - general fact (with attributes)
  3848   @{lemma prop by method}                 - singleton goal
  3849   @{lemma prop by meth1 meth2}            - singleton goal
  3850   @{lemma prop1 ... propN by method}      - general goal
  3851   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3852   @{lemma (open) ...}                     - open derivation
  3853 
  3854 
  3855 *** System ***
  3856 
  3857 * The Isabelle "emacs" tool provides a specific interface to invoke
  3858 Proof General / Emacs, with more explicit failure if that is not
  3859 installed (the old isabelle-interface script silently falls back on
  3860 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3861 installation location of the Proof General distribution.
  3862 
  3863 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3864 the Isabelle process into a JVM/Scala application.  See
  3865 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3866 process wrapper has been discontinued.)
  3867 
  3868 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3869 
  3870 * Various status messages (with exact source position information) are
  3871 emitted, if proper markup print mode is enabled.  This allows
  3872 user-interface components to provide detailed feedback on internal
  3873 prover operations.
  3874 
  3875 
  3876 
  3877 New in Isabelle2008 (June 2008)
  3878 -------------------------------
  3879 
  3880 *** General ***
  3881 
  3882 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3883 and updated, with formally checked references as hyperlinks.
  3884 
  3885 * Theory loader: use_thy (and similar operations) no longer set the
  3886 implicit ML context, which was occasionally hard to predict and in
  3887 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3888 provides a proper context already.
  3889 
  3890 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3891 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3892 'use' within a theory file will do the job.
  3893 
  3894 * Name space merge now observes canonical order, i.e. the second space
  3895 is inserted into the first one, while existing entries in the first
  3896 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3897 swap theory imports.
  3898 
  3899 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3900 INCOMPATIBILITY in identifier syntax etc.
  3901 
  3902 * Outer syntax: string tokens no longer admit escaped white space,
  3903 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3904 white space without escapes.
  3905 
  3906 * Outer syntax: string tokens may contain arbitrary character codes
  3907 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3908 "foo_bar".
  3909 
  3910 
  3911 *** Pure ***
  3912 
  3913 * Context-dependent token translations.  Default setup reverts locally
  3914 fixed variables, and adds hilite markup for undeclared frees.
  3915 
  3916 * Unused theorems can be found using the new command 'unused_thms'.
  3917 There are three ways of invoking it:
  3918 
  3919 (1) unused_thms
  3920      Only finds unused theorems in the current theory.
  3921 
  3922 (2) unused_thms thy_1 ... thy_n -
  3923      Finds unused theorems in the current theory and all of its ancestors,
  3924      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3925 
  3926 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3927      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3928      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3929      their ancestors.
  3930 
  3931 In order to increase the readability of the list produced by
  3932 unused_thms, theorems that have been created by a particular instance
  3933 of a theory command such as 'inductive' or 'function' are considered
  3934 to belong to the same "group", meaning that if at least one theorem in
  3935 this group is used, the other theorems in the same group are no longer
  3936 reported as unused.  Moreover, if all theorems in the group are
  3937 unused, only one theorem in the group is displayed.
  3938 
  3939 Note that proof objects have to be switched on in order for
  3940 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3941 usually the case when using Proof General with the default settings).
  3942 
  3943 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3944 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3945 duplicate fact bindings, or even accidental fact duplications.  Note
  3946 that tools may maintain dynamically scoped facts systematically, using
  3947 PureThy.add_thms_dynamic.
  3948 
  3949 * Command 'hide' now allows to hide from "fact" name space as well.
  3950 
  3951 * Eliminated destructive theorem database, simpset, claset, and
  3952 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3953 update of theories within ML code.
  3954 
  3955 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3956 INCOMPATIBILITY, object-logics depending on former Pure require
  3957 additional setup PureThy.old_appl_syntax_setup; object-logics
  3958 depending on former CPure need to refer to Pure.
  3959 
  3960 * Commands 'use' and 'ML' are now purely functional, operating on
  3961 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3962 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3963 INCOMPATIBILITY.
  3964 
  3965 * Command 'setup': discontinued implicit version with ML reference.
  3966 
  3967 * Instantiation target allows for simultaneous specification of class
  3968 instance operations together with an instantiation proof.
  3969 Type-checking phase allows to refer to class operations uniformly.
  3970 See src/HOL/Complex/Complex.thy for an Isar example and
  3971 src/HOL/Library/Eval.thy for an ML example.
  3972 
  3973 * Indexing of literal facts: be more serious about including only
  3974 facts from the visible specification/proof context, but not the
  3975 background context (locale etc.).  Affects `prop` notation and method
  3976 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3977 situations.
  3978 
  3979 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3980 "(open)" option, which used to expose internal bound variables to the
  3981 proof text.
  3982 
  3983 * Isar statements: removed obsolete case "rule_context".
  3984 INCOMPATIBILITY, better use explicit fixes/assumes.
  3985 
  3986 * Locale proofs: default proof step now includes 'unfold_locales';
  3987 hence 'proof' without argument may be used to unfold locale
  3988 predicates.
  3989 
  3990 
  3991 *** Document preparation ***
  3992 
  3993 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3994 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3995 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3996 spot); renamed link color from "darkblue" to "linkcolor" (default
  3997 value unchanged, can be redefined via \definecolor); no longer sets
  3998 "a4paper" option (unnecessary or even intrusive).
  3999 
  4000 * Antiquotation @{lemma A method} proves proposition A by the given
  4001 method (either a method name or a method name plus (optional) method
  4002 arguments in parentheses) and prints A just like @{prop A}.
  4003 
  4004 
  4005 *** HOL ***
  4006 
  4007 * New primrec package.  Specification syntax conforms in style to
  4008 definition/function/....  No separate induction rule is provided.  The
  4009 "primrec" command distinguishes old-style and new-style specifications
  4010 by syntax.  The former primrec package is now named OldPrimrecPackage.
  4011 When adjusting theories, beware: constants stemming from new-style
  4012 primrec specifications have authentic syntax.
  4013 
  4014 * Metis prover is now an order of magnitude faster, and also works
  4015 with multithreading.
  4016 
  4017 * Metis: the maximum number of clauses that can be produced from a
  4018 theorem is now given by the attribute max_clauses.  Theorems that
  4019 exceed this number are ignored, with a warning printed.
  4020 
  4021 * Sledgehammer no longer produces structured proofs by default. To
  4022 enable, declare [[sledgehammer_full = true]].  Attributes
  4023 reconstruction_modulus, reconstruction_sorts renamed
  4024 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  4025 
  4026 * Method "induct_scheme" derives user-specified induction rules
  4027 from well-founded induction and completeness of patterns. This factors
  4028 out some operations that are done internally by the function package
  4029 and makes them available separately.  See
  4030 src/HOL/ex/Induction_Scheme.thy for examples.
  4031 
  4032 * More flexible generation of measure functions for termination
  4033 proofs: Measure functions can be declared by proving a rule of the
  4034 form "is_measure f" and giving it the [measure_function] attribute.
  4035 The "is_measure" predicate is logically meaningless (always true), and
  4036 just guides the heuristic.  To find suitable measure functions, the
  4037 termination prover sets up the goal "is_measure ?f" of the appropriate
  4038 type and generates all solutions by prolog-style backwards proof using
  4039 the declared rules.
  4040 
  4041 This setup also deals with rules like 
  4042 
  4043   "is_measure f ==> is_measure (list_size f)"
  4044 
  4045 which accommodates nested datatypes that recurse through lists.
  4046 Similar rules are predeclared for products and option types.
  4047 
  4048 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  4049 
  4050   INCOMPATIBILITIES:
  4051 
  4052   - Definitions of overloaded constants on sets have to be replaced by
  4053     definitions on => and bool.
  4054 
  4055   - Some definitions of overloaded operators on sets can now be proved
  4056     using the definitions of the operators on => and bool.  Therefore,
  4057     the following theorems have been renamed:
  4058 
  4059       subset_def   -> subset_eq
  4060       psubset_def  -> psubset_eq
  4061       set_diff_def -> set_diff_eq
  4062       Compl_def    -> Compl_eq
  4063       Sup_set_def  -> Sup_set_eq
  4064       Inf_set_def  -> Inf_set_eq
  4065       sup_set_def  -> sup_set_eq
  4066       inf_set_def  -> inf_set_eq
  4067 
  4068   - Due to the incompleteness of the HO unification algorithm, some
  4069     rules such as subst may require manual instantiation, if some of
  4070     the unknowns in the rule is a set.
  4071 
  4072   - Higher order unification and forward proofs:
  4073     The proof pattern
  4074 
  4075       have "P (S::'a set)" <...>
  4076       then have "EX S. P S" ..
  4077 
  4078     no longer works (due to the incompleteness of the HO unification
  4079     algorithm) and must be replaced by the pattern
  4080 
  4081       have "EX S. P S"
  4082       proof
  4083         show "P S" <...>
  4084       qed
  4085 
  4086   - Calculational reasoning with subst (or similar rules):
  4087     The proof pattern
  4088 
  4089       have "P (S::'a set)" <...>
  4090       also have "S = T" <...>
  4091       finally have "P T" .
  4092 
  4093     no longer works (for similar reasons as the previous example) and
  4094     must be replaced by something like
  4095 
  4096       have "P (S::'a set)" <...>
  4097       moreover have "S = T" <...>
  4098       ultimately have "P T" by simp
  4099 
  4100   - Tactics or packages written in ML code:
  4101     Code performing pattern matching on types via
  4102 
  4103       Type ("set", [T]) => ...
  4104 
  4105     must be rewritten. Moreover, functions like strip_type or
  4106     binder_types no longer return the right value when applied to a
  4107     type of the form
  4108 
  4109       T1 => ... => Tn => U => bool
  4110 
  4111     rather than
  4112 
  4113       T1 => ... => Tn => U set
  4114 
  4115 * Merged theories Wellfounded_Recursion, Accessible_Part and
  4116 Wellfounded_Relations to theory Wellfounded.
  4117 
  4118 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  4119 
  4120 * Class finite no longer treats UNIV as class parameter.  Use class
  4121 enum from theory Library/Enum instead to achieve a similar effect.
  4122 INCOMPATIBILITY.
  4123 
  4124 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  4125 and "Cons".  INCOMPATIBILITY.
  4126 
  4127 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  4128 Potential INCOMPATIBILITY.
  4129 
  4130 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  4131 injective_fst_snd removed, use split_eta and prod_eqI instead.
  4132 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  4133 
  4134 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  4135 the same name in theory Orderings:
  4136 
  4137   less_trans
  4138   less_linear
  4139   le_imp_less_or_eq
  4140   le_less_trans
  4141   less_le_trans
  4142   less_not_sym
  4143   less_asym
  4144 
  4145 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  4146 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  4147 and different variable names.
  4148 
  4149 * Library/Option_ord.thy: Canonical order on option type.
  4150 
  4151 * Library/RBT.thy: Red-black trees, an efficient implementation of
  4152 finite maps.
  4153 
  4154 * Library/Countable.thy: Type class for countable types.
  4155 
  4156 * Theory Int: The representation of numerals has changed.  The infix
  4157 operator BIT and the bit datatype with constructors B0 and B1 have
  4158 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  4159 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  4160 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  4161 accordingly.
  4162 
  4163 * Theory Nat: definition of <= and < on natural numbers no longer
  4164 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  4165 le_def and less_def have disappeared.  Consider lemmas not_less
  4166 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  4167 
  4168 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  4169 (whose purpose mainly is for various fold_set functionals) have been
  4170 abandoned in favor of the existing algebraic classes
  4171 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  4172 lower_semilattice (resp. upper_semilattice) and linorder.
  4173 INCOMPATIBILITY.
  4174 
  4175 * Theory Transitive_Closure: induct and cases rules now declare proper
  4176 case_names ("base" and "step").  INCOMPATIBILITY.
  4177 
  4178 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  4179 lattices.  The form set-specific version is available as
  4180 Inductive.lfp_ordinal_induct_set.
  4181 
  4182 * Renamed theorems "power.simps" to "power_int.simps".
  4183 INCOMPATIBILITY.
  4184 
  4185 * Class semiring_div provides basic abstract properties of semirings
  4186 with division and modulo operations.  Subsumes former class dvd_mod.
  4187 
  4188 * Merged theories IntDef, Numeral and IntArith into unified theory
  4189 Int.  INCOMPATIBILITY.
  4190 
  4191 * Theory Library/Code_Index: type "index" now represents natural
  4192 numbers rather than integers.  INCOMPATIBILITY.
  4193 
  4194 * New class "uminus" with operation "uminus" (split of from class
  4195 "minus" which now only has operation "minus", binary).
  4196 INCOMPATIBILITY.
  4197 
  4198 * Constants "card", "internal_split", "option_map" now with authentic
  4199 syntax.  INCOMPATIBILITY.
  4200 
  4201 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  4202 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  4203 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  4204 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  4205 Sup_set_def, le_def, less_def, option_map_def now with object
  4206 equality.  INCOMPATIBILITY.
  4207 
  4208 * Records. Removed K_record, and replaced it by pure lambda term
  4209 %x. c. The simplifier setup is now more robust against eta expansion.
  4210 INCOMPATIBILITY: in cases explicitly referring to K_record.
  4211 
  4212 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  4213 
  4214 * Library/ListVector: new theory of arithmetic vector operations.
  4215 
  4216 * Library/Order_Relation: new theory of various orderings as sets of
  4217 pairs.  Defines preorders, partial orders, linear orders and
  4218 well-orders on sets and on types.
  4219 
  4220 
  4221 *** ZF ***
  4222 
  4223 * Renamed some theories to allow to loading both ZF and HOL in the
  4224 same session:
  4225 
  4226   Datatype  -> Datatype_ZF
  4227   Inductive -> Inductive_ZF
  4228   Int       -> Int_ZF
  4229   IntDiv    -> IntDiv_ZF
  4230   Nat       -> Nat_ZF
  4231   List      -> List_ZF
  4232   Main      -> Main_ZF
  4233 
  4234 INCOMPATIBILITY: ZF theories that import individual theories below
  4235 Main might need to be adapted.  Regular theory Main is still
  4236 available, as trivial extension of Main_ZF.
  4237 
  4238 
  4239 *** ML ***
  4240 
  4241 * ML within Isar: antiquotation @{const name} or @{const
  4242 name(typargs)} produces statically-checked Const term.
  4243 
  4244 * Functor NamedThmsFun: data is available to the user as dynamic fact
  4245 (of the same name).  Removed obsolete print command.
  4246 
  4247 * Removed obsolete "use_legacy_bindings" function.
  4248 
  4249 * The ``print mode'' is now a thread-local value derived from a global
  4250 template (the former print_mode reference), thus access becomes
  4251 non-critical.  The global print_mode reference is for session
  4252 management only; user-code should use print_mode_value,
  4253 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  4254 
  4255 * Functions system/system_out provide a robust way to invoke external
  4256 shell commands, with propagation of interrupts (requires Poly/ML
  4257 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  4258 
  4259 
  4260 *** System ***
  4261 
  4262 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  4263 in accordance with Proof General 3.7, which prefers GNU emacs.
  4264 
  4265 * isatool tty runs Isabelle process with plain tty interaction;
  4266 optional line editor may be specified via ISABELLE_LINE_EDITOR
  4267 setting, the default settings attempt to locate "ledit" and "rlwrap".
  4268 
  4269 * isatool browser now works with Cygwin as well, using general
  4270 "javapath" function defined in Isabelle process environment.
  4271 
  4272 * YXML notation provides a simple and efficient alternative to
  4273 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  4274 isatool yxml as described in the Isabelle system manual.
  4275 
  4276 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  4277 provides general wrapper for managing an Isabelle process in a robust
  4278 fashion, with ``cooked'' output from stdin/stderr.
  4279 
  4280 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  4281 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  4282 
  4283 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  4284 way of changing the user's settings is via
  4285 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  4286 script.
  4287 
  4288 * Multithreading.max_threads := 0 refers to the number of actual CPU
  4289 cores of the underlying machine, which is a good starting point for
  4290 optimal performance tuning.  The corresponding usedir option -M allows
  4291 "max" as an alias for "0".  WARNING: does not work on certain versions
  4292 of Mac OS (with Poly/ML 5.1).
  4293 
  4294 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  4295 adverse effect of Isabelle flooding interactive front-ends (notably
  4296 ProofGeneral / XEmacs).
  4297 
  4298 
  4299 
  4300 New in Isabelle2007 (November 2007)
  4301 -----------------------------------
  4302 
  4303 *** General ***
  4304 
  4305 * More uniform information about legacy features, notably a
  4306 warning/error of "Legacy feature: ...", depending on the state of the
  4307 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  4308 legacy features will disappear eventually.
  4309 
  4310 * Theory syntax: the header format ``theory A = B + C:'' has been
  4311 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  4312 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  4313 
  4314 * Theory syntax: the old non-Isar theory file format has been
  4315 discontinued altogether.  Note that ML proof scripts may still be used
  4316 with Isar theories; migration is usually quite simple with the ML
  4317 function use_legacy_bindings.  INCOMPATIBILITY.
  4318 
  4319 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  4320 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  4321 quotes.
  4322 
  4323 * Theory loader: be more serious about observing the static theory
  4324 header specifications (including optional directories), but not the
  4325 accidental file locations of previously successful loads.  The strict
  4326 update policy of former update_thy is now already performed by
  4327 use_thy, so the former has been removed; use_thys updates several
  4328 theories simultaneously, just as 'imports' within a theory header
  4329 specification, but without merging the results.  Potential
  4330 INCOMPATIBILITY: may need to refine theory headers and commands
  4331 ROOT.ML which depend on load order.
  4332 
  4333 * Theory loader: optional support for content-based file
  4334 identification, instead of the traditional scheme of full physical
  4335 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  4336 (cf. the system manual).  The new scheme allows to work with
  4337 non-finished theories in persistent session images, such that source
  4338 files may be moved later on without requiring reloads.
  4339 
  4340 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4341 file (with the same base name as the theory) are considered a legacy
  4342 feature, which will disappear eventually. Even now, the theory loader
  4343 no longer maintains dependencies on such files.
  4344 
  4345 * Syntax: the scope for resolving ambiguities via type-inference is
  4346 now limited to individual terms, instead of whole simultaneous
  4347 specifications as before. This greatly reduces the complexity of the
  4348 syntax module and improves flexibility by separating parsing and
  4349 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  4350 'fixes' etc.) are required in rare situations.
  4351 
  4352 * Syntax: constants introduced by new-style packages ('definition',
  4353 'abbreviation' etc.) are passed through the syntax module in
  4354 ``authentic mode''. This means that associated mixfix annotations
  4355 really stick to such constants, independently of potential name space
  4356 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  4357 trees are represented slightly differently, may need to adapt syntax
  4358 translations accordingly. Use CONST marker in 'translations' and
  4359 @{const_syntax} antiquotation in 'parse_translation' etc.
  4360 
  4361 * Legacy goal package: reduced interface to the bare minimum required
  4362 to keep existing proof scripts running.  Most other user-level
  4363 functions are now part of the OldGoals structure, which is *not* open
  4364 by default (consider isatool expandshort before open OldGoals).
  4365 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  4366 these tend to cause confusion about the actual goal (!) context being
  4367 used here, which is not necessarily the same as the_context().
  4368 
  4369 * Command 'find_theorems': supports "*" wild-card in "name:"
  4370 criterion; "with_dups" option.  Certain ProofGeneral versions might
  4371 support a specific search form (see ProofGeneral/CHANGES).
  4372 
  4373 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  4374 by default, which means that "prems" (and also "fixed variables") are
  4375 suppressed from proof state output.  Note that the ProofGeneral
  4376 settings mechanism allows to change and save options persistently, but
  4377 older versions of Isabelle will fail to start up if a negative prems
  4378 limit is imposed.
  4379 
  4380 * Local theory targets may be specified by non-nested blocks of
  4381 ``context/locale/class ... begin'' followed by ``end''.  The body may
  4382 contain definitions, theorems etc., including any derived mechanism
  4383 that has been implemented on top of these primitives.  This concept
  4384 generalizes the existing ``theorem (in ...)'' towards more versatility
  4385 and scalability.
  4386 
  4387 * Proof General interface: proper undo of final 'end' command;
  4388 discontinued Isabelle/classic mode (ML proof scripts).
  4389 
  4390 
  4391 *** Document preparation ***
  4392 
  4393 * Added antiquotation @{theory name} which prints the given name,
  4394 after checking that it refers to a valid ancestor theory in the
  4395 current context.
  4396 
  4397 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  4398 check the given source text as ML type/structure, printing verbatim.
  4399 
  4400 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  4401 "c args == rhs" given in the current context.  (Any number of
  4402 arguments may be given on the LHS.)
  4403 
  4404 
  4405 *** Pure ***
  4406 
  4407 * The 'class' package offers a combination of axclass and locale to
  4408 achieve Haskell-like type classes in Isabelle.  Definitions and
  4409 theorems within a class context produce both relative results (with
  4410 implicit parameters according to the locale context), and polymorphic
  4411 constants with qualified polymorphism (according to the class
  4412 context).  Within the body context of a 'class' target, a separate
  4413 syntax layer ("user space type system") takes care of converting
  4414 between global polymorphic consts and internal locale representation.
  4415 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  4416 "isatool doc classes" provides a tutorial.
  4417 
  4418 * Generic code generator framework allows to generate executable
  4419 code for ML and Haskell (including Isabelle classes).  A short usage
  4420 sketch:
  4421 
  4422     internal compilation:
  4423         export_code <list of constants (term syntax)> in SML
  4424     writing SML code to a file:
  4425         export_code <list of constants (term syntax)> in SML <filename>
  4426     writing OCaml code to a file:
  4427         export_code <list of constants (term syntax)> in OCaml <filename>
  4428     writing Haskell code to a bunch of files:
  4429         export_code <list of constants (term syntax)> in Haskell <filename>
  4430 
  4431     evaluating closed propositions to True/False using code generation:
  4432         method ``eval''
  4433 
  4434 Reasonable default setup of framework in HOL.
  4435 
  4436 Theorem attributs for selecting and transforming function equations theorems:
  4437 
  4438     [code fun]:        select a theorem as function equation for a specific constant
  4439     [code fun del]:    deselect a theorem as function equation for a specific constant
  4440     [code inline]:     select an equation theorem for unfolding (inlining) in place
  4441     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  4442 
  4443 User-defined serializations (target in {SML, OCaml, Haskell}):
  4444 
  4445     code_const <and-list of constants (term syntax)>
  4446       {(target) <and-list of const target syntax>}+
  4447 
  4448     code_type <and-list of type constructors>
  4449       {(target) <and-list of type target syntax>}+
  4450 
  4451     code_instance <and-list of instances>
  4452       {(target)}+
  4453         where instance ::= <type constructor> :: <class>
  4454 
  4455     code_class <and_list of classes>
  4456       {(target) <and-list of class target syntax>}+
  4457         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4458 
  4459 code_instance and code_class only are effective to target Haskell.
  4460 
  4461 For example usage see src/HOL/ex/Codegenerator.thy and
  4462 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4463 generation from Isabelle/HOL theories is available via "isatool doc
  4464 codegen".
  4465 
  4466 * Code generator: consts in 'consts_code' Isar commands are now
  4467 referred to by usual term syntax (including optional type
  4468 annotations).
  4469 
  4470 * Command 'no_translations' removes translation rules from theory
  4471 syntax.
  4472 
  4473 * Overloaded definitions are now actually checked for acyclic
  4474 dependencies.  The overloading scheme is slightly more general than
  4475 that of Haskell98, although Isabelle does not demand an exact
  4476 correspondence to type class and instance declarations.
  4477 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4478 exotic versions of overloading -- at the discretion of the user!
  4479 
  4480 Polymorphic constants are represented via type arguments, i.e. the
  4481 instantiation that matches an instance against the most general
  4482 declaration given in the signature.  For example, with the declaration
  4483 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4484 as c(nat).  Overloading is essentially simultaneous structural
  4485 recursion over such type arguments.  Incomplete specification patterns
  4486 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4487 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4488 Command 'print_theory' outputs the normalized system of recursive
  4489 equations, see section "definitions".
  4490 
  4491 * Configuration options are maintained within the theory or proof
  4492 context (with name and type bool/int/string), providing a very simple
  4493 interface to a poor-man's version of general context data.  Tools may
  4494 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4495 these values using Config.get etc.  Users may change options via an
  4496 associated attribute of the same name.  This form of context
  4497 declaration works particularly well with commands 'declare' or
  4498 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4499 very easy to avoid global references, which would not observe Isar
  4500 toplevel undo/redo and fail to work with multithreading.
  4501 
  4502 Various global ML references of Pure and HOL have been turned into
  4503 configuration options:
  4504 
  4505   Unify.search_bound		unify_search_bound
  4506   Unify.trace_bound		unify_trace_bound
  4507   Unify.trace_simp		unify_trace_simp
  4508   Unify.trace_types		unify_trace_types
  4509   Simplifier.simp_depth_limit	simp_depth_limit
  4510   Blast.depth_limit		blast_depth_limit
  4511   DatatypeProp.dtK		datatype_distinctness_limit
  4512   fast_arith_neq_limit  	fast_arith_neq_limit
  4513   fast_arith_split_limit	fast_arith_split_limit
  4514 
  4515 * Named collections of theorems may be easily installed as context
  4516 data using the functor NamedThmsFun (see also
  4517 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4518 attributes; there is also a toplevel print command.  This facility is
  4519 just a common case of general context data, which is the preferred way
  4520 for anything more complex than just a list of facts in canonical
  4521 order.
  4522 
  4523 * Isar: command 'declaration' augments a local theory by generic
  4524 declaration functions written in ML.  This enables arbitrary content
  4525 being added to the context, depending on a morphism that tells the
  4526 difference of the original declaration context wrt. the application
  4527 context encountered later on.
  4528 
  4529 * Isar: proper interfaces for simplification procedures.  Command
  4530 'simproc_setup' declares named simprocs (with match patterns, and body
  4531 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4532 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4533 
  4534 * Isar: an extra pair of brackets around attribute declarations
  4535 abbreviates a theorem reference involving an internal dummy fact,
  4536 which will be ignored later --- only the effect of the attribute on
  4537 the background context will persist.  This form of in-place
  4538 declarations is particularly useful with commands like 'declare' and
  4539 'using', for example ``have A using [[simproc a]] by simp''.
  4540 
  4541 * Isar: method "assumption" (and implicit closing of subproofs) now
  4542 takes simple non-atomic goal assumptions into account: after applying
  4543 an assumption as a rule the resulting subgoals are solved by atomic
  4544 assumption steps.  This is particularly useful to finish 'obtain'
  4545 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4546 without referring to the original premise "!!x. P x ==> thesis" in the
  4547 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4548 more permissive.
  4549 
  4550 * Isar: implicit use of prems from the Isar proof context is
  4551 considered a legacy feature.  Common applications like ``have A .''
  4552 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4553 referencing facts explicitly here improves readability and
  4554 maintainability of proof texts.
  4555 
  4556 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4557 the obtained context from the course of reasoning!  For example:
  4558 
  4559   assume "EX x y. A x & B y"   -- "any previous fact"
  4560   then guess x and y by clarify
  4561 
  4562 This technique is potentially adventurous, depending on the facts and
  4563 proof tools being involved here.
  4564 
  4565 * Isar: known facts from the proof context may be specified as literal
  4566 propositions, using ASCII back-quote syntax.  This works wherever
  4567 named facts used to be allowed so far, in proof commands, proof
  4568 methods, attributes etc.  Literal facts are retrieved from the context
  4569 according to unification of type and term parameters.  For example,
  4570 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4571 theorems in the current context, then these are valid literal facts:
  4572 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4573 
  4574 There is also a proof method "fact" which does the same composition
  4575 for explicit goal states, e.g. the following proof texts coincide with
  4576 certain special cases of literal facts:
  4577 
  4578   have "A" by fact                 ==  note `A`
  4579   have "A ==> B" by fact           ==  note `A ==> B`
  4580   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4581   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4582 
  4583 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4584 outer syntax.  Thus symbolic identifiers may be used without
  4585 additional white space in declarations like this: ``assume *: A''.
  4586 
  4587 * Isar: 'print_facts' prints all local facts of the current context,
  4588 both named and unnamed ones.
  4589 
  4590 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4591 
  4592   def x == "t" and y == "u"
  4593 
  4594 * Isar: added command 'unfolding', which is structurally similar to
  4595 'using', but affects both the goal state and facts by unfolding given
  4596 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4597 'unfolded' attribute may be replaced by first-class proof text.
  4598 
  4599 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4600 and command 'unfolding' now all support object-level equalities
  4601 (potentially conditional).  The underlying notion of rewrite rule is
  4602 analogous to the 'rule_format' attribute, but *not* that of the
  4603 Simplifier (which is usually more generous).
  4604 
  4605 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4606 premises of a theorem by n. Useful in conjunction with drule.
  4607 
  4608 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4609 method expression within a sandbox consisting of the first N
  4610 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4611 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4612 simplifies all new goals that emerge from applying rule foo to the
  4613 originally first one.
  4614 
  4615 * Isar: schematic goals are no longer restricted to higher-order
  4616 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4617 expected.
  4618 
  4619 * Isar: the conclusion of a long theorem statement is now either
  4620 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4621 (essentially a disjunction of cases with local parameters and
  4622 assumptions).  The latter allows to express general elimination rules
  4623 adequately; in this notation common elimination rules look like this:
  4624 
  4625   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4626     assumes "EX x. P x"
  4627     obtains x where "P x"
  4628 
  4629   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4630     assumes "A & B"
  4631     obtains A and B
  4632 
  4633   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4634     assumes "A | B"
  4635     obtains
  4636       A
  4637     | B
  4638 
  4639 The subsequent classical rules even refer to the formal "thesis"
  4640 explicitly:
  4641 
  4642   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4643     obtains "~ thesis"
  4644 
  4645   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4646     obtains "thesis ==> something"
  4647 
  4648 The actual proof of an 'obtains' statement is analogous to that of the
  4649 Isar proof element 'obtain', only that there may be several cases.
  4650 Optional case names may be specified in parentheses; these will be
  4651 available both in the present proof and as annotations in the
  4652 resulting rule, for later use with the 'cases' method (cf. attribute
  4653 case_names).
  4654 
  4655 * Isar: the assumptions of a long theorem statement are available as
  4656 "assms" fact in the proof context.  This is more appropriate than the
  4657 (historical) "prems", which refers to all assumptions of the current
  4658 context, including those from the target locale, proof body etc.
  4659 
  4660 * Isar: 'print_statement' prints theorems from the current theory or
  4661 proof context in long statement form, according to the syntax of a
  4662 top-level lemma.
  4663 
  4664 * Isar: 'obtain' takes an optional case name for the local context
  4665 introduction rule (default "that").
  4666 
  4667 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4668 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4669 to occur.
  4670 
  4671 * Pure: syntax "CONST name" produces a fully internalized constant
  4672 according to the current context.  This is particularly useful for
  4673 syntax translations that should refer to internal constant
  4674 representations independently of name spaces.
  4675 
  4676 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4677 instead of "FOO ". This allows multiple binder declarations to coexist
  4678 in the same context.  INCOMPATIBILITY.
  4679 
  4680 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4681 primitive that also works in a locale context (both for constants and
  4682 fixed variables). Type declaration and internal syntactic representation
  4683 of given constants retrieved from the context. Likewise, the
  4684 'no_notation' command allows to remove given syntax annotations from the
  4685 current context.
  4686 
  4687 * Isar/locales: new derived specification elements 'axiomatization',
  4688 'definition', 'abbreviation', which support type-inference, admit
  4689 object-level specifications (equality, equivalence).  See also the
  4690 isar-ref manual.  Examples:
  4691 
  4692   axiomatization
  4693     eq  (infix "===" 50) where
  4694     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4695 
  4696   definition "f x y = x + y + 1"
  4697   definition g where "g x = f x x"
  4698 
  4699   abbreviation
  4700     neq  (infix "=!=" 50) where
  4701     "x =!= y == ~ (x === y)"
  4702 
  4703 These specifications may be also used in a locale context.  Then the
  4704 constants being introduced depend on certain fixed parameters, and the
  4705 constant name is qualified by the locale base name.  An internal
  4706 abbreviation takes care for convenient input and output, making the
  4707 parameters implicit and using the original short name.  See also
  4708 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4709 entities from a monomorphic theory.
  4710 
  4711 Presently, abbreviations are only available 'in' a target locale, but
  4712 not inherited by general import expressions.  Also note that
  4713 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4714 'translations' in common applications.  The "no_abbrevs" print mode
  4715 prevents folding of abbreviations in term output.
  4716 
  4717 Concrete syntax is attached to specified constants in internal form,
  4718 independently of name spaces.  The parse tree representation is
  4719 slightly different -- use 'notation' instead of raw 'syntax', and
  4720 'translations' with explicit "CONST" markup to accommodate this.
  4721 
  4722 * Pure/Isar: unified syntax for new-style specification mechanisms
  4723 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4724 full type inference and dummy patterns ("_").  For example:
  4725 
  4726   definition "K x _ = x"
  4727 
  4728   inductive conj for A B
  4729   where "A ==> B ==> conj A B"
  4730 
  4731 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4732 the current context.  Print mode "no_abbrevs" prevents inversion of
  4733 abbreviations on output.
  4734 
  4735 * Isar/locales: improved parameter handling: use of locales "var" and
  4736 "struct" no longer necessary; - parameter renamings are no longer
  4737 required to be injective.  For example, this allows to define
  4738 endomorphisms as locale endom = homom mult mult h.
  4739 
  4740 * Isar/locales: changed the way locales with predicates are defined.
  4741 Instead of accumulating the specification, the imported expression is
  4742 now an interpretation.  INCOMPATIBILITY: different normal form of
  4743 locale expressions.  In particular, in interpretations of locales with
  4744 predicates, goals repesenting already interpreted fragments are not
  4745 removed automatically.  Use methods `intro_locales' and
  4746 `unfold_locales'; see below.
  4747 
  4748 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4749 provide backward reasoning on locales predicates.  The methods are
  4750 aware of interpretations and discharge corresponding goals.
  4751 `intro_locales' is less aggressive then `unfold_locales' and does not
  4752 unfold predicates to assumptions.
  4753 
  4754 * Isar/locales: the order in which locale fragments are accumulated
  4755 has changed.  This enables to override declarations from fragments due
  4756 to interpretations -- for example, unwanted simp rules.
  4757 
  4758 * Isar/locales: interpretation in theories and proof contexts has been
  4759 extended.  One may now specify (and prove) equations, which are
  4760 unfolded in interpreted theorems.  This is useful for replacing
  4761 defined concepts (constants depending on locale parameters) by
  4762 concepts already existing in the target context.  Example:
  4763 
  4764   interpretation partial_order ["op <= :: [int, int] => bool"]
  4765     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4766 
  4767 Typically, the constant `partial_order.less' is created by a
  4768 definition specification element in the context of locale
  4769 partial_order.
  4770 
  4771 * Method "induct": improved internal context management to support
  4772 local fixes and defines on-the-fly. Thus explicit meta-level
  4773 connectives !!  and ==> are rarely required anymore in inductive goals
  4774 (using object-logic connectives for this purpose has been long
  4775 obsolete anyway). Common proof patterns are explained in
  4776 src/HOL/Induct/Common_Patterns.thy, see also
  4777 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4778 examples.
  4779 
  4780 * Method "induct": improved handling of simultaneous goals. Instead of
  4781 introducing object-level conjunction, the statement is now split into
  4782 several conclusions, while the corresponding symbolic cases are nested
  4783 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4784 see src/HOL/Induct/Common_Patterns.thy, for example.
  4785 
  4786 * Method "induct": mutual induction rules are now specified as a list
  4787 of rule sharing the same induction cases. HOL packages usually provide
  4788 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4789 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4790 mutual induction rules differently, i.e. like this:
  4791 
  4792   (induct rule: foo_bar.inducts)
  4793   (induct set: foo bar)
  4794   (induct pred: foo bar)
  4795   (induct type: foo bar)
  4796 
  4797 The ML function ProjectRule.projections turns old-style rules into the
  4798 new format.
  4799 
  4800 * Method "coinduct": dual of induction, see
  4801 src/HOL/Library/Coinductive_List.thy for various examples.
  4802 
  4803 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4804 considered a legacy feature.
  4805 
  4806 * Attribute "symmetric" produces result with standardized schematic
  4807 variables (index 0).  Potential INCOMPATIBILITY.
  4808 
  4809 * Simplifier: by default the simplifier trace only shows top level
  4810 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4811 default. Thus there is less danger of being flooded by the trace. The
  4812 trace indicates where parts have been suppressed.
  4813   
  4814 * Provers/classical: removed obsolete classical version of elim_format
  4815 attribute; classical elim/dest rules are now treated uniformly when
  4816 manipulating the claset.
  4817 
  4818 * Provers/classical: stricter checks to ensure that supplied intro,
  4819 dest and elim rules are well-formed; dest and elim rules must have at
  4820 least one premise.
  4821 
  4822 * Provers/classical: attributes dest/elim/intro take an optional
  4823 weight argument for the rule (just as the Pure versions).  Weights are
  4824 ignored by automated tools, but determine the search order of single
  4825 rule steps.
  4826 
  4827 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4828 where the body does not mention the bound variable.  Note that dummy
  4829 patterns implicitly depend on their context of bounds, which makes
  4830 "{_. _}" match any set comprehension as expected.  Potential
  4831 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4832 constant "_idtdummy" in the binding position.
  4833 
  4834 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4835 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4836 for example "A -> B" => "Pi A (%_. B)".
  4837 
  4838 * Pure: 'class_deps' command visualizes the subclass relation, using
  4839 the graph browser tool.
  4840 
  4841 * Pure: 'print_theory' now suppresses certain internal declarations by
  4842 default; use '!' option for full details.
  4843 
  4844 
  4845 *** HOL ***
  4846 
  4847 * Method "metis" proves goals by applying the Metis general-purpose
  4848 resolution prover (see also http://gilith.com/software/metis/).
  4849 Examples are in the directory MetisExamples.  WARNING: the
  4850 Isabelle/HOL-Metis integration does not yet work properly with
  4851 multi-threading.
  4852   
  4853 * Command 'sledgehammer' invokes external automatic theorem provers as
  4854 background processes.  It generates calls to the "metis" method if
  4855 successful. These can be pasted into the proof.  Users do not have to
  4856 wait for the automatic provers to return.  WARNING: does not really
  4857 work with multi-threading.
  4858 
  4859 * New "auto_quickcheck" feature tests outermost goal statements for
  4860 potential counter-examples.  Controlled by ML references
  4861 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4862 5000 milliseconds).  Fails silently if statements is outside of
  4863 executable fragment, or any other codgenerator problem occurs.
  4864 
  4865 * New constant "undefined" with axiom "undefined x = undefined".
  4866 
  4867 * Added class "HOL.eq", allowing for code generation with polymorphic
  4868 equality.
  4869 
  4870 * Some renaming of class constants due to canonical name prefixing in
  4871 the new 'class' package:
  4872 
  4873     HOL.abs ~> HOL.abs_class.abs
  4874     HOL.divide ~> HOL.divide_class.divide
  4875     0 ~> HOL.zero_class.zero
  4876     1 ~> HOL.one_class.one
  4877     op + ~> HOL.plus_class.plus
  4878     op - ~> HOL.minus_class.minus
  4879     uminus ~> HOL.minus_class.uminus
  4880     op * ~> HOL.times_class.times
  4881     op < ~> HOL.ord_class.less
  4882     op <= > HOL.ord_class.less_eq
  4883     Nat.power ~> Power.power_class.power
  4884     Nat.size ~> Nat.size_class.size
  4885     Numeral.number_of ~> Numeral.number_class.number_of
  4886     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4887     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4888     Orderings.min ~> Orderings.ord_class.min
  4889     Orderings.max ~> Orderings.ord_class.max
  4890     Divides.op div ~> Divides.div_class.div
  4891     Divides.op mod ~> Divides.div_class.mod
  4892     Divides.op dvd ~> Divides.div_class.dvd
  4893 
  4894 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4895 
  4896 a) User-defined constants using any of the names "plus", "minus",
  4897 "times", "less" or "less_eq". The standard syntax translations for
  4898 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4899 names.
  4900 
  4901 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4902 INCOMPATIBILITY: use more specific names.
  4903 
  4904 c) Permutative equations (e.g. "a + b = b + a")
  4905 Since the change of names also changes the order of terms, permutative
  4906 rewrite rules may get applied in a different order. Experience shows
  4907 that this is rarely the case (only two adaptions in the whole Isabelle
  4908 distribution).  INCOMPATIBILITY: rewrite proofs
  4909 
  4910 d) ML code directly refering to constant names
  4911 This in general only affects hand-written proof tactics, simprocs and
  4912 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4913 Consider using @{const_name} antiquotation.
  4914 
  4915 * New class "default" with associated constant "default".
  4916 
  4917 * Function "sgn" is now overloaded and available on int, real, complex
  4918 (and other numeric types), using class "sgn".  Two possible defs of
  4919 sgn are given as equational assumptions in the classes sgn_if and
  4920 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4921 INCOMPATIBILITY.
  4922 
  4923 * Locale "partial_order" now unified with class "order" (cf. theory
  4924 Orderings), added parameter "less".  INCOMPATIBILITY.
  4925 
  4926 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4927 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4928 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4929 
  4930 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4931 changed order of proof goals in instance proofs.
  4932 
  4933 * The transitivity reasoner for partial and linear orders is set up
  4934 for classes "order" and "linorder".  Instances of the reasoner are available
  4935 in all contexts importing or interpreting the corresponding locales.
  4936 Method "order" invokes the reasoner separately; the reasoner
  4937 is also integrated with the Simplifier as a solver.  Diagnostic
  4938 command 'print_orders' shows the available instances of the reasoner
  4939 in the current context.
  4940 
  4941 * Localized monotonicity predicate in theory "Orderings"; integrated
  4942 lemmas max_of_mono and min_of_mono with this predicate.
  4943 INCOMPATIBILITY.
  4944 
  4945 * Formulation of theorem "dense" changed slightly due to integration
  4946 with new class dense_linear_order.
  4947 
  4948 * Uniform lattice theory development in HOL.
  4949 
  4950     constants "meet" and "join" now named "inf" and "sup"
  4951     constant "Meet" now named "Inf"
  4952 
  4953     classes "meet_semilorder" and "join_semilorder" now named
  4954       "lower_semilattice" and "upper_semilattice"
  4955     class "lorder" now named "lattice"
  4956     class "comp_lat" now named "complete_lattice"
  4957 
  4958     Instantiation of lattice classes allows explicit definitions
  4959     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4960 
  4961   INCOMPATIBILITY.  Theorem renames:
  4962 
  4963     meet_left_le            ~> inf_le1
  4964     meet_right_le           ~> inf_le2
  4965     join_left_le            ~> sup_ge1
  4966     join_right_le           ~> sup_ge2
  4967     meet_join_le            ~> inf_sup_ord
  4968     le_meetI                ~> le_infI
  4969     join_leI                ~> le_supI
  4970     le_meet                 ~> le_inf_iff
  4971     le_join                 ~> ge_sup_conv
  4972     meet_idempotent         ~> inf_idem
  4973     join_idempotent         ~> sup_idem
  4974     meet_comm               ~> inf_commute
  4975     join_comm               ~> sup_commute
  4976     meet_leI1               ~> le_infI1
  4977     meet_leI2               ~> le_infI2
  4978     le_joinI1               ~> le_supI1
  4979     le_joinI2               ~> le_supI2
  4980     meet_assoc              ~> inf_assoc
  4981     join_assoc              ~> sup_assoc
  4982     meet_left_comm          ~> inf_left_commute
  4983     meet_left_idempotent    ~> inf_left_idem
  4984     join_left_comm          ~> sup_left_commute
  4985     join_left_idempotent    ~> sup_left_idem
  4986     meet_aci                ~> inf_aci
  4987     join_aci                ~> sup_aci
  4988     le_def_meet             ~> le_iff_inf
  4989     le_def_join             ~> le_iff_sup
  4990     join_absorp2            ~> sup_absorb2
  4991     join_absorp1            ~> sup_absorb1
  4992     meet_absorp1            ~> inf_absorb1
  4993     meet_absorp2            ~> inf_absorb2
  4994     meet_join_absorp        ~> inf_sup_absorb
  4995     join_meet_absorp        ~> sup_inf_absorb
  4996     distrib_join_le         ~> distrib_sup_le
  4997     distrib_meet_le         ~> distrib_inf_le
  4998 
  4999     add_meet_distrib_left   ~> add_inf_distrib_left
  5000     add_join_distrib_left   ~> add_sup_distrib_left
  5001     is_join_neg_meet        ~> is_join_neg_inf
  5002     is_meet_neg_join        ~> is_meet_neg_sup
  5003     add_meet_distrib_right  ~> add_inf_distrib_right
  5004     add_join_distrib_right  ~> add_sup_distrib_right
  5005     add_meet_join_distribs  ~> add_sup_inf_distribs
  5006     join_eq_neg_meet        ~> sup_eq_neg_inf
  5007     meet_eq_neg_join        ~> inf_eq_neg_sup
  5008     add_eq_meet_join        ~> add_eq_inf_sup
  5009     meet_0_imp_0            ~> inf_0_imp_0
  5010     join_0_imp_0            ~> sup_0_imp_0
  5011     meet_0_eq_0             ~> inf_0_eq_0
  5012     join_0_eq_0             ~> sup_0_eq_0
  5013     neg_meet_eq_join        ~> neg_inf_eq_sup
  5014     neg_join_eq_meet        ~> neg_sup_eq_inf
  5015     join_eq_if              ~> sup_eq_if
  5016 
  5017     mono_meet               ~> mono_inf
  5018     mono_join               ~> mono_sup
  5019     meet_bool_eq            ~> inf_bool_eq
  5020     join_bool_eq            ~> sup_bool_eq
  5021     meet_fun_eq             ~> inf_fun_eq
  5022     join_fun_eq             ~> sup_fun_eq
  5023     meet_set_eq             ~> inf_set_eq
  5024     join_set_eq             ~> sup_set_eq
  5025     meet1_iff               ~> inf1_iff
  5026     meet2_iff               ~> inf2_iff
  5027     meet1I                  ~> inf1I
  5028     meet2I                  ~> inf2I
  5029     meet1D1                 ~> inf1D1
  5030     meet2D1                 ~> inf2D1
  5031     meet1D2                 ~> inf1D2
  5032     meet2D2                 ~> inf2D2
  5033     meet1E                  ~> inf1E
  5034     meet2E                  ~> inf2E
  5035     join1_iff               ~> sup1_iff
  5036     join2_iff               ~> sup2_iff
  5037     join1I1                 ~> sup1I1
  5038     join2I1                 ~> sup2I1
  5039     join1I1                 ~> sup1I1
  5040     join2I2                 ~> sup1I2
  5041     join1CI                 ~> sup1CI
  5042     join2CI                 ~> sup2CI
  5043     join1E                  ~> sup1E
  5044     join2E                  ~> sup2E
  5045 
  5046     is_meet_Meet            ~> is_meet_Inf
  5047     Meet_bool_def           ~> Inf_bool_def
  5048     Meet_fun_def            ~> Inf_fun_def
  5049     Meet_greatest           ~> Inf_greatest
  5050     Meet_lower              ~> Inf_lower
  5051     Meet_set_def            ~> Inf_set_def
  5052 
  5053     Sup_def                 ~> Sup_Inf
  5054     Sup_bool_eq             ~> Sup_bool_def
  5055     Sup_fun_eq              ~> Sup_fun_def
  5056     Sup_set_eq              ~> Sup_set_def
  5057 
  5058     listsp_meetI            ~> listsp_infI
  5059     listsp_meet_eq          ~> listsp_inf_eq
  5060 
  5061     meet_min                ~> inf_min
  5062     join_max                ~> sup_max
  5063 
  5064 * Added syntactic class "size"; overloaded constant "size" now has
  5065 type "'a::size ==> bool"
  5066 
  5067 * Internal reorganisation of `size' of datatypes: size theorems
  5068 "foo.size" are no longer subsumed by "foo.simps" (but are still
  5069 simplification rules by default!); theorems "prod.size" now named
  5070 "*.size".
  5071 
  5072 * Class "div" now inherits from class "times" rather than "type".
  5073 INCOMPATIBILITY.
  5074 
  5075 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  5076 Linorder etc.  have disappeared; operations defined in terms of
  5077 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  5078 
  5079 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  5080 
  5081 * HOL-Word: New extensive library and type for generic, fixed size
  5082 machine words, with arithemtic, bit-wise, shifting and rotating
  5083 operations, reflection into int, nat, and bool lists, automation for
  5084 linear arithmetic (by automatic reflection into nat or int), including
  5085 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  5086 arithmetic type classes, supporting automatic simplification of
  5087 numerals on all operations.
  5088 
  5089 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  5090 
  5091 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  5092 
  5093 * Code generator library theories:
  5094   - Code_Integer represents HOL integers by big integer literals in target
  5095     languages.
  5096   - Code_Char represents HOL characters by character literals in target
  5097     languages.
  5098   - Code_Char_chr like Code_Char, but also offers treatment of character
  5099     codes; includes Code_Integer.
  5100   - Executable_Set allows to generate code for finite sets using lists.
  5101   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  5102     denominator).
  5103   - Executable_Real implements a subset of real numbers, namly those
  5104     representable by rational numbers.
  5105   - Efficient_Nat implements natural numbers by integers, which in general will
  5106     result in higher efficency; pattern matching with 0/Suc is eliminated;
  5107     includes Code_Integer.
  5108   - Code_Index provides an additional datatype index which is mapped to
  5109     target-language built-in integers.
  5110   - Code_Message provides an additional datatype message_string which is isomorphic to
  5111     strings; messages are mapped to target-language strings.
  5112 
  5113 * New package for inductive predicates
  5114 
  5115   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  5116 
  5117     inductive
  5118       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5119       for z_1 :: U_1 and ... and z_n :: U_m
  5120     where
  5121       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5122     | ...
  5123 
  5124   with full support for type-inference, rather than
  5125 
  5126     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5127 
  5128     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5129     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5130 
  5131     inductive "s z_1 ... z_m"
  5132     intros
  5133       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5134       ...
  5135 
  5136   For backward compatibility, there is a wrapper allowing inductive
  5137   sets to be defined with the new package via
  5138 
  5139     inductive_set
  5140       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5141       for z_1 :: U_1 and ... and z_n :: U_m
  5142     where
  5143       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5144     | ...
  5145 
  5146   or
  5147 
  5148     inductive_set
  5149       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5150       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5151       for z_1 :: U_1 and ... and z_n :: U_m
  5152     where
  5153       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5154     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5155     | ...
  5156 
  5157   if the additional syntax "p ..." is required.
  5158 
  5159   Numerous examples can be found in the subdirectories src/HOL/Auth,
  5160   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  5161 
  5162   INCOMPATIBILITIES:
  5163 
  5164   - Since declaration and definition of inductive sets or predicates
  5165     is no longer separated, abbreviations involving the newly
  5166     introduced sets or predicates must be specified together with the
  5167     introduction rules after the 'where' keyword (see above), rather
  5168     than before the actual inductive definition.
  5169 
  5170   - The variables in induction and elimination rules are now
  5171     quantified in the order of their occurrence in the introduction
  5172     rules, rather than in alphabetical order. Since this may break
  5173     some proofs, these proofs either have to be repaired, e.g. by
  5174     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  5175     statements of the form
  5176 
  5177       case (rule_i a_i_1 ... a_i_{k_i})
  5178 
  5179     or the old order of quantification has to be restored by explicitly adding
  5180     meta-level quantifiers in the introduction rules, i.e.
  5181 
  5182       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  5183 
  5184   - The format of the elimination rules is now
  5185 
  5186       p z_1 ... z_m x_1 ... x_n ==>
  5187         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5188         ==> ... ==> P
  5189 
  5190     for predicates and
  5191 
  5192       (x_1, ..., x_n) : s z_1 ... z_m ==>
  5193         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5194         ==> ... ==> P
  5195 
  5196     for sets rather than
  5197 
  5198       x : s z_1 ... z_m ==>
  5199         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  5200         ==> ... ==> P
  5201 
  5202     This may require terms in goals to be expanded to n-tuples
  5203     (e.g. using case_tac or simplification with the split_paired_all
  5204     rule) before the above elimination rule is applicable.
  5205 
  5206   - The elimination or case analysis rules for (mutually) inductive
  5207     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  5208     list of rules "p_1_..._p_k.elims" is no longer available.
  5209 
  5210 * New package "function"/"fun" for general recursive functions,
  5211 supporting mutual and nested recursion, definitions in local contexts,
  5212 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  5213 for small examples, and the separate tutorial on the function
  5214 package. The old recdef "package" is still available as before, but
  5215 users are encouraged to use the new package.
  5216 
  5217 * Method "lexicographic_order" automatically synthesizes termination
  5218 relations as lexicographic combinations of size measures. 
  5219 
  5220 * Case-expressions allow arbitrary constructor-patterns (including
  5221 "_") and take their order into account, like in functional
  5222 programming.  Internally, this is translated into nested
  5223 case-expressions; missing cases are added and mapped to the predefined
  5224 constant "undefined". In complicated cases printing may no longer show
  5225 the original input but the internal form. Lambda-abstractions allow
  5226 the same form of pattern matching: "% pat1 => e1 | ..." is an
  5227 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  5228 variable.
  5229 
  5230 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  5231 is an abbreviation for "of_nat :: nat => int". The simplification
  5232 rules for "of_nat" have been changed to work like "int" did
  5233 previously.  Potential INCOMPATIBILITY:
  5234   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  5235   - of_nat_diff and of_nat_mult are no longer default simp rules
  5236 
  5237 * Method "algebra" solves polynomial equations over (semi)rings using
  5238 Groebner bases. The (semi)ring structure is defined by locales and the
  5239 tool setup depends on that generic context. Installing the method for
  5240 a specific type involves instantiating the locale and possibly adding
  5241 declarations for computation on the coefficients.  The method is
  5242 already instantiated for natural numbers and for the axiomatic class
  5243 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  5244 CALCULEMUS 2007 for the general principles underlying this
  5245 architecture of context-aware proof-tools.
  5246 
  5247 * Method "ferrack" implements quantifier elimination over
  5248 special-purpose dense linear orders using locales (analogous to
  5249 "algebra"). The method is already installed for class
  5250 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  5251 rat, etc.
  5252 
  5253 * Former constant "List.op @" now named "List.append".  Use ML
  5254 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  5255 circumvent possible incompatibilities when working on ML level.
  5256 
  5257 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  5258 
  5259 * New function listsum :: 'a list => 'a for arbitrary monoids.
  5260 Special syntax: "SUM x <- xs. f x" (and latex variants)
  5261 
  5262 * New syntax for Haskell-like list comprehension (input only), eg.
  5263 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  5264 
  5265 * The special syntax for function "filter" has changed from [x :
  5266 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  5267 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  5268 
  5269 * [a..b] is now defined for arbitrary linear orders.  It used to be
  5270 defined on nat only, as an abbreviation for [a..<Suc b]
  5271 INCOMPATIBILITY.
  5272 
  5273 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  5274 
  5275 * New functions "sorted" and "sort" in src/HOL/List.thy.
  5276 
  5277 * New lemma collection field_simps (an extension of ring_simps) for
  5278 manipulating (in)equations involving division. Multiplies with all
  5279 denominators that can be proved to be non-zero (in equations) or
  5280 positive/negative (in inequations).
  5281 
  5282 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  5283 have been improved and renamed to ring_simps, group_simps and
  5284 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  5285 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  5286 
  5287 * Theory Library/Commutative_Ring: switched from recdef to function
  5288 package; constants add, mul, pow now curried.  Infix syntax for
  5289 algebraic operations.
  5290 
  5291 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  5292 INCOMPATIBILITY.
  5293 
  5294 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  5295 INCOMPATIBILITY.
  5296 
  5297 * HOL/records: generalised field-update to take a function on the
  5298 field rather than the new value: r(|A := x|) is translated to A_update
  5299 (K x) r The K-combinator that is internally used is called K_record.
  5300 INCOMPATIBILITY: Usage of the plain update functions has to be
  5301 adapted.
  5302  
  5303 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  5304 * x = 0, which are required for a semiring.  Richer structures do not
  5305 inherit from semiring_0 anymore, because this property is a theorem
  5306 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  5307 there is more to prove, but this is mostly trivial.
  5308 
  5309 * Class "recpower" is generalized to arbitrary monoids, not just
  5310 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  5311 commutativity or semiring properties additionally.
  5312 
  5313 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  5314 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  5315 better use 'abbreviation'.
  5316 
  5317 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  5318 
  5319 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  5320 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  5321 significant changes for setting up numeral syntax for types:
  5322   - New constants Numeral.pred and Numeral.succ instead
  5323       of former Numeral.bin_pred and Numeral.bin_succ.
  5324   - Use integer operations instead of bin_add, bin_mult and so on.
  5325   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  5326   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  5327 
  5328 See src/HOL/Integ/IntArith.thy for an example setup.
  5329 
  5330 * Command 'normal_form' computes the normal form of a term that may
  5331 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  5332 produces ``[b, c, a]'' (without proof).  This command is suitable for
  5333 heavy-duty computations because the functions are compiled to ML
  5334 first.  Correspondingly, a method "normalization" is provided.  See
  5335 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  5336 
  5337 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  5338 25 like -->); output depends on the "iff" print_mode, the default is
  5339 "A = B" (with priority 50).
  5340 
  5341 * Relations less (<) and less_eq (<=) are also available on type bool.
  5342 Modified syntax to disallow nesting without explicit parentheses,
  5343 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  5344 INCOMPATIBILITY.
  5345 
  5346 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  5347 
  5348 * Relation composition operator "op O" now has precedence 75 and binds
  5349 stronger than union and intersection. INCOMPATIBILITY.
  5350 
  5351 * The old set interval syntax "{m..n(}" (and relatives) has been
  5352 removed.  Use "{m..<n}" (and relatives) instead.
  5353 
  5354 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  5355 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  5356 ``declare [[simproc del: neq]]''.
  5357 
  5358 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  5359 True/False.
  5360 
  5361 * Theorem Cons_eq_map_conv no longer declared as "simp".
  5362 
  5363 * Theorem setsum_mult renamed to setsum_right_distrib.
  5364 
  5365 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  5366 ``rule'' method.
  5367 
  5368 * Reimplemented methods "sat" and "satx", with several improvements:
  5369 goals no longer need to be stated as "<prems> ==> False", equivalences
  5370 (i.e. "=" on type bool) are handled, variable names of the form
  5371 "lit_<n>" are no longer reserved, significant speedup.
  5372 
  5373 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  5374 zChaff is still supported as well.
  5375 
  5376 * 'inductive' and 'datatype': provide projections of mutual rules,
  5377 bundled as foo_bar.inducts;
  5378 
  5379 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  5380 Library.
  5381 
  5382 * Library: moved theory Accessible_Part to main HOL.
  5383 
  5384 * Library: added theory Coinductive_List of potentially infinite lists
  5385 as greatest fixed-point.
  5386 
  5387 * Library: added theory AssocList which implements (finite) maps as
  5388 association lists.
  5389 
  5390 * Method "evaluation" solves goals (i.e. a boolean expression)
  5391 efficiently by compiling it to ML.  The goal is "proved" (via an
  5392 oracle) if it evaluates to True.
  5393 
  5394 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  5395 also when invoked by the simplifier.  This results in the Simplifier
  5396 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  5397 Configuration option fast_arith_split_limit=0 recovers the old
  5398 behavior.
  5399 
  5400 * Support for hex (0x20) and binary (0b1001) numerals.
  5401 
  5402 * New method: reify eqs (t), where eqs are equations for an
  5403 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  5404 parameter, computes a term s::'b and a list xs::'a list and proves the
  5405 theorem I xs s = t. This is also known as reification or quoting. The
  5406 resulting theorem is applied to the subgoal to substitute t with I xs
  5407 s.  If t is omitted, the subgoal itself is reified.
  5408 
  5409 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  5410 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  5411 where f is supposed to be a computable function (in the sense of code
  5412 generattion). The method uses reify to compute s and xs as above then
  5413 applies corr_thm and uses normalization by evaluation to "prove" f s =
  5414 r and finally gets the theorem t = r, which is again applied to the
  5415 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  5416 
  5417 * Reflection: Automatic reification now handels binding, an example is
  5418 available in src/HOL/ex/ReflectionEx.thy
  5419 
  5420 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  5421 command 'statespace' that is similar to 'record', but introduces an
  5422 abstract specification based on the locale infrastructure instead of
  5423 HOL types.  This leads to extra flexibility in composing state spaces,
  5424 in particular multiple inheritance and renaming of components.
  5425 
  5426 
  5427 *** HOL-Complex ***
  5428 
  5429 * Hyperreal: Functions root and sqrt are now defined on negative real
  5430 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  5431 Nonnegativity side conditions have been removed from many lemmas, so
  5432 that more subgoals may now be solved by simplification; potential
  5433 INCOMPATIBILITY.
  5434 
  5435 * Real: new type classes formalize real normed vector spaces and
  5436 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  5437 and norm :: 'a => real.
  5438 
  5439 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  5440 reals into other types. The overloaded constant Reals :: 'a set is now
  5441 defined as range of_real; potential INCOMPATIBILITY.
  5442 
  5443 * Real: proper support for ML code generation, including 'quickcheck'.
  5444 Reals are implemented as arbitrary precision rationals.
  5445 
  5446 * Hyperreal: Several constants that previously worked only for the
  5447 reals have been generalized, so they now work over arbitrary vector
  5448 spaces. Type annotations may need to be added in some cases; potential
  5449 INCOMPATIBILITY.
  5450 
  5451   Infinitesimal  :: ('a::real_normed_vector) star set
  5452   HFinite        :: ('a::real_normed_vector) star set
  5453   HInfinite      :: ('a::real_normed_vector) star set
  5454   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5455   monad          :: ('a::real_normed_vector) star => 'a star set
  5456   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5457   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5458   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5459   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5460   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5461   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5462   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5463   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5464   sgn            :: 'a::real_normed_vector => 'a
  5465   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5466 
  5467 * Complex: Some complex-specific constants are now abbreviations for
  5468 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5469 hnorm.  Other constants have been entirely removed in favor of the
  5470 polymorphic versions (INCOMPATIBILITY):
  5471 
  5472   approx        <-- capprox
  5473   HFinite       <-- CFinite
  5474   HInfinite     <-- CInfinite
  5475   Infinitesimal <-- CInfinitesimal
  5476   monad         <-- cmonad
  5477   galaxy        <-- cgalaxy
  5478   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5479   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5480   (ns)deriv     <-- (ns)cderiv
  5481 
  5482 
  5483 *** HOL-Algebra ***
  5484 
  5485 * Formalisation of ideals and the quotient construction over rings.
  5486 
  5487 * Order and lattice theory no longer based on records.
  5488 INCOMPATIBILITY.
  5489 
  5490 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5491 greatest_closed.  INCOMPATIBILITY.
  5492 
  5493 * Method algebra is now set up via an attribute.  For examples see
  5494 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5495 of algebraic structures.
  5496 
  5497 * Renamed theory CRing to Ring.
  5498 
  5499 
  5500 *** HOL-Nominal ***
  5501 
  5502 * Substantial, yet incomplete support for nominal datatypes (binding
  5503 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5504 src/HOL/Nominal/Examples.  Prospective users should consult
  5505 http://isabelle.in.tum.de/nominal/
  5506 
  5507 
  5508 *** ML ***
  5509 
  5510 * ML basics: just one true type int, which coincides with IntInf.int
  5511 (even on SML/NJ).
  5512 
  5513 * ML within Isar: antiquotations allow to embed statically-checked
  5514 formal entities in the source, referring to the context available at
  5515 compile-time.  For example:
  5516 
  5517 ML {* @{sort "{zero,one}"} *}
  5518 ML {* @{typ "'a => 'b"} *}
  5519 ML {* @{term "%x. x"} *}
  5520 ML {* @{prop "x == y"} *}
  5521 ML {* @{ctyp "'a => 'b"} *}
  5522 ML {* @{cterm "%x. x"} *}
  5523 ML {* @{cprop "x == y"} *}
  5524 ML {* @{thm asm_rl} *}
  5525 ML {* @{thms asm_rl} *}
  5526 ML {* @{type_name c} *}
  5527 ML {* @{type_syntax c} *}
  5528 ML {* @{const_name c} *}
  5529 ML {* @{const_syntax c} *}
  5530 ML {* @{context} *}
  5531 ML {* @{theory} *}
  5532 ML {* @{theory Pure} *}
  5533 ML {* @{theory_ref} *}
  5534 ML {* @{theory_ref Pure} *}
  5535 ML {* @{simpset} *}
  5536 ML {* @{claset} *}
  5537 ML {* @{clasimpset} *}
  5538 
  5539 The same works for sources being ``used'' within an Isar context.
  5540 
  5541 * ML in Isar: improved error reporting; extra verbosity with
  5542 ML_Context.trace enabled.
  5543 
  5544 * Pure/General/table.ML: the join operations now works via exceptions
  5545 DUP/SAME instead of type option. This is simpler in simple cases, and
  5546 admits slightly more efficient complex applications.
  5547 
  5548 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5549 use Context.generic instead of just theory.
  5550 
  5551 * Pure: datatype Context.generic joins theory/Proof.context and
  5552 provides some facilities for code that works in either kind of
  5553 context, notably GenericDataFun for uniform theory and proof data.
  5554 
  5555 * Pure: simplified internal attribute type, which is now always
  5556 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5557 local (Proof.context) attributes have been discontinued, while
  5558 minimizing code duplication. Thm.rule_attribute and
  5559 Thm.declaration_attribute build canonical attributes; see also structure
  5560 Context for further operations on Context.generic, notably
  5561 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5562 declarations and definitions.
  5563 
  5564 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5565 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5566 init only required for impure data. INCOMPATIBILITY: empty really need
  5567 to be empty (no dependencies on theory content!)
  5568 
  5569 * Pure/kernel: consts certification ignores sort constraints given in
  5570 signature declarations. (This information is not relevant to the
  5571 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5572 potential INCOMPATIBILITY.
  5573 
  5574 * Pure: axiomatic type classes are now purely definitional, with
  5575 explicit proofs of class axioms and super class relations performed
  5576 internally. See Pure/axclass.ML for the main internal interfaces --
  5577 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5578 AxClass.axiomatize_class/classrel/arity supersede
  5579 Sign.add_classes/classrel/arities.
  5580 
  5581 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5582 global/local versions on theory vs. Proof.context have been
  5583 discontinued; Attrib.syntax and Method.syntax have been adapted
  5584 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5585 attributes, methods, etc.
  5586 
  5587 * Pure: several functions of signature "... -> theory -> theory * ..."
  5588 have been reoriented to "... -> theory -> ... * theory" in order to
  5589 allow natural usage in combination with the ||>, ||>>, |-> and
  5590 fold_map combinators.
  5591 
  5592 * Pure: official theorem names (closed derivations) and additional
  5593 comments (tags) are now strictly separate.  Name hints -- which are
  5594 maintained as tags -- may be attached any time without affecting the
  5595 derivation.
  5596 
  5597 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5598 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5599 achieve the old behaviour.
  5600 
  5601 * Pure: the "Goal" constant is now called "prop", supporting a
  5602 slightly more general idea of ``protecting'' meta-level rule
  5603 statements.
  5604 
  5605 * Pure: Logic.(un)varify only works in a global context, which is now
  5606 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5607 Logic.legacy_(un)varify as temporary workaround.
  5608 
  5609 * Pure: structure Name provides scalable operations for generating
  5610 internal variable names, notably Name.variants etc.  This replaces
  5611 some popular functions from term.ML:
  5612 
  5613   Term.variant		->  Name.variant
  5614   Term.variantlist	->  Name.variant_list
  5615   Term.invent_names	->  Name.invent_list
  5616 
  5617 Note that low-level renaming rarely occurs in new code -- operations
  5618 from structure Variable are used instead (see below).
  5619 
  5620 * Pure: structure Variable provides fundamental operations for proper
  5621 treatment of fixed/schematic variables in a context.  For example,
  5622 Variable.import introduces fixes for schematics of given facts and
  5623 Variable.export reverses the effect (up to renaming) -- this replaces
  5624 various freeze_thaw operations.
  5625 
  5626 * Pure: structure Goal provides simple interfaces for
  5627 init/conclude/finish and tactical prove operations (replacing former
  5628 Tactic.prove).  Goal.prove is the canonical way to prove results
  5629 within a given context; Goal.prove_global is a degraded version for
  5630 theory level goals, including a global Drule.standard.  Note that
  5631 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5632 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5633 in a locale context).
  5634 
  5635 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5636 and type checking (Syntax.check_term etc.), with common combinations
  5637 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5638 which are considered legacy and await removal.
  5639 
  5640 * Pure/Syntax: generic interfaces for type unchecking
  5641 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5642 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5643 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5644 available for convenience, but refer to the very same operations using
  5645 a mere theory instead of a full context.
  5646 
  5647 * Isar: simplified treatment of user-level errors, using exception
  5648 ERROR of string uniformly.  Function error now merely raises ERROR,
  5649 without any side effect on output channels.  The Isar toplevel takes
  5650 care of proper display of ERROR exceptions.  ML code may use plain
  5651 handle/can/try; cat_error may be used to concatenate errors like this:
  5652 
  5653   ... handle ERROR msg => cat_error msg "..."
  5654 
  5655 Toplevel ML code (run directly or through the Isar toplevel) may be
  5656 embedded into the Isar toplevel with exception display/debug like
  5657 this:
  5658 
  5659   Isar.toplevel (fn () => ...)
  5660 
  5661 INCOMPATIBILITY, removed special transform_error facilities, removed
  5662 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5663 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5664 -- use plain ERROR instead.
  5665 
  5666 * Isar: theory setup now has type (theory -> theory), instead of a
  5667 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5668 
  5669 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5670 ProofContext.debug/verbose flags.
  5671 
  5672 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5673 theory before entering a proof state.  Transactions now always see a
  5674 quasi-functional intermediate checkpoint, both in interactive and
  5675 batch mode.
  5676 
  5677 * Isar: simplified interfaces for outer syntax.  Renamed
  5678 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5679 OuterSyntax.add_parsers -- this functionality is now included in
  5680 OuterSyntax.command etc.  INCOMPATIBILITY.
  5681 
  5682 * Simplifier: the simpset of a running simplification process now
  5683 contains a proof context (cf. Simplifier.the_context), which is the
  5684 very context that the initial simpset has been retrieved from (by
  5685 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5686 (solver, looper etc.) may depend on arbitrary proof data.
  5687 
  5688 * Simplifier.inherit_context inherits the proof context (plus the
  5689 local bounds) of the current simplification process; any simproc
  5690 etc. that calls the Simplifier recursively should do this!  Removed
  5691 former Simplifier.inherit_bounds, which is already included here --
  5692 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5693 specify an explicit context using Simplifier.context/theory_context.
  5694 
  5695 * Simplifier/Classical Reasoner: more abstract interfaces
  5696 change_simpset/claset for modifying the simpset/claset reference of a
  5697 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5698 INCOMPATIBILITY.
  5699 
  5700 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5701 "Trueprop" etc.
  5702 
  5703 
  5704 *** System ***
  5705 
  5706 * settings: the default heap location within ISABELLE_HOME_USER now
  5707 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5708 Isabelle installations.
  5709 
  5710 * isabelle-process: option -S (secure mode) disables some critical
  5711 operations, notably runtime compilation and evaluation of ML source
  5712 code.
  5713 
  5714 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5715 
  5716 * Support for parallel execution, using native multicore support of
  5717 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5718 independent theories, according to the given theory header
  5719 specifications. The maximum number of worker threads is specified via
  5720 usedir option -M or the "max-threads" setting in Proof General. A
  5721 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5722 to 6 on a 8-core machine.  User-code needs to observe certain
  5723 guidelines for thread-safe programming, see appendix A in the Isar
  5724 Implementation manual.
  5725 
  5726 
  5727 
  5728 New in Isabelle2005 (October 2005)
  5729 ----------------------------------
  5730 
  5731 *** General ***
  5732 
  5733 * Theory headers: the new header syntax for Isar theories is
  5734 
  5735   theory <name>
  5736   imports <theory1> ... <theoryN>
  5737   uses <file1> ... <fileM>
  5738   begin
  5739 
  5740 where the 'uses' part is optional.  The previous syntax
  5741 
  5742   theory <name> = <theory1> + ... + <theoryN>:
  5743 
  5744 will disappear in the next release.  Use isatool fixheaders to convert
  5745 existing theory files.  Note that there is no change in ancient
  5746 non-Isar theories now, but these will disappear soon.
  5747 
  5748 * Theory loader: parent theories can now also be referred to via
  5749 relative and absolute paths.
  5750 
  5751 * Command 'find_theorems' searches for a list of criteria instead of a
  5752 list of constants. Known criteria are: intro, elim, dest, name:string,
  5753 simp:term, and any term. Criteria can be preceded by '-' to select
  5754 theorems that do not match. Intro, elim, dest select theorems that
  5755 match the current goal, name:s selects theorems whose fully qualified
  5756 name contain s, and simp:term selects all simplification rules whose
  5757 lhs match term.  Any other term is interpreted as pattern and selects
  5758 all theorems matching the pattern. Available in ProofGeneral under
  5759 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5760 
  5761   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5762 
  5763 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5764 matching the current goal as introduction rule and not having "HOL."
  5765 in their name (i.e. not being defined in theory HOL).
  5766 
  5767 * Command 'thms_containing' has been discontinued in favour of
  5768 'find_theorems'; INCOMPATIBILITY.
  5769 
  5770 * Communication with Proof General is now 8bit clean, which means that
  5771 Unicode text in UTF-8 encoding may be used within theory texts (both
  5772 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5773 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5774 
  5775   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5776   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5777 
  5778 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5779 Classical Reasoner.  Typical big applications run around 2 times
  5780 faster.
  5781 
  5782 
  5783 *** Document preparation ***
  5784 
  5785 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5786 of raw sources.  Only those symbols that do not require additional
  5787 LaTeX packages (depending on comments in isabellesym.sty) are
  5788 displayed properly, everything else is left verbatim.  isatool display
  5789 and isatool print are used as front ends (these are subject to the
  5790 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5791 
  5792 * Command tags control specific markup of certain regions of text,
  5793 notably folding and hiding.  Predefined tags include "theory" (for
  5794 theory begin and end), "proof" for proof commands, and "ML" for
  5795 commands involving ML code; the additional tags "visible" and
  5796 "invisible" are unused by default.  Users may give explicit tag
  5797 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5798 interpretation of tags is determined by the LaTeX job during document
  5799 preparation: see option -V of isatool usedir, or options -n and -t of
  5800 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5801 \isadroptag.
  5802 
  5803 Several document versions may be produced at the same time via isatool
  5804 usedir (the generated index.html will link all of them).  Typical
  5805 specifications include ''-V document=theory,proof,ML'' to present
  5806 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5807 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5808 these parts without any formal replacement text.  The Isabelle site
  5809 default settings produce ''document'' and ''outline'' versions as
  5810 specified above.
  5811 
  5812 * Several new antiquotations:
  5813 
  5814   @{term_type term} prints a term with its type annotated;
  5815 
  5816   @{typeof term} prints the type of a term;
  5817 
  5818   @{const const} is the same as @{term const}, but checks that the
  5819   argument is a known logical constant;
  5820 
  5821   @{term_style style term} and @{thm_style style thm} print a term or
  5822   theorem applying a "style" to it
  5823 
  5824   @{ML text}
  5825 
  5826 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5827 definitions, equations, inequations etc., 'concl' printing only the
  5828 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5829 to print the specified premise.  TermStyle.add_style provides an ML
  5830 interface for introducing further styles.  See also the "LaTeX Sugar"
  5831 document practical applications.  The ML antiquotation prints
  5832 type-checked ML expressions verbatim.
  5833 
  5834 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5835 and 'text' support optional locale specification '(in loc)', which
  5836 specifies the default context for interpreting antiquotations.  For
  5837 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5838 
  5839 * Option 'locale=NAME' of antiquotations specifies an alternative
  5840 context interpreting the subsequent argument.  For example: @{thm
  5841 [locale=lattice] inf_assoc}.
  5842 
  5843 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5844 a proof context.
  5845 
  5846 * Proper output of antiquotations for theory commands involving a
  5847 proof context (such as 'locale' or 'theorem (in loc) ...').
  5848 
  5849 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5850 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5851 
  5852 * isatool usedir: new option -C (default true) controls whether option
  5853 -D should include a copy of the original document directory; -C false
  5854 prevents unwanted effects such as copying of administrative CVS data.
  5855 
  5856 
  5857 *** Pure ***
  5858 
  5859 * Considerably improved version of 'constdefs' command.  Now performs
  5860 automatic type-inference of declared constants; additional support for
  5861 local structure declarations (cf. locales and HOL records), see also
  5862 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5863 sequential dependencies of definitions within a single 'constdefs'
  5864 section; moreover, the declared name needs to be an identifier.  If
  5865 all fails, consider to fall back on 'consts' and 'defs' separately.
  5866 
  5867 * Improved indexed syntax and implicit structures.  First of all,
  5868 indexed syntax provides a notational device for subscripted
  5869 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5870 expressions.  Secondly, in a local context with structure
  5871 declarations, number indexes \<^sub>n or the empty index (default
  5872 number 1) refer to a certain fixed variable implicitly; option
  5873 show_structs controls printing of implicit structures.  Typical
  5874 applications of these concepts involve record types and locales.
  5875 
  5876 * New command 'no_syntax' removes grammar declarations (and
  5877 translations) resulting from the given syntax specification, which is
  5878 interpreted in the same manner as for the 'syntax' command.
  5879 
  5880 * 'Advanced' translation functions (parse_translation etc.) may depend
  5881 on the signature of the theory context being presently used for
  5882 parsing/printing, see also isar-ref manual.
  5883 
  5884 * Improved 'oracle' command provides a type-safe interface to turn an
  5885 ML expression of type theory -> T -> term into a primitive rule of
  5886 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5887 is already included here); see also FOL/ex/IffExample.thy;
  5888 INCOMPATIBILITY.
  5889 
  5890 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5891 before); "cI" is no longer bound, use "c.intro" instead.
  5892 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5893 axclasses vs. locales.
  5894 
  5895 * Improved internal renaming of symbolic identifiers -- attach primes
  5896 instead of base 26 numbers.
  5897 
  5898 * New flag show_question_marks controls printing of leading question
  5899 marks in schematic variable names.
  5900 
  5901 * In schematic variable names, *any* symbol following \<^isub> or
  5902 \<^isup> is now treated as part of the base name.  For example, the
  5903 following works without printing of awkward ".0" indexes:
  5904 
  5905   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5906     by simp
  5907 
  5908 * Inner syntax includes (*(*nested*) comments*).
  5909 
  5910 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5911 annotations as "(00...)".
  5912 
  5913 * Clear separation of logical types and nonterminals, where the latter
  5914 may only occur in 'syntax' specifications or type abbreviations.
  5915 Before that distinction was only partially implemented via type class
  5916 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5917 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5918 exotic syntax specifications may require further adaption
  5919 (e.g. Cube/Cube.thy).
  5920 
  5921 * Removed obsolete type class "logic", use the top sort {} instead.
  5922 Note that non-logical types should be declared as 'nonterminals'
  5923 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5924 specifications.
  5925 
  5926 * Attributes 'induct' and 'cases': type or set names may now be
  5927 locally fixed variables as well.
  5928 
  5929 * Simplifier: can now control the depth to which conditional rewriting
  5930 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5931 Limit.
  5932 
  5933 * Simplifier: simplification procedures may now take the current
  5934 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5935 interface), which is very useful for calling the Simplifier
  5936 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5937 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5938 low-level mk_simproc no longer applies Logic.varify internally, to
  5939 allow for use in a context of fixed variables.
  5940 
  5941 * thin_tac now works even if the assumption being deleted contains !!
  5942 or ==>.  More generally, erule now works even if the major premise of
  5943 the elimination rule contains !! or ==>.
  5944 
  5945 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5946 
  5947 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5948 from Pure, which contains all common declarations already.  Both
  5949 theories are defined via plain Isabelle/Isar .thy files.
  5950 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5951 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5952 use isatool fixcpure to adapt your theory and ML sources.
  5953 
  5954 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5955 selections of theorems in named facts via index ranges.
  5956 
  5957 * 'print_theorems': in theory mode, really print the difference
  5958 wrt. the last state (works for interactive theory development only),
  5959 in proof mode print all local facts (cf. 'print_facts');
  5960 
  5961 * 'hide': option '(open)' hides only base names.
  5962 
  5963 * More efficient treatment of intermediate checkpoints in interactive
  5964 theory development.
  5965 
  5966 * Code generator is now invoked via code_module (incremental code
  5967 generation) and code_library (modular code generation, ML structures
  5968 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5969 must be quoted when used as identifiers.
  5970 
  5971 * New 'value' command for reading, evaluating and printing terms using
  5972 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5973 quoted when used as identifier.
  5974 
  5975 
  5976 *** Locales ***
  5977 
  5978 * New commands for the interpretation of locale expressions in
  5979 theories (1), locales (2) and proof contexts (3).  These generate
  5980 proof obligations from the expression specification.  After the
  5981 obligations have been discharged, theorems of the expression are added
  5982 to the theory, target locale or proof context.  The synopsis of the
  5983 commands is a follows:
  5984 
  5985   (1) interpretation expr inst
  5986   (2) interpretation target < expr
  5987   (3) interpret expr inst
  5988 
  5989 Interpretation in theories and proof contexts require a parameter
  5990 instantiation of terms from the current context.  This is applied to
  5991 specifications and theorems of the interpreted expression.
  5992 Interpretation in locales only permits parameter renaming through the
  5993 locale expression.  Interpretation is smart in that interpretations
  5994 that are active already do not occur in proof obligations, neither are
  5995 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5996 inspect active interpretations of a particular locale.  For details,
  5997 see the Isar Reference manual.  Examples can be found in
  5998 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5999 
  6000 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  6001 'interpret' instead.
  6002 
  6003 * New context element 'constrains' for adding type constraints to
  6004 parameters.
  6005 
  6006 * Context expressions: renaming of parameters with syntax
  6007 redeclaration.
  6008 
  6009 * Locale declaration: 'includes' disallowed.
  6010 
  6011 * Proper static binding of attribute syntax -- i.e. types / terms /
  6012 facts mentioned as arguments are always those of the locale definition
  6013 context, independently of the context of later invocations.  Moreover,
  6014 locale operations (renaming and type / term instantiation) are applied
  6015 to attribute arguments as expected.
  6016 
  6017 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  6018 actual attributes; rare situations may require Attrib.attribute to
  6019 embed those attributes into Attrib.src that lack concrete syntax.
  6020 Attribute implementations need to cooperate properly with the static
  6021 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  6022 Attrib.XXX_thm etc. already do the right thing without further
  6023 intervention.  Only unusual applications -- such as "where" or "of"
  6024 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  6025 on the context and the facts involved -- may have to assign parsed
  6026 values to argument tokens explicitly.
  6027 
  6028 * Changed parameter management in theorem generation for long goal
  6029 statements with 'includes'.  INCOMPATIBILITY: produces a different
  6030 theorem statement in rare situations.
  6031 
  6032 * Locale inspection command 'print_locale' omits notes elements.  Use
  6033 'print_locale!' to have them included in the output.
  6034 
  6035 
  6036 *** Provers ***
  6037 
  6038 * Provers/hypsubst.ML: improved version of the subst method, for
  6039 single-step rewriting: it now works in bound variable contexts. New is
  6040 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  6041 rewrite a different subterm than the original subst method, which is
  6042 still available as 'simplesubst'.
  6043 
  6044 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  6045 and quasi orders.
  6046 
  6047 * Provers/trancl.ML: new transitivity reasoner for transitive and
  6048 reflexive-transitive closure of relations.
  6049 
  6050 * Provers/blast.ML: new reference depth_limit to make blast's depth
  6051 limit (previously hard-coded with a value of 20) user-definable.
  6052 
  6053 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  6054 is peformed already.  Object-logics merely need to finish their
  6055 initial simpset configuration as before.  INCOMPATIBILITY.
  6056 
  6057 
  6058 *** HOL ***
  6059 
  6060 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  6061 
  6062   syntax (epsilon)
  6063     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  6064 
  6065 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  6066 and x-symbol; use option '-m epsilon' to get it actually printed.
  6067 Moreover, the mathematically important symbolic identifier \<epsilon>
  6068 becomes available as variable, constant etc.  INCOMPATIBILITY,
  6069 
  6070 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  6071 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  6072 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  6073 support corresponding Isar calculations.
  6074 
  6075 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  6076 instead of ":".
  6077 
  6078 * theory SetInterval: changed the syntax for open intervals:
  6079 
  6080   Old       New
  6081   {..n(}    {..<n}
  6082   {)n..}    {n<..}
  6083   {m..n(}   {m..<n}
  6084   {)m..n}   {m<..n}
  6085   {)m..n(}  {m<..<n}
  6086 
  6087 The old syntax is still supported but will disappear in the next
  6088 release.  For conversion use the following Emacs search and replace
  6089 patterns (these are not perfect but work quite well):
  6090 
  6091   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  6092   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  6093 
  6094 * Theory Commutative_Ring (in Library): method comm_ring for proving
  6095 equalities in commutative rings; method 'algebra' provides a generic
  6096 interface.
  6097 
  6098 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  6099 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  6100 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  6101 be a tuple pattern.
  6102 
  6103 Some new syntax forms are available:
  6104 
  6105   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  6106   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  6107   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  6108   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  6109 
  6110 The latter form "\<Sum>x < k. e" used to be based on a separate
  6111 function "Summation", which has been discontinued.
  6112 
  6113 * theory Finite_Set: in structured induction proofs, the insert case
  6114 is now 'case (insert x F)' instead of the old counterintuitive 'case
  6115 (insert F x)'.
  6116 
  6117 * The 'refute' command has been extended to support a much larger
  6118 fragment of HOL, including axiomatic type classes, constdefs and
  6119 typedefs, inductive datatypes and recursion.
  6120 
  6121 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  6122 Requires zChaff with proof generation to be installed.  See
  6123 HOL/ex/SAT_Examples.thy for examples.
  6124 
  6125 * Datatype induction via method 'induct' now preserves the name of the
  6126 induction variable. For example, when proving P(xs::'a list) by
  6127 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  6128 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  6129 in unstructured proof scripts.
  6130 
  6131 * Reworked implementation of records.  Improved scalability for
  6132 records with many fields, avoiding performance problems for type
  6133 inference. Records are no longer composed of nested field types, but
  6134 of nested extension types. Therefore the record type only grows linear
  6135 in the number of extensions and not in the number of fields.  The
  6136 top-level (users) view on records is preserved.  Potential
  6137 INCOMPATIBILITY only in strange cases, where the theory depends on the
  6138 old record representation. The type generated for a record is called
  6139 <record_name>_ext_type.
  6140 
  6141 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  6142 proofs triggered by a record definition or a simproc (if
  6143 quick_and_dirty is enabled).  Definitions of large records can take
  6144 quite long.
  6145 
  6146 New simproc record_upd_simproc for simplification of multiple record
  6147 updates enabled by default.  Moreover, trivial updates are also
  6148 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  6149 occasionally, since simplification is more powerful by default.
  6150 
  6151 * typedef: proper support for polymorphic sets, which contain extra
  6152 type-variables in the term.
  6153 
  6154 * Simplifier: automatically reasons about transitivity chains
  6155 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  6156 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  6157 old proofs break occasionally as simplification may now solve more
  6158 goals than previously.
  6159 
  6160 * Simplifier: converts x <= y into x = y if assumption y <= x is
  6161 present.  Works for all partial orders (class "order"), in particular
  6162 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  6163 just like y <= x.
  6164 
  6165 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  6166 bound variable or a constant then the let is unfolded.  Otherwise
  6167 first a is simplified to b, and then f b is simplified to g. If
  6168 possible we abstract b from g arriving at "let x = b in h x",
  6169 otherwise we unfold the let and arrive at g.  The simproc can be
  6170 enabled/disabled by the reference use_let_simproc.  Potential
  6171 INCOMPATIBILITY since simplification is more powerful by default.
  6172 
  6173 * Classical reasoning: the meson method now accepts theorems as arguments.
  6174 
  6175 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  6176 jobs to provide advice on the provability of subgoals.
  6177 
  6178 * Theory OrderedGroup and Ring_and_Field: various additions and
  6179 improvements to faciliate calculations involving equalities and
  6180 inequalities.
  6181 
  6182 The following theorems have been eliminated or modified
  6183 (INCOMPATIBILITY):
  6184 
  6185   abs_eq             now named abs_of_nonneg
  6186   abs_of_ge_0        now named abs_of_nonneg
  6187   abs_minus_eq       now named abs_of_nonpos
  6188   imp_abs_id         now named abs_of_nonneg
  6189   imp_abs_neg_id     now named abs_of_nonpos
  6190   mult_pos           now named mult_pos_pos
  6191   mult_pos_le        now named mult_nonneg_nonneg
  6192   mult_pos_neg_le    now named mult_nonneg_nonpos
  6193   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  6194   mult_neg           now named mult_neg_neg
  6195   mult_neg_le        now named mult_nonpos_nonpos
  6196 
  6197 * The following lemmas in Ring_and_Field have been added to the simplifier:
  6198      
  6199      zero_le_square
  6200      not_square_less_zero 
  6201 
  6202   The following lemmas have been deleted from Real/RealPow:
  6203   
  6204      realpow_zero_zero
  6205      realpow_two
  6206      realpow_less
  6207      zero_le_power
  6208      realpow_two_le
  6209      abs_realpow_two
  6210      realpow_two_abs     
  6211 
  6212 * Theory Parity: added rules for simplifying exponents.
  6213 
  6214 * Theory List:
  6215 
  6216 The following theorems have been eliminated or modified
  6217 (INCOMPATIBILITY):
  6218 
  6219   list_all_Nil       now named list_all.simps(1)
  6220   list_all_Cons      now named list_all.simps(2)
  6221   list_all_conv      now named list_all_iff
  6222   set_mem_eq         now named mem_iff
  6223 
  6224 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  6225 asymptotic "big O" calculations.  See the notes in BigO.thy.
  6226 
  6227 
  6228 *** HOL-Complex ***
  6229 
  6230 * Theory RealDef: better support for embedding natural numbers and
  6231 integers in the reals.
  6232 
  6233 The following theorems have been eliminated or modified
  6234 (INCOMPATIBILITY):
  6235 
  6236   exp_ge_add_one_self  now requires no hypotheses
  6237   real_of_int_add      reversed direction of equality (use [symmetric])
  6238   real_of_int_minus    reversed direction of equality (use [symmetric])
  6239   real_of_int_diff     reversed direction of equality (use [symmetric])
  6240   real_of_int_mult     reversed direction of equality (use [symmetric])
  6241 
  6242 * Theory RComplete: expanded support for floor and ceiling functions.
  6243 
  6244 * Theory Ln is new, with properties of the natural logarithm
  6245 
  6246 * Hyperreal: There is a new type constructor "star" for making
  6247 nonstandard types.  The old type names are now type synonyms:
  6248 
  6249   hypreal = real star
  6250   hypnat = nat star
  6251   hcomplex = complex star
  6252 
  6253 * Hyperreal: Many groups of similarly-defined constants have been
  6254 replaced by polymorphic versions (INCOMPATIBILITY):
  6255 
  6256   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  6257 
  6258   starset      <-- starsetNat, starsetC
  6259   *s*          <-- *sNat*, *sc*
  6260   starset_n    <-- starsetNat_n, starsetC_n
  6261   *sn*         <-- *sNatn*, *scn*
  6262   InternalSets <-- InternalNatSets, InternalCSets
  6263 
  6264   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  6265   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  6266   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  6267   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  6268   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  6269 
  6270 * Hyperreal: Many type-specific theorems have been removed in favor of
  6271 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  6272 
  6273   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  6274   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  6275   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  6276   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  6277   right_minus <-- hypreal_add_minus
  6278   left_minus <-- {hypreal,hcomplex}_add_minus_left
  6279   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  6280   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  6281   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  6282   mult_1_right <-- hcomplex_mult_one_right
  6283   mult_zero_left <-- hcomplex_mult_zero_left
  6284   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  6285   right_distrib <-- hypnat_add_mult_distrib2
  6286   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  6287   right_inverse <-- hypreal_mult_inverse
  6288   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  6289   order_refl <-- {hypreal,hypnat}_le_refl
  6290   order_trans <-- {hypreal,hypnat}_le_trans
  6291   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  6292   order_less_le <-- {hypreal,hypnat}_less_le
  6293   linorder_linear <-- {hypreal,hypnat}_le_linear
  6294   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  6295   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  6296   add_nonneg_nonneg <-- hypreal_le_add_order
  6297 
  6298 * Hyperreal: Separate theorems having to do with type-specific
  6299 versions of constants have been merged into theorems that apply to the
  6300 new polymorphic constants (INCOMPATIBILITY):
  6301 
  6302   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  6303   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  6304   STAR_Un <-- {STAR,NatStar,STARC}_Un
  6305   STAR_Int <-- {STAR,NatStar,STARC}_Int
  6306   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  6307   STAR_subset <-- {STAR,NatStar,STARC}_subset
  6308   STAR_mem <-- {STAR,NatStar,STARC}_mem
  6309   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  6310   STAR_diff <-- {STAR,STARC}_diff
  6311   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  6312     STARC_hcomplex_of_complex}_image_subset
  6313   starset_n_Un <-- starset{Nat,C}_n_Un
  6314   starset_n_Int <-- starset{Nat,C}_n_Int
  6315   starset_n_Compl <-- starset{Nat,C}_n_Compl
  6316   starset_n_diff <-- starset{Nat,C}_n_diff
  6317   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  6318   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  6319   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  6320   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  6321   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  6322   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  6323   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  6324   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  6325   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  6326   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  6327   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  6328   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  6329   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  6330   starfun_diff <-- starfun{C,RC,CR}_diff
  6331   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  6332   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  6333   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  6334   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  6335   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  6336   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  6337   starfun_Id <-- starfunC_Id
  6338   starfun_approx <-- starfun{Nat,CR}_approx
  6339   starfun_capprox <-- starfun{C,RC}_capprox
  6340   starfun_abs <-- starfunNat_rabs
  6341   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  6342   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  6343   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  6344   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  6345   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  6346   starfun_add_approx <-- starfunCR_add_approx
  6347   starfun_inverse_inverse <-- starfunC_inverse_inverse
  6348   starfun_divide <-- starfun{C,CR,RC}_divide
  6349   starfun_n <-- starfun{Nat,C}_n
  6350   starfun_n_mult <-- starfun{Nat,C}_n_mult
  6351   starfun_n_add <-- starfun{Nat,C}_n_add
  6352   starfun_n_add_minus <-- starfunNat_n_add_minus
  6353   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  6354   starfun_n_minus <-- starfun{Nat,C}_n_minus
  6355   starfun_n_eq <-- starfun{Nat,C}_n_eq
  6356 
  6357   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  6358   star_n_minus <-- {hypreal,hcomplex}_minus
  6359   star_n_diff <-- {hypreal,hcomplex}_diff
  6360   star_n_mult <-- {hypreal,hcomplex}_mult
  6361   star_n_inverse <-- {hypreal,hcomplex}_inverse
  6362   star_n_le <-- {hypreal,hypnat}_le
  6363   star_n_less <-- {hypreal,hypnat}_less
  6364   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  6365   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  6366   star_n_abs <-- hypreal_hrabs
  6367   star_n_divide <-- hcomplex_divide
  6368 
  6369   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  6370   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  6371   star_of_diff <-- hypreal_of_real_diff
  6372   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  6373   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  6374   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  6375   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  6376   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  6377   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  6378   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  6379   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  6380   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  6381   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  6382   star_of_number_of <-- {hypreal,hcomplex}_number_of
  6383   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  6384   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  6385   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  6386   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  6387   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  6388   star_of_power <-- hypreal_of_real_power
  6389   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  6390 
  6391 * Hyperreal: new method "transfer" that implements the transfer
  6392 principle of nonstandard analysis. With a subgoal that mentions
  6393 nonstandard types like "'a star", the command "apply transfer"
  6394 replaces it with an equivalent one that mentions only standard types.
  6395 To be successful, all free variables must have standard types; non-
  6396 standard variables must have explicit universal quantifiers.
  6397 
  6398 * Hyperreal: A theory of Taylor series.
  6399 
  6400 
  6401 *** HOLCF ***
  6402 
  6403 * Discontinued special version of 'constdefs' (which used to support
  6404 continuous functions) in favor of the general Pure one with full
  6405 type-inference.
  6406 
  6407 * New simplification procedure for solving continuity conditions; it
  6408 is much faster on terms with many nested lambda abstractions (cubic
  6409 instead of exponential time).
  6410 
  6411 * New syntax for domain package: selector names are now optional.
  6412 Parentheses should be omitted unless argument is lazy, for example:
  6413 
  6414   domain 'a stream = cons "'a" (lazy "'a stream")
  6415 
  6416 * New command 'fixrec' for defining recursive functions with pattern
  6417 matching; defining multiple functions with mutual recursion is also
  6418 supported.  Patterns may include the constants cpair, spair, up, sinl,
  6419 sinr, or any data constructor defined by the domain package. The given
  6420 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  6421 syntax and examples.
  6422 
  6423 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  6424 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  6425 but the proof obligation additionally includes an admissibility
  6426 requirement. The packages generate instances of class cpo or pcpo,
  6427 with continuity and strictness theorems for Rep and Abs.
  6428 
  6429 * HOLCF: Many theorems have been renamed according to a more standard naming
  6430 scheme (INCOMPATIBILITY):
  6431 
  6432   foo_inject:  "foo$x = foo$y ==> x = y"
  6433   foo_eq:      "(foo$x = foo$y) = (x = y)"
  6434   foo_less:    "(foo$x << foo$y) = (x << y)"
  6435   foo_strict:  "foo$UU = UU"
  6436   foo_defined: "... ==> foo$x ~= UU"
  6437   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  6438 
  6439 
  6440 *** ZF ***
  6441 
  6442 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  6443 including the First Isomorphism Theorem (on quotienting by the kernel
  6444 of a homomorphism).
  6445 
  6446 * ZF/Simplifier: install second copy of type solver that actually
  6447 makes use of TC rules declared to Isar proof contexts (or locales);
  6448 the old version is still required for ML proof scripts.
  6449 
  6450 
  6451 *** Cube ***
  6452 
  6453 * Converted to Isar theory format; use locales instead of axiomatic
  6454 theories.
  6455 
  6456 
  6457 *** ML ***
  6458 
  6459 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6460 for ||>, ||>>, |>>,
  6461 
  6462 * Pure/library.ML no longer defines its own option datatype, but uses
  6463 that of the SML basis, which has constructors NONE and SOME instead of
  6464 None and Some, as well as exception Option.Option instead of OPTION.
  6465 The functions the, if_none, is_some, is_none have been adapted
  6466 accordingly, while Option.map replaces apsome.
  6467 
  6468 * Pure/library.ML: the exception LIST has been given up in favour of
  6469 the standard exceptions Empty and Subscript, as well as
  6470 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6471 superceded by the standard hd and tl functions etc.
  6472 
  6473 A number of basic list functions are no longer exported to the ML
  6474 toplevel, as they are variants of predefined functions.  The following
  6475 suggests how one can translate existing code:
  6476 
  6477     rev_append xs ys = List.revAppend (xs, ys)
  6478     nth_elem (i, xs) = List.nth (xs, i)
  6479     last_elem xs = List.last xs
  6480     flat xss = List.concat xss
  6481     seq fs = List.app fs
  6482     partition P xs = List.partition P xs
  6483     mapfilter f xs = List.mapPartial f xs
  6484 
  6485 * Pure/library.ML: several combinators for linear functional
  6486 transformations, notably reverse application and composition:
  6487 
  6488   x |> f                f #> g
  6489   (x, y) |-> f          f #-> g
  6490 
  6491 * Pure/library.ML: introduced/changed precedence of infix operators:
  6492 
  6493   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6494   infix 2 ?;
  6495   infix 3 o oo ooo oooo;
  6496   infix 4 ~~ upto downto;
  6497 
  6498 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6499 infix operators.
  6500 
  6501 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6502 fold_map support linear functional transformations and nesting.  For
  6503 example:
  6504 
  6505   fold f [x1, ..., xN] y =
  6506     y |> f x1 |> ... |> f xN
  6507 
  6508   (fold o fold) f [xs1, ..., xsN] y =
  6509     y |> fold f xs1 |> ... |> fold f xsN
  6510 
  6511   fold f [x1, ..., xN] =
  6512     f x1 #> ... #> f xN
  6513 
  6514   (fold o fold) f [xs1, ..., xsN] =
  6515     fold f xs1 #> ... #> fold f xsN
  6516 
  6517 * Pure/library.ML: the following selectors on type 'a option are
  6518 available:
  6519 
  6520   the:               'a option -> 'a  (*partial*)
  6521   these:             'a option -> 'a  where 'a = 'b list
  6522   the_default: 'a -> 'a option -> 'a
  6523   the_list:          'a option -> 'a list
  6524 
  6525 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6526 basic operations for association lists, following natural argument
  6527 order; moreover the explicit equality predicate passed here avoids
  6528 potentially expensive polymorphic runtime equality checks.
  6529 The old functions may be expressed as follows:
  6530 
  6531   assoc = uncurry (AList.lookup (op =))
  6532   assocs = these oo AList.lookup (op =)
  6533   overwrite = uncurry (AList.update (op =)) o swap
  6534 
  6535 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6536 
  6537   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6538   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6539 
  6540 replacing make_keylist and keyfilter (occassionally used)
  6541 Naive rewrites:
  6542 
  6543   make_keylist = AList.make
  6544   keyfilter = AList.find (op =)
  6545 
  6546 * eq_fst and eq_snd now take explicit equality parameter, thus
  6547   avoiding eqtypes. Naive rewrites:
  6548 
  6549     eq_fst = eq_fst (op =)
  6550     eq_snd = eq_snd (op =)
  6551 
  6552 * Removed deprecated apl and apr (rarely used).
  6553   Naive rewrites:
  6554 
  6555     apl (n, op) =>>= curry op n
  6556     apr (op, m) =>>= fn n => op (n, m)
  6557 
  6558 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6559 provides a reasonably efficient light-weight implementation of sets as
  6560 lists.
  6561 
  6562 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6563 few new operations; existing lookup and update are now curried to
  6564 follow natural argument order (for use with fold etc.);
  6565 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6566 
  6567 * Pure/General: output via the Isabelle channels of
  6568 writeln/warning/error etc. is now passed through Output.output, with a
  6569 hook for arbitrary transformations depending on the print_mode
  6570 (cf. Output.add_mode -- the first active mode that provides a output
  6571 function wins).  Already formatted output may be embedded into further
  6572 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6573 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6574 accommodate easy composition of diagnostic messages etc.  Programmers
  6575 rarely need to care about Output.output or Output.raw at all, with
  6576 some notable exceptions: Output.output is required when bypassing the
  6577 standard channels (writeln etc.), or in token translations to produce
  6578 properly formatted results; Output.raw is required when capturing
  6579 already output material that will eventually be presented to the user
  6580 a second time.  For the default print mode, both Output.output and
  6581 Output.raw have no effect.
  6582 
  6583 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6584 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6585 cumulative results are displayed at the end of a batch session.
  6586 
  6587 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6588 replaced by File.platform_path and File.shell_path (with appropriate
  6589 hooks).  This provides a clean interface for unusual systems where the
  6590 internal and external process view of file names are different.
  6591 
  6592 * Pure: more efficient orders for basic syntactic entities: added
  6593 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6594 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6595 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6596 orders now -- potential INCOMPATIBILITY for code that depends on a
  6597 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6598 Library.sort_strings on result).
  6599 
  6600 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6601 fold_types traverse types/terms from left to right, observing natural
  6602 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6603 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6604 
  6605 * Pure: name spaces have been refined, with significant changes of the
  6606 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6607 to extern(_table).  The plain name entry path is superceded by a
  6608 general 'naming' context, which also includes the 'policy' to produce
  6609 a fully qualified name and external accesses of a fully qualified
  6610 name; NameSpace.extend is superceded by context dependent
  6611 Sign.declare_name.  Several theory and proof context operations modify
  6612 the naming context.  Especially note Theory.restore_naming and
  6613 ProofContext.restore_naming to get back to a sane state; note that
  6614 Theory.add_path is no longer sufficient to recover from
  6615 Theory.absolute_path in particular.
  6616 
  6617 * Pure: new flags short_names (default false) and unique_names
  6618 (default true) for controlling output of qualified names.  If
  6619 short_names is set, names are printed unqualified.  If unique_names is
  6620 reset, the name prefix is reduced to the minimum required to achieve
  6621 the original result when interning again, even if there is an overlap
  6622 with earlier declarations.
  6623 
  6624 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6625 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6626 (useful for printing error messages).  INCOMPATIBILITY.
  6627 
  6628 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6629 Theory.theory are now identified, referring to the universal
  6630 Context.theory (see Pure/context.ML).  Actual signature and theory
  6631 content is managed as theory data.  The old code and interfaces were
  6632 spread over many files and structures; the new arrangement introduces
  6633 considerable INCOMPATIBILITY to gain more clarity:
  6634 
  6635   Context -- theory management operations (name, identity, inclusion,
  6636     parents, ancestors, merge, etc.), plus generic theory data;
  6637 
  6638   Sign -- logical signature and syntax operations (declaring consts,
  6639     types, etc.), plus certify/read for common entities;
  6640 
  6641   Theory -- logical theory operations (stating axioms, definitions,
  6642     oracles), plus a copy of logical signature operations (consts,
  6643     types, etc.); also a few basic management operations (Theory.copy,
  6644     Theory.merge, etc.)
  6645 
  6646 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6647 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6648 for convenience -- they merely return the theory.
  6649 
  6650 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6651 
  6652 * Pure: the Isar proof context type is already defined early in Pure
  6653 as Context.proof (note that ProofContext.context and Proof.context are
  6654 aliases, where the latter is the preferred name).  This enables other
  6655 Isabelle components to refer to that type even before Isar is present.
  6656 
  6657 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6658 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6659 any of these kinds.  For example, Sign.intern typeK is now
  6660 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6661 Theory.hide_types.  Also note that former
  6662 Theory.hide_classes/types/consts are now
  6663 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6664 internalize their arguments!  INCOMPATIBILITY.
  6665 
  6666 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6667 datatype thmref (with constructors Name and NameSelection) instead of
  6668 plain string -- INCOMPATIBILITY;
  6669 
  6670 * Pure: cases produced by proof methods specify options, where NONE
  6671 means to remove case bindings -- INCOMPATIBILITY in
  6672 (RAW_)METHOD_CASES.
  6673 
  6674 * Pure: the following operations retrieve axioms or theorems from a
  6675 theory node or theory hierarchy, respectively:
  6676 
  6677   Theory.axioms_of: theory -> (string * term) list
  6678   Theory.all_axioms_of: theory -> (string * term) list
  6679   PureThy.thms_of: theory -> (string * thm) list
  6680   PureThy.all_thms_of: theory -> (string * thm) list
  6681 
  6682 * Pure: print_tac now outputs the goal through the trace channel.
  6683 
  6684 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6685 Reference Toplevel.debug (default false) controls detailed printing
  6686 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6687 controls execution profiling -- set to 1 for time and 2 for space
  6688 (both increase the runtime).
  6689 
  6690 * Isar session: The initial use of ROOT.ML is now always timed,
  6691 i.e. the log will show the actual process times, in contrast to the
  6692 elapsed wall-clock time that the outer shell wrapper produces.
  6693 
  6694 * Simplifier: improved handling of bound variables (nameless
  6695 representation, avoid allocating new strings).  Simprocs that invoke
  6696 the Simplifier recursively should use Simplifier.inherit_bounds to
  6697 avoid local name clashes.  Failure to do so produces warnings
  6698 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6699 for further details.
  6700 
  6701 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6702 bindings for all theorems stored within a given theory; this may help
  6703 in porting non-Isar theories to Isar ones, while keeping ML proof
  6704 scripts for the time being.
  6705 
  6706 * ML operator HTML.with_charset specifies the charset begin used for
  6707 generated HTML files.  For example:
  6708 
  6709   HTML.with_charset "utf-8" use_thy "Hebrew";
  6710   HTML.with_charset "utf-8" use_thy "Chinese";
  6711 
  6712 
  6713 *** System ***
  6714 
  6715 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6716 isabelle, isatool etc.).
  6717 
  6718 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6719 isatool doc, isatool mkdir, display_drafts etc.).
  6720 
  6721 * isatool usedir: option -f allows specification of the ML file to be
  6722 used by Isabelle; default is ROOT.ML.
  6723 
  6724 * New isatool version outputs the version identifier of the Isabelle
  6725 distribution being used.
  6726 
  6727 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6728 (containing Boolean satisfiability problems) into Isabelle/HOL
  6729 theories.
  6730 
  6731 
  6732 
  6733 New in Isabelle2004 (April 2004)
  6734 --------------------------------
  6735 
  6736 *** General ***
  6737 
  6738 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6739   Replaces linorder.ML.
  6740 
  6741 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6742   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6743   (\<a>...\<z>), are now considered normal letters, and can therefore
  6744   be used anywhere where an ASCII letter (a...zA...Z) has until
  6745   now. COMPATIBILITY: This obviously changes the parsing of some
  6746   terms, especially where a symbol has been used as a binder, say
  6747   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6748   as an identifier.  Fix it by inserting a space around former
  6749   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6750   existing theory and ML files.
  6751 
  6752 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6753 
  6754 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6755   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6756   a normal (but invisible) letter. For multiple letter subscripts repeat
  6757   \<^isub> like this: x\<^isub>1\<^isub>2.
  6758 
  6759 * Pure: There are now sub-/superscripts that can span more than one
  6760   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6761   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6762   superscript. The new control characters are not identifier parts.
  6763 
  6764 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6765   content of "..." to the latex file instead of \isacntrl... . The "..."
  6766   may consist of any printable characters excluding the end bracket >.
  6767 
  6768 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6769   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6770   declare constants "final", which prevents their being given a definition
  6771   later.  It is useful for constants whose behaviour is fixed axiomatically
  6772   rather than definitionally, such as the meta-logic connectives.
  6773 
  6774 * Pure: 'instance' now handles general arities with general sorts
  6775   (i.e. intersections of classes),
  6776 
  6777 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6778   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6779   It can be changed to alter the colors/layout of generated pages.
  6780 
  6781 
  6782 *** Isar ***
  6783 
  6784 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6785   cut_tac, subgoal_tac and thin_tac:
  6786   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6787     locales are no longer forced to write Isar proof scripts.
  6788     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6789     emulations.
  6790   - INCOMPATIBILITY: names of variables to be instantiated may no
  6791     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6792     This is consistent with the instantiation attribute "where".
  6793 
  6794 * Attributes "where" and "of":
  6795   - Now take type variables of instantiated theorem into account when reading
  6796     the instantiation string.  This fixes a bug that caused instantiated
  6797     theorems to have too special types in some circumstances.
  6798   - "where" permits explicit instantiations of type variables.
  6799 
  6800 * Calculation commands "moreover" and "also" no longer interfere with
  6801   current facts ("this"), admitting arbitrary combinations with "then"
  6802   and derived forms.
  6803 
  6804 * Locales:
  6805   - Goal statements involving the context element "includes" no longer
  6806     generate theorems with internal delta predicates (those ending on
  6807     "_axioms") in the premise.
  6808     Resolve particular premise with <locale>.intro to obtain old form.
  6809   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6810     specification and "includes" elements in goal statement.
  6811   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6812     [intro?] and [elim?] (respectively) by default.
  6813   - Experimental command for instantiation of locales in proof contexts:
  6814         instantiate <label>[<attrs>]: <loc>
  6815     Instantiates locale <loc> and adds all its theorems to the current context
  6816     taking into account their attributes.  Label and attrs are optional
  6817     modifiers, like in theorem declarations.  If present, names of
  6818     instantiated theorems are qualified with <label>, and the attributes
  6819     <attrs> are applied after any attributes these theorems might have already.
  6820       If the locale has assumptions, a chained fact of the form
  6821     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6822     are derived.  The command does not support old-style locales declared
  6823     with "locale (open)".
  6824       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6825 
  6826 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6827   (Isar) contexts.
  6828 
  6829 
  6830 *** HOL ***
  6831 
  6832 * Proof import: new image HOL4 contains the imported library from
  6833   the HOL4 system with about 2500 theorems. It is imported by
  6834   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6835   can be used like any other Isabelle image.  See
  6836   HOL/Import/HOL/README for more information.
  6837 
  6838 * Simplifier:
  6839   - Much improved handling of linear and partial orders.
  6840     Reasoners for linear and partial orders are set up for type classes
  6841     "linorder" and "order" respectively, and are added to the default simpset
  6842     as solvers.  This means that the simplifier can build transitivity chains
  6843     to solve goals from the assumptions.
  6844   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6845     of blast or auto after simplification become unnecessary because the goal
  6846     is solved by simplification already.
  6847 
  6848 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6849     all proved in axiomatic type classes for semirings, rings and fields.
  6850 
  6851 * Numerics:
  6852   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6853     now formalized using the Ring_and_Field theory mentioned above.
  6854   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6855     than before, because now they are set up once in a generic manner.
  6856   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6857     Look for the general versions in Ring_and_Field (and Power if they concern
  6858     exponentiation).
  6859 
  6860 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6861 
  6862 * Records:
  6863   - Record types are now by default printed with their type abbreviation
  6864     instead of the list of all field types. This can be configured via
  6865     the reference "print_record_type_abbr".
  6866   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6867     (not enabled by default).
  6868   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6869     EX x. x = sel r to True (not enabled by default).
  6870   - Tactic "record_split_simp_tac" to split and simplify records added.
  6871 
  6872 * 'specification' command added, allowing for definition by
  6873   specification.  There is also an 'ax_specification' command that
  6874   introduces the new constants axiomatically.
  6875 
  6876 * arith(_tac) is now able to generate counterexamples for reals as well.
  6877 
  6878 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6879 
  6880 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6881   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6882 
  6883 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6884   matrix theory to linear programming.
  6885 
  6886 * Unions and Intersections:
  6887   The latex output syntax of UN and INT has been changed
  6888   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6889   i.e. the index formulae has become a subscript.
  6890   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6891 
  6892 * Unions and Intersections over Intervals:
  6893   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6894   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6895   like in normal math, and corresponding versions for < and for intersection.
  6896 
  6897 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6898   lexicographic dictonary ordering has been added as "lexord".
  6899 
  6900 * ML: the legacy theory structures Int and List have been removed. They had
  6901   conflicted with ML Basis Library structures having the same names.
  6902 
  6903 * 'refute' command added to search for (finite) countermodels.  Only works
  6904   for a fragment of HOL.  The installation of an external SAT solver is
  6905   highly recommended.  See "HOL/Refute.thy" for details.
  6906 
  6907 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6908   formulae under an assignment of free variables to random values.
  6909   In contrast to 'refute', it can deal with inductive datatypes,
  6910   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6911   for examples.
  6912 
  6913 
  6914 *** HOLCF ***
  6915 
  6916 * Streams now come with concatenation and are part of the HOLCF image
  6917 
  6918 
  6919 
  6920 New in Isabelle2003 (May 2003)
  6921 ------------------------------
  6922 
  6923 *** General ***
  6924 
  6925 * Provers/simplifier:
  6926 
  6927   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6928     Assumptions are now subject to complete mutual simplification,
  6929     not just from left to right. The simplifier now preserves
  6930     the order of assumptions.
  6931 
  6932     Potential INCOMPATIBILITY:
  6933 
  6934     -- simp sometimes diverges where the old version did
  6935        not, e.g. invoking simp on the goal
  6936 
  6937         [| P (f x); y = x; f x = f y |] ==> Q
  6938 
  6939        now gives rise to the infinite reduction sequence
  6940 
  6941         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6942 
  6943        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6944        kind of problem.
  6945 
  6946     -- Tactics combining classical reasoner and simplification (such as auto)
  6947        are also affected by this change, because many of them rely on
  6948        simp. They may sometimes diverge as well or yield a different numbers
  6949        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6950        in case of problems. Sometimes subsequent calls to the classical
  6951        reasoner will fail because a preceeding call to the simplifier too
  6952        eagerly simplified the goal, e.g. deleted redundant premises.
  6953 
  6954   - The simplifier trace now shows the names of the applied rewrite rules
  6955 
  6956   - You can limit the number of recursive invocations of the simplifier
  6957     during conditional rewriting (where the simplifie tries to solve the
  6958     conditions before applying the rewrite rule):
  6959     ML "simp_depth_limit := n"
  6960     where n is an integer. Thus you can force termination where previously
  6961     the simplifier would diverge.
  6962 
  6963   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6964 
  6965   - No longer aborts on failed congruence proof.  Instead, the
  6966     congruence is ignored.
  6967 
  6968 * Pure: New generic framework for extracting programs from constructive
  6969   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6970   as HOL/Extraction for some case studies.
  6971 
  6972 * Pure: The main goal of the proof state is no longer shown by default, only
  6973 the subgoals. This behaviour is controlled by a new flag.
  6974    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6975 (ML: Proof.show_main_goal).
  6976 
  6977 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6978 rules whose conclusion matches subgoal 1:
  6979       PG menu: Isabelle/Isar -> Show me -> matching rules
  6980 The rules are ordered by how closely they match the subgoal.
  6981 In particular, rules that solve a subgoal outright are displayed first
  6982 (or rather last, the way they are printed).
  6983 (ML: ProofGeneral.print_intros())
  6984 
  6985 * Pure: New flag trace_unify_fail causes unification to print
  6986 diagnostic information (PG: in trace buffer) when it fails. This is
  6987 useful for figuring out why single step proofs like rule, erule or
  6988 assumption failed.
  6989 
  6990 * Pure: Locale specifications now produce predicate definitions
  6991 according to the body of text (covering assumptions modulo local
  6992 definitions); predicate "loc_axioms" covers newly introduced text,
  6993 while "loc" is cumulative wrt. all included locale expressions; the
  6994 latter view is presented only on export into the global theory
  6995 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6996 on the old view without predicates;
  6997 
  6998 * Pure: predefined locales "var" and "struct" are useful for sharing
  6999 parameters (as in CASL, for example); just specify something like
  7000 ``var x + var y + struct M'' as import;
  7001 
  7002 * Pure: improved thms_containing: proper indexing of facts instead of
  7003 raw theorems; check validity of results wrt. current name space;
  7004 include local facts of proof configuration (also covers active
  7005 locales), cover fixed variables in index; may use "_" in term
  7006 specification; an optional limit for the number of printed facts may
  7007 be given (the default is 40);
  7008 
  7009 * Pure: disallow duplicate fact bindings within new-style theory files
  7010 (batch-mode only);
  7011 
  7012 * Provers: improved induct method: assumptions introduced by case
  7013 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  7014 the goal statement); "foo" still refers to all facts collectively;
  7015 
  7016 * Provers: the function blast.overloaded has been removed: all constants
  7017 are regarded as potentially overloaded, which improves robustness in exchange
  7018 for slight decrease in efficiency;
  7019 
  7020 * Provers/linorder: New generic prover for transitivity reasoning over
  7021 linear orders.  Note: this prover is not efficient!
  7022 
  7023 * Isar: preview of problems to finish 'show' now produce an error
  7024 rather than just a warning (in interactive mode);
  7025 
  7026 
  7027 *** HOL ***
  7028 
  7029 * arith(_tac)
  7030 
  7031  - Produces a counter example if it cannot prove a goal.
  7032    Note that the counter example may be spurious if the goal is not a formula
  7033    of quantifier-free linear arithmetic.
  7034    In ProofGeneral the counter example appears in the trace buffer.
  7035 
  7036  - Knows about div k and mod k where k is a numeral of type nat or int.
  7037 
  7038  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  7039    linear arithmetic fails. This takes account of quantifiers and divisibility.
  7040    Presburger arithmetic can also be called explicitly via presburger(_tac).
  7041 
  7042 * simp's arithmetic capabilities have been enhanced a bit: it now
  7043 takes ~= in premises into account (by performing a case split);
  7044 
  7045 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  7046 are distributed over a sum of terms;
  7047 
  7048 * New tactic "trans_tac" and method "trans" instantiate
  7049 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  7050 "<=", "<" and "=").
  7051 
  7052 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  7053 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  7054 
  7055 * 'typedef' command has new option "open" to suppress the set
  7056 definition;
  7057 
  7058 * functions Min and Max on finite sets have been introduced (theory
  7059 Finite_Set);
  7060 
  7061 * attribute [symmetric] now works for relations as well; it turns
  7062 (x,y) : R^-1 into (y,x) : R, and vice versa;
  7063 
  7064 * induct over a !!-quantified statement (say !!x1..xn):
  7065   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  7066 
  7067 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  7068 %x. None. Warning: empty_def now refers to the previously hidden definition
  7069 of the empty set.
  7070 
  7071 * Algebra: formalization of classical algebra.  Intended as base for
  7072 any algebraic development in Isabelle.  Currently covers group theory
  7073 (up to Sylow's theorem) and ring theory (Universal Property of
  7074 Univariate Polynomials).  Contributions welcome;
  7075 
  7076 * GroupTheory: deleted, since its material has been moved to Algebra;
  7077 
  7078 * Complex: new directory of the complex numbers with numeric constants,
  7079 nonstandard complex numbers, and some complex analysis, standard and
  7080 nonstandard (Jacques Fleuriot);
  7081 
  7082 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  7083 
  7084 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  7085 Fleuriot);
  7086 
  7087 * Real/HahnBanach: updated and adapted to locales;
  7088 
  7089 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  7090 Gray and Kramer);
  7091 
  7092 * UNITY: added the Meier-Sanders theory of progress sets;
  7093 
  7094 * MicroJava: bytecode verifier and lightweight bytecode verifier
  7095 as abstract algorithms, instantiated to the JVM;
  7096 
  7097 * Bali: Java source language formalization. Type system, operational
  7098 semantics, axiomatic semantics. Supported language features:
  7099 classes, interfaces, objects,virtual methods, static methods,
  7100 static/instance fields, arrays, access modifiers, definite
  7101 assignment, exceptions.
  7102 
  7103 
  7104 *** ZF ***
  7105 
  7106 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  7107 universe, etc.);
  7108 
  7109 * Main ZF: virtually all theories converted to new-style format;
  7110 
  7111 
  7112 *** ML ***
  7113 
  7114 * Pure: Tactic.prove provides sane interface for internal proofs;
  7115 omits the infamous "standard" operation, so this is more appropriate
  7116 than prove_goalw_cterm in many situations (e.g. in simprocs);
  7117 
  7118 * Pure: improved error reporting of simprocs;
  7119 
  7120 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  7121 up simprocs;
  7122 
  7123 
  7124 *** Document preparation ***
  7125 
  7126 * uses \par instead of \\ for line breaks in theory text. This may
  7127 shift some page breaks in large documents. To get the old behaviour
  7128 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  7129 
  7130 * minimized dependencies of isabelle.sty and isabellesym.sty on
  7131 other packages
  7132 
  7133 * \<euro> now needs package babel/greek instead of marvosym (which
  7134 broke \Rightarrow)
  7135 
  7136 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  7137 textcomp package)
  7138 
  7139 
  7140 
  7141 New in Isabelle2002 (March 2002)
  7142 --------------------------------
  7143 
  7144 *** Document preparation ***
  7145 
  7146 * greatly simplified document preparation setup, including more
  7147 graceful interpretation of isatool usedir -i/-d/-D options, and more
  7148 instructive isatool mkdir; users should basically be able to get
  7149 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  7150 users may run a separate document processing stage manually like this:
  7151 "isatool usedir -D output HOL Test && isatool document Test/output";
  7152 
  7153 * theory dependency graph may now be incorporated into documents;
  7154 isatool usedir -g true will produce session_graph.eps/.pdf for use
  7155 with \includegraphics of LaTeX;
  7156 
  7157 * proper spacing of consecutive markup elements, especially text
  7158 blocks after section headings;
  7159 
  7160 * support bold style (for single symbols only), input syntax is like
  7161 this: "\<^bold>\<alpha>" or "\<^bold>A";
  7162 
  7163 * \<bullet> is now output as bold \cdot by default, which looks much
  7164 better in printed text;
  7165 
  7166 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  7167 note that these symbols are currently unavailable in Proof General /
  7168 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  7169 
  7170 * isatool latex no longer depends on changed TEXINPUTS, instead
  7171 isatool document copies the Isabelle style files to the target
  7172 location;
  7173 
  7174 
  7175 *** Isar ***
  7176 
  7177 * Pure/Provers: improved proof by cases and induction;
  7178   - 'case' command admits impromptu naming of parameters (such as
  7179     "case (Suc n)");
  7180   - 'induct' method divinates rule instantiation from the inductive
  7181     claim; no longer requires excessive ?P bindings for proper
  7182     instantiation of cases;
  7183   - 'induct' method properly enumerates all possibilities of set/type
  7184     rules; as a consequence facts may be also passed through *type*
  7185     rules without further ado;
  7186   - 'induct' method now derives symbolic cases from the *rulified*
  7187     rule (before it used to rulify cases stemming from the internal
  7188     atomized version); this means that the context of a non-atomic
  7189     statement becomes is included in the hypothesis, avoiding the
  7190     slightly cumbersome show "PROP ?case" form;
  7191   - 'induct' may now use elim-style induction rules without chaining
  7192     facts, using ``missing'' premises from the goal state; this allows
  7193     rules stemming from inductive sets to be applied in unstructured
  7194     scripts, while still benefitting from proper handling of non-atomic
  7195     statements; NB: major inductive premises need to be put first, all
  7196     the rest of the goal is passed through the induction;
  7197   - 'induct' proper support for mutual induction involving non-atomic
  7198     rule statements (uses the new concept of simultaneous goals, see
  7199     below);
  7200   - append all possible rule selections, but only use the first
  7201     success (no backtracking);
  7202   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  7203   - undeclared rule case names default to numbers 1, 2, 3, ...;
  7204   - added 'print_induct_rules' (covered by help item in recent Proof
  7205     General versions);
  7206   - moved induct/cases attributes to Pure, methods to Provers;
  7207   - generic method setup instantiated for FOL and HOL;
  7208 
  7209 * Pure: support multiple simultaneous goal statements, for example
  7210 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  7211 meta-level mechanism, this acts as if several individual goals had
  7212 been stated separately; in particular common proof methods need to be
  7213 repeated in order to cover all claims; note that a single elimination
  7214 step is *not* sufficient to establish the two conjunctions, so this
  7215 fails:
  7216 
  7217   assume "A & B" then have A and B ..   (*".." fails*)
  7218 
  7219 better use "obtain" in situations as above; alternative refer to
  7220 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  7221 
  7222 * Pure: proper integration with ``locales''; unlike the original
  7223 version by Florian Kammller, Isar locales package high-level proof
  7224 contexts rather than raw logical ones (e.g. we admit to include
  7225 attributes everywhere); operations on locales include merge and
  7226 rename; support for implicit arguments (``structures''); simultaneous
  7227 type-inference over imports and text; see also HOL/ex/Locales.thy for
  7228 some examples;
  7229 
  7230 * Pure: the following commands have been ``localized'', supporting a
  7231 target locale specification "(in name)": 'lemma', 'theorem',
  7232 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  7233 stored both within the locale and at the theory level (exported and
  7234 qualified by the locale name);
  7235 
  7236 * Pure: theory goals may now be specified in ``long'' form, with
  7237 ad-hoc contexts consisting of arbitrary locale elements. for example
  7238 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  7239 definitions may be given, too); the result is a meta-level rule with
  7240 the context elements being discharged in the obvious way;
  7241 
  7242 * Pure: new proof command 'using' allows to augment currently used
  7243 facts after a goal statement ('using' is syntactically analogous to
  7244 'apply', but acts on the goal's facts only); this allows chained facts
  7245 to be separated into parts given before and after a claim, as in
  7246 ``from a and b have C using d and e <proof>'';
  7247 
  7248 * Pure: renamed "antecedent" case to "rule_context";
  7249 
  7250 * Pure: new 'judgment' command records explicit information about the
  7251 object-logic embedding (used by several tools internally); no longer
  7252 use hard-wired "Trueprop";
  7253 
  7254 * Pure: added 'corollary' command;
  7255 
  7256 * Pure: fixed 'token_translation' command;
  7257 
  7258 * Pure: removed obsolete 'exported' attribute;
  7259 
  7260 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  7261 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  7262 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  7263 
  7264 * Pure: method 'atomize' presents local goal premises as object-level
  7265 statements (atomic meta-level propositions); setup controlled via
  7266 rewrite rules declarations of 'atomize' attribute; example
  7267 application: 'induct' method with proper rule statements in improper
  7268 proof *scripts*;
  7269 
  7270 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  7271 now consider the syntactic context of assumptions, giving a better
  7272 chance to get type-inference of the arguments right (this is
  7273 especially important for locales);
  7274 
  7275 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  7276 mode;
  7277 
  7278 * Pure/obtain: the formal conclusion "thesis", being marked as
  7279 ``internal'', may no longer be reference directly in the text;
  7280 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  7281 situations;
  7282 
  7283 * Pure: generic 'sym' attribute which declares a rule both as pure
  7284 'elim?' and for the 'symmetric' operation;
  7285 
  7286 * Pure: marginal comments ``--'' may now occur just anywhere in the
  7287 text; the fixed correlation with particular command syntax has been
  7288 discontinued;
  7289 
  7290 * Pure: new method 'rules' is particularly well-suited for proof
  7291 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  7292 but often produces more compact proof terms with less detours;
  7293 
  7294 * Pure/Provers/classical: simplified integration with pure rule
  7295 attributes and methods; the classical "intro?/elim?/dest?"
  7296 declarations coincide with the pure ones; the "rule" method no longer
  7297 includes classically swapped intros; "intro" and "elim" methods no
  7298 longer pick rules from the context; also got rid of ML declarations
  7299 AddXIs/AddXEs/AddXDs; all of this has some potential for
  7300 INCOMPATIBILITY;
  7301 
  7302 * Provers/classical: attribute 'swapped' produces classical inversions
  7303 of introduction rules;
  7304 
  7305 * Provers/simplifier: 'simplified' attribute may refer to explicit
  7306 rules instead of full simplifier context; 'iff' attribute handles
  7307 conditional rules;
  7308 
  7309 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  7310 
  7311 * HOL: 'recdef' now fails on unfinished automated proofs, use
  7312 "(permissive)" option to recover old behavior;
  7313 
  7314 * HOL: 'inductive' no longer features separate (collective) attributes
  7315 for 'intros' (was found too confusing);
  7316 
  7317 * HOL: properly declared induction rules less_induct and
  7318 wf_induct_rule;
  7319 
  7320 
  7321 *** HOL ***
  7322 
  7323 * HOL: moved over to sane numeral syntax; the new policy is as
  7324 follows:
  7325 
  7326   - 0 and 1 are polymorphic constants, which are defined on any
  7327   numeric type (nat, int, real etc.);
  7328 
  7329   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  7330   binary representation internally;
  7331 
  7332   - type nat has special constructor Suc, and generally prefers Suc 0
  7333   over 1::nat and Suc (Suc 0) over 2::nat;
  7334 
  7335 This change may cause significant problems of INCOMPATIBILITY; here
  7336 are some hints on converting existing sources:
  7337 
  7338   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  7339   entities, so expressions involving "-" (unary or binary minus) need
  7340   to be spaced properly;
  7341 
  7342   - existing occurrences of "1" may need to be constraint "1::nat" or
  7343   even replaced by Suc 0; similar for old "2";
  7344 
  7345   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  7346 
  7347   - remove all special provisions on numerals in proofs;
  7348 
  7349 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  7350 representation (depends on bin_arith_simps in the default context);
  7351 
  7352 * HOL: symbolic syntax for x^2 (numeral 2);
  7353 
  7354 * HOL: the class of all HOL types is now called "type" rather than
  7355 "term"; INCOMPATIBILITY, need to adapt references to this type class
  7356 in axclass/classes, instance/arities, and (usually rare) occurrences
  7357 in typings (of consts etc.); internally the class is called
  7358 "HOL.type", ML programs should refer to HOLogic.typeS;
  7359 
  7360 * HOL/record package improvements:
  7361   - new derived operations "fields" to build a partial record section,
  7362     "extend" to promote a fixed record to a record scheme, and
  7363     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  7364     declared as simp by default;
  7365   - shared operations ("more", "fields", etc.) now need to be always
  7366     qualified) --- potential INCOMPATIBILITY;
  7367   - removed "make_scheme" operations (use "make" with "extend") --
  7368     INCOMPATIBILITY;
  7369   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  7370   - provides cases/induct rules for use with corresponding Isar
  7371     methods (for concrete records, record schemes, concrete more
  7372     parts, and schematic more parts -- in that order);
  7373   - internal definitions directly based on a light-weight abstract
  7374     theory of product types over typedef rather than datatype;
  7375 
  7376 * HOL: generic code generator for generating executable ML code from
  7377 specifications; specific support for HOL constructs such as inductive
  7378 datatypes and sets, as well as recursive functions; can be invoked
  7379 via 'generate_code' theory section;
  7380 
  7381 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  7382 
  7383 * HOL: consolidated and renamed several theories.  In particular:
  7384         Ord.thy has been absorbed into HOL.thy
  7385         String.thy has been absorbed into List.thy
  7386 
  7387 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  7388 (beware of argument permutation!);
  7389 
  7390 * HOL: linorder_less_split superseded by linorder_cases;
  7391 
  7392 * HOL/List: "nodups" renamed to "distinct";
  7393 
  7394 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  7395 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  7396   - Ex_def has changed, now need to use some_eq_ex
  7397 
  7398 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  7399 in this (rare) case use:
  7400 
  7401   delSWrapper "split_all_tac"
  7402   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  7403 
  7404 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  7405 MAY FAIL;
  7406 
  7407 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  7408 Isabelle's type classes, ^ on functions and relations has too general
  7409 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  7410 necessary to attach explicit type constraints;
  7411 
  7412 * HOL/Relation: the prefix name of the infix "O" has been changed from
  7413 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  7414 renamed accordingly (eg "compI" -> "rel_compI").
  7415 
  7416 * HOL: syntax translations now work properly with numerals and records
  7417 expressions;
  7418 
  7419 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  7420 of "lam" -- INCOMPATIBILITY;
  7421 
  7422 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  7423 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  7424 renamed "Product_Type.unit";
  7425 
  7426 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  7427 
  7428 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  7429 the "cases" method);
  7430 
  7431 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  7432 Florian Kammller);
  7433 
  7434 * HOL/IMP: updated and converted to new-style theory format; several
  7435 parts turned into readable document, with proper Isar proof texts and
  7436 some explanations (by Gerwin Klein);
  7437 
  7438 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  7439 
  7440 * HOL-Hyperreal is now a logic image;
  7441 
  7442 
  7443 *** HOLCF ***
  7444 
  7445 * Isar: consts/constdefs supports mixfix syntax for continuous
  7446 operations;
  7447 
  7448 * Isar: domain package adapted to new-style theory format, e.g. see
  7449 HOLCF/ex/Dnat.thy;
  7450 
  7451 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7452 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7453 lift.induct_tac, always use UU instead of Undef;
  7454 
  7455 * HOLCF/IMP: updated and converted to new-style theory;
  7456 
  7457 
  7458 *** ZF ***
  7459 
  7460 * Isar: proper integration of logic-specific tools and packages,
  7461 including theory commands '(co)inductive', '(co)datatype',
  7462 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7463 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7464 
  7465 * theory Main no longer includes AC; for the Axiom of Choice, base
  7466 your theory on Main_ZFC;
  7467 
  7468 * the integer library now covers quotients and remainders, with many
  7469 laws relating division to addition, multiplication, etc.;
  7470 
  7471 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7472 typeless version of the formalism;
  7473 
  7474 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7475 format;
  7476 
  7477 * ZF/Induct: new directory for examples of inductive definitions,
  7478 including theory Multiset for multiset orderings; converted to
  7479 new-style theory format;
  7480 
  7481 * ZF: many new theorems about lists, ordinals, etc.;
  7482 
  7483 
  7484 *** General ***
  7485 
  7486 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7487 variable proof controls level of detail: 0 = no proofs (only oracle
  7488 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7489 also ref manual for further ML interfaces;
  7490 
  7491 * Pure/axclass: removed obsolete ML interface
  7492 goal_subclass/goal_arity;
  7493 
  7494 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7495 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7496 separate tokens, so expressions involving minus need to be spaced
  7497 properly;
  7498 
  7499 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7500 rather than "infixl" or "infixr";
  7501 
  7502 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7503 sort constraint specifications in type inference; e.g. "x::_::foo"
  7504 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7505 type variable);
  7506 
  7507 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7508 control output of nested => (types); the default behavior is
  7509 "type_brackets";
  7510 
  7511 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7512 tokens into AST constants;
  7513 
  7514 * Pure/syntax: prefer later declarations of translations and print
  7515 translation functions; potential INCOMPATIBILITY: need to reverse
  7516 multiple declarations for same syntax element constant;
  7517 
  7518 * Pure/show_hyps reset by default (in accordance to existing Isar
  7519 practice);
  7520 
  7521 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7522 addSafter;
  7523 
  7524 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7525 as well;
  7526 
  7527 * system: tested support for MacOS X; should be able to get Isabelle +
  7528 Proof General to work in a plain Terminal after installing Poly/ML
  7529 (e.g. from the Isabelle distribution area) and GNU bash alone
  7530 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7531 support requires further installations, e.g. from
  7532 http://fink.sourceforge.net/);
  7533 
  7534 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7535 
  7536 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7537 of 40 MB), cf. ML_OPTIONS;
  7538 
  7539 * system: Proof General keywords specification is now part of the
  7540 Isabelle distribution (see etc/isar-keywords.el);
  7541 
  7542 * system: support for persistent Proof General sessions (refrain from
  7543 outdating all loaded theories on startup); user may create writable
  7544 logic images like this: ``isabelle -q HOL Test'';
  7545 
  7546 * system: smart selection of Isabelle process versus Isabelle
  7547 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7548 run both "isabelle" and "Isabelle" even if file names are badly
  7549 damaged (executable inspects the case of the first letter of its own
  7550 name); added separate "isabelle-process" and "isabelle-interface";
  7551 
  7552 * system: refrain from any attempt at filtering input streams; no
  7553 longer support ``8bit'' encoding of old isabelle font, instead proper
  7554 iso-latin characters may now be used; the related isatools
  7555 "symbolinput" and "nonascii" have disappeared as well;
  7556 
  7557 * system: removed old "xterm" interface (the print modes "xterm" and
  7558 "xterm_color" are still available for direct use in a suitable
  7559 terminal);
  7560 
  7561 
  7562 
  7563 New in Isabelle99-2 (February 2001)
  7564 -----------------------------------
  7565 
  7566 *** Overview of INCOMPATIBILITIES ***
  7567 
  7568 * HOL: please note that theories in the Library and elsewhere often use the
  7569 new-style (Isar) format; to refer to their theorems in an ML script you must
  7570 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  7571 
  7572 * HOL: inductive package no longer splits induction rule aggressively,
  7573 but only as far as specified by the introductions given; the old
  7574 format may be recovered via ML function complete_split_rule or attribute
  7575 'split_rule (complete)';
  7576 
  7577 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  7578 gfp_Tarski to gfp_unfold;
  7579 
  7580 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  7581 
  7582 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  7583 relation); infix "^^" has been renamed "``"; infix "``" has been
  7584 renamed "`"; "univalent" has been renamed "single_valued";
  7585 
  7586 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  7587 operation;
  7588 
  7589 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  7590 
  7591 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  7592 
  7593 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  7594 consequence, it is no longer monotonic wrt. the local goal context
  7595 (which is now passed through the inductive cases);
  7596 
  7597 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  7598 \<gg> to \<ggreater>;
  7599 
  7600 
  7601 *** Document preparation ***
  7602 
  7603 * \isabellestyle{NAME} selects version of Isabelle output (currently
  7604 available: are "it" for near math-mode best-style output, "sl" for
  7605 slanted text style, and "tt" for plain type-writer; if no
  7606 \isabellestyle command is given, output is according to slanted
  7607 type-writer);
  7608 
  7609 * support sub/super scripts (for single symbols only), input syntax is
  7610 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  7611 
  7612 * some more standard symbols; see Appendix A of the system manual for
  7613 the complete list of symbols defined in isabellesym.sty;
  7614 
  7615 * improved isabelle style files; more abstract symbol implementation
  7616 (should now use \isamath{...} and \isatext{...} in custom symbol
  7617 definitions);
  7618 
  7619 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  7620 state; Note that presentation of goal states does not conform to
  7621 actual human-readable proof documents.  Please do not include goal
  7622 states into document output unless you really know what you are doing!
  7623 
  7624 * proper indentation of antiquoted output with proportional LaTeX
  7625 fonts;
  7626 
  7627 * no_document ML operator temporarily disables LaTeX document
  7628 generation;
  7629 
  7630 * isatool unsymbolize tunes sources for plain ASCII communication;
  7631 
  7632 
  7633 *** Isar ***
  7634 
  7635 * Pure: Isar now suffers initial goal statements to contain unbound
  7636 schematic variables (this does not conform to actual readable proof
  7637 documents, due to unpredictable outcome and non-compositional proof
  7638 checking); users who know what they are doing may use schematic goals
  7639 for Prolog-style synthesis of proven results;
  7640 
  7641 * Pure: assumption method (an implicit finishing) now handles actual
  7642 rules as well;
  7643 
  7644 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  7645 initial goal, declare "that" only as Pure intro (only for single
  7646 steps); the "that" rule assumption may now be involved in implicit
  7647 finishing, thus ".." becomes a feasible for trivial obtains;
  7648 
  7649 * Pure: default proof step now includes 'intro_classes'; thus trivial
  7650 instance proofs may be performed by "..";
  7651 
  7652 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  7653 statements as well;
  7654 
  7655 * Pure: more robust selection of calculational rules;
  7656 
  7657 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  7658 rule (as well as the assumption rule);
  7659 
  7660 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  7661 lemmas, using the graph browser tool;
  7662 
  7663 * Pure: predict failure of "show" in interactive mode;
  7664 
  7665 * Pure: 'thms_containing' now takes actual terms as arguments;
  7666 
  7667 * HOL: improved method 'induct' --- now handles non-atomic goals
  7668 (potential INCOMPATIBILITY); tuned error handling;
  7669 
  7670 * HOL: cases and induct rules now provide explicit hints about the
  7671 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  7672 any remaining facts are inserted into the goal verbatim;
  7673 
  7674 * HOL: local contexts (aka cases) may now contain term bindings as
  7675 well; the 'cases' and 'induct' methods new provide a ?case binding for
  7676 the result to be shown in each case;
  7677 
  7678 * HOL: added 'recdef_tc' command;
  7679 
  7680 * isatool convert assists in eliminating legacy ML scripts;
  7681 
  7682 
  7683 *** HOL ***
  7684 
  7685 * HOL/Library: a collection of generic theories to be used together
  7686 with main HOL; the theory loader path already includes this directory
  7687 by default; the following existing theories have been moved here:
  7688 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  7689 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  7690 
  7691 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  7692 modelling and verification task performed in Isabelle/HOL +
  7693 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  7694 
  7695 * HOL/Algebra: special summation operator SUM no longer exists, it has
  7696 been replaced by setsum; infix 'assoc' now has priority 50 (like
  7697 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  7698 'domain', this makes the theory consistent with mathematical
  7699 literature;
  7700 
  7701 * HOL basics: added overloaded operations "inverse" and "divide"
  7702 (infix "/"), syntax for generic "abs" operation, generic summation
  7703 operator \<Sum>;
  7704 
  7705 * HOL/typedef: simplified package, provide more useful rules (see also
  7706 HOL/subset.thy);
  7707 
  7708 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  7709 now expressed as a proper nested rule (old-style tactic scripts may
  7710 require atomize_strip_tac to cope with non-atomic premises);
  7711 
  7712 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  7713 to "split_conv" (old name still available for compatibility);
  7714 
  7715 * HOL: improved concrete syntax for strings (e.g. allows translation
  7716 rules with string literals);
  7717 
  7718 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  7719  and Fleuriot's mechanization of analysis, including the transcendental
  7720  functions for the reals;
  7721 
  7722 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  7723 
  7724 
  7725 *** CTT ***
  7726 
  7727 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  7728 "lam" is displayed as TWO lambda-symbols
  7729 
  7730 * CTT: theory Main now available, containing everything (that is, Bool
  7731 and Arith);
  7732 
  7733 
  7734 *** General ***
  7735 
  7736 * Pure: the Simplifier has been implemented properly as a derived rule
  7737 outside of the actual kernel (at last!); the overall performance
  7738 penalty in practical applications is about 50%, while reliability of
  7739 the Isabelle inference kernel has been greatly improved;
  7740 
  7741 * print modes "brackets" and "no_brackets" control output of nested =>
  7742 (types) and ==> (props); the default behaviour is "brackets";
  7743 
  7744 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7745 as assumptions as well;
  7746 
  7747 * system: support Poly/ML 4.0;
  7748 
  7749 * system: isatool install handles KDE version 1 or 2;
  7750 
  7751 
  7752 
  7753 New in Isabelle99-1 (October 2000)
  7754 ----------------------------------
  7755 
  7756 *** Overview of INCOMPATIBILITIES ***
  7757 
  7758 * HOL: simplification of natural numbers is much changed; to partly
  7759 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7760 issue the following ML commands:
  7761 
  7762   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7763   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7764 
  7765 * HOL: simplification no longer dives into case-expressions; this is
  7766 controlled by "t.weak_case_cong" for each datatype t;
  7767 
  7768 * HOL: nat_less_induct renamed to less_induct;
  7769 
  7770 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7771 fixsome to patch .thy and .ML sources automatically;
  7772 
  7773   select_equality  -> some_equality
  7774   select_eq_Ex     -> some_eq_ex
  7775   selectI2EX       -> someI2_ex
  7776   selectI2         -> someI2
  7777   selectI          -> someI
  7778   select1_equality -> some1_equality
  7779   Eps_sym_eq       -> some_sym_eq_trivial
  7780   Eps_eq           -> some_eq_trivial
  7781 
  7782 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7783 
  7784 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7785 instead);
  7786 
  7787 * HOL: the recursion equations generated by 'recdef' are now called
  7788 f.simps instead of f.rules;
  7789 
  7790 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7791 
  7792 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7793 sometimes be needed;
  7794 
  7795 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7796 
  7797 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7798 
  7799 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7800 product is now "<*>" instead of "Times"; the lexicographic product is
  7801 now "<*lex*>" instead of "**";
  7802 
  7803 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7804 of main HOL, but was unused); better use HOL's datatype package;
  7805 
  7806 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7807 the old syntax may be recovered as follows:
  7808 
  7809   syntax (symbols)
  7810     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7811       (infixl "\\<oplus>" 100)
  7812 
  7813 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7814 
  7815 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7816 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7817 internally;
  7818 
  7819 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7820 changed from A/r to A//r;
  7821 
  7822 * ZF: new treatment of arithmetic (nat & int) may break some old
  7823 proofs;
  7824 
  7825 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7826 rulify -> rule_format, elimify -> elim_format, ...);
  7827 
  7828 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7829 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7830 should have to change intro!! to intro? only); replaced "delrule" by
  7831 "rule del";
  7832 
  7833 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7834 
  7835 * Provers: strengthened force_tac by using new first_best_tac;
  7836 
  7837 * LaTeX document preparation: several changes of isabelle.sty (see
  7838 lib/texinputs);
  7839 
  7840 
  7841 *** Document preparation ***
  7842 
  7843 * formal comments (text blocks etc.) in new-style theories may now
  7844 contain antiquotations of thm/prop/term/typ/text to be presented
  7845 according to latex print mode; concrete syntax is like this:
  7846 @{term[show_types] "f(x) = a + x"};
  7847 
  7848 * isatool mkdir provides easy setup of Isabelle session directories,
  7849 including proper document sources;
  7850 
  7851 * generated LaTeX sources are now deleted after successful run
  7852 (isatool document -c); may retain a copy somewhere else via -D option
  7853 of isatool usedir;
  7854 
  7855 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7856 style files, achieving self-contained LaTeX sources and simplifying
  7857 LaTeX debugging;
  7858 
  7859 * old-style theories now produce (crude) LaTeX output as well;
  7860 
  7861 * browser info session directories are now self-contained (may be put
  7862 on WWW server seperately); improved graphs of nested sessions; removed
  7863 graph for 'all sessions';
  7864 
  7865 * several improvements in isabelle style files; \isabellestyle{it}
  7866 produces fake math mode output; \isamarkupheader is now \section by
  7867 default; see lib/texinputs/isabelle.sty etc.;
  7868 
  7869 
  7870 *** Isar ***
  7871 
  7872 * Isar/Pure: local results and corresponding term bindings are now
  7873 subject to Hindley-Milner polymorphism (similar to ML); this
  7874 accommodates incremental type-inference very nicely;
  7875 
  7876 * Isar/Pure: new derived language element 'obtain' supports
  7877 generalized existence reasoning;
  7878 
  7879 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7880 support accumulation of results, without applying any rules yet;
  7881 useful to collect intermediate results without explicit name
  7882 references, and for use with transitivity rules with more than 2
  7883 premises;
  7884 
  7885 * Isar/Pure: scalable support for case-analysis type proofs: new
  7886 'case' language element refers to local contexts symbolically, as
  7887 produced by certain proof methods; internally, case names are attached
  7888 to theorems as "tags";
  7889 
  7890 * Isar/Pure: theory command 'hide' removes declarations from
  7891 class/type/const name spaces;
  7892 
  7893 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7894 indicate potential overloading;
  7895 
  7896 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7897 
  7898 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7899 "{a,b,c}" instead of {a,b,c};
  7900 
  7901 * Isar/Pure now provides its own version of intro/elim/dest
  7902 attributes; useful for building new logics, but beware of confusion
  7903 with the version in Provers/classical;
  7904 
  7905 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7906 case name 'antecedent';
  7907 
  7908 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7909 to the current context is now done automatically);
  7910 
  7911 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7912 for definining proof methods in ML;
  7913 
  7914 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7915 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7916 most cases, one should have to change intro!! to intro? only);
  7917 replaced "delrule" by "rule del";
  7918 
  7919 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7920 'symmetric' attribute (the latter supercedes [RS sym]);
  7921 
  7922 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7923 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7924 well (including splits);
  7925 
  7926 * Isar/Provers: Simplifier and Classical methods now support all kind
  7927 of modifiers used in the past, including 'cong', 'iff', etc.
  7928 
  7929 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7930 of Simplifier and Classical reasoner);
  7931 
  7932 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7933 now support named cases; major packages (inductive, datatype, primrec,
  7934 recdef) support case names and properly name parameters;
  7935 
  7936 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7937 monotonicity conditions are extracted to be proven at end of
  7938 calculations;
  7939 
  7940 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7941 method anyway;
  7942 
  7943 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7944 split_if split_if_asm; datatype package provides theorems foo.splits =
  7945 foo.split foo.split_asm for each datatype;
  7946 
  7947 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7948 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7949 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  7950 use "(cases (simplified))" method in proper proof texts);
  7951 
  7952 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  7953 
  7954 * Isar: names of theorems etc. may be natural numbers as well;
  7955 
  7956 * Isar: 'pr' command: optional arguments for goals_limit and
  7957 ProofContext.prems_limit; no longer prints theory contexts, but only
  7958 proof states;
  7959 
  7960 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  7961 additional print modes to be specified; e.g. "pr(latex)" will print
  7962 proof state according to the Isabelle LaTeX style;
  7963 
  7964 * Isar: improved support for emulating tactic scripts, including proof
  7965 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  7966 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  7967 (for HOL datatypes);
  7968 
  7969 * Isar: simplified (more robust) goal selection of proof methods: 1st
  7970 goal, all goals, or explicit goal specifier (tactic emulation); thus
  7971 'proof method scripts' have to be in depth-first order;
  7972 
  7973 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  7974 
  7975 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  7976 should instead use individual commands for printing items
  7977 (print_commands, print_methods etc.);
  7978 
  7979 * Isar: added 'nothing' --- the empty list of theorems;
  7980 
  7981 
  7982 *** HOL ***
  7983 
  7984 * HOL/MicroJava: formalization of a fragment of Java, together with a
  7985 corresponding virtual machine and a specification of its bytecode
  7986 verifier and a lightweight bytecode verifier, including proofs of
  7987 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  7988 Cornelia Pusch (see also the homepage of project Bali at
  7989 http://isabelle.in.tum.de/Bali/);
  7990 
  7991 * HOL/Algebra: new theory of rings and univariate polynomials, by
  7992 Clemens Ballarin;
  7993 
  7994 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  7995 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  7996 Rasmussen;
  7997 
  7998 * HOL/Lattice: fundamental concepts of lattice theory and order
  7999 structures, including duals, properties of bounds versus algebraic
  8000 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  8001 Theorem for complete lattices etc.; may also serve as a demonstration
  8002 for abstract algebraic reasoning using axiomatic type classes, and
  8003 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  8004 
  8005 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  8006 von Oheimb;
  8007 
  8008 * HOL/IMPP: extension of IMP with local variables and mutually
  8009 recursive procedures, by David von Oheimb;
  8010 
  8011 * HOL/Lambda: converted into new-style theory and document;
  8012 
  8013 * HOL/ex/Multiquote: example of multiple nested quotations and
  8014 anti-quotations -- basically a generalized version of de-Bruijn
  8015 representation; very useful in avoiding lifting of operations;
  8016 
  8017 * HOL/record: added general record equality rule to simpset; fixed
  8018 select-update simplification procedure to handle extended records as
  8019 well; admit "r" as field name;
  8020 
  8021 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  8022 other numeric types and also as the identity of groups, rings, etc.;
  8023 
  8024 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  8025 Types nat and int belong to this axclass;
  8026 
  8027 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  8028    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  8029    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  8030   two terms #m*u and #n*u are replaced by #(m+n)*u
  8031     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  8032   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  8033     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  8034 
  8035 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  8036 powerful prover for predicate logic but knows nothing of clasets; see
  8037 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  8038 
  8039 * HOL: new version of "case_tac" subsumes both boolean case split and
  8040 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  8041 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  8042 
  8043 * HOL: simplification no longer dives into case-expressions: only the
  8044 selector expression is simplified, but not the remaining arms; to
  8045 enable full simplification of case-expressions for datatype t, you may
  8046 remove t.weak_case_cong from the simpset, either globally (Delcongs
  8047 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  8048 
  8049 * HOL/recdef: the recursion equations generated by 'recdef' for
  8050 function 'f' are now called f.simps instead of f.rules; if all
  8051 termination conditions are proved automatically, these simplification
  8052 rules are added to the simpset, as in primrec; rules may be named
  8053 individually as well, resulting in a separate list of theorems for
  8054 each equation;
  8055 
  8056 * HOL/While is a new theory that provides a while-combinator. It
  8057 permits the definition of tail-recursive functions without the
  8058 provision of a termination measure. The latter is necessary once the
  8059 invariant proof rule for while is applied.
  8060 
  8061 * HOL: new (overloaded) notation for the set of elements below/above
  8062 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  8063 
  8064 * HOL: theorems impI, allI, ballI bound as "strip";
  8065 
  8066 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  8067 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  8068 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  8069 
  8070 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  8071 
  8072 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  8073 main HOL, but was unused);
  8074 
  8075 * HOL: fewer consts declared as global (e.g. have to refer to
  8076 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  8077 
  8078 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  8079 in case of overlap with user translations (e.g. judgements over
  8080 tuples); (note that the underlying logical represenation is still
  8081 bogus);
  8082 
  8083 
  8084 *** ZF ***
  8085 
  8086 * ZF: simplification automatically cancels common terms in arithmetic
  8087 expressions over nat and int;
  8088 
  8089 * ZF: new treatment of nat to minimize type-checking: all operators
  8090 coerce their operands to a natural number using the function natify,
  8091 making the algebraic laws unconditional;
  8092 
  8093 * ZF: as above, for int: operators coerce their operands to an integer
  8094 using the function intify;
  8095 
  8096 * ZF: the integer library now contains many of the usual laws for the
  8097 orderings, including $<=, and monotonicity laws for $+ and $*;
  8098 
  8099 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  8100 simplification;
  8101 
  8102 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  8103 to the simplifier and classical reasoner simultaneously;
  8104 
  8105 
  8106 *** General ***
  8107 
  8108 * Provers: blast_tac now handles actual object-logic rules as
  8109 assumptions; note that auto_tac uses blast_tac internally as well;
  8110 
  8111 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  8112 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  8113 
  8114 * Provers: delrules now handles destruct rules as well (no longer need
  8115 explicit make_elim);
  8116 
  8117 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  8118   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8119 use instead the strong form,
  8120   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8121 in HOL, FOL and ZF the function cla_make_elim will create such rules
  8122 from destruct-rules;
  8123 
  8124 * Provers: Simplifier.easy_setup provides a fast path to basic
  8125 Simplifier setup for new object-logics;
  8126 
  8127 * Pure: AST translation rules no longer require constant head on LHS;
  8128 
  8129 * Pure: improved name spaces: ambiguous output is qualified; support
  8130 for hiding of names;
  8131 
  8132 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  8133 XSYMBOL_HOME; no longer need to do manual configuration in most
  8134 situations;
  8135 
  8136 * system: compression of ML heaps images may now be controlled via -c
  8137 option of isabelle and isatool usedir (currently only observed by
  8138 Poly/ML);
  8139 
  8140 * system: isatool installfonts may handle X-Symbol fonts as well (very
  8141 useful for remote X11);
  8142 
  8143 * system: provide TAGS file for Isabelle sources;
  8144 
  8145 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  8146 order;
  8147 
  8148 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  8149 timing flag supersedes proof_timing and Toplevel.trace;
  8150 
  8151 * ML: new combinators |>> and |>>> for incremental transformations
  8152 with secondary results (e.g. certain theory extensions):
  8153 
  8154 * ML: PureThy.add_defs gets additional argument to indicate potential
  8155 overloading (usually false);
  8156 
  8157 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  8158 results;
  8159 
  8160 
  8161 
  8162 New in Isabelle99 (October 1999)
  8163 --------------------------------
  8164 
  8165 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8166 
  8167 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  8168 are no longer simplified.  (This allows the simplifier to unfold recursive
  8169 functional programs.)  To restore the old behaviour, declare
  8170 
  8171     Delcongs [if_weak_cong];
  8172 
  8173 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  8174 complement;
  8175 
  8176 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  8177 
  8178 * HOL/datatype: mutual_induct_tac no longer exists --
  8179   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  8180 
  8181 * HOL/typedef: fixed type inference for representing set; type
  8182 arguments now have to occur explicitly on the rhs as type constraints;
  8183 
  8184 * ZF: The con_defs part of an inductive definition may no longer refer
  8185 to constants declared in the same theory;
  8186 
  8187 * HOL, ZF: the function mk_cases, generated by the inductive
  8188 definition package, has lost an argument.  To simplify its result, it
  8189 uses the default simpset instead of a supplied list of theorems.
  8190 
  8191 * HOL/List: the constructors of type list are now Nil and Cons;
  8192 
  8193 * Simplifier: the type of the infix ML functions
  8194         setSSolver addSSolver setSolver addSolver
  8195 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  8196 for packaging solvers. A solver is created via
  8197         mk_solver: string -> (thm list -> int -> tactic) -> solver
  8198 where the string argument is only a comment.
  8199 
  8200 
  8201 *** Proof tools ***
  8202 
  8203 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  8204 decision procedure for linear arithmetic. Currently it is used for
  8205 types `nat', `int', and `real' in HOL (see below); it can, should and
  8206 will be instantiated for other types and logics as well.
  8207 
  8208 * The simplifier now accepts rewrite rules with flexible heads, eg
  8209      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  8210   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  8211   matching.
  8212 
  8213 
  8214 *** General ***
  8215 
  8216 * New Isabelle/Isar subsystem provides an alternative to traditional
  8217 tactical theorem proving; together with the ProofGeneral/isar user
  8218 interface it offers an interactive environment for developing human
  8219 readable proof documents (Isar == Intelligible semi-automated
  8220 reasoning); for further information see isatool doc isar-ref,
  8221 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  8222 
  8223 * improved and simplified presentation of theories: better HTML markup
  8224 (including colors), graph views in several sizes; isatool usedir now
  8225 provides a proper interface for user theories (via -P option); actual
  8226 document preparation based on (PDF)LaTeX is available as well (for
  8227 new-style theories only); see isatool doc system for more information;
  8228 
  8229 * native support for Proof General, both for classic Isabelle and
  8230 Isabelle/Isar;
  8231 
  8232 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  8233 using the graph browser tool;
  8234 
  8235 * Isabelle manuals now also available as PDF;
  8236 
  8237 * theory loader rewritten from scratch (may not be fully
  8238 bug-compatible); old loadpath variable has been replaced by show_path,
  8239 add_path, del_path, reset_path functions; new operations such as
  8240 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  8241 isatool doc ref);
  8242 
  8243 * improved isatool install: option -k creates KDE application icon,
  8244 option -p DIR installs standalone binaries;
  8245 
  8246 * added ML_PLATFORM setting (useful for cross-platform installations);
  8247 more robust handling of platform specific ML images for SML/NJ;
  8248 
  8249 * the settings environment is now statically scoped, i.e. it is never
  8250 created again in sub-processes invoked from isabelle, isatool, or
  8251 Isabelle;
  8252 
  8253 * path element specification '~~' refers to '$ISABELLE_HOME';
  8254 
  8255 * in locales, the "assumes" and "defines" parts may be omitted if
  8256 empty;
  8257 
  8258 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  8259 long arrows);
  8260 
  8261 * new print_mode "HTML";
  8262 
  8263 * new flag show_tags controls display of tags of theorems (which are
  8264 basically just comments that may be attached by some tools);
  8265 
  8266 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  8267 mode and goal output format:
  8268 
  8269 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  8270 244c244
  8271 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  8272 ---
  8273 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  8274 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  8275 181c181
  8276 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  8277 ---
  8278 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  8279 
  8280 * function bind_thms stores lists of theorems (cf. bind_thm);
  8281 
  8282 * new shorthand tactics ftac, eatac, datac, fatac;
  8283 
  8284 * qed (and friends) now accept "" as result name; in that case the
  8285 theorem is not stored, but proper checks and presentation of the
  8286 result still apply;
  8287 
  8288 * theorem database now also indexes constants "Trueprop", "all",
  8289 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  8290 
  8291 
  8292 *** HOL ***
  8293 
  8294 ** HOL arithmetic **
  8295 
  8296 * There are now decision procedures for linear arithmetic over nat and
  8297 int:
  8298 
  8299 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  8300 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  8301 are treated as atomic; subformulae not involving type `nat' or `int'
  8302 are ignored; quantified subformulae are ignored unless they are
  8303 positive universal or negative existential. The tactic has to be
  8304 invoked by hand and can be a little bit slow. In particular, the
  8305 running time is exponential in the number of occurrences of `min' and
  8306 `max', and `-' on `nat'.
  8307 
  8308 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  8309 (negated) (in)equalities among the premises and the conclusion into
  8310 account (i.e. no compound formulae) and does not know about `min' and
  8311 `max', and `-' on `nat'. It is fast and is used automatically by the
  8312 simplifier.
  8313 
  8314 NB: At the moment, these decision procedures do not cope with mixed
  8315 nat/int formulae where the two parts interact, such as `m < n ==>
  8316 int(m) < int(n)'.
  8317 
  8318 * HOL/Numeral provides a generic theory of numerals (encoded
  8319 efficiently as bit strings); setup for types nat/int/real is in place;
  8320 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  8321 int, existing theories and proof scripts may require a few additional
  8322 type constraints;
  8323 
  8324 * integer division and remainder can now be performed on constant
  8325 arguments;
  8326 
  8327 * many properties of integer multiplication, division and remainder
  8328 are now available;
  8329 
  8330 * An interface to the Stanford Validity Checker (SVC) is available through the
  8331 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  8332 are proved automatically.  SVC must be installed separately, and its results
  8333 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  8334 invocation of the underlying oracle).  For SVC see
  8335   http://verify.stanford.edu/SVC
  8336 
  8337 * IsaMakefile: the HOL-Real target now builds an actual image;
  8338 
  8339 
  8340 ** HOL misc **
  8341 
  8342 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  8343 (in Isabelle/Isar) -- by Gertrud Bauer;
  8344 
  8345 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  8346 analysis for assembly languages with subtypes;
  8347 
  8348 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  8349 -- avoids syntactic ambiguities and treats state, transition, and
  8350 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  8351 changed syntax and (many) tactics;
  8352 
  8353 * HOL/inductive: Now also handles more general introduction rules such
  8354   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  8355   theorems are now maintained within the theory (maintained via the
  8356   "mono" attribute);
  8357 
  8358 * HOL/datatype: Now also handles arbitrarily branching datatypes
  8359   (using function types) such as
  8360 
  8361   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  8362 
  8363 * HOL/record: record_simproc (part of the default simpset) takes care
  8364 of selectors applied to updated records; record_split_tac is no longer
  8365 part of the default claset; update_defs may now be removed from the
  8366 simpset in many cases; COMPATIBILITY: old behavior achieved by
  8367 
  8368   claset_ref () := claset() addSWrapper record_split_wrapper;
  8369   Delsimprocs [record_simproc]
  8370 
  8371 * HOL/typedef: fixed type inference for representing set; type
  8372 arguments now have to occur explicitly on the rhs as type constraints;
  8373 
  8374 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  8375 names rather than an ML expression;
  8376 
  8377 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  8378 supplied later.  Program schemes can be defined, such as
  8379     "While B C s = (if B s then While B C (C s) else s)"
  8380 where the well-founded relation can be chosen after B and C have been given.
  8381 
  8382 * HOL/List: the constructors of type list are now Nil and Cons;
  8383 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  8384 course, ML tools referring to List.list.op # etc. have to be adapted;
  8385 
  8386 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  8387 disabled by default; run isabelle with option -m HOL to get back to
  8388 the original Gordon/HOL-style output;
  8389 
  8390 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  8391 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  8392 
  8393 * HOL basic syntax simplified (more orthogonal): all variants of
  8394 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  8395 Eps operator is provided as well: "SOME x. P[x]";
  8396 
  8397 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  8398 
  8399 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  8400 thus available for user theories;
  8401 
  8402 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  8403 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  8404 time;
  8405 
  8406 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  8407 several times and then mp;
  8408 
  8409 
  8410 *** LK ***
  8411 
  8412 * the notation <<...>> is now available as a notation for sequences of
  8413 formulas;
  8414 
  8415 * the simplifier is now installed
  8416 
  8417 * the axiom system has been generalized (thanks to Soren Heilmann)
  8418 
  8419 * the classical reasoner now has a default rule database
  8420 
  8421 
  8422 *** ZF ***
  8423 
  8424 * new primrec section allows primitive recursive functions to be given
  8425 directly (as in HOL) over datatypes and the natural numbers;
  8426 
  8427 * new tactics induct_tac and exhaust_tac for induction (or case
  8428 analysis) over datatypes and the natural numbers;
  8429 
  8430 * the datatype declaration of type T now defines the recursor T_rec;
  8431 
  8432 * simplification automatically does freeness reasoning for datatype
  8433 constructors;
  8434 
  8435 * automatic type-inference, with AddTCs command to insert new
  8436 type-checking rules;
  8437 
  8438 * datatype introduction rules are now added as Safe Introduction rules
  8439 to the claset;
  8440 
  8441 * the syntax "if P then x else y" is now available in addition to
  8442 if(P,x,y);
  8443 
  8444 
  8445 *** Internal programming interfaces ***
  8446 
  8447 * tuned simplifier trace output; new flag debug_simp;
  8448 
  8449 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8450 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8451 
  8452 * AxClass.axclass_tac lost the theory argument;
  8453 
  8454 * tuned current_goals_markers semantics: begin / end goal avoids
  8455 printing empty lines;
  8456 
  8457 * removed prs and prs_fn hook, which was broken because it did not
  8458 include \n in its semantics, forcing writeln to add one
  8459 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8460 string -> unit if you really want to output text without newline;
  8461 
  8462 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8463 plain output, interface builders may have to enable 'isabelle_font'
  8464 mode to get Isabelle font glyphs as before;
  8465 
  8466 * refined token_translation interface; INCOMPATIBILITY: output length
  8467 now of type real instead of int;
  8468 
  8469 * theory loader actions may be traced via new ThyInfo.add_hook
  8470 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8471 your own database of information attached to *whole* theories -- as
  8472 opposed to intra-theory data slots offered via TheoryDataFun;
  8473 
  8474 * proper handling of dangling sort hypotheses (at last!);
  8475 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8476 extra sort hypotheses that can be witnessed from the type signature;
  8477 the force_strip_shyps flag is gone, any remaining shyps are simply
  8478 left in the theorem (with a warning issued by strip_shyps_warning);
  8479 
  8480 
  8481 
  8482 New in Isabelle98-1 (October 1998)
  8483 ----------------------------------
  8484 
  8485 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8486 
  8487 * several changes of automated proof tools;
  8488 
  8489 * HOL: major changes to the inductive and datatype packages, including
  8490 some minor incompatibilities of theory syntax;
  8491 
  8492 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8493 called `inj_on';
  8494 
  8495 * HOL: removed duplicate thms in Arith:
  8496   less_imp_add_less  should be replaced by  trans_less_add1
  8497   le_imp_add_le      should be replaced by  trans_le_add1
  8498 
  8499 * HOL: unary minus is now overloaded (new type constraints may be
  8500 required);
  8501 
  8502 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8503 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8504 now taken as an integer constant.
  8505 
  8506 * Pure: ML function 'theory_of' renamed to 'theory';
  8507 
  8508 
  8509 *** Proof tools ***
  8510 
  8511 * Simplifier:
  8512   1. Asm_full_simp_tac is now more aggressive.
  8513      1. It will sometimes reorient premises if that increases their power to
  8514         simplify.
  8515      2. It does no longer proceed strictly from left to right but may also
  8516         rotate premises to achieve further simplification.
  8517      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8518      old Asm_full_simp_tac in that it does not rotate premises.
  8519   2. The simplifier now knows a little bit about nat-arithmetic.
  8520 
  8521 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8522 allows for selected deletion of wrappers, by introduction of names for
  8523 wrapper functionals.  This implies that addbefore, addSbefore,
  8524 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8525 and that adding two tactics with the same name overwrites the first
  8526 one (emitting a warning).
  8527   type wrapper = (int -> tactic) -> (int -> tactic)
  8528   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8529   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8530   delWrapper, delSWrapper: claset *  string            -> claset
  8531   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8532 
  8533 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8534 semantics; addbefore now affects only the unsafe part of step_tac
  8535 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8536 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8537 by Force_tac;
  8538 
  8539 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8540 compWrapper; added safe wrapper (and access functions for it);
  8541 
  8542 * HOL/split_all_tac is now much faster and fails if there is nothing
  8543 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8544 and the names of the automatically generated variables have changed.
  8545 split_all_tac has moved within claset() from unsafe wrappers to safe
  8546 wrappers, which means that !!-bound variables are split much more
  8547 aggressively, and safe_tac and clarify_tac now split such variables.
  8548 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8549 Note: the same holds for record_split_tac, which does the job of
  8550 split_all_tac for record fields.
  8551 
  8552 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8553 permanently to the default simpset using Addsplits just like
  8554 Addsimps. They can be removed via Delsplits just like
  8555 Delsimps. Lower-case versions are also available.
  8556 
  8557 * HOL/Simplifier: The rule split_if is now part of the default
  8558 simpset. This means that the simplifier will eliminate all occurrences
  8559 of if-then-else in the conclusion of a goal. To prevent this, you can
  8560 either remove split_if completely from the default simpset by
  8561 `Delsplits [split_if]' or remove it in a specific call of the
  8562 simplifier using `... delsplits [split_if]'.  You can also add/delete
  8563 other case splitting rules to/from the default simpset: every datatype
  8564 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  8565 t is the name of the datatype).
  8566 
  8567 * Classical reasoner / Simplifier combination: new force_tac (and
  8568 derivatives Force_tac, force) combines rewriting and classical
  8569 reasoning (and whatever other tools) similarly to auto_tac, but is
  8570 aimed to solve the given subgoal completely.
  8571 
  8572 
  8573 *** General ***
  8574 
  8575 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  8576 and `goalw': the theory is no longer needed as an explicit argument -
  8577 the current theory context is used; assumptions are no longer returned
  8578 at the ML-level unless one of them starts with ==> or !!; it is
  8579 recommended to convert to these new commands using isatool fixgoal
  8580 (backup your sources first!);
  8581 
  8582 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  8583 the current theory context, and 'theory' to lookup stored theories;
  8584 
  8585 * new theory section 'locale' for declaring constants, assumptions and
  8586 definitions that have local scope;
  8587 
  8588 * new theory section 'nonterminals' for purely syntactic types;
  8589 
  8590 * new theory section 'setup' for generic ML setup functions
  8591 (e.g. package initialization);
  8592 
  8593 * the distribution now includes Isabelle icons: see
  8594 lib/logo/isabelle-{small,tiny}.xpm;
  8595 
  8596 * isatool install - install binaries with absolute references to
  8597 ISABELLE_HOME/bin;
  8598 
  8599 * isatool logo -- create instances of the Isabelle logo (as EPS);
  8600 
  8601 * print mode 'emacs' reserved for Isamode;
  8602 
  8603 * support multiple print (ast) translations per constant name;
  8604 
  8605 * theorems involving oracles are now printed with a suffixed [!];
  8606 
  8607 
  8608 *** HOL ***
  8609 
  8610 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  8611 
  8612 * HOL/inductive package reorganized and improved: now supports mutual
  8613 definitions such as
  8614 
  8615   inductive EVEN ODD
  8616     intrs
  8617       null "0 : EVEN"
  8618       oddI "n : EVEN ==> Suc n : ODD"
  8619       evenI "n : ODD ==> Suc n : EVEN"
  8620 
  8621 new theorem list "elims" contains an elimination rule for each of the
  8622 recursive sets; inductive definitions now handle disjunctive premises
  8623 correctly (also ZF);
  8624 
  8625 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  8626 "mutual_induct" no longer exists - the induction rule is always
  8627 contained in "induct";
  8628 
  8629 
  8630 * HOL/datatype package re-implemented and greatly improved: now
  8631 supports mutually recursive datatypes such as
  8632 
  8633   datatype
  8634     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  8635             | SUM ('a aexp) ('a aexp)
  8636             | DIFF ('a aexp) ('a aexp)
  8637             | NUM 'a
  8638   and
  8639     'a bexp = LESS ('a aexp) ('a aexp)
  8640             | AND ('a bexp) ('a bexp)
  8641             | OR ('a bexp) ('a bexp)
  8642 
  8643 as well as indirectly recursive datatypes such as
  8644 
  8645   datatype
  8646     ('a, 'b) term = Var 'a
  8647                   | App 'b ((('a, 'b) term) list)
  8648 
  8649 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  8650 induction on mutually / indirectly recursive datatypes.
  8651 
  8652 Primrec equations are now stored in theory and can be accessed via
  8653 <function_name>.simps.
  8654 
  8655 INCOMPATIBILITIES:
  8656 
  8657   - Theories using datatypes must now have theory Datatype as an
  8658     ancestor.
  8659   - The specific <typename>.induct_tac no longer exists - use the
  8660     generic induct_tac instead.
  8661   - natE has been renamed to nat.exhaust - use exhaust_tac
  8662     instead of res_inst_tac ... natE. Note that the variable
  8663     names in nat.exhaust differ from the names in natE, this
  8664     may cause some "fragile" proofs to fail.
  8665   - The theorems split_<typename>_case and split_<typename>_case_asm
  8666     have been renamed to <typename>.split and <typename>.split_asm.
  8667   - Since default sorts of type variables are now handled correctly,
  8668     some datatype definitions may have to be annotated with explicit
  8669     sort constraints.
  8670   - Primrec definitions no longer require function name and type
  8671     of recursive argument.
  8672 
  8673 Consider using isatool fixdatatype to adapt your theories and proof
  8674 scripts to the new package (backup your sources first!).
  8675 
  8676 
  8677 * HOL/record package: considerably improved implementation; now
  8678 includes concrete syntax for record types, terms, updates; theorems
  8679 for surjective pairing and splitting !!-bound record variables; proof
  8680 support is as follows:
  8681 
  8682   1) standard conversions (selectors or updates applied to record
  8683 constructor terms) are part of the standard simpset;
  8684 
  8685   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  8686 made part of standard simpset and claset via addIffs;
  8687 
  8688   3) a tactic for record field splitting (record_split_tac) is part of
  8689 the standard claset (addSWrapper);
  8690 
  8691 To get a better idea about these rules you may retrieve them via
  8692 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  8693 the name of your record type.
  8694 
  8695 The split tactic 3) conceptually simplifies by the following rule:
  8696 
  8697   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  8698 
  8699 Thus any record variable that is bound by meta-all will automatically
  8700 blow up into some record constructor term, consequently the
  8701 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  8702 solve record problems automatically.
  8703 
  8704 
  8705 * reorganized the main HOL image: HOL/Integ and String loaded by
  8706 default; theory Main includes everything;
  8707 
  8708 * automatic simplification of integer sums and comparisons, using cancellation;
  8709 
  8710 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  8711 
  8712 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  8713 
  8714 * many new identities for unions, intersections, set difference, etc.;
  8715 
  8716 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  8717 called split_if, split_split, split_sum_case and split_nat_case (to go
  8718 with add/delsplits);
  8719 
  8720 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  8721 (?x::unit) = (); this is made part of the default simpset, which COULD
  8722 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  8723 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  8724 unit_abs_eta_conv is added in order to counter the effect of
  8725 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  8726 %u.f();
  8727 
  8728 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  8729 makes more sense);
  8730 
  8731 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8732   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8733   disjointness reasoning but breaking a few old proofs.
  8734 
  8735 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  8736 to 'converse' from 'inverse' (for compatibility with ZF and some
  8737 literature);
  8738 
  8739 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  8740 the well-founded relation;
  8741 
  8742 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8743     Compl A.  The "Compl" syntax remains available as input syntax for this
  8744     release ONLY.
  8745 
  8746 * HOL/Update: new theory of function updates:
  8747     f(a:=b) == %x. if x=a then b else f x
  8748 may also be iterated as in f(a:=b,c:=d,...);
  8749 
  8750 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8751 
  8752 * HOL/List:
  8753   - new function list_update written xs[i:=v] that updates the i-th
  8754     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8755   - new function `upt' written [i..j(] which generates the list
  8756     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8757     bound write [i..j], which is a shorthand for [i..j+1(].
  8758   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8759 
  8760 * HOL/Arith:
  8761   - removed 'pred' (predecessor) function;
  8762   - generalized some theorems about n-1;
  8763   - many new laws about "div" and "mod";
  8764   - new laws about greatest common divisors (see theory ex/Primes);
  8765 
  8766 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8767 instead of "inverse";
  8768 
  8769 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8770   of the multiset ordering;
  8771 
  8772 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8773   (not included by default);
  8774 
  8775 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8776 
  8777 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8778   programs, i.e. different program variables may have different types.
  8779 
  8780 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8781   [previously, this check worked only if the rewrite rule was unconditional]
  8782   Now rew can involve either definitions or equalities (either == or =).
  8783 
  8784 
  8785 *** ZF ***
  8786 
  8787 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8788   only the theorems proved on ZF.ML;
  8789 
  8790 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8791   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8792   disjointness reasoning but breaking a few old proofs.
  8793 
  8794 * ZF/Update: new theory of function updates
  8795     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8796   may also be iterated as in f(a:=b,c:=d,...);
  8797 
  8798 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8799 
  8800 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8801   [previously, this check worked only if the rewrite rule was unconditional]
  8802   Now rew can involve either definitions or equalities (either == or =).
  8803 
  8804 * case_tac provided for compatibility with HOL
  8805     (like the old excluded_middle_tac, but with subgoals swapped)
  8806 
  8807 
  8808 *** Internal programming interfaces ***
  8809 
  8810 * Pure: several new basic modules made available for general use, see
  8811 also src/Pure/README;
  8812 
  8813 * improved the theory data mechanism to support encapsulation (data
  8814 kind name replaced by private Object.kind, acting as authorization
  8815 key); new type-safe user interface via functor TheoryDataFun; generic
  8816 print_data function becomes basically useless;
  8817 
  8818 * removed global_names compatibility flag -- all theory declarations
  8819 are qualified by default;
  8820 
  8821 * module Pure/Syntax now offers quote / antiquote translation
  8822 functions (useful for Hoare logic etc. with implicit dependencies);
  8823 see HOL/ex/Antiquote for an example use;
  8824 
  8825 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8826 cterm -> thm;
  8827 
  8828 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8829 subgoal;
  8830 
  8831 * Display.print_goals function moved to Locale.print_goals;
  8832 
  8833 * standard print function for goals supports current_goals_markers
  8834 variable for marking begin of proof, end of proof, start of goal; the
  8835 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8836 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8837 for example;
  8838 
  8839 
  8840 
  8841 New in Isabelle98 (January 1998)
  8842 --------------------------------
  8843 
  8844 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8845 
  8846 * changed lexical syntax of terms / types: dots made part of long
  8847 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8848 
  8849 * simpset (and claset) reference variable replaced by functions
  8850 simpset / simpset_ref;
  8851 
  8852 * no longer supports theory aliases (via merge) and non-trivial
  8853 implicit merge of thms' signatures;
  8854 
  8855 * most internal names of constants changed due to qualified names;
  8856 
  8857 * changed Pure/Sequence interface (see Pure/seq.ML);
  8858 
  8859 
  8860 *** General Changes ***
  8861 
  8862 * hierachically structured name spaces (for consts, types, axms, thms
  8863 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8864 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8865 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8866 long_names for fully qualified output names; NOTE: ML programs
  8867 (special tactics, packages etc.) referring to internal names may have
  8868 to be adapted to cope with fully qualified names; in case of severe
  8869 backward campatibility problems try setting 'global_names' at compile
  8870 time to have enrything declared within a flat name space; one may also
  8871 fine tune name declarations in theories via the 'global' and 'local'
  8872 section;
  8873 
  8874 * reimplemented the implicit simpset and claset using the new anytype
  8875 data filed in signatures; references simpset:simpset ref etc. are
  8876 replaced by functions simpset:unit->simpset and
  8877 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8878 to patch your ML files accordingly;
  8879 
  8880 * HTML output now includes theory graph data for display with Java
  8881 applet or isatool browser; data generated automatically via isatool
  8882 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8883 
  8884 * defs may now be conditional; improved rewrite_goals_tac to handle
  8885 conditional equations;
  8886 
  8887 * defs now admits additional type arguments, using TYPE('a) syntax;
  8888 
  8889 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8890 creates a new theory node; implicit merge of thms' signatures is
  8891 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8892 transfer:theory->thm->thm in (rare) cases;
  8893 
  8894 * improved handling of draft signatures / theories; draft thms (and
  8895 ctyps, cterms) are automatically promoted to real ones;
  8896 
  8897 * slightly changed interfaces for oracles: admit many per theory, named
  8898 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8899 
  8900 * print_goals: optional output of const types (set show_consts and
  8901 show_types);
  8902 
  8903 * improved output of warnings (###) and errors (***);
  8904 
  8905 * subgoal_tac displays a warning if the new subgoal has type variables;
  8906 
  8907 * removed old README and Makefiles;
  8908 
  8909 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8910 
  8911 * removed obsolete init_pps and init_database;
  8912 
  8913 * deleted the obsolete tactical STATE, which was declared by
  8914     fun STATE tacfun st = tacfun st st;
  8915 
  8916 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8917 (which abbreviates $HOME);
  8918 
  8919 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8920 use isatool fixseq to adapt your ML programs (this works for fully
  8921 qualified references to the Sequence structure only!);
  8922 
  8923 * use_thy no longer requires writable current directory; it always
  8924 reloads .ML *and* .thy file, if either one is out of date;
  8925 
  8926 
  8927 *** Classical Reasoner ***
  8928 
  8929 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8930 tactics that use classical reasoning to simplify a subgoal without
  8931 splitting it into several subgoals;
  8932 
  8933 * Safe_tac: like safe_tac but uses the default claset;
  8934 
  8935 
  8936 *** Simplifier ***
  8937 
  8938 * added simplification meta rules:
  8939     (asm_)(full_)simplify: simpset -> thm -> thm;
  8940 
  8941 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8942 logics (again);
  8943 
  8944 * added prems argument to simplification procedures;
  8945 
  8946 * HOL, FOL, ZF: added infix function `addsplits':
  8947   instead of `<simpset> setloop (split_tac <thms>)'
  8948   you can simply write `<simpset> addsplits <thms>'
  8949 
  8950 
  8951 *** Syntax ***
  8952 
  8953 * TYPE('a) syntax for type reflection terms;
  8954 
  8955 * no longer handles consts with name "" -- declare as 'syntax' instead;
  8956 
  8957 * pretty printer: changed order of mixfix annotation preference (again!);
  8958 
  8959 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  8960 
  8961 
  8962 *** HOL ***
  8963 
  8964 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8965   with `addloop' of the simplifier to faciliate case splitting in premises.
  8966 
  8967 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  8968 
  8969 * HOL/Auth: new protocol proofs including some for the Internet
  8970   protocol TLS;
  8971 
  8972 * HOL/Map: new theory of `maps' a la VDM;
  8973 
  8974 * HOL/simplifier: simplification procedures nat_cancel_sums for
  8975 cancelling out common nat summands from =, <, <= (in)equalities, or
  8976 differences; simplification procedures nat_cancel_factor for
  8977 cancelling common factor from =, <, <= (in)equalities over natural
  8978 sums; nat_cancel contains both kinds of procedures, it is installed by
  8979 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  8980 
  8981 * HOL/simplifier: terms of the form
  8982   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  8983   are rewritten to
  8984   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  8985   and those of the form
  8986   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  8987   are rewritten to
  8988   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  8989 
  8990 * HOL/datatype
  8991   Each datatype `t' now comes with a theorem `split_t_case' of the form
  8992 
  8993   P(t_case f1 ... fn x) =
  8994      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  8995         ...
  8996        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  8997      )
  8998 
  8999   and a theorem `split_t_case_asm' of the form
  9000 
  9001   P(t_case f1 ... fn x) =
  9002     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  9003         ...
  9004        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  9005      )
  9006   which can be added to a simpset via `addsplits'. The existing theorems
  9007   expand_list_case and expand_option_case have been renamed to
  9008   split_list_case and split_option_case.
  9009 
  9010 * HOL/Arithmetic:
  9011   - `pred n' is automatically converted to `n-1'.
  9012     Users are strongly encouraged not to use `pred' any longer,
  9013     because it will disappear altogether at some point.
  9014   - Users are strongly encouraged to write "0 < n" rather than
  9015     "n ~= 0". Theorems and proof tools have been modified towards this
  9016     `standard'.
  9017 
  9018 * HOL/Lists:
  9019   the function "set_of_list" has been renamed "set" (and its theorems too);
  9020   the function "nth" now takes its arguments in the reverse order and
  9021   has acquired the infix notation "!" as in "xs!n".
  9022 
  9023 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  9024 
  9025 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  9026   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  9027 
  9028 * HOL/record: extensible records with schematic structural subtyping
  9029 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  9030 still lacks various theorems and concrete record syntax;
  9031 
  9032 
  9033 *** HOLCF ***
  9034 
  9035 * removed "axioms" and "generated by" sections;
  9036 
  9037 * replaced "ops" section by extended "consts" section, which is capable of
  9038   handling the continuous function space "->" directly;
  9039 
  9040 * domain package:
  9041   . proves theorems immediately and stores them in the theory,
  9042   . creates hierachical name space,
  9043   . now uses normal mixfix annotations (instead of cinfix...),
  9044   . minor changes to some names and values (for consistency),
  9045   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  9046   . separator between mutual domain defs: changed "," to "and",
  9047   . improved handling of sort constraints;  now they have to
  9048     appear on the left-hand side of the equations only;
  9049 
  9050 * fixed LAM <x,y,zs>.b syntax;
  9051 
  9052 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  9053 adm (%x. P (t x)), where P is chainfinite and t continuous;
  9054 
  9055 
  9056 *** FOL and ZF ***
  9057 
  9058 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9059   with `addloop' of the simplifier to faciliate case splitting in premises.
  9060 
  9061 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  9062 in HOL, they strip ALL and --> from proved theorems;
  9063 
  9064 
  9065 
  9066 New in Isabelle94-8 (May 1997)
  9067 ------------------------------
  9068 
  9069 *** General Changes ***
  9070 
  9071 * new utilities to build / run / maintain Isabelle etc. (in parts
  9072 still somewhat experimental); old Makefiles etc. still functional;
  9073 
  9074 * new 'Isabelle System Manual';
  9075 
  9076 * INSTALL text, together with ./configure and ./build scripts;
  9077 
  9078 * reimplemented type inference for greater efficiency, better error
  9079 messages and clean internal interface;
  9080 
  9081 * prlim command for dealing with lots of subgoals (an easier way of
  9082 setting goals_limit);
  9083 
  9084 
  9085 *** Syntax ***
  9086 
  9087 * supports alternative (named) syntax tables (parser and pretty
  9088 printer); internal interface is provided by add_modesyntax(_i);
  9089 
  9090 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  9091 be used in conjunction with the Isabelle symbol font; uses the
  9092 "symbols" syntax table;
  9093 
  9094 * added token_translation interface (may translate name tokens in
  9095 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  9096 the current print_mode); IMPORTANT: user print translation functions
  9097 are responsible for marking newly introduced bounds
  9098 (Syntax.mark_boundT);
  9099 
  9100 * token translations for modes "xterm" and "xterm_color" that display
  9101 names in bold, underline etc. or colors (which requires a color
  9102 version of xterm);
  9103 
  9104 * infixes may now be declared with names independent of their syntax;
  9105 
  9106 * added typed_print_translation (like print_translation, but may
  9107 access type of constant);
  9108 
  9109 
  9110 *** Classical Reasoner ***
  9111 
  9112 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  9113 some limitations.  Blast_tac...
  9114   + ignores addss, addbefore, addafter; this restriction is intrinsic
  9115   + ignores elimination rules that don't have the correct format
  9116         (the conclusion MUST be a formula variable)
  9117   + ignores types, which can make HOL proofs fail
  9118   + rules must not require higher-order unification, e.g. apply_type in ZF
  9119     [message "Function Var's argument not a bound variable" relates to this]
  9120   + its proof strategy is more general but can actually be slower
  9121 
  9122 * substitution with equality assumptions no longer permutes other
  9123 assumptions;
  9124 
  9125 * minor changes in semantics of addafter (now called addaltern); renamed
  9126 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  9127 (and access functions for it);
  9128 
  9129 * improved combination of classical reasoner and simplifier:
  9130   + functions for handling clasimpsets
  9131   + improvement of addss: now the simplifier is called _after_ the
  9132     safe steps.
  9133   + safe variant of addss called addSss: uses safe simplifications
  9134     _during_ the safe steps. It is more complete as it allows multiple
  9135     instantiations of unknowns (e.g. with slow_tac).
  9136 
  9137 *** Simplifier ***
  9138 
  9139 * added interface for simplification procedures (functions that
  9140 produce *proven* rewrite rules on the fly, depending on current
  9141 redex);
  9142 
  9143 * ordering on terms as parameter (used for ordered rewriting);
  9144 
  9145 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  9146 
  9147 * the solver is now split into a safe and an unsafe part.
  9148 This should be invisible for the normal user, except that the
  9149 functions setsolver and addsolver have been renamed to setSolver and
  9150 addSolver; added safe_asm_full_simp_tac;
  9151 
  9152 
  9153 *** HOL ***
  9154 
  9155 * a generic induction tactic `induct_tac' which works for all datatypes and
  9156 also for type `nat';
  9157 
  9158 * a generic case distinction tactic `exhaust_tac' which works for all
  9159 datatypes and also for type `nat';
  9160 
  9161 * each datatype comes with a function `size';
  9162 
  9163 * patterns in case expressions allow tuple patterns as arguments to
  9164 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  9165 
  9166 * primrec now also works with type nat;
  9167 
  9168 * recdef: a new declaration form, allows general recursive functions to be
  9169 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  9170 
  9171 * the constant for negation has been renamed from "not" to "Not" to
  9172 harmonize with FOL, ZF, LK, etc.;
  9173 
  9174 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  9175 infinite lists;
  9176 
  9177 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  9178 
  9179 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  9180 problems in commutative rings, using axiomatic type classes for + and *;
  9181 
  9182 * more examples in HOL/MiniML and HOL/Auth;
  9183 
  9184 * more default rewrite rules for quantifiers, union/intersection;
  9185 
  9186 * a new constant `arbitrary == @x.False';
  9187 
  9188 * HOLCF/IOA replaces old HOL/IOA;
  9189 
  9190 * HOLCF changes: derived all rules and arities
  9191   + axiomatic type classes instead of classes
  9192   + typedef instead of faking type definitions
  9193   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  9194   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  9195   + eliminated the types void, one, tr
  9196   + use unit lift and bool lift (with translations) instead of one and tr
  9197   + eliminated blift from Lift3.thy (use Def instead of blift)
  9198   all eliminated rules are derived as theorems --> no visible changes ;
  9199 
  9200 
  9201 *** ZF ***
  9202 
  9203 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  9204 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  9205 as ZF_cs addSIs [equalityI];
  9206 
  9207 
  9208 
  9209 New in Isabelle94-7 (November 96)
  9210 ---------------------------------
  9211 
  9212 * allowing negative levels (as offsets) in prlev and choplev;
  9213 
  9214 * super-linear speedup for large simplifications;
  9215 
  9216 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  9217 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  9218 FAIL); can suppress it using the command Delsimps (ex_simps @
  9219 all_simps); De Morgan laws are also now included, by default;
  9220 
  9221 * improved printing of ==>  :  ~:
  9222 
  9223 * new object-logic "Sequents" adds linear logic, while replacing LK
  9224 and Modal (thanks to Sara Kalvala);
  9225 
  9226 * HOL/Auth: correctness proofs for authentication protocols;
  9227 
  9228 * HOL: new auto_tac combines rewriting and classical reasoning (many
  9229 examples on HOL/Auth);
  9230 
  9231 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  9232 the rewriter and classical reasoner simultaneously;
  9233 
  9234 * function uresult no longer returns theorems in "standard" format;
  9235 regain previous version by: val uresult = standard o uresult;
  9236 
  9237 
  9238 
  9239 New in Isabelle94-6
  9240 -------------------
  9241 
  9242 * oracles -- these establish an interface between Isabelle and trusted
  9243 external reasoners, which may deliver results as theorems;
  9244 
  9245 * proof objects (in particular record all uses of oracles);
  9246 
  9247 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  9248 
  9249 * "constdefs" section in theory files;
  9250 
  9251 * "primrec" section (HOL) no longer requires names;
  9252 
  9253 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  9254 
  9255 
  9256 
  9257 New in Isabelle94-5
  9258 -------------------
  9259 
  9260 * reduced space requirements;
  9261 
  9262 * automatic HTML generation from theories;
  9263 
  9264 * theory files no longer require "..." (quotes) around most types;
  9265 
  9266 * new examples, including two proofs of the Church-Rosser theorem;
  9267 
  9268 * non-curried (1994) version of HOL is no longer distributed;
  9269 
  9270 
  9271 
  9272 New in Isabelle94-4
  9273 -------------------
  9274 
  9275 * greatly reduced space requirements;
  9276 
  9277 * theory files (.thy) no longer require \...\ escapes at line breaks;
  9278 
  9279 * searchable theorem database (see the section "Retrieving theorems" on
  9280 page 8 of the Reference Manual);
  9281 
  9282 * new examples, including Grabczewski's monumental case study of the
  9283 Axiom of Choice;
  9284 
  9285 * The previous version of HOL renamed to Old_HOL;
  9286 
  9287 * The new version of HOL (previously called CHOL) uses a curried syntax
  9288 for functions.  Application looks like f a b instead of f(a,b);
  9289 
  9290 * Mutually recursive inductive definitions finally work in HOL;
  9291 
  9292 * In ZF, pattern-matching on tuples is now available in all abstractions and
  9293 translates to the operator "split";
  9294 
  9295 
  9296 
  9297 New in Isabelle94-3
  9298 -------------------
  9299 
  9300 * new infix operator, addss, allowing the classical reasoner to
  9301 perform simplification at each step of its search.  Example:
  9302         fast_tac (cs addss ss)
  9303 
  9304 * a new logic, CHOL, the same as HOL, but with a curried syntax
  9305 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  9306 look like (a,b) instead of <a,b>;
  9307 
  9308 * PLEASE NOTE: CHOL will eventually replace HOL!
  9309 
  9310 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  9311 It translates to the operator "split".  A new theory of integers is available;
  9312 
  9313 * In ZF, integer numerals now denote two's-complement binary integers.
  9314 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  9315 
  9316 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  9317 of the Axiom of Choice;
  9318 
  9319 
  9320 
  9321 New in Isabelle94-2
  9322 -------------------
  9323 
  9324 * Significantly faster resolution;
  9325 
  9326 * the different sections in a .thy file can now be mixed and repeated
  9327 freely;
  9328 
  9329 * Database of theorems for FOL, HOL and ZF.  New
  9330 commands including qed, qed_goal and bind_thm store theorems in the database.
  9331 
  9332 * Simple database queries: return a named theorem (get_thm) or all theorems of
  9333 a given theory (thms_of), or find out what theory a theorem was proved in
  9334 (theory_of_thm);
  9335 
  9336 * Bugs fixed in the inductive definition and datatype packages;
  9337 
  9338 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  9339 and HOL_dup_cs obsolete;
  9340 
  9341 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  9342 have been removed;
  9343 
  9344 * Simpler definition of function space in ZF;
  9345 
  9346 * new results about cardinal and ordinal arithmetic in ZF;
  9347 
  9348 * 'subtype' facility in HOL for introducing new types as subsets of existing
  9349 types;
  9350 
  9351 :mode=text:wrap=hard:maxLineLen=72: