NEWS
author Andreas Lochbihler
Fri, 13 Apr 2012 13:29:55 +0200
changeset 48323 60da1ee5363f
parent 48298 0daa97ed1585
child 48324 598604c91036
permissions -rw-r--r--
NEWS
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Prover IDE (PIDE) improvements:
    10 
    11   - markup for bound variables
    12   - markup for types of term variables (e.g. displayed as tooltips)
    13   - support for user-defined Isar commands within the running session
    14   - improved support for Unicode outside original 16bit range
    15     e.g. glyph for \<A> (thanks to jEdit 4.5.1)
    16 
    17 * Updated and extended reference manuals ("isar-ref" and
    18 "implementation"); reduced remaining material in old "ref" manual.
    19 
    20 * Rule attributes in local theory declarations (e.g. locale or class)
    21 are now statically evaluated: the resulting theorem is stored instead
    22 of the original expression.  INCOMPATIBILITY in rare situations, where
    23 the historic accident of dynamic re-evaluation in interpretations
    24 etc. was exploited.
    25 
    26 * Commands 'lemmas' and 'theorems' allow local variables using 'for'
    27 declaration, and results are standardized before being stored.  Thus
    28 old-style "standard" after instantiation or composition of facts
    29 becomes obsolete.  Minor INCOMPATIBILITY, due to potential change of
    30 indices of schematic variables.
    31 
    32 * Renamed some inner syntax categories:
    33 
    34     num ~> num_token
    35     xnum ~> xnum_token
    36     xstr ~> str_token
    37 
    38 Minor INCOMPATIBILITY.  Note that in practice "num_const" or
    39 "num_position" etc. are mainly used instead (which also include
    40 position information via constraints).
    41 
    42 * Simplified configuration options for syntax ambiguity: see
    43 "syntax_ambiguity_warning" and "syntax_ambiguity_limit" in isar-ref
    44 manual.  Minor INCOMPATIBILITY.
    45 
    46 * Forward declaration of outer syntax keywords within the theory
    47 header -- minor INCOMPATIBILITY for user-defined commands.  Allow new
    48 commands to be used in the same theory where defined.
    49 
    50 * ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
    51 (not just JRE).
    52 
    53 
    54 *** Pure ***
    55 
    56 * 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 occurence (!)"
    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 * New theory HOL/Library/DAList provides an abstract type for association
   298   lists with distinct keys.
   299 
   300 * 'datatype' specifications allow explicit sort constraints.
   301 
   302 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
   303 use theory HOL/Library/Nat_Bijection instead.
   304 
   305 * Theory HOL/Library/RBT_Impl: Backing implementation of red-black trees is
   306 now inside the type class' local context. Names of affected operations and lemmas 
   307 have been prefixed by rbt_. INCOMPATIBILITY for theories working directly with
   308 raw red-black trees, adapt the names as follows:
   309 
   310   Operations:
   311   bulkload -> rbt_bulkload
   312   del_from_left -> rbt_del_from_left
   313   del_from_right -> rbt_del_from_right
   314   del -> rbt_del
   315   delete -> rbt_delete
   316   ins -> rbt_ins
   317   insert -> rbt_insert
   318   insertw -> rbt_insert_with
   319   insert_with_key -> rbt_insert_with_key
   320   map_entry -> rbt_map_entry
   321   lookup -> rbt_lookup
   322   sorted -> rbt_sorted
   323   tree_greater -> rbt_greater
   324   tree_less -> rbt_less
   325   tree_less_symbol -> rbt_less_symbol
   326   union -> rbt_union
   327   union_with -> rbt_union_with
   328   union_with_key -> rbt_union_with_key
   329 
   330   Lemmas:
   331   balance_left_sorted -> balance_left_rbt_sorted
   332   balance_left_tree_greater -> balance_left_rbt_greater
   333   balance_left_tree_less -> balance_left_rbt_less
   334   balance_right_sorted -> balance_right_rbt_sorted
   335   balance_right_tree_greater -> balance_right_rbt_greater
   336   balance_right_tree_less -> balance_right_rbt_less
   337   balance_sorted -> balance_rbt_sorted
   338   balance_tree_greater -> balance_rbt_greater
   339   balance_tree_less -> balance_rbt_less
   340   bulkload_is_rbt -> rbt_bulkload_is_rbt
   341   combine_sorted -> combine_rbt_sorted
   342   combine_tree_greater -> combine_rbt_greater
   343   combine_tree_less -> combine_rbt_less
   344   delete_in_tree -> rbt_delete_in_tree
   345   delete_is_rbt -> rbt_delete_is_rbt
   346   del_from_left_tree_greater -> rbt_del_from_left_rbt_greater
   347   del_from_left_tree_less -> rbt_del_from_left_rbt_less
   348   del_from_right_tree_greater -> rbt_del_from_right_rbt_greater
   349   del_from_right_tree_less -> rbt_del_from_right_rbt_less
   350   del_in_tree -> rbt_del_in_tree
   351   del_inv1_inv2 -> rbt_del_inv1_inv2
   352   del_sorted -> rbt_del_rbt_sorted
   353   del_tree_greater -> rbt_del_rbt_greater
   354   del_tree_less -> rbt_del_rbt_less
   355   dom_lookup_Branch -> dom_rbt_lookup_Branch
   356   entries_lookup -> entries_rbt_lookup
   357   finite_dom_lookup -> finite_dom_rbt_lookup
   358   insert_sorted -> rbt_insert_rbt_sorted
   359   insertw_is_rbt -> rbt_insertw_is_rbt
   360   insertwk_is_rbt -> rbt_insertwk_is_rbt
   361   insertwk_sorted -> rbt_insertwk_rbt_sorted
   362   insertw_sorted -> rbt_insertw_rbt_sorted
   363   ins_sorted -> ins_rbt_sorted
   364   ins_tree_greater -> ins_rbt_greater
   365   ins_tree_less -> ins_rbt_less
   366   is_rbt_sorted -> is_rbt_rbt_sorted
   367   lookup_balance -> rbt_lookup_balance
   368   lookup_bulkload -> rbt_lookup_rbt_bulkload
   369   lookup_delete -> rbt_lookup_rbt_delete
   370   lookup_Empty -> rbt_lookup_Empty
   371   lookup_from_in_tree -> rbt_lookup_from_in_tree
   372   lookup_in_tree -> rbt_lookup_in_tree
   373   lookup_ins -> rbt_lookup_ins
   374   lookup_insert -> rbt_lookup_rbt_insert
   375   lookup_insertw -> rbt_lookup_rbt_insertw
   376   lookup_insertwk -> rbt_lookup_rbt_insertwk
   377   lookup_keys -> rbt_lookup_keys
   378   lookup_map -> rbt_lookup_map
   379   lookup_map_entry -> rbt_lookup_rbt_map_entry
   380   lookup_tree_greater -> rbt_lookup_rbt_greater
   381   lookup_tree_less -> rbt_lookup_rbt_less
   382   lookup_union -> rbt_lookup_rbt_union
   383   map_entry_color_of -> rbt_map_entry_color_of
   384   map_entry_inv1 -> rbt_map_entry_inv1
   385   map_entry_inv2 -> rbt_map_entry_inv2
   386   map_entry_is_rbt -> rbt_map_entry_is_rbt
   387   map_entry_sorted -> rbt_map_entry_rbt_sorted
   388   map_entry_tree_greater -> rbt_map_entry_rbt_greater
   389   map_entry_tree_less -> rbt_map_entry_rbt_less
   390   map_tree_greater -> map_rbt_greater
   391   map_tree_less -> map_rbt_less
   392   map_sorted -> map_rbt_sorted
   393   paint_sorted -> paint_rbt_sorted
   394   paint_lookup -> paint_rbt_lookup
   395   paint_tree_greater -> paint_rbt_greater
   396   paint_tree_less -> paint_rbt_less
   397   sorted_entries -> rbt_sorted_entries
   398   tree_greater_eq_trans -> rbt_greater_eq_trans
   399   tree_greater_nit -> rbt_greater_nit
   400   tree_greater_prop -> rbt_greater_prop
   401   tree_greater_simps -> rbt_greater_simps
   402   tree_greater_trans -> rbt_greater_trans
   403   tree_less_eq_trans -> rbt_less_eq_trans
   404   tree_less_nit -> rbt_less_nit
   405   tree_less_prop -> rbt_less_prop
   406   tree_less_simps -> rbt_less_simps
   407   tree_less_trans -> rbt_less_trans
   408   tree_ord_props -> rbt_ord_props
   409   union_Branch -> rbt_union_Branch
   410   union_is_rbt -> rbt_union_is_rbt
   411   unionw_is_rbt -> rbt_unionw_is_rbt
   412   unionwk_is_rbt -> rbt_unionwk_is_rbt
   413   unionwk_sorted -> rbt_unionwk_rbt_sorted
   414 
   415 * Session HOL-Word: Discontinued many redundant theorems specific to
   416 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
   417 instead.
   418 
   419   word_sub_alt ~> word_sub_wi
   420   word_add_alt ~> word_add_def
   421   word_mult_alt ~> word_mult_def
   422   word_minus_alt ~> word_minus_def
   423   word_0_alt ~> word_0_wi
   424   word_1_alt ~> word_1_wi
   425   word_add_0 ~> add_0_left
   426   word_add_0_right ~> add_0_right
   427   word_mult_1 ~> mult_1_left
   428   word_mult_1_right ~> mult_1_right
   429   word_add_commute ~> add_commute
   430   word_add_assoc ~> add_assoc
   431   word_add_left_commute ~> add_left_commute
   432   word_mult_commute ~> mult_commute
   433   word_mult_assoc ~> mult_assoc
   434   word_mult_left_commute ~> mult_left_commute
   435   word_left_distrib ~> left_distrib
   436   word_right_distrib ~> right_distrib
   437   word_left_minus ~> left_minus
   438   word_diff_0_right ~> diff_0_right
   439   word_diff_self ~> diff_self
   440   word_sub_def ~> diff_minus
   441   word_diff_minus ~> diff_minus
   442   word_add_ac ~> add_ac
   443   word_mult_ac ~> mult_ac
   444   word_plus_ac0 ~> add_0_left add_0_right add_ac
   445   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
   446   word_order_trans ~> order_trans
   447   word_order_refl ~> order_refl
   448   word_order_antisym ~> order_antisym
   449   word_order_linear ~> linorder_linear
   450   lenw1_zero_neq_one ~> zero_neq_one
   451   word_number_of_eq ~> number_of_eq
   452   word_of_int_add_hom ~> wi_hom_add
   453   word_of_int_sub_hom ~> wi_hom_sub
   454   word_of_int_mult_hom ~> wi_hom_mult
   455   word_of_int_minus_hom ~> wi_hom_neg
   456   word_of_int_succ_hom ~> wi_hom_succ
   457   word_of_int_pred_hom ~> wi_hom_pred
   458   word_of_int_0_hom ~> word_0_wi
   459   word_of_int_1_hom ~> word_1_wi
   460 
   461 * Clarified attribute "mono_set": pure declaration without modifying
   462 the result of the fact expression.
   463 
   464 * "Transitive_Closure.ntrancl": bounded transitive closure on
   465 relations.
   466 
   467 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
   468 
   469 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
   470 
   471 * Theory Int: Discontinued many legacy theorems specific to type int.
   472 INCOMPATIBILITY, use the corresponding generic theorems instead.
   473 
   474   zminus_zminus ~> minus_minus
   475   zminus_0 ~> minus_zero
   476   zminus_zadd_distrib ~> minus_add_distrib
   477   zadd_commute ~> add_commute
   478   zadd_assoc ~> add_assoc
   479   zadd_left_commute ~> add_left_commute
   480   zadd_ac ~> add_ac
   481   zmult_ac ~> mult_ac
   482   zadd_0 ~> add_0_left
   483   zadd_0_right ~> add_0_right
   484   zadd_zminus_inverse2 ~> left_minus
   485   zmult_zminus ~> mult_minus_left
   486   zmult_commute ~> mult_commute
   487   zmult_assoc ~> mult_assoc
   488   zadd_zmult_distrib ~> left_distrib
   489   zadd_zmult_distrib2 ~> right_distrib
   490   zdiff_zmult_distrib ~> left_diff_distrib
   491   zdiff_zmult_distrib2 ~> right_diff_distrib
   492   zmult_1 ~> mult_1_left
   493   zmult_1_right ~> mult_1_right
   494   zle_refl ~> order_refl
   495   zle_trans ~> order_trans
   496   zle_antisym ~> order_antisym
   497   zle_linear ~> linorder_linear
   498   zless_linear ~> linorder_less_linear
   499   zadd_left_mono ~> add_left_mono
   500   zadd_strict_right_mono ~> add_strict_right_mono
   501   zadd_zless_mono ~> add_less_le_mono
   502   int_0_less_1 ~> zero_less_one
   503   int_0_neq_1 ~> zero_neq_one
   504   zless_le ~> less_le
   505   zpower_zadd_distrib ~> power_add
   506   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   507   zero_le_zpower_abs ~> zero_le_power_abs
   508 
   509 * Theory Deriv: Renamed
   510 
   511   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   512 
   513 * New "case_product" attribute to generate a case rule doing multiple
   514 case distinctions at the same time.  E.g.
   515 
   516   list.exhaust [case_product nat.exhaust]
   517 
   518 produces a rule which can be used to perform case distinction on both
   519 a list and a nat.
   520 
   521 * Improved code generation of multisets.
   522 
   523 * New diagnostic command find_unused_assms to find potentially superfluous
   524   assumptions in theorems using Quickcheck.
   525 
   526 * Quickcheck:
   527   - Quickcheck returns variable assignments as counterexamples, which
   528     allows to reveal the underspecification of functions under test.
   529     For example, refuting "hd xs = x", it presents the variable
   530     assignment xs = [] and x = a1 as a counterexample, assuming that
   531     any property is false whenever "hd []" occurs in it.
   532     These counterexample are marked as potentially spurious, as
   533     Quickcheck also returns "xs = []" as a counterexample to the
   534     obvious theorem "hd xs = hd xs".
   535     After finding a potentially spurious counterexample, Quickcheck
   536     continues searching for genuine ones.
   537     By default, Quickcheck shows potentially spurious and genuine
   538     counterexamples. The option "genuine_only" sets quickcheck to
   539     only show genuine counterexamples.
   540 
   541   - The command 'quickcheck_generator' creates random and exhaustive
   542     value generators for a given type and operations.
   543     It generates values by using the operations as if they were
   544     constructors of that type. 
   545 
   546   - Support for multisets.
   547 
   548   - Added "use_subtype" options.
   549   - Added "quickcheck_locale" configuration to specify how to process
   550     conjectures in a locale context.
   551 
   552 * Nitpick:
   553   - Fixed infinite loop caused by the 'peephole_optim' option and
   554     affecting 'rat' and 'real'.
   555 
   556 * Sledgehammer:
   557   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   558   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   559   - Renamed "sound" option to "strict".
   560 
   561 * Metis:
   562   - Added possibility to specify lambda translations scheme as a
   563     parenthesized argument (e.g., "by (metis (lifting) ...)").
   564 
   565 * SMT:
   566   - renamed "smt_fixed" option to "smt_read_only_certificates".
   567  
   568 * Command 'try0':
   569   - Renamed from 'try_methods'. INCOMPATIBILITY.
   570 
   571 * New "eventually_elim" method as a generalized variant of the
   572   eventually_elim* rules. Supports structured proofs.
   573 
   574 * HOL/TPTP: support to parse and import TPTP problems (all languages)
   575   into Isabelle/HOL.
   576 
   577 
   578 *** FOL ***
   579 
   580 * New "case_product" attribute (see HOL).
   581 
   582 
   583 *** ML ***
   584 
   585 * Antiquotation @{keyword "name"} produces a parser for outer syntax
   586 from a minor keyword introduced via theory header declaration.
   587 
   588 * Antiquotation @{command_spec "name"} produces the
   589 Outer_Syntax.command_spec from a major keyword introduced via theory
   590 header declaration; it can be passed to Outer_Syntax.command etc.
   591 
   592 * Local_Theory.define no longer hard-wires default theorem name
   593 "foo_def", but retains the binding as given.  If that is Binding.empty
   594 / Attrib.empty_binding, the result is not registered as user-level
   595 fact.  The Local_Theory.define_internal variant allows to specify a
   596 non-empty name (used for the foundation in the background theory),
   597 while omitting the fact binding in the user-context.  Potential
   598 INCOMPATIBILITY for derived definitional packages: need to specify
   599 naming policy for primitive definitions more explicitly.
   600 
   601 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
   602 conformance with similar operations in structure Term and Logic.
   603 
   604 * Antiquotation @{attributes [...]} embeds attribute source
   605 representation into the ML text, which is particularly useful with
   606 declarations like Local_Theory.note.
   607 
   608 * Structure Proof_Context follows standard naming scheme.  Old
   609 ProofContext has been discontinued.  INCOMPATIBILITY.
   610 
   611 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   612 change of semantics: update is applied to auxiliary local theory
   613 context as well.
   614 
   615 * Modernized some old-style infix operations:
   616 
   617   addeqcongs    ~> Simplifier.add_eqcong
   618   deleqcongs    ~> Simplifier.del_eqcong
   619   addcongs      ~> Simplifier.add_cong
   620   delcongs      ~> Simplifier.del_cong
   621   setmksimps    ~> Simplifier.set_mksimps
   622   setmkcong     ~> Simplifier.set_mkcong
   623   setmksym      ~> Simplifier.set_mksym
   624   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   625   settermless   ~> Simplifier.set_termless
   626   setsubgoaler  ~> Simplifier.set_subgoaler
   627   addsplits     ~> Splitter.add_split
   628   delsplits     ~> Splitter.del_split
   629 
   630 
   631 
   632 New in Isabelle2011-1 (October 2011)
   633 ------------------------------------
   634 
   635 *** General ***
   636 
   637 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   638 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   639 
   640   - Management of multiple theory files directly from the editor
   641     buffer store -- bypassing the file-system (no requirement to save
   642     files for checking).
   643 
   644   - Markup of formal entities within the text buffer, with semantic
   645     highlighting, tooltips and hyperlinks to jump to defining source
   646     positions.
   647 
   648   - Improved text rendering, with sub/superscripts in the source
   649     buffer (including support for copy/paste wrt. output panel, HTML
   650     theory output and other non-Isabelle text boxes).
   651 
   652   - Refined scheduling of proof checking and printing of results,
   653     based on interactive editor view.  (Note: jEdit folding and
   654     narrowing allows to restrict buffer perspectives explicitly.)
   655 
   656   - Reduced CPU performance requirements, usable on machines with few
   657     cores.
   658 
   659   - Reduced memory requirements due to pruning of unused document
   660     versions (garbage collection).
   661 
   662 See also ~~/src/Tools/jEdit/README.html for further information,
   663 including some remaining limitations.
   664 
   665 * Theory loader: source files are exclusively located via the master
   666 directory of each theory node (where the .thy file itself resides).
   667 The global load path (such as src/HOL/Library) has been discontinued.
   668 Note that the path element ~~ may be used to reference theories in the
   669 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   670 INCOMPATIBILITY.
   671 
   672 * Theory loader: source files are identified by content via SHA1
   673 digests.  Discontinued former path/modtime identification and optional
   674 ISABELLE_FILE_IDENT plugin scripts.
   675 
   676 * Parallelization of nested Isar proofs is subject to
   677 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   678 usedir option -Q.
   679 
   680 * Name space: former unsynchronized references are now proper
   681 configuration options, with more conventional names:
   682 
   683   long_names   ~> names_long
   684   short_names  ~> names_short
   685   unique_names ~> names_unique
   686 
   687 Minor INCOMPATIBILITY, need to declare options in context like this:
   688 
   689   declare [[names_unique = false]]
   690 
   691 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   692 that the result needs to be unique, which means fact specifications
   693 may have to be refined after enriching a proof context.
   694 
   695 * Attribute "case_names" has been refined: the assumptions in each case
   696 can be named now by following the case name with [name1 name2 ...].
   697 
   698 * Isabelle/Isar reference manual has been updated and extended:
   699   - "Synopsis" provides a catalog of main Isar language concepts.
   700   - Formal references in syntax diagrams, via @{rail} antiquotation.
   701   - Updated material from classic "ref" manual, notably about
   702     "Classical Reasoner".
   703 
   704 
   705 *** HOL ***
   706 
   707 * Class bot and top require underlying partial order rather than
   708 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   709 
   710 * Class complete_lattice: generalized a couple of lemmas from sets;
   711 generalized theorems INF_cong and SUP_cong.  New type classes for
   712 complete boolean algebras and complete linear orders.  Lemmas
   713 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   714 class complete_linorder.
   715 
   716 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   717 Sup_fun_def, Inf_apply, Sup_apply.
   718 
   719 Removed redundant lemmas (the right hand side gives hints how to
   720 replace them for (metis ...), or (simp only: ...) proofs):
   721 
   722   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   723   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   724   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   725   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   726   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   727   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   728   Inter_def ~> INF_def, image_def
   729   Union_def ~> SUP_def, image_def
   730   INT_eq ~> INF_def, and image_def
   731   UN_eq ~> SUP_def, and image_def
   732   INF_subset ~> INF_superset_mono [OF _ order_refl]
   733 
   734 More consistent and comprehensive names:
   735 
   736   INTER_eq_Inter_image ~> INF_def
   737   UNION_eq_Union_image ~> SUP_def
   738   INFI_def ~> INF_def
   739   SUPR_def ~> SUP_def
   740   INF_leI ~> INF_lower
   741   INF_leI2 ~> INF_lower2
   742   le_INFI ~> INF_greatest
   743   le_SUPI ~> SUP_upper
   744   le_SUPI2 ~> SUP_upper2
   745   SUP_leI ~> SUP_least
   746   INFI_bool_eq ~> INF_bool_eq
   747   SUPR_bool_eq ~> SUP_bool_eq
   748   INFI_apply ~> INF_apply
   749   SUPR_apply ~> SUP_apply
   750   INTER_def ~> INTER_eq
   751   UNION_def ~> UNION_eq
   752 
   753 INCOMPATIBILITY.
   754 
   755 * Renamed theory Complete_Lattice to Complete_Lattices.
   756 INCOMPATIBILITY.
   757 
   758 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   759 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   760 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   761 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   762 
   763 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   764 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   765 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   766 INCOMPATIBILITY.
   767 
   768 * Added syntactic classes "inf" and "sup" for the respective
   769 constants.  INCOMPATIBILITY: Changes in the argument order of the
   770 (mostly internal) locale predicates for some derived classes.
   771 
   772 * Theorem collections ball_simps and bex_simps do not contain theorems
   773 referring to UNION any longer; these have been moved to collection
   774 UN_ball_bex_simps.  INCOMPATIBILITY.
   775 
   776 * Theory Archimedean_Field: floor now is defined as parameter of a
   777 separate type class floor_ceiling.
   778 
   779 * Theory Finite_Set: more coherent development of fold_set locales:
   780 
   781     locale fun_left_comm ~> locale comp_fun_commute
   782     locale fun_left_comm_idem ~> locale comp_fun_idem
   783 
   784 Both use point-free characterization; interpretation proofs may need
   785 adjustment.  INCOMPATIBILITY.
   786 
   787 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   788 accordance with standard mathematical terminology. INCOMPATIBILITY.
   789 
   790 * Theory Complex_Main: The locale interpretations for the
   791 bounded_linear and bounded_bilinear locales have been removed, in
   792 order to reduce the number of duplicate lemmas. Users must use the
   793 original names for distributivity theorems, potential INCOMPATIBILITY.
   794 
   795   divide.add ~> add_divide_distrib
   796   divide.diff ~> diff_divide_distrib
   797   divide.setsum ~> setsum_divide_distrib
   798   mult.add_right ~> right_distrib
   799   mult.diff_right ~> right_diff_distrib
   800   mult_right.setsum ~> setsum_right_distrib
   801   mult_left.diff ~> left_diff_distrib
   802 
   803 * Theory Complex_Main: Several redundant theorems have been removed or
   804 replaced by more general versions. INCOMPATIBILITY.
   805 
   806   real_diff_def ~> minus_real_def
   807   real_divide_def ~> divide_real_def
   808   real_less_def ~> less_le
   809   real_abs_def ~> abs_real_def
   810   real_sgn_def ~> sgn_real_def
   811   real_mult_commute ~> mult_commute
   812   real_mult_assoc ~> mult_assoc
   813   real_mult_1 ~> mult_1_left
   814   real_add_mult_distrib ~> left_distrib
   815   real_zero_not_eq_one ~> zero_neq_one
   816   real_mult_inverse_left ~> left_inverse
   817   INVERSE_ZERO ~> inverse_zero
   818   real_le_refl ~> order_refl
   819   real_le_antisym ~> order_antisym
   820   real_le_trans ~> order_trans
   821   real_le_linear ~> linear
   822   real_le_eq_diff ~> le_iff_diff_le_0
   823   real_add_left_mono ~> add_left_mono
   824   real_mult_order ~> mult_pos_pos
   825   real_mult_less_mono2 ~> mult_strict_left_mono
   826   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   827   real_0_le_divide_iff ~> zero_le_divide_iff
   828   realpow_two_disj ~> power2_eq_iff
   829   real_squared_diff_one_factored ~> square_diff_one_factored
   830   realpow_two_diff ~> square_diff_square_factored
   831   reals_complete2 ~> complete_real
   832   real_sum_squared_expand ~> power2_sum
   833   exp_ln_eq ~> ln_unique
   834   expi_add ~> exp_add
   835   expi_zero ~> exp_zero
   836   lemma_DERIV_subst ~> DERIV_cong
   837   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   838   LIMSEQ_const ~> tendsto_const
   839   LIMSEQ_norm ~> tendsto_norm
   840   LIMSEQ_add ~> tendsto_add
   841   LIMSEQ_minus ~> tendsto_minus
   842   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   843   LIMSEQ_diff ~> tendsto_diff
   844   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   845   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   846   LIMSEQ_mult ~> tendsto_mult
   847   LIMSEQ_inverse ~> tendsto_inverse
   848   LIMSEQ_divide ~> tendsto_divide
   849   LIMSEQ_pow ~> tendsto_power
   850   LIMSEQ_setsum ~> tendsto_setsum
   851   LIMSEQ_setprod ~> tendsto_setprod
   852   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   853   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   854   LIMSEQ_imp_rabs ~> tendsto_rabs
   855   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   856   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   857   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   858   LIMSEQ_Complex ~> tendsto_Complex
   859   LIM_ident ~> tendsto_ident_at
   860   LIM_const ~> tendsto_const
   861   LIM_add ~> tendsto_add
   862   LIM_add_zero ~> tendsto_add_zero
   863   LIM_minus ~> tendsto_minus
   864   LIM_diff ~> tendsto_diff
   865   LIM_norm ~> tendsto_norm
   866   LIM_norm_zero ~> tendsto_norm_zero
   867   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   868   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   869   LIM_rabs ~> tendsto_rabs
   870   LIM_rabs_zero ~> tendsto_rabs_zero
   871   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   872   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   873   LIM_compose ~> tendsto_compose
   874   LIM_mult ~> tendsto_mult
   875   LIM_scaleR ~> tendsto_scaleR
   876   LIM_of_real ~> tendsto_of_real
   877   LIM_power ~> tendsto_power
   878   LIM_inverse ~> tendsto_inverse
   879   LIM_sgn ~> tendsto_sgn
   880   isCont_LIM_compose ~> isCont_tendsto_compose
   881   bounded_linear.LIM ~> bounded_linear.tendsto
   882   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   883   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   884   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   885   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   886   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   887   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   888 
   889 * Theory Complex_Main: The definition of infinite series was
   890 generalized.  Now it is defined on the type class {topological_space,
   891 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   892 
   893 * Theory Complex_Main: The complex exponential function "expi" is now
   894 a type-constrained abbreviation for "exp :: complex => complex"; thus
   895 several polymorphic lemmas about "exp" are now applicable to "expi".
   896 
   897 * Code generation:
   898 
   899   - Theory Library/Code_Char_ord provides native ordering of
   900     characters in the target language.
   901 
   902   - Commands code_module and code_library are legacy, use export_code
   903     instead.
   904 
   905   - Method "evaluation" is legacy, use method "eval" instead.
   906 
   907   - Legacy evaluator "SML" is deactivated by default.  May be
   908     reactivated by the following theory command:
   909 
   910       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   911 
   912 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   913 
   914 * New proof method "induction" that gives induction hypotheses the
   915 name "IH", thus distinguishing them from further hypotheses that come
   916 from rule induction.  The latter are still called "hyps".  Method
   917 "induction" is a thin wrapper around "induct" and follows the same
   918 syntax.
   919 
   920 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
   921 still available as a legacy feature for some time.
   922 
   923 * Nitpick:
   924   - Added "need" and "total_consts" options.
   925   - Reintroduced "show_skolems" option by popular demand.
   926   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   927     INCOMPATIBILITY.
   928 
   929 * Sledgehammer:
   930   - Use quasi-sound (and efficient) translations by default.
   931   - Added support for the following provers: E-ToFoF, LEO-II,
   932     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
   933   - Automatically preplay and minimize proofs before showing them if
   934     this can be done within reasonable time.
   935   - sledgehammer available_provers ~> sledgehammer supported_provers.
   936     INCOMPATIBILITY.
   937   - Added "preplay_timeout", "slicing", "type_enc", "sound",
   938     "max_mono_iters", and "max_new_mono_instances" options.
   939   - Removed "explicit_apply" and "full_types" options as well as "Full
   940     Types" Proof General menu item. INCOMPATIBILITY.
   941 
   942 * Metis:
   943   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   944   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
   945     INCOMPATIBILITY.
   946 
   947 * Command 'try':
   948   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
   949     "elim:" options. INCOMPATIBILITY.
   950   - Introduced 'try' that not only runs 'try_methods' but also
   951     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
   952 
   953 * Quickcheck:
   954   - Added "eval" option to evaluate terms for the found counterexample
   955     (currently only supported by the default (exhaustive) tester).
   956   - Added post-processing of terms to obtain readable counterexamples
   957     (currently only supported by the default (exhaustive) tester).
   958   - New counterexample generator quickcheck[narrowing] enables
   959     narrowing-based testing.  Requires the Glasgow Haskell compiler
   960     with its installation location defined in the Isabelle settings
   961     environment as ISABELLE_GHC.
   962   - Removed quickcheck tester "SML" based on the SML code generator
   963     (formly in HOL/Library).
   964 
   965 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
   966 use 'partial_function' instead.
   967 
   968 * Theory Library/Extended_Reals replaces now the positive extended
   969 reals found in probability theory. This file is extended by
   970 Multivariate_Analysis/Extended_Real_Limits.
   971 
   972 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
   973 from where it must be imported explicitly if it is really required.
   974 INCOMPATIBILITY.
   975 
   976 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
   977 been moved here.  INCOMPATIBILITY.
   978 
   979 * Theory Library/Saturated provides type of numbers with saturated
   980 arithmetic.
   981 
   982 * Theory Library/Product_Lattice defines a pointwise ordering for the
   983 product type 'a * 'b, and provides instance proofs for various order
   984 and lattice type classes.
   985 
   986 * Theory Library/Countable now provides the "countable_datatype" proof
   987 method for proving "countable" class instances for datatypes.
   988 
   989 * Theory Library/Cset_Monad allows do notation for computable sets
   990 (cset) via the generic monad ad-hoc overloading facility.
   991 
   992 * Library: Theories of common data structures are split into theories
   993 for implementation, an invariant-ensuring type, and connection to an
   994 abstract type. INCOMPATIBILITY.
   995 
   996   - RBT is split into RBT and RBT_Mapping.
   997   - AssocList is split and renamed into AList and AList_Mapping.
   998   - DList is split into DList_Impl, DList, and DList_Cset.
   999   - Cset is split into Cset and List_Cset.
  1000 
  1001 * Theory Library/Nat_Infinity has been renamed to
  1002 Library/Extended_Nat, with name changes of the following types and
  1003 constants:
  1004 
  1005   type inat   ~> type enat
  1006   Fin         ~> enat
  1007   Infty       ~> infinity (overloaded)
  1008   iSuc        ~> eSuc
  1009   the_Fin     ~> the_enat
  1010 
  1011 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
  1012 been renamed accordingly. INCOMPATIBILITY.
  1013 
  1014 * Session Multivariate_Analysis: The euclidean_space type class now
  1015 fixes a constant "Basis :: 'a set" consisting of the standard
  1016 orthonormal basis for the type. Users now have the option of
  1017 quantifying over this set instead of using the "basis" function, e.g.
  1018 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
  1019 
  1020 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
  1021 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
  1022 "Cart_nth" and "Cart_lambda" have been respectively renamed to
  1023 "vec_nth" and "vec_lambda"; theorems mentioning those names have
  1024 changed to match. Definition theorems for overloaded constants now use
  1025 the standard "foo_vec_def" naming scheme. A few other theorems have
  1026 been renamed as follows (INCOMPATIBILITY):
  1027 
  1028   Cart_eq          ~> vec_eq_iff
  1029   dist_nth_le_cart ~> dist_vec_nth_le
  1030   tendsto_vector   ~> vec_tendstoI
  1031   Cauchy_vector    ~> vec_CauchyI
  1032 
  1033 * Session Multivariate_Analysis: Several duplicate theorems have been
  1034 removed, and other theorems have been renamed or replaced with more
  1035 general versions. INCOMPATIBILITY.
  1036 
  1037   finite_choice ~> finite_set_choice
  1038   eventually_conjI ~> eventually_conj
  1039   eventually_and ~> eventually_conj_iff
  1040   eventually_false ~> eventually_False
  1041   setsum_norm ~> norm_setsum
  1042   Lim_sequentially ~> LIMSEQ_def
  1043   Lim_ident_at ~> LIM_ident
  1044   Lim_const ~> tendsto_const
  1045   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
  1046   Lim_neg ~> tendsto_minus
  1047   Lim_add ~> tendsto_add
  1048   Lim_sub ~> tendsto_diff
  1049   Lim_mul ~> tendsto_scaleR
  1050   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
  1051   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
  1052   Lim_linear ~> bounded_linear.tendsto
  1053   Lim_component ~> tendsto_euclidean_component
  1054   Lim_component_cart ~> tendsto_vec_nth
  1055   Lim_inner ~> tendsto_inner [OF tendsto_const]
  1056   dot_lsum ~> inner_setsum_left
  1057   dot_rsum ~> inner_setsum_right
  1058   continuous_cmul ~> continuous_scaleR [OF continuous_const]
  1059   continuous_neg ~> continuous_minus
  1060   continuous_sub ~> continuous_diff
  1061   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
  1062   continuous_mul ~> continuous_scaleR
  1063   continuous_inv ~> continuous_inverse
  1064   continuous_at_within_inv ~> continuous_at_within_inverse
  1065   continuous_at_inv ~> continuous_at_inverse
  1066   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
  1067   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
  1068   continuous_at_component ~> continuous_component [OF continuous_at_id]
  1069   continuous_on_neg ~> continuous_on_minus
  1070   continuous_on_sub ~> continuous_on_diff
  1071   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
  1072   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
  1073   continuous_on_mul ~> continuous_on_scaleR
  1074   continuous_on_mul_real ~> continuous_on_mult
  1075   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
  1076   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
  1077   continuous_on_inverse ~> continuous_on_inv
  1078   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
  1079   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
  1080   subset_interior ~> interior_mono
  1081   subset_closure ~> closure_mono
  1082   closure_univ ~> closure_UNIV
  1083   real_arch_lt ~> reals_Archimedean2
  1084   real_arch ~> reals_Archimedean3
  1085   real_abs_norm ~> abs_norm_cancel
  1086   real_abs_sub_norm ~> norm_triangle_ineq3
  1087   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
  1088 
  1089 * Session HOL-Probability:
  1090   - Caratheodory's extension lemma is now proved for ring_of_sets.
  1091   - Infinite products of probability measures are now available.
  1092   - Sigma closure is independent, if the generator is independent
  1093   - Use extended reals instead of positive extended
  1094     reals. INCOMPATIBILITY.
  1095 
  1096 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
  1097 
  1098   expand_fun_below ~> fun_below_iff
  1099   below_fun_ext ~> fun_belowI
  1100   expand_cfun_eq ~> cfun_eq_iff
  1101   ext_cfun ~> cfun_eqI
  1102   expand_cfun_below ~> cfun_below_iff
  1103   below_cfun_ext ~> cfun_belowI
  1104   monofun_fun_fun ~> fun_belowD
  1105   monofun_fun_arg ~> monofunE
  1106   monofun_lub_fun ~> adm_monofun [THEN admD]
  1107   cont_lub_fun ~> adm_cont [THEN admD]
  1108   cont2cont_Rep_CFun ~> cont2cont_APP
  1109   cont_Rep_CFun_app ~> cont_APP_app
  1110   cont_Rep_CFun_app_app ~> cont_APP_app_app
  1111   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
  1112   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
  1113   contlub_cfun ~> lub_APP [symmetric]
  1114   contlub_LAM ~> lub_LAM [symmetric]
  1115   thelubI ~> lub_eqI
  1116   UU_I ~> bottomI
  1117   lift_distinct1 ~> lift.distinct(1)
  1118   lift_distinct2 ~> lift.distinct(2)
  1119   Def_not_UU ~> lift.distinct(2)
  1120   Def_inject ~> lift.inject
  1121   below_UU_iff ~> below_bottom_iff
  1122   eq_UU_iff ~> eq_bottom_iff
  1123 
  1124 
  1125 *** Document preparation ***
  1126 
  1127 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
  1128 isar-ref manual, both for description and actual application of the
  1129 same.
  1130 
  1131 * Antiquotation @{value} evaluates the given term and presents its
  1132 result.
  1133 
  1134 * Antiquotations: term style "isub" provides ad-hoc conversion of
  1135 variables x1, y23 into subscripted form x\<^isub>1,
  1136 y\<^isub>2\<^isub>3.
  1137 
  1138 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
  1139 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
  1140 
  1141 * Localized \isabellestyle switch can be used within blocks or groups
  1142 like this:
  1143 
  1144   \isabellestyle{it}  %preferred default
  1145   {\isabellestylett @{text "typewriter stuff"}}
  1146 
  1147 * Discontinued special treatment of hard tabulators.  Implicit
  1148 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
  1149 layouts.
  1150 
  1151 
  1152 *** ML ***
  1153 
  1154 * The inner syntax of sort/type/term/prop supports inlined YXML
  1155 representations within quoted string tokens.  By encoding logical
  1156 entities via Term_XML (in ML or Scala) concrete syntax can be
  1157 bypassed, which is particularly useful for producing bits of text
  1158 under external program control.
  1159 
  1160 * Antiquotations for ML and document preparation are managed as theory
  1161 data, which requires explicit setup.
  1162 
  1163 * Isabelle_Process.is_active allows tools to check if the official
  1164 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
  1165 (better known as Proof General).
  1166 
  1167 * Structure Proof_Context follows standard naming scheme.  Old
  1168 ProofContext is still available for some time as legacy alias.
  1169 
  1170 * Structure Timing provides various operations for timing; supersedes
  1171 former start_timing/end_timing etc.
  1172 
  1173 * Path.print is the official way to show file-system paths to users
  1174 (including quotes etc.).
  1175 
  1176 * Inner syntax: identifiers in parse trees of generic categories
  1177 "logic", "aprop", "idt" etc. carry position information (disguised as
  1178 type constraints).  Occasional INCOMPATIBILITY with non-compliant
  1179 translations that choke on unexpected type constraints.  Positions can
  1180 be stripped in ML translations via Syntax.strip_positions /
  1181 Syntax.strip_positions_ast, or via the syntax constant
  1182 "_strip_positions" within parse trees.  As last resort, positions can
  1183 be disabled via the configuration option Syntax.positions, which is
  1184 called "syntax_positions" in Isar attribute syntax.
  1185 
  1186 * Discontinued special status of various ML structures that contribute
  1187 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
  1188 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
  1189 refer directly to Ast.Constant, Lexicon.is_identifier,
  1190 Syntax_Trans.mk_binder_tr etc.
  1191 
  1192 * Typed print translation: discontinued show_sorts argument, which is
  1193 already available via context of "advanced" translation.
  1194 
  1195 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
  1196 goal states; body tactic needs to address all subgoals uniformly.
  1197 
  1198 * Slightly more special eq_list/eq_set, with shortcut involving
  1199 pointer equality (assumes that eq relation is reflexive).
  1200 
  1201 * Classical tactics use proper Proof.context instead of historic types
  1202 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  1203 operate directly on Proof.context.  Raw type claset retains its use as
  1204 snapshot of the classical context, which can be recovered via
  1205 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  1206 INCOMPATIBILITY, classical tactics and derived proof methods require
  1207 proper Proof.context.
  1208 
  1209 
  1210 *** System ***
  1211 
  1212 * Discontinued support for Poly/ML 5.2, which was the last version
  1213 without proper multithreading and TimeLimit implementation.
  1214 
  1215 * Discontinued old lib/scripts/polyml-platform, which has been
  1216 obsolete since Isabelle2009-2.
  1217 
  1218 * Various optional external tools are referenced more robustly and
  1219 uniformly by explicit Isabelle settings as follows:
  1220 
  1221   ISABELLE_CSDP   (formerly CSDP_EXE)
  1222   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  1223   ISABELLE_OCAML  (formerly EXEC_OCAML)
  1224   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  1225   ISABELLE_YAP    (formerly EXEC_YAP)
  1226 
  1227 Note that automated detection from the file-system or search path has
  1228 been discontinued.  INCOMPATIBILITY.
  1229 
  1230 * Scala layer provides JVM method invocation service for static
  1231 methods of type (String)String, see Invoke_Scala.method in ML.  For
  1232 example:
  1233 
  1234   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  1235 
  1236 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  1237 this allows to pass structured values between ML and Scala.
  1238 
  1239 * The IsabelleText fonts includes some further glyphs to support the
  1240 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  1241 installed a local copy (which is normally *not* required) need to
  1242 delete or update it from ~~/lib/fonts/.
  1243 
  1244 
  1245 
  1246 New in Isabelle2011 (January 2011)
  1247 ----------------------------------
  1248 
  1249 *** General ***
  1250 
  1251 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  1252 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  1253 useful tooltips and hyperlinks produced from its static analysis.  The
  1254 bundled component provides an executable Isabelle tool that can be run
  1255 like this:
  1256 
  1257   Isabelle2011/bin/isabelle jedit
  1258 
  1259 * Significantly improved Isabelle/Isar implementation manual.
  1260 
  1261 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  1262 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  1263 while the default heap location within that directory lacks that extra
  1264 suffix.  This isolates multiple Isabelle installations from each
  1265 other, avoiding problems with old settings in new versions.
  1266 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  1267 
  1268 * Source files are always encoded as UTF-8, instead of old-fashioned
  1269 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  1270 the following package declarations:
  1271 
  1272   \usepackage[utf8]{inputenc}
  1273   \usepackage{textcomp}
  1274 
  1275 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  1276 a Unicode character is treated as a single symbol, not a sequence of
  1277 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  1278 contain symbols without further backslash escapes, Unicode can now be
  1279 used here as well.  Recall that Symbol.explode in ML provides a
  1280 consistent view on symbols, while raw explode (or String.explode)
  1281 merely give a byte-oriented representation.
  1282 
  1283 * Theory loader: source files are primarily located via the master
  1284 directory of each theory node (where the .thy file itself resides).
  1285 The global load path is still partially available as legacy feature.
  1286 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  1287 explicit paths, relatively to the theory.
  1288 
  1289 * Special treatment of ML file names has been discontinued.
  1290 Historically, optional extensions .ML or .sml were added on demand --
  1291 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  1292 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  1293 
  1294 * Various options that affect pretty printing etc. are now properly
  1295 handled within the context via configuration options, instead of
  1296 unsynchronized references or print modes.  There are both ML Config.T
  1297 entities and Isar declaration attributes to access these.
  1298 
  1299   ML (Config.T)                 Isar (attribute)
  1300 
  1301   eta_contract                  eta_contract
  1302   show_brackets                 show_brackets
  1303   show_sorts                    show_sorts
  1304   show_types                    show_types
  1305   show_question_marks           show_question_marks
  1306   show_consts                   show_consts
  1307   show_abbrevs                  show_abbrevs
  1308 
  1309   Syntax.ast_trace              syntax_ast_trace
  1310   Syntax.ast_stat               syntax_ast_stat
  1311   Syntax.ambiguity_level        syntax_ambiguity_level
  1312 
  1313   Goal_Display.goals_limit      goals_limit
  1314   Goal_Display.show_main_goal   show_main_goal
  1315 
  1316   Method.rule_trace             rule_trace
  1317 
  1318   Thy_Output.display            thy_output_display
  1319   Thy_Output.quotes             thy_output_quotes
  1320   Thy_Output.indent             thy_output_indent
  1321   Thy_Output.source             thy_output_source
  1322   Thy_Output.break              thy_output_break
  1323 
  1324 Note that corresponding "..._default" references in ML may only be
  1325 changed globally at the ROOT session setup, but *not* within a theory.
  1326 The option "show_abbrevs" supersedes the former print mode
  1327 "no_abbrevs" with inverted meaning.
  1328 
  1329 * More systematic naming of some configuration options.
  1330 INCOMPATIBILITY.
  1331 
  1332   trace_simp  ~>  simp_trace
  1333   debug_simp  ~>  simp_debug
  1334 
  1335 * Support for real valued configuration options, using simplistic
  1336 floating-point notation that coincides with the inner syntax for
  1337 float_token.
  1338 
  1339 * Support for real valued preferences (with approximative PGIP type):
  1340 front-ends need to accept "pgint" values in float notation.
  1341 INCOMPATIBILITY.
  1342 
  1343 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  1344 DejaVu Sans.
  1345 
  1346 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  1347 
  1348 
  1349 *** Pure ***
  1350 
  1351 * Command 'type_synonym' (with single argument) replaces somewhat
  1352 outdated 'types', which is still available as legacy feature for some
  1353 time.
  1354 
  1355 * Command 'nonterminal' (with 'and' separated list of arguments)
  1356 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  1357 
  1358 * Command 'notepad' replaces former 'example_proof' for
  1359 experimentation in Isar without any result.  INCOMPATIBILITY.
  1360 
  1361 * Locale interpretation commands 'interpret' and 'sublocale' accept
  1362 lists of equations to map definitions in a locale to appropriate
  1363 entities in the context of the interpretation.  The 'interpretation'
  1364 command already provided this functionality.
  1365 
  1366 * Diagnostic command 'print_dependencies' prints the locale instances
  1367 that would be activated if the specified expression was interpreted in
  1368 the current context.  Variant "print_dependencies!" assumes a context
  1369 without interpretations.
  1370 
  1371 * Diagnostic command 'print_interps' prints interpretations in proofs
  1372 in addition to interpretations in theories.
  1373 
  1374 * Discontinued obsolete 'global' and 'local' commands to manipulate
  1375 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  1376 Sign.root_path and Sign.local_path may be applied directly where this
  1377 feature is still required for historical reasons.
  1378 
  1379 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  1380 'definition' instead.
  1381 
  1382 * The "prems" fact, which refers to the accidental collection of
  1383 foundational premises in the context, is now explicitly marked as
  1384 legacy feature and will be discontinued soon.  Consider using "assms"
  1385 of the head statement or reference facts by explicit names.
  1386 
  1387 * Document antiquotations @{class} and @{type} print classes and type
  1388 constructors.
  1389 
  1390 * Document antiquotation @{file} checks file/directory entries within
  1391 the local file system.
  1392 
  1393 
  1394 *** HOL ***
  1395 
  1396 * Coercive subtyping: functions can be declared as coercions and type
  1397 inference will add them as necessary upon input of a term.  Theory
  1398 Complex_Main declares real :: nat => real and real :: int => real as
  1399 coercions. A coercion function f is declared like this:
  1400 
  1401   declare [[coercion f]]
  1402 
  1403 To lift coercions through type constructors (e.g. from nat => real to
  1404 nat list => real list), map functions can be declared, e.g.
  1405 
  1406   declare [[coercion_map map]]
  1407 
  1408 Currently coercion inference is activated only in theories including
  1409 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1410 the configuration option "coercion_enabled", e.g. it can be enabled in
  1411 other theories like this:
  1412 
  1413   declare [[coercion_enabled]]
  1414 
  1415 * Command 'partial_function' provides basic support for recursive
  1416 function definitions over complete partial orders.  Concrete instances
  1417 are provided for i) the option type, ii) tail recursion on arbitrary
  1418 types, and iii) the heap monad of Imperative_HOL.  See
  1419 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1420 for examples.
  1421 
  1422 * Function package: f.psimps rules are no longer implicitly declared
  1423 as [simp].  INCOMPATIBILITY.
  1424 
  1425 * Datatype package: theorems generated for executable equality (class
  1426 "eq") carry proper names and are treated as default code equations.
  1427 
  1428 * Inductive package: now offers command 'inductive_simps' to
  1429 automatically derive instantiated and simplified equations for
  1430 inductive predicates, similar to 'inductive_cases'.
  1431 
  1432 * Command 'enriched_type' allows to register properties of the
  1433 functorial structure of types.
  1434 
  1435 * Improved infrastructure for term evaluation using code generator
  1436 techniques, in particular static evaluation conversions.
  1437 
  1438 * Code generator: Scala (2.8 or higher) has been added to the target
  1439 languages.
  1440 
  1441 * Code generator: globbing constant expressions "*" and "Theory.*"
  1442 have been replaced by the more idiomatic "_" and "Theory._".
  1443 INCOMPATIBILITY.
  1444 
  1445 * Code generator: export_code without explicit file declaration prints
  1446 to standard output.  INCOMPATIBILITY.
  1447 
  1448 * Code generator: do not print function definitions for case
  1449 combinators any longer.
  1450 
  1451 * Code generator: simplification with rules determined with
  1452 src/Tools/Code/code_simp.ML and method "code_simp".
  1453 
  1454 * Code generator for records: more idiomatic representation of record
  1455 types.  Warning: records are not covered by ancient SML code
  1456 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1457 rep_datatype declaration helps to succeed then:
  1458 
  1459   record 'a foo = ...
  1460   ...
  1461   rep_datatype foo_ext ...
  1462 
  1463 * Records: logical foundation type for records does not carry a
  1464 '_type' suffix any longer (obsolete due to authentic syntax).
  1465 INCOMPATIBILITY.
  1466 
  1467 * Quickcheck now by default uses exhaustive testing instead of random
  1468 testing.  Random testing can be invoked by "quickcheck [random]",
  1469 exhaustive testing by "quickcheck [exhaustive]".
  1470 
  1471 * Quickcheck instantiates polymorphic types with small finite
  1472 datatypes by default. This enables a simple execution mechanism to
  1473 handle quantifiers and function equality over the finite datatypes.
  1474 
  1475 * Quickcheck random generator has been renamed from "code" to
  1476 "random".  INCOMPATIBILITY.
  1477 
  1478 * Quickcheck now has a configurable time limit which is set to 30
  1479 seconds by default. This can be changed by adding [timeout = n] to the
  1480 quickcheck command. The time limit for Auto Quickcheck is still set
  1481 independently.
  1482 
  1483 * Quickcheck in locales considers interpretations of that locale for
  1484 counter example search.
  1485 
  1486 * Sledgehammer:
  1487   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1488     method. See the Sledgehammer manual for details ("isabelle doc
  1489     sledgehammer").
  1490   - Renamed commands:
  1491     sledgehammer atp_info ~> sledgehammer running_provers
  1492     sledgehammer atp_kill ~> sledgehammer kill_provers
  1493     sledgehammer available_atps ~> sledgehammer available_provers
  1494     INCOMPATIBILITY.
  1495   - Renamed options:
  1496     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1497     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1498     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1499     (and "ms" and "min" are no longer supported)
  1500     INCOMPATIBILITY.
  1501 
  1502 * Nitpick:
  1503   - Renamed options:
  1504     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1505     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1506     INCOMPATIBILITY.
  1507   - Added support for partial quotient types.
  1508   - Added local versions of the "Nitpick.register_xxx" functions.
  1509   - Added "whack" option.
  1510   - Allow registration of quotient types as codatatypes.
  1511   - Improved "merge_type_vars" option to merge more types.
  1512   - Removed unsound "fast_descrs" option.
  1513   - Added custom symmetry breaking for datatypes, making it possible to reach
  1514     higher cardinalities.
  1515   - Prevent the expansion of too large definitions.
  1516 
  1517 * Proof methods "metis" and "meson" now have configuration options
  1518 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1519 to diagnose these tools. E.g.
  1520 
  1521     using [[metis_trace = true]]
  1522 
  1523 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1524 manually as command 'solve_direct'.
  1525 
  1526 * The default SMT solver Z3 must be enabled explicitly (due to
  1527 licensing issues) by setting the environment variable
  1528 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1529 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1530 changing the SMT solver is done via the configuration option
  1531 "smt_solver".
  1532 
  1533 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1534 i.e. "remote_cvc3" and "remote_z3".
  1535 
  1536 * Added basic SMT support for datatypes, records, and typedefs using
  1537 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1538 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1539 support for a similar behavior).  Minor INCOMPATIBILITY.
  1540 
  1541 * Changed SMT configuration options:
  1542   - Renamed:
  1543     z3_proofs ~> smt_oracle (with inverted meaning)
  1544     z3_trace_assms ~> smt_trace_used_facts
  1545     INCOMPATIBILITY.
  1546   - Added:
  1547     smt_verbose
  1548     smt_random_seed
  1549     smt_datatypes
  1550     smt_infer_triggers
  1551     smt_monomorph_limit
  1552     cvc3_options
  1553     remote_cvc3_options
  1554     remote_z3_options
  1555     yices_options
  1556 
  1557 * Boogie output files (.b2i files) need to be declared in the theory
  1558 header.
  1559 
  1560 * Simplification procedure "list_to_set_comprehension" rewrites list
  1561 comprehensions applied to List.set to set comprehensions.  Occasional
  1562 INCOMPATIBILITY, may be deactivated like this:
  1563 
  1564   declare [[simproc del: list_to_set_comprehension]]
  1565 
  1566 * Removed old version of primrec package.  INCOMPATIBILITY.
  1567 
  1568 * Removed simplifier congruence rule of "prod_case", as has for long
  1569 been the case with "split".  INCOMPATIBILITY.
  1570 
  1571 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1572 
  1573 * Removed [split_format ... and ... and ...] version of
  1574 [split_format].  Potential INCOMPATIBILITY.
  1575 
  1576 * Predicate "sorted" now defined inductively, with nice induction
  1577 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1578 
  1579 * Constant "contents" renamed to "the_elem", to free the generic name
  1580 contents for other uses.  INCOMPATIBILITY.
  1581 
  1582 * Renamed class eq and constant eq (for code generation) to class
  1583 equal and constant equal, plus renaming of related facts and various
  1584 tuning.  INCOMPATIBILITY.
  1585 
  1586 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1587 
  1588 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1589 INCOMPATIBILITY.
  1590 
  1591 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1592 avoid confusion with finite sets.  INCOMPATIBILITY.
  1593 
  1594 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1595 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1596 for congruent(2)).
  1597 
  1598 * Some previously unqualified names have been qualified:
  1599 
  1600   types
  1601     bool ~> HOL.bool
  1602     nat ~> Nat.nat
  1603 
  1604   constants
  1605     Trueprop ~> HOL.Trueprop
  1606     True ~> HOL.True
  1607     False ~> HOL.False
  1608     op & ~> HOL.conj
  1609     op | ~> HOL.disj
  1610     op --> ~> HOL.implies
  1611     op = ~> HOL.eq
  1612     Not ~> HOL.Not
  1613     The ~> HOL.The
  1614     All ~> HOL.All
  1615     Ex ~> HOL.Ex
  1616     Ex1 ~> HOL.Ex1
  1617     Let ~> HOL.Let
  1618     If ~> HOL.If
  1619     Ball ~> Set.Ball
  1620     Bex ~> Set.Bex
  1621     Suc ~> Nat.Suc
  1622     Pair ~> Product_Type.Pair
  1623     fst ~> Product_Type.fst
  1624     snd ~> Product_Type.snd
  1625     curry ~> Product_Type.curry
  1626     op : ~> Set.member
  1627     Collect ~> Set.Collect
  1628 
  1629 INCOMPATIBILITY.
  1630 
  1631 * More canonical naming convention for some fundamental definitions:
  1632 
  1633     bot_bool_eq ~> bot_bool_def
  1634     top_bool_eq ~> top_bool_def
  1635     inf_bool_eq ~> inf_bool_def
  1636     sup_bool_eq ~> sup_bool_def
  1637     bot_fun_eq  ~> bot_fun_def
  1638     top_fun_eq  ~> top_fun_def
  1639     inf_fun_eq  ~> inf_fun_def
  1640     sup_fun_eq  ~> sup_fun_def
  1641 
  1642 INCOMPATIBILITY.
  1643 
  1644 * More stylized fact names:
  1645 
  1646   expand_fun_eq ~> fun_eq_iff
  1647   expand_set_eq ~> set_eq_iff
  1648   set_ext       ~> set_eqI
  1649   nat_number    ~> eval_nat_numeral
  1650 
  1651 INCOMPATIBILITY.
  1652 
  1653 * Refactoring of code-generation specific operations in theory List:
  1654 
  1655   constants
  1656     null ~> List.null
  1657 
  1658   facts
  1659     mem_iff ~> member_def
  1660     null_empty ~> null_def
  1661 
  1662 INCOMPATIBILITY.  Note that these were not supposed to be used
  1663 regularly unless for striking reasons; their main purpose was code
  1664 generation.
  1665 
  1666 Various operations from the Haskell prelude are used for generating
  1667 Haskell code.
  1668 
  1669 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1670 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1671 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1672 
  1673 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1674 "*" and "+" respectively.  INCOMPATIBILITY.
  1675 
  1676 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1677 "Sum_Type.Plus" instead.
  1678 
  1679 * Constant "split" has been merged with constant "prod_case"; names of
  1680 ML functions, facts etc. involving split have been retained so far,
  1681 though.  INCOMPATIBILITY.
  1682 
  1683 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1684 instead.  INCOMPATIBILITY.
  1685 
  1686 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1687 INCOMPATIBILITY.
  1688 
  1689 * Former theory Library/Enum is now part of the HOL-Main image.
  1690 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1691 referred to by its qualified name.
  1692 
  1693   enum    ~>  Enum.enum
  1694   nlists  ~>  Enum.nlists
  1695   product ~>  Enum.product
  1696 
  1697 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1698 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1699 INCOMPATIBILITY.
  1700 
  1701 * Theory Library/SetsAndFunctions has been split into
  1702 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1703 for instance definitions for functions; various improvements.
  1704 INCOMPATIBILITY.
  1705 
  1706 * Theory Library/Multiset provides stable quicksort implementation of
  1707 sort_key.
  1708 
  1709 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1710 INCOMPATIBILITY.
  1711 
  1712 * Session Multivariate_Analysis: introduced a type class for euclidean
  1713 space.  Most theorems are now stated in terms of euclidean spaces
  1714 instead of finite cartesian products.
  1715 
  1716   types
  1717     real ^ 'n ~>  'a::real_vector
  1718               ~>  'a::euclidean_space
  1719               ~>  'a::ordered_euclidean_space
  1720         (depends on your needs)
  1721 
  1722   constants
  1723      _ $ _        ~> _ $$ _
  1724      \<chi> x. _  ~> \<chi>\<chi> x. _
  1725      CARD('n)     ~> DIM('a)
  1726 
  1727 Also note that the indices are now natural numbers and not from some
  1728 finite type. Finite cartesian products of euclidean spaces, products
  1729 of euclidean spaces the real and complex numbers are instantiated to
  1730 be euclidean_spaces.  INCOMPATIBILITY.
  1731 
  1732 * Session Probability: introduced pextreal as positive extended real
  1733 numbers.  Use pextreal as value for measures.  Introduce the
  1734 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1735 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1736 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1737 
  1738 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1739 INCOMPATIBILITY.
  1740 
  1741 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1742 prove verification conditions generated by the SPARK Ada program
  1743 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1744 
  1745 
  1746 *** HOL-Algebra ***
  1747 
  1748 * Theorems for additive ring operations (locale abelian_monoid and
  1749 descendants) are generated by interpretation from their multiplicative
  1750 counterparts.  Names (in particular theorem names) have the mandatory
  1751 qualifier 'add'.  Previous theorem names are redeclared for
  1752 compatibility.
  1753 
  1754 * Structure "int_ring" is now an abbreviation (previously a
  1755 definition).  This fits more natural with advanced interpretations.
  1756 
  1757 
  1758 *** HOLCF ***
  1759 
  1760 * The domain package now runs in definitional mode by default: The
  1761 former command 'new_domain' is now called 'domain'.  To use the domain
  1762 package in its original axiomatic mode, use 'domain (unsafe)'.
  1763 INCOMPATIBILITY.
  1764 
  1765 * The new class "domain" is now the default sort.  Class "predomain"
  1766 is an unpointed version of "domain". Theories can be updated by
  1767 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1768 
  1769   'a::type ~> 'a::countable
  1770   'a::cpo  ~> 'a::predomain
  1771   'a::pcpo ~> 'a::domain
  1772 
  1773 * The old type class "rep" has been superseded by class "domain".
  1774 Accordingly, users of the definitional package must remove any
  1775 "default_sort rep" declarations.  INCOMPATIBILITY.
  1776 
  1777 * The domain package (definitional mode) now supports unpointed
  1778 predomain argument types, as long as they are marked 'lazy'. (Strict
  1779 arguments must be in class "domain".) For example, the following
  1780 domain definition now works:
  1781 
  1782   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1783 
  1784 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1785 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1786 'a option, and 'a list.  Additionally, it configures fixrec and the
  1787 domain package to work with these types.  For example:
  1788 
  1789   fixrec isInl :: "('a + 'b) u -> tr"
  1790     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1791 
  1792   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1793 
  1794 * The "(permissive)" option of fixrec has been replaced with a
  1795 per-equation "(unchecked)" option. See
  1796 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1797 
  1798 * The "bifinite" class no longer fixes a constant "approx"; the class
  1799 now just asserts that such a function exists.  INCOMPATIBILITY.
  1800 
  1801 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1802 defines an embedding of type 'a defl into udom by default; instances
  1803 of "bifinite" and "domain" classes are available in
  1804 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1805 
  1806 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1807 
  1808 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1809 
  1810 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1811 
  1812 * The function "cprod_map" has been renamed to "prod_map".
  1813 INCOMPATIBILITY.
  1814 
  1815 * The monadic bind operator on each powerdomain has new binder syntax
  1816 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1817 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1818 
  1819 * The infix syntax for binary union on each powerdomain has changed
  1820 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1821 syntax.  INCOMPATIBILITY.
  1822 
  1823 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1824 still supported as an input translation.
  1825 
  1826 * Renamed some theorems (the original names are also still available).
  1827 
  1828   expand_fun_below   ~> fun_below_iff
  1829   below_fun_ext      ~> fun_belowI
  1830   expand_cfun_eq     ~> cfun_eq_iff
  1831   ext_cfun           ~> cfun_eqI
  1832   expand_cfun_below  ~> cfun_below_iff
  1833   below_cfun_ext     ~> cfun_belowI
  1834   cont2cont_Rep_CFun ~> cont2cont_APP
  1835 
  1836 * The Abs and Rep functions for various types have changed names.
  1837 Related theorem names have also changed to match. INCOMPATIBILITY.
  1838 
  1839   Rep_CFun  ~> Rep_cfun
  1840   Abs_CFun  ~> Abs_cfun
  1841   Rep_Sprod ~> Rep_sprod
  1842   Abs_Sprod ~> Abs_sprod
  1843   Rep_Ssum  ~> Rep_ssum
  1844   Abs_Ssum  ~> Abs_ssum
  1845 
  1846 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1847 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1848 
  1849 * Various changes to bisimulation/coinduction with domain package:
  1850 
  1851   - Definitions of "bisim" constants no longer mention definedness.
  1852   - With mutual recursion, "bisim" predicate is now curried.
  1853   - With mutual recursion, each type gets a separate coind theorem.
  1854   - Variable names in bisim_def and coinduct rules have changed.
  1855 
  1856 INCOMPATIBILITY.
  1857 
  1858 * Case combinators generated by the domain package for type "foo" are
  1859 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1860 
  1861 * Several theorems have been renamed to more accurately reflect the
  1862 names of constants and types involved.  INCOMPATIBILITY.
  1863 
  1864   thelub_const    ~> lub_const
  1865   lub_const       ~> is_lub_const
  1866   thelubI         ~> lub_eqI
  1867   is_lub_lub      ~> is_lubD2
  1868   lubI            ~> is_lub_lub
  1869   unique_lub      ~> is_lub_unique
  1870   is_ub_lub       ~> is_lub_rangeD1
  1871   lub_bin_chain   ~> is_lub_bin_chain
  1872   lub_fun         ~> is_lub_fun
  1873   thelub_fun      ~> lub_fun
  1874   thelub_cfun     ~> lub_cfun
  1875   thelub_Pair     ~> lub_Pair
  1876   lub_cprod       ~> is_lub_prod
  1877   thelub_cprod    ~> lub_prod
  1878   minimal_cprod   ~> minimal_prod
  1879   inst_cprod_pcpo ~> inst_prod_pcpo
  1880   UU_I            ~> bottomI
  1881   compact_UU      ~> compact_bottom
  1882   deflation_UU    ~> deflation_bottom
  1883   finite_deflation_UU ~> finite_deflation_bottom
  1884 
  1885 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1886 
  1887   sq_ord_less_eq_trans ~> below_eq_trans
  1888   sq_ord_eq_less_trans ~> eq_below_trans
  1889   refl_less            ~> below_refl
  1890   trans_less           ~> below_trans
  1891   antisym_less         ~> below_antisym
  1892   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1893   box_less             ~> box_below
  1894   rev_trans_less       ~> rev_below_trans
  1895   not_less2not_eq      ~> not_below2not_eq
  1896   less_UU_iff          ~> below_UU_iff
  1897   flat_less_iff        ~> flat_below_iff
  1898   adm_less             ~> adm_below
  1899   adm_not_less         ~> adm_not_below
  1900   adm_compact_not_less ~> adm_compact_not_below
  1901   less_fun_def         ~> below_fun_def
  1902   expand_fun_less      ~> fun_below_iff
  1903   less_fun_ext         ~> fun_belowI
  1904   less_discr_def       ~> below_discr_def
  1905   discr_less_eq        ~> discr_below_eq
  1906   less_unit_def        ~> below_unit_def
  1907   less_cprod_def       ~> below_prod_def
  1908   prod_lessI           ~> prod_belowI
  1909   Pair_less_iff        ~> Pair_below_iff
  1910   fst_less_iff         ~> fst_below_iff
  1911   snd_less_iff         ~> snd_below_iff
  1912   expand_cfun_less     ~> cfun_below_iff
  1913   less_cfun_ext        ~> cfun_belowI
  1914   injection_less       ~> injection_below
  1915   less_up_def          ~> below_up_def
  1916   not_Iup_less         ~> not_Iup_below
  1917   Iup_less             ~> Iup_below
  1918   up_less              ~> up_below
  1919   Def_inject_less_eq   ~> Def_below_Def
  1920   Def_less_is_eq       ~> Def_below_iff
  1921   spair_less_iff       ~> spair_below_iff
  1922   less_sprod           ~> below_sprod
  1923   spair_less           ~> spair_below
  1924   sfst_less_iff        ~> sfst_below_iff
  1925   ssnd_less_iff        ~> ssnd_below_iff
  1926   fix_least_less       ~> fix_least_below
  1927   dist_less_one        ~> dist_below_one
  1928   less_ONE             ~> below_ONE
  1929   ONE_less_iff         ~> ONE_below_iff
  1930   less_sinlD           ~> below_sinlD
  1931   less_sinrD           ~> below_sinrD
  1932 
  1933 
  1934 *** FOL and ZF ***
  1935 
  1936 * All constant names are now qualified internally and use proper
  1937 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1938 
  1939 *** ZF ***
  1940 
  1941 * Greater support for structured proofs involving induction or case analysis.
  1942 
  1943 * Much greater use of special symbols.
  1944 
  1945 * Removal of many ML theorem bindings. INCOMPATIBILITY.
  1946 
  1947 *** ML ***
  1948 
  1949 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1950 Fail if the argument is false.  Due to inlining the source position of
  1951 failed assertions is included in the error output.
  1952 
  1953 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1954 text is in practice always evaluated with a stable theory checkpoint.
  1955 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1956 
  1957 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1958 the current context, not any accidental theory loader state as before.
  1959 Potential INCOMPATIBILITY, subtle change in semantics.
  1960 
  1961 * Syntax.pretty_priority (default 0) configures the required priority
  1962 of pretty-printed output and thus affects insertion of parentheses.
  1963 
  1964 * Syntax.default_root (default "any") configures the inner syntax
  1965 category (nonterminal symbol) for parsing of terms.
  1966 
  1967 * Former exception Library.UnequalLengths now coincides with
  1968 ListPair.UnequalLengths.
  1969 
  1970 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1971 main functionality is provided by structure Simplifier.
  1972 
  1973 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1974 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1975 almost all situations.
  1976 
  1977 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1978 See implementation manual for further details on exceptions in
  1979 Isabelle/ML.
  1980 
  1981 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1982 meaning.
  1983 
  1984 * Renamed structure PureThy to Pure_Thy and moved most of its
  1985 operations to structure Global_Theory, to emphasize that this is
  1986 rarely-used global-only stuff.
  1987 
  1988 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1989 instead (or tracing for high-volume output).
  1990 
  1991 * Configuration option show_question_marks only affects regular pretty
  1992 printing of types and terms, not raw Term.string_of_vname.
  1993 
  1994 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1995 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1996 @{thms} for most purposes.
  1997 
  1998 * ML structure Unsynchronized is never opened, not even in Isar
  1999 interaction mode as before.  Old Unsynchronized.set etc. have been
  2000 discontinued -- use plain := instead.  This should be *rare* anyway,
  2001 since modern tools always work via official context data, notably
  2002 configuration options.
  2003 
  2004 * Parallel and asynchronous execution requires special care concerning
  2005 interrupts.  Structure Exn provides some convenience functions that
  2006 avoid working directly with raw Interrupt.  User code must not absorb
  2007 interrupts -- intermediate handling (for cleanup etc.) needs to be
  2008 followed by re-raising of the original exception.  Another common
  2009 source of mistakes are "handle _" patterns, which make the meaning of
  2010 the program subject to physical effects of the environment.
  2011 
  2012 
  2013 
  2014 New in Isabelle2009-2 (June 2010)
  2015 ---------------------------------
  2016 
  2017 *** General ***
  2018 
  2019 * Authentic syntax for *all* logical entities (type classes, type
  2020 constructors, term constants): provides simple and robust
  2021 correspondence between formal entities and concrete syntax.  Within
  2022 the parse tree / AST representations, "constants" are decorated by
  2023 their category (class, type, const) and spelled out explicitly with
  2024 their full internal name.
  2025 
  2026 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  2027 and translations (translation rules and translation functions in ML).
  2028 Some hints on upgrading:
  2029 
  2030   - Many existing uses of 'syntax' and 'translations' can be replaced
  2031     by more modern 'type_notation', 'notation' and 'abbreviation',
  2032     which are independent of this issue.
  2033 
  2034   - 'translations' require markup within the AST; the term syntax
  2035     provides the following special forms:
  2036 
  2037       CONST c   -- produces syntax version of constant c from context
  2038       XCONST c  -- literally c, checked as constant from context
  2039       c         -- literally c, if declared by 'syntax'
  2040 
  2041     Plain identifiers are treated as AST variables -- occasionally the
  2042     system indicates accidental variables via the error "rhs contains
  2043     extra variables".
  2044 
  2045     Type classes and type constructors are marked according to their
  2046     concrete syntax.  Some old translations rules need to be written
  2047     for the "type" category, using type constructor application
  2048     instead of pseudo-term application of the default category
  2049     "logic".
  2050 
  2051   - 'parse_translation' etc. in ML may use the following
  2052     antiquotations:
  2053 
  2054       @{class_syntax c}   -- type class c within parse tree / AST
  2055       @{term_syntax c}    -- type constructor c within parse tree / AST
  2056       @{const_syntax c}   -- ML version of "CONST c" above
  2057       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  2058 
  2059   - Literal types within 'typed_print_translations', i.e. those *not*
  2060     represented as pseudo-terms are represented verbatim.  Use @{class
  2061     c} or @{type_name c} here instead of the above syntax
  2062     antiquotations.
  2063 
  2064 Note that old non-authentic syntax was based on unqualified base
  2065 names, so all of the above "constant" names would coincide.  Recall
  2066 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  2067 diagnose syntax problems.
  2068 
  2069 * Type constructors admit general mixfix syntax, not just infix.
  2070 
  2071 * Concrete syntax may be attached to local entities without a proof
  2072 body, too.  This works via regular mixfix annotations for 'fix',
  2073 'def', 'obtain' etc. or via the explicit 'write' command, which is
  2074 similar to the 'notation' command in theory specifications.
  2075 
  2076 * Discontinued unnamed infix syntax (legacy feature for many years) --
  2077 need to specify constant name and syntax separately.  Internal ML
  2078 datatype constructors have been renamed from InfixName to Infix etc.
  2079 Minor INCOMPATIBILITY.
  2080 
  2081 * Schematic theorem statements need to be explicitly markup as such,
  2082 via commands 'schematic_lemma', 'schematic_theorem',
  2083 'schematic_corollary'.  Thus the relevance of the proof is made
  2084 syntactically clear, which impacts performance in a parallel or
  2085 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  2086 
  2087 * Use of cumulative prems via "!" in some proof methods has been
  2088 discontinued (old legacy feature).
  2089 
  2090 * References 'trace_simp' and 'debug_simp' have been replaced by
  2091 configuration options stored in the context. Enabling tracing (the
  2092 case of debugging is similar) in proofs works via
  2093 
  2094   using [[trace_simp = true]]
  2095 
  2096 Tracing is then active for all invocations of the simplifier in
  2097 subsequent goal refinement steps. Tracing may also still be enabled or
  2098 disabled via the ProofGeneral settings menu.
  2099 
  2100 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  2101 'hide_fact' replace the former 'hide' KIND command.  Minor
  2102 INCOMPATIBILITY.
  2103 
  2104 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  2105 more efficient than combinations with -q1 or -q2.
  2106 
  2107 
  2108 *** Pure ***
  2109 
  2110 * Proofterms record type-class reasoning explicitly, using the
  2111 "unconstrain" operation internally.  This eliminates all sort
  2112 constraints from a theorem and proof, introducing explicit
  2113 OFCLASS-premises.  On the proof term level, this operation is
  2114 automatically applied at theorem boundaries, such that closed proofs
  2115 are always free of sort constraints.  INCOMPATIBILITY for tools that
  2116 inspect proof terms.
  2117 
  2118 * Local theory specifications may depend on extra type variables that
  2119 are not present in the result type -- arguments TYPE('a) :: 'a itself
  2120 are added internally.  For example:
  2121 
  2122   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  2123 
  2124 * Predicates of locales introduced by classes carry a mandatory
  2125 "class" prefix.  INCOMPATIBILITY.
  2126 
  2127 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  2128 
  2129 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  2130 'class' instead.
  2131 
  2132 * Command 'code_reflect' allows to incorporate generated ML code into
  2133 runtime environment; replaces immature code_datatype antiquotation.
  2134 INCOMPATIBILITY.
  2135 
  2136 * Code generator: simple concept for abstract datatypes obeying
  2137 invariants.
  2138 
  2139 * Code generator: details of internal data cache have no impact on the
  2140 user space functionality any longer.
  2141 
  2142 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  2143 subgoals.  This is more appropriate for interpretations with 'where'.
  2144 INCOMPATIBILITY.
  2145 
  2146 * Command 'example_proof' opens an empty proof body.  This allows to
  2147 experiment with Isar, without producing any persistent result.
  2148 
  2149 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  2150 within a local theory context, with explicit checking of the
  2151 constructors involved (in contrast to the raw 'syntax' versions).
  2152 
  2153 * Commands 'types' and 'typedecl' now work within a local theory
  2154 context -- without introducing dependencies on parameters or
  2155 assumptions, which is not possible in Isabelle/Pure.
  2156 
  2157 * Command 'defaultsort' has been renamed to 'default_sort', it works
  2158 within a local theory context.  Minor INCOMPATIBILITY.
  2159 
  2160 
  2161 *** HOL ***
  2162 
  2163 * Command 'typedef' now works within a local theory context -- without
  2164 introducing dependencies on parameters or assumptions, which is not
  2165 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  2166 contain multiple interpretations of local typedefs (with different
  2167 non-emptiness proofs), even in a global theory context.
  2168 
  2169 * New package for quotient types.  Commands 'quotient_type' and
  2170 'quotient_definition' may be used for defining types and constants by
  2171 quotient constructions.  An example is the type of integers created by
  2172 quotienting pairs of natural numbers:
  2173 
  2174   fun
  2175     intrel :: "(nat * nat) => (nat * nat) => bool"
  2176   where
  2177     "intrel (x, y) (u, v) = (x + v = u + y)"
  2178 
  2179   quotient_type int = "nat * nat" / intrel
  2180     by (auto simp add: equivp_def expand_fun_eq)
  2181 
  2182   quotient_definition
  2183     "0::int" is "(0::nat, 0::nat)"
  2184 
  2185 The method "lifting" can be used to lift of theorems from the
  2186 underlying "raw" type to the quotient type.  The example
  2187 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  2188 construction and provides a reasoning infrastructure for finite sets.
  2189 
  2190 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  2191 clash with new theory Quotient in Main HOL.
  2192 
  2193 * Moved the SMT binding into the main HOL session, eliminating
  2194 separate HOL-SMT session.
  2195 
  2196 * List membership infix mem operation is only an input abbreviation.
  2197 INCOMPATIBILITY.
  2198 
  2199 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  2200 for future developements; former Library/Word.thy is still present in
  2201 the AFP entry RSAPPS.
  2202 
  2203 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  2204 longer shadowed.  INCOMPATIBILITY.
  2205 
  2206 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  2207 INCOMPATIBILITY.
  2208 
  2209 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  2210 INCOMPATIBILITY.
  2211 
  2212 * Dropped normalizing_semiring etc; use the facts in semiring classes
  2213 instead.  INCOMPATIBILITY.
  2214 
  2215 * Dropped several real-specific versions of lemmas about floor and
  2216 ceiling; use the generic lemmas from theory "Archimedean_Field"
  2217 instead.  INCOMPATIBILITY.
  2218 
  2219   floor_number_of_eq         ~> floor_number_of
  2220   le_floor_eq_number_of      ~> number_of_le_floor
  2221   le_floor_eq_zero           ~> zero_le_floor
  2222   le_floor_eq_one            ~> one_le_floor
  2223   floor_less_eq_number_of    ~> floor_less_number_of
  2224   floor_less_eq_zero         ~> floor_less_zero
  2225   floor_less_eq_one          ~> floor_less_one
  2226   less_floor_eq_number_of    ~> number_of_less_floor
  2227   less_floor_eq_zero         ~> zero_less_floor
  2228   less_floor_eq_one          ~> one_less_floor
  2229   floor_le_eq_number_of      ~> floor_le_number_of
  2230   floor_le_eq_zero           ~> floor_le_zero
  2231   floor_le_eq_one            ~> floor_le_one
  2232   floor_subtract_number_of   ~> floor_diff_number_of
  2233   floor_subtract_one         ~> floor_diff_one
  2234   ceiling_number_of_eq       ~> ceiling_number_of
  2235   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  2236   ceiling_le_zero_eq         ~> ceiling_le_zero
  2237   ceiling_le_eq_one          ~> ceiling_le_one
  2238   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  2239   less_ceiling_eq_zero       ~> zero_less_ceiling
  2240   less_ceiling_eq_one        ~> one_less_ceiling
  2241   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  2242   ceiling_less_eq_zero       ~> ceiling_less_zero
  2243   ceiling_less_eq_one        ~> ceiling_less_one
  2244   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  2245   le_ceiling_eq_zero         ~> zero_le_ceiling
  2246   le_ceiling_eq_one          ~> one_le_ceiling
  2247   ceiling_subtract_number_of ~> ceiling_diff_number_of
  2248   ceiling_subtract_one       ~> ceiling_diff_one
  2249 
  2250 * Theory "Finite_Set": various folding_XXX locales facilitate the
  2251 application of the various fold combinators on finite sets.
  2252 
  2253 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  2254 provides abstract red-black tree type which is backed by "RBT_Impl" as
  2255 implementation.  INCOMPATIBILTY.
  2256 
  2257 * Theory Library/Coinductive_List has been removed -- superseded by
  2258 AFP/thys/Coinductive.
  2259 
  2260 * Theory PReal, including the type "preal" and related operations, has
  2261 been removed.  INCOMPATIBILITY.
  2262 
  2263 * Real: new development using Cauchy Sequences.
  2264 
  2265 * Split off theory "Big_Operators" containing setsum, setprod,
  2266 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  2267 
  2268 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  2269 "Int" etc.  INCOMPATIBILITY.
  2270 
  2271 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  2272 
  2273 * New set of rules "ac_simps" provides combined assoc / commute
  2274 rewrites for all interpretations of the appropriate generic locales.
  2275 
  2276 * Renamed theory "OrderedGroup" to "Groups" and split theory
  2277 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  2278 appropriate and more consistent names suitable for name prefixes
  2279 within the HOL theories.  INCOMPATIBILITY.
  2280 
  2281 * Some generic constants have been put to appropriate theories:
  2282   - less_eq, less: Orderings
  2283   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  2284   - inverse, divide: Rings
  2285 INCOMPATIBILITY.
  2286 
  2287 * More consistent naming of type classes involving orderings (and
  2288 lattices):
  2289 
  2290     lower_semilattice                   ~> semilattice_inf
  2291     upper_semilattice                   ~> semilattice_sup
  2292 
  2293     dense_linear_order                  ~> dense_linorder
  2294 
  2295     pordered_ab_group_add               ~> ordered_ab_group_add
  2296     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  2297     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  2298     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  2299     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  2300     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  2301     pordered_cancel_semiring            ~> ordered_cancel_semiring
  2302     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  2303     pordered_comm_ring                  ~> ordered_comm_ring
  2304     pordered_comm_semiring              ~> ordered_comm_semiring
  2305     pordered_ring                       ~> ordered_ring
  2306     pordered_ring_abs                   ~> ordered_ring_abs
  2307     pordered_semiring                   ~> ordered_semiring
  2308 
  2309     ordered_ab_group_add                ~> linordered_ab_group_add
  2310     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  2311     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  2312     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  2313     ordered_field                       ~> linordered_field
  2314     ordered_field_no_lb                 ~> linordered_field_no_lb
  2315     ordered_field_no_ub                 ~> linordered_field_no_ub
  2316     ordered_field_dense_linear_order    ~> dense_linordered_field
  2317     ordered_idom                        ~> linordered_idom
  2318     ordered_ring                        ~> linordered_ring
  2319     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  2320     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  2321     ordered_ring_strict                 ~> linordered_ring_strict
  2322     ordered_semidom                     ~> linordered_semidom
  2323     ordered_semiring                    ~> linordered_semiring
  2324     ordered_semiring_1                  ~> linordered_semiring_1
  2325     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  2326     ordered_semiring_strict             ~> linordered_semiring_strict
  2327 
  2328   The following slightly odd type classes have been moved to a
  2329   separate theory Library/Lattice_Algebras:
  2330 
  2331     lordered_ab_group_add               ~> lattice_ab_group_add
  2332     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  2333     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  2334     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  2335     lordered_ring                       ~> lattice_ring
  2336 
  2337 INCOMPATIBILITY.
  2338 
  2339 * Refined field classes:
  2340   - classes division_ring_inverse_zero, field_inverse_zero,
  2341     linordered_field_inverse_zero include rule inverse 0 = 0 --
  2342     subsumes former division_by_zero class;
  2343   - numerous lemmas have been ported from field to division_ring.
  2344 INCOMPATIBILITY.
  2345 
  2346 * Refined algebra theorem collections:
  2347   - dropped theorem group group_simps, use algebra_simps instead;
  2348   - dropped theorem group ring_simps, use field_simps instead;
  2349   - proper theorem collection field_simps subsumes former theorem
  2350     groups field_eq_simps and field_simps;
  2351   - dropped lemma eq_minus_self_iff which is a duplicate for
  2352     equal_neg_zero.
  2353 INCOMPATIBILITY.
  2354 
  2355 * Theory Finite_Set and List: some lemmas have been generalized from
  2356 sets to lattices:
  2357 
  2358   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  2359   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  2360   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  2361   union_Union_fold_union        ~> sup_Sup_fold_sup
  2362   Inter_fold_inter              ~> Inf_fold_inf
  2363   Union_fold_union              ~> Sup_fold_sup
  2364   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  2365   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  2366   INTER_fold_inter              ~> INFI_fold_inf
  2367   UNION_fold_union              ~> SUPR_fold_sup
  2368 
  2369 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  2370 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  2371 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  2372 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  2373 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  2374 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  2375 
  2376 * Reorganized theory Multiset: swapped notation of pointwise and
  2377 multiset order:
  2378 
  2379   - pointwise ordering is instance of class order with standard syntax
  2380     <= and <;
  2381   - multiset ordering has syntax <=# and <#; partial order properties
  2382     are provided by means of interpretation with prefix
  2383     multiset_order;
  2384   - less duplication, less historical organization of sections,
  2385     conversion from associations lists to multisets, rudimentary code
  2386     generation;
  2387   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  2388     if needed.
  2389 
  2390 Renamed:
  2391 
  2392   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  2393   multi_count_ext  ~>  multiset_ext
  2394   diff_union_inverse2  ~>  diff_union_cancelR
  2395 
  2396 INCOMPATIBILITY.
  2397 
  2398 * Theory Permutation: replaced local "remove" by List.remove1.
  2399 
  2400 * Code generation: ML and OCaml code is decorated with signatures.
  2401 
  2402 * Theory List: added transpose.
  2403 
  2404 * Library/Nat_Bijection.thy is a collection of bijective functions
  2405 between nat and other types, which supersedes the older libraries
  2406 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2407 
  2408   Constants:
  2409   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2410   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2411   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2412   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2413   Countable.pair_encode           ~> prod_encode
  2414   NatIso.prod2nat                 ~> prod_encode
  2415   NatIso.nat2prod                 ~> prod_decode
  2416   NatIso.sum2nat                  ~> sum_encode
  2417   NatIso.nat2sum                  ~> sum_decode
  2418   NatIso.list2nat                 ~> list_encode
  2419   NatIso.nat2list                 ~> list_decode
  2420   NatIso.set2nat                  ~> set_encode
  2421   NatIso.nat2set                  ~> set_decode
  2422 
  2423   Lemmas:
  2424   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2425   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2426   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2427   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2428   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2429   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2430   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2431   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2432   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2433   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2434   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2435   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2436   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2437 
  2438 * Sledgehammer:
  2439   - Renamed ATP commands:
  2440     atp_info     ~> sledgehammer running_atps
  2441     atp_kill     ~> sledgehammer kill_atps
  2442     atp_messages ~> sledgehammer messages
  2443     atp_minimize ~> sledgehammer minimize
  2444     print_atps   ~> sledgehammer available_atps
  2445     INCOMPATIBILITY.
  2446   - Added user's manual ("isabelle doc sledgehammer").
  2447   - Added option syntax and "sledgehammer_params" to customize
  2448     Sledgehammer's behavior.  See the manual for details.
  2449   - Modified the Isar proof reconstruction code so that it produces
  2450     direct proofs rather than proofs by contradiction.  (This feature
  2451     is still experimental.)
  2452   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2453     full-typed mode.
  2454   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2455 
  2456 * Nitpick:
  2457   - Added and implemented "binary_ints" and "bits" options.
  2458   - Added "std" option and implemented support for nonstandard models.
  2459   - Added and implemented "finitize" option to improve the precision
  2460     of infinite datatypes based on a monotonicity analysis.
  2461   - Added support for quotient types.
  2462   - Added support for "specification" and "ax_specification"
  2463     constructs.
  2464   - Added support for local definitions (for "function" and
  2465     "termination" proofs).
  2466   - Added support for term postprocessors.
  2467   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2468   - Improved efficiency of "destroy_constrs" optimization.
  2469   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2470     record getters.
  2471   - Fixed soundness bug related to higher-order constructors.
  2472   - Fixed soundness bug when "full_descrs" is enabled.
  2473   - Improved precision of set constructs.
  2474   - Added "atoms" option.
  2475   - Added cache to speed up repeated Kodkod invocations on the same
  2476     problems.
  2477   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2478     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2479     "SAT4J_Light".  INCOMPATIBILITY.
  2480   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2481     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2482   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2483 
  2484 * Method "induct" now takes instantiations of the form t, where t is not
  2485   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2486   If this is not intended, t has to be enclosed in parentheses.
  2487   By default, the equalities generated by definitional instantiations
  2488   are pre-simplified, which may cause parameters of inductive cases
  2489   to disappear, or may even delete some of the inductive cases.
  2490   Use "induct (no_simp)" instead of "induct" to restore the old
  2491   behaviour. The (no_simp) option is also understood by the "cases"
  2492   and "nominal_induct" methods, which now perform pre-simplification, too.
  2493   INCOMPATIBILITY.
  2494 
  2495 
  2496 *** HOLCF ***
  2497 
  2498 * Variable names in lemmas generated by the domain package have
  2499 changed; the naming scheme is now consistent with the HOL datatype
  2500 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2501 
  2502 * The domain package no longer defines the function "foo_copy" for
  2503 recursive domain "foo".  The reach lemma is now stated directly in
  2504 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2505 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2506 
  2507 * Most definedness lemmas generated by the domain package (previously
  2508 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2509 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2510 Proofs that used definedness lemmas as intro rules may break,
  2511 potential INCOMPATIBILITY.
  2512 
  2513 * Induction and casedist rules generated by the domain package now
  2514 declare proper case_names (one called "bottom", and one named for each
  2515 constructor).  INCOMPATIBILITY.
  2516 
  2517 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2518 rules are generated for each domain, INCOMPATIBILITY.
  2519 
  2520   foo_bar.reach       ~> foo.reach  bar.reach
  2521   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2522 
  2523 * Some lemmas generated by the domain package have been renamed for
  2524 consistency with the datatype package, INCOMPATIBILITY.
  2525 
  2526   foo.ind        ~> foo.induct
  2527   foo.finite_ind ~> foo.finite_induct
  2528   foo.coind      ~> foo.coinduct
  2529   foo.casedist   ~> foo.exhaust
  2530   foo.exhaust    ~> foo.nchotomy
  2531 
  2532 * For consistency with other definition packages, the fixrec package
  2533 now generates qualified theorem names, INCOMPATIBILITY.
  2534 
  2535   foo_simps  ~> foo.simps
  2536   foo_unfold ~> foo.unfold
  2537   foo_induct ~> foo.induct
  2538 
  2539 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2540 method and internal fixrec proofs now use the default simpset instead.
  2541 INCOMPATIBILITY.
  2542 
  2543 * The "contlub" predicate has been removed.  Proof scripts should use
  2544 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2545 
  2546 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2547 
  2548 * The constants cpair, cfst, and csnd have been removed in favor of
  2549 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2550 
  2551 
  2552 *** ML ***
  2553 
  2554 * Antiquotations for basic formal entities:
  2555 
  2556     @{class NAME}         -- type class
  2557     @{class_syntax NAME}  -- syntax representation of the above
  2558 
  2559     @{type_name NAME}     -- logical type
  2560     @{type_abbrev NAME}   -- type abbreviation
  2561     @{nonterminal NAME}   -- type of concrete syntactic category
  2562     @{type_syntax NAME}   -- syntax representation of any of the above
  2563 
  2564     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2565     @{const_abbrev NAME}  -- abbreviated constant
  2566     @{const_syntax NAME}  -- syntax representation of any of the above
  2567 
  2568 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2569 syntax constant (cf. 'syntax' command).
  2570 
  2571 * Antiquotation @{make_string} inlines a function to print arbitrary
  2572 values similar to the ML toplevel.  The result is compiler dependent
  2573 and may fall back on "?" in certain situations.
  2574 
  2575 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2576 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2577 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2578 not work with the asynchronous Isar document model.
  2579 
  2580 * Configuration options now admit dynamic default values, depending on
  2581 the context or even global references.
  2582 
  2583 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2584 uses an efficient external library if available (for Poly/ML).
  2585 
  2586 * Renamed some important ML structures, while keeping the old names
  2587 for some time as aliases within the structure Legacy:
  2588 
  2589   OuterKeyword  ~>  Keyword
  2590   OuterLex      ~>  Token
  2591   OuterParse    ~>  Parse
  2592   OuterSyntax   ~>  Outer_Syntax
  2593   PrintMode     ~>  Print_Mode
  2594   SpecParse     ~>  Parse_Spec
  2595   ThyInfo       ~>  Thy_Info
  2596   ThyLoad       ~>  Thy_Load
  2597   ThyOutput     ~>  Thy_Output
  2598   TypeInfer     ~>  Type_Infer
  2599 
  2600 Note that "open Legacy" simplifies porting of sources, but forgetting
  2601 to remove it again will complicate porting again in the future.
  2602 
  2603 * Most operations that refer to a global context are named
  2604 accordingly, e.g. Simplifier.global_context or
  2605 ProofContext.init_global.  There are some situations where a global
  2606 context actually works, but under normal circumstances one needs to
  2607 pass the proper local context through the code!
  2608 
  2609 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2610 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2611 Pretty.pp argument to merge, which is absent in the standard
  2612 Theory_Data version.
  2613 
  2614 * Sorts.certify_sort and derived "cert" operations for types and terms
  2615 no longer minimize sorts.  Thus certification at the boundary of the
  2616 inference kernel becomes invariant under addition of class relations,
  2617 which is an important monotonicity principle.  Sorts are now minimized
  2618 in the syntax layer only, at the boundary between the end-user and the
  2619 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2620 explicitly in rare situations.
  2621 
  2622 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2623 emphasize that this is in no way a standard operation.
  2624 INCOMPATIBILITY.
  2625 
  2626 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2627 usual for resolution.  Rare INCOMPATIBILITY.
  2628 
  2629 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2630 to emphasize that these only work in a global situation (which is
  2631 quite rare).
  2632 
  2633 * Curried take and drop in library.ML; negative length is interpreted
  2634 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2635 
  2636 * Proof terms: type substitutions on proof constants now use canonical
  2637 order of type variables.  INCOMPATIBILITY for tools working with proof
  2638 terms.
  2639 
  2640 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2641 may no longer carry premises.  User-level specifications are
  2642 transformed accordingly by Thm.add_axiom/add_def.
  2643 
  2644 
  2645 *** System ***
  2646 
  2647 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2648 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2649 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2650 
  2651 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2652 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2653 respectively.
  2654 
  2655 * Old lib/scripts/polyml-platform is superseded by the
  2656 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2657 variant, even on a 64 bit machine.  The following example setting
  2658 prefers 64 bit if available:
  2659 
  2660   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2661 
  2662 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2663 Isabelle/Scala layer for advanced prover interaction and integration.
  2664 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2665 component.
  2666 
  2667 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2668 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2669 similar to the default assignment of the document preparation system
  2670 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2671 provides some operations for direct access to the font without asking
  2672 the user for manual installation.
  2673 
  2674 
  2675 
  2676 New in Isabelle2009-1 (December 2009)
  2677 -------------------------------------
  2678 
  2679 *** General ***
  2680 
  2681 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2682 one backslash should be used, even in ML sources.
  2683 
  2684 
  2685 *** Pure ***
  2686 
  2687 * Locale interpretation propagates mixins along the locale hierarchy.
  2688 The currently only available mixins are the equations used to map
  2689 local definitions to terms of the target domain of an interpretation.
  2690 
  2691 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2692 loc" to print all interpretations of locale "loc" in the theory.
  2693 Interpretations in proofs are not shown.
  2694 
  2695 * Thoroughly revised locales tutorial.  New section on conditional
  2696 interpretation.
  2697 
  2698 * On instantiation of classes, remaining undefined class parameters
  2699 are formally declared.  INCOMPATIBILITY.
  2700 
  2701 
  2702 *** Document preparation ***
  2703 
  2704 * New generalized style concept for printing terms: @{foo (style) ...}
  2705 instead of @{foo_style style ...}  (old form is still retained for
  2706 backward compatibility).  Styles can be also applied for
  2707 antiquotations prop, term_type and typeof.
  2708 
  2709 
  2710 *** HOL ***
  2711 
  2712 * New proof method "smt" for a combination of first-order logic with
  2713 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2714 fixed-size bitvectors; there is also basic support for higher-order
  2715 features (esp. lambda abstractions).  It is an incomplete decision
  2716 procedure based on external SMT solvers using the oracle mechanism;
  2717 for the SMT solver Z3, this method is proof-producing.  Certificates
  2718 are provided to avoid calling the external solvers solely for
  2719 re-checking proofs.  Due to a remote SMT service there is no need for
  2720 installing SMT solvers locally.  See src/HOL/SMT.
  2721 
  2722 * New commands to load and prove verification conditions generated by
  2723 the Boogie program verifier or derived systems (e.g. the Verifying C
  2724 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2725 
  2726 * New counterexample generator tool 'nitpick' based on the Kodkod
  2727 relational model finder.  See src/HOL/Tools/Nitpick and
  2728 src/HOL/Nitpick_Examples.
  2729 
  2730 * New commands 'code_pred' and 'values' to invoke the predicate
  2731 compiler and to enumerate values of inductive predicates.
  2732 
  2733 * A tabled implementation of the reflexive transitive closure.
  2734 
  2735 * New implementation of quickcheck uses generic code generator;
  2736 default generators are provided for all suitable HOL types, records
  2737 and datatypes.  Old quickcheck can be re-activated importing theory
  2738 Library/SML_Quickcheck.
  2739 
  2740 * New testing tool Mirabelle for automated proof tools.  Applies
  2741 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2742 every proof step in a theory.  To be used in batch mode via the
  2743 "mirabelle" utility.
  2744 
  2745 * New proof method "sos" (sum of squares) for nonlinear real
  2746 arithmetic (originally due to John Harison). It requires theory
  2747 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2748 works well in practice on quantifier-free real arithmetic with +, -,
  2749 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2750 inequalities between polynomials.  It makes use of external
  2751 semidefinite programming solvers.  Method "sos" generates a
  2752 certificate that can be pasted into the proof thus avoiding the need
  2753 to call an external tool every time the proof is checked.  See
  2754 src/HOL/Library/Sum_Of_Squares.
  2755 
  2756 * New method "linarith" invokes existing linear arithmetic decision
  2757 procedure only.
  2758 
  2759 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2760 
  2761 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2762 Causes full type information to be output to the ATPs.  This slows
  2763 ATPs down considerably but eliminates a source of unsound "proofs"
  2764 that fail later.
  2765 
  2766 * New method "metisFT": A version of metis that uses full type
  2767 information in order to avoid failures of proof reconstruction.
  2768 
  2769 * New evaluator "approximate" approximates an real valued term using
  2770 the same method as the approximation method.
  2771 
  2772 * Method "approximate" now supports arithmetic expressions as
  2773 boundaries of intervals and implements interval splitting and Taylor
  2774 series expansion.
  2775 
  2776 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2777 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2778 
  2779 * New theory SupInf of the supremum and infimum operators for sets of
  2780 reals.
  2781 
  2782 * New theory Probability, which contains a development of measure
  2783 theory, eventually leading to Lebesgue integration and probability.
  2784 
  2785 * Extended Multivariate Analysis to include derivation and Brouwer's
  2786 fixpoint theorem.
  2787 
  2788 * Reorganization of number theory, INCOMPATIBILITY:
  2789   - new number theory development for nat and int, in theories Divides
  2790     and GCD as well as in new session Number_Theory
  2791   - some constants and facts now suffixed with _nat and _int
  2792     accordingly
  2793   - former session NumberTheory now named Old_Number_Theory, including
  2794     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2795   - moved theory Pocklington from src/HOL/Library to
  2796     src/HOL/Old_Number_Theory
  2797 
  2798 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2799 lcm of finite and infinite sets. It is shown that they form a complete
  2800 lattice.
  2801 
  2802 * Class semiring_div requires superclass no_zero_divisors and proof of
  2803 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2804 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2805 generalized to class semiring_div, subsuming former theorems
  2806 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2807 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2808 INCOMPATIBILITY.
  2809 
  2810 * Refinements to lattice classes and sets:
  2811   - less default intro/elim rules in locale variant, more default
  2812     intro/elim rules in class variant: more uniformity
  2813   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2814     le_inf_iff
  2815   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2816     sup_aci)
  2817   - renamed ACI to inf_sup_aci
  2818   - new class "boolean_algebra"
  2819   - class "complete_lattice" moved to separate theory
  2820     "Complete_Lattice"; corresponding constants (and abbreviations)
  2821     renamed and with authentic syntax:
  2822     Set.Inf ~>    Complete_Lattice.Inf
  2823     Set.Sup ~>    Complete_Lattice.Sup
  2824     Set.INFI ~>   Complete_Lattice.INFI
  2825     Set.SUPR ~>   Complete_Lattice.SUPR
  2826     Set.Inter ~>  Complete_Lattice.Inter
  2827     Set.Union ~>  Complete_Lattice.Union
  2828     Set.INTER ~>  Complete_Lattice.INTER
  2829     Set.UNION ~>  Complete_Lattice.UNION
  2830   - authentic syntax for
  2831     Set.Pow
  2832     Set.image
  2833   - mere abbreviations:
  2834     Set.empty               (for bot)
  2835     Set.UNIV                (for top)
  2836     Set.inter               (for inf, formerly Set.Int)
  2837     Set.union               (for sup, formerly Set.Un)
  2838     Complete_Lattice.Inter  (for Inf)
  2839     Complete_Lattice.Union  (for Sup)
  2840     Complete_Lattice.INTER  (for INFI)
  2841     Complete_Lattice.UNION  (for SUPR)
  2842   - object-logic definitions as far as appropriate
  2843 
  2844 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2845 Un_subset_iff are explicitly deleted as default simp rules; then also
  2846 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2847 deleted to achieve the desired effect.
  2848 
  2849 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2850 rules by default any longer; the same applies to min_max.inf_absorb1
  2851 etc.  INCOMPATIBILITY.
  2852 
  2853 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2854 pred_set_conv by default.  INCOMPATIBILITY.
  2855 
  2856 * Power operations on relations and functions are now one dedicated
  2857 constant "compow" with infix syntax "^^".  Power operation on
  2858 multiplicative monoids retains syntax "^" and is now defined generic
  2859 in class power.  INCOMPATIBILITY.
  2860 
  2861 * Relation composition "R O S" now has a more standard argument order:
  2862 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2863 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2864 break, since the O_assoc rule was not rewritten like this.  Fix using
  2865 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2866 
  2867 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2868 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2869 INCOMPATIBILITY.
  2870 
  2871 * Most rules produced by inductive and datatype package have mandatory
  2872 prefixes.  INCOMPATIBILITY.
  2873 
  2874 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2875 the attribute of the same name.  Each of the theorems in the list
  2876 DERIV_intros assumes composition with an additional function and
  2877 matches a variable to the derivative, which has to be solved by the
  2878 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2879 of most elementary terms.  Former Maclauren.DERIV_tac and
  2880 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2881 INCOMPATIBILITY.
  2882 
  2883 * Code generator attributes follow the usual underscore convention:
  2884     code_unfold     replaces    code unfold
  2885     code_post       replaces    code post
  2886     etc.
  2887   INCOMPATIBILITY.
  2888 
  2889 * Renamed methods:
  2890     sizechange -> size_change
  2891     induct_scheme -> induction_schema
  2892   INCOMPATIBILITY.
  2893 
  2894 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2895 INCOMPATIBILITY, use "undefined" directly.
  2896 
  2897 * Renamed theorems:
  2898     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2899     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2900     Suc_plus1 -> Suc_eq_plus1
  2901     *anti_sym -> *antisym*
  2902     vector_less_eq_def -> vector_le_def
  2903   INCOMPATIBILITY.
  2904 
  2905 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2906 INCOMPATIBILITY.
  2907 
  2908 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2909 INCOMPATIBILITY.
  2910 
  2911 
  2912 *** HOLCF ***
  2913 
  2914 * Theory Representable defines a class "rep" of domains that are
  2915 representable (via an ep-pair) in the universal domain type "udom".
  2916 Instances are provided for all type constructors defined in HOLCF.
  2917 
  2918 * The 'new_domain' command is a purely definitional version of the
  2919 domain package, for representable domains.  Syntax is identical to the
  2920 old domain package.  The 'new_domain' package also supports indirect
  2921 recursion using previously-defined type constructors.  See
  2922 src/HOLCF/ex/New_Domain.thy for examples.
  2923 
  2924 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2925 on the left-hand side of an equation, and then performs
  2926 simplification.  Rewriting is done using rules declared with the
  2927 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2928 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2929 
  2930 * The pattern-match compiler in 'fixrec' can now handle constructors
  2931 with HOL function types.  Pattern-match combinators for the Pair
  2932 constructor are pre-configured.
  2933 
  2934 * The 'fixrec' package now produces better fixed-point induction rules
  2935 for mutually-recursive definitions:  Induction rules have conclusions
  2936 of the form "P foo bar" instead of "P <foo, bar>".
  2937 
  2938 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2939 been renamed to "below".  The name "below" now replaces "less" in many
  2940 theorem names.  (Legacy theorem names using "less" are still supported
  2941 as well.)
  2942 
  2943 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2944 patterns can be used to generate strictness rules, or to make
  2945 functions more strict (much like the bang-patterns supported by the
  2946 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2947 examples.
  2948 
  2949 
  2950 *** ML ***
  2951 
  2952 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2953 errors and run-time exceptions, including detailed source positions.
  2954 
  2955 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2956 identified entries, with some additional information such as source
  2957 position, logical grouping etc.
  2958 
  2959 * Theory and context data is now introduced by the simplified and
  2960 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2961 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2962 copy operation) is still available for some time.
  2963 
  2964 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2965 provides a high-level programming interface to synchronized state
  2966 variables with atomic update.  This works via pure function
  2967 application within a critical section -- its runtime should be as
  2968 short as possible; beware of deadlocks if critical code is nested,
  2969 either directly or indirectly via other synchronized variables!
  2970 
  2971 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2972 wraps raw ML references, explicitly indicating their non-thread-safe
  2973 behaviour.  The Isar toplevel keeps this structure open, to
  2974 accommodate Proof General as well as quick and dirty interactive
  2975 experiments with references.
  2976 
  2977 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2978 parallel tactical reasoning.
  2979 
  2980 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2981 are similar to SUBPROOF, but are slightly more flexible: only the
  2982 specified parts of the subgoal are imported into the context, and the
  2983 body tactic may introduce new subgoals and schematic variables.
  2984 
  2985 * Old tactical METAHYPS, which does not observe the proof context, has
  2986 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2987 or Subgoal.FOCUS etc.
  2988 
  2989 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2990 functors have their own ML name space there is no point to mark them
  2991 separately.)  Minor INCOMPATIBILITY.
  2992 
  2993 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2994 
  2995 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2996 INCOMPATIBILITY.
  2997 
  2998 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2999 mode, which avoids critical setmp.
  3000 
  3001 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  3002 combinators for "args".  INCOMPATIBILITY, need to use simplified
  3003 Attrib/Method.setup introduced in Isabelle2009.
  3004 
  3005 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  3006 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  3007 last resort.  INCOMPATIBILITY.
  3008 
  3009 * Display.pretty_thm now requires a proper context (cf. former
  3010 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  3011 or even Display.pretty_thm_without_context as last resort.
  3012 INCOMPATIBILITY.
  3013 
  3014 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  3015 Syntax.pretty_typ/term directly, preferably with proper context
  3016 instead of global theory.
  3017 
  3018 
  3019 *** System ***
  3020 
  3021 * Further fine tuning of parallel proof checking, scales up to 8 cores
  3022 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  3023 usedir option -q.
  3024 
  3025 * Support for additional "Isabelle components" via etc/components, see
  3026 also the system manual.
  3027 
  3028 * The isabelle makeall tool now operates on all components with
  3029 IsaMakefile, not just hardwired "logics".
  3030 
  3031 * Removed "compress" option from isabelle-process and isabelle usedir;
  3032 this is always enabled.
  3033 
  3034 * Discontinued support for Poly/ML 4.x versions.
  3035 
  3036 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  3037 on a given logic image.  This requires the lighttpd webserver and is
  3038 currently supported on Linux only.
  3039 
  3040 
  3041 
  3042 New in Isabelle2009 (April 2009)
  3043 --------------------------------
  3044 
  3045 *** General ***
  3046 
  3047 * Simplified main Isabelle executables, with less surprises on
  3048 case-insensitive file-systems (such as Mac OS).
  3049 
  3050   - The main Isabelle tool wrapper is now called "isabelle" instead of
  3051     "isatool."
  3052 
  3053   - The former "isabelle" alias for "isabelle-process" has been
  3054     removed (should rarely occur to regular users).
  3055 
  3056   - The former "isabelle-interface" and its alias "Isabelle" have been
  3057     removed (interfaces are now regular Isabelle tools).
  3058 
  3059 Within scripts and make files, the Isabelle environment variables
  3060 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  3061 respectively.  (The latter are still available as legacy feature.)
  3062 
  3063 The old isabelle-interface wrapper could react in confusing ways if
  3064 the interface was uninstalled or changed otherwise.  Individual
  3065 interface tool configuration is now more explicit, see also the
  3066 Isabelle system manual.  In particular, Proof General is now available
  3067 via "isabelle emacs".
  3068 
  3069 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  3070 purge installed copies of Isabelle executables and re-run "isabelle
  3071 install -p ...", or use symlinks.
  3072 
  3073 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  3074 old ~/isabelle, which was slightly non-standard and apt to cause
  3075 surprises on case-insensitive file-systems (such as Mac OS).
  3076 
  3077 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  3078 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  3079 care is required when using older releases of Isabelle.  Note that
  3080 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  3081 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  3082 
  3083 * Proofs of fully specified statements are run in parallel on
  3084 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  3085 a regular 4-core machine, if the initial heap space is made reasonably
  3086 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  3087 
  3088 * The main reference manuals ("isar-ref", "implementation", and
  3089 "system") have been updated and extended.  Formally checked references
  3090 as hyperlinks are now available uniformly.
  3091 
  3092 
  3093 *** Pure ***
  3094 
  3095 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  3096 respects.  The most important changes are listed below.  See the
  3097 Tutorial on Locales ("locales" manual) for details.
  3098 
  3099 - In locale expressions, instantiation replaces renaming.  Parameters
  3100 must be declared in a for clause.  To aid compatibility with previous
  3101 parameter inheritance, in locale declarations, parameters that are not
  3102 'touched' (instantiation position "_" or omitted) are implicitly added
  3103 with their syntax at the beginning of the for clause.
  3104 
  3105 - Syntax from abbreviations and definitions in locales is available in
  3106 locale expressions and context elements.  The latter is particularly
  3107 useful in locale declarations.
  3108 
  3109 - More flexible mechanisms to qualify names generated by locale
  3110 expressions.  Qualifiers (prefixes) may be specified in locale
  3111 expressions, and can be marked as mandatory (syntax: "name!:") or
  3112 optional (syntax "name?:").  The default depends for plain "name:"
  3113 depends on the situation where a locale expression is used: in
  3114 commands 'locale' and 'sublocale' prefixes are optional, in
  3115 'interpretation' and 'interpret' prefixes are mandatory.  The old
  3116 implicit qualifiers derived from the parameter names of a locale are
  3117 no longer generated.
  3118 
  3119 - Command "sublocale l < e" replaces "interpretation l < e".  The
  3120 instantiation clause in "interpretation" and "interpret" (square
  3121 brackets) is no longer available.  Use locale expressions.
  3122 
  3123 - When converting proof scripts, mandatory qualifiers in
  3124 'interpretation' and 'interpret' should be retained by default, even
  3125 if this is an INCOMPATIBILITY compared to former behavior.  In the
  3126 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  3127 in locale expressions range over a single locale instance only.
  3128 
  3129 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  3130 In existing theorem specifications replace the includes element by the
  3131 respective context elements of the included locale, omitting those
  3132 that are already present in the theorem specification.  Multiple
  3133 assume elements of a locale should be replaced by a single one
  3134 involving the locale predicate.  In the proof body, declarations (most
  3135 notably theorems) may be regained by interpreting the respective
  3136 locales in the proof context as required (command "interpret").
  3137 
  3138 If using "includes" in replacement of a target solely because the
  3139 parameter types in the theorem are not as general as in the target,
  3140 consider declaring a new locale with additional type constraints on
  3141 the parameters (context element "constrains").
  3142 
  3143 - Discontinued "locale (open)".  INCOMPATIBILITY.
  3144 
  3145 - Locale interpretation commands no longer attempt to simplify goal.
  3146 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  3147 methods intro_locales and unfold_locales to clarify.
  3148 
  3149 - Locale interpretation commands no longer accept interpretation
  3150 attributes.  INCOMPATIBILITY.
  3151 
  3152 * Class declaration: so-called "base sort" must not be given in import
  3153 list any longer, but is inferred from the specification.  Particularly
  3154 in HOL, write
  3155 
  3156     class foo = ...
  3157 
  3158 instead of
  3159 
  3160     class foo = type + ...
  3161 
  3162 * Class target: global versions of theorems stemming do not carry a
  3163 parameter prefix any longer.  INCOMPATIBILITY.
  3164 
  3165 * Class 'instance' command no longer accepts attached definitions.
  3166 INCOMPATIBILITY, use proper 'instantiation' target instead.
  3167 
  3168 * Recovered hiding of consts, which was accidentally broken in
  3169 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  3170 makes c inaccessible; consider using ``hide (open) const c'' instead.
  3171 
  3172 * Slightly more coherent Pure syntax, with updated documentation in
  3173 isar-ref manual.  Removed locales meta_term_syntax and
  3174 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  3175 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  3176 directly in regular applications.
  3177 
  3178 * There is a new syntactic category "float_const" for signed decimal
  3179 fractions (e.g. 123.45 or -123.45).
  3180 
  3181 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  3182 interface with 'setup' command instead.
  3183 
  3184 * Command 'local_setup' is similar to 'setup', but operates on a local
  3185 theory context.
  3186 
  3187 * The 'axiomatization' command now only works within a global theory
  3188 context.  INCOMPATIBILITY.
  3189 
  3190 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  3191 hypotheses.  Sorts required in the course of reasoning need to be
  3192 covered by the constraints in the initial statement, completed by the
  3193 type instance information of the background theory.  Non-trivial sort
  3194 hypotheses, which rarely occur in practice, may be specified via
  3195 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  3196 
  3197   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  3198 
  3199 The result contains an implicit sort hypotheses as before --
  3200 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  3201 normalization.
  3202 
  3203 * Generalized Isar history, with support for linear undo, direct state
  3204 addressing etc.
  3205 
  3206 * Changed defaults for unify configuration options:
  3207 
  3208   unify_trace_bound = 50 (formerly 25)
  3209   unify_search_bound = 60 (formerly 30)
  3210 
  3211 * Different bookkeeping for code equations (INCOMPATIBILITY):
  3212 
  3213   a) On theory merge, the last set of code equations for a particular
  3214      constant is taken (in accordance with the policy applied by other
  3215      parts of the code generator framework).
  3216 
  3217   b) Code equations stemming from explicit declarations (e.g. code
  3218      attribute) gain priority over default code equations stemming
  3219      from definition, primrec, fun etc.
  3220 
  3221 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  3222 
  3223 * Unified theorem tables for both code generators.  Thus [code
  3224 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  3225 
  3226 * Command 'find_consts' searches for constants based on type and name
  3227 patterns, e.g.
  3228 
  3229     find_consts "_ => bool"
  3230 
  3231 By default, matching is against subtypes, but it may be restricted to
  3232 the whole type.  Searching by name is possible.  Multiple queries are
  3233 conjunctive and queries may be negated by prefixing them with a
  3234 hyphen:
  3235 
  3236     find_consts strict: "_ => bool" name: "Int" -"int => int"
  3237 
  3238 * New 'find_theorems' criterion "solves" matches theorems that
  3239 directly solve the current goal (modulo higher-order unification).
  3240 
  3241 * Auto solve feature for main theorem statements: whenever a new goal
  3242 is stated, "find_theorems solves" is called; any theorems that could
  3243 solve the lemma directly are listed as part of the goal state.
  3244 Cf. associated options in Proof General Isabelle settings menu,
  3245 enabled by default, with reasonable timeout for pathological cases of
  3246 higher-order unification.
  3247 
  3248 
  3249 *** Document preparation ***
  3250 
  3251 * Antiquotation @{lemma} now imitates a regular terminal proof,
  3252 demanding keyword 'by' and supporting the full method expression
  3253 syntax just like the Isar command 'by'.
  3254 
  3255 
  3256 *** HOL ***
  3257 
  3258 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  3259 points Main and Complex_Main remain as before.
  3260 
  3261 * Logic image HOL-Plain provides a minimal HOL with the most important
  3262 tools available (inductive, datatype, primrec, ...).  This facilitates
  3263 experimentation and tool development.  Note that user applications
  3264 (and library theories) should never refer to anything below theory
  3265 Main, as before.
  3266 
  3267 * Logic image HOL-Main stops at theory Main, and thus facilitates
  3268 experimentation due to shorter build times.
  3269 
  3270 * Logic image HOL-NSA contains theories of nonstandard analysis which
  3271 were previously part of former HOL-Complex.  Entry point Hyperreal
  3272 remains valid, but theories formerly using Complex_Main should now use
  3273 new entry point Hypercomplex.
  3274 
  3275 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  3276 Posix processes.  Avoids potentially expensive forking of the ML
  3277 process.  New thread-based implementation also works on non-Unix
  3278 platforms (Cygwin).  Provers are no longer hardwired, but defined
  3279 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  3280 commands are covered in the isar-ref manual.
  3281 
  3282 * Wrapper scripts for remote SystemOnTPTP service allows to use
  3283 sledgehammer without local ATP installation (Vampire etc.). Other
  3284 provers may be included via suitable ML wrappers, see also
  3285 src/HOL/ATP_Linkup.thy.
  3286 
  3287 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  3288 menu.
  3289 
  3290 * The metis method no longer fails because the theorem is too trivial
  3291 (contains the empty clause).
  3292 
  3293 * The metis method now fails in the usual manner, rather than raising
  3294 an exception, if it determines that it cannot prove the theorem.
  3295 
  3296 * Method "coherent" implements a prover for coherent logic (see also
  3297 src/Tools/coherent.ML).
  3298 
  3299 * Constants "undefined" and "default" replace "arbitrary".  Usually
  3300 "undefined" is the right choice to replace "arbitrary", though
  3301 logically there is no difference.  INCOMPATIBILITY.
  3302 
  3303 * Command "value" now integrates different evaluation mechanisms.  The
  3304 result of the first successful evaluation mechanism is printed.  In
  3305 square brackets a particular named evaluation mechanisms may be
  3306 specified (currently, [SML], [code] or [nbe]).  See further
  3307 src/HOL/ex/Eval_Examples.thy.
  3308 
  3309 * Normalization by evaluation now allows non-leftlinear equations.
  3310 Declare with attribute [code nbe].
  3311 
  3312 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  3313 as the structured Isar versions "cases" and "induct", cf. the
  3314 corresponding "cases" and "induct" attributes.  Mutual induction rules
  3315 are now presented as a list of individual projections
  3316 (e.g. foo_bar.inducts for types foo and bar); the old format with
  3317 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  3318 rare situations a different rule is selected --- notably nested tuple
  3319 elimination instead of former prod.exhaust: use explicit (case_tac t
  3320 rule: prod.exhaust) here.
  3321 
  3322 * Attributes "cases", "induct", "coinduct" support "del" option.
  3323 
  3324 * Removed fact "case_split_thm", which duplicates "case_split".
  3325 
  3326 * The option datatype has been moved to a new theory Option.  Renamed
  3327 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  3328 
  3329 * New predicate "strict_mono" classifies strict functions on partial
  3330 orders.  With strict functions on linear orders, reasoning about
  3331 (in)equalities is facilitated by theorems "strict_mono_eq",
  3332 "strict_mono_less_eq" and "strict_mono_less".
  3333 
  3334 * Some set operations are now proper qualified constants with
  3335 authentic syntax.  INCOMPATIBILITY:
  3336 
  3337     op Int ~>   Set.Int
  3338     op Un ~>    Set.Un
  3339     INTER ~>    Set.INTER
  3340     UNION ~>    Set.UNION
  3341     Inter ~>    Set.Inter
  3342     Union ~>    Set.Union
  3343     {} ~>       Set.empty
  3344     UNIV ~>     Set.UNIV
  3345 
  3346 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  3347 theory Set.
  3348 
  3349 * Auxiliary class "itself" has disappeared -- classes without any
  3350 parameter are treated as expected by the 'class' command.
  3351 
  3352 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  3353 
  3354 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  3355 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  3356 
  3357 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  3358 method "approximation".  It proves formulas on real values by using
  3359 interval arithmetic.  In the formulas are also the transcendental
  3360 functions sin, cos, tan, atan, ln, exp and the constant pi are
  3361 allowed. For examples see
  3362 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  3363 
  3364 * Theory "Reflection" now resides in HOL/Library.
  3365 
  3366 * Entry point to Word library now simply named "Word".
  3367 INCOMPATIBILITY.
  3368 
  3369 * Made source layout more coherent with logical distribution
  3370 structure:
  3371 
  3372     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  3373     src/HOL/Library/Code_Message.thy ~> src/HOL/
  3374     src/HOL/Library/GCD.thy ~> src/HOL/
  3375     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  3376     src/HOL/Library/Parity.thy ~> src/HOL/
  3377     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  3378     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  3379     src/HOL/Real/Lubs.thy ~> src/HOL/
  3380     src/HOL/Real/PReal.thy ~> src/HOL/
  3381     src/HOL/Real/Rational.thy ~> src/HOL/
  3382     src/HOL/Real/RComplete.thy ~> src/HOL/
  3383     src/HOL/Real/RealDef.thy ~> src/HOL/
  3384     src/HOL/Real/RealPow.thy ~> src/HOL/
  3385     src/HOL/Real/Real.thy ~> src/HOL/
  3386     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  3387     src/HOL/Complex/Complex.thy ~> src/HOL/
  3388     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  3389     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  3390     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  3391     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  3392     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  3393     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  3394     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  3395     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  3396     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  3397     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  3398     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  3399     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  3400     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  3401     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  3402     src/HOL/Real/Float ~> src/HOL/Library/
  3403     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  3404     src/HOL/Real/RealVector.thy ~> src/HOL/
  3405 
  3406     src/HOL/arith_data.ML ~> src/HOL/Tools
  3407     src/HOL/hologic.ML ~> src/HOL/Tools
  3408     src/HOL/simpdata.ML ~> src/HOL/Tools
  3409     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3410     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3411     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3412     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3413     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3414     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3415     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3416 
  3417     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3418     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3419     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3420     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3421     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3422     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3423 
  3424 * If methods "eval" and "evaluation" encounter a structured proof
  3425 state with !!/==>, only the conclusion is evaluated to True (if
  3426 possible), avoiding strange error messages.
  3427 
  3428 * Method "sizechange" automates termination proofs using (a
  3429 modification of) the size-change principle.  Requires SAT solver.  See
  3430 src/HOL/ex/Termination.thy for examples.
  3431 
  3432 * Simplifier: simproc for let expressions now unfolds if bound
  3433 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3434 
  3435 * Method "arith": Linear arithmetic now ignores all inequalities when
  3436 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3437 
  3438 * New attribute "arith" for facts that should always be used
  3439 automatically by arithmetic. It is intended to be used locally in
  3440 proofs, e.g.
  3441 
  3442   assumes [arith]: "x > 0"
  3443 
  3444 Global usage is discouraged because of possible performance impact.
  3445 
  3446 * New classes "top" and "bot" with corresponding operations "top" and
  3447 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3448 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3449 
  3450 * Changed definition lemma "less_fun_def" in order to provide an
  3451 instance for preorders on functions; use lemma "less_le" instead.
  3452 INCOMPATIBILITY.
  3453 
  3454 * Theory Orderings: class "wellorder" moved here, with explicit
  3455 induction rule "less_induct" as assumption.  For instantiation of
  3456 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3457 INCOMPATIBILITY.
  3458 
  3459 * Theory Orderings: added class "preorder" as superclass of "order".
  3460 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3461 etc. slightly changed.  Some theorems named order_class.* now named
  3462 preorder_class.*.
  3463 
  3464 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3465 "diag" to "Id_on".
  3466 
  3467 * Theory Finite_Set: added a new fold combinator of type
  3468 
  3469   ('a => 'b => 'b) => 'b => 'a set => 'b
  3470 
  3471 Occasionally this is more convenient than the old fold combinator
  3472 which is now defined in terms of the new one and renamed to
  3473 fold_image.
  3474 
  3475 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3476 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3477 extended with further lemmas!).  At the moment both still exist but
  3478 the former will disappear at some point.
  3479 
  3480 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3481 class recpower.  Type-specific simp rules for various recpower types
  3482 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3483 
  3484 rat_power_0    -> power_0
  3485 rat_power_Suc  -> power_Suc
  3486 realpow_0      -> power_0
  3487 realpow_Suc    -> power_Suc
  3488 complexpow_0   -> power_0
  3489 complexpow_Suc -> power_Suc
  3490 power_poly_0   -> power_0
  3491 power_poly_Suc -> power_Suc
  3492 
  3493 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3494 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3495 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3496 of lemmas from Divides has been generalized from nat to class
  3497 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3498 renames resulting from duplicate elimination:
  3499 
  3500     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3501     zero_dvd_iff ~>         dvd_0_left_iff
  3502     dvd_0 ~>                dvd_0_right
  3503     DIVISION_BY_ZERO_DIV ~> div_by_0
  3504     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3505     mult_div ~>             div_mult_self2_is_id
  3506     mult_mod ~>             mod_mult_self2_is_0
  3507 
  3508 * Theory IntDiv: removed many lemmas that are instances of class-based
  3509 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3510 rename old lemmas as follows:
  3511 
  3512 dvd_diff               -> nat_dvd_diff
  3513 dvd_zminus_iff         -> dvd_minus_iff
  3514 mod_add1_eq            -> mod_add_eq
  3515 mod_mult1_eq           -> mod_mult_right_eq
  3516 mod_mult1_eq'          -> mod_mult_left_eq
  3517 mod_mult_distrib_mod   -> mod_mult_eq
  3518 nat_mod_add_left_eq    -> mod_add_left_eq
  3519 nat_mod_add_right_eq   -> mod_add_right_eq
  3520 nat_mod_div_trivial    -> mod_div_trivial
  3521 nat_mod_mod_trivial    -> mod_mod_trivial
  3522 zdiv_zadd_self1        -> div_add_self1
  3523 zdiv_zadd_self2        -> div_add_self2
  3524 zdiv_zmult_self1       -> div_mult_self2_is_id
  3525 zdiv_zmult_self2       -> div_mult_self1_is_id
  3526 zdvd_triv_left         -> dvd_triv_left
  3527 zdvd_triv_right        -> dvd_triv_right
  3528 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3529 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3530 zmod_zadd_left_eq      -> mod_add_left_eq
  3531 zmod_zadd_right_eq     -> mod_add_right_eq
  3532 zmod_zadd_self1        -> mod_add_self1
  3533 zmod_zadd_self2        -> mod_add_self2
  3534 zmod_zadd1_eq          -> mod_add_eq
  3535 zmod_zdiff1_eq         -> mod_diff_eq
  3536 zmod_zdvd_zmod         -> mod_mod_cancel
  3537 zmod_zmod_cancel       -> mod_mod_cancel
  3538 zmod_zmult_self1       -> mod_mult_self2_is_0
  3539 zmod_zmult_self2       -> mod_mult_self1_is_0
  3540 zmod_1                 -> mod_by_1
  3541 zdiv_1                 -> div_by_1
  3542 zdvd_abs1              -> abs_dvd_iff
  3543 zdvd_abs2              -> dvd_abs_iff
  3544 zdvd_refl              -> dvd_refl
  3545 zdvd_trans             -> dvd_trans
  3546 zdvd_zadd              -> dvd_add
  3547 zdvd_zdiff             -> dvd_diff
  3548 zdvd_zminus_iff        -> dvd_minus_iff
  3549 zdvd_zminus2_iff       -> minus_dvd_iff
  3550 zdvd_zmultD            -> dvd_mult_right
  3551 zdvd_zmultD2           -> dvd_mult_left
  3552 zdvd_zmult_mono        -> mult_dvd_mono
  3553 zdvd_0_right           -> dvd_0_right
  3554 zdvd_0_left            -> dvd_0_left_iff
  3555 zdvd_1_left            -> one_dvd
  3556 zminus_dvd_iff         -> minus_dvd_iff
  3557 
  3558 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3559 
  3560 * The real numbers offer decimal input syntax: 12.34 is translated
  3561 into 1234/10^2. This translation is not reversed upon output.
  3562 
  3563 * Theory Library/Polynomial defines an abstract type 'a poly of
  3564 univariate polynomials with coefficients of type 'a.  In addition to
  3565 the standard ring operations, it also supports div and mod.  Code
  3566 generation is also supported, using list-style constructors.
  3567 
  3568 * Theory Library/Inner_Product defines a class of real_inner for real
  3569 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3570 => real.  Class real_inner is a subclass of real_normed_vector from
  3571 theory RealVector.
  3572 
  3573 * Theory Library/Product_Vector provides instances for the product
  3574 type 'a * 'b of several classes from RealVector and Inner_Product.
  3575 Definitions of addition, subtraction, scalar multiplication, norms,
  3576 and inner products are included.
  3577 
  3578 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3579 addition to the field operations, numerals and case syntax are also
  3580 supported.
  3581 
  3582 * Theory Library/Diagonalize provides constructive version of Cantor's
  3583 first diagonalization argument.
  3584 
  3585 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3586 zlcm (for int); carried together from various gcd/lcm developements in
  3587 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3588 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3589 may recover tupled syntax as follows:
  3590 
  3591     hide (open) const gcd
  3592     abbreviation gcd where
  3593       "gcd == (%(a, b). GCD.gcd a b)"
  3594     notation (output)
  3595       GCD.gcd ("gcd '(_, _')")
  3596 
  3597 The same works for lcm, zgcd, zlcm.
  3598 
  3599 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3600 instantiations for algebraic structures.  Removed some duplicate
  3601 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3602 
  3603 * ML antiquotation @{code} takes a constant as argument and generates
  3604 corresponding code in background and inserts name of the corresponding
  3605 resulting ML value/function/datatype constructor binding in place.
  3606 All occurrences of @{code} with a single ML block are generated
  3607 simultaneously.  Provides a generic and safe interface for
  3608 instrumentalizing code generation.  See
  3609 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3610 In future you ought to refrain from ad-hoc compiling generated SML
  3611 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3612 cannot refer to constants for which user-defined serializations are
  3613 set.  Refer to the corresponding ML counterpart directly in that
  3614 cases.
  3615 
  3616 * Command 'rep_datatype': instead of theorem names the command now
  3617 takes a list of terms denoting the constructors of the type to be
  3618 represented as datatype.  The characteristic theorems have to be
  3619 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3620 have disappeared in favour of existing ones:
  3621 
  3622     unit_induct                 ~> unit.induct
  3623     prod_induct                 ~> prod.induct
  3624     sum_induct                  ~> sum.induct
  3625     Suc_Suc_eq                  ~> nat.inject
  3626     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3627 
  3628 
  3629 *** HOL-Algebra ***
  3630 
  3631 * New locales for orders and lattices where the equivalence relation
  3632 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3633 locales use a record structure with field eq for the equivalence.
  3634 
  3635 * New theory of factorial domains.
  3636 
  3637 * Units_l_inv and Units_r_inv are now simp rules by default.
  3638 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3639 and/or r_inv will now also require deletion of these lemmas.
  3640 
  3641 * Renamed the following theorems, INCOMPATIBILITY:
  3642 
  3643 UpperD ~> Upper_memD
  3644 LowerD ~> Lower_memD
  3645 least_carrier ~> least_closed
  3646 greatest_carrier ~> greatest_closed
  3647 greatest_Lower_above ~> greatest_Lower_below
  3648 one_zero ~> carrier_one_zero
  3649 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3650 
  3651 
  3652 *** HOL-Nominal ***
  3653 
  3654 * Nominal datatypes can now contain type-variables.
  3655 
  3656 * Commands 'nominal_inductive' and 'equivariance' work with local
  3657 theory targets.
  3658 
  3659 * Nominal primrec can now works with local theory targets and its
  3660 specification syntax now conforms to the general format as seen in
  3661 'inductive' etc.
  3662 
  3663 * Method "perm_simp" honours the standard simplifier attributes
  3664 (no_asm), (no_asm_use) etc.
  3665 
  3666 * The new predicate #* is defined like freshness, except that on the
  3667 left hand side can be a set or list of atoms.
  3668 
  3669 * Experimental command 'nominal_inductive2' derives strong induction
  3670 principles for inductive definitions.  In contrast to
  3671 'nominal_inductive', which can only deal with a fixed number of
  3672 binders, it can deal with arbitrary expressions standing for sets of
  3673 atoms to be avoided.  The only inductive definition we have at the
  3674 moment that needs this generalisation is the typing rule for Lets in
  3675 the algorithm W:
  3676 
  3677  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3678  -----------------------------------------------------------------
  3679          Gamma |- Let x be t1 in t2 : T2
  3680 
  3681 In this rule one wants to avoid all the binders that are introduced by
  3682 "close Gamma T1".  We are looking for other examples where this
  3683 feature might be useful.  Please let us know.
  3684 
  3685 
  3686 *** HOLCF ***
  3687 
  3688 * Reimplemented the simplification procedure for proving continuity
  3689 subgoals.  The new simproc is extensible; users can declare additional
  3690 continuity introduction rules with the attribute [cont2cont].
  3691 
  3692 * The continuity simproc now uses a different introduction rule for
  3693 solving continuity subgoals on terms with lambda abstractions.  In
  3694 some rare cases the new simproc may fail to solve subgoals that the
  3695 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3696 Potential INCOMPATIBILITY.
  3697 
  3698 * Command 'fixrec': specification syntax now conforms to the general
  3699 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3700 examples.  INCOMPATIBILITY.
  3701 
  3702 
  3703 *** ZF ***
  3704 
  3705 * Proof of Zorn's Lemma for partial orders.
  3706 
  3707 
  3708 *** ML ***
  3709 
  3710 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3711 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3712 depends on multithreading, so timouts will not work before Poly/ML
  3713 5.2.1!
  3714 
  3715 * High-level support for concurrent ML programming, see
  3716 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3717 particularly convenient to organize independent functional
  3718 computations.  The concept of "synchronized variables" provides a
  3719 higher-order interface for components with shared state, avoiding the
  3720 delicate details of mutexes and condition variables.  (Requires
  3721 Poly/ML 5.2.1 or later.)
  3722 
  3723 * ML bindings produced via Isar commands are stored within the Isar
  3724 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3725 become thread-safe and work with undo as expected (concerning
  3726 top-level bindings, not side-effects on global references).
  3727 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3728 compiler at runtime; really global bindings need to be given outside a
  3729 theory.  (Requires Poly/ML 5.2 or later.)
  3730 
  3731 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3732 context.  Top-level ML bindings are stored within the proof context in
  3733 a purely sequential fashion, disregarding the nested proof structure.
  3734 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3735 proof.  (Requires Poly/ML 5.2 or later.)
  3736 
  3737 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3738 and Method.setup, as well as Isar commands 'attribute_setup' and
  3739 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3740 existing code accordingly, or use plain 'setup' together with old
  3741 Method.add_method.
  3742 
  3743 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3744 to 'a -> thm, while results are always tagged with an authentic oracle
  3745 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3746 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3747 accordingly.  Note that extra performance may be gained by producing
  3748 the cterm carefully, avoiding slow Thm.cterm_of.
  3749 
  3750 * Simplified interface for defining document antiquotations via
  3751 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3752 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3753 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3754 examples.
  3755 
  3756 * More systematic treatment of long names, abstract name bindings, and
  3757 name space operations.  Basic operations on qualified names have been
  3758 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3759 Long_Name.append.  Old type bstring has been mostly replaced by
  3760 abstract type binding (see structure Binding), which supports precise
  3761 qualification by packages and local theory targets, as well as proper
  3762 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3763 bstring values into Binding.name, or better pass through abstract
  3764 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3765 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3766 
  3767 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3768 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3769 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3770 
  3771 * Disposed old type and term read functions (Sign.read_def_typ,
  3772 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3773 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3774 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3775 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3776 resort for legacy applications.
  3777 
  3778 * Disposed old declarations, tactics, tactic combinators that refer to
  3779 the simpset or claset of an implicit theory (such as Addsimps,
  3780 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3781 embedded ML text, or local_simpset_of with a proper context passed as
  3782 explicit runtime argument.
  3783 
  3784 * Rules and tactics that read instantiations (read_instantiate,
  3785 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3786 context, which is required for parsing and type-checking.  Moreover,
  3787 the variables are specified as plain indexnames, not string encodings
  3788 thereof.  INCOMPATIBILITY.
  3789 
  3790 * Generic Toplevel.add_hook interface allows to analyze the result of
  3791 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3792 for theorem dependency output of transactions resulting in a new
  3793 theory state.
  3794 
  3795 * ML antiquotations: block-structured compilation context indicated by
  3796 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3797 
  3798   @{binding name}                         - basic name binding
  3799   @{let ?pat = term}                      - term abbreviation (HO matching)
  3800   @{note name = fact}                     - fact abbreviation
  3801   @{thm fact}                             - singleton fact (with attributes)
  3802   @{thms fact}                            - general fact (with attributes)
  3803   @{lemma prop by method}                 - singleton goal
  3804   @{lemma prop by meth1 meth2}            - singleton goal
  3805   @{lemma prop1 ... propN by method}      - general goal
  3806   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3807   @{lemma (open) ...}                     - open derivation
  3808 
  3809 
  3810 *** System ***
  3811 
  3812 * The Isabelle "emacs" tool provides a specific interface to invoke
  3813 Proof General / Emacs, with more explicit failure if that is not
  3814 installed (the old isabelle-interface script silently falls back on
  3815 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3816 installation location of the Proof General distribution.
  3817 
  3818 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3819 the Isabelle process into a JVM/Scala application.  See
  3820 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3821 process wrapper has been discontinued.)
  3822 
  3823 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3824 
  3825 * Various status messages (with exact source position information) are
  3826 emitted, if proper markup print mode is enabled.  This allows
  3827 user-interface components to provide detailed feedback on internal
  3828 prover operations.
  3829 
  3830 
  3831 
  3832 New in Isabelle2008 (June 2008)
  3833 -------------------------------
  3834 
  3835 *** General ***
  3836 
  3837 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3838 and updated, with formally checked references as hyperlinks.
  3839 
  3840 * Theory loader: use_thy (and similar operations) no longer set the
  3841 implicit ML context, which was occasionally hard to predict and in
  3842 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3843 provides a proper context already.
  3844 
  3845 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3846 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3847 'use' within a theory file will do the job.
  3848 
  3849 * Name space merge now observes canonical order, i.e. the second space
  3850 is inserted into the first one, while existing entries in the first
  3851 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3852 swap theory imports.
  3853 
  3854 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3855 INCOMPATIBILITY in identifier syntax etc.
  3856 
  3857 * Outer syntax: string tokens no longer admit escaped white space,
  3858 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3859 white space without escapes.
  3860 
  3861 * Outer syntax: string tokens may contain arbitrary character codes
  3862 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3863 "foo_bar".
  3864 
  3865 
  3866 *** Pure ***
  3867 
  3868 * Context-dependent token translations.  Default setup reverts locally
  3869 fixed variables, and adds hilite markup for undeclared frees.
  3870 
  3871 * Unused theorems can be found using the new command 'unused_thms'.
  3872 There are three ways of invoking it:
  3873 
  3874 (1) unused_thms
  3875      Only finds unused theorems in the current theory.
  3876 
  3877 (2) unused_thms thy_1 ... thy_n -
  3878      Finds unused theorems in the current theory and all of its ancestors,
  3879      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3880 
  3881 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3882      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3883      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3884      their ancestors.
  3885 
  3886 In order to increase the readability of the list produced by
  3887 unused_thms, theorems that have been created by a particular instance
  3888 of a theory command such as 'inductive' or 'function' are considered
  3889 to belong to the same "group", meaning that if at least one theorem in
  3890 this group is used, the other theorems in the same group are no longer
  3891 reported as unused.  Moreover, if all theorems in the group are
  3892 unused, only one theorem in the group is displayed.
  3893 
  3894 Note that proof objects have to be switched on in order for
  3895 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3896 usually the case when using Proof General with the default settings).
  3897 
  3898 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3899 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3900 duplicate fact bindings, or even accidental fact duplications.  Note
  3901 that tools may maintain dynamically scoped facts systematically, using
  3902 PureThy.add_thms_dynamic.
  3903 
  3904 * Command 'hide' now allows to hide from "fact" name space as well.
  3905 
  3906 * Eliminated destructive theorem database, simpset, claset, and
  3907 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3908 update of theories within ML code.
  3909 
  3910 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3911 INCOMPATIBILITY, object-logics depending on former Pure require
  3912 additional setup PureThy.old_appl_syntax_setup; object-logics
  3913 depending on former CPure need to refer to Pure.
  3914 
  3915 * Commands 'use' and 'ML' are now purely functional, operating on
  3916 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3917 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3918 INCOMPATIBILITY.
  3919 
  3920 * Command 'setup': discontinued implicit version with ML reference.
  3921 
  3922 * Instantiation target allows for simultaneous specification of class
  3923 instance operations together with an instantiation proof.
  3924 Type-checking phase allows to refer to class operations uniformly.
  3925 See src/HOL/Complex/Complex.thy for an Isar example and
  3926 src/HOL/Library/Eval.thy for an ML example.
  3927 
  3928 * Indexing of literal facts: be more serious about including only
  3929 facts from the visible specification/proof context, but not the
  3930 background context (locale etc.).  Affects `prop` notation and method
  3931 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3932 situations.
  3933 
  3934 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3935 "(open)" option, which used to expose internal bound variables to the
  3936 proof text.
  3937 
  3938 * Isar statements: removed obsolete case "rule_context".
  3939 INCOMPATIBILITY, better use explicit fixes/assumes.
  3940 
  3941 * Locale proofs: default proof step now includes 'unfold_locales';
  3942 hence 'proof' without argument may be used to unfold locale
  3943 predicates.
  3944 
  3945 
  3946 *** Document preparation ***
  3947 
  3948 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3949 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3950 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3951 spot); renamed link color from "darkblue" to "linkcolor" (default
  3952 value unchanged, can be redefined via \definecolor); no longer sets
  3953 "a4paper" option (unnecessary or even intrusive).
  3954 
  3955 * Antiquotation @{lemma A method} proves proposition A by the given
  3956 method (either a method name or a method name plus (optional) method
  3957 arguments in parentheses) and prints A just like @{prop A}.
  3958 
  3959 
  3960 *** HOL ***
  3961 
  3962 * New primrec package.  Specification syntax conforms in style to
  3963 definition/function/....  No separate induction rule is provided.  The
  3964 "primrec" command distinguishes old-style and new-style specifications
  3965 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3966 When adjusting theories, beware: constants stemming from new-style
  3967 primrec specifications have authentic syntax.
  3968 
  3969 * Metis prover is now an order of magnitude faster, and also works
  3970 with multithreading.
  3971 
  3972 * Metis: the maximum number of clauses that can be produced from a
  3973 theorem is now given by the attribute max_clauses.  Theorems that
  3974 exceed this number are ignored, with a warning printed.
  3975 
  3976 * Sledgehammer no longer produces structured proofs by default. To
  3977 enable, declare [[sledgehammer_full = true]].  Attributes
  3978 reconstruction_modulus, reconstruction_sorts renamed
  3979 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3980 
  3981 * Method "induct_scheme" derives user-specified induction rules
  3982 from well-founded induction and completeness of patterns. This factors
  3983 out some operations that are done internally by the function package
  3984 and makes them available separately.  See
  3985 src/HOL/ex/Induction_Scheme.thy for examples.
  3986 
  3987 * More flexible generation of measure functions for termination
  3988 proofs: Measure functions can be declared by proving a rule of the
  3989 form "is_measure f" and giving it the [measure_function] attribute.
  3990 The "is_measure" predicate is logically meaningless (always true), and
  3991 just guides the heuristic.  To find suitable measure functions, the
  3992 termination prover sets up the goal "is_measure ?f" of the appropriate
  3993 type and generates all solutions by prolog-style backwards proof using
  3994 the declared rules.
  3995 
  3996 This setup also deals with rules like 
  3997 
  3998   "is_measure f ==> is_measure (list_size f)"
  3999 
  4000 which accommodates nested datatypes that recurse through lists.
  4001 Similar rules are predeclared for products and option types.
  4002 
  4003 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  4004 
  4005   INCOMPATIBILITIES:
  4006 
  4007   - Definitions of overloaded constants on sets have to be replaced by
  4008     definitions on => and bool.
  4009 
  4010   - Some definitions of overloaded operators on sets can now be proved
  4011     using the definitions of the operators on => and bool.  Therefore,
  4012     the following theorems have been renamed:
  4013 
  4014       subset_def   -> subset_eq
  4015       psubset_def  -> psubset_eq
  4016       set_diff_def -> set_diff_eq
  4017       Compl_def    -> Compl_eq
  4018       Sup_set_def  -> Sup_set_eq
  4019       Inf_set_def  -> Inf_set_eq
  4020       sup_set_def  -> sup_set_eq
  4021       inf_set_def  -> inf_set_eq
  4022 
  4023   - Due to the incompleteness of the HO unification algorithm, some
  4024     rules such as subst may require manual instantiation, if some of
  4025     the unknowns in the rule is a set.
  4026 
  4027   - Higher order unification and forward proofs:
  4028     The proof pattern
  4029 
  4030       have "P (S::'a set)" <...>
  4031       then have "EX S. P S" ..
  4032 
  4033     no longer works (due to the incompleteness of the HO unification
  4034     algorithm) and must be replaced by the pattern
  4035 
  4036       have "EX S. P S"
  4037       proof
  4038         show "P S" <...>
  4039       qed
  4040 
  4041   - Calculational reasoning with subst (or similar rules):
  4042     The proof pattern
  4043 
  4044       have "P (S::'a set)" <...>
  4045       also have "S = T" <...>
  4046       finally have "P T" .
  4047 
  4048     no longer works (for similar reasons as the previous example) and
  4049     must be replaced by something like
  4050 
  4051       have "P (S::'a set)" <...>
  4052       moreover have "S = T" <...>
  4053       ultimately have "P T" by simp
  4054 
  4055   - Tactics or packages written in ML code:
  4056     Code performing pattern matching on types via
  4057 
  4058       Type ("set", [T]) => ...
  4059 
  4060     must be rewritten. Moreover, functions like strip_type or
  4061     binder_types no longer return the right value when applied to a
  4062     type of the form
  4063 
  4064       T1 => ... => Tn => U => bool
  4065 
  4066     rather than
  4067 
  4068       T1 => ... => Tn => U set
  4069 
  4070 * Merged theories Wellfounded_Recursion, Accessible_Part and
  4071 Wellfounded_Relations to theory Wellfounded.
  4072 
  4073 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  4074 
  4075 * Class finite no longer treats UNIV as class parameter.  Use class
  4076 enum from theory Library/Enum instead to achieve a similar effect.
  4077 INCOMPATIBILITY.
  4078 
  4079 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  4080 and "Cons".  INCOMPATIBILITY.
  4081 
  4082 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  4083 Potential INCOMPATIBILITY.
  4084 
  4085 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  4086 injective_fst_snd removed, use split_eta and prod_eqI instead.
  4087 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  4088 
  4089 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  4090 the same name in theory Orderings:
  4091 
  4092   less_trans
  4093   less_linear
  4094   le_imp_less_or_eq
  4095   le_less_trans
  4096   less_le_trans
  4097   less_not_sym
  4098   less_asym
  4099 
  4100 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  4101 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  4102 and different variable names.
  4103 
  4104 * Library/Option_ord.thy: Canonical order on option type.
  4105 
  4106 * Library/RBT.thy: Red-black trees, an efficient implementation of
  4107 finite maps.
  4108 
  4109 * Library/Countable.thy: Type class for countable types.
  4110 
  4111 * Theory Int: The representation of numerals has changed.  The infix
  4112 operator BIT and the bit datatype with constructors B0 and B1 have
  4113 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  4114 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  4115 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  4116 accordingly.
  4117 
  4118 * Theory Nat: definition of <= and < on natural numbers no longer
  4119 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  4120 le_def and less_def have disappeared.  Consider lemmas not_less
  4121 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  4122 
  4123 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  4124 (whose purpose mainly is for various fold_set functionals) have been
  4125 abandoned in favor of the existing algebraic classes
  4126 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  4127 lower_semilattice (resp. upper_semilattice) and linorder.
  4128 INCOMPATIBILITY.
  4129 
  4130 * Theory Transitive_Closure: induct and cases rules now declare proper
  4131 case_names ("base" and "step").  INCOMPATIBILITY.
  4132 
  4133 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  4134 lattices.  The form set-specific version is available as
  4135 Inductive.lfp_ordinal_induct_set.
  4136 
  4137 * Renamed theorems "power.simps" to "power_int.simps".
  4138 INCOMPATIBILITY.
  4139 
  4140 * Class semiring_div provides basic abstract properties of semirings
  4141 with division and modulo operations.  Subsumes former class dvd_mod.
  4142 
  4143 * Merged theories IntDef, Numeral and IntArith into unified theory
  4144 Int.  INCOMPATIBILITY.
  4145 
  4146 * Theory Library/Code_Index: type "index" now represents natural
  4147 numbers rather than integers.  INCOMPATIBILITY.
  4148 
  4149 * New class "uminus" with operation "uminus" (split of from class
  4150 "minus" which now only has operation "minus", binary).
  4151 INCOMPATIBILITY.
  4152 
  4153 * Constants "card", "internal_split", "option_map" now with authentic
  4154 syntax.  INCOMPATIBILITY.
  4155 
  4156 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  4157 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  4158 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  4159 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  4160 Sup_set_def, le_def, less_def, option_map_def now with object
  4161 equality.  INCOMPATIBILITY.
  4162 
  4163 * Records. Removed K_record, and replaced it by pure lambda term
  4164 %x. c. The simplifier setup is now more robust against eta expansion.
  4165 INCOMPATIBILITY: in cases explicitly referring to K_record.
  4166 
  4167 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  4168 
  4169 * Library/ListVector: new theory of arithmetic vector operations.
  4170 
  4171 * Library/Order_Relation: new theory of various orderings as sets of
  4172 pairs.  Defines preorders, partial orders, linear orders and
  4173 well-orders on sets and on types.
  4174 
  4175 
  4176 *** ZF ***
  4177 
  4178 * Renamed some theories to allow to loading both ZF and HOL in the
  4179 same session:
  4180 
  4181   Datatype  -> Datatype_ZF
  4182   Inductive -> Inductive_ZF
  4183   Int       -> Int_ZF
  4184   IntDiv    -> IntDiv_ZF
  4185   Nat       -> Nat_ZF
  4186   List      -> List_ZF
  4187   Main      -> Main_ZF
  4188 
  4189 INCOMPATIBILITY: ZF theories that import individual theories below
  4190 Main might need to be adapted.  Regular theory Main is still
  4191 available, as trivial extension of Main_ZF.
  4192 
  4193 
  4194 *** ML ***
  4195 
  4196 * ML within Isar: antiquotation @{const name} or @{const
  4197 name(typargs)} produces statically-checked Const term.
  4198 
  4199 * Functor NamedThmsFun: data is available to the user as dynamic fact
  4200 (of the same name).  Removed obsolete print command.
  4201 
  4202 * Removed obsolete "use_legacy_bindings" function.
  4203 
  4204 * The ``print mode'' is now a thread-local value derived from a global
  4205 template (the former print_mode reference), thus access becomes
  4206 non-critical.  The global print_mode reference is for session
  4207 management only; user-code should use print_mode_value,
  4208 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  4209 
  4210 * Functions system/system_out provide a robust way to invoke external
  4211 shell commands, with propagation of interrupts (requires Poly/ML
  4212 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  4213 
  4214 
  4215 *** System ***
  4216 
  4217 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  4218 in accordance with Proof General 3.7, which prefers GNU emacs.
  4219 
  4220 * isatool tty runs Isabelle process with plain tty interaction;
  4221 optional line editor may be specified via ISABELLE_LINE_EDITOR
  4222 setting, the default settings attempt to locate "ledit" and "rlwrap".
  4223 
  4224 * isatool browser now works with Cygwin as well, using general
  4225 "javapath" function defined in Isabelle process environment.
  4226 
  4227 * YXML notation provides a simple and efficient alternative to
  4228 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  4229 isatool yxml as described in the Isabelle system manual.
  4230 
  4231 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  4232 provides general wrapper for managing an Isabelle process in a robust
  4233 fashion, with ``cooked'' output from stdin/stderr.
  4234 
  4235 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  4236 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  4237 
  4238 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  4239 way of changing the user's settings is via
  4240 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  4241 script.
  4242 
  4243 * Multithreading.max_threads := 0 refers to the number of actual CPU
  4244 cores of the underlying machine, which is a good starting point for
  4245 optimal performance tuning.  The corresponding usedir option -M allows
  4246 "max" as an alias for "0".  WARNING: does not work on certain versions
  4247 of Mac OS (with Poly/ML 5.1).
  4248 
  4249 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  4250 adverse effect of Isabelle flooding interactive front-ends (notably
  4251 ProofGeneral / XEmacs).
  4252 
  4253 
  4254 
  4255 New in Isabelle2007 (November 2007)
  4256 -----------------------------------
  4257 
  4258 *** General ***
  4259 
  4260 * More uniform information about legacy features, notably a
  4261 warning/error of "Legacy feature: ...", depending on the state of the
  4262 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  4263 legacy features will disappear eventually.
  4264 
  4265 * Theory syntax: the header format ``theory A = B + C:'' has been
  4266 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  4267 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  4268 
  4269 * Theory syntax: the old non-Isar theory file format has been
  4270 discontinued altogether.  Note that ML proof scripts may still be used
  4271 with Isar theories; migration is usually quite simple with the ML
  4272 function use_legacy_bindings.  INCOMPATIBILITY.
  4273 
  4274 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  4275 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  4276 quotes.
  4277 
  4278 * Theory loader: be more serious about observing the static theory
  4279 header specifications (including optional directories), but not the
  4280 accidental file locations of previously successful loads.  The strict
  4281 update policy of former update_thy is now already performed by
  4282 use_thy, so the former has been removed; use_thys updates several
  4283 theories simultaneously, just as 'imports' within a theory header
  4284 specification, but without merging the results.  Potential
  4285 INCOMPATIBILITY: may need to refine theory headers and commands
  4286 ROOT.ML which depend on load order.
  4287 
  4288 * Theory loader: optional support for content-based file
  4289 identification, instead of the traditional scheme of full physical
  4290 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  4291 (cf. the system manual).  The new scheme allows to work with
  4292 non-finished theories in persistent session images, such that source
  4293 files may be moved later on without requiring reloads.
  4294 
  4295 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4296 file (with the same base name as the theory) are considered a legacy
  4297 feature, which will disappear eventually. Even now, the theory loader
  4298 no longer maintains dependencies on such files.
  4299 
  4300 * Syntax: the scope for resolving ambiguities via type-inference is
  4301 now limited to individual terms, instead of whole simultaneous
  4302 specifications as before. This greatly reduces the complexity of the
  4303 syntax module and improves flexibility by separating parsing and
  4304 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  4305 'fixes' etc.) are required in rare situations.
  4306 
  4307 * Syntax: constants introduced by new-style packages ('definition',
  4308 'abbreviation' etc.) are passed through the syntax module in
  4309 ``authentic mode''. This means that associated mixfix annotations
  4310 really stick to such constants, independently of potential name space
  4311 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  4312 trees are represented slightly differently, may need to adapt syntax
  4313 translations accordingly. Use CONST marker in 'translations' and
  4314 @{const_syntax} antiquotation in 'parse_translation' etc.
  4315 
  4316 * Legacy goal package: reduced interface to the bare minimum required
  4317 to keep existing proof scripts running.  Most other user-level
  4318 functions are now part of the OldGoals structure, which is *not* open
  4319 by default (consider isatool expandshort before open OldGoals).
  4320 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  4321 these tend to cause confusion about the actual goal (!) context being
  4322 used here, which is not necessarily the same as the_context().
  4323 
  4324 * Command 'find_theorems': supports "*" wild-card in "name:"
  4325 criterion; "with_dups" option.  Certain ProofGeneral versions might
  4326 support a specific search form (see ProofGeneral/CHANGES).
  4327 
  4328 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  4329 by default, which means that "prems" (and also "fixed variables") are
  4330 suppressed from proof state output.  Note that the ProofGeneral
  4331 settings mechanism allows to change and save options persistently, but
  4332 older versions of Isabelle will fail to start up if a negative prems
  4333 limit is imposed.
  4334 
  4335 * Local theory targets may be specified by non-nested blocks of
  4336 ``context/locale/class ... begin'' followed by ``end''.  The body may
  4337 contain definitions, theorems etc., including any derived mechanism
  4338 that has been implemented on top of these primitives.  This concept
  4339 generalizes the existing ``theorem (in ...)'' towards more versatility
  4340 and scalability.
  4341 
  4342 * Proof General interface: proper undo of final 'end' command;
  4343 discontinued Isabelle/classic mode (ML proof scripts).
  4344 
  4345 
  4346 *** Document preparation ***
  4347 
  4348 * Added antiquotation @{theory name} which prints the given name,
  4349 after checking that it refers to a valid ancestor theory in the
  4350 current context.
  4351 
  4352 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  4353 check the given source text as ML type/structure, printing verbatim.
  4354 
  4355 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  4356 "c args == rhs" given in the current context.  (Any number of
  4357 arguments may be given on the LHS.)
  4358 
  4359 
  4360 *** Pure ***
  4361 
  4362 * The 'class' package offers a combination of axclass and locale to
  4363 achieve Haskell-like type classes in Isabelle.  Definitions and
  4364 theorems within a class context produce both relative results (with
  4365 implicit parameters according to the locale context), and polymorphic
  4366 constants with qualified polymorphism (according to the class
  4367 context).  Within the body context of a 'class' target, a separate
  4368 syntax layer ("user space type system") takes care of converting
  4369 between global polymorphic consts and internal locale representation.
  4370 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  4371 "isatool doc classes" provides a tutorial.
  4372 
  4373 * Generic code generator framework allows to generate executable
  4374 code for ML and Haskell (including Isabelle classes).  A short usage
  4375 sketch:
  4376 
  4377     internal compilation:
  4378         export_code <list of constants (term syntax)> in SML
  4379     writing SML code to a file:
  4380         export_code <list of constants (term syntax)> in SML <filename>
  4381     writing OCaml code to a file:
  4382         export_code <list of constants (term syntax)> in OCaml <filename>
  4383     writing Haskell code to a bunch of files:
  4384         export_code <list of constants (term syntax)> in Haskell <filename>
  4385 
  4386     evaluating closed propositions to True/False using code generation:
  4387         method ``eval''
  4388 
  4389 Reasonable default setup of framework in HOL.
  4390 
  4391 Theorem attributs for selecting and transforming function equations theorems:
  4392 
  4393     [code fun]:        select a theorem as function equation for a specific constant
  4394     [code fun del]:    deselect a theorem as function equation for a specific constant
  4395     [code inline]:     select an equation theorem for unfolding (inlining) in place
  4396     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  4397 
  4398 User-defined serializations (target in {SML, OCaml, Haskell}):
  4399 
  4400     code_const <and-list of constants (term syntax)>
  4401       {(target) <and-list of const target syntax>}+
  4402 
  4403     code_type <and-list of type constructors>
  4404       {(target) <and-list of type target syntax>}+
  4405 
  4406     code_instance <and-list of instances>
  4407       {(target)}+
  4408         where instance ::= <type constructor> :: <class>
  4409 
  4410     code_class <and_list of classes>
  4411       {(target) <and-list of class target syntax>}+
  4412         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4413 
  4414 code_instance and code_class only are effective to target Haskell.
  4415 
  4416 For example usage see src/HOL/ex/Codegenerator.thy and
  4417 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4418 generation from Isabelle/HOL theories is available via "isatool doc
  4419 codegen".
  4420 
  4421 * Code generator: consts in 'consts_code' Isar commands are now
  4422 referred to by usual term syntax (including optional type
  4423 annotations).
  4424 
  4425 * Command 'no_translations' removes translation rules from theory
  4426 syntax.
  4427 
  4428 * Overloaded definitions are now actually checked for acyclic
  4429 dependencies.  The overloading scheme is slightly more general than
  4430 that of Haskell98, although Isabelle does not demand an exact
  4431 correspondence to type class and instance declarations.
  4432 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4433 exotic versions of overloading -- at the discretion of the user!
  4434 
  4435 Polymorphic constants are represented via type arguments, i.e. the
  4436 instantiation that matches an instance against the most general
  4437 declaration given in the signature.  For example, with the declaration
  4438 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4439 as c(nat).  Overloading is essentially simultaneous structural
  4440 recursion over such type arguments.  Incomplete specification patterns
  4441 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4442 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4443 Command 'print_theory' outputs the normalized system of recursive
  4444 equations, see section "definitions".
  4445 
  4446 * Configuration options are maintained within the theory or proof
  4447 context (with name and type bool/int/string), providing a very simple
  4448 interface to a poor-man's version of general context data.  Tools may
  4449 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4450 these values using Config.get etc.  Users may change options via an
  4451 associated attribute of the same name.  This form of context
  4452 declaration works particularly well with commands 'declare' or
  4453 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4454 very easy to avoid global references, which would not observe Isar
  4455 toplevel undo/redo and fail to work with multithreading.
  4456 
  4457 Various global ML references of Pure and HOL have been turned into
  4458 configuration options:
  4459 
  4460   Unify.search_bound		unify_search_bound
  4461   Unify.trace_bound		unify_trace_bound
  4462   Unify.trace_simp		unify_trace_simp
  4463   Unify.trace_types		unify_trace_types
  4464   Simplifier.simp_depth_limit	simp_depth_limit
  4465   Blast.depth_limit		blast_depth_limit
  4466   DatatypeProp.dtK		datatype_distinctness_limit
  4467   fast_arith_neq_limit  	fast_arith_neq_limit
  4468   fast_arith_split_limit	fast_arith_split_limit
  4469 
  4470 * Named collections of theorems may be easily installed as context
  4471 data using the functor NamedThmsFun (see also
  4472 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4473 attributes; there is also a toplevel print command.  This facility is
  4474 just a common case of general context data, which is the preferred way
  4475 for anything more complex than just a list of facts in canonical
  4476 order.
  4477 
  4478 * Isar: command 'declaration' augments a local theory by generic
  4479 declaration functions written in ML.  This enables arbitrary content
  4480 being added to the context, depending on a morphism that tells the
  4481 difference of the original declaration context wrt. the application
  4482 context encountered later on.
  4483 
  4484 * Isar: proper interfaces for simplification procedures.  Command
  4485 'simproc_setup' declares named simprocs (with match patterns, and body
  4486 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4487 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4488 
  4489 * Isar: an extra pair of brackets around attribute declarations
  4490 abbreviates a theorem reference involving an internal dummy fact,
  4491 which will be ignored later --- only the effect of the attribute on
  4492 the background context will persist.  This form of in-place
  4493 declarations is particularly useful with commands like 'declare' and
  4494 'using', for example ``have A using [[simproc a]] by simp''.
  4495 
  4496 * Isar: method "assumption" (and implicit closing of subproofs) now
  4497 takes simple non-atomic goal assumptions into account: after applying
  4498 an assumption as a rule the resulting subgoals are solved by atomic
  4499 assumption steps.  This is particularly useful to finish 'obtain'
  4500 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4501 without referring to the original premise "!!x. P x ==> thesis" in the
  4502 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4503 more permissive.
  4504 
  4505 * Isar: implicit use of prems from the Isar proof context is
  4506 considered a legacy feature.  Common applications like ``have A .''
  4507 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4508 referencing facts explicitly here improves readability and
  4509 maintainability of proof texts.
  4510 
  4511 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4512 the obtained context from the course of reasoning!  For example:
  4513 
  4514   assume "EX x y. A x & B y"   -- "any previous fact"
  4515   then guess x and y by clarify
  4516 
  4517 This technique is potentially adventurous, depending on the facts and
  4518 proof tools being involved here.
  4519 
  4520 * Isar: known facts from the proof context may be specified as literal
  4521 propositions, using ASCII back-quote syntax.  This works wherever
  4522 named facts used to be allowed so far, in proof commands, proof
  4523 methods, attributes etc.  Literal facts are retrieved from the context
  4524 according to unification of type and term parameters.  For example,
  4525 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4526 theorems in the current context, then these are valid literal facts:
  4527 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4528 
  4529 There is also a proof method "fact" which does the same composition
  4530 for explicit goal states, e.g. the following proof texts coincide with
  4531 certain special cases of literal facts:
  4532 
  4533   have "A" by fact                 ==  note `A`
  4534   have "A ==> B" by fact           ==  note `A ==> B`
  4535   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4536   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4537 
  4538 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4539 outer syntax.  Thus symbolic identifiers may be used without
  4540 additional white space in declarations like this: ``assume *: A''.
  4541 
  4542 * Isar: 'print_facts' prints all local facts of the current context,
  4543 both named and unnamed ones.
  4544 
  4545 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4546 
  4547   def x == "t" and y == "u"
  4548 
  4549 * Isar: added command 'unfolding', which is structurally similar to
  4550 'using', but affects both the goal state and facts by unfolding given
  4551 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4552 'unfolded' attribute may be replaced by first-class proof text.
  4553 
  4554 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4555 and command 'unfolding' now all support object-level equalities
  4556 (potentially conditional).  The underlying notion of rewrite rule is
  4557 analogous to the 'rule_format' attribute, but *not* that of the
  4558 Simplifier (which is usually more generous).
  4559 
  4560 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4561 premises of a theorem by n. Useful in conjunction with drule.
  4562 
  4563 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4564 method expression within a sandbox consisting of the first N
  4565 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4566 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4567 simplifies all new goals that emerge from applying rule foo to the
  4568 originally first one.
  4569 
  4570 * Isar: schematic goals are no longer restricted to higher-order
  4571 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4572 expected.
  4573 
  4574 * Isar: the conclusion of a long theorem statement is now either
  4575 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4576 (essentially a disjunction of cases with local parameters and
  4577 assumptions).  The latter allows to express general elimination rules
  4578 adequately; in this notation common elimination rules look like this:
  4579 
  4580   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4581     assumes "EX x. P x"
  4582     obtains x where "P x"
  4583 
  4584   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4585     assumes "A & B"
  4586     obtains A and B
  4587 
  4588   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4589     assumes "A | B"
  4590     obtains
  4591       A
  4592     | B
  4593 
  4594 The subsequent classical rules even refer to the formal "thesis"
  4595 explicitly:
  4596 
  4597   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4598     obtains "~ thesis"
  4599 
  4600   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4601     obtains "thesis ==> something"
  4602 
  4603 The actual proof of an 'obtains' statement is analogous to that of the
  4604 Isar proof element 'obtain', only that there may be several cases.
  4605 Optional case names may be specified in parentheses; these will be
  4606 available both in the present proof and as annotations in the
  4607 resulting rule, for later use with the 'cases' method (cf. attribute
  4608 case_names).
  4609 
  4610 * Isar: the assumptions of a long theorem statement are available as
  4611 "assms" fact in the proof context.  This is more appropriate than the
  4612 (historical) "prems", which refers to all assumptions of the current
  4613 context, including those from the target locale, proof body etc.
  4614 
  4615 * Isar: 'print_statement' prints theorems from the current theory or
  4616 proof context in long statement form, according to the syntax of a
  4617 top-level lemma.
  4618 
  4619 * Isar: 'obtain' takes an optional case name for the local context
  4620 introduction rule (default "that").
  4621 
  4622 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4623 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4624 to occur.
  4625 
  4626 * Pure: syntax "CONST name" produces a fully internalized constant
  4627 according to the current context.  This is particularly useful for
  4628 syntax translations that should refer to internal constant
  4629 representations independently of name spaces.
  4630 
  4631 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4632 instead of "FOO ". This allows multiple binder declarations to coexist
  4633 in the same context.  INCOMPATIBILITY.
  4634 
  4635 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4636 primitive that also works in a locale context (both for constants and
  4637 fixed variables). Type declaration and internal syntactic representation
  4638 of given constants retrieved from the context. Likewise, the
  4639 'no_notation' command allows to remove given syntax annotations from the
  4640 current context.
  4641 
  4642 * Isar/locales: new derived specification elements 'axiomatization',
  4643 'definition', 'abbreviation', which support type-inference, admit
  4644 object-level specifications (equality, equivalence).  See also the
  4645 isar-ref manual.  Examples:
  4646 
  4647   axiomatization
  4648     eq  (infix "===" 50) where
  4649     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4650 
  4651   definition "f x y = x + y + 1"
  4652   definition g where "g x = f x x"
  4653 
  4654   abbreviation
  4655     neq  (infix "=!=" 50) where
  4656     "x =!= y == ~ (x === y)"
  4657 
  4658 These specifications may be also used in a locale context.  Then the
  4659 constants being introduced depend on certain fixed parameters, and the
  4660 constant name is qualified by the locale base name.  An internal
  4661 abbreviation takes care for convenient input and output, making the
  4662 parameters implicit and using the original short name.  See also
  4663 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4664 entities from a monomorphic theory.
  4665 
  4666 Presently, abbreviations are only available 'in' a target locale, but
  4667 not inherited by general import expressions.  Also note that
  4668 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4669 'translations' in common applications.  The "no_abbrevs" print mode
  4670 prevents folding of abbreviations in term output.
  4671 
  4672 Concrete syntax is attached to specified constants in internal form,
  4673 independently of name spaces.  The parse tree representation is
  4674 slightly different -- use 'notation' instead of raw 'syntax', and
  4675 'translations' with explicit "CONST" markup to accommodate this.
  4676 
  4677 * Pure/Isar: unified syntax for new-style specification mechanisms
  4678 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4679 full type inference and dummy patterns ("_").  For example:
  4680 
  4681   definition "K x _ = x"
  4682 
  4683   inductive conj for A B
  4684   where "A ==> B ==> conj A B"
  4685 
  4686 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4687 the current context.  Print mode "no_abbrevs" prevents inversion of
  4688 abbreviations on output.
  4689 
  4690 * Isar/locales: improved parameter handling: use of locales "var" and
  4691 "struct" no longer necessary; - parameter renamings are no longer
  4692 required to be injective.  For example, this allows to define
  4693 endomorphisms as locale endom = homom mult mult h.
  4694 
  4695 * Isar/locales: changed the way locales with predicates are defined.
  4696 Instead of accumulating the specification, the imported expression is
  4697 now an interpretation.  INCOMPATIBILITY: different normal form of
  4698 locale expressions.  In particular, in interpretations of locales with
  4699 predicates, goals repesenting already interpreted fragments are not
  4700 removed automatically.  Use methods `intro_locales' and
  4701 `unfold_locales'; see below.
  4702 
  4703 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4704 provide backward reasoning on locales predicates.  The methods are
  4705 aware of interpretations and discharge corresponding goals.
  4706 `intro_locales' is less aggressive then `unfold_locales' and does not
  4707 unfold predicates to assumptions.
  4708 
  4709 * Isar/locales: the order in which locale fragments are accumulated
  4710 has changed.  This enables to override declarations from fragments due
  4711 to interpretations -- for example, unwanted simp rules.
  4712 
  4713 * Isar/locales: interpretation in theories and proof contexts has been
  4714 extended.  One may now specify (and prove) equations, which are
  4715 unfolded in interpreted theorems.  This is useful for replacing
  4716 defined concepts (constants depending on locale parameters) by
  4717 concepts already existing in the target context.  Example:
  4718 
  4719   interpretation partial_order ["op <= :: [int, int] => bool"]
  4720     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4721 
  4722 Typically, the constant `partial_order.less' is created by a
  4723 definition specification element in the context of locale
  4724 partial_order.
  4725 
  4726 * Method "induct": improved internal context management to support
  4727 local fixes and defines on-the-fly. Thus explicit meta-level
  4728 connectives !!  and ==> are rarely required anymore in inductive goals
  4729 (using object-logic connectives for this purpose has been long
  4730 obsolete anyway). Common proof patterns are explained in
  4731 src/HOL/Induct/Common_Patterns.thy, see also
  4732 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4733 examples.
  4734 
  4735 * Method "induct": improved handling of simultaneous goals. Instead of
  4736 introducing object-level conjunction, the statement is now split into
  4737 several conclusions, while the corresponding symbolic cases are nested
  4738 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4739 see src/HOL/Induct/Common_Patterns.thy, for example.
  4740 
  4741 * Method "induct": mutual induction rules are now specified as a list
  4742 of rule sharing the same induction cases. HOL packages usually provide
  4743 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4744 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4745 mutual induction rules differently, i.e. like this:
  4746 
  4747   (induct rule: foo_bar.inducts)
  4748   (induct set: foo bar)
  4749   (induct pred: foo bar)
  4750   (induct type: foo bar)
  4751 
  4752 The ML function ProjectRule.projections turns old-style rules into the
  4753 new format.
  4754 
  4755 * Method "coinduct": dual of induction, see
  4756 src/HOL/Library/Coinductive_List.thy for various examples.
  4757 
  4758 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4759 considered a legacy feature.
  4760 
  4761 * Attribute "symmetric" produces result with standardized schematic
  4762 variables (index 0).  Potential INCOMPATIBILITY.
  4763 
  4764 * Simplifier: by default the simplifier trace only shows top level
  4765 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4766 default. Thus there is less danger of being flooded by the trace. The
  4767 trace indicates where parts have been suppressed.
  4768   
  4769 * Provers/classical: removed obsolete classical version of elim_format
  4770 attribute; classical elim/dest rules are now treated uniformly when
  4771 manipulating the claset.
  4772 
  4773 * Provers/classical: stricter checks to ensure that supplied intro,
  4774 dest and elim rules are well-formed; dest and elim rules must have at
  4775 least one premise.
  4776 
  4777 * Provers/classical: attributes dest/elim/intro take an optional
  4778 weight argument for the rule (just as the Pure versions).  Weights are
  4779 ignored by automated tools, but determine the search order of single
  4780 rule steps.
  4781 
  4782 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4783 where the body does not mention the bound variable.  Note that dummy
  4784 patterns implicitly depend on their context of bounds, which makes
  4785 "{_. _}" match any set comprehension as expected.  Potential
  4786 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4787 constant "_idtdummy" in the binding position.
  4788 
  4789 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4790 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4791 for example "A -> B" => "Pi A (%_. B)".
  4792 
  4793 * Pure: 'class_deps' command visualizes the subclass relation, using
  4794 the graph browser tool.
  4795 
  4796 * Pure: 'print_theory' now suppresses certain internal declarations by
  4797 default; use '!' option for full details.
  4798 
  4799 
  4800 *** HOL ***
  4801 
  4802 * Method "metis" proves goals by applying the Metis general-purpose
  4803 resolution prover (see also http://gilith.com/software/metis/).
  4804 Examples are in the directory MetisExamples.  WARNING: the
  4805 Isabelle/HOL-Metis integration does not yet work properly with
  4806 multi-threading.
  4807   
  4808 * Command 'sledgehammer' invokes external automatic theorem provers as
  4809 background processes.  It generates calls to the "metis" method if
  4810 successful. These can be pasted into the proof.  Users do not have to
  4811 wait for the automatic provers to return.  WARNING: does not really
  4812 work with multi-threading.
  4813 
  4814 * New "auto_quickcheck" feature tests outermost goal statements for
  4815 potential counter-examples.  Controlled by ML references
  4816 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4817 5000 milliseconds).  Fails silently if statements is outside of
  4818 executable fragment, or any other codgenerator problem occurs.
  4819 
  4820 * New constant "undefined" with axiom "undefined x = undefined".
  4821 
  4822 * Added class "HOL.eq", allowing for code generation with polymorphic
  4823 equality.
  4824 
  4825 * Some renaming of class constants due to canonical name prefixing in
  4826 the new 'class' package:
  4827 
  4828     HOL.abs ~> HOL.abs_class.abs
  4829     HOL.divide ~> HOL.divide_class.divide
  4830     0 ~> HOL.zero_class.zero
  4831     1 ~> HOL.one_class.one
  4832     op + ~> HOL.plus_class.plus
  4833     op - ~> HOL.minus_class.minus
  4834     uminus ~> HOL.minus_class.uminus
  4835     op * ~> HOL.times_class.times
  4836     op < ~> HOL.ord_class.less
  4837     op <= > HOL.ord_class.less_eq
  4838     Nat.power ~> Power.power_class.power
  4839     Nat.size ~> Nat.size_class.size
  4840     Numeral.number_of ~> Numeral.number_class.number_of
  4841     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4842     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4843     Orderings.min ~> Orderings.ord_class.min
  4844     Orderings.max ~> Orderings.ord_class.max
  4845     Divides.op div ~> Divides.div_class.div
  4846     Divides.op mod ~> Divides.div_class.mod
  4847     Divides.op dvd ~> Divides.div_class.dvd
  4848 
  4849 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4850 
  4851 a) User-defined constants using any of the names "plus", "minus",
  4852 "times", "less" or "less_eq". The standard syntax translations for
  4853 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4854 names.
  4855 
  4856 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4857 INCOMPATIBILITY: use more specific names.
  4858 
  4859 c) Permutative equations (e.g. "a + b = b + a")
  4860 Since the change of names also changes the order of terms, permutative
  4861 rewrite rules may get applied in a different order. Experience shows
  4862 that this is rarely the case (only two adaptions in the whole Isabelle
  4863 distribution).  INCOMPATIBILITY: rewrite proofs
  4864 
  4865 d) ML code directly refering to constant names
  4866 This in general only affects hand-written proof tactics, simprocs and
  4867 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4868 Consider using @{const_name} antiquotation.
  4869 
  4870 * New class "default" with associated constant "default".
  4871 
  4872 * Function "sgn" is now overloaded and available on int, real, complex
  4873 (and other numeric types), using class "sgn".  Two possible defs of
  4874 sgn are given as equational assumptions in the classes sgn_if and
  4875 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4876 INCOMPATIBILITY.
  4877 
  4878 * Locale "partial_order" now unified with class "order" (cf. theory
  4879 Orderings), added parameter "less".  INCOMPATIBILITY.
  4880 
  4881 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4882 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4883 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4884 
  4885 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4886 changed order of proof goals in instance proofs.
  4887 
  4888 * The transitivity reasoner for partial and linear orders is set up
  4889 for classes "order" and "linorder".  Instances of the reasoner are available
  4890 in all contexts importing or interpreting the corresponding locales.
  4891 Method "order" invokes the reasoner separately; the reasoner
  4892 is also integrated with the Simplifier as a solver.  Diagnostic
  4893 command 'print_orders' shows the available instances of the reasoner
  4894 in the current context.
  4895 
  4896 * Localized monotonicity predicate in theory "Orderings"; integrated
  4897 lemmas max_of_mono and min_of_mono with this predicate.
  4898 INCOMPATIBILITY.
  4899 
  4900 * Formulation of theorem "dense" changed slightly due to integration
  4901 with new class dense_linear_order.
  4902 
  4903 * Uniform lattice theory development in HOL.
  4904 
  4905     constants "meet" and "join" now named "inf" and "sup"
  4906     constant "Meet" now named "Inf"
  4907 
  4908     classes "meet_semilorder" and "join_semilorder" now named
  4909       "lower_semilattice" and "upper_semilattice"
  4910     class "lorder" now named "lattice"
  4911     class "comp_lat" now named "complete_lattice"
  4912 
  4913     Instantiation of lattice classes allows explicit definitions
  4914     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4915 
  4916   INCOMPATIBILITY.  Theorem renames:
  4917 
  4918     meet_left_le            ~> inf_le1
  4919     meet_right_le           ~> inf_le2
  4920     join_left_le            ~> sup_ge1
  4921     join_right_le           ~> sup_ge2
  4922     meet_join_le            ~> inf_sup_ord
  4923     le_meetI                ~> le_infI
  4924     join_leI                ~> le_supI
  4925     le_meet                 ~> le_inf_iff
  4926     le_join                 ~> ge_sup_conv
  4927     meet_idempotent         ~> inf_idem
  4928     join_idempotent         ~> sup_idem
  4929     meet_comm               ~> inf_commute
  4930     join_comm               ~> sup_commute
  4931     meet_leI1               ~> le_infI1
  4932     meet_leI2               ~> le_infI2
  4933     le_joinI1               ~> le_supI1
  4934     le_joinI2               ~> le_supI2
  4935     meet_assoc              ~> inf_assoc
  4936     join_assoc              ~> sup_assoc
  4937     meet_left_comm          ~> inf_left_commute
  4938     meet_left_idempotent    ~> inf_left_idem
  4939     join_left_comm          ~> sup_left_commute
  4940     join_left_idempotent    ~> sup_left_idem
  4941     meet_aci                ~> inf_aci
  4942     join_aci                ~> sup_aci
  4943     le_def_meet             ~> le_iff_inf
  4944     le_def_join             ~> le_iff_sup
  4945     join_absorp2            ~> sup_absorb2
  4946     join_absorp1            ~> sup_absorb1
  4947     meet_absorp1            ~> inf_absorb1
  4948     meet_absorp2            ~> inf_absorb2
  4949     meet_join_absorp        ~> inf_sup_absorb
  4950     join_meet_absorp        ~> sup_inf_absorb
  4951     distrib_join_le         ~> distrib_sup_le
  4952     distrib_meet_le         ~> distrib_inf_le
  4953 
  4954     add_meet_distrib_left   ~> add_inf_distrib_left
  4955     add_join_distrib_left   ~> add_sup_distrib_left
  4956     is_join_neg_meet        ~> is_join_neg_inf
  4957     is_meet_neg_join        ~> is_meet_neg_sup
  4958     add_meet_distrib_right  ~> add_inf_distrib_right
  4959     add_join_distrib_right  ~> add_sup_distrib_right
  4960     add_meet_join_distribs  ~> add_sup_inf_distribs
  4961     join_eq_neg_meet        ~> sup_eq_neg_inf
  4962     meet_eq_neg_join        ~> inf_eq_neg_sup
  4963     add_eq_meet_join        ~> add_eq_inf_sup
  4964     meet_0_imp_0            ~> inf_0_imp_0
  4965     join_0_imp_0            ~> sup_0_imp_0
  4966     meet_0_eq_0             ~> inf_0_eq_0
  4967     join_0_eq_0             ~> sup_0_eq_0
  4968     neg_meet_eq_join        ~> neg_inf_eq_sup
  4969     neg_join_eq_meet        ~> neg_sup_eq_inf
  4970     join_eq_if              ~> sup_eq_if
  4971 
  4972     mono_meet               ~> mono_inf
  4973     mono_join               ~> mono_sup
  4974     meet_bool_eq            ~> inf_bool_eq
  4975     join_bool_eq            ~> sup_bool_eq
  4976     meet_fun_eq             ~> inf_fun_eq
  4977     join_fun_eq             ~> sup_fun_eq
  4978     meet_set_eq             ~> inf_set_eq
  4979     join_set_eq             ~> sup_set_eq
  4980     meet1_iff               ~> inf1_iff
  4981     meet2_iff               ~> inf2_iff
  4982     meet1I                  ~> inf1I
  4983     meet2I                  ~> inf2I
  4984     meet1D1                 ~> inf1D1
  4985     meet2D1                 ~> inf2D1
  4986     meet1D2                 ~> inf1D2
  4987     meet2D2                 ~> inf2D2
  4988     meet1E                  ~> inf1E
  4989     meet2E                  ~> inf2E
  4990     join1_iff               ~> sup1_iff
  4991     join2_iff               ~> sup2_iff
  4992     join1I1                 ~> sup1I1
  4993     join2I1                 ~> sup2I1
  4994     join1I1                 ~> sup1I1
  4995     join2I2                 ~> sup1I2
  4996     join1CI                 ~> sup1CI
  4997     join2CI                 ~> sup2CI
  4998     join1E                  ~> sup1E
  4999     join2E                  ~> sup2E
  5000 
  5001     is_meet_Meet            ~> is_meet_Inf
  5002     Meet_bool_def           ~> Inf_bool_def
  5003     Meet_fun_def            ~> Inf_fun_def
  5004     Meet_greatest           ~> Inf_greatest
  5005     Meet_lower              ~> Inf_lower
  5006     Meet_set_def            ~> Inf_set_def
  5007 
  5008     Sup_def                 ~> Sup_Inf
  5009     Sup_bool_eq             ~> Sup_bool_def
  5010     Sup_fun_eq              ~> Sup_fun_def
  5011     Sup_set_eq              ~> Sup_set_def
  5012 
  5013     listsp_meetI            ~> listsp_infI
  5014     listsp_meet_eq          ~> listsp_inf_eq
  5015 
  5016     meet_min                ~> inf_min
  5017     join_max                ~> sup_max
  5018 
  5019 * Added syntactic class "size"; overloaded constant "size" now has
  5020 type "'a::size ==> bool"
  5021 
  5022 * Internal reorganisation of `size' of datatypes: size theorems
  5023 "foo.size" are no longer subsumed by "foo.simps" (but are still
  5024 simplification rules by default!); theorems "prod.size" now named
  5025 "*.size".
  5026 
  5027 * Class "div" now inherits from class "times" rather than "type".
  5028 INCOMPATIBILITY.
  5029 
  5030 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  5031 Linorder etc.  have disappeared; operations defined in terms of
  5032 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  5033 
  5034 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  5035 
  5036 * HOL-Word: New extensive library and type for generic, fixed size
  5037 machine words, with arithmetic, bit-wise, shifting and rotating
  5038 operations, reflection into int, nat, and bool lists, automation for
  5039 linear arithmetic (by automatic reflection into nat or int), including
  5040 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  5041 arithmetic type classes, supporting automatic simplification of
  5042 numerals on all operations.
  5043 
  5044 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  5045 
  5046 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  5047 
  5048 * Code generator library theories:
  5049   - Code_Integer represents HOL integers by big integer literals in target
  5050     languages.
  5051   - Code_Char represents HOL characters by character literals in target
  5052     languages.
  5053   - Code_Char_chr like Code_Char, but also offers treatment of character
  5054     codes; includes Code_Integer.
  5055   - Executable_Set allows to generate code for finite sets using lists.
  5056   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  5057     denominator).
  5058   - Executable_Real implements a subset of real numbers, namly those
  5059     representable by rational numbers.
  5060   - Efficient_Nat implements natural numbers by integers, which in general will
  5061     result in higher efficency; pattern matching with 0/Suc is eliminated;
  5062     includes Code_Integer.
  5063   - Code_Index provides an additional datatype index which is mapped to
  5064     target-language built-in integers.
  5065   - Code_Message provides an additional datatype message_string which is isomorphic to
  5066     strings; messages are mapped to target-language strings.
  5067 
  5068 * New package for inductive predicates
  5069 
  5070   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  5071 
  5072     inductive
  5073       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5074       for z_1 :: U_1 and ... and z_n :: U_m
  5075     where
  5076       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5077     | ...
  5078 
  5079   with full support for type-inference, rather than
  5080 
  5081     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5082 
  5083     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5084     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5085 
  5086     inductive "s z_1 ... z_m"
  5087     intros
  5088       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5089       ...
  5090 
  5091   For backward compatibility, there is a wrapper allowing inductive
  5092   sets to be defined with the new package via
  5093 
  5094     inductive_set
  5095       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5096       for z_1 :: U_1 and ... and z_n :: U_m
  5097     where
  5098       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  5099     | ...
  5100 
  5101   or
  5102 
  5103     inductive_set
  5104       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  5105       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  5106       for z_1 :: U_1 and ... and z_n :: U_m
  5107     where
  5108       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  5109     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  5110     | ...
  5111 
  5112   if the additional syntax "p ..." is required.
  5113 
  5114   Numerous examples can be found in the subdirectories src/HOL/Auth,
  5115   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  5116 
  5117   INCOMPATIBILITIES:
  5118 
  5119   - Since declaration and definition of inductive sets or predicates
  5120     is no longer separated, abbreviations involving the newly
  5121     introduced sets or predicates must be specified together with the
  5122     introduction rules after the 'where' keyword (see above), rather
  5123     than before the actual inductive definition.
  5124 
  5125   - The variables in induction and elimination rules are now
  5126     quantified in the order of their occurrence in the introduction
  5127     rules, rather than in alphabetical order. Since this may break
  5128     some proofs, these proofs either have to be repaired, e.g. by
  5129     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  5130     statements of the form
  5131 
  5132       case (rule_i a_i_1 ... a_i_{k_i})
  5133 
  5134     or the old order of quantification has to be restored by explicitly adding
  5135     meta-level quantifiers in the introduction rules, i.e.
  5136 
  5137       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  5138 
  5139   - The format of the elimination rules is now
  5140 
  5141       p z_1 ... z_m x_1 ... x_n ==>
  5142         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5143         ==> ... ==> P
  5144 
  5145     for predicates and
  5146 
  5147       (x_1, ..., x_n) : s z_1 ... z_m ==>
  5148         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  5149         ==> ... ==> P
  5150 
  5151     for sets rather than
  5152 
  5153       x : s z_1 ... z_m ==>
  5154         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  5155         ==> ... ==> P
  5156 
  5157     This may require terms in goals to be expanded to n-tuples
  5158     (e.g. using case_tac or simplification with the split_paired_all
  5159     rule) before the above elimination rule is applicable.
  5160 
  5161   - The elimination or case analysis rules for (mutually) inductive
  5162     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  5163     list of rules "p_1_..._p_k.elims" is no longer available.
  5164 
  5165 * New package "function"/"fun" for general recursive functions,
  5166 supporting mutual and nested recursion, definitions in local contexts,
  5167 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  5168 for small examples, and the separate tutorial on the function
  5169 package. The old recdef "package" is still available as before, but
  5170 users are encouraged to use the new package.
  5171 
  5172 * Method "lexicographic_order" automatically synthesizes termination
  5173 relations as lexicographic combinations of size measures. 
  5174 
  5175 * Case-expressions allow arbitrary constructor-patterns (including
  5176 "_") and take their order into account, like in functional
  5177 programming.  Internally, this is translated into nested
  5178 case-expressions; missing cases are added and mapped to the predefined
  5179 constant "undefined". In complicated cases printing may no longer show
  5180 the original input but the internal form. Lambda-abstractions allow
  5181 the same form of pattern matching: "% pat1 => e1 | ..." is an
  5182 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  5183 variable.
  5184 
  5185 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  5186 is an abbreviation for "of_nat :: nat => int". The simplification
  5187 rules for "of_nat" have been changed to work like "int" did
  5188 previously.  Potential INCOMPATIBILITY:
  5189   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  5190   - of_nat_diff and of_nat_mult are no longer default simp rules
  5191 
  5192 * Method "algebra" solves polynomial equations over (semi)rings using
  5193 Groebner bases. The (semi)ring structure is defined by locales and the
  5194 tool setup depends on that generic context. Installing the method for
  5195 a specific type involves instantiating the locale and possibly adding
  5196 declarations for computation on the coefficients.  The method is
  5197 already instantiated for natural numbers and for the axiomatic class
  5198 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  5199 CALCULEMUS 2007 for the general principles underlying this
  5200 architecture of context-aware proof-tools.
  5201 
  5202 * Method "ferrack" implements quantifier elimination over
  5203 special-purpose dense linear orders using locales (analogous to
  5204 "algebra"). The method is already installed for class
  5205 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  5206 rat, etc.
  5207 
  5208 * Former constant "List.op @" now named "List.append".  Use ML
  5209 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  5210 circumvent possible incompatibilities when working on ML level.
  5211 
  5212 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  5213 
  5214 * New function listsum :: 'a list => 'a for arbitrary monoids.
  5215 Special syntax: "SUM x <- xs. f x" (and latex variants)
  5216 
  5217 * New syntax for Haskell-like list comprehension (input only), eg.
  5218 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  5219 
  5220 * The special syntax for function "filter" has changed from [x :
  5221 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  5222 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  5223 
  5224 * [a..b] is now defined for arbitrary linear orders.  It used to be
  5225 defined on nat only, as an abbreviation for [a..<Suc b]
  5226 INCOMPATIBILITY.
  5227 
  5228 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  5229 
  5230 * New functions "sorted" and "sort" in src/HOL/List.thy.
  5231 
  5232 * New lemma collection field_simps (an extension of ring_simps) for
  5233 manipulating (in)equations involving division. Multiplies with all
  5234 denominators that can be proved to be non-zero (in equations) or
  5235 positive/negative (in inequations).
  5236 
  5237 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  5238 have been improved and renamed to ring_simps, group_simps and
  5239 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  5240 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  5241 
  5242 * Theory Library/Commutative_Ring: switched from recdef to function
  5243 package; constants add, mul, pow now curried.  Infix syntax for
  5244 algebraic operations.
  5245 
  5246 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  5247 INCOMPATIBILITY.
  5248 
  5249 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  5250 INCOMPATIBILITY.
  5251 
  5252 * HOL/records: generalised field-update to take a function on the
  5253 field rather than the new value: r(|A := x|) is translated to A_update
  5254 (K x) r The K-combinator that is internally used is called K_record.
  5255 INCOMPATIBILITY: Usage of the plain update functions has to be
  5256 adapted.
  5257  
  5258 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  5259 * x = 0, which are required for a semiring.  Richer structures do not
  5260 inherit from semiring_0 anymore, because this property is a theorem
  5261 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  5262 there is more to prove, but this is mostly trivial.
  5263 
  5264 * Class "recpower" is generalized to arbitrary monoids, not just
  5265 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  5266 commutativity or semiring properties additionally.
  5267 
  5268 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  5269 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  5270 better use 'abbreviation'.
  5271 
  5272 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  5273 
  5274 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  5275 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  5276 significant changes for setting up numeral syntax for types:
  5277   - New constants Numeral.pred and Numeral.succ instead
  5278       of former Numeral.bin_pred and Numeral.bin_succ.
  5279   - Use integer operations instead of bin_add, bin_mult and so on.
  5280   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  5281   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  5282 
  5283 See src/HOL/Integ/IntArith.thy for an example setup.
  5284 
  5285 * Command 'normal_form' computes the normal form of a term that may
  5286 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  5287 produces ``[b, c, a]'' (without proof).  This command is suitable for
  5288 heavy-duty computations because the functions are compiled to ML
  5289 first.  Correspondingly, a method "normalization" is provided.  See
  5290 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  5291 
  5292 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  5293 25 like -->); output depends on the "iff" print_mode, the default is
  5294 "A = B" (with priority 50).
  5295 
  5296 * Relations less (<) and less_eq (<=) are also available on type bool.
  5297 Modified syntax to disallow nesting without explicit parentheses,
  5298 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  5299 INCOMPATIBILITY.
  5300 
  5301 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  5302 
  5303 * Relation composition operator "op O" now has precedence 75 and binds
  5304 stronger than union and intersection. INCOMPATIBILITY.
  5305 
  5306 * The old set interval syntax "{m..n(}" (and relatives) has been
  5307 removed.  Use "{m..<n}" (and relatives) instead.
  5308 
  5309 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  5310 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  5311 ``declare [[simproc del: neq]]''.
  5312 
  5313 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  5314 True/False.
  5315 
  5316 * Theorem Cons_eq_map_conv no longer declared as "simp".
  5317 
  5318 * Theorem setsum_mult renamed to setsum_right_distrib.
  5319 
  5320 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  5321 ``rule'' method.
  5322 
  5323 * Reimplemented methods "sat" and "satx", with several improvements:
  5324 goals no longer need to be stated as "<prems> ==> False", equivalences
  5325 (i.e. "=" on type bool) are handled, variable names of the form
  5326 "lit_<n>" are no longer reserved, significant speedup.
  5327 
  5328 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  5329 zChaff is still supported as well.
  5330 
  5331 * 'inductive' and 'datatype': provide projections of mutual rules,
  5332 bundled as foo_bar.inducts;
  5333 
  5334 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  5335 Library.
  5336 
  5337 * Library: moved theory Accessible_Part to main HOL.
  5338 
  5339 * Library: added theory Coinductive_List of potentially infinite lists
  5340 as greatest fixed-point.
  5341 
  5342 * Library: added theory AssocList which implements (finite) maps as
  5343 association lists.
  5344 
  5345 * Method "evaluation" solves goals (i.e. a boolean expression)
  5346 efficiently by compiling it to ML.  The goal is "proved" (via an
  5347 oracle) if it evaluates to True.
  5348 
  5349 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  5350 also when invoked by the simplifier.  This results in the Simplifier
  5351 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  5352 Configuration option fast_arith_split_limit=0 recovers the old
  5353 behavior.
  5354 
  5355 * Support for hex (0x20) and binary (0b1001) numerals.
  5356 
  5357 * New method: reify eqs (t), where eqs are equations for an
  5358 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  5359 parameter, computes a term s::'b and a list xs::'a list and proves the
  5360 theorem I xs s = t. This is also known as reification or quoting. The
  5361 resulting theorem is applied to the subgoal to substitute t with I xs
  5362 s.  If t is omitted, the subgoal itself is reified.
  5363 
  5364 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  5365 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  5366 where f is supposed to be a computable function (in the sense of code
  5367 generattion). The method uses reify to compute s and xs as above then
  5368 applies corr_thm and uses normalization by evaluation to "prove" f s =
  5369 r and finally gets the theorem t = r, which is again applied to the
  5370 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  5371 
  5372 * Reflection: Automatic reification now handels binding, an example is
  5373 available in src/HOL/ex/ReflectionEx.thy
  5374 
  5375 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  5376 command 'statespace' that is similar to 'record', but introduces an
  5377 abstract specification based on the locale infrastructure instead of
  5378 HOL types.  This leads to extra flexibility in composing state spaces,
  5379 in particular multiple inheritance and renaming of components.
  5380 
  5381 
  5382 *** HOL-Complex ***
  5383 
  5384 * Hyperreal: Functions root and sqrt are now defined on negative real
  5385 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  5386 Nonnegativity side conditions have been removed from many lemmas, so
  5387 that more subgoals may now be solved by simplification; potential
  5388 INCOMPATIBILITY.
  5389 
  5390 * Real: new type classes formalize real normed vector spaces and
  5391 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  5392 and norm :: 'a => real.
  5393 
  5394 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  5395 reals into other types. The overloaded constant Reals :: 'a set is now
  5396 defined as range of_real; potential INCOMPATIBILITY.
  5397 
  5398 * Real: proper support for ML code generation, including 'quickcheck'.
  5399 Reals are implemented as arbitrary precision rationals.
  5400 
  5401 * Hyperreal: Several constants that previously worked only for the
  5402 reals have been generalized, so they now work over arbitrary vector
  5403 spaces. Type annotations may need to be added in some cases; potential
  5404 INCOMPATIBILITY.
  5405 
  5406   Infinitesimal  :: ('a::real_normed_vector) star set
  5407   HFinite        :: ('a::real_normed_vector) star set
  5408   HInfinite      :: ('a::real_normed_vector) star set
  5409   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5410   monad          :: ('a::real_normed_vector) star => 'a star set
  5411   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5412   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5413   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5414   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5415   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5416   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5417   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5418   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5419   sgn            :: 'a::real_normed_vector => 'a
  5420   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5421 
  5422 * Complex: Some complex-specific constants are now abbreviations for
  5423 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5424 hnorm.  Other constants have been entirely removed in favor of the
  5425 polymorphic versions (INCOMPATIBILITY):
  5426 
  5427   approx        <-- capprox
  5428   HFinite       <-- CFinite
  5429   HInfinite     <-- CInfinite
  5430   Infinitesimal <-- CInfinitesimal
  5431   monad         <-- cmonad
  5432   galaxy        <-- cgalaxy
  5433   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5434   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5435   (ns)deriv     <-- (ns)cderiv
  5436 
  5437 
  5438 *** HOL-Algebra ***
  5439 
  5440 * Formalisation of ideals and the quotient construction over rings.
  5441 
  5442 * Order and lattice theory no longer based on records.
  5443 INCOMPATIBILITY.
  5444 
  5445 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5446 greatest_closed.  INCOMPATIBILITY.
  5447 
  5448 * Method algebra is now set up via an attribute.  For examples see
  5449 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5450 of algebraic structures.
  5451 
  5452 * Renamed theory CRing to Ring.
  5453 
  5454 
  5455 *** HOL-Nominal ***
  5456 
  5457 * Substantial, yet incomplete support for nominal datatypes (binding
  5458 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5459 src/HOL/Nominal/Examples.  Prospective users should consult
  5460 http://isabelle.in.tum.de/nominal/
  5461 
  5462 
  5463 *** ML ***
  5464 
  5465 * ML basics: just one true type int, which coincides with IntInf.int
  5466 (even on SML/NJ).
  5467 
  5468 * ML within Isar: antiquotations allow to embed statically-checked
  5469 formal entities in the source, referring to the context available at
  5470 compile-time.  For example:
  5471 
  5472 ML {* @{sort "{zero,one}"} *}
  5473 ML {* @{typ "'a => 'b"} *}
  5474 ML {* @{term "%x. x"} *}
  5475 ML {* @{prop "x == y"} *}
  5476 ML {* @{ctyp "'a => 'b"} *}
  5477 ML {* @{cterm "%x. x"} *}
  5478 ML {* @{cprop "x == y"} *}
  5479 ML {* @{thm asm_rl} *}
  5480 ML {* @{thms asm_rl} *}
  5481 ML {* @{type_name c} *}
  5482 ML {* @{type_syntax c} *}
  5483 ML {* @{const_name c} *}
  5484 ML {* @{const_syntax c} *}
  5485 ML {* @{context} *}
  5486 ML {* @{theory} *}
  5487 ML {* @{theory Pure} *}
  5488 ML {* @{theory_ref} *}
  5489 ML {* @{theory_ref Pure} *}
  5490 ML {* @{simpset} *}
  5491 ML {* @{claset} *}
  5492 ML {* @{clasimpset} *}
  5493 
  5494 The same works for sources being ``used'' within an Isar context.
  5495 
  5496 * ML in Isar: improved error reporting; extra verbosity with
  5497 ML_Context.trace enabled.
  5498 
  5499 * Pure/General/table.ML: the join operations now works via exceptions
  5500 DUP/SAME instead of type option. This is simpler in simple cases, and
  5501 admits slightly more efficient complex applications.
  5502 
  5503 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5504 use Context.generic instead of just theory.
  5505 
  5506 * Pure: datatype Context.generic joins theory/Proof.context and
  5507 provides some facilities for code that works in either kind of
  5508 context, notably GenericDataFun for uniform theory and proof data.
  5509 
  5510 * Pure: simplified internal attribute type, which is now always
  5511 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5512 local (Proof.context) attributes have been discontinued, while
  5513 minimizing code duplication. Thm.rule_attribute and
  5514 Thm.declaration_attribute build canonical attributes; see also structure
  5515 Context for further operations on Context.generic, notably
  5516 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5517 declarations and definitions.
  5518 
  5519 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5520 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5521 init only required for impure data. INCOMPATIBILITY: empty really need
  5522 to be empty (no dependencies on theory content!)
  5523 
  5524 * Pure/kernel: consts certification ignores sort constraints given in
  5525 signature declarations. (This information is not relevant to the
  5526 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5527 potential INCOMPATIBILITY.
  5528 
  5529 * Pure: axiomatic type classes are now purely definitional, with
  5530 explicit proofs of class axioms and super class relations performed
  5531 internally. See Pure/axclass.ML for the main internal interfaces --
  5532 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5533 AxClass.axiomatize_class/classrel/arity supersede
  5534 Sign.add_classes/classrel/arities.
  5535 
  5536 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5537 global/local versions on theory vs. Proof.context have been
  5538 discontinued; Attrib.syntax and Method.syntax have been adapted
  5539 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5540 attributes, methods, etc.
  5541 
  5542 * Pure: several functions of signature "... -> theory -> theory * ..."
  5543 have been reoriented to "... -> theory -> ... * theory" in order to
  5544 allow natural usage in combination with the ||>, ||>>, |-> and
  5545 fold_map combinators.
  5546 
  5547 * Pure: official theorem names (closed derivations) and additional
  5548 comments (tags) are now strictly separate.  Name hints -- which are
  5549 maintained as tags -- may be attached any time without affecting the
  5550 derivation.
  5551 
  5552 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5553 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5554 achieve the old behaviour.
  5555 
  5556 * Pure: the "Goal" constant is now called "prop", supporting a
  5557 slightly more general idea of ``protecting'' meta-level rule
  5558 statements.
  5559 
  5560 * Pure: Logic.(un)varify only works in a global context, which is now
  5561 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5562 Logic.legacy_(un)varify as temporary workaround.
  5563 
  5564 * Pure: structure Name provides scalable operations for generating
  5565 internal variable names, notably Name.variants etc.  This replaces
  5566 some popular functions from term.ML:
  5567 
  5568   Term.variant		->  Name.variant
  5569   Term.variantlist	->  Name.variant_list
  5570   Term.invent_names	->  Name.invent_list
  5571 
  5572 Note that low-level renaming rarely occurs in new code -- operations
  5573 from structure Variable are used instead (see below).
  5574 
  5575 * Pure: structure Variable provides fundamental operations for proper
  5576 treatment of fixed/schematic variables in a context.  For example,
  5577 Variable.import introduces fixes for schematics of given facts and
  5578 Variable.export reverses the effect (up to renaming) -- this replaces
  5579 various freeze_thaw operations.
  5580 
  5581 * Pure: structure Goal provides simple interfaces for
  5582 init/conclude/finish and tactical prove operations (replacing former
  5583 Tactic.prove).  Goal.prove is the canonical way to prove results
  5584 within a given context; Goal.prove_global is a degraded version for
  5585 theory level goals, including a global Drule.standard.  Note that
  5586 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5587 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5588 in a locale context).
  5589 
  5590 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5591 and type checking (Syntax.check_term etc.), with common combinations
  5592 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5593 which are considered legacy and await removal.
  5594 
  5595 * Pure/Syntax: generic interfaces for type unchecking
  5596 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5597 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5598 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5599 available for convenience, but refer to the very same operations using
  5600 a mere theory instead of a full context.
  5601 
  5602 * Isar: simplified treatment of user-level errors, using exception
  5603 ERROR of string uniformly.  Function error now merely raises ERROR,
  5604 without any side effect on output channels.  The Isar toplevel takes
  5605 care of proper display of ERROR exceptions.  ML code may use plain
  5606 handle/can/try; cat_error may be used to concatenate errors like this:
  5607 
  5608   ... handle ERROR msg => cat_error msg "..."
  5609 
  5610 Toplevel ML code (run directly or through the Isar toplevel) may be
  5611 embedded into the Isar toplevel with exception display/debug like
  5612 this:
  5613 
  5614   Isar.toplevel (fn () => ...)
  5615 
  5616 INCOMPATIBILITY, removed special transform_error facilities, removed
  5617 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5618 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5619 -- use plain ERROR instead.
  5620 
  5621 * Isar: theory setup now has type (theory -> theory), instead of a
  5622 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5623 
  5624 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5625 ProofContext.debug/verbose flags.
  5626 
  5627 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5628 theory before entering a proof state.  Transactions now always see a
  5629 quasi-functional intermediate checkpoint, both in interactive and
  5630 batch mode.
  5631 
  5632 * Isar: simplified interfaces for outer syntax.  Renamed
  5633 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5634 OuterSyntax.add_parsers -- this functionality is now included in
  5635 OuterSyntax.command etc.  INCOMPATIBILITY.
  5636 
  5637 * Simplifier: the simpset of a running simplification process now
  5638 contains a proof context (cf. Simplifier.the_context), which is the
  5639 very context that the initial simpset has been retrieved from (by
  5640 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5641 (solver, looper etc.) may depend on arbitrary proof data.
  5642 
  5643 * Simplifier.inherit_context inherits the proof context (plus the
  5644 local bounds) of the current simplification process; any simproc
  5645 etc. that calls the Simplifier recursively should do this!  Removed
  5646 former Simplifier.inherit_bounds, which is already included here --
  5647 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5648 specify an explicit context using Simplifier.context/theory_context.
  5649 
  5650 * Simplifier/Classical Reasoner: more abstract interfaces
  5651 change_simpset/claset for modifying the simpset/claset reference of a
  5652 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5653 INCOMPATIBILITY.
  5654 
  5655 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5656 "Trueprop" etc.
  5657 
  5658 
  5659 *** System ***
  5660 
  5661 * settings: the default heap location within ISABELLE_HOME_USER now
  5662 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5663 Isabelle installations.
  5664 
  5665 * isabelle-process: option -S (secure mode) disables some critical
  5666 operations, notably runtime compilation and evaluation of ML source
  5667 code.
  5668 
  5669 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5670 
  5671 * Support for parallel execution, using native multicore support of
  5672 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5673 independent theories, according to the given theory header
  5674 specifications. The maximum number of worker threads is specified via
  5675 usedir option -M or the "max-threads" setting in Proof General. A
  5676 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5677 to 6 on a 8-core machine.  User-code needs to observe certain
  5678 guidelines for thread-safe programming, see appendix A in the Isar
  5679 Implementation manual.
  5680 
  5681 
  5682 
  5683 New in Isabelle2005 (October 2005)
  5684 ----------------------------------
  5685 
  5686 *** General ***
  5687 
  5688 * Theory headers: the new header syntax for Isar theories is
  5689 
  5690   theory <name>
  5691   imports <theory1> ... <theoryN>
  5692   uses <file1> ... <fileM>
  5693   begin
  5694 
  5695 where the 'uses' part is optional.  The previous syntax
  5696 
  5697   theory <name> = <theory1> + ... + <theoryN>:
  5698 
  5699 will disappear in the next release.  Use isatool fixheaders to convert
  5700 existing theory files.  Note that there is no change in ancient
  5701 non-Isar theories now, but these will disappear soon.
  5702 
  5703 * Theory loader: parent theories can now also be referred to via
  5704 relative and absolute paths.
  5705 
  5706 * Command 'find_theorems' searches for a list of criteria instead of a
  5707 list of constants. Known criteria are: intro, elim, dest, name:string,
  5708 simp:term, and any term. Criteria can be preceded by '-' to select
  5709 theorems that do not match. Intro, elim, dest select theorems that
  5710 match the current goal, name:s selects theorems whose fully qualified
  5711 name contain s, and simp:term selects all simplification rules whose
  5712 lhs match term.  Any other term is interpreted as pattern and selects
  5713 all theorems matching the pattern. Available in ProofGeneral under
  5714 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5715 
  5716   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5717 
  5718 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5719 matching the current goal as introduction rule and not having "HOL."
  5720 in their name (i.e. not being defined in theory HOL).
  5721 
  5722 * Command 'thms_containing' has been discontinued in favour of
  5723 'find_theorems'; INCOMPATIBILITY.
  5724 
  5725 * Communication with Proof General is now 8bit clean, which means that
  5726 Unicode text in UTF-8 encoding may be used within theory texts (both
  5727 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5728 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5729 
  5730   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5731   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5732 
  5733 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5734 Classical Reasoner.  Typical big applications run around 2 times
  5735 faster.
  5736 
  5737 
  5738 *** Document preparation ***
  5739 
  5740 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5741 of raw sources.  Only those symbols that do not require additional
  5742 LaTeX packages (depending on comments in isabellesym.sty) are
  5743 displayed properly, everything else is left verbatim.  isatool display
  5744 and isatool print are used as front ends (these are subject to the
  5745 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5746 
  5747 * Command tags control specific markup of certain regions of text,
  5748 notably folding and hiding.  Predefined tags include "theory" (for
  5749 theory begin and end), "proof" for proof commands, and "ML" for
  5750 commands involving ML code; the additional tags "visible" and
  5751 "invisible" are unused by default.  Users may give explicit tag
  5752 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5753 interpretation of tags is determined by the LaTeX job during document
  5754 preparation: see option -V of isatool usedir, or options -n and -t of
  5755 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5756 \isadroptag.
  5757 
  5758 Several document versions may be produced at the same time via isatool
  5759 usedir (the generated index.html will link all of them).  Typical
  5760 specifications include ''-V document=theory,proof,ML'' to present
  5761 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5762 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5763 these parts without any formal replacement text.  The Isabelle site
  5764 default settings produce ''document'' and ''outline'' versions as
  5765 specified above.
  5766 
  5767 * Several new antiquotations:
  5768 
  5769   @{term_type term} prints a term with its type annotated;
  5770 
  5771   @{typeof term} prints the type of a term;
  5772 
  5773   @{const const} is the same as @{term const}, but checks that the
  5774   argument is a known logical constant;
  5775 
  5776   @{term_style style term} and @{thm_style style thm} print a term or
  5777   theorem applying a "style" to it
  5778 
  5779   @{ML text}
  5780 
  5781 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5782 definitions, equations, inequations etc., 'concl' printing only the
  5783 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5784 to print the specified premise.  TermStyle.add_style provides an ML
  5785 interface for introducing further styles.  See also the "LaTeX Sugar"
  5786 document practical applications.  The ML antiquotation prints
  5787 type-checked ML expressions verbatim.
  5788 
  5789 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5790 and 'text' support optional locale specification '(in loc)', which
  5791 specifies the default context for interpreting antiquotations.  For
  5792 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5793 
  5794 * Option 'locale=NAME' of antiquotations specifies an alternative
  5795 context interpreting the subsequent argument.  For example: @{thm
  5796 [locale=lattice] inf_assoc}.
  5797 
  5798 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5799 a proof context.
  5800 
  5801 * Proper output of antiquotations for theory commands involving a
  5802 proof context (such as 'locale' or 'theorem (in loc) ...').
  5803 
  5804 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5805 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5806 
  5807 * isatool usedir: new option -C (default true) controls whether option
  5808 -D should include a copy of the original document directory; -C false
  5809 prevents unwanted effects such as copying of administrative CVS data.
  5810 
  5811 
  5812 *** Pure ***
  5813 
  5814 * Considerably improved version of 'constdefs' command.  Now performs
  5815 automatic type-inference of declared constants; additional support for
  5816 local structure declarations (cf. locales and HOL records), see also
  5817 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5818 sequential dependencies of definitions within a single 'constdefs'
  5819 section; moreover, the declared name needs to be an identifier.  If
  5820 all fails, consider to fall back on 'consts' and 'defs' separately.
  5821 
  5822 * Improved indexed syntax and implicit structures.  First of all,
  5823 indexed syntax provides a notational device for subscripted
  5824 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5825 expressions.  Secondly, in a local context with structure
  5826 declarations, number indexes \<^sub>n or the empty index (default
  5827 number 1) refer to a certain fixed variable implicitly; option
  5828 show_structs controls printing of implicit structures.  Typical
  5829 applications of these concepts involve record types and locales.
  5830 
  5831 * New command 'no_syntax' removes grammar declarations (and
  5832 translations) resulting from the given syntax specification, which is
  5833 interpreted in the same manner as for the 'syntax' command.
  5834 
  5835 * 'Advanced' translation functions (parse_translation etc.) may depend
  5836 on the signature of the theory context being presently used for
  5837 parsing/printing, see also isar-ref manual.
  5838 
  5839 * Improved 'oracle' command provides a type-safe interface to turn an
  5840 ML expression of type theory -> T -> term into a primitive rule of
  5841 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5842 is already included here); see also FOL/ex/IffExample.thy;
  5843 INCOMPATIBILITY.
  5844 
  5845 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5846 before); "cI" is no longer bound, use "c.intro" instead.
  5847 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5848 axclasses vs. locales.
  5849 
  5850 * Improved internal renaming of symbolic identifiers -- attach primes
  5851 instead of base 26 numbers.
  5852 
  5853 * New flag show_question_marks controls printing of leading question
  5854 marks in schematic variable names.
  5855 
  5856 * In schematic variable names, *any* symbol following \<^isub> or
  5857 \<^isup> is now treated as part of the base name.  For example, the
  5858 following works without printing of awkward ".0" indexes:
  5859 
  5860   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5861     by simp
  5862 
  5863 * Inner syntax includes (*(*nested*) comments*).
  5864 
  5865 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5866 annotations as "(00...)".
  5867 
  5868 * Clear separation of logical types and nonterminals, where the latter
  5869 may only occur in 'syntax' specifications or type abbreviations.
  5870 Before that distinction was only partially implemented via type class
  5871 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5872 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5873 exotic syntax specifications may require further adaption
  5874 (e.g. Cube/Cube.thy).
  5875 
  5876 * Removed obsolete type class "logic", use the top sort {} instead.
  5877 Note that non-logical types should be declared as 'nonterminals'
  5878 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5879 specifications.
  5880 
  5881 * Attributes 'induct' and 'cases': type or set names may now be
  5882 locally fixed variables as well.
  5883 
  5884 * Simplifier: can now control the depth to which conditional rewriting
  5885 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5886 Limit.
  5887 
  5888 * Simplifier: simplification procedures may now take the current
  5889 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5890 interface), which is very useful for calling the Simplifier
  5891 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5892 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5893 low-level mk_simproc no longer applies Logic.varify internally, to
  5894 allow for use in a context of fixed variables.
  5895 
  5896 * thin_tac now works even if the assumption being deleted contains !!
  5897 or ==>.  More generally, erule now works even if the major premise of
  5898 the elimination rule contains !! or ==>.
  5899 
  5900 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5901 
  5902 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5903 from Pure, which contains all common declarations already.  Both
  5904 theories are defined via plain Isabelle/Isar .thy files.
  5905 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5906 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5907 use isatool fixcpure to adapt your theory and ML sources.
  5908 
  5909 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5910 selections of theorems in named facts via index ranges.
  5911 
  5912 * 'print_theorems': in theory mode, really print the difference
  5913 wrt. the last state (works for interactive theory development only),
  5914 in proof mode print all local facts (cf. 'print_facts');
  5915 
  5916 * 'hide': option '(open)' hides only base names.
  5917 
  5918 * More efficient treatment of intermediate checkpoints in interactive
  5919 theory development.
  5920 
  5921 * Code generator is now invoked via code_module (incremental code
  5922 generation) and code_library (modular code generation, ML structures
  5923 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5924 must be quoted when used as identifiers.
  5925 
  5926 * New 'value' command for reading, evaluating and printing terms using
  5927 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5928 quoted when used as identifier.
  5929 
  5930 
  5931 *** Locales ***
  5932 
  5933 * New commands for the interpretation of locale expressions in
  5934 theories (1), locales (2) and proof contexts (3).  These generate
  5935 proof obligations from the expression specification.  After the
  5936 obligations have been discharged, theorems of the expression are added
  5937 to the theory, target locale or proof context.  The synopsis of the
  5938 commands is a follows:
  5939 
  5940   (1) interpretation expr inst
  5941   (2) interpretation target < expr
  5942   (3) interpret expr inst
  5943 
  5944 Interpretation in theories and proof contexts require a parameter
  5945 instantiation of terms from the current context.  This is applied to
  5946 specifications and theorems of the interpreted expression.
  5947 Interpretation in locales only permits parameter renaming through the
  5948 locale expression.  Interpretation is smart in that interpretations
  5949 that are active already do not occur in proof obligations, neither are
  5950 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5951 inspect active interpretations of a particular locale.  For details,
  5952 see the Isar Reference manual.  Examples can be found in
  5953 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5954 
  5955 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5956 'interpret' instead.
  5957 
  5958 * New context element 'constrains' for adding type constraints to
  5959 parameters.
  5960 
  5961 * Context expressions: renaming of parameters with syntax
  5962 redeclaration.
  5963 
  5964 * Locale declaration: 'includes' disallowed.
  5965 
  5966 * Proper static binding of attribute syntax -- i.e. types / terms /
  5967 facts mentioned as arguments are always those of the locale definition
  5968 context, independently of the context of later invocations.  Moreover,
  5969 locale operations (renaming and type / term instantiation) are applied
  5970 to attribute arguments as expected.
  5971 
  5972 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5973 actual attributes; rare situations may require Attrib.attribute to
  5974 embed those attributes into Attrib.src that lack concrete syntax.
  5975 Attribute implementations need to cooperate properly with the static
  5976 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5977 Attrib.XXX_thm etc. already do the right thing without further
  5978 intervention.  Only unusual applications -- such as "where" or "of"
  5979 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5980 on the context and the facts involved -- may have to assign parsed
  5981 values to argument tokens explicitly.
  5982 
  5983 * Changed parameter management in theorem generation for long goal
  5984 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5985 theorem statement in rare situations.
  5986 
  5987 * Locale inspection command 'print_locale' omits notes elements.  Use
  5988 'print_locale!' to have them included in the output.
  5989 
  5990 
  5991 *** Provers ***
  5992 
  5993 * Provers/hypsubst.ML: improved version of the subst method, for
  5994 single-step rewriting: it now works in bound variable contexts. New is
  5995 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5996 rewrite a different subterm than the original subst method, which is
  5997 still available as 'simplesubst'.
  5998 
  5999 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  6000 and quasi orders.
  6001 
  6002 * Provers/trancl.ML: new transitivity reasoner for transitive and
  6003 reflexive-transitive closure of relations.
  6004 
  6005 * Provers/blast.ML: new reference depth_limit to make blast's depth
  6006 limit (previously hard-coded with a value of 20) user-definable.
  6007 
  6008 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  6009 is peformed already.  Object-logics merely need to finish their
  6010 initial simpset configuration as before.  INCOMPATIBILITY.
  6011 
  6012 
  6013 *** HOL ***
  6014 
  6015 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  6016 
  6017   syntax (epsilon)
  6018     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  6019 
  6020 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  6021 and x-symbol; use option '-m epsilon' to get it actually printed.
  6022 Moreover, the mathematically important symbolic identifier \<epsilon>
  6023 becomes available as variable, constant etc.  INCOMPATIBILITY,
  6024 
  6025 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  6026 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  6027 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  6028 support corresponding Isar calculations.
  6029 
  6030 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  6031 instead of ":".
  6032 
  6033 * theory SetInterval: changed the syntax for open intervals:
  6034 
  6035   Old       New
  6036   {..n(}    {..<n}
  6037   {)n..}    {n<..}
  6038   {m..n(}   {m..<n}
  6039   {)m..n}   {m<..n}
  6040   {)m..n(}  {m<..<n}
  6041 
  6042 The old syntax is still supported but will disappear in the next
  6043 release.  For conversion use the following Emacs search and replace
  6044 patterns (these are not perfect but work quite well):
  6045 
  6046   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  6047   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  6048 
  6049 * Theory Commutative_Ring (in Library): method comm_ring for proving
  6050 equalities in commutative rings; method 'algebra' provides a generic
  6051 interface.
  6052 
  6053 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  6054 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  6055 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  6056 be a tuple pattern.
  6057 
  6058 Some new syntax forms are available:
  6059 
  6060   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  6061   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  6062   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  6063   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  6064 
  6065 The latter form "\<Sum>x < k. e" used to be based on a separate
  6066 function "Summation", which has been discontinued.
  6067 
  6068 * theory Finite_Set: in structured induction proofs, the insert case
  6069 is now 'case (insert x F)' instead of the old counterintuitive 'case
  6070 (insert F x)'.
  6071 
  6072 * The 'refute' command has been extended to support a much larger
  6073 fragment of HOL, including axiomatic type classes, constdefs and
  6074 typedefs, inductive datatypes and recursion.
  6075 
  6076 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  6077 Requires zChaff with proof generation to be installed.  See
  6078 HOL/ex/SAT_Examples.thy for examples.
  6079 
  6080 * Datatype induction via method 'induct' now preserves the name of the
  6081 induction variable. For example, when proving P(xs::'a list) by
  6082 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  6083 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  6084 in unstructured proof scripts.
  6085 
  6086 * Reworked implementation of records.  Improved scalability for
  6087 records with many fields, avoiding performance problems for type
  6088 inference. Records are no longer composed of nested field types, but
  6089 of nested extension types. Therefore the record type only grows linear
  6090 in the number of extensions and not in the number of fields.  The
  6091 top-level (users) view on records is preserved.  Potential
  6092 INCOMPATIBILITY only in strange cases, where the theory depends on the
  6093 old record representation. The type generated for a record is called
  6094 <record_name>_ext_type.
  6095 
  6096 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  6097 proofs triggered by a record definition or a simproc (if
  6098 quick_and_dirty is enabled).  Definitions of large records can take
  6099 quite long.
  6100 
  6101 New simproc record_upd_simproc for simplification of multiple record
  6102 updates enabled by default.  Moreover, trivial updates are also
  6103 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  6104 occasionally, since simplification is more powerful by default.
  6105 
  6106 * typedef: proper support for polymorphic sets, which contain extra
  6107 type-variables in the term.
  6108 
  6109 * Simplifier: automatically reasons about transitivity chains
  6110 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  6111 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  6112 old proofs break occasionally as simplification may now solve more
  6113 goals than previously.
  6114 
  6115 * Simplifier: converts x <= y into x = y if assumption y <= x is
  6116 present.  Works for all partial orders (class "order"), in particular
  6117 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  6118 just like y <= x.
  6119 
  6120 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  6121 bound variable or a constant then the let is unfolded.  Otherwise
  6122 first a is simplified to b, and then f b is simplified to g. If
  6123 possible we abstract b from g arriving at "let x = b in h x",
  6124 otherwise we unfold the let and arrive at g.  The simproc can be
  6125 enabled/disabled by the reference use_let_simproc.  Potential
  6126 INCOMPATIBILITY since simplification is more powerful by default.
  6127 
  6128 * Classical reasoning: the meson method now accepts theorems as arguments.
  6129 
  6130 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  6131 jobs to provide advice on the provability of subgoals.
  6132 
  6133 * Theory OrderedGroup and Ring_and_Field: various additions and
  6134 improvements to faciliate calculations involving equalities and
  6135 inequalities.
  6136 
  6137 The following theorems have been eliminated or modified
  6138 (INCOMPATIBILITY):
  6139 
  6140   abs_eq             now named abs_of_nonneg
  6141   abs_of_ge_0        now named abs_of_nonneg
  6142   abs_minus_eq       now named abs_of_nonpos
  6143   imp_abs_id         now named abs_of_nonneg
  6144   imp_abs_neg_id     now named abs_of_nonpos
  6145   mult_pos           now named mult_pos_pos
  6146   mult_pos_le        now named mult_nonneg_nonneg
  6147   mult_pos_neg_le    now named mult_nonneg_nonpos
  6148   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  6149   mult_neg           now named mult_neg_neg
  6150   mult_neg_le        now named mult_nonpos_nonpos
  6151 
  6152 * The following lemmas in Ring_and_Field have been added to the simplifier:
  6153      
  6154      zero_le_square
  6155      not_square_less_zero 
  6156 
  6157   The following lemmas have been deleted from Real/RealPow:
  6158   
  6159      realpow_zero_zero
  6160      realpow_two
  6161      realpow_less
  6162      zero_le_power
  6163      realpow_two_le
  6164      abs_realpow_two
  6165      realpow_two_abs     
  6166 
  6167 * Theory Parity: added rules for simplifying exponents.
  6168 
  6169 * Theory List:
  6170 
  6171 The following theorems have been eliminated or modified
  6172 (INCOMPATIBILITY):
  6173 
  6174   list_all_Nil       now named list_all.simps(1)
  6175   list_all_Cons      now named list_all.simps(2)
  6176   list_all_conv      now named list_all_iff
  6177   set_mem_eq         now named mem_iff
  6178 
  6179 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  6180 asymptotic "big O" calculations.  See the notes in BigO.thy.
  6181 
  6182 
  6183 *** HOL-Complex ***
  6184 
  6185 * Theory RealDef: better support for embedding natural numbers and
  6186 integers in the reals.
  6187 
  6188 The following theorems have been eliminated or modified
  6189 (INCOMPATIBILITY):
  6190 
  6191   exp_ge_add_one_self  now requires no hypotheses
  6192   real_of_int_add      reversed direction of equality (use [symmetric])
  6193   real_of_int_minus    reversed direction of equality (use [symmetric])
  6194   real_of_int_diff     reversed direction of equality (use [symmetric])
  6195   real_of_int_mult     reversed direction of equality (use [symmetric])
  6196 
  6197 * Theory RComplete: expanded support for floor and ceiling functions.
  6198 
  6199 * Theory Ln is new, with properties of the natural logarithm
  6200 
  6201 * Hyperreal: There is a new type constructor "star" for making
  6202 nonstandard types.  The old type names are now type synonyms:
  6203 
  6204   hypreal = real star
  6205   hypnat = nat star
  6206   hcomplex = complex star
  6207 
  6208 * Hyperreal: Many groups of similarly-defined constants have been
  6209 replaced by polymorphic versions (INCOMPATIBILITY):
  6210 
  6211   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  6212 
  6213   starset      <-- starsetNat, starsetC
  6214   *s*          <-- *sNat*, *sc*
  6215   starset_n    <-- starsetNat_n, starsetC_n
  6216   *sn*         <-- *sNatn*, *scn*
  6217   InternalSets <-- InternalNatSets, InternalCSets
  6218 
  6219   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  6220   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  6221   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  6222   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  6223   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  6224 
  6225 * Hyperreal: Many type-specific theorems have been removed in favor of
  6226 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  6227 
  6228   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  6229   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  6230   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  6231   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  6232   right_minus <-- hypreal_add_minus
  6233   left_minus <-- {hypreal,hcomplex}_add_minus_left
  6234   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  6235   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  6236   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  6237   mult_1_right <-- hcomplex_mult_one_right
  6238   mult_zero_left <-- hcomplex_mult_zero_left
  6239   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  6240   right_distrib <-- hypnat_add_mult_distrib2
  6241   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  6242   right_inverse <-- hypreal_mult_inverse
  6243   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  6244   order_refl <-- {hypreal,hypnat}_le_refl
  6245   order_trans <-- {hypreal,hypnat}_le_trans
  6246   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  6247   order_less_le <-- {hypreal,hypnat}_less_le
  6248   linorder_linear <-- {hypreal,hypnat}_le_linear
  6249   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  6250   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  6251   add_nonneg_nonneg <-- hypreal_le_add_order
  6252 
  6253 * Hyperreal: Separate theorems having to do with type-specific
  6254 versions of constants have been merged into theorems that apply to the
  6255 new polymorphic constants (INCOMPATIBILITY):
  6256 
  6257   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  6258   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  6259   STAR_Un <-- {STAR,NatStar,STARC}_Un
  6260   STAR_Int <-- {STAR,NatStar,STARC}_Int
  6261   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  6262   STAR_subset <-- {STAR,NatStar,STARC}_subset
  6263   STAR_mem <-- {STAR,NatStar,STARC}_mem
  6264   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  6265   STAR_diff <-- {STAR,STARC}_diff
  6266   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  6267     STARC_hcomplex_of_complex}_image_subset
  6268   starset_n_Un <-- starset{Nat,C}_n_Un
  6269   starset_n_Int <-- starset{Nat,C}_n_Int
  6270   starset_n_Compl <-- starset{Nat,C}_n_Compl
  6271   starset_n_diff <-- starset{Nat,C}_n_diff
  6272   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  6273   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  6274   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  6275   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  6276   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  6277   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  6278   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  6279   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  6280   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  6281   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  6282   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  6283   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  6284   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  6285   starfun_diff <-- starfun{C,RC,CR}_diff
  6286   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  6287   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  6288   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  6289   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  6290   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  6291   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  6292   starfun_Id <-- starfunC_Id
  6293   starfun_approx <-- starfun{Nat,CR}_approx
  6294   starfun_capprox <-- starfun{C,RC}_capprox
  6295   starfun_abs <-- starfunNat_rabs
  6296   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  6297   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  6298   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  6299   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  6300   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  6301   starfun_add_approx <-- starfunCR_add_approx
  6302   starfun_inverse_inverse <-- starfunC_inverse_inverse
  6303   starfun_divide <-- starfun{C,CR,RC}_divide
  6304   starfun_n <-- starfun{Nat,C}_n
  6305   starfun_n_mult <-- starfun{Nat,C}_n_mult
  6306   starfun_n_add <-- starfun{Nat,C}_n_add
  6307   starfun_n_add_minus <-- starfunNat_n_add_minus
  6308   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  6309   starfun_n_minus <-- starfun{Nat,C}_n_minus
  6310   starfun_n_eq <-- starfun{Nat,C}_n_eq
  6311 
  6312   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  6313   star_n_minus <-- {hypreal,hcomplex}_minus
  6314   star_n_diff <-- {hypreal,hcomplex}_diff
  6315   star_n_mult <-- {hypreal,hcomplex}_mult
  6316   star_n_inverse <-- {hypreal,hcomplex}_inverse
  6317   star_n_le <-- {hypreal,hypnat}_le
  6318   star_n_less <-- {hypreal,hypnat}_less
  6319   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  6320   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  6321   star_n_abs <-- hypreal_hrabs
  6322   star_n_divide <-- hcomplex_divide
  6323 
  6324   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  6325   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  6326   star_of_diff <-- hypreal_of_real_diff
  6327   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  6328   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  6329   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  6330   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  6331   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  6332   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  6333   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  6334   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  6335   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  6336   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  6337   star_of_number_of <-- {hypreal,hcomplex}_number_of
  6338   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  6339   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  6340   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  6341   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  6342   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  6343   star_of_power <-- hypreal_of_real_power
  6344   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  6345 
  6346 * Hyperreal: new method "transfer" that implements the transfer
  6347 principle of nonstandard analysis. With a subgoal that mentions
  6348 nonstandard types like "'a star", the command "apply transfer"
  6349 replaces it with an equivalent one that mentions only standard types.
  6350 To be successful, all free variables must have standard types; non-
  6351 standard variables must have explicit universal quantifiers.
  6352 
  6353 * Hyperreal: A theory of Taylor series.
  6354 
  6355 
  6356 *** HOLCF ***
  6357 
  6358 * Discontinued special version of 'constdefs' (which used to support
  6359 continuous functions) in favor of the general Pure one with full
  6360 type-inference.
  6361 
  6362 * New simplification procedure for solving continuity conditions; it
  6363 is much faster on terms with many nested lambda abstractions (cubic
  6364 instead of exponential time).
  6365 
  6366 * New syntax for domain package: selector names are now optional.
  6367 Parentheses should be omitted unless argument is lazy, for example:
  6368 
  6369   domain 'a stream = cons "'a" (lazy "'a stream")
  6370 
  6371 * New command 'fixrec' for defining recursive functions with pattern
  6372 matching; defining multiple functions with mutual recursion is also
  6373 supported.  Patterns may include the constants cpair, spair, up, sinl,
  6374 sinr, or any data constructor defined by the domain package. The given
  6375 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  6376 syntax and examples.
  6377 
  6378 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  6379 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  6380 but the proof obligation additionally includes an admissibility
  6381 requirement. The packages generate instances of class cpo or pcpo,
  6382 with continuity and strictness theorems for Rep and Abs.
  6383 
  6384 * HOLCF: Many theorems have been renamed according to a more standard naming
  6385 scheme (INCOMPATIBILITY):
  6386 
  6387   foo_inject:  "foo$x = foo$y ==> x = y"
  6388   foo_eq:      "(foo$x = foo$y) = (x = y)"
  6389   foo_less:    "(foo$x << foo$y) = (x << y)"
  6390   foo_strict:  "foo$UU = UU"
  6391   foo_defined: "... ==> foo$x ~= UU"
  6392   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  6393 
  6394 
  6395 *** ZF ***
  6396 
  6397 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  6398 including the First Isomorphism Theorem (on quotienting by the kernel
  6399 of a homomorphism).
  6400 
  6401 * ZF/Simplifier: install second copy of type solver that actually
  6402 makes use of TC rules declared to Isar proof contexts (or locales);
  6403 the old version is still required for ML proof scripts.
  6404 
  6405 
  6406 *** Cube ***
  6407 
  6408 * Converted to Isar theory format; use locales instead of axiomatic
  6409 theories.
  6410 
  6411 
  6412 *** ML ***
  6413 
  6414 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6415 for ||>, ||>>, |>>,
  6416 
  6417 * Pure/library.ML no longer defines its own option datatype, but uses
  6418 that of the SML basis, which has constructors NONE and SOME instead of
  6419 None and Some, as well as exception Option.Option instead of OPTION.
  6420 The functions the, if_none, is_some, is_none have been adapted
  6421 accordingly, while Option.map replaces apsome.
  6422 
  6423 * Pure/library.ML: the exception LIST has been given up in favour of
  6424 the standard exceptions Empty and Subscript, as well as
  6425 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6426 superceded by the standard hd and tl functions etc.
  6427 
  6428 A number of basic list functions are no longer exported to the ML
  6429 toplevel, as they are variants of predefined functions.  The following
  6430 suggests how one can translate existing code:
  6431 
  6432     rev_append xs ys = List.revAppend (xs, ys)
  6433     nth_elem (i, xs) = List.nth (xs, i)
  6434     last_elem xs = List.last xs
  6435     flat xss = List.concat xss
  6436     seq fs = List.app fs
  6437     partition P xs = List.partition P xs
  6438     mapfilter f xs = List.mapPartial f xs
  6439 
  6440 * Pure/library.ML: several combinators for linear functional
  6441 transformations, notably reverse application and composition:
  6442 
  6443   x |> f                f #> g
  6444   (x, y) |-> f          f #-> g
  6445 
  6446 * Pure/library.ML: introduced/changed precedence of infix operators:
  6447 
  6448   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6449   infix 2 ?;
  6450   infix 3 o oo ooo oooo;
  6451   infix 4 ~~ upto downto;
  6452 
  6453 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6454 infix operators.
  6455 
  6456 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6457 fold_map support linear functional transformations and nesting.  For
  6458 example:
  6459 
  6460   fold f [x1, ..., xN] y =
  6461     y |> f x1 |> ... |> f xN
  6462 
  6463   (fold o fold) f [xs1, ..., xsN] y =
  6464     y |> fold f xs1 |> ... |> fold f xsN
  6465 
  6466   fold f [x1, ..., xN] =
  6467     f x1 #> ... #> f xN
  6468 
  6469   (fold o fold) f [xs1, ..., xsN] =
  6470     fold f xs1 #> ... #> fold f xsN
  6471 
  6472 * Pure/library.ML: the following selectors on type 'a option are
  6473 available:
  6474 
  6475   the:               'a option -> 'a  (*partial*)
  6476   these:             'a option -> 'a  where 'a = 'b list
  6477   the_default: 'a -> 'a option -> 'a
  6478   the_list:          'a option -> 'a list
  6479 
  6480 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6481 basic operations for association lists, following natural argument
  6482 order; moreover the explicit equality predicate passed here avoids
  6483 potentially expensive polymorphic runtime equality checks.
  6484 The old functions may be expressed as follows:
  6485 
  6486   assoc = uncurry (AList.lookup (op =))
  6487   assocs = these oo AList.lookup (op =)
  6488   overwrite = uncurry (AList.update (op =)) o swap
  6489 
  6490 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6491 
  6492   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6493   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6494 
  6495 replacing make_keylist and keyfilter (occassionally used)
  6496 Naive rewrites:
  6497 
  6498   make_keylist = AList.make
  6499   keyfilter = AList.find (op =)
  6500 
  6501 * eq_fst and eq_snd now take explicit equality parameter, thus
  6502   avoiding eqtypes. Naive rewrites:
  6503 
  6504     eq_fst = eq_fst (op =)
  6505     eq_snd = eq_snd (op =)
  6506 
  6507 * Removed deprecated apl and apr (rarely used).
  6508   Naive rewrites:
  6509 
  6510     apl (n, op) =>>= curry op n
  6511     apr (op, m) =>>= fn n => op (n, m)
  6512 
  6513 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6514 provides a reasonably efficient light-weight implementation of sets as
  6515 lists.
  6516 
  6517 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6518 few new operations; existing lookup and update are now curried to
  6519 follow natural argument order (for use with fold etc.);
  6520 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6521 
  6522 * Pure/General: output via the Isabelle channels of
  6523 writeln/warning/error etc. is now passed through Output.output, with a
  6524 hook for arbitrary transformations depending on the print_mode
  6525 (cf. Output.add_mode -- the first active mode that provides a output
  6526 function wins).  Already formatted output may be embedded into further
  6527 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6528 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6529 accommodate easy composition of diagnostic messages etc.  Programmers
  6530 rarely need to care about Output.output or Output.raw at all, with
  6531 some notable exceptions: Output.output is required when bypassing the
  6532 standard channels (writeln etc.), or in token translations to produce
  6533 properly formatted results; Output.raw is required when capturing
  6534 already output material that will eventually be presented to the user
  6535 a second time.  For the default print mode, both Output.output and
  6536 Output.raw have no effect.
  6537 
  6538 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6539 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6540 cumulative results are displayed at the end of a batch session.
  6541 
  6542 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6543 replaced by File.platform_path and File.shell_path (with appropriate
  6544 hooks).  This provides a clean interface for unusual systems where the
  6545 internal and external process view of file names are different.
  6546 
  6547 * Pure: more efficient orders for basic syntactic entities: added
  6548 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6549 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6550 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6551 orders now -- potential INCOMPATIBILITY for code that depends on a
  6552 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6553 Library.sort_strings on result).
  6554 
  6555 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6556 fold_types traverse types/terms from left to right, observing natural
  6557 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6558 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6559 
  6560 * Pure: name spaces have been refined, with significant changes of the
  6561 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6562 to extern(_table).  The plain name entry path is superceded by a
  6563 general 'naming' context, which also includes the 'policy' to produce
  6564 a fully qualified name and external accesses of a fully qualified
  6565 name; NameSpace.extend is superceded by context dependent
  6566 Sign.declare_name.  Several theory and proof context operations modify
  6567 the naming context.  Especially note Theory.restore_naming and
  6568 ProofContext.restore_naming to get back to a sane state; note that
  6569 Theory.add_path is no longer sufficient to recover from
  6570 Theory.absolute_path in particular.
  6571 
  6572 * Pure: new flags short_names (default false) and unique_names
  6573 (default true) for controlling output of qualified names.  If
  6574 short_names is set, names are printed unqualified.  If unique_names is
  6575 reset, the name prefix is reduced to the minimum required to achieve
  6576 the original result when interning again, even if there is an overlap
  6577 with earlier declarations.
  6578 
  6579 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6580 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6581 (useful for printing error messages).  INCOMPATIBILITY.
  6582 
  6583 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6584 Theory.theory are now identified, referring to the universal
  6585 Context.theory (see Pure/context.ML).  Actual signature and theory
  6586 content is managed as theory data.  The old code and interfaces were
  6587 spread over many files and structures; the new arrangement introduces
  6588 considerable INCOMPATIBILITY to gain more clarity:
  6589 
  6590   Context -- theory management operations (name, identity, inclusion,
  6591     parents, ancestors, merge, etc.), plus generic theory data;
  6592 
  6593   Sign -- logical signature and syntax operations (declaring consts,
  6594     types, etc.), plus certify/read for common entities;
  6595 
  6596   Theory -- logical theory operations (stating axioms, definitions,
  6597     oracles), plus a copy of logical signature operations (consts,
  6598     types, etc.); also a few basic management operations (Theory.copy,
  6599     Theory.merge, etc.)
  6600 
  6601 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6602 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6603 for convenience -- they merely return the theory.
  6604 
  6605 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6606 
  6607 * Pure: the Isar proof context type is already defined early in Pure
  6608 as Context.proof (note that ProofContext.context and Proof.context are
  6609 aliases, where the latter is the preferred name).  This enables other
  6610 Isabelle components to refer to that type even before Isar is present.
  6611 
  6612 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6613 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6614 any of these kinds.  For example, Sign.intern typeK is now
  6615 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6616 Theory.hide_types.  Also note that former
  6617 Theory.hide_classes/types/consts are now
  6618 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6619 internalize their arguments!  INCOMPATIBILITY.
  6620 
  6621 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6622 datatype thmref (with constructors Name and NameSelection) instead of
  6623 plain string -- INCOMPATIBILITY;
  6624 
  6625 * Pure: cases produced by proof methods specify options, where NONE
  6626 means to remove case bindings -- INCOMPATIBILITY in
  6627 (RAW_)METHOD_CASES.
  6628 
  6629 * Pure: the following operations retrieve axioms or theorems from a
  6630 theory node or theory hierarchy, respectively:
  6631 
  6632   Theory.axioms_of: theory -> (string * term) list
  6633   Theory.all_axioms_of: theory -> (string * term) list
  6634   PureThy.thms_of: theory -> (string * thm) list
  6635   PureThy.all_thms_of: theory -> (string * thm) list
  6636 
  6637 * Pure: print_tac now outputs the goal through the trace channel.
  6638 
  6639 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6640 Reference Toplevel.debug (default false) controls detailed printing
  6641 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6642 controls execution profiling -- set to 1 for time and 2 for space
  6643 (both increase the runtime).
  6644 
  6645 * Isar session: The initial use of ROOT.ML is now always timed,
  6646 i.e. the log will show the actual process times, in contrast to the
  6647 elapsed wall-clock time that the outer shell wrapper produces.
  6648 
  6649 * Simplifier: improved handling of bound variables (nameless
  6650 representation, avoid allocating new strings).  Simprocs that invoke
  6651 the Simplifier recursively should use Simplifier.inherit_bounds to
  6652 avoid local name clashes.  Failure to do so produces warnings
  6653 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6654 for further details.
  6655 
  6656 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6657 bindings for all theorems stored within a given theory; this may help
  6658 in porting non-Isar theories to Isar ones, while keeping ML proof
  6659 scripts for the time being.
  6660 
  6661 * ML operator HTML.with_charset specifies the charset begin used for
  6662 generated HTML files.  For example:
  6663 
  6664   HTML.with_charset "utf-8" use_thy "Hebrew";
  6665   HTML.with_charset "utf-8" use_thy "Chinese";
  6666 
  6667 
  6668 *** System ***
  6669 
  6670 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6671 isabelle, isatool etc.).
  6672 
  6673 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6674 isatool doc, isatool mkdir, display_drafts etc.).
  6675 
  6676 * isatool usedir: option -f allows specification of the ML file to be
  6677 used by Isabelle; default is ROOT.ML.
  6678 
  6679 * New isatool version outputs the version identifier of the Isabelle
  6680 distribution being used.
  6681 
  6682 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6683 (containing Boolean satisfiability problems) into Isabelle/HOL
  6684 theories.
  6685 
  6686 
  6687 
  6688 New in Isabelle2004 (April 2004)
  6689 --------------------------------
  6690 
  6691 *** General ***
  6692 
  6693 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6694   Replaces linorder.ML.
  6695 
  6696 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6697   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6698   (\<a>...\<z>), are now considered normal letters, and can therefore
  6699   be used anywhere where an ASCII letter (a...zA...Z) has until
  6700   now. COMPATIBILITY: This obviously changes the parsing of some
  6701   terms, especially where a symbol has been used as a binder, say
  6702   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6703   as an identifier.  Fix it by inserting a space around former
  6704   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6705   existing theory and ML files.
  6706 
  6707 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6708 
  6709 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6710   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6711   a normal (but invisible) letter. For multiple letter subscripts repeat
  6712   \<^isub> like this: x\<^isub>1\<^isub>2.
  6713 
  6714 * Pure: There are now sub-/superscripts that can span more than one
  6715   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6716   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6717   superscript. The new control characters are not identifier parts.
  6718 
  6719 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6720   content of "..." to the latex file instead of \isacntrl... . The "..."
  6721   may consist of any printable characters excluding the end bracket >.
  6722 
  6723 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6724   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6725   declare constants "final", which prevents their being given a definition
  6726   later.  It is useful for constants whose behaviour is fixed axiomatically
  6727   rather than definitionally, such as the meta-logic connectives.
  6728 
  6729 * Pure: 'instance' now handles general arities with general sorts
  6730   (i.e. intersections of classes),
  6731 
  6732 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6733   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6734   It can be changed to alter the colors/layout of generated pages.
  6735 
  6736 
  6737 *** Isar ***
  6738 
  6739 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6740   cut_tac, subgoal_tac and thin_tac:
  6741   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6742     locales are no longer forced to write Isar proof scripts.
  6743     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6744     emulations.
  6745   - INCOMPATIBILITY: names of variables to be instantiated may no
  6746     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6747     This is consistent with the instantiation attribute "where".
  6748 
  6749 * Attributes "where" and "of":
  6750   - Now take type variables of instantiated theorem into account when reading
  6751     the instantiation string.  This fixes a bug that caused instantiated
  6752     theorems to have too special types in some circumstances.
  6753   - "where" permits explicit instantiations of type variables.
  6754 
  6755 * Calculation commands "moreover" and "also" no longer interfere with
  6756   current facts ("this"), admitting arbitrary combinations with "then"
  6757   and derived forms.
  6758 
  6759 * Locales:
  6760   - Goal statements involving the context element "includes" no longer
  6761     generate theorems with internal delta predicates (those ending on
  6762     "_axioms") in the premise.
  6763     Resolve particular premise with <locale>.intro to obtain old form.
  6764   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6765     specification and "includes" elements in goal statement.
  6766   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6767     [intro?] and [elim?] (respectively) by default.
  6768   - Experimental command for instantiation of locales in proof contexts:
  6769         instantiate <label>[<attrs>]: <loc>
  6770     Instantiates locale <loc> and adds all its theorems to the current context
  6771     taking into account their attributes.  Label and attrs are optional
  6772     modifiers, like in theorem declarations.  If present, names of
  6773     instantiated theorems are qualified with <label>, and the attributes
  6774     <attrs> are applied after any attributes these theorems might have already.
  6775       If the locale has assumptions, a chained fact of the form
  6776     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6777     are derived.  The command does not support old-style locales declared
  6778     with "locale (open)".
  6779       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6780 
  6781 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6782   (Isar) contexts.
  6783 
  6784 
  6785 *** HOL ***
  6786 
  6787 * Proof import: new image HOL4 contains the imported library from
  6788   the HOL4 system with about 2500 theorems. It is imported by
  6789   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6790   can be used like any other Isabelle image.  See
  6791   HOL/Import/HOL/README for more information.
  6792 
  6793 * Simplifier:
  6794   - Much improved handling of linear and partial orders.
  6795     Reasoners for linear and partial orders are set up for type classes
  6796     "linorder" and "order" respectively, and are added to the default simpset
  6797     as solvers.  This means that the simplifier can build transitivity chains
  6798     to solve goals from the assumptions.
  6799   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6800     of blast or auto after simplification become unnecessary because the goal
  6801     is solved by simplification already.
  6802 
  6803 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6804     all proved in axiomatic type classes for semirings, rings and fields.
  6805 
  6806 * Numerics:
  6807   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6808     now formalized using the Ring_and_Field theory mentioned above.
  6809   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6810     than before, because now they are set up once in a generic manner.
  6811   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6812     Look for the general versions in Ring_and_Field (and Power if they concern
  6813     exponentiation).
  6814 
  6815 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6816 
  6817 * Records:
  6818   - Record types are now by default printed with their type abbreviation
  6819     instead of the list of all field types. This can be configured via
  6820     the reference "print_record_type_abbr".
  6821   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6822     (not enabled by default).
  6823   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6824     EX x. x = sel r to True (not enabled by default).
  6825   - Tactic "record_split_simp_tac" to split and simplify records added.
  6826 
  6827 * 'specification' command added, allowing for definition by
  6828   specification.  There is also an 'ax_specification' command that
  6829   introduces the new constants axiomatically.
  6830 
  6831 * arith(_tac) is now able to generate counterexamples for reals as well.
  6832 
  6833 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6834 
  6835 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6836   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6837 
  6838 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6839   matrix theory to linear programming.
  6840 
  6841 * Unions and Intersections:
  6842   The latex output syntax of UN and INT has been changed
  6843   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6844   i.e. the index formulae has become a subscript.
  6845   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6846 
  6847 * Unions and Intersections over Intervals:
  6848   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6849   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6850   like in normal math, and corresponding versions for < and for intersection.
  6851 
  6852 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6853   lexicographic dictonary ordering has been added as "lexord".
  6854 
  6855 * ML: the legacy theory structures Int and List have been removed. They had
  6856   conflicted with ML Basis Library structures having the same names.
  6857 
  6858 * 'refute' command added to search for (finite) countermodels.  Only works
  6859   for a fragment of HOL.  The installation of an external SAT solver is
  6860   highly recommended.  See "HOL/Refute.thy" for details.
  6861 
  6862 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6863   formulae under an assignment of free variables to random values.
  6864   In contrast to 'refute', it can deal with inductive datatypes,
  6865   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6866   for examples.
  6867 
  6868 
  6869 *** HOLCF ***
  6870 
  6871 * Streams now come with concatenation and are part of the HOLCF image
  6872 
  6873 
  6874 
  6875 New in Isabelle2003 (May 2003)
  6876 ------------------------------
  6877 
  6878 *** General ***
  6879 
  6880 * Provers/simplifier:
  6881 
  6882   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6883     Assumptions are now subject to complete mutual simplification,
  6884     not just from left to right. The simplifier now preserves
  6885     the order of assumptions.
  6886 
  6887     Potential INCOMPATIBILITY:
  6888 
  6889     -- simp sometimes diverges where the old version did
  6890        not, e.g. invoking simp on the goal
  6891 
  6892         [| P (f x); y = x; f x = f y |] ==> Q
  6893 
  6894        now gives rise to the infinite reduction sequence
  6895 
  6896         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6897 
  6898        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6899        kind of problem.
  6900 
  6901     -- Tactics combining classical reasoner and simplification (such as auto)
  6902        are also affected by this change, because many of them rely on
  6903        simp. They may sometimes diverge as well or yield a different numbers
  6904        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6905        in case of problems. Sometimes subsequent calls to the classical
  6906        reasoner will fail because a preceeding call to the simplifier too
  6907        eagerly simplified the goal, e.g. deleted redundant premises.
  6908 
  6909   - The simplifier trace now shows the names of the applied rewrite rules
  6910 
  6911   - You can limit the number of recursive invocations of the simplifier
  6912     during conditional rewriting (where the simplifie tries to solve the
  6913     conditions before applying the rewrite rule):
  6914     ML "simp_depth_limit := n"
  6915     where n is an integer. Thus you can force termination where previously
  6916     the simplifier would diverge.
  6917 
  6918   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6919 
  6920   - No longer aborts on failed congruence proof.  Instead, the
  6921     congruence is ignored.
  6922 
  6923 * Pure: New generic framework for extracting programs from constructive
  6924   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6925   as HOL/Extraction for some case studies.
  6926 
  6927 * Pure: The main goal of the proof state is no longer shown by default, only
  6928 the subgoals. This behaviour is controlled by a new flag.
  6929    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6930 (ML: Proof.show_main_goal).
  6931 
  6932 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6933 rules whose conclusion matches subgoal 1:
  6934       PG menu: Isabelle/Isar -> Show me -> matching rules
  6935 The rules are ordered by how closely they match the subgoal.
  6936 In particular, rules that solve a subgoal outright are displayed first
  6937 (or rather last, the way they are printed).
  6938 (ML: ProofGeneral.print_intros())
  6939 
  6940 * Pure: New flag trace_unify_fail causes unification to print
  6941 diagnostic information (PG: in trace buffer) when it fails. This is
  6942 useful for figuring out why single step proofs like rule, erule or
  6943 assumption failed.
  6944 
  6945 * Pure: Locale specifications now produce predicate definitions
  6946 according to the body of text (covering assumptions modulo local
  6947 definitions); predicate "loc_axioms" covers newly introduced text,
  6948 while "loc" is cumulative wrt. all included locale expressions; the
  6949 latter view is presented only on export into the global theory
  6950 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6951 on the old view without predicates;
  6952 
  6953 * Pure: predefined locales "var" and "struct" are useful for sharing
  6954 parameters (as in CASL, for example); just specify something like
  6955 ``var x + var y + struct M'' as import;
  6956 
  6957 * Pure: improved thms_containing: proper indexing of facts instead of
  6958 raw theorems; check validity of results wrt. current name space;
  6959 include local facts of proof configuration (also covers active
  6960 locales), cover fixed variables in index; may use "_" in term
  6961 specification; an optional limit for the number of printed facts may
  6962 be given (the default is 40);
  6963 
  6964 * Pure: disallow duplicate fact bindings within new-style theory files
  6965 (batch-mode only);
  6966 
  6967 * Provers: improved induct method: assumptions introduced by case
  6968 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6969 the goal statement); "foo" still refers to all facts collectively;
  6970 
  6971 * Provers: the function blast.overloaded has been removed: all constants
  6972 are regarded as potentially overloaded, which improves robustness in exchange
  6973 for slight decrease in efficiency;
  6974 
  6975 * Provers/linorder: New generic prover for transitivity reasoning over
  6976 linear orders.  Note: this prover is not efficient!
  6977 
  6978 * Isar: preview of problems to finish 'show' now produce an error
  6979 rather than just a warning (in interactive mode);
  6980 
  6981 
  6982 *** HOL ***
  6983 
  6984 * arith(_tac)
  6985 
  6986  - Produces a counter example if it cannot prove a goal.
  6987    Note that the counter example may be spurious if the goal is not a formula
  6988    of quantifier-free linear arithmetic.
  6989    In ProofGeneral the counter example appears in the trace buffer.
  6990 
  6991  - Knows about div k and mod k where k is a numeral of type nat or int.
  6992 
  6993  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6994    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6995    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6996 
  6997 * simp's arithmetic capabilities have been enhanced a bit: it now
  6998 takes ~= in premises into account (by performing a case split);
  6999 
  7000 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  7001 are distributed over a sum of terms;
  7002 
  7003 * New tactic "trans_tac" and method "trans" instantiate
  7004 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  7005 "<=", "<" and "=").
  7006 
  7007 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  7008 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  7009 
  7010 * 'typedef' command has new option "open" to suppress the set
  7011 definition;
  7012 
  7013 * functions Min and Max on finite sets have been introduced (theory
  7014 Finite_Set);
  7015 
  7016 * attribute [symmetric] now works for relations as well; it turns
  7017 (x,y) : R^-1 into (y,x) : R, and vice versa;
  7018 
  7019 * induct over a !!-quantified statement (say !!x1..xn):
  7020   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  7021 
  7022 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  7023 %x. None. Warning: empty_def now refers to the previously hidden definition
  7024 of the empty set.
  7025 
  7026 * Algebra: formalization of classical algebra.  Intended as base for
  7027 any algebraic development in Isabelle.  Currently covers group theory
  7028 (up to Sylow's theorem) and ring theory (Universal Property of
  7029 Univariate Polynomials).  Contributions welcome;
  7030 
  7031 * GroupTheory: deleted, since its material has been moved to Algebra;
  7032 
  7033 * Complex: new directory of the complex numbers with numeric constants,
  7034 nonstandard complex numbers, and some complex analysis, standard and
  7035 nonstandard (Jacques Fleuriot);
  7036 
  7037 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  7038 
  7039 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  7040 Fleuriot);
  7041 
  7042 * Real/HahnBanach: updated and adapted to locales;
  7043 
  7044 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  7045 Gray and Kramer);
  7046 
  7047 * UNITY: added the Meier-Sanders theory of progress sets;
  7048 
  7049 * MicroJava: bytecode verifier and lightweight bytecode verifier
  7050 as abstract algorithms, instantiated to the JVM;
  7051 
  7052 * Bali: Java source language formalization. Type system, operational
  7053 semantics, axiomatic semantics. Supported language features:
  7054 classes, interfaces, objects,virtual methods, static methods,
  7055 static/instance fields, arrays, access modifiers, definite
  7056 assignment, exceptions.
  7057 
  7058 
  7059 *** ZF ***
  7060 
  7061 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  7062 universe, etc.);
  7063 
  7064 * Main ZF: virtually all theories converted to new-style format;
  7065 
  7066 
  7067 *** ML ***
  7068 
  7069 * Pure: Tactic.prove provides sane interface for internal proofs;
  7070 omits the infamous "standard" operation, so this is more appropriate
  7071 than prove_goalw_cterm in many situations (e.g. in simprocs);
  7072 
  7073 * Pure: improved error reporting of simprocs;
  7074 
  7075 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  7076 up simprocs;
  7077 
  7078 
  7079 *** Document preparation ***
  7080 
  7081 * uses \par instead of \\ for line breaks in theory text. This may
  7082 shift some page breaks in large documents. To get the old behaviour
  7083 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  7084 
  7085 * minimized dependencies of isabelle.sty and isabellesym.sty on
  7086 other packages
  7087 
  7088 * \<euro> now needs package babel/greek instead of marvosym (which
  7089 broke \Rightarrow)
  7090 
  7091 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  7092 textcomp package)
  7093 
  7094 
  7095 
  7096 New in Isabelle2002 (March 2002)
  7097 --------------------------------
  7098 
  7099 *** Document preparation ***
  7100 
  7101 * greatly simplified document preparation setup, including more
  7102 graceful interpretation of isatool usedir -i/-d/-D options, and more
  7103 instructive isatool mkdir; users should basically be able to get
  7104 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  7105 users may run a separate document processing stage manually like this:
  7106 "isatool usedir -D output HOL Test && isatool document Test/output";
  7107 
  7108 * theory dependency graph may now be incorporated into documents;
  7109 isatool usedir -g true will produce session_graph.eps/.pdf for use
  7110 with \includegraphics of LaTeX;
  7111 
  7112 * proper spacing of consecutive markup elements, especially text
  7113 blocks after section headings;
  7114 
  7115 * support bold style (for single symbols only), input syntax is like
  7116 this: "\<^bold>\<alpha>" or "\<^bold>A";
  7117 
  7118 * \<bullet> is now output as bold \cdot by default, which looks much
  7119 better in printed text;
  7120 
  7121 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  7122 note that these symbols are currently unavailable in Proof General /
  7123 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  7124 
  7125 * isatool latex no longer depends on changed TEXINPUTS, instead
  7126 isatool document copies the Isabelle style files to the target
  7127 location;
  7128 
  7129 
  7130 *** Isar ***
  7131 
  7132 * Pure/Provers: improved proof by cases and induction;
  7133   - 'case' command admits impromptu naming of parameters (such as
  7134     "case (Suc n)");
  7135   - 'induct' method divinates rule instantiation from the inductive
  7136     claim; no longer requires excessive ?P bindings for proper
  7137     instantiation of cases;
  7138   - 'induct' method properly enumerates all possibilities of set/type
  7139     rules; as a consequence facts may be also passed through *type*
  7140     rules without further ado;
  7141   - 'induct' method now derives symbolic cases from the *rulified*
  7142     rule (before it used to rulify cases stemming from the internal
  7143     atomized version); this means that the context of a non-atomic
  7144     statement becomes is included in the hypothesis, avoiding the
  7145     slightly cumbersome show "PROP ?case" form;
  7146   - 'induct' may now use elim-style induction rules without chaining
  7147     facts, using ``missing'' premises from the goal state; this allows
  7148     rules stemming from inductive sets to be applied in unstructured
  7149     scripts, while still benefitting from proper handling of non-atomic
  7150     statements; NB: major inductive premises need to be put first, all
  7151     the rest of the goal is passed through the induction;
  7152   - 'induct' proper support for mutual induction involving non-atomic
  7153     rule statements (uses the new concept of simultaneous goals, see
  7154     below);
  7155   - append all possible rule selections, but only use the first
  7156     success (no backtracking);
  7157   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  7158   - undeclared rule case names default to numbers 1, 2, 3, ...;
  7159   - added 'print_induct_rules' (covered by help item in recent Proof
  7160     General versions);
  7161   - moved induct/cases attributes to Pure, methods to Provers;
  7162   - generic method setup instantiated for FOL and HOL;
  7163 
  7164 * Pure: support multiple simultaneous goal statements, for example
  7165 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  7166 meta-level mechanism, this acts as if several individual goals had
  7167 been stated separately; in particular common proof methods need to be
  7168 repeated in order to cover all claims; note that a single elimination
  7169 step is *not* sufficient to establish the two conjunctions, so this
  7170 fails:
  7171 
  7172   assume "A & B" then have A and B ..   (*".." fails*)
  7173 
  7174 better use "obtain" in situations as above; alternative refer to
  7175 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  7176 
  7177 * Pure: proper integration with ``locales''; unlike the original
  7178 version by Florian Kammller, Isar locales package high-level proof
  7179 contexts rather than raw logical ones (e.g. we admit to include
  7180 attributes everywhere); operations on locales include merge and
  7181 rename; support for implicit arguments (``structures''); simultaneous
  7182 type-inference over imports and text; see also HOL/ex/Locales.thy for
  7183 some examples;
  7184 
  7185 * Pure: the following commands have been ``localized'', supporting a
  7186 target locale specification "(in name)": 'lemma', 'theorem',
  7187 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  7188 stored both within the locale and at the theory level (exported and
  7189 qualified by the locale name);
  7190 
  7191 * Pure: theory goals may now be specified in ``long'' form, with
  7192 ad-hoc contexts consisting of arbitrary locale elements. for example
  7193 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  7194 definitions may be given, too); the result is a meta-level rule with
  7195 the context elements being discharged in the obvious way;
  7196 
  7197 * Pure: new proof command 'using' allows to augment currently used
  7198 facts after a goal statement ('using' is syntactically analogous to
  7199 'apply', but acts on the goal's facts only); this allows chained facts
  7200 to be separated into parts given before and after a claim, as in
  7201 ``from a and b have C using d and e <proof>'';
  7202 
  7203 * Pure: renamed "antecedent" case to "rule_context";
  7204 
  7205 * Pure: new 'judgment' command records explicit information about the
  7206 object-logic embedding (used by several tools internally); no longer
  7207 use hard-wired "Trueprop";
  7208 
  7209 * Pure: added 'corollary' command;
  7210 
  7211 * Pure: fixed 'token_translation' command;
  7212 
  7213 * Pure: removed obsolete 'exported' attribute;
  7214 
  7215 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  7216 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  7217 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  7218 
  7219 * Pure: method 'atomize' presents local goal premises as object-level
  7220 statements (atomic meta-level propositions); setup controlled via
  7221 rewrite rules declarations of 'atomize' attribute; example
  7222 application: 'induct' method with proper rule statements in improper
  7223 proof *scripts*;
  7224 
  7225 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  7226 now consider the syntactic context of assumptions, giving a better
  7227 chance to get type-inference of the arguments right (this is
  7228 especially important for locales);
  7229 
  7230 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  7231 mode;
  7232 
  7233 * Pure/obtain: the formal conclusion "thesis", being marked as
  7234 ``internal'', may no longer be reference directly in the text;
  7235 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  7236 situations;
  7237 
  7238 * Pure: generic 'sym' attribute which declares a rule both as pure
  7239 'elim?' and for the 'symmetric' operation;
  7240 
  7241 * Pure: marginal comments ``--'' may now occur just anywhere in the
  7242 text; the fixed correlation with particular command syntax has been
  7243 discontinued;
  7244 
  7245 * Pure: new method 'rules' is particularly well-suited for proof
  7246 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  7247 but often produces more compact proof terms with less detours;
  7248 
  7249 * Pure/Provers/classical: simplified integration with pure rule
  7250 attributes and methods; the classical "intro?/elim?/dest?"
  7251 declarations coincide with the pure ones; the "rule" method no longer
  7252 includes classically swapped intros; "intro" and "elim" methods no
  7253 longer pick rules from the context; also got rid of ML declarations
  7254 AddXIs/AddXEs/AddXDs; all of this has some potential for
  7255 INCOMPATIBILITY;
  7256 
  7257 * Provers/classical: attribute 'swapped' produces classical inversions
  7258 of introduction rules;
  7259 
  7260 * Provers/simplifier: 'simplified' attribute may refer to explicit
  7261 rules instead of full simplifier context; 'iff' attribute handles
  7262 conditional rules;
  7263 
  7264 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  7265 
  7266 * HOL: 'recdef' now fails on unfinished automated proofs, use
  7267 "(permissive)" option to recover old behavior;
  7268 
  7269 * HOL: 'inductive' no longer features separate (collective) attributes
  7270 for 'intros' (was found too confusing);
  7271 
  7272 * HOL: properly declared induction rules less_induct and
  7273 wf_induct_rule;
  7274 
  7275 
  7276 *** HOL ***
  7277 
  7278 * HOL: moved over to sane numeral syntax; the new policy is as
  7279 follows:
  7280 
  7281   - 0 and 1 are polymorphic constants, which are defined on any
  7282   numeric type (nat, int, real etc.);
  7283 
  7284   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  7285   binary representation internally;
  7286 
  7287   - type nat has special constructor Suc, and generally prefers Suc 0
  7288   over 1::nat and Suc (Suc 0) over 2::nat;
  7289 
  7290 This change may cause significant problems of INCOMPATIBILITY; here
  7291 are some hints on converting existing sources:
  7292 
  7293   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  7294   entities, so expressions involving "-" (unary or binary minus) need
  7295   to be spaced properly;
  7296 
  7297   - existing occurrences of "1" may need to be constraint "1::nat" or
  7298   even replaced by Suc 0; similar for old "2";
  7299 
  7300   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  7301 
  7302   - remove all special provisions on numerals in proofs;
  7303 
  7304 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  7305 representation (depends on bin_arith_simps in the default context);
  7306 
  7307 * HOL: symbolic syntax for x^2 (numeral 2);
  7308 
  7309 * HOL: the class of all HOL types is now called "type" rather than
  7310 "term"; INCOMPATIBILITY, need to adapt references to this type class
  7311 in axclass/classes, instance/arities, and (usually rare) occurrences
  7312 in typings (of consts etc.); internally the class is called
  7313 "HOL.type", ML programs should refer to HOLogic.typeS;
  7314 
  7315 * HOL/record package improvements:
  7316   - new derived operations "fields" to build a partial record section,
  7317     "extend" to promote a fixed record to a record scheme, and
  7318     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  7319     declared as simp by default;
  7320   - shared operations ("more", "fields", etc.) now need to be always
  7321     qualified) --- potential INCOMPATIBILITY;
  7322   - removed "make_scheme" operations (use "make" with "extend") --
  7323     INCOMPATIBILITY;
  7324   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  7325   - provides cases/induct rules for use with corresponding Isar
  7326     methods (for concrete records, record schemes, concrete more
  7327     parts, and schematic more parts -- in that order);
  7328   - internal definitions directly based on a light-weight abstract
  7329     theory of product types over typedef rather than datatype;
  7330 
  7331 * HOL: generic code generator for generating executable ML code from
  7332 specifications; specific support for HOL constructs such as inductive
  7333 datatypes and sets, as well as recursive functions; can be invoked
  7334 via 'generate_code' theory section;
  7335 
  7336 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  7337 
  7338 * HOL: consolidated and renamed several theories.  In particular:
  7339         Ord.thy has been absorbed into HOL.thy
  7340         String.thy has been absorbed into List.thy
  7341 
  7342 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  7343 (beware of argument permutation!);
  7344 
  7345 * HOL: linorder_less_split superseded by linorder_cases;
  7346 
  7347 * HOL/List: "nodups" renamed to "distinct";
  7348 
  7349 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  7350 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  7351   - Ex_def has changed, now need to use some_eq_ex
  7352 
  7353 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  7354 in this (rare) case use:
  7355 
  7356   delSWrapper "split_all_tac"
  7357   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  7358 
  7359 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  7360 MAY FAIL;
  7361 
  7362 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  7363 Isabelle's type classes, ^ on functions and relations has too general
  7364 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  7365 necessary to attach explicit type constraints;
  7366 
  7367 * HOL/Relation: the prefix name of the infix "O" has been changed from
  7368 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  7369 renamed accordingly (eg "compI" -> "rel_compI").
  7370 
  7371 * HOL: syntax translations now work properly with numerals and records
  7372 expressions;
  7373 
  7374 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  7375 of "lam" -- INCOMPATIBILITY;
  7376 
  7377 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  7378 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  7379 renamed "Product_Type.unit";
  7380 
  7381 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  7382 
  7383 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  7384 the "cases" method);
  7385 
  7386 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  7387 Florian Kammller);
  7388 
  7389 * HOL/IMP: updated and converted to new-style theory format; several
  7390 parts turned into readable document, with proper Isar proof texts and
  7391 some explanations (by Gerwin Klein);
  7392 
  7393 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  7394 
  7395 * HOL-Hyperreal is now a logic image;
  7396 
  7397 
  7398 *** HOLCF ***
  7399 
  7400 * Isar: consts/constdefs supports mixfix syntax for continuous
  7401 operations;
  7402 
  7403 * Isar: domain package adapted to new-style theory format, e.g. see
  7404 HOLCF/ex/Dnat.thy;
  7405 
  7406 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7407 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7408 lift.induct_tac, always use UU instead of Undef;
  7409 
  7410 * HOLCF/IMP: updated and converted to new-style theory;
  7411 
  7412 
  7413 *** ZF ***
  7414 
  7415 * Isar: proper integration of logic-specific tools and packages,
  7416 including theory commands '(co)inductive', '(co)datatype',
  7417 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7418 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7419 
  7420 * theory Main no longer includes AC; for the Axiom of Choice, base
  7421 your theory on Main_ZFC;
  7422 
  7423 * the integer library now covers quotients and remainders, with many
  7424 laws relating division to addition, multiplication, etc.;
  7425 
  7426 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7427 typeless version of the formalism;
  7428 
  7429 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7430 format;
  7431 
  7432 * ZF/Induct: new directory for examples of inductive definitions,
  7433 including theory Multiset for multiset orderings; converted to
  7434 new-style theory format;
  7435 
  7436 * ZF: many new theorems about lists, ordinals, etc.;
  7437 
  7438 
  7439 *** General ***
  7440 
  7441 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7442 variable proof controls level of detail: 0 = no proofs (only oracle
  7443 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7444 also ref manual for further ML interfaces;
  7445 
  7446 * Pure/axclass: removed obsolete ML interface
  7447 goal_subclass/goal_arity;
  7448 
  7449 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7450 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7451 separate tokens, so expressions involving minus need to be spaced
  7452 properly;
  7453 
  7454 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7455 rather than "infixl" or "infixr";
  7456 
  7457 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7458 sort constraint specifications in type inference; e.g. "x::_::foo"
  7459 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7460 type variable);
  7461 
  7462 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7463 control output of nested => (types); the default behavior is
  7464 "type_brackets";
  7465 
  7466 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7467 tokens into AST constants;
  7468 
  7469 * Pure/syntax: prefer later declarations of translations and print
  7470 translation functions; potential INCOMPATIBILITY: need to reverse
  7471 multiple declarations for same syntax element constant;
  7472 
  7473 * Pure/show_hyps reset by default (in accordance to existing Isar
  7474 practice);
  7475 
  7476 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7477 addSafter;
  7478 
  7479 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7480 as well;
  7481 
  7482 * system: tested support for MacOS X; should be able to get Isabelle +
  7483 Proof General to work in a plain Terminal after installing Poly/ML
  7484 (e.g. from the Isabelle distribution area) and GNU bash alone
  7485 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7486 support requires further installations, e.g. from
  7487 http://fink.sourceforge.net/);
  7488 
  7489 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7490 
  7491 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7492 of 40 MB), cf. ML_OPTIONS;
  7493 
  7494 * system: Proof General keywords specification is now part of the
  7495 Isabelle distribution (see etc/isar-keywords.el);
  7496 
  7497 * system: support for persistent Proof General sessions (refrain from
  7498 outdating all loaded theories on startup); user may create writable
  7499 logic images like this: ``isabelle -q HOL Test'';
  7500 
  7501 * system: smart selection of Isabelle process versus Isabelle
  7502 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7503 run both "isabelle" and "Isabelle" even if file names are badly
  7504 damaged (executable inspects the case of the first letter of its own
  7505 name); added separate "isabelle-process" and "isabelle-interface";
  7506 
  7507 * system: refrain from any attempt at filtering input streams; no
  7508 longer support ``8bit'' encoding of old isabelle font, instead proper
  7509 iso-latin characters may now be used; the related isatools
  7510 "symbolinput" and "nonascii" have disappeared as well;
  7511 
  7512 * system: removed old "xterm" interface (the print modes "xterm" and
  7513 "xterm_color" are still available for direct use in a suitable
  7514 terminal);
  7515 
  7516 
  7517 
  7518 New in Isabelle99-2 (February 2001)
  7519 -----------------------------------
  7520 
  7521 *** Overview of INCOMPATIBILITIES ***
  7522 
  7523 * HOL: please note that theories in the Library and elsewhere often use the
  7524 new-style (Isar) format; to refer to their theorems in an ML script you must
  7525 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  7526 
  7527 * HOL: inductive package no longer splits induction rule aggressively,
  7528 but only as far as specified by the introductions given; the old
  7529 format may be recovered via ML function complete_split_rule or attribute
  7530 'split_rule (complete)';
  7531 
  7532 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  7533 gfp_Tarski to gfp_unfold;
  7534 
  7535 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  7536 
  7537 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  7538 relation); infix "^^" has been renamed "``"; infix "``" has been
  7539 renamed "`"; "univalent" has been renamed "single_valued";
  7540 
  7541 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  7542 operation;
  7543 
  7544 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  7545 
  7546 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  7547 
  7548 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  7549 consequence, it is no longer monotonic wrt. the local goal context
  7550 (which is now passed through the inductive cases);
  7551 
  7552 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  7553 \<gg> to \<ggreater>;
  7554 
  7555 
  7556 *** Document preparation ***
  7557 
  7558 * \isabellestyle{NAME} selects version of Isabelle output (currently
  7559 available: are "it" for near math-mode best-style output, "sl" for
  7560 slanted text style, and "tt" for plain type-writer; if no
  7561 \isabellestyle command is given, output is according to slanted
  7562 type-writer);
  7563 
  7564 * support sub/super scripts (for single symbols only), input syntax is
  7565 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  7566 
  7567 * some more standard symbols; see Appendix A of the system manual for
  7568 the complete list of symbols defined in isabellesym.sty;
  7569 
  7570 * improved isabelle style files; more abstract symbol implementation
  7571 (should now use \isamath{...} and \isatext{...} in custom symbol
  7572 definitions);
  7573 
  7574 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  7575 state; Note that presentation of goal states does not conform to
  7576 actual human-readable proof documents.  Please do not include goal
  7577 states into document output unless you really know what you are doing!
  7578 
  7579 * proper indentation of antiquoted output with proportional LaTeX
  7580 fonts;
  7581 
  7582 * no_document ML operator temporarily disables LaTeX document
  7583 generation;
  7584 
  7585 * isatool unsymbolize tunes sources for plain ASCII communication;
  7586 
  7587 
  7588 *** Isar ***
  7589 
  7590 * Pure: Isar now suffers initial goal statements to contain unbound
  7591 schematic variables (this does not conform to actual readable proof
  7592 documents, due to unpredictable outcome and non-compositional proof
  7593 checking); users who know what they are doing may use schematic goals
  7594 for Prolog-style synthesis of proven results;
  7595 
  7596 * Pure: assumption method (an implicit finishing) now handles actual
  7597 rules as well;
  7598 
  7599 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  7600 initial goal, declare "that" only as Pure intro (only for single
  7601 steps); the "that" rule assumption may now be involved in implicit
  7602 finishing, thus ".." becomes a feasible for trivial obtains;
  7603 
  7604 * Pure: default proof step now includes 'intro_classes'; thus trivial
  7605 instance proofs may be performed by "..";
  7606 
  7607 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  7608 statements as well;
  7609 
  7610 * Pure: more robust selection of calculational rules;
  7611 
  7612 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  7613 rule (as well as the assumption rule);
  7614 
  7615 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  7616 lemmas, using the graph browser tool;
  7617 
  7618 * Pure: predict failure of "show" in interactive mode;
  7619 
  7620 * Pure: 'thms_containing' now takes actual terms as arguments;
  7621 
  7622 * HOL: improved method 'induct' --- now handles non-atomic goals
  7623 (potential INCOMPATIBILITY); tuned error handling;
  7624 
  7625 * HOL: cases and induct rules now provide explicit hints about the
  7626 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  7627 any remaining facts are inserted into the goal verbatim;
  7628 
  7629 * HOL: local contexts (aka cases) may now contain term bindings as
  7630 well; the 'cases' and 'induct' methods new provide a ?case binding for
  7631 the result to be shown in each case;
  7632 
  7633 * HOL: added 'recdef_tc' command;
  7634 
  7635 * isatool convert assists in eliminating legacy ML scripts;
  7636 
  7637 
  7638 *** HOL ***
  7639 
  7640 * HOL/Library: a collection of generic theories to be used together
  7641 with main HOL; the theory loader path already includes this directory
  7642 by default; the following existing theories have been moved here:
  7643 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  7644 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  7645 
  7646 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  7647 modelling and verification task performed in Isabelle/HOL +
  7648 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  7649 
  7650 * HOL/Algebra: special summation operator SUM no longer exists, it has
  7651 been replaced by setsum; infix 'assoc' now has priority 50 (like
  7652 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  7653 'domain', this makes the theory consistent with mathematical
  7654 literature;
  7655 
  7656 * HOL basics: added overloaded operations "inverse" and "divide"
  7657 (infix "/"), syntax for generic "abs" operation, generic summation
  7658 operator \<Sum>;
  7659 
  7660 * HOL/typedef: simplified package, provide more useful rules (see also
  7661 HOL/subset.thy);
  7662 
  7663 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  7664 now expressed as a proper nested rule (old-style tactic scripts may
  7665 require atomize_strip_tac to cope with non-atomic premises);
  7666 
  7667 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  7668 to "split_conv" (old name still available for compatibility);
  7669 
  7670 * HOL: improved concrete syntax for strings (e.g. allows translation
  7671 rules with string literals);
  7672 
  7673 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  7674  and Fleuriot's mechanization of analysis, including the transcendental
  7675  functions for the reals;
  7676 
  7677 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  7678 
  7679 
  7680 *** CTT ***
  7681 
  7682 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  7683 "lam" is displayed as TWO lambda-symbols
  7684 
  7685 * CTT: theory Main now available, containing everything (that is, Bool
  7686 and Arith);
  7687 
  7688 
  7689 *** General ***
  7690 
  7691 * Pure: the Simplifier has been implemented properly as a derived rule
  7692 outside of the actual kernel (at last!); the overall performance
  7693 penalty in practical applications is about 50%, while reliability of
  7694 the Isabelle inference kernel has been greatly improved;
  7695 
  7696 * print modes "brackets" and "no_brackets" control output of nested =>
  7697 (types) and ==> (props); the default behaviour is "brackets";
  7698 
  7699 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7700 as assumptions as well;
  7701 
  7702 * system: support Poly/ML 4.0;
  7703 
  7704 * system: isatool install handles KDE version 1 or 2;
  7705 
  7706 
  7707 
  7708 New in Isabelle99-1 (October 2000)
  7709 ----------------------------------
  7710 
  7711 *** Overview of INCOMPATIBILITIES ***
  7712 
  7713 * HOL: simplification of natural numbers is much changed; to partly
  7714 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7715 issue the following ML commands:
  7716 
  7717   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7718   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7719 
  7720 * HOL: simplification no longer dives into case-expressions; this is
  7721 controlled by "t.weak_case_cong" for each datatype t;
  7722 
  7723 * HOL: nat_less_induct renamed to less_induct;
  7724 
  7725 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7726 fixsome to patch .thy and .ML sources automatically;
  7727 
  7728   select_equality  -> some_equality
  7729   select_eq_Ex     -> some_eq_ex
  7730   selectI2EX       -> someI2_ex
  7731   selectI2         -> someI2
  7732   selectI          -> someI
  7733   select1_equality -> some1_equality
  7734   Eps_sym_eq       -> some_sym_eq_trivial
  7735   Eps_eq           -> some_eq_trivial
  7736 
  7737 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7738 
  7739 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7740 instead);
  7741 
  7742 * HOL: the recursion equations generated by 'recdef' are now called
  7743 f.simps instead of f.rules;
  7744 
  7745 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7746 
  7747 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7748 sometimes be needed;
  7749 
  7750 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7751 
  7752 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7753 
  7754 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7755 product is now "<*>" instead of "Times"; the lexicographic product is
  7756 now "<*lex*>" instead of "**";
  7757 
  7758 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7759 of main HOL, but was unused); better use HOL's datatype package;
  7760 
  7761 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7762 the old syntax may be recovered as follows:
  7763 
  7764   syntax (symbols)
  7765     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7766       (infixl "\\<oplus>" 100)
  7767 
  7768 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7769 
  7770 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7771 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7772 internally;
  7773 
  7774 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7775 changed from A/r to A//r;
  7776 
  7777 * ZF: new treatment of arithmetic (nat & int) may break some old
  7778 proofs;
  7779 
  7780 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7781 rulify -> rule_format, elimify -> elim_format, ...);
  7782 
  7783 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7784 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7785 should have to change intro!! to intro? only); replaced "delrule" by
  7786 "rule del";
  7787 
  7788 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7789 
  7790 * Provers: strengthened force_tac by using new first_best_tac;
  7791 
  7792 * LaTeX document preparation: several changes of isabelle.sty (see
  7793 lib/texinputs);
  7794 
  7795 
  7796 *** Document preparation ***
  7797 
  7798 * formal comments (text blocks etc.) in new-style theories may now
  7799 contain antiquotations of thm/prop/term/typ/text to be presented
  7800 according to latex print mode; concrete syntax is like this:
  7801 @{term[show_types] "f(x) = a + x"};
  7802 
  7803 * isatool mkdir provides easy setup of Isabelle session directories,
  7804 including proper document sources;
  7805 
  7806 * generated LaTeX sources are now deleted after successful run
  7807 (isatool document -c); may retain a copy somewhere else via -D option
  7808 of isatool usedir;
  7809 
  7810 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7811 style files, achieving self-contained LaTeX sources and simplifying
  7812 LaTeX debugging;
  7813 
  7814 * old-style theories now produce (crude) LaTeX output as well;
  7815 
  7816 * browser info session directories are now self-contained (may be put
  7817 on WWW server seperately); improved graphs of nested sessions; removed
  7818 graph for 'all sessions';
  7819 
  7820 * several improvements in isabelle style files; \isabellestyle{it}
  7821 produces fake math mode output; \isamarkupheader is now \section by
  7822 default; see lib/texinputs/isabelle.sty etc.;
  7823 
  7824 
  7825 *** Isar ***
  7826 
  7827 * Isar/Pure: local results and corresponding term bindings are now
  7828 subject to Hindley-Milner polymorphism (similar to ML); this
  7829 accommodates incremental type-inference very nicely;
  7830 
  7831 * Isar/Pure: new derived language element 'obtain' supports
  7832 generalized existence reasoning;
  7833 
  7834 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7835 support accumulation of results, without applying any rules yet;
  7836 useful to collect intermediate results without explicit name
  7837 references, and for use with transitivity rules with more than 2
  7838 premises;
  7839 
  7840 * Isar/Pure: scalable support for case-analysis type proofs: new
  7841 'case' language element refers to local contexts symbolically, as
  7842 produced by certain proof methods; internally, case names are attached
  7843 to theorems as "tags";
  7844 
  7845 * Isar/Pure: theory command 'hide' removes declarations from
  7846 class/type/const name spaces;
  7847 
  7848 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7849 indicate potential overloading;
  7850 
  7851 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7852 
  7853 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7854 "{a,b,c}" instead of {a,b,c};
  7855 
  7856 * Isar/Pure now provides its own version of intro/elim/dest
  7857 attributes; useful for building new logics, but beware of confusion
  7858 with the version in Provers/classical;
  7859 
  7860 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7861 case name 'antecedent';
  7862 
  7863 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7864 to the current context is now done automatically);
  7865 
  7866 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7867 for definining proof methods in ML;
  7868 
  7869 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7870 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7871 most cases, one should have to change intro!! to intro? only);
  7872 replaced "delrule" by "rule del";
  7873 
  7874 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7875 'symmetric' attribute (the latter supercedes [RS sym]);
  7876 
  7877 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7878 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7879 well (including splits);
  7880 
  7881 * Isar/Provers: Simplifier and Classical methods now support all kind
  7882 of modifiers used in the past, including 'cong', 'iff', etc.
  7883 
  7884 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7885 of Simplifier and Classical reasoner);
  7886 
  7887 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7888 now support named cases; major packages (inductive, datatype, primrec,
  7889 recdef) support case names and properly name parameters;
  7890 
  7891 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7892 monotonicity conditions are extracted to be proven at end of
  7893 calculations;
  7894 
  7895 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7896 method anyway;
  7897 
  7898 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7899 split_if split_if_asm; datatype package provides theorems foo.splits =
  7900 foo.split foo.split_asm for each datatype;
  7901 
  7902 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7903 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7904 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  7905 use "(cases (simplified))" method in proper proof texts);
  7906 
  7907 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  7908 
  7909 * Isar: names of theorems etc. may be natural numbers as well;
  7910 
  7911 * Isar: 'pr' command: optional arguments for goals_limit and
  7912 ProofContext.prems_limit; no longer prints theory contexts, but only
  7913 proof states;
  7914 
  7915 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  7916 additional print modes to be specified; e.g. "pr(latex)" will print
  7917 proof state according to the Isabelle LaTeX style;
  7918 
  7919 * Isar: improved support for emulating tactic scripts, including proof
  7920 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  7921 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  7922 (for HOL datatypes);
  7923 
  7924 * Isar: simplified (more robust) goal selection of proof methods: 1st
  7925 goal, all goals, or explicit goal specifier (tactic emulation); thus
  7926 'proof method scripts' have to be in depth-first order;
  7927 
  7928 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  7929 
  7930 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  7931 should instead use individual commands for printing items
  7932 (print_commands, print_methods etc.);
  7933 
  7934 * Isar: added 'nothing' --- the empty list of theorems;
  7935 
  7936 
  7937 *** HOL ***
  7938 
  7939 * HOL/MicroJava: formalization of a fragment of Java, together with a
  7940 corresponding virtual machine and a specification of its bytecode
  7941 verifier and a lightweight bytecode verifier, including proofs of
  7942 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  7943 Cornelia Pusch (see also the homepage of project Bali at
  7944 http://isabelle.in.tum.de/Bali/);
  7945 
  7946 * HOL/Algebra: new theory of rings and univariate polynomials, by
  7947 Clemens Ballarin;
  7948 
  7949 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  7950 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  7951 Rasmussen;
  7952 
  7953 * HOL/Lattice: fundamental concepts of lattice theory and order
  7954 structures, including duals, properties of bounds versus algebraic
  7955 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  7956 Theorem for complete lattices etc.; may also serve as a demonstration
  7957 for abstract algebraic reasoning using axiomatic type classes, and
  7958 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  7959 
  7960 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  7961 von Oheimb;
  7962 
  7963 * HOL/IMPP: extension of IMP with local variables and mutually
  7964 recursive procedures, by David von Oheimb;
  7965 
  7966 * HOL/Lambda: converted into new-style theory and document;
  7967 
  7968 * HOL/ex/Multiquote: example of multiple nested quotations and
  7969 anti-quotations -- basically a generalized version of de-Bruijn
  7970 representation; very useful in avoiding lifting of operations;
  7971 
  7972 * HOL/record: added general record equality rule to simpset; fixed
  7973 select-update simplification procedure to handle extended records as
  7974 well; admit "r" as field name;
  7975 
  7976 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  7977 other numeric types and also as the identity of groups, rings, etc.;
  7978 
  7979 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  7980 Types nat and int belong to this axclass;
  7981 
  7982 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  7983    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  7984    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  7985   two terms #m*u and #n*u are replaced by #(m+n)*u
  7986     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  7987   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  7988     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  7989 
  7990 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  7991 powerful prover for predicate logic but knows nothing of clasets; see
  7992 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  7993 
  7994 * HOL: new version of "case_tac" subsumes both boolean case split and
  7995 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  7996 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  7997 
  7998 * HOL: simplification no longer dives into case-expressions: only the
  7999 selector expression is simplified, but not the remaining arms; to
  8000 enable full simplification of case-expressions for datatype t, you may
  8001 remove t.weak_case_cong from the simpset, either globally (Delcongs
  8002 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  8003 
  8004 * HOL/recdef: the recursion equations generated by 'recdef' for
  8005 function 'f' are now called f.simps instead of f.rules; if all
  8006 termination conditions are proved automatically, these simplification
  8007 rules are added to the simpset, as in primrec; rules may be named
  8008 individually as well, resulting in a separate list of theorems for
  8009 each equation;
  8010 
  8011 * HOL/While is a new theory that provides a while-combinator. It
  8012 permits the definition of tail-recursive functions without the
  8013 provision of a termination measure. The latter is necessary once the
  8014 invariant proof rule for while is applied.
  8015 
  8016 * HOL: new (overloaded) notation for the set of elements below/above
  8017 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  8018 
  8019 * HOL: theorems impI, allI, ballI bound as "strip";
  8020 
  8021 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  8022 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  8023 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  8024 
  8025 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  8026 
  8027 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  8028 main HOL, but was unused);
  8029 
  8030 * HOL: fewer consts declared as global (e.g. have to refer to
  8031 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  8032 
  8033 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  8034 in case of overlap with user translations (e.g. judgements over
  8035 tuples); (note that the underlying logical represenation is still
  8036 bogus);
  8037 
  8038 
  8039 *** ZF ***
  8040 
  8041 * ZF: simplification automatically cancels common terms in arithmetic
  8042 expressions over nat and int;
  8043 
  8044 * ZF: new treatment of nat to minimize type-checking: all operators
  8045 coerce their operands to a natural number using the function natify,
  8046 making the algebraic laws unconditional;
  8047 
  8048 * ZF: as above, for int: operators coerce their operands to an integer
  8049 using the function intify;
  8050 
  8051 * ZF: the integer library now contains many of the usual laws for the
  8052 orderings, including $<=, and monotonicity laws for $+ and $*;
  8053 
  8054 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  8055 simplification;
  8056 
  8057 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  8058 to the simplifier and classical reasoner simultaneously;
  8059 
  8060 
  8061 *** General ***
  8062 
  8063 * Provers: blast_tac now handles actual object-logic rules as
  8064 assumptions; note that auto_tac uses blast_tac internally as well;
  8065 
  8066 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  8067 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  8068 
  8069 * Provers: delrules now handles destruct rules as well (no longer need
  8070 explicit make_elim);
  8071 
  8072 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  8073   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8074 use instead the strong form,
  8075   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  8076 in HOL, FOL and ZF the function cla_make_elim will create such rules
  8077 from destruct-rules;
  8078 
  8079 * Provers: Simplifier.easy_setup provides a fast path to basic
  8080 Simplifier setup for new object-logics;
  8081 
  8082 * Pure: AST translation rules no longer require constant head on LHS;
  8083 
  8084 * Pure: improved name spaces: ambiguous output is qualified; support
  8085 for hiding of names;
  8086 
  8087 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  8088 XSYMBOL_HOME; no longer need to do manual configuration in most
  8089 situations;
  8090 
  8091 * system: compression of ML heaps images may now be controlled via -c
  8092 option of isabelle and isatool usedir (currently only observed by
  8093 Poly/ML);
  8094 
  8095 * system: isatool installfonts may handle X-Symbol fonts as well (very
  8096 useful for remote X11);
  8097 
  8098 * system: provide TAGS file for Isabelle sources;
  8099 
  8100 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  8101 order;
  8102 
  8103 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  8104 timing flag supersedes proof_timing and Toplevel.trace;
  8105 
  8106 * ML: new combinators |>> and |>>> for incremental transformations
  8107 with secondary results (e.g. certain theory extensions):
  8108 
  8109 * ML: PureThy.add_defs gets additional argument to indicate potential
  8110 overloading (usually false);
  8111 
  8112 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  8113 results;
  8114 
  8115 
  8116 
  8117 New in Isabelle99 (October 1999)
  8118 --------------------------------
  8119 
  8120 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8121 
  8122 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  8123 are no longer simplified.  (This allows the simplifier to unfold recursive
  8124 functional programs.)  To restore the old behaviour, declare
  8125 
  8126     Delcongs [if_weak_cong];
  8127 
  8128 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  8129 complement;
  8130 
  8131 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  8132 
  8133 * HOL/datatype: mutual_induct_tac no longer exists --
  8134   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  8135 
  8136 * HOL/typedef: fixed type inference for representing set; type
  8137 arguments now have to occur explicitly on the rhs as type constraints;
  8138 
  8139 * ZF: The con_defs part of an inductive definition may no longer refer
  8140 to constants declared in the same theory;
  8141 
  8142 * HOL, ZF: the function mk_cases, generated by the inductive
  8143 definition package, has lost an argument.  To simplify its result, it
  8144 uses the default simpset instead of a supplied list of theorems.
  8145 
  8146 * HOL/List: the constructors of type list are now Nil and Cons;
  8147 
  8148 * Simplifier: the type of the infix ML functions
  8149         setSSolver addSSolver setSolver addSolver
  8150 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  8151 for packaging solvers. A solver is created via
  8152         mk_solver: string -> (thm list -> int -> tactic) -> solver
  8153 where the string argument is only a comment.
  8154 
  8155 
  8156 *** Proof tools ***
  8157 
  8158 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  8159 decision procedure for linear arithmetic. Currently it is used for
  8160 types `nat', `int', and `real' in HOL (see below); it can, should and
  8161 will be instantiated for other types and logics as well.
  8162 
  8163 * The simplifier now accepts rewrite rules with flexible heads, eg
  8164      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  8165   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  8166   matching.
  8167 
  8168 
  8169 *** General ***
  8170 
  8171 * New Isabelle/Isar subsystem provides an alternative to traditional
  8172 tactical theorem proving; together with the ProofGeneral/isar user
  8173 interface it offers an interactive environment for developing human
  8174 readable proof documents (Isar == Intelligible semi-automated
  8175 reasoning); for further information see isatool doc isar-ref,
  8176 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  8177 
  8178 * improved and simplified presentation of theories: better HTML markup
  8179 (including colors), graph views in several sizes; isatool usedir now
  8180 provides a proper interface for user theories (via -P option); actual
  8181 document preparation based on (PDF)LaTeX is available as well (for
  8182 new-style theories only); see isatool doc system for more information;
  8183 
  8184 * native support for Proof General, both for classic Isabelle and
  8185 Isabelle/Isar;
  8186 
  8187 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  8188 using the graph browser tool;
  8189 
  8190 * Isabelle manuals now also available as PDF;
  8191 
  8192 * theory loader rewritten from scratch (may not be fully
  8193 bug-compatible); old loadpath variable has been replaced by show_path,
  8194 add_path, del_path, reset_path functions; new operations such as
  8195 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  8196 isatool doc ref);
  8197 
  8198 * improved isatool install: option -k creates KDE application icon,
  8199 option -p DIR installs standalone binaries;
  8200 
  8201 * added ML_PLATFORM setting (useful for cross-platform installations);
  8202 more robust handling of platform specific ML images for SML/NJ;
  8203 
  8204 * the settings environment is now statically scoped, i.e. it is never
  8205 created again in sub-processes invoked from isabelle, isatool, or
  8206 Isabelle;
  8207 
  8208 * path element specification '~~' refers to '$ISABELLE_HOME';
  8209 
  8210 * in locales, the "assumes" and "defines" parts may be omitted if
  8211 empty;
  8212 
  8213 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  8214 long arrows);
  8215 
  8216 * new print_mode "HTML";
  8217 
  8218 * new flag show_tags controls display of tags of theorems (which are
  8219 basically just comments that may be attached by some tools);
  8220 
  8221 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  8222 mode and goal output format:
  8223 
  8224 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  8225 244c244
  8226 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  8227 ---
  8228 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  8229 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  8230 181c181
  8231 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  8232 ---
  8233 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  8234 
  8235 * function bind_thms stores lists of theorems (cf. bind_thm);
  8236 
  8237 * new shorthand tactics ftac, eatac, datac, fatac;
  8238 
  8239 * qed (and friends) now accept "" as result name; in that case the
  8240 theorem is not stored, but proper checks and presentation of the
  8241 result still apply;
  8242 
  8243 * theorem database now also indexes constants "Trueprop", "all",
  8244 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  8245 
  8246 
  8247 *** HOL ***
  8248 
  8249 ** HOL arithmetic **
  8250 
  8251 * There are now decision procedures for linear arithmetic over nat and
  8252 int:
  8253 
  8254 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  8255 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  8256 are treated as atomic; subformulae not involving type `nat' or `int'
  8257 are ignored; quantified subformulae are ignored unless they are
  8258 positive universal or negative existential. The tactic has to be
  8259 invoked by hand and can be a little bit slow. In particular, the
  8260 running time is exponential in the number of occurrences of `min' and
  8261 `max', and `-' on `nat'.
  8262 
  8263 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  8264 (negated) (in)equalities among the premises and the conclusion into
  8265 account (i.e. no compound formulae) and does not know about `min' and
  8266 `max', and `-' on `nat'. It is fast and is used automatically by the
  8267 simplifier.
  8268 
  8269 NB: At the moment, these decision procedures do not cope with mixed
  8270 nat/int formulae where the two parts interact, such as `m < n ==>
  8271 int(m) < int(n)'.
  8272 
  8273 * HOL/Numeral provides a generic theory of numerals (encoded
  8274 efficiently as bit strings); setup for types nat/int/real is in place;
  8275 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  8276 int, existing theories and proof scripts may require a few additional
  8277 type constraints;
  8278 
  8279 * integer division and remainder can now be performed on constant
  8280 arguments;
  8281 
  8282 * many properties of integer multiplication, division and remainder
  8283 are now available;
  8284 
  8285 * An interface to the Stanford Validity Checker (SVC) is available through the
  8286 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  8287 are proved automatically.  SVC must be installed separately, and its results
  8288 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  8289 invocation of the underlying oracle).  For SVC see
  8290   http://verify.stanford.edu/SVC
  8291 
  8292 * IsaMakefile: the HOL-Real target now builds an actual image;
  8293 
  8294 
  8295 ** HOL misc **
  8296 
  8297 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  8298 (in Isabelle/Isar) -- by Gertrud Bauer;
  8299 
  8300 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  8301 analysis for assembly languages with subtypes;
  8302 
  8303 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  8304 -- avoids syntactic ambiguities and treats state, transition, and
  8305 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  8306 changed syntax and (many) tactics;
  8307 
  8308 * HOL/inductive: Now also handles more general introduction rules such
  8309   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  8310   theorems are now maintained within the theory (maintained via the
  8311   "mono" attribute);
  8312 
  8313 * HOL/datatype: Now also handles arbitrarily branching datatypes
  8314   (using function types) such as
  8315 
  8316   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  8317 
  8318 * HOL/record: record_simproc (part of the default simpset) takes care
  8319 of selectors applied to updated records; record_split_tac is no longer
  8320 part of the default claset; update_defs may now be removed from the
  8321 simpset in many cases; COMPATIBILITY: old behavior achieved by
  8322 
  8323   claset_ref () := claset() addSWrapper record_split_wrapper;
  8324   Delsimprocs [record_simproc]
  8325 
  8326 * HOL/typedef: fixed type inference for representing set; type
  8327 arguments now have to occur explicitly on the rhs as type constraints;
  8328 
  8329 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  8330 names rather than an ML expression;
  8331 
  8332 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  8333 supplied later.  Program schemes can be defined, such as
  8334     "While B C s = (if B s then While B C (C s) else s)"
  8335 where the well-founded relation can be chosen after B and C have been given.
  8336 
  8337 * HOL/List: the constructors of type list are now Nil and Cons;
  8338 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  8339 course, ML tools referring to List.list.op # etc. have to be adapted;
  8340 
  8341 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  8342 disabled by default; run isabelle with option -m HOL to get back to
  8343 the original Gordon/HOL-style output;
  8344 
  8345 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  8346 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  8347 
  8348 * HOL basic syntax simplified (more orthogonal): all variants of
  8349 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  8350 Eps operator is provided as well: "SOME x. P[x]";
  8351 
  8352 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  8353 
  8354 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  8355 thus available for user theories;
  8356 
  8357 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  8358 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  8359 time;
  8360 
  8361 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  8362 several times and then mp;
  8363 
  8364 
  8365 *** LK ***
  8366 
  8367 * the notation <<...>> is now available as a notation for sequences of
  8368 formulas;
  8369 
  8370 * the simplifier is now installed
  8371 
  8372 * the axiom system has been generalized (thanks to Soren Heilmann)
  8373 
  8374 * the classical reasoner now has a default rule database
  8375 
  8376 
  8377 *** ZF ***
  8378 
  8379 * new primrec section allows primitive recursive functions to be given
  8380 directly (as in HOL) over datatypes and the natural numbers;
  8381 
  8382 * new tactics induct_tac and exhaust_tac for induction (or case
  8383 analysis) over datatypes and the natural numbers;
  8384 
  8385 * the datatype declaration of type T now defines the recursor T_rec;
  8386 
  8387 * simplification automatically does freeness reasoning for datatype
  8388 constructors;
  8389 
  8390 * automatic type-inference, with AddTCs command to insert new
  8391 type-checking rules;
  8392 
  8393 * datatype introduction rules are now added as Safe Introduction rules
  8394 to the claset;
  8395 
  8396 * the syntax "if P then x else y" is now available in addition to
  8397 if(P,x,y);
  8398 
  8399 
  8400 *** Internal programming interfaces ***
  8401 
  8402 * tuned simplifier trace output; new flag debug_simp;
  8403 
  8404 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8405 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8406 
  8407 * AxClass.axclass_tac lost the theory argument;
  8408 
  8409 * tuned current_goals_markers semantics: begin / end goal avoids
  8410 printing empty lines;
  8411 
  8412 * removed prs and prs_fn hook, which was broken because it did not
  8413 include \n in its semantics, forcing writeln to add one
  8414 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8415 string -> unit if you really want to output text without newline;
  8416 
  8417 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8418 plain output, interface builders may have to enable 'isabelle_font'
  8419 mode to get Isabelle font glyphs as before;
  8420 
  8421 * refined token_translation interface; INCOMPATIBILITY: output length
  8422 now of type real instead of int;
  8423 
  8424 * theory loader actions may be traced via new ThyInfo.add_hook
  8425 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8426 your own database of information attached to *whole* theories -- as
  8427 opposed to intra-theory data slots offered via TheoryDataFun;
  8428 
  8429 * proper handling of dangling sort hypotheses (at last!);
  8430 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8431 extra sort hypotheses that can be witnessed from the type signature;
  8432 the force_strip_shyps flag is gone, any remaining shyps are simply
  8433 left in the theorem (with a warning issued by strip_shyps_warning);
  8434 
  8435 
  8436 
  8437 New in Isabelle98-1 (October 1998)
  8438 ----------------------------------
  8439 
  8440 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8441 
  8442 * several changes of automated proof tools;
  8443 
  8444 * HOL: major changes to the inductive and datatype packages, including
  8445 some minor incompatibilities of theory syntax;
  8446 
  8447 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8448 called `inj_on';
  8449 
  8450 * HOL: removed duplicate thms in Arith:
  8451   less_imp_add_less  should be replaced by  trans_less_add1
  8452   le_imp_add_le      should be replaced by  trans_le_add1
  8453 
  8454 * HOL: unary minus is now overloaded (new type constraints may be
  8455 required);
  8456 
  8457 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8458 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8459 now taken as an integer constant.
  8460 
  8461 * Pure: ML function 'theory_of' renamed to 'theory';
  8462 
  8463 
  8464 *** Proof tools ***
  8465 
  8466 * Simplifier:
  8467   1. Asm_full_simp_tac is now more aggressive.
  8468      1. It will sometimes reorient premises if that increases their power to
  8469         simplify.
  8470      2. It does no longer proceed strictly from left to right but may also
  8471         rotate premises to achieve further simplification.
  8472      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8473      old Asm_full_simp_tac in that it does not rotate premises.
  8474   2. The simplifier now knows a little bit about nat-arithmetic.
  8475 
  8476 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8477 allows for selected deletion of wrappers, by introduction of names for
  8478 wrapper functionals.  This implies that addbefore, addSbefore,
  8479 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8480 and that adding two tactics with the same name overwrites the first
  8481 one (emitting a warning).
  8482   type wrapper = (int -> tactic) -> (int -> tactic)
  8483   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8484   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8485   delWrapper, delSWrapper: claset *  string            -> claset
  8486   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8487 
  8488 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8489 semantics; addbefore now affects only the unsafe part of step_tac
  8490 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8491 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8492 by Force_tac;
  8493 
  8494 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8495 compWrapper; added safe wrapper (and access functions for it);
  8496 
  8497 * HOL/split_all_tac is now much faster and fails if there is nothing
  8498 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8499 and the names of the automatically generated variables have changed.
  8500 split_all_tac has moved within claset() from unsafe wrappers to safe
  8501 wrappers, which means that !!-bound variables are split much more
  8502 aggressively, and safe_tac and clarify_tac now split such variables.
  8503 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8504 Note: the same holds for record_split_tac, which does the job of
  8505 split_all_tac for record fields.
  8506 
  8507 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8508 permanently to the default simpset using Addsplits just like
  8509 Addsimps. They can be removed via Delsplits just like
  8510 Delsimps. Lower-case versions are also available.
  8511 
  8512 * HOL/Simplifier: The rule split_if is now part of the default
  8513 simpset. This means that the simplifier will eliminate all occurrences
  8514 of if-then-else in the conclusion of a goal. To prevent this, you can
  8515 either remove split_if completely from the default simpset by
  8516 `Delsplits [split_if]' or remove it in a specific call of the
  8517 simplifier using `... delsplits [split_if]'.  You can also add/delete
  8518 other case splitting rules to/from the default simpset: every datatype
  8519 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  8520 t is the name of the datatype).
  8521 
  8522 * Classical reasoner / Simplifier combination: new force_tac (and
  8523 derivatives Force_tac, force) combines rewriting and classical
  8524 reasoning (and whatever other tools) similarly to auto_tac, but is
  8525 aimed to solve the given subgoal completely.
  8526 
  8527 
  8528 *** General ***
  8529 
  8530 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  8531 and `goalw': the theory is no longer needed as an explicit argument -
  8532 the current theory context is used; assumptions are no longer returned
  8533 at the ML-level unless one of them starts with ==> or !!; it is
  8534 recommended to convert to these new commands using isatool fixgoal
  8535 (backup your sources first!);
  8536 
  8537 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  8538 the current theory context, and 'theory' to lookup stored theories;
  8539 
  8540 * new theory section 'locale' for declaring constants, assumptions and
  8541 definitions that have local scope;
  8542 
  8543 * new theory section 'nonterminals' for purely syntactic types;
  8544 
  8545 * new theory section 'setup' for generic ML setup functions
  8546 (e.g. package initialization);
  8547 
  8548 * the distribution now includes Isabelle icons: see
  8549 lib/logo/isabelle-{small,tiny}.xpm;
  8550 
  8551 * isatool install - install binaries with absolute references to
  8552 ISABELLE_HOME/bin;
  8553 
  8554 * isatool logo -- create instances of the Isabelle logo (as EPS);
  8555 
  8556 * print mode 'emacs' reserved for Isamode;
  8557 
  8558 * support multiple print (ast) translations per constant name;
  8559 
  8560 * theorems involving oracles are now printed with a suffixed [!];
  8561 
  8562 
  8563 *** HOL ***
  8564 
  8565 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  8566 
  8567 * HOL/inductive package reorganized and improved: now supports mutual
  8568 definitions such as
  8569 
  8570   inductive EVEN ODD
  8571     intrs
  8572       null "0 : EVEN"
  8573       oddI "n : EVEN ==> Suc n : ODD"
  8574       evenI "n : ODD ==> Suc n : EVEN"
  8575 
  8576 new theorem list "elims" contains an elimination rule for each of the
  8577 recursive sets; inductive definitions now handle disjunctive premises
  8578 correctly (also ZF);
  8579 
  8580 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  8581 "mutual_induct" no longer exists - the induction rule is always
  8582 contained in "induct";
  8583 
  8584 
  8585 * HOL/datatype package re-implemented and greatly improved: now
  8586 supports mutually recursive datatypes such as
  8587 
  8588   datatype
  8589     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  8590             | SUM ('a aexp) ('a aexp)
  8591             | DIFF ('a aexp) ('a aexp)
  8592             | NUM 'a
  8593   and
  8594     'a bexp = LESS ('a aexp) ('a aexp)
  8595             | AND ('a bexp) ('a bexp)
  8596             | OR ('a bexp) ('a bexp)
  8597 
  8598 as well as indirectly recursive datatypes such as
  8599 
  8600   datatype
  8601     ('a, 'b) term = Var 'a
  8602                   | App 'b ((('a, 'b) term) list)
  8603 
  8604 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  8605 induction on mutually / indirectly recursive datatypes.
  8606 
  8607 Primrec equations are now stored in theory and can be accessed via
  8608 <function_name>.simps.
  8609 
  8610 INCOMPATIBILITIES:
  8611 
  8612   - Theories using datatypes must now have theory Datatype as an
  8613     ancestor.
  8614   - The specific <typename>.induct_tac no longer exists - use the
  8615     generic induct_tac instead.
  8616   - natE has been renamed to nat.exhaust - use exhaust_tac
  8617     instead of res_inst_tac ... natE. Note that the variable
  8618     names in nat.exhaust differ from the names in natE, this
  8619     may cause some "fragile" proofs to fail.
  8620   - The theorems split_<typename>_case and split_<typename>_case_asm
  8621     have been renamed to <typename>.split and <typename>.split_asm.
  8622   - Since default sorts of type variables are now handled correctly,
  8623     some datatype definitions may have to be annotated with explicit
  8624     sort constraints.
  8625   - Primrec definitions no longer require function name and type
  8626     of recursive argument.
  8627 
  8628 Consider using isatool fixdatatype to adapt your theories and proof
  8629 scripts to the new package (backup your sources first!).
  8630 
  8631 
  8632 * HOL/record package: considerably improved implementation; now
  8633 includes concrete syntax for record types, terms, updates; theorems
  8634 for surjective pairing and splitting !!-bound record variables; proof
  8635 support is as follows:
  8636 
  8637   1) standard conversions (selectors or updates applied to record
  8638 constructor terms) are part of the standard simpset;
  8639 
  8640   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  8641 made part of standard simpset and claset via addIffs;
  8642 
  8643   3) a tactic for record field splitting (record_split_tac) is part of
  8644 the standard claset (addSWrapper);
  8645 
  8646 To get a better idea about these rules you may retrieve them via
  8647 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  8648 the name of your record type.
  8649 
  8650 The split tactic 3) conceptually simplifies by the following rule:
  8651 
  8652   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  8653 
  8654 Thus any record variable that is bound by meta-all will automatically
  8655 blow up into some record constructor term, consequently the
  8656 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  8657 solve record problems automatically.
  8658 
  8659 
  8660 * reorganized the main HOL image: HOL/Integ and String loaded by
  8661 default; theory Main includes everything;
  8662 
  8663 * automatic simplification of integer sums and comparisons, using cancellation;
  8664 
  8665 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  8666 
  8667 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  8668 
  8669 * many new identities for unions, intersections, set difference, etc.;
  8670 
  8671 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  8672 called split_if, split_split, split_sum_case and split_nat_case (to go
  8673 with add/delsplits);
  8674 
  8675 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  8676 (?x::unit) = (); this is made part of the default simpset, which COULD
  8677 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  8678 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  8679 unit_abs_eta_conv is added in order to counter the effect of
  8680 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  8681 %u.f();
  8682 
  8683 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  8684 makes more sense);
  8685 
  8686 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8687   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8688   disjointness reasoning but breaking a few old proofs.
  8689 
  8690 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  8691 to 'converse' from 'inverse' (for compatibility with ZF and some
  8692 literature);
  8693 
  8694 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  8695 the well-founded relation;
  8696 
  8697 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8698     Compl A.  The "Compl" syntax remains available as input syntax for this
  8699     release ONLY.
  8700 
  8701 * HOL/Update: new theory of function updates:
  8702     f(a:=b) == %x. if x=a then b else f x
  8703 may also be iterated as in f(a:=b,c:=d,...);
  8704 
  8705 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8706 
  8707 * HOL/List:
  8708   - new function list_update written xs[i:=v] that updates the i-th
  8709     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8710   - new function `upt' written [i..j(] which generates the list
  8711     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8712     bound write [i..j], which is a shorthand for [i..j+1(].
  8713   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8714 
  8715 * HOL/Arith:
  8716   - removed 'pred' (predecessor) function;
  8717   - generalized some theorems about n-1;
  8718   - many new laws about "div" and "mod";
  8719   - new laws about greatest common divisors (see theory ex/Primes);
  8720 
  8721 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8722 instead of "inverse";
  8723 
  8724 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8725   of the multiset ordering;
  8726 
  8727 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8728   (not included by default);
  8729 
  8730 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8731 
  8732 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8733   programs, i.e. different program variables may have different types.
  8734 
  8735 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8736   [previously, this check worked only if the rewrite rule was unconditional]
  8737   Now rew can involve either definitions or equalities (either == or =).
  8738 
  8739 
  8740 *** ZF ***
  8741 
  8742 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8743   only the theorems proved on ZF.ML;
  8744 
  8745 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8746   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8747   disjointness reasoning but breaking a few old proofs.
  8748 
  8749 * ZF/Update: new theory of function updates
  8750     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8751   may also be iterated as in f(a:=b,c:=d,...);
  8752 
  8753 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8754 
  8755 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8756   [previously, this check worked only if the rewrite rule was unconditional]
  8757   Now rew can involve either definitions or equalities (either == or =).
  8758 
  8759 * case_tac provided for compatibility with HOL
  8760     (like the old excluded_middle_tac, but with subgoals swapped)
  8761 
  8762 
  8763 *** Internal programming interfaces ***
  8764 
  8765 * Pure: several new basic modules made available for general use, see
  8766 also src/Pure/README;
  8767 
  8768 * improved the theory data mechanism to support encapsulation (data
  8769 kind name replaced by private Object.kind, acting as authorization
  8770 key); new type-safe user interface via functor TheoryDataFun; generic
  8771 print_data function becomes basically useless;
  8772 
  8773 * removed global_names compatibility flag -- all theory declarations
  8774 are qualified by default;
  8775 
  8776 * module Pure/Syntax now offers quote / antiquote translation
  8777 functions (useful for Hoare logic etc. with implicit dependencies);
  8778 see HOL/ex/Antiquote for an example use;
  8779 
  8780 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8781 cterm -> thm;
  8782 
  8783 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8784 subgoal;
  8785 
  8786 * Display.print_goals function moved to Locale.print_goals;
  8787 
  8788 * standard print function for goals supports current_goals_markers
  8789 variable for marking begin of proof, end of proof, start of goal; the
  8790 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8791 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8792 for example;
  8793 
  8794 
  8795 
  8796 New in Isabelle98 (January 1998)
  8797 --------------------------------
  8798 
  8799 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8800 
  8801 * changed lexical syntax of terms / types: dots made part of long
  8802 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8803 
  8804 * simpset (and claset) reference variable replaced by functions
  8805 simpset / simpset_ref;
  8806 
  8807 * no longer supports theory aliases (via merge) and non-trivial
  8808 implicit merge of thms' signatures;
  8809 
  8810 * most internal names of constants changed due to qualified names;
  8811 
  8812 * changed Pure/Sequence interface (see Pure/seq.ML);
  8813 
  8814 
  8815 *** General Changes ***
  8816 
  8817 * hierachically structured name spaces (for consts, types, axms, thms
  8818 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8819 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8820 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8821 long_names for fully qualified output names; NOTE: ML programs
  8822 (special tactics, packages etc.) referring to internal names may have
  8823 to be adapted to cope with fully qualified names; in case of severe
  8824 backward campatibility problems try setting 'global_names' at compile
  8825 time to have enrything declared within a flat name space; one may also
  8826 fine tune name declarations in theories via the 'global' and 'local'
  8827 section;
  8828 
  8829 * reimplemented the implicit simpset and claset using the new anytype
  8830 data filed in signatures; references simpset:simpset ref etc. are
  8831 replaced by functions simpset:unit->simpset and
  8832 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8833 to patch your ML files accordingly;
  8834 
  8835 * HTML output now includes theory graph data for display with Java
  8836 applet or isatool browser; data generated automatically via isatool
  8837 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8838 
  8839 * defs may now be conditional; improved rewrite_goals_tac to handle
  8840 conditional equations;
  8841 
  8842 * defs now admits additional type arguments, using TYPE('a) syntax;
  8843 
  8844 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8845 creates a new theory node; implicit merge of thms' signatures is
  8846 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8847 transfer:theory->thm->thm in (rare) cases;
  8848 
  8849 * improved handling of draft signatures / theories; draft thms (and
  8850 ctyps, cterms) are automatically promoted to real ones;
  8851 
  8852 * slightly changed interfaces for oracles: admit many per theory, named
  8853 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8854 
  8855 * print_goals: optional output of const types (set show_consts and
  8856 show_types);
  8857 
  8858 * improved output of warnings (###) and errors (***);
  8859 
  8860 * subgoal_tac displays a warning if the new subgoal has type variables;
  8861 
  8862 * removed old README and Makefiles;
  8863 
  8864 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8865 
  8866 * removed obsolete init_pps and init_database;
  8867 
  8868 * deleted the obsolete tactical STATE, which was declared by
  8869     fun STATE tacfun st = tacfun st st;
  8870 
  8871 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8872 (which abbreviates $HOME);
  8873 
  8874 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8875 use isatool fixseq to adapt your ML programs (this works for fully
  8876 qualified references to the Sequence structure only!);
  8877 
  8878 * use_thy no longer requires writable current directory; it always
  8879 reloads .ML *and* .thy file, if either one is out of date;
  8880 
  8881 
  8882 *** Classical Reasoner ***
  8883 
  8884 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8885 tactics that use classical reasoning to simplify a subgoal without
  8886 splitting it into several subgoals;
  8887 
  8888 * Safe_tac: like safe_tac but uses the default claset;
  8889 
  8890 
  8891 *** Simplifier ***
  8892 
  8893 * added simplification meta rules:
  8894     (asm_)(full_)simplify: simpset -> thm -> thm;
  8895 
  8896 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8897 logics (again);
  8898 
  8899 * added prems argument to simplification procedures;
  8900 
  8901 * HOL, FOL, ZF: added infix function `addsplits':
  8902   instead of `<simpset> setloop (split_tac <thms>)'
  8903   you can simply write `<simpset> addsplits <thms>'
  8904 
  8905 
  8906 *** Syntax ***
  8907 
  8908 * TYPE('a) syntax for type reflection terms;
  8909 
  8910 * no longer handles consts with name "" -- declare as 'syntax' instead;
  8911 
  8912 * pretty printer: changed order of mixfix annotation preference (again!);
  8913 
  8914 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  8915 
  8916 
  8917 *** HOL ***
  8918 
  8919 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8920   with `addloop' of the simplifier to faciliate case splitting in premises.
  8921 
  8922 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  8923 
  8924 * HOL/Auth: new protocol proofs including some for the Internet
  8925   protocol TLS;
  8926 
  8927 * HOL/Map: new theory of `maps' a la VDM;
  8928 
  8929 * HOL/simplifier: simplification procedures nat_cancel_sums for
  8930 cancelling out common nat summands from =, <, <= (in)equalities, or
  8931 differences; simplification procedures nat_cancel_factor for
  8932 cancelling common factor from =, <, <= (in)equalities over natural
  8933 sums; nat_cancel contains both kinds of procedures, it is installed by
  8934 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  8935 
  8936 * HOL/simplifier: terms of the form
  8937   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  8938   are rewritten to
  8939   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  8940   and those of the form
  8941   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  8942   are rewritten to
  8943   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  8944 
  8945 * HOL/datatype
  8946   Each datatype `t' now comes with a theorem `split_t_case' of the form
  8947 
  8948   P(t_case f1 ... fn x) =
  8949      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  8950         ...
  8951        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  8952      )
  8953 
  8954   and a theorem `split_t_case_asm' of the form
  8955 
  8956   P(t_case f1 ... fn x) =
  8957     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  8958         ...
  8959        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  8960      )
  8961   which can be added to a simpset via `addsplits'. The existing theorems
  8962   expand_list_case and expand_option_case have been renamed to
  8963   split_list_case and split_option_case.
  8964 
  8965 * HOL/Arithmetic:
  8966   - `pred n' is automatically converted to `n-1'.
  8967     Users are strongly encouraged not to use `pred' any longer,
  8968     because it will disappear altogether at some point.
  8969   - Users are strongly encouraged to write "0 < n" rather than
  8970     "n ~= 0". Theorems and proof tools have been modified towards this
  8971     `standard'.
  8972 
  8973 * HOL/Lists:
  8974   the function "set_of_list" has been renamed "set" (and its theorems too);
  8975   the function "nth" now takes its arguments in the reverse order and
  8976   has acquired the infix notation "!" as in "xs!n".
  8977 
  8978 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  8979 
  8980 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  8981   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  8982 
  8983 * HOL/record: extensible records with schematic structural subtyping
  8984 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  8985 still lacks various theorems and concrete record syntax;
  8986 
  8987 
  8988 *** HOLCF ***
  8989 
  8990 * removed "axioms" and "generated by" sections;
  8991 
  8992 * replaced "ops" section by extended "consts" section, which is capable of
  8993   handling the continuous function space "->" directly;
  8994 
  8995 * domain package:
  8996   . proves theorems immediately and stores them in the theory,
  8997   . creates hierachical name space,
  8998   . now uses normal mixfix annotations (instead of cinfix...),
  8999   . minor changes to some names and values (for consistency),
  9000   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  9001   . separator between mutual domain defs: changed "," to "and",
  9002   . improved handling of sort constraints;  now they have to
  9003     appear on the left-hand side of the equations only;
  9004 
  9005 * fixed LAM <x,y,zs>.b syntax;
  9006 
  9007 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  9008 adm (%x. P (t x)), where P is chainfinite and t continuous;
  9009 
  9010 
  9011 *** FOL and ZF ***
  9012 
  9013 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  9014   with `addloop' of the simplifier to faciliate case splitting in premises.
  9015 
  9016 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  9017 in HOL, they strip ALL and --> from proved theorems;
  9018 
  9019 
  9020 
  9021 New in Isabelle94-8 (May 1997)
  9022 ------------------------------
  9023 
  9024 *** General Changes ***
  9025 
  9026 * new utilities to build / run / maintain Isabelle etc. (in parts
  9027 still somewhat experimental); old Makefiles etc. still functional;
  9028 
  9029 * new 'Isabelle System Manual';
  9030 
  9031 * INSTALL text, together with ./configure and ./build scripts;
  9032 
  9033 * reimplemented type inference for greater efficiency, better error
  9034 messages and clean internal interface;
  9035 
  9036 * prlim command for dealing with lots of subgoals (an easier way of
  9037 setting goals_limit);
  9038 
  9039 
  9040 *** Syntax ***
  9041 
  9042 * supports alternative (named) syntax tables (parser and pretty
  9043 printer); internal interface is provided by add_modesyntax(_i);
  9044 
  9045 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  9046 be used in conjunction with the Isabelle symbol font; uses the
  9047 "symbols" syntax table;
  9048 
  9049 * added token_translation interface (may translate name tokens in
  9050 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  9051 the current print_mode); IMPORTANT: user print translation functions
  9052 are responsible for marking newly introduced bounds
  9053 (Syntax.mark_boundT);
  9054 
  9055 * token translations for modes "xterm" and "xterm_color" that display
  9056 names in bold, underline etc. or colors (which requires a color
  9057 version of xterm);
  9058 
  9059 * infixes may now be declared with names independent of their syntax;
  9060 
  9061 * added typed_print_translation (like print_translation, but may
  9062 access type of constant);
  9063 
  9064 
  9065 *** Classical Reasoner ***
  9066 
  9067 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  9068 some limitations.  Blast_tac...
  9069   + ignores addss, addbefore, addafter; this restriction is intrinsic
  9070   + ignores elimination rules that don't have the correct format
  9071         (the conclusion MUST be a formula variable)
  9072   + ignores types, which can make HOL proofs fail
  9073   + rules must not require higher-order unification, e.g. apply_type in ZF
  9074     [message "Function Var's argument not a bound variable" relates to this]
  9075   + its proof strategy is more general but can actually be slower
  9076 
  9077 * substitution with equality assumptions no longer permutes other
  9078 assumptions;
  9079 
  9080 * minor changes in semantics of addafter (now called addaltern); renamed
  9081 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  9082 (and access functions for it);
  9083 
  9084 * improved combination of classical reasoner and simplifier:
  9085   + functions for handling clasimpsets
  9086   + improvement of addss: now the simplifier is called _after_ the
  9087     safe steps.
  9088   + safe variant of addss called addSss: uses safe simplifications
  9089     _during_ the safe steps. It is more complete as it allows multiple
  9090     instantiations of unknowns (e.g. with slow_tac).
  9091 
  9092 *** Simplifier ***
  9093 
  9094 * added interface for simplification procedures (functions that
  9095 produce *proven* rewrite rules on the fly, depending on current
  9096 redex);
  9097 
  9098 * ordering on terms as parameter (used for ordered rewriting);
  9099 
  9100 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  9101 
  9102 * the solver is now split into a safe and an unsafe part.
  9103 This should be invisible for the normal user, except that the
  9104 functions setsolver and addsolver have been renamed to setSolver and
  9105 addSolver; added safe_asm_full_simp_tac;
  9106 
  9107 
  9108 *** HOL ***
  9109 
  9110 * a generic induction tactic `induct_tac' which works for all datatypes and
  9111 also for type `nat';
  9112 
  9113 * a generic case distinction tactic `exhaust_tac' which works for all
  9114 datatypes and also for type `nat';
  9115 
  9116 * each datatype comes with a function `size';
  9117 
  9118 * patterns in case expressions allow tuple patterns as arguments to
  9119 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  9120 
  9121 * primrec now also works with type nat;
  9122 
  9123 * recdef: a new declaration form, allows general recursive functions to be
  9124 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  9125 
  9126 * the constant for negation has been renamed from "not" to "Not" to
  9127 harmonize with FOL, ZF, LK, etc.;
  9128 
  9129 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  9130 infinite lists;
  9131 
  9132 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  9133 
  9134 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  9135 problems in commutative rings, using axiomatic type classes for + and *;
  9136 
  9137 * more examples in HOL/MiniML and HOL/Auth;
  9138 
  9139 * more default rewrite rules for quantifiers, union/intersection;
  9140 
  9141 * a new constant `arbitrary == @x.False';
  9142 
  9143 * HOLCF/IOA replaces old HOL/IOA;
  9144 
  9145 * HOLCF changes: derived all rules and arities
  9146   + axiomatic type classes instead of classes
  9147   + typedef instead of faking type definitions
  9148   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  9149   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  9150   + eliminated the types void, one, tr
  9151   + use unit lift and bool lift (with translations) instead of one and tr
  9152   + eliminated blift from Lift3.thy (use Def instead of blift)
  9153   all eliminated rules are derived as theorems --> no visible changes ;
  9154 
  9155 
  9156 *** ZF ***
  9157 
  9158 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  9159 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  9160 as ZF_cs addSIs [equalityI];
  9161 
  9162 
  9163 
  9164 New in Isabelle94-7 (November 96)
  9165 ---------------------------------
  9166 
  9167 * allowing negative levels (as offsets) in prlev and choplev;
  9168 
  9169 * super-linear speedup for large simplifications;
  9170 
  9171 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  9172 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  9173 FAIL); can suppress it using the command Delsimps (ex_simps @
  9174 all_simps); De Morgan laws are also now included, by default;
  9175 
  9176 * improved printing of ==>  :  ~:
  9177 
  9178 * new object-logic "Sequents" adds linear logic, while replacing LK
  9179 and Modal (thanks to Sara Kalvala);
  9180 
  9181 * HOL/Auth: correctness proofs for authentication protocols;
  9182 
  9183 * HOL: new auto_tac combines rewriting and classical reasoning (many
  9184 examples on HOL/Auth);
  9185 
  9186 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  9187 the rewriter and classical reasoner simultaneously;
  9188 
  9189 * function uresult no longer returns theorems in "standard" format;
  9190 regain previous version by: val uresult = standard o uresult;
  9191 
  9192 
  9193 
  9194 New in Isabelle94-6
  9195 -------------------
  9196 
  9197 * oracles -- these establish an interface between Isabelle and trusted
  9198 external reasoners, which may deliver results as theorems;
  9199 
  9200 * proof objects (in particular record all uses of oracles);
  9201 
  9202 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  9203 
  9204 * "constdefs" section in theory files;
  9205 
  9206 * "primrec" section (HOL) no longer requires names;
  9207 
  9208 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  9209 
  9210 
  9211 
  9212 New in Isabelle94-5
  9213 -------------------
  9214 
  9215 * reduced space requirements;
  9216 
  9217 * automatic HTML generation from theories;
  9218 
  9219 * theory files no longer require "..." (quotes) around most types;
  9220 
  9221 * new examples, including two proofs of the Church-Rosser theorem;
  9222 
  9223 * non-curried (1994) version of HOL is no longer distributed;
  9224 
  9225 
  9226 
  9227 New in Isabelle94-4
  9228 -------------------
  9229 
  9230 * greatly reduced space requirements;
  9231 
  9232 * theory files (.thy) no longer require \...\ escapes at line breaks;
  9233 
  9234 * searchable theorem database (see the section "Retrieving theorems" on
  9235 page 8 of the Reference Manual);
  9236 
  9237 * new examples, including Grabczewski's monumental case study of the
  9238 Axiom of Choice;
  9239 
  9240 * The previous version of HOL renamed to Old_HOL;
  9241 
  9242 * The new version of HOL (previously called CHOL) uses a curried syntax
  9243 for functions.  Application looks like f a b instead of f(a,b);
  9244 
  9245 * Mutually recursive inductive definitions finally work in HOL;
  9246 
  9247 * In ZF, pattern-matching on tuples is now available in all abstractions and
  9248 translates to the operator "split";
  9249 
  9250 
  9251 
  9252 New in Isabelle94-3
  9253 -------------------
  9254 
  9255 * new infix operator, addss, allowing the classical reasoner to
  9256 perform simplification at each step of its search.  Example:
  9257         fast_tac (cs addss ss)
  9258 
  9259 * a new logic, CHOL, the same as HOL, but with a curried syntax
  9260 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  9261 look like (a,b) instead of <a,b>;
  9262 
  9263 * PLEASE NOTE: CHOL will eventually replace HOL!
  9264 
  9265 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  9266 It translates to the operator "split".  A new theory of integers is available;
  9267 
  9268 * In ZF, integer numerals now denote two's-complement binary integers.
  9269 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  9270 
  9271 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  9272 of the Axiom of Choice;
  9273 
  9274 
  9275 
  9276 New in Isabelle94-2
  9277 -------------------
  9278 
  9279 * Significantly faster resolution;
  9280 
  9281 * the different sections in a .thy file can now be mixed and repeated
  9282 freely;
  9283 
  9284 * Database of theorems for FOL, HOL and ZF.  New
  9285 commands including qed, qed_goal and bind_thm store theorems in the database.
  9286 
  9287 * Simple database queries: return a named theorem (get_thm) or all theorems of
  9288 a given theory (thms_of), or find out what theory a theorem was proved in
  9289 (theory_of_thm);
  9290 
  9291 * Bugs fixed in the inductive definition and datatype packages;
  9292 
  9293 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  9294 and HOL_dup_cs obsolete;
  9295 
  9296 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  9297 have been removed;
  9298 
  9299 * Simpler definition of function space in ZF;
  9300 
  9301 * new results about cardinal and ordinal arithmetic in ZF;
  9302 
  9303 * 'subtype' facility in HOL for introducing new types as subsets of existing
  9304 types;
  9305 
  9306 :mode=text:wrap=hard:maxLineLen=72: