NEWS
author wenzelm
Sat, 17 Mar 2012 23:55:03 +0100
changeset 47872 a0e370d3d149
parent 47865 eeea81b86b70
child 47952 69276374c0a1
permissions -rw-r--r--
proper naming of simprocs according to actual target context;
afford pervasive declaration which makes results available with qualified name from outside;
     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 
    15 * Updated and extended reference manuals ("isar-ref" and
    16 "implementation"); reduced remaining material in old "ref" manual.
    17 
    18 * Rule attributes in local theory declarations (e.g. locale or class)
    19 are now statically evaluated: the resulting theorem is stored instead
    20 of the original expression.  INCOMPATIBILITY in rare situations, where
    21 the historic accident of dynamic re-evaluation in interpretations
    22 etc. was exploited.
    23 
    24 * Commands 'lemmas' and 'theorems' allow local variables using 'for'
    25 declaration, and results are standardized before being stored.  Thus
    26 old-style "standard" after instantiation or composition of facts
    27 becomes obsolete.  Minor INCOMPATIBILITY, due to potential change of
    28 indices of schematic variables.
    29 
    30 * Renamed some inner syntax categories:
    31 
    32     num ~> num_token
    33     xnum ~> xnum_token
    34     xstr ~> str_token
    35 
    36 Minor INCOMPATIBILITY.  Note that in practice "num_const" or
    37 "num_position" etc. are mainly used instead (which also include
    38 position information via constraints).
    39 
    40 * Simplified configuration options for syntax ambiguity: see
    41 "syntax_ambiguity_warning" and "syntax_ambiguity_limit" in isar-ref
    42 manual.  Minor INCOMPATIBILITY.
    43 
    44 * Forward declaration of outer syntax keywords within the theory
    45 header -- minor INCOMPATIBILITY for user-defined commands.  Allow new
    46 commands to be used in the same theory where defined.
    47 
    48 
    49 *** Pure ***
    50 
    51 * Command 'definition' no longer exports the foundational "raw_def"
    52 into the user context.  Minor INCOMPATIBILITY, may use the regular
    53 "def" result with attribute "abs_def" to imitate the old version.
    54 
    55 * Attribute "abs_def" turns an equation of the form "f x y == t" into
    56 "f == %x y. t", which ensures that "simp" or "unfold" steps always
    57 expand it.  This also works for object-logic equality.  (Formerly
    58 undocumented feature.)
    59 
    60 * Discontinued old "prems" fact, which used to refer to the accidental
    61 collection of foundational premises in the context (marked as legacy
    62 since Isabelle2011).
    63 
    64 * Obsolete command 'types' has been discontinued.  Use 'type_synonym'
    65 instead.  INCOMPATIBILITY.
    66 
    67 * Ancient code generator for SML and its commands 'code_module',
    68 'code_library', 'consts_code', 'types_code' have been discontinued.
    69 Use commands of the generic code generator instead.  INCOMPATIBILITY.
    70 
    71 * Redundant attribute 'code_inline' has been discontinued. Use
    72 'code_unfold' instead.  INCOMPATIBILITY.
    73 
    74 * Dropped attribute 'code_unfold_post' in favor of the its dual
    75 'code_abbrev', which yields a common pattern in definitions like
    76 
    77   definition [code_abbrev]: "f = t"
    78 
    79 INCOMPATIBILITY.
    80 
    81 * Sort constraints are now propagated in simultaneous statements, just
    82 like type constraints.  INCOMPATIBILITY in rare situations, where
    83 distinct sorts used to be assigned accidentally.  For example:
    84 
    85   lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"
    86 
    87   lemma "P (x::'a)" and "Q (y::'a::bar)"
    88     -- "now uniform 'a::bar instead of default sort for first occurence (!)"
    89 
    90 
    91 *** HOL ***
    92 
    93 * Type 'a set is now a proper type constructor (just as before
    94 Isabelle2008).  Definitions mem_def and Collect_def have disappeared.
    95 Non-trivial INCOMPATIBILITY.  For developments keeping predicates and
    96 sets separate, it is often sufficient to rephrase sets S accidentally
    97 used as predicates by "%x. x : S" and predicates P accidentally used
    98 as sets by "{x. P x}".  Corresponding proofs in a first step should be
    99 pruned from any tinkering with former theorems mem_def and
   100 Collect_def as far as possible.
   101 For developments which deliberately mixed predicates and
   102 sets, a planning step is necessary to determine what should become a
   103 predicate and what a set.  It can be helpful to carry out that step in
   104 Isabelle2011-1 before jumping right into the current release.
   105 
   106 * Code generation by default implements sets as container type rather
   107 than predicates.  INCOMPATIBILITY.
   108 
   109 * New type synonym 'a rel = ('a * 'a) set
   110 
   111 * More default pred/set conversions on a couple of relation operations
   112 and predicates.  Consolidation of some relation theorems:
   113 
   114   converse_def ~> converse_unfold
   115   rel_comp_def ~> rel_comp_unfold
   116   symp_def ~> (dropped, use symp_def and sym_def instead)
   117   transp_def ~> transp_trans
   118   Domain_def ~> Domain_unfold
   119   Range_def ~> Domain_converse [symmetric]
   120 
   121 Generalized theorems INF_INT_eq, INF_INT_eq2, SUP_UN_eq, SUP_UN_eq2.
   122 
   123 INCOMPATIBILITY.
   124 
   125 * Consolidated various theorem names relating to Finite_Set.fold
   126 combinator:
   127 
   128   inf_INFI_fold_inf ~> inf_INF_fold_inf
   129   sup_SUPR_fold_sup ~> sup_SUP_fold_sup
   130   INFI_fold_inf ~> INF_fold_inf
   131   SUPR_fold_sup ~> SUP_fold_sup
   132   union_set ~> union_set_fold
   133   minus_set ~> minus_set_fold
   134 
   135 INCOMPATIBILITY.
   136 
   137 * Consolidated theorem names concerning fold combinators:
   138 
   139   INFI_set_fold ~> INF_set_fold
   140   SUPR_set_fold ~> SUP_set_fold
   141   INF_code ~> INF_set_foldr
   142   SUP_code ~> SUP_set_foldr
   143   foldr.simps ~> foldr_Nil foldr_Cons (in point-free formulation)
   144   foldl.simps ~> foldl_Nil foldl_Cons
   145   foldr_fold_rev ~> foldr_def
   146   foldl_fold ~> foldl_def
   147 
   148 INCOMPATIBILITY.
   149 
   150 * Dropped rarely useful theorems concerning fold combinators:
   151 foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
   152 rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
   153 concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
   154 foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
   155 listsum_conv_fold, listsum_foldl, sort_foldl_insort.  INCOMPATIBILITY.
   156 Prefer "List.fold" with canonical argument order, or boil down
   157 "List.foldr" and "List.foldl" to "List.fold" by unfolding "foldr_def"
   158 and "foldl_def".  For the common phrases "%xs. List.foldr plus xs 0"
   159 and "List.foldl plus 0", prefer "List.listsum".
   160 
   161 * Congruence rules Option.map_cong and Option.bind_cong for recursion
   162 through option types.
   163 
   164 * Concrete syntax for case expressions includes constraints for source
   165 positions, and thus produces Prover IDE markup for its bindings.
   166 INCOMPATIBILITY for old-style syntax translations that augment the
   167 pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of
   168 one_case.
   169 
   170 * Discontinued configuration option "syntax_positions": atomic terms
   171 in parse trees are always annotated by position constraints.
   172 
   173 * Finite_Set.fold now qualified.  INCOMPATIBILITY.
   174 
   175 * Renamed some facts on canonical fold on lists, in order to avoid
   176 problems with interpretation involving corresponding facts on foldl
   177 with the same base names:
   178 
   179   fold_set_remdups ~> fold_set_fold_remdups
   180   fold_set ~> fold_set_fold
   181   fold1_set ~> fold1_set_fold
   182 
   183 INCOMPATIBILITY.
   184 
   185 * Renamed facts about the power operation on relations, i.e., relpow
   186   to match the constant's name:
   187   
   188   rel_pow_1 ~> relpow_1
   189   rel_pow_0_I ~> relpow_0_I
   190   rel_pow_Suc_I ~> relpow_Suc_I
   191   rel_pow_Suc_I2 ~> relpow_Suc_I2
   192   rel_pow_0_E ~> relpow_0_E
   193   rel_pow_Suc_E ~> relpow_Suc_E
   194   rel_pow_E ~> relpow_E
   195   rel_pow_Suc_D2 ~> relpow_Suc_D2
   196   rel_pow_Suc_E2 ~> relpow_Suc_E2 
   197   rel_pow_Suc_D2' ~> relpow_Suc_D2'
   198   rel_pow_E2 ~> relpow_E2
   199   rel_pow_add ~> relpow_add
   200   rel_pow_commute ~> relpow
   201   rel_pow_empty ~> relpow_empty:
   202   rtrancl_imp_UN_rel_pow ~> rtrancl_imp_UN_relpow
   203   rel_pow_imp_rtrancl ~> relpow_imp_rtrancl
   204   rtrancl_is_UN_rel_pow ~> rtrancl_is_UN_relpow
   205   rtrancl_imp_rel_pow ~> rtrancl_imp_relpow
   206   rel_pow_fun_conv ~> relpow_fun_conv
   207   rel_pow_finite_bounded1 ~> relpow_finite_bounded1
   208   rel_pow_finite_bounded ~> relpow_finite_bounded
   209   rtrancl_finite_eq_rel_pow ~> rtrancl_finite_eq_relpow
   210   trancl_finite_eq_rel_pow ~> trancl_finite_eq_relpow
   211   single_valued_rel_pow ~> single_valued_relpow
   212  
   213 INCOMPATIBILITY.
   214 
   215 * New theory HOL/Library/DAList provides an abstract type for association
   216   lists with distinct keys.
   217 
   218 * 'datatype' specifications allow explicit sort constraints.
   219 
   220 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
   221 use theory HOL/Library/Nat_Bijection instead.
   222 
   223 * Session HOL-Word: Discontinued many redundant theorems specific to
   224 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
   225 instead.
   226 
   227   word_sub_alt ~> word_sub_wi
   228   word_add_alt ~> word_add_def
   229   word_mult_alt ~> word_mult_def
   230   word_minus_alt ~> word_minus_def
   231   word_0_alt ~> word_0_wi
   232   word_1_alt ~> word_1_wi
   233   word_add_0 ~> add_0_left
   234   word_add_0_right ~> add_0_right
   235   word_mult_1 ~> mult_1_left
   236   word_mult_1_right ~> mult_1_right
   237   word_add_commute ~> add_commute
   238   word_add_assoc ~> add_assoc
   239   word_add_left_commute ~> add_left_commute
   240   word_mult_commute ~> mult_commute
   241   word_mult_assoc ~> mult_assoc
   242   word_mult_left_commute ~> mult_left_commute
   243   word_left_distrib ~> left_distrib
   244   word_right_distrib ~> right_distrib
   245   word_left_minus ~> left_minus
   246   word_diff_0_right ~> diff_0_right
   247   word_diff_self ~> diff_self
   248   word_sub_def ~> diff_minus
   249   word_diff_minus ~> diff_minus
   250   word_add_ac ~> add_ac
   251   word_mult_ac ~> mult_ac
   252   word_plus_ac0 ~> add_0_left add_0_right add_ac
   253   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
   254   word_order_trans ~> order_trans
   255   word_order_refl ~> order_refl
   256   word_order_antisym ~> order_antisym
   257   word_order_linear ~> linorder_linear
   258   lenw1_zero_neq_one ~> zero_neq_one
   259   word_number_of_eq ~> number_of_eq
   260   word_of_int_add_hom ~> wi_hom_add
   261   word_of_int_sub_hom ~> wi_hom_sub
   262   word_of_int_mult_hom ~> wi_hom_mult
   263   word_of_int_minus_hom ~> wi_hom_neg
   264   word_of_int_succ_hom ~> wi_hom_succ
   265   word_of_int_pred_hom ~> wi_hom_pred
   266   word_of_int_0_hom ~> word_0_wi
   267   word_of_int_1_hom ~> word_1_wi
   268 
   269 * Clarified attribute "mono_set": pure declaration without modifying
   270 the result of the fact expression.
   271 
   272 * "Transitive_Closure.ntrancl": bounded transitive closure on
   273 relations.
   274 
   275 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
   276 
   277 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
   278 
   279 * Theory Int: Discontinued many legacy theorems specific to type int.
   280 INCOMPATIBILITY, use the corresponding generic theorems instead.
   281 
   282   zminus_zminus ~> minus_minus
   283   zminus_0 ~> minus_zero
   284   zminus_zadd_distrib ~> minus_add_distrib
   285   zadd_commute ~> add_commute
   286   zadd_assoc ~> add_assoc
   287   zadd_left_commute ~> add_left_commute
   288   zadd_ac ~> add_ac
   289   zmult_ac ~> mult_ac
   290   zadd_0 ~> add_0_left
   291   zadd_0_right ~> add_0_right
   292   zadd_zminus_inverse2 ~> left_minus
   293   zmult_zminus ~> mult_minus_left
   294   zmult_commute ~> mult_commute
   295   zmult_assoc ~> mult_assoc
   296   zadd_zmult_distrib ~> left_distrib
   297   zadd_zmult_distrib2 ~> right_distrib
   298   zdiff_zmult_distrib ~> left_diff_distrib
   299   zdiff_zmult_distrib2 ~> right_diff_distrib
   300   zmult_1 ~> mult_1_left
   301   zmult_1_right ~> mult_1_right
   302   zle_refl ~> order_refl
   303   zle_trans ~> order_trans
   304   zle_antisym ~> order_antisym
   305   zle_linear ~> linorder_linear
   306   zless_linear ~> linorder_less_linear
   307   zadd_left_mono ~> add_left_mono
   308   zadd_strict_right_mono ~> add_strict_right_mono
   309   zadd_zless_mono ~> add_less_le_mono
   310   int_0_less_1 ~> zero_less_one
   311   int_0_neq_1 ~> zero_neq_one
   312   zless_le ~> less_le
   313   zpower_zadd_distrib ~> power_add
   314   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   315   zero_le_zpower_abs ~> zero_le_power_abs
   316 
   317 * Theory Deriv: Renamed
   318 
   319   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   320 
   321 * New "case_product" attribute to generate a case rule doing multiple
   322 case distinctions at the same time.  E.g.
   323 
   324   list.exhaust [case_product nat.exhaust]
   325 
   326 produces a rule which can be used to perform case distinction on both
   327 a list and a nat.
   328 
   329 * Improved code generation of multisets.
   330 
   331 * New diagnostic command find_unused_assms to find potentially superfluous
   332   assumptions in theorems using Quickcheck.
   333 
   334 * Quickcheck:
   335   - Quickcheck returns variable assignments as counterexamples, which
   336     allows to reveal the underspecification of functions under test.
   337     For example, refuting "hd xs = x", it presents the variable
   338     assignment xs = [] and x = a1 as a counterexample, assuming that
   339     any property is false whenever "hd []" occurs in it.
   340     These counterexample are marked as potentially spurious, as
   341     Quickcheck also returns "xs = []" as a counterexample to the
   342     obvious theorem "hd xs = hd xs".
   343     After finding a potentially spurious counterexample, Quickcheck
   344     continues searching for genuine ones.
   345     By default, Quickcheck shows potentially spurious and genuine
   346     counterexamples. The option "genuine_only" sets quickcheck to
   347     only show genuine counterexamples.
   348 
   349   - The command 'quickcheck_generator' creates random and exhaustive
   350     value generators for a given type and operations.
   351     It generates values by using the operations as if they were
   352     constructors of that type. 
   353 
   354   - Support for multisets.
   355 
   356   - Added "use_subtype" options.
   357  
   358 * Nitpick:
   359   - Fixed infinite loop caused by the 'peephole_optim' option and
   360     affecting 'rat' and 'real'.
   361 
   362 * Sledgehammer:
   363   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   364   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   365   - Renamed "sound" option to "strict".
   366 
   367 * Metis:
   368   - Added possibility to specify lambda translations scheme as a
   369     parenthesized argument (e.g., "by (metis (lifting) ...)").
   370 
   371 * Command 'try0':
   372   - Renamed from 'try_methods'. INCOMPATIBILITY.
   373 
   374 * New "eventually_elim" method as a generalized variant of the
   375   eventually_elim* rules. Supports structured proofs.
   376 
   377 
   378 *** FOL ***
   379 
   380 * New "case_product" attribute (see HOL).
   381 
   382 
   383 *** ML ***
   384 
   385 * Antiquotation @{keyword "name"} produces a parser for outer syntax
   386 from a minor keyword introduced via theory header declaration.
   387 
   388 * Antiquotation @{command_spec "name"} produces the
   389 Outer_Syntax.command_spec from a major keyword introduced via theory
   390 header declaration; it can be passed to Outer_Syntax.command etc.
   391 
   392 * Local_Theory.define no longer hard-wires default theorem name
   393 "foo_def", but retains the binding as given.  If that is Binding.empty
   394 / Attrib.empty_binding, the result is not registered as user-level
   395 fact.  The Local_Theory.define_internal variant allows to specify a
   396 non-empty name (used for the foundation in the background theory),
   397 while omitting the fact binding in the user-context.  Potential
   398 INCOMPATIBILITY for derived definitional packages: need to specify
   399 naming policy for primitive definitions more explicitly.
   400 
   401 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
   402 conformance with similar operations in structure Term and Logic.
   403 
   404 * Antiquotation @{attributes [...]} embeds attribute source
   405 representation into the ML text, which is particularly useful with
   406 declarations like Local_Theory.note.
   407 
   408 * Structure Proof_Context follows standard naming scheme.  Old
   409 ProofContext has been discontinued.  INCOMPATIBILITY.
   410 
   411 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   412 change of semantics: update is applied to auxiliary local theory
   413 context as well.
   414 
   415 * Modernized some old-style infix operations:
   416 
   417   addeqcongs    ~> Simplifier.add_eqcong
   418   deleqcongs    ~> Simplifier.del_eqcong
   419   addcongs      ~> Simplifier.add_cong
   420   delcongs      ~> Simplifier.del_cong
   421   setmksimps    ~> Simplifier.set_mksimps
   422   setmkcong     ~> Simplifier.set_mkcong
   423   setmksym      ~> Simplifier.set_mksym
   424   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   425   settermless   ~> Simplifier.set_termless
   426   setsubgoaler  ~> Simplifier.set_subgoaler
   427   addsplits     ~> Splitter.add_split
   428   delsplits     ~> Splitter.del_split
   429 
   430 
   431 
   432 New in Isabelle2011-1 (October 2011)
   433 ------------------------------------
   434 
   435 *** General ***
   436 
   437 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   438 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   439 
   440   - Management of multiple theory files directly from the editor
   441     buffer store -- bypassing the file-system (no requirement to save
   442     files for checking).
   443 
   444   - Markup of formal entities within the text buffer, with semantic
   445     highlighting, tooltips and hyperlinks to jump to defining source
   446     positions.
   447 
   448   - Improved text rendering, with sub/superscripts in the source
   449     buffer (including support for copy/paste wrt. output panel, HTML
   450     theory output and other non-Isabelle text boxes).
   451 
   452   - Refined scheduling of proof checking and printing of results,
   453     based on interactive editor view.  (Note: jEdit folding and
   454     narrowing allows to restrict buffer perspectives explicitly.)
   455 
   456   - Reduced CPU performance requirements, usable on machines with few
   457     cores.
   458 
   459   - Reduced memory requirements due to pruning of unused document
   460     versions (garbage collection).
   461 
   462 See also ~~/src/Tools/jEdit/README.html for further information,
   463 including some remaining limitations.
   464 
   465 * Theory loader: source files are exclusively located via the master
   466 directory of each theory node (where the .thy file itself resides).
   467 The global load path (such as src/HOL/Library) has been discontinued.
   468 Note that the path element ~~ may be used to reference theories in the
   469 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   470 INCOMPATIBILITY.
   471 
   472 * Theory loader: source files are identified by content via SHA1
   473 digests.  Discontinued former path/modtime identification and optional
   474 ISABELLE_FILE_IDENT plugin scripts.
   475 
   476 * Parallelization of nested Isar proofs is subject to
   477 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   478 usedir option -Q.
   479 
   480 * Name space: former unsynchronized references are now proper
   481 configuration options, with more conventional names:
   482 
   483   long_names   ~> names_long
   484   short_names  ~> names_short
   485   unique_names ~> names_unique
   486 
   487 Minor INCOMPATIBILITY, need to declare options in context like this:
   488 
   489   declare [[names_unique = false]]
   490 
   491 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   492 that the result needs to be unique, which means fact specifications
   493 may have to be refined after enriching a proof context.
   494 
   495 * Attribute "case_names" has been refined: the assumptions in each case
   496 can be named now by following the case name with [name1 name2 ...].
   497 
   498 * Isabelle/Isar reference manual has been updated and extended:
   499   - "Synopsis" provides a catalog of main Isar language concepts.
   500   - Formal references in syntax diagrams, via @{rail} antiquotation.
   501   - Updated material from classic "ref" manual, notably about
   502     "Classical Reasoner".
   503 
   504 
   505 *** HOL ***
   506 
   507 * Class bot and top require underlying partial order rather than
   508 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   509 
   510 * Class complete_lattice: generalized a couple of lemmas from sets;
   511 generalized theorems INF_cong and SUP_cong.  New type classes for
   512 complete boolean algebras and complete linear orders.  Lemmas
   513 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   514 class complete_linorder.
   515 
   516 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   517 Sup_fun_def, Inf_apply, Sup_apply.
   518 
   519 Removed redundant lemmas (the right hand side gives hints how to
   520 replace them for (metis ...), or (simp only: ...) proofs):
   521 
   522   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   523   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   524   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   525   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   526   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   527   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   528   Inter_def ~> INF_def, image_def
   529   Union_def ~> SUP_def, image_def
   530   INT_eq ~> INF_def, and image_def
   531   UN_eq ~> SUP_def, and image_def
   532   INF_subset ~> INF_superset_mono [OF _ order_refl]
   533 
   534 More consistent and comprehensive names:
   535 
   536   INTER_eq_Inter_image ~> INF_def
   537   UNION_eq_Union_image ~> SUP_def
   538   INFI_def ~> INF_def
   539   SUPR_def ~> SUP_def
   540   INF_leI ~> INF_lower
   541   INF_leI2 ~> INF_lower2
   542   le_INFI ~> INF_greatest
   543   le_SUPI ~> SUP_upper
   544   le_SUPI2 ~> SUP_upper2
   545   SUP_leI ~> SUP_least
   546   INFI_bool_eq ~> INF_bool_eq
   547   SUPR_bool_eq ~> SUP_bool_eq
   548   INFI_apply ~> INF_apply
   549   SUPR_apply ~> SUP_apply
   550   INTER_def ~> INTER_eq
   551   UNION_def ~> UNION_eq
   552 
   553 INCOMPATIBILITY.
   554 
   555 * Renamed theory Complete_Lattice to Complete_Lattices.
   556 INCOMPATIBILITY.
   557 
   558 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   559 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   560 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   561 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   562 
   563 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   564 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   565 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   566 INCOMPATIBILITY.
   567 
   568 * Added syntactic classes "inf" and "sup" for the respective
   569 constants.  INCOMPATIBILITY: Changes in the argument order of the
   570 (mostly internal) locale predicates for some derived classes.
   571 
   572 * Theorem collections ball_simps and bex_simps do not contain theorems
   573 referring to UNION any longer; these have been moved to collection
   574 UN_ball_bex_simps.  INCOMPATIBILITY.
   575 
   576 * Theory Archimedean_Field: floor now is defined as parameter of a
   577 separate type class floor_ceiling.
   578 
   579 * Theory Finite_Set: more coherent development of fold_set locales:
   580 
   581     locale fun_left_comm ~> locale comp_fun_commute
   582     locale fun_left_comm_idem ~> locale comp_fun_idem
   583 
   584 Both use point-free characterization; interpretation proofs may need
   585 adjustment.  INCOMPATIBILITY.
   586 
   587 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   588 accordance with standard mathematical terminology. INCOMPATIBILITY.
   589 
   590 * Theory Complex_Main: The locale interpretations for the
   591 bounded_linear and bounded_bilinear locales have been removed, in
   592 order to reduce the number of duplicate lemmas. Users must use the
   593 original names for distributivity theorems, potential INCOMPATIBILITY.
   594 
   595   divide.add ~> add_divide_distrib
   596   divide.diff ~> diff_divide_distrib
   597   divide.setsum ~> setsum_divide_distrib
   598   mult.add_right ~> right_distrib
   599   mult.diff_right ~> right_diff_distrib
   600   mult_right.setsum ~> setsum_right_distrib
   601   mult_left.diff ~> left_diff_distrib
   602 
   603 * Theory Complex_Main: Several redundant theorems have been removed or
   604 replaced by more general versions. INCOMPATIBILITY.
   605 
   606   real_diff_def ~> minus_real_def
   607   real_divide_def ~> divide_real_def
   608   real_less_def ~> less_le
   609   real_abs_def ~> abs_real_def
   610   real_sgn_def ~> sgn_real_def
   611   real_mult_commute ~> mult_commute
   612   real_mult_assoc ~> mult_assoc
   613   real_mult_1 ~> mult_1_left
   614   real_add_mult_distrib ~> left_distrib
   615   real_zero_not_eq_one ~> zero_neq_one
   616   real_mult_inverse_left ~> left_inverse
   617   INVERSE_ZERO ~> inverse_zero
   618   real_le_refl ~> order_refl
   619   real_le_antisym ~> order_antisym
   620   real_le_trans ~> order_trans
   621   real_le_linear ~> linear
   622   real_le_eq_diff ~> le_iff_diff_le_0
   623   real_add_left_mono ~> add_left_mono
   624   real_mult_order ~> mult_pos_pos
   625   real_mult_less_mono2 ~> mult_strict_left_mono
   626   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   627   real_0_le_divide_iff ~> zero_le_divide_iff
   628   realpow_two_disj ~> power2_eq_iff
   629   real_squared_diff_one_factored ~> square_diff_one_factored
   630   realpow_two_diff ~> square_diff_square_factored
   631   reals_complete2 ~> complete_real
   632   real_sum_squared_expand ~> power2_sum
   633   exp_ln_eq ~> ln_unique
   634   expi_add ~> exp_add
   635   expi_zero ~> exp_zero
   636   lemma_DERIV_subst ~> DERIV_cong
   637   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   638   LIMSEQ_const ~> tendsto_const
   639   LIMSEQ_norm ~> tendsto_norm
   640   LIMSEQ_add ~> tendsto_add
   641   LIMSEQ_minus ~> tendsto_minus
   642   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   643   LIMSEQ_diff ~> tendsto_diff
   644   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   645   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   646   LIMSEQ_mult ~> tendsto_mult
   647   LIMSEQ_inverse ~> tendsto_inverse
   648   LIMSEQ_divide ~> tendsto_divide
   649   LIMSEQ_pow ~> tendsto_power
   650   LIMSEQ_setsum ~> tendsto_setsum
   651   LIMSEQ_setprod ~> tendsto_setprod
   652   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   653   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   654   LIMSEQ_imp_rabs ~> tendsto_rabs
   655   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   656   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   657   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   658   LIMSEQ_Complex ~> tendsto_Complex
   659   LIM_ident ~> tendsto_ident_at
   660   LIM_const ~> tendsto_const
   661   LIM_add ~> tendsto_add
   662   LIM_add_zero ~> tendsto_add_zero
   663   LIM_minus ~> tendsto_minus
   664   LIM_diff ~> tendsto_diff
   665   LIM_norm ~> tendsto_norm
   666   LIM_norm_zero ~> tendsto_norm_zero
   667   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   668   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   669   LIM_rabs ~> tendsto_rabs
   670   LIM_rabs_zero ~> tendsto_rabs_zero
   671   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   672   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   673   LIM_compose ~> tendsto_compose
   674   LIM_mult ~> tendsto_mult
   675   LIM_scaleR ~> tendsto_scaleR
   676   LIM_of_real ~> tendsto_of_real
   677   LIM_power ~> tendsto_power
   678   LIM_inverse ~> tendsto_inverse
   679   LIM_sgn ~> tendsto_sgn
   680   isCont_LIM_compose ~> isCont_tendsto_compose
   681   bounded_linear.LIM ~> bounded_linear.tendsto
   682   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   683   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   684   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   685   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   686   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   687   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   688 
   689 * Theory Complex_Main: The definition of infinite series was
   690 generalized.  Now it is defined on the type class {topological_space,
   691 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   692 
   693 * Theory Complex_Main: The complex exponential function "expi" is now
   694 a type-constrained abbreviation for "exp :: complex => complex"; thus
   695 several polymorphic lemmas about "exp" are now applicable to "expi".
   696 
   697 * Code generation:
   698 
   699   - Theory Library/Code_Char_ord provides native ordering of
   700     characters in the target language.
   701 
   702   - Commands code_module and code_library are legacy, use export_code
   703     instead.
   704 
   705   - Method "evaluation" is legacy, use method "eval" instead.
   706 
   707   - Legacy evaluator "SML" is deactivated by default.  May be
   708     reactivated by the following theory command:
   709 
   710       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   711 
   712 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   713 
   714 * New proof method "induction" that gives induction hypotheses the
   715 name "IH", thus distinguishing them from further hypotheses that come
   716 from rule induction.  The latter are still called "hyps".  Method
   717 "induction" is a thin wrapper around "induct" and follows the same
   718 syntax.
   719 
   720 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
   721 still available as a legacy feature for some time.
   722 
   723 * Nitpick:
   724   - Added "need" and "total_consts" options.
   725   - Reintroduced "show_skolems" option by popular demand.
   726   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   727     INCOMPATIBILITY.
   728 
   729 * Sledgehammer:
   730   - Use quasi-sound (and efficient) translations by default.
   731   - Added support for the following provers: E-ToFoF, LEO-II,
   732     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
   733   - Automatically preplay and minimize proofs before showing them if
   734     this can be done within reasonable time.
   735   - sledgehammer available_provers ~> sledgehammer supported_provers.
   736     INCOMPATIBILITY.
   737   - Added "preplay_timeout", "slicing", "type_enc", "sound",
   738     "max_mono_iters", and "max_new_mono_instances" options.
   739   - Removed "explicit_apply" and "full_types" options as well as "Full
   740     Types" Proof General menu item. INCOMPATIBILITY.
   741 
   742 * Metis:
   743   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   744   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
   745     INCOMPATIBILITY.
   746 
   747 * Command 'try':
   748   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
   749     "elim:" options. INCOMPATIBILITY.
   750   - Introduced 'try' that not only runs 'try_methods' but also
   751     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
   752 
   753 * Quickcheck:
   754   - Added "eval" option to evaluate terms for the found counterexample
   755     (currently only supported by the default (exhaustive) tester).
   756   - Added post-processing of terms to obtain readable counterexamples
   757     (currently only supported by the default (exhaustive) tester).
   758   - New counterexample generator quickcheck[narrowing] enables
   759     narrowing-based testing.  Requires the Glasgow Haskell compiler
   760     with its installation location defined in the Isabelle settings
   761     environment as ISABELLE_GHC.
   762   - Removed quickcheck tester "SML" based on the SML code generator
   763     (formly in HOL/Library).
   764 
   765 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
   766 use 'partial_function' instead.
   767 
   768 * Theory Library/Extended_Reals replaces now the positive extended
   769 reals found in probability theory. This file is extended by
   770 Multivariate_Analysis/Extended_Real_Limits.
   771 
   772 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
   773 from where it must be imported explicitly if it is really required.
   774 INCOMPATIBILITY.
   775 
   776 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
   777 been moved here.  INCOMPATIBILITY.
   778 
   779 * Theory Library/Saturated provides type of numbers with saturated
   780 arithmetic.
   781 
   782 * Theory Library/Product_Lattice defines a pointwise ordering for the
   783 product type 'a * 'b, and provides instance proofs for various order
   784 and lattice type classes.
   785 
   786 * Theory Library/Countable now provides the "countable_datatype" proof
   787 method for proving "countable" class instances for datatypes.
   788 
   789 * Theory Library/Cset_Monad allows do notation for computable sets
   790 (cset) via the generic monad ad-hoc overloading facility.
   791 
   792 * Library: Theories of common data structures are split into theories
   793 for implementation, an invariant-ensuring type, and connection to an
   794 abstract type. INCOMPATIBILITY.
   795 
   796   - RBT is split into RBT and RBT_Mapping.
   797   - AssocList is split and renamed into AList and AList_Mapping.
   798   - DList is split into DList_Impl, DList, and DList_Cset.
   799   - Cset is split into Cset and List_Cset.
   800 
   801 * Theory Library/Nat_Infinity has been renamed to
   802 Library/Extended_Nat, with name changes of the following types and
   803 constants:
   804 
   805   type inat   ~> type enat
   806   Fin         ~> enat
   807   Infty       ~> infinity (overloaded)
   808   iSuc        ~> eSuc
   809   the_Fin     ~> the_enat
   810 
   811 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   812 been renamed accordingly. INCOMPATIBILITY.
   813 
   814 * Session Multivariate_Analysis: The euclidean_space type class now
   815 fixes a constant "Basis :: 'a set" consisting of the standard
   816 orthonormal basis for the type. Users now have the option of
   817 quantifying over this set instead of using the "basis" function, e.g.
   818 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
   819 
   820 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   821 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   822 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   823 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   824 changed to match. Definition theorems for overloaded constants now use
   825 the standard "foo_vec_def" naming scheme. A few other theorems have
   826 been renamed as follows (INCOMPATIBILITY):
   827 
   828   Cart_eq          ~> vec_eq_iff
   829   dist_nth_le_cart ~> dist_vec_nth_le
   830   tendsto_vector   ~> vec_tendstoI
   831   Cauchy_vector    ~> vec_CauchyI
   832 
   833 * Session Multivariate_Analysis: Several duplicate theorems have been
   834 removed, and other theorems have been renamed or replaced with more
   835 general versions. INCOMPATIBILITY.
   836 
   837   finite_choice ~> finite_set_choice
   838   eventually_conjI ~> eventually_conj
   839   eventually_and ~> eventually_conj_iff
   840   eventually_false ~> eventually_False
   841   setsum_norm ~> norm_setsum
   842   Lim_sequentially ~> LIMSEQ_def
   843   Lim_ident_at ~> LIM_ident
   844   Lim_const ~> tendsto_const
   845   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   846   Lim_neg ~> tendsto_minus
   847   Lim_add ~> tendsto_add
   848   Lim_sub ~> tendsto_diff
   849   Lim_mul ~> tendsto_scaleR
   850   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   851   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   852   Lim_linear ~> bounded_linear.tendsto
   853   Lim_component ~> tendsto_euclidean_component
   854   Lim_component_cart ~> tendsto_vec_nth
   855   Lim_inner ~> tendsto_inner [OF tendsto_const]
   856   dot_lsum ~> inner_setsum_left
   857   dot_rsum ~> inner_setsum_right
   858   continuous_cmul ~> continuous_scaleR [OF continuous_const]
   859   continuous_neg ~> continuous_minus
   860   continuous_sub ~> continuous_diff
   861   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
   862   continuous_mul ~> continuous_scaleR
   863   continuous_inv ~> continuous_inverse
   864   continuous_at_within_inv ~> continuous_at_within_inverse
   865   continuous_at_inv ~> continuous_at_inverse
   866   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
   867   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
   868   continuous_at_component ~> continuous_component [OF continuous_at_id]
   869   continuous_on_neg ~> continuous_on_minus
   870   continuous_on_sub ~> continuous_on_diff
   871   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   872   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   873   continuous_on_mul ~> continuous_on_scaleR
   874   continuous_on_mul_real ~> continuous_on_mult
   875   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   876   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
   877   continuous_on_inverse ~> continuous_on_inv
   878   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
   879   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
   880   subset_interior ~> interior_mono
   881   subset_closure ~> closure_mono
   882   closure_univ ~> closure_UNIV
   883   real_arch_lt ~> reals_Archimedean2
   884   real_arch ~> reals_Archimedean3
   885   real_abs_norm ~> abs_norm_cancel
   886   real_abs_sub_norm ~> norm_triangle_ineq3
   887   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
   888 
   889 * Session HOL-Probability:
   890   - Caratheodory's extension lemma is now proved for ring_of_sets.
   891   - Infinite products of probability measures are now available.
   892   - Sigma closure is independent, if the generator is independent
   893   - Use extended reals instead of positive extended
   894     reals. INCOMPATIBILITY.
   895 
   896 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
   897 
   898   expand_fun_below ~> fun_below_iff
   899   below_fun_ext ~> fun_belowI
   900   expand_cfun_eq ~> cfun_eq_iff
   901   ext_cfun ~> cfun_eqI
   902   expand_cfun_below ~> cfun_below_iff
   903   below_cfun_ext ~> cfun_belowI
   904   monofun_fun_fun ~> fun_belowD
   905   monofun_fun_arg ~> monofunE
   906   monofun_lub_fun ~> adm_monofun [THEN admD]
   907   cont_lub_fun ~> adm_cont [THEN admD]
   908   cont2cont_Rep_CFun ~> cont2cont_APP
   909   cont_Rep_CFun_app ~> cont_APP_app
   910   cont_Rep_CFun_app_app ~> cont_APP_app_app
   911   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
   912   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
   913   contlub_cfun ~> lub_APP [symmetric]
   914   contlub_LAM ~> lub_LAM [symmetric]
   915   thelubI ~> lub_eqI
   916   UU_I ~> bottomI
   917   lift_distinct1 ~> lift.distinct(1)
   918   lift_distinct2 ~> lift.distinct(2)
   919   Def_not_UU ~> lift.distinct(2)
   920   Def_inject ~> lift.inject
   921   below_UU_iff ~> below_bottom_iff
   922   eq_UU_iff ~> eq_bottom_iff
   923 
   924 
   925 *** Document preparation ***
   926 
   927 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   928 isar-ref manual, both for description and actual application of the
   929 same.
   930 
   931 * Antiquotation @{value} evaluates the given term and presents its
   932 result.
   933 
   934 * Antiquotations: term style "isub" provides ad-hoc conversion of
   935 variables x1, y23 into subscripted form x\<^isub>1,
   936 y\<^isub>2\<^isub>3.
   937 
   938 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   939 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   940 
   941 * Localized \isabellestyle switch can be used within blocks or groups
   942 like this:
   943 
   944   \isabellestyle{it}  %preferred default
   945   {\isabellestylett @{text "typewriter stuff"}}
   946 
   947 * Discontinued special treatment of hard tabulators.  Implicit
   948 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
   949 layouts.
   950 
   951 
   952 *** ML ***
   953 
   954 * The inner syntax of sort/type/term/prop supports inlined YXML
   955 representations within quoted string tokens.  By encoding logical
   956 entities via Term_XML (in ML or Scala) concrete syntax can be
   957 bypassed, which is particularly useful for producing bits of text
   958 under external program control.
   959 
   960 * Antiquotations for ML and document preparation are managed as theory
   961 data, which requires explicit setup.
   962 
   963 * Isabelle_Process.is_active allows tools to check if the official
   964 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   965 (better known as Proof General).
   966 
   967 * Structure Proof_Context follows standard naming scheme.  Old
   968 ProofContext is still available for some time as legacy alias.
   969 
   970 * Structure Timing provides various operations for timing; supersedes
   971 former start_timing/end_timing etc.
   972 
   973 * Path.print is the official way to show file-system paths to users
   974 (including quotes etc.).
   975 
   976 * Inner syntax: identifiers in parse trees of generic categories
   977 "logic", "aprop", "idt" etc. carry position information (disguised as
   978 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   979 translations that choke on unexpected type constraints.  Positions can
   980 be stripped in ML translations via Syntax.strip_positions /
   981 Syntax.strip_positions_ast, or via the syntax constant
   982 "_strip_positions" within parse trees.  As last resort, positions can
   983 be disabled via the configuration option Syntax.positions, which is
   984 called "syntax_positions" in Isar attribute syntax.
   985 
   986 * Discontinued special status of various ML structures that contribute
   987 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   988 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   989 refer directly to Ast.Constant, Lexicon.is_identifier,
   990 Syntax_Trans.mk_binder_tr etc.
   991 
   992 * Typed print translation: discontinued show_sorts argument, which is
   993 already available via context of "advanced" translation.
   994 
   995 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   996 goal states; body tactic needs to address all subgoals uniformly.
   997 
   998 * Slightly more special eq_list/eq_set, with shortcut involving
   999 pointer equality (assumes that eq relation is reflexive).
  1000 
  1001 * Classical tactics use proper Proof.context instead of historic types
  1002 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  1003 operate directly on Proof.context.  Raw type claset retains its use as
  1004 snapshot of the classical context, which can be recovered via
  1005 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  1006 INCOMPATIBILITY, classical tactics and derived proof methods require
  1007 proper Proof.context.
  1008 
  1009 
  1010 *** System ***
  1011 
  1012 * Discontinued support for Poly/ML 5.2, which was the last version
  1013 without proper multithreading and TimeLimit implementation.
  1014 
  1015 * Discontinued old lib/scripts/polyml-platform, which has been
  1016 obsolete since Isabelle2009-2.
  1017 
  1018 * Various optional external tools are referenced more robustly and
  1019 uniformly by explicit Isabelle settings as follows:
  1020 
  1021   ISABELLE_CSDP   (formerly CSDP_EXE)
  1022   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  1023   ISABELLE_OCAML  (formerly EXEC_OCAML)
  1024   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  1025   ISABELLE_YAP    (formerly EXEC_YAP)
  1026 
  1027 Note that automated detection from the file-system or search path has
  1028 been discontinued.  INCOMPATIBILITY.
  1029 
  1030 * Scala layer provides JVM method invocation service for static
  1031 methods of type (String)String, see Invoke_Scala.method in ML.  For
  1032 example:
  1033 
  1034   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  1035 
  1036 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  1037 this allows to pass structured values between ML and Scala.
  1038 
  1039 * The IsabelleText fonts includes some further glyphs to support the
  1040 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  1041 installed a local copy (which is normally *not* required) need to
  1042 delete or update it from ~~/lib/fonts/.
  1043 
  1044 
  1045 
  1046 New in Isabelle2011 (January 2011)
  1047 ----------------------------------
  1048 
  1049 *** General ***
  1050 
  1051 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  1052 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  1053 useful tooltips and hyperlinks produced from its static analysis.  The
  1054 bundled component provides an executable Isabelle tool that can be run
  1055 like this:
  1056 
  1057   Isabelle2011/bin/isabelle jedit
  1058 
  1059 * Significantly improved Isabelle/Isar implementation manual.
  1060 
  1061 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  1062 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  1063 while the default heap location within that directory lacks that extra
  1064 suffix.  This isolates multiple Isabelle installations from each
  1065 other, avoiding problems with old settings in new versions.
  1066 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  1067 
  1068 * Source files are always encoded as UTF-8, instead of old-fashioned
  1069 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  1070 the following package declarations:
  1071 
  1072   \usepackage[utf8]{inputenc}
  1073   \usepackage{textcomp}
  1074 
  1075 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  1076 a Unicode character is treated as a single symbol, not a sequence of
  1077 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  1078 contain symbols without further backslash escapes, Unicode can now be
  1079 used here as well.  Recall that Symbol.explode in ML provides a
  1080 consistent view on symbols, while raw explode (or String.explode)
  1081 merely give a byte-oriented representation.
  1082 
  1083 * Theory loader: source files are primarily located via the master
  1084 directory of each theory node (where the .thy file itself resides).
  1085 The global load path is still partially available as legacy feature.
  1086 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  1087 explicit paths, relatively to the theory.
  1088 
  1089 * Special treatment of ML file names has been discontinued.
  1090 Historically, optional extensions .ML or .sml were added on demand --
  1091 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  1092 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  1093 
  1094 * Various options that affect pretty printing etc. are now properly
  1095 handled within the context via configuration options, instead of
  1096 unsynchronized references or print modes.  There are both ML Config.T
  1097 entities and Isar declaration attributes to access these.
  1098 
  1099   ML (Config.T)                 Isar (attribute)
  1100 
  1101   eta_contract                  eta_contract
  1102   show_brackets                 show_brackets
  1103   show_sorts                    show_sorts
  1104   show_types                    show_types
  1105   show_question_marks           show_question_marks
  1106   show_consts                   show_consts
  1107   show_abbrevs                  show_abbrevs
  1108 
  1109   Syntax.ast_trace              syntax_ast_trace
  1110   Syntax.ast_stat               syntax_ast_stat
  1111   Syntax.ambiguity_level        syntax_ambiguity_level
  1112 
  1113   Goal_Display.goals_limit      goals_limit
  1114   Goal_Display.show_main_goal   show_main_goal
  1115 
  1116   Method.rule_trace             rule_trace
  1117 
  1118   Thy_Output.display            thy_output_display
  1119   Thy_Output.quotes             thy_output_quotes
  1120   Thy_Output.indent             thy_output_indent
  1121   Thy_Output.source             thy_output_source
  1122   Thy_Output.break              thy_output_break
  1123 
  1124 Note that corresponding "..._default" references in ML may only be
  1125 changed globally at the ROOT session setup, but *not* within a theory.
  1126 The option "show_abbrevs" supersedes the former print mode
  1127 "no_abbrevs" with inverted meaning.
  1128 
  1129 * More systematic naming of some configuration options.
  1130 INCOMPATIBILITY.
  1131 
  1132   trace_simp  ~>  simp_trace
  1133   debug_simp  ~>  simp_debug
  1134 
  1135 * Support for real valued configuration options, using simplistic
  1136 floating-point notation that coincides with the inner syntax for
  1137 float_token.
  1138 
  1139 * Support for real valued preferences (with approximative PGIP type):
  1140 front-ends need to accept "pgint" values in float notation.
  1141 INCOMPATIBILITY.
  1142 
  1143 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  1144 DejaVu Sans.
  1145 
  1146 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  1147 
  1148 
  1149 *** Pure ***
  1150 
  1151 * Command 'type_synonym' (with single argument) replaces somewhat
  1152 outdated 'types', which is still available as legacy feature for some
  1153 time.
  1154 
  1155 * Command 'nonterminal' (with 'and' separated list of arguments)
  1156 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  1157 
  1158 * Command 'notepad' replaces former 'example_proof' for
  1159 experimentation in Isar without any result.  INCOMPATIBILITY.
  1160 
  1161 * Locale interpretation commands 'interpret' and 'sublocale' accept
  1162 lists of equations to map definitions in a locale to appropriate
  1163 entities in the context of the interpretation.  The 'interpretation'
  1164 command already provided this functionality.
  1165 
  1166 * Diagnostic command 'print_dependencies' prints the locale instances
  1167 that would be activated if the specified expression was interpreted in
  1168 the current context.  Variant "print_dependencies!" assumes a context
  1169 without interpretations.
  1170 
  1171 * Diagnostic command 'print_interps' prints interpretations in proofs
  1172 in addition to interpretations in theories.
  1173 
  1174 * Discontinued obsolete 'global' and 'local' commands to manipulate
  1175 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  1176 Sign.root_path and Sign.local_path may be applied directly where this
  1177 feature is still required for historical reasons.
  1178 
  1179 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  1180 'definition' instead.
  1181 
  1182 * The "prems" fact, which refers to the accidental collection of
  1183 foundational premises in the context, is now explicitly marked as
  1184 legacy feature and will be discontinued soon.  Consider using "assms"
  1185 of the head statement or reference facts by explicit names.
  1186 
  1187 * Document antiquotations @{class} and @{type} print classes and type
  1188 constructors.
  1189 
  1190 * Document antiquotation @{file} checks file/directory entries within
  1191 the local file system.
  1192 
  1193 
  1194 *** HOL ***
  1195 
  1196 * Coercive subtyping: functions can be declared as coercions and type
  1197 inference will add them as necessary upon input of a term.  Theory
  1198 Complex_Main declares real :: nat => real and real :: int => real as
  1199 coercions. A coercion function f is declared like this:
  1200 
  1201   declare [[coercion f]]
  1202 
  1203 To lift coercions through type constructors (e.g. from nat => real to
  1204 nat list => real list), map functions can be declared, e.g.
  1205 
  1206   declare [[coercion_map map]]
  1207 
  1208 Currently coercion inference is activated only in theories including
  1209 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1210 the configuration option "coercion_enabled", e.g. it can be enabled in
  1211 other theories like this:
  1212 
  1213   declare [[coercion_enabled]]
  1214 
  1215 * Command 'partial_function' provides basic support for recursive
  1216 function definitions over complete partial orders.  Concrete instances
  1217 are provided for i) the option type, ii) tail recursion on arbitrary
  1218 types, and iii) the heap monad of Imperative_HOL.  See
  1219 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1220 for examples.
  1221 
  1222 * Function package: f.psimps rules are no longer implicitly declared
  1223 as [simp].  INCOMPATIBILITY.
  1224 
  1225 * Datatype package: theorems generated for executable equality (class
  1226 "eq") carry proper names and are treated as default code equations.
  1227 
  1228 * Inductive package: now offers command 'inductive_simps' to
  1229 automatically derive instantiated and simplified equations for
  1230 inductive predicates, similar to 'inductive_cases'.
  1231 
  1232 * Command 'enriched_type' allows to register properties of the
  1233 functorial structure of types.
  1234 
  1235 * Improved infrastructure for term evaluation using code generator
  1236 techniques, in particular static evaluation conversions.
  1237 
  1238 * Code generator: Scala (2.8 or higher) has been added to the target
  1239 languages.
  1240 
  1241 * Code generator: globbing constant expressions "*" and "Theory.*"
  1242 have been replaced by the more idiomatic "_" and "Theory._".
  1243 INCOMPATIBILITY.
  1244 
  1245 * Code generator: export_code without explicit file declaration prints
  1246 to standard output.  INCOMPATIBILITY.
  1247 
  1248 * Code generator: do not print function definitions for case
  1249 combinators any longer.
  1250 
  1251 * Code generator: simplification with rules determined with
  1252 src/Tools/Code/code_simp.ML and method "code_simp".
  1253 
  1254 * Code generator for records: more idiomatic representation of record
  1255 types.  Warning: records are not covered by ancient SML code
  1256 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1257 rep_datatype declaration helps to succeed then:
  1258 
  1259   record 'a foo = ...
  1260   ...
  1261   rep_datatype foo_ext ...
  1262 
  1263 * Records: logical foundation type for records does not carry a
  1264 '_type' suffix any longer (obsolete due to authentic syntax).
  1265 INCOMPATIBILITY.
  1266 
  1267 * Quickcheck now by default uses exhaustive testing instead of random
  1268 testing.  Random testing can be invoked by "quickcheck [random]",
  1269 exhaustive testing by "quickcheck [exhaustive]".
  1270 
  1271 * Quickcheck instantiates polymorphic types with small finite
  1272 datatypes by default. This enables a simple execution mechanism to
  1273 handle quantifiers and function equality over the finite datatypes.
  1274 
  1275 * Quickcheck random generator has been renamed from "code" to
  1276 "random".  INCOMPATIBILITY.
  1277 
  1278 * Quickcheck now has a configurable time limit which is set to 30
  1279 seconds by default. This can be changed by adding [timeout = n] to the
  1280 quickcheck command. The time limit for Auto Quickcheck is still set
  1281 independently.
  1282 
  1283 * Quickcheck in locales considers interpretations of that locale for
  1284 counter example search.
  1285 
  1286 * Sledgehammer:
  1287   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1288     method. See the Sledgehammer manual for details ("isabelle doc
  1289     sledgehammer").
  1290   - Renamed commands:
  1291     sledgehammer atp_info ~> sledgehammer running_provers
  1292     sledgehammer atp_kill ~> sledgehammer kill_provers
  1293     sledgehammer available_atps ~> sledgehammer available_provers
  1294     INCOMPATIBILITY.
  1295   - Renamed options:
  1296     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1297     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1298     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1299     (and "ms" and "min" are no longer supported)
  1300     INCOMPATIBILITY.
  1301 
  1302 * Nitpick:
  1303   - Renamed options:
  1304     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1305     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1306     INCOMPATIBILITY.
  1307   - Added support for partial quotient types.
  1308   - Added local versions of the "Nitpick.register_xxx" functions.
  1309   - Added "whack" option.
  1310   - Allow registration of quotient types as codatatypes.
  1311   - Improved "merge_type_vars" option to merge more types.
  1312   - Removed unsound "fast_descrs" option.
  1313   - Added custom symmetry breaking for datatypes, making it possible to reach
  1314     higher cardinalities.
  1315   - Prevent the expansion of too large definitions.
  1316 
  1317 * Proof methods "metis" and "meson" now have configuration options
  1318 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1319 to diagnose these tools. E.g.
  1320 
  1321     using [[metis_trace = true]]
  1322 
  1323 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1324 manually as command 'solve_direct'.
  1325 
  1326 * The default SMT solver Z3 must be enabled explicitly (due to
  1327 licensing issues) by setting the environment variable
  1328 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1329 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1330 changing the SMT solver is done via the configuration option
  1331 "smt_solver".
  1332 
  1333 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1334 i.e. "remote_cvc3" and "remote_z3".
  1335 
  1336 * Added basic SMT support for datatypes, records, and typedefs using
  1337 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1338 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1339 support for a similar behavior).  Minor INCOMPATIBILITY.
  1340 
  1341 * Changed SMT configuration options:
  1342   - Renamed:
  1343     z3_proofs ~> smt_oracle (with inverted meaning)
  1344     z3_trace_assms ~> smt_trace_used_facts
  1345     INCOMPATIBILITY.
  1346   - Added:
  1347     smt_verbose
  1348     smt_random_seed
  1349     smt_datatypes
  1350     smt_infer_triggers
  1351     smt_monomorph_limit
  1352     cvc3_options
  1353     remote_cvc3_options
  1354     remote_z3_options
  1355     yices_options
  1356 
  1357 * Boogie output files (.b2i files) need to be declared in the theory
  1358 header.
  1359 
  1360 * Simplification procedure "list_to_set_comprehension" rewrites list
  1361 comprehensions applied to List.set to set comprehensions.  Occasional
  1362 INCOMPATIBILITY, may be deactivated like this:
  1363 
  1364   declare [[simproc del: list_to_set_comprehension]]
  1365 
  1366 * Removed old version of primrec package.  INCOMPATIBILITY.
  1367 
  1368 * Removed simplifier congruence rule of "prod_case", as has for long
  1369 been the case with "split".  INCOMPATIBILITY.
  1370 
  1371 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1372 
  1373 * Removed [split_format ... and ... and ...] version of
  1374 [split_format].  Potential INCOMPATIBILITY.
  1375 
  1376 * Predicate "sorted" now defined inductively, with nice induction
  1377 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1378 
  1379 * Constant "contents" renamed to "the_elem", to free the generic name
  1380 contents for other uses.  INCOMPATIBILITY.
  1381 
  1382 * Renamed class eq and constant eq (for code generation) to class
  1383 equal and constant equal, plus renaming of related facts and various
  1384 tuning.  INCOMPATIBILITY.
  1385 
  1386 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1387 
  1388 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1389 INCOMPATIBILITY.
  1390 
  1391 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1392 avoid confusion with finite sets.  INCOMPATIBILITY.
  1393 
  1394 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1395 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1396 for congruent(2)).
  1397 
  1398 * Some previously unqualified names have been qualified:
  1399 
  1400   types
  1401     bool ~> HOL.bool
  1402     nat ~> Nat.nat
  1403 
  1404   constants
  1405     Trueprop ~> HOL.Trueprop
  1406     True ~> HOL.True
  1407     False ~> HOL.False
  1408     op & ~> HOL.conj
  1409     op | ~> HOL.disj
  1410     op --> ~> HOL.implies
  1411     op = ~> HOL.eq
  1412     Not ~> HOL.Not
  1413     The ~> HOL.The
  1414     All ~> HOL.All
  1415     Ex ~> HOL.Ex
  1416     Ex1 ~> HOL.Ex1
  1417     Let ~> HOL.Let
  1418     If ~> HOL.If
  1419     Ball ~> Set.Ball
  1420     Bex ~> Set.Bex
  1421     Suc ~> Nat.Suc
  1422     Pair ~> Product_Type.Pair
  1423     fst ~> Product_Type.fst
  1424     snd ~> Product_Type.snd
  1425     curry ~> Product_Type.curry
  1426     op : ~> Set.member
  1427     Collect ~> Set.Collect
  1428 
  1429 INCOMPATIBILITY.
  1430 
  1431 * More canonical naming convention for some fundamental definitions:
  1432 
  1433     bot_bool_eq ~> bot_bool_def
  1434     top_bool_eq ~> top_bool_def
  1435     inf_bool_eq ~> inf_bool_def
  1436     sup_bool_eq ~> sup_bool_def
  1437     bot_fun_eq  ~> bot_fun_def
  1438     top_fun_eq  ~> top_fun_def
  1439     inf_fun_eq  ~> inf_fun_def
  1440     sup_fun_eq  ~> sup_fun_def
  1441 
  1442 INCOMPATIBILITY.
  1443 
  1444 * More stylized fact names:
  1445 
  1446   expand_fun_eq ~> fun_eq_iff
  1447   expand_set_eq ~> set_eq_iff
  1448   set_ext       ~> set_eqI
  1449   nat_number    ~> eval_nat_numeral
  1450 
  1451 INCOMPATIBILITY.
  1452 
  1453 * Refactoring of code-generation specific operations in theory List:
  1454 
  1455   constants
  1456     null ~> List.null
  1457 
  1458   facts
  1459     mem_iff ~> member_def
  1460     null_empty ~> null_def
  1461 
  1462 INCOMPATIBILITY.  Note that these were not supposed to be used
  1463 regularly unless for striking reasons; their main purpose was code
  1464 generation.
  1465 
  1466 Various operations from the Haskell prelude are used for generating
  1467 Haskell code.
  1468 
  1469 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1470 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1471 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1472 
  1473 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1474 "*" and "+" respectively.  INCOMPATIBILITY.
  1475 
  1476 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1477 "Sum_Type.Plus" instead.
  1478 
  1479 * Constant "split" has been merged with constant "prod_case"; names of
  1480 ML functions, facts etc. involving split have been retained so far,
  1481 though.  INCOMPATIBILITY.
  1482 
  1483 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1484 instead.  INCOMPATIBILITY.
  1485 
  1486 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1487 INCOMPATIBILITY.
  1488 
  1489 * Former theory Library/Enum is now part of the HOL-Main image.
  1490 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1491 referred to by its qualified name.
  1492 
  1493   enum    ~>  Enum.enum
  1494   nlists  ~>  Enum.nlists
  1495   product ~>  Enum.product
  1496 
  1497 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1498 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1499 INCOMPATIBILITY.
  1500 
  1501 * Theory Library/SetsAndFunctions has been split into
  1502 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1503 for instance definitions for functions; various improvements.
  1504 INCOMPATIBILITY.
  1505 
  1506 * Theory Library/Multiset provides stable quicksort implementation of
  1507 sort_key.
  1508 
  1509 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1510 INCOMPATIBILITY.
  1511 
  1512 * Session Multivariate_Analysis: introduced a type class for euclidean
  1513 space.  Most theorems are now stated in terms of euclidean spaces
  1514 instead of finite cartesian products.
  1515 
  1516   types
  1517     real ^ 'n ~>  'a::real_vector
  1518               ~>  'a::euclidean_space
  1519               ~>  'a::ordered_euclidean_space
  1520         (depends on your needs)
  1521 
  1522   constants
  1523      _ $ _        ~> _ $$ _
  1524      \<chi> x. _  ~> \<chi>\<chi> x. _
  1525      CARD('n)     ~> DIM('a)
  1526 
  1527 Also note that the indices are now natural numbers and not from some
  1528 finite type. Finite cartesian products of euclidean spaces, products
  1529 of euclidean spaces the real and complex numbers are instantiated to
  1530 be euclidean_spaces.  INCOMPATIBILITY.
  1531 
  1532 * Session Probability: introduced pextreal as positive extended real
  1533 numbers.  Use pextreal as value for measures.  Introduce the
  1534 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1535 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1536 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1537 
  1538 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1539 INCOMPATIBILITY.
  1540 
  1541 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1542 prove verification conditions generated by the SPARK Ada program
  1543 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1544 
  1545 
  1546 *** HOL-Algebra ***
  1547 
  1548 * Theorems for additive ring operations (locale abelian_monoid and
  1549 descendants) are generated by interpretation from their multiplicative
  1550 counterparts.  Names (in particular theorem names) have the mandatory
  1551 qualifier 'add'.  Previous theorem names are redeclared for
  1552 compatibility.
  1553 
  1554 * Structure "int_ring" is now an abbreviation (previously a
  1555 definition).  This fits more natural with advanced interpretations.
  1556 
  1557 
  1558 *** HOLCF ***
  1559 
  1560 * The domain package now runs in definitional mode by default: The
  1561 former command 'new_domain' is now called 'domain'.  To use the domain
  1562 package in its original axiomatic mode, use 'domain (unsafe)'.
  1563 INCOMPATIBILITY.
  1564 
  1565 * The new class "domain" is now the default sort.  Class "predomain"
  1566 is an unpointed version of "domain". Theories can be updated by
  1567 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1568 
  1569   'a::type ~> 'a::countable
  1570   'a::cpo  ~> 'a::predomain
  1571   'a::pcpo ~> 'a::domain
  1572 
  1573 * The old type class "rep" has been superseded by class "domain".
  1574 Accordingly, users of the definitional package must remove any
  1575 "default_sort rep" declarations.  INCOMPATIBILITY.
  1576 
  1577 * The domain package (definitional mode) now supports unpointed
  1578 predomain argument types, as long as they are marked 'lazy'. (Strict
  1579 arguments must be in class "domain".) For example, the following
  1580 domain definition now works:
  1581 
  1582   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1583 
  1584 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1585 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1586 'a option, and 'a list.  Additionally, it configures fixrec and the
  1587 domain package to work with these types.  For example:
  1588 
  1589   fixrec isInl :: "('a + 'b) u -> tr"
  1590     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1591 
  1592   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1593 
  1594 * The "(permissive)" option of fixrec has been replaced with a
  1595 per-equation "(unchecked)" option. See
  1596 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1597 
  1598 * The "bifinite" class no longer fixes a constant "approx"; the class
  1599 now just asserts that such a function exists.  INCOMPATIBILITY.
  1600 
  1601 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1602 defines an embedding of type 'a defl into udom by default; instances
  1603 of "bifinite" and "domain" classes are available in
  1604 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1605 
  1606 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1607 
  1608 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1609 
  1610 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1611 
  1612 * The function "cprod_map" has been renamed to "prod_map".
  1613 INCOMPATIBILITY.
  1614 
  1615 * The monadic bind operator on each powerdomain has new binder syntax
  1616 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1617 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1618 
  1619 * The infix syntax for binary union on each powerdomain has changed
  1620 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1621 syntax.  INCOMPATIBILITY.
  1622 
  1623 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1624 still supported as an input translation.
  1625 
  1626 * Renamed some theorems (the original names are also still available).
  1627 
  1628   expand_fun_below   ~> fun_below_iff
  1629   below_fun_ext      ~> fun_belowI
  1630   expand_cfun_eq     ~> cfun_eq_iff
  1631   ext_cfun           ~> cfun_eqI
  1632   expand_cfun_below  ~> cfun_below_iff
  1633   below_cfun_ext     ~> cfun_belowI
  1634   cont2cont_Rep_CFun ~> cont2cont_APP
  1635 
  1636 * The Abs and Rep functions for various types have changed names.
  1637 Related theorem names have also changed to match. INCOMPATIBILITY.
  1638 
  1639   Rep_CFun  ~> Rep_cfun
  1640   Abs_CFun  ~> Abs_cfun
  1641   Rep_Sprod ~> Rep_sprod
  1642   Abs_Sprod ~> Abs_sprod
  1643   Rep_Ssum  ~> Rep_ssum
  1644   Abs_Ssum  ~> Abs_ssum
  1645 
  1646 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1647 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1648 
  1649 * Various changes to bisimulation/coinduction with domain package:
  1650 
  1651   - Definitions of "bisim" constants no longer mention definedness.
  1652   - With mutual recursion, "bisim" predicate is now curried.
  1653   - With mutual recursion, each type gets a separate coind theorem.
  1654   - Variable names in bisim_def and coinduct rules have changed.
  1655 
  1656 INCOMPATIBILITY.
  1657 
  1658 * Case combinators generated by the domain package for type "foo" are
  1659 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1660 
  1661 * Several theorems have been renamed to more accurately reflect the
  1662 names of constants and types involved.  INCOMPATIBILITY.
  1663 
  1664   thelub_const    ~> lub_const
  1665   lub_const       ~> is_lub_const
  1666   thelubI         ~> lub_eqI
  1667   is_lub_lub      ~> is_lubD2
  1668   lubI            ~> is_lub_lub
  1669   unique_lub      ~> is_lub_unique
  1670   is_ub_lub       ~> is_lub_rangeD1
  1671   lub_bin_chain   ~> is_lub_bin_chain
  1672   lub_fun         ~> is_lub_fun
  1673   thelub_fun      ~> lub_fun
  1674   thelub_cfun     ~> lub_cfun
  1675   thelub_Pair     ~> lub_Pair
  1676   lub_cprod       ~> is_lub_prod
  1677   thelub_cprod    ~> lub_prod
  1678   minimal_cprod   ~> minimal_prod
  1679   inst_cprod_pcpo ~> inst_prod_pcpo
  1680   UU_I            ~> bottomI
  1681   compact_UU      ~> compact_bottom
  1682   deflation_UU    ~> deflation_bottom
  1683   finite_deflation_UU ~> finite_deflation_bottom
  1684 
  1685 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1686 
  1687   sq_ord_less_eq_trans ~> below_eq_trans
  1688   sq_ord_eq_less_trans ~> eq_below_trans
  1689   refl_less            ~> below_refl
  1690   trans_less           ~> below_trans
  1691   antisym_less         ~> below_antisym
  1692   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1693   box_less             ~> box_below
  1694   rev_trans_less       ~> rev_below_trans
  1695   not_less2not_eq      ~> not_below2not_eq
  1696   less_UU_iff          ~> below_UU_iff
  1697   flat_less_iff        ~> flat_below_iff
  1698   adm_less             ~> adm_below
  1699   adm_not_less         ~> adm_not_below
  1700   adm_compact_not_less ~> adm_compact_not_below
  1701   less_fun_def         ~> below_fun_def
  1702   expand_fun_less      ~> fun_below_iff
  1703   less_fun_ext         ~> fun_belowI
  1704   less_discr_def       ~> below_discr_def
  1705   discr_less_eq        ~> discr_below_eq
  1706   less_unit_def        ~> below_unit_def
  1707   less_cprod_def       ~> below_prod_def
  1708   prod_lessI           ~> prod_belowI
  1709   Pair_less_iff        ~> Pair_below_iff
  1710   fst_less_iff         ~> fst_below_iff
  1711   snd_less_iff         ~> snd_below_iff
  1712   expand_cfun_less     ~> cfun_below_iff
  1713   less_cfun_ext        ~> cfun_belowI
  1714   injection_less       ~> injection_below
  1715   less_up_def          ~> below_up_def
  1716   not_Iup_less         ~> not_Iup_below
  1717   Iup_less             ~> Iup_below
  1718   up_less              ~> up_below
  1719   Def_inject_less_eq   ~> Def_below_Def
  1720   Def_less_is_eq       ~> Def_below_iff
  1721   spair_less_iff       ~> spair_below_iff
  1722   less_sprod           ~> below_sprod
  1723   spair_less           ~> spair_below
  1724   sfst_less_iff        ~> sfst_below_iff
  1725   ssnd_less_iff        ~> ssnd_below_iff
  1726   fix_least_less       ~> fix_least_below
  1727   dist_less_one        ~> dist_below_one
  1728   less_ONE             ~> below_ONE
  1729   ONE_less_iff         ~> ONE_below_iff
  1730   less_sinlD           ~> below_sinlD
  1731   less_sinrD           ~> below_sinrD
  1732 
  1733 
  1734 *** FOL and ZF ***
  1735 
  1736 * All constant names are now qualified internally and use proper
  1737 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1738 
  1739 *** ZF ***
  1740 
  1741 * Greater support for structured proofs involving induction or case analysis.
  1742 
  1743 * Much greater use of special symbols.
  1744 
  1745 * Removal of many ML theorem bindings. INCOMPATIBILITY.
  1746 
  1747 *** ML ***
  1748 
  1749 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1750 Fail if the argument is false.  Due to inlining the source position of
  1751 failed assertions is included in the error output.
  1752 
  1753 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1754 text is in practice always evaluated with a stable theory checkpoint.
  1755 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1756 
  1757 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1758 the current context, not any accidental theory loader state as before.
  1759 Potential INCOMPATIBILITY, subtle change in semantics.
  1760 
  1761 * Syntax.pretty_priority (default 0) configures the required priority
  1762 of pretty-printed output and thus affects insertion of parentheses.
  1763 
  1764 * Syntax.default_root (default "any") configures the inner syntax
  1765 category (nonterminal symbol) for parsing of terms.
  1766 
  1767 * Former exception Library.UnequalLengths now coincides with
  1768 ListPair.UnequalLengths.
  1769 
  1770 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1771 main functionality is provided by structure Simplifier.
  1772 
  1773 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1774 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1775 almost all situations.
  1776 
  1777 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1778 See implementation manual for further details on exceptions in
  1779 Isabelle/ML.
  1780 
  1781 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1782 meaning.
  1783 
  1784 * Renamed structure PureThy to Pure_Thy and moved most of its
  1785 operations to structure Global_Theory, to emphasize that this is
  1786 rarely-used global-only stuff.
  1787 
  1788 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1789 instead (or tracing for high-volume output).
  1790 
  1791 * Configuration option show_question_marks only affects regular pretty
  1792 printing of types and terms, not raw Term.string_of_vname.
  1793 
  1794 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1795 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1796 @{thms} for most purposes.
  1797 
  1798 * ML structure Unsynchronized is never opened, not even in Isar
  1799 interaction mode as before.  Old Unsynchronized.set etc. have been
  1800 discontinued -- use plain := instead.  This should be *rare* anyway,
  1801 since modern tools always work via official context data, notably
  1802 configuration options.
  1803 
  1804 * Parallel and asynchronous execution requires special care concerning
  1805 interrupts.  Structure Exn provides some convenience functions that
  1806 avoid working directly with raw Interrupt.  User code must not absorb
  1807 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1808 followed by re-raising of the original exception.  Another common
  1809 source of mistakes are "handle _" patterns, which make the meaning of
  1810 the program subject to physical effects of the environment.
  1811 
  1812 
  1813 
  1814 New in Isabelle2009-2 (June 2010)
  1815 ---------------------------------
  1816 
  1817 *** General ***
  1818 
  1819 * Authentic syntax for *all* logical entities (type classes, type
  1820 constructors, term constants): provides simple and robust
  1821 correspondence between formal entities and concrete syntax.  Within
  1822 the parse tree / AST representations, "constants" are decorated by
  1823 their category (class, type, const) and spelled out explicitly with
  1824 their full internal name.
  1825 
  1826 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1827 and translations (translation rules and translation functions in ML).
  1828 Some hints on upgrading:
  1829 
  1830   - Many existing uses of 'syntax' and 'translations' can be replaced
  1831     by more modern 'type_notation', 'notation' and 'abbreviation',
  1832     which are independent of this issue.
  1833 
  1834   - 'translations' require markup within the AST; the term syntax
  1835     provides the following special forms:
  1836 
  1837       CONST c   -- produces syntax version of constant c from context
  1838       XCONST c  -- literally c, checked as constant from context
  1839       c         -- literally c, if declared by 'syntax'
  1840 
  1841     Plain identifiers are treated as AST variables -- occasionally the
  1842     system indicates accidental variables via the error "rhs contains
  1843     extra variables".
  1844 
  1845     Type classes and type constructors are marked according to their
  1846     concrete syntax.  Some old translations rules need to be written
  1847     for the "type" category, using type constructor application
  1848     instead of pseudo-term application of the default category
  1849     "logic".
  1850 
  1851   - 'parse_translation' etc. in ML may use the following
  1852     antiquotations:
  1853 
  1854       @{class_syntax c}   -- type class c within parse tree / AST
  1855       @{term_syntax c}    -- type constructor c within parse tree / AST
  1856       @{const_syntax c}   -- ML version of "CONST c" above
  1857       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1858 
  1859   - Literal types within 'typed_print_translations', i.e. those *not*
  1860     represented as pseudo-terms are represented verbatim.  Use @{class
  1861     c} or @{type_name c} here instead of the above syntax
  1862     antiquotations.
  1863 
  1864 Note that old non-authentic syntax was based on unqualified base
  1865 names, so all of the above "constant" names would coincide.  Recall
  1866 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1867 diagnose syntax problems.
  1868 
  1869 * Type constructors admit general mixfix syntax, not just infix.
  1870 
  1871 * Concrete syntax may be attached to local entities without a proof
  1872 body, too.  This works via regular mixfix annotations for 'fix',
  1873 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1874 similar to the 'notation' command in theory specifications.
  1875 
  1876 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1877 need to specify constant name and syntax separately.  Internal ML
  1878 datatype constructors have been renamed from InfixName to Infix etc.
  1879 Minor INCOMPATIBILITY.
  1880 
  1881 * Schematic theorem statements need to be explicitly markup as such,
  1882 via commands 'schematic_lemma', 'schematic_theorem',
  1883 'schematic_corollary'.  Thus the relevance of the proof is made
  1884 syntactically clear, which impacts performance in a parallel or
  1885 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1886 
  1887 * Use of cumulative prems via "!" in some proof methods has been
  1888 discontinued (old legacy feature).
  1889 
  1890 * References 'trace_simp' and 'debug_simp' have been replaced by
  1891 configuration options stored in the context. Enabling tracing (the
  1892 case of debugging is similar) in proofs works via
  1893 
  1894   using [[trace_simp = true]]
  1895 
  1896 Tracing is then active for all invocations of the simplifier in
  1897 subsequent goal refinement steps. Tracing may also still be enabled or
  1898 disabled via the ProofGeneral settings menu.
  1899 
  1900 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1901 'hide_fact' replace the former 'hide' KIND command.  Minor
  1902 INCOMPATIBILITY.
  1903 
  1904 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1905 more efficient than combinations with -q1 or -q2.
  1906 
  1907 
  1908 *** Pure ***
  1909 
  1910 * Proofterms record type-class reasoning explicitly, using the
  1911 "unconstrain" operation internally.  This eliminates all sort
  1912 constraints from a theorem and proof, introducing explicit
  1913 OFCLASS-premises.  On the proof term level, this operation is
  1914 automatically applied at theorem boundaries, such that closed proofs
  1915 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1916 inspect proof terms.
  1917 
  1918 * Local theory specifications may depend on extra type variables that
  1919 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1920 are added internally.  For example:
  1921 
  1922   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1923 
  1924 * Predicates of locales introduced by classes carry a mandatory
  1925 "class" prefix.  INCOMPATIBILITY.
  1926 
  1927 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1928 
  1929 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1930 'class' instead.
  1931 
  1932 * Command 'code_reflect' allows to incorporate generated ML code into
  1933 runtime environment; replaces immature code_datatype antiquotation.
  1934 INCOMPATIBILITY.
  1935 
  1936 * Code generator: simple concept for abstract datatypes obeying
  1937 invariants.
  1938 
  1939 * Code generator: details of internal data cache have no impact on the
  1940 user space functionality any longer.
  1941 
  1942 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1943 subgoals.  This is more appropriate for interpretations with 'where'.
  1944 INCOMPATIBILITY.
  1945 
  1946 * Command 'example_proof' opens an empty proof body.  This allows to
  1947 experiment with Isar, without producing any persistent result.
  1948 
  1949 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1950 within a local theory context, with explicit checking of the
  1951 constructors involved (in contrast to the raw 'syntax' versions).
  1952 
  1953 * Commands 'types' and 'typedecl' now work within a local theory
  1954 context -- without introducing dependencies on parameters or
  1955 assumptions, which is not possible in Isabelle/Pure.
  1956 
  1957 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1958 within a local theory context.  Minor INCOMPATIBILITY.
  1959 
  1960 
  1961 *** HOL ***
  1962 
  1963 * Command 'typedef' now works within a local theory context -- without
  1964 introducing dependencies on parameters or assumptions, which is not
  1965 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1966 contain multiple interpretations of local typedefs (with different
  1967 non-emptiness proofs), even in a global theory context.
  1968 
  1969 * New package for quotient types.  Commands 'quotient_type' and
  1970 'quotient_definition' may be used for defining types and constants by
  1971 quotient constructions.  An example is the type of integers created by
  1972 quotienting pairs of natural numbers:
  1973 
  1974   fun
  1975     intrel :: "(nat * nat) => (nat * nat) => bool"
  1976   where
  1977     "intrel (x, y) (u, v) = (x + v = u + y)"
  1978 
  1979   quotient_type int = "nat * nat" / intrel
  1980     by (auto simp add: equivp_def expand_fun_eq)
  1981 
  1982   quotient_definition
  1983     "0::int" is "(0::nat, 0::nat)"
  1984 
  1985 The method "lifting" can be used to lift of theorems from the
  1986 underlying "raw" type to the quotient type.  The example
  1987 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1988 construction and provides a reasoning infrastructure for finite sets.
  1989 
  1990 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1991 clash with new theory Quotient in Main HOL.
  1992 
  1993 * Moved the SMT binding into the main HOL session, eliminating
  1994 separate HOL-SMT session.
  1995 
  1996 * List membership infix mem operation is only an input abbreviation.
  1997 INCOMPATIBILITY.
  1998 
  1999 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  2000 for future developements; former Library/Word.thy is still present in
  2001 the AFP entry RSAPPS.
  2002 
  2003 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  2004 longer shadowed.  INCOMPATIBILITY.
  2005 
  2006 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  2007 INCOMPATIBILITY.
  2008 
  2009 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  2010 INCOMPATIBILITY.
  2011 
  2012 * Dropped normalizing_semiring etc; use the facts in semiring classes
  2013 instead.  INCOMPATIBILITY.
  2014 
  2015 * Dropped several real-specific versions of lemmas about floor and
  2016 ceiling; use the generic lemmas from theory "Archimedean_Field"
  2017 instead.  INCOMPATIBILITY.
  2018 
  2019   floor_number_of_eq         ~> floor_number_of
  2020   le_floor_eq_number_of      ~> number_of_le_floor
  2021   le_floor_eq_zero           ~> zero_le_floor
  2022   le_floor_eq_one            ~> one_le_floor
  2023   floor_less_eq_number_of    ~> floor_less_number_of
  2024   floor_less_eq_zero         ~> floor_less_zero
  2025   floor_less_eq_one          ~> floor_less_one
  2026   less_floor_eq_number_of    ~> number_of_less_floor
  2027   less_floor_eq_zero         ~> zero_less_floor
  2028   less_floor_eq_one          ~> one_less_floor
  2029   floor_le_eq_number_of      ~> floor_le_number_of
  2030   floor_le_eq_zero           ~> floor_le_zero
  2031   floor_le_eq_one            ~> floor_le_one
  2032   floor_subtract_number_of   ~> floor_diff_number_of
  2033   floor_subtract_one         ~> floor_diff_one
  2034   ceiling_number_of_eq       ~> ceiling_number_of
  2035   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  2036   ceiling_le_zero_eq         ~> ceiling_le_zero
  2037   ceiling_le_eq_one          ~> ceiling_le_one
  2038   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  2039   less_ceiling_eq_zero       ~> zero_less_ceiling
  2040   less_ceiling_eq_one        ~> one_less_ceiling
  2041   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  2042   ceiling_less_eq_zero       ~> ceiling_less_zero
  2043   ceiling_less_eq_one        ~> ceiling_less_one
  2044   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  2045   le_ceiling_eq_zero         ~> zero_le_ceiling
  2046   le_ceiling_eq_one          ~> one_le_ceiling
  2047   ceiling_subtract_number_of ~> ceiling_diff_number_of
  2048   ceiling_subtract_one       ~> ceiling_diff_one
  2049 
  2050 * Theory "Finite_Set": various folding_XXX locales facilitate the
  2051 application of the various fold combinators on finite sets.
  2052 
  2053 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  2054 provides abstract red-black tree type which is backed by "RBT_Impl" as
  2055 implementation.  INCOMPATIBILTY.
  2056 
  2057 * Theory Library/Coinductive_List has been removed -- superseded by
  2058 AFP/thys/Coinductive.
  2059 
  2060 * Theory PReal, including the type "preal" and related operations, has
  2061 been removed.  INCOMPATIBILITY.
  2062 
  2063 * Real: new development using Cauchy Sequences.
  2064 
  2065 * Split off theory "Big_Operators" containing setsum, setprod,
  2066 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  2067 
  2068 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  2069 "Int" etc.  INCOMPATIBILITY.
  2070 
  2071 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  2072 
  2073 * New set of rules "ac_simps" provides combined assoc / commute
  2074 rewrites for all interpretations of the appropriate generic locales.
  2075 
  2076 * Renamed theory "OrderedGroup" to "Groups" and split theory
  2077 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  2078 appropriate and more consistent names suitable for name prefixes
  2079 within the HOL theories.  INCOMPATIBILITY.
  2080 
  2081 * Some generic constants have been put to appropriate theories:
  2082   - less_eq, less: Orderings
  2083   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  2084   - inverse, divide: Rings
  2085 INCOMPATIBILITY.
  2086 
  2087 * More consistent naming of type classes involving orderings (and
  2088 lattices):
  2089 
  2090     lower_semilattice                   ~> semilattice_inf
  2091     upper_semilattice                   ~> semilattice_sup
  2092 
  2093     dense_linear_order                  ~> dense_linorder
  2094 
  2095     pordered_ab_group_add               ~> ordered_ab_group_add
  2096     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  2097     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  2098     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  2099     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  2100     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  2101     pordered_cancel_semiring            ~> ordered_cancel_semiring
  2102     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  2103     pordered_comm_ring                  ~> ordered_comm_ring
  2104     pordered_comm_semiring              ~> ordered_comm_semiring
  2105     pordered_ring                       ~> ordered_ring
  2106     pordered_ring_abs                   ~> ordered_ring_abs
  2107     pordered_semiring                   ~> ordered_semiring
  2108 
  2109     ordered_ab_group_add                ~> linordered_ab_group_add
  2110     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  2111     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  2112     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  2113     ordered_field                       ~> linordered_field
  2114     ordered_field_no_lb                 ~> linordered_field_no_lb
  2115     ordered_field_no_ub                 ~> linordered_field_no_ub
  2116     ordered_field_dense_linear_order    ~> dense_linordered_field
  2117     ordered_idom                        ~> linordered_idom
  2118     ordered_ring                        ~> linordered_ring
  2119     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  2120     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  2121     ordered_ring_strict                 ~> linordered_ring_strict
  2122     ordered_semidom                     ~> linordered_semidom
  2123     ordered_semiring                    ~> linordered_semiring
  2124     ordered_semiring_1                  ~> linordered_semiring_1
  2125     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  2126     ordered_semiring_strict             ~> linordered_semiring_strict
  2127 
  2128   The following slightly odd type classes have been moved to a
  2129   separate theory Library/Lattice_Algebras:
  2130 
  2131     lordered_ab_group_add               ~> lattice_ab_group_add
  2132     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  2133     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  2134     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  2135     lordered_ring                       ~> lattice_ring
  2136 
  2137 INCOMPATIBILITY.
  2138 
  2139 * Refined field classes:
  2140   - classes division_ring_inverse_zero, field_inverse_zero,
  2141     linordered_field_inverse_zero include rule inverse 0 = 0 --
  2142     subsumes former division_by_zero class;
  2143   - numerous lemmas have been ported from field to division_ring.
  2144 INCOMPATIBILITY.
  2145 
  2146 * Refined algebra theorem collections:
  2147   - dropped theorem group group_simps, use algebra_simps instead;
  2148   - dropped theorem group ring_simps, use field_simps instead;
  2149   - proper theorem collection field_simps subsumes former theorem
  2150     groups field_eq_simps and field_simps;
  2151   - dropped lemma eq_minus_self_iff which is a duplicate for
  2152     equal_neg_zero.
  2153 INCOMPATIBILITY.
  2154 
  2155 * Theory Finite_Set and List: some lemmas have been generalized from
  2156 sets to lattices:
  2157 
  2158   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  2159   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  2160   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  2161   union_Union_fold_union        ~> sup_Sup_fold_sup
  2162   Inter_fold_inter              ~> Inf_fold_inf
  2163   Union_fold_union              ~> Sup_fold_sup
  2164   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  2165   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  2166   INTER_fold_inter              ~> INFI_fold_inf
  2167   UNION_fold_union              ~> SUPR_fold_sup
  2168 
  2169 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  2170 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  2171 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  2172 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  2173 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  2174 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  2175 
  2176 * Reorganized theory Multiset: swapped notation of pointwise and
  2177 multiset order:
  2178 
  2179   - pointwise ordering is instance of class order with standard syntax
  2180     <= and <;
  2181   - multiset ordering has syntax <=# and <#; partial order properties
  2182     are provided by means of interpretation with prefix
  2183     multiset_order;
  2184   - less duplication, less historical organization of sections,
  2185     conversion from associations lists to multisets, rudimentary code
  2186     generation;
  2187   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  2188     if needed.
  2189 
  2190 Renamed:
  2191 
  2192   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  2193   multi_count_ext  ~>  multiset_ext
  2194   diff_union_inverse2  ~>  diff_union_cancelR
  2195 
  2196 INCOMPATIBILITY.
  2197 
  2198 * Theory Permutation: replaced local "remove" by List.remove1.
  2199 
  2200 * Code generation: ML and OCaml code is decorated with signatures.
  2201 
  2202 * Theory List: added transpose.
  2203 
  2204 * Library/Nat_Bijection.thy is a collection of bijective functions
  2205 between nat and other types, which supersedes the older libraries
  2206 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2207 
  2208   Constants:
  2209   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2210   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2211   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2212   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2213   Countable.pair_encode           ~> prod_encode
  2214   NatIso.prod2nat                 ~> prod_encode
  2215   NatIso.nat2prod                 ~> prod_decode
  2216   NatIso.sum2nat                  ~> sum_encode
  2217   NatIso.nat2sum                  ~> sum_decode
  2218   NatIso.list2nat                 ~> list_encode
  2219   NatIso.nat2list                 ~> list_decode
  2220   NatIso.set2nat                  ~> set_encode
  2221   NatIso.nat2set                  ~> set_decode
  2222 
  2223   Lemmas:
  2224   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2225   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2226   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2227   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2228   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2229   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2230   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2231   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2232   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2233   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2234   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2235   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2236   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2237 
  2238 * Sledgehammer:
  2239   - Renamed ATP commands:
  2240     atp_info     ~> sledgehammer running_atps
  2241     atp_kill     ~> sledgehammer kill_atps
  2242     atp_messages ~> sledgehammer messages
  2243     atp_minimize ~> sledgehammer minimize
  2244     print_atps   ~> sledgehammer available_atps
  2245     INCOMPATIBILITY.
  2246   - Added user's manual ("isabelle doc sledgehammer").
  2247   - Added option syntax and "sledgehammer_params" to customize
  2248     Sledgehammer's behavior.  See the manual for details.
  2249   - Modified the Isar proof reconstruction code so that it produces
  2250     direct proofs rather than proofs by contradiction.  (This feature
  2251     is still experimental.)
  2252   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2253     full-typed mode.
  2254   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2255 
  2256 * Nitpick:
  2257   - Added and implemented "binary_ints" and "bits" options.
  2258   - Added "std" option and implemented support for nonstandard models.
  2259   - Added and implemented "finitize" option to improve the precision
  2260     of infinite datatypes based on a monotonicity analysis.
  2261   - Added support for quotient types.
  2262   - Added support for "specification" and "ax_specification"
  2263     constructs.
  2264   - Added support for local definitions (for "function" and
  2265     "termination" proofs).
  2266   - Added support for term postprocessors.
  2267   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2268   - Improved efficiency of "destroy_constrs" optimization.
  2269   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2270     record getters.
  2271   - Fixed soundness bug related to higher-order constructors.
  2272   - Fixed soundness bug when "full_descrs" is enabled.
  2273   - Improved precision of set constructs.
  2274   - Added "atoms" option.
  2275   - Added cache to speed up repeated Kodkod invocations on the same
  2276     problems.
  2277   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2278     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2279     "SAT4J_Light".  INCOMPATIBILITY.
  2280   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2281     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2282   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2283 
  2284 * Method "induct" now takes instantiations of the form t, where t is not
  2285   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2286   If this is not intended, t has to be enclosed in parentheses.
  2287   By default, the equalities generated by definitional instantiations
  2288   are pre-simplified, which may cause parameters of inductive cases
  2289   to disappear, or may even delete some of the inductive cases.
  2290   Use "induct (no_simp)" instead of "induct" to restore the old
  2291   behaviour. The (no_simp) option is also understood by the "cases"
  2292   and "nominal_induct" methods, which now perform pre-simplification, too.
  2293   INCOMPATIBILITY.
  2294 
  2295 
  2296 *** HOLCF ***
  2297 
  2298 * Variable names in lemmas generated by the domain package have
  2299 changed; the naming scheme is now consistent with the HOL datatype
  2300 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2301 
  2302 * The domain package no longer defines the function "foo_copy" for
  2303 recursive domain "foo".  The reach lemma is now stated directly in
  2304 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2305 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2306 
  2307 * Most definedness lemmas generated by the domain package (previously
  2308 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2309 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2310 Proofs that used definedness lemmas as intro rules may break,
  2311 potential INCOMPATIBILITY.
  2312 
  2313 * Induction and casedist rules generated by the domain package now
  2314 declare proper case_names (one called "bottom", and one named for each
  2315 constructor).  INCOMPATIBILITY.
  2316 
  2317 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2318 rules are generated for each domain, INCOMPATIBILITY.
  2319 
  2320   foo_bar.reach       ~> foo.reach  bar.reach
  2321   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2322 
  2323 * Some lemmas generated by the domain package have been renamed for
  2324 consistency with the datatype package, INCOMPATIBILITY.
  2325 
  2326   foo.ind        ~> foo.induct
  2327   foo.finite_ind ~> foo.finite_induct
  2328   foo.coind      ~> foo.coinduct
  2329   foo.casedist   ~> foo.exhaust
  2330   foo.exhaust    ~> foo.nchotomy
  2331 
  2332 * For consistency with other definition packages, the fixrec package
  2333 now generates qualified theorem names, INCOMPATIBILITY.
  2334 
  2335   foo_simps  ~> foo.simps
  2336   foo_unfold ~> foo.unfold
  2337   foo_induct ~> foo.induct
  2338 
  2339 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2340 method and internal fixrec proofs now use the default simpset instead.
  2341 INCOMPATIBILITY.
  2342 
  2343 * The "contlub" predicate has been removed.  Proof scripts should use
  2344 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2345 
  2346 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2347 
  2348 * The constants cpair, cfst, and csnd have been removed in favor of
  2349 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2350 
  2351 
  2352 *** ML ***
  2353 
  2354 * Antiquotations for basic formal entities:
  2355 
  2356     @{class NAME}         -- type class
  2357     @{class_syntax NAME}  -- syntax representation of the above
  2358 
  2359     @{type_name NAME}     -- logical type
  2360     @{type_abbrev NAME}   -- type abbreviation
  2361     @{nonterminal NAME}   -- type of concrete syntactic category
  2362     @{type_syntax NAME}   -- syntax representation of any of the above
  2363 
  2364     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2365     @{const_abbrev NAME}  -- abbreviated constant
  2366     @{const_syntax NAME}  -- syntax representation of any of the above
  2367 
  2368 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2369 syntax constant (cf. 'syntax' command).
  2370 
  2371 * Antiquotation @{make_string} inlines a function to print arbitrary
  2372 values similar to the ML toplevel.  The result is compiler dependent
  2373 and may fall back on "?" in certain situations.
  2374 
  2375 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2376 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2377 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2378 not work with the asynchronous Isar document model.
  2379 
  2380 * Configuration options now admit dynamic default values, depending on
  2381 the context or even global references.
  2382 
  2383 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2384 uses an efficient external library if available (for Poly/ML).
  2385 
  2386 * Renamed some important ML structures, while keeping the old names
  2387 for some time as aliases within the structure Legacy:
  2388 
  2389   OuterKeyword  ~>  Keyword
  2390   OuterLex      ~>  Token
  2391   OuterParse    ~>  Parse
  2392   OuterSyntax   ~>  Outer_Syntax
  2393   PrintMode     ~>  Print_Mode
  2394   SpecParse     ~>  Parse_Spec
  2395   ThyInfo       ~>  Thy_Info
  2396   ThyLoad       ~>  Thy_Load
  2397   ThyOutput     ~>  Thy_Output
  2398   TypeInfer     ~>  Type_Infer
  2399 
  2400 Note that "open Legacy" simplifies porting of sources, but forgetting
  2401 to remove it again will complicate porting again in the future.
  2402 
  2403 * Most operations that refer to a global context are named
  2404 accordingly, e.g. Simplifier.global_context or
  2405 ProofContext.init_global.  There are some situations where a global
  2406 context actually works, but under normal circumstances one needs to
  2407 pass the proper local context through the code!
  2408 
  2409 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2410 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2411 Pretty.pp argument to merge, which is absent in the standard
  2412 Theory_Data version.
  2413 
  2414 * Sorts.certify_sort and derived "cert" operations for types and terms
  2415 no longer minimize sorts.  Thus certification at the boundary of the
  2416 inference kernel becomes invariant under addition of class relations,
  2417 which is an important monotonicity principle.  Sorts are now minimized
  2418 in the syntax layer only, at the boundary between the end-user and the
  2419 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2420 explicitly in rare situations.
  2421 
  2422 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2423 emphasize that this is in no way a standard operation.
  2424 INCOMPATIBILITY.
  2425 
  2426 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2427 usual for resolution.  Rare INCOMPATIBILITY.
  2428 
  2429 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2430 to emphasize that these only work in a global situation (which is
  2431 quite rare).
  2432 
  2433 * Curried take and drop in library.ML; negative length is interpreted
  2434 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2435 
  2436 * Proof terms: type substitutions on proof constants now use canonical
  2437 order of type variables.  INCOMPATIBILITY for tools working with proof
  2438 terms.
  2439 
  2440 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2441 may no longer carry premises.  User-level specifications are
  2442 transformed accordingly by Thm.add_axiom/add_def.
  2443 
  2444 
  2445 *** System ***
  2446 
  2447 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2448 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2449 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2450 
  2451 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2452 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2453 respectively.
  2454 
  2455 * Old lib/scripts/polyml-platform is superseded by the
  2456 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2457 variant, even on a 64 bit machine.  The following example setting
  2458 prefers 64 bit if available:
  2459 
  2460   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2461 
  2462 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2463 Isabelle/Scala layer for advanced prover interaction and integration.
  2464 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2465 component.
  2466 
  2467 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2468 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2469 similar to the default assignment of the document preparation system
  2470 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2471 provides some operations for direct access to the font without asking
  2472 the user for manual installation.
  2473 
  2474 
  2475 
  2476 New in Isabelle2009-1 (December 2009)
  2477 -------------------------------------
  2478 
  2479 *** General ***
  2480 
  2481 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2482 one backslash should be used, even in ML sources.
  2483 
  2484 
  2485 *** Pure ***
  2486 
  2487 * Locale interpretation propagates mixins along the locale hierarchy.
  2488 The currently only available mixins are the equations used to map
  2489 local definitions to terms of the target domain of an interpretation.
  2490 
  2491 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2492 loc" to print all interpretations of locale "loc" in the theory.
  2493 Interpretations in proofs are not shown.
  2494 
  2495 * Thoroughly revised locales tutorial.  New section on conditional
  2496 interpretation.
  2497 
  2498 * On instantiation of classes, remaining undefined class parameters
  2499 are formally declared.  INCOMPATIBILITY.
  2500 
  2501 
  2502 *** Document preparation ***
  2503 
  2504 * New generalized style concept for printing terms: @{foo (style) ...}
  2505 instead of @{foo_style style ...}  (old form is still retained for
  2506 backward compatibility).  Styles can be also applied for
  2507 antiquotations prop, term_type and typeof.
  2508 
  2509 
  2510 *** HOL ***
  2511 
  2512 * New proof method "smt" for a combination of first-order logic with
  2513 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2514 fixed-size bitvectors; there is also basic support for higher-order
  2515 features (esp. lambda abstractions).  It is an incomplete decision
  2516 procedure based on external SMT solvers using the oracle mechanism;
  2517 for the SMT solver Z3, this method is proof-producing.  Certificates
  2518 are provided to avoid calling the external solvers solely for
  2519 re-checking proofs.  Due to a remote SMT service there is no need for
  2520 installing SMT solvers locally.  See src/HOL/SMT.
  2521 
  2522 * New commands to load and prove verification conditions generated by
  2523 the Boogie program verifier or derived systems (e.g. the Verifying C
  2524 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2525 
  2526 * New counterexample generator tool 'nitpick' based on the Kodkod
  2527 relational model finder.  See src/HOL/Tools/Nitpick and
  2528 src/HOL/Nitpick_Examples.
  2529 
  2530 * New commands 'code_pred' and 'values' to invoke the predicate
  2531 compiler and to enumerate values of inductive predicates.
  2532 
  2533 * A tabled implementation of the reflexive transitive closure.
  2534 
  2535 * New implementation of quickcheck uses generic code generator;
  2536 default generators are provided for all suitable HOL types, records
  2537 and datatypes.  Old quickcheck can be re-activated importing theory
  2538 Library/SML_Quickcheck.
  2539 
  2540 * New testing tool Mirabelle for automated proof tools.  Applies
  2541 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2542 every proof step in a theory.  To be used in batch mode via the
  2543 "mirabelle" utility.
  2544 
  2545 * New proof method "sos" (sum of squares) for nonlinear real
  2546 arithmetic (originally due to John Harison). It requires theory
  2547 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2548 works well in practice on quantifier-free real arithmetic with +, -,
  2549 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2550 inequalities between polynomials.  It makes use of external
  2551 semidefinite programming solvers.  Method "sos" generates a
  2552 certificate that can be pasted into the proof thus avoiding the need
  2553 to call an external tool every time the proof is checked.  See
  2554 src/HOL/Library/Sum_Of_Squares.
  2555 
  2556 * New method "linarith" invokes existing linear arithmetic decision
  2557 procedure only.
  2558 
  2559 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2560 
  2561 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2562 Causes full type information to be output to the ATPs.  This slows
  2563 ATPs down considerably but eliminates a source of unsound "proofs"
  2564 that fail later.
  2565 
  2566 * New method "metisFT": A version of metis that uses full type
  2567 information in order to avoid failures of proof reconstruction.
  2568 
  2569 * New evaluator "approximate" approximates an real valued term using
  2570 the same method as the approximation method.
  2571 
  2572 * Method "approximate" now supports arithmetic expressions as
  2573 boundaries of intervals and implements interval splitting and Taylor
  2574 series expansion.
  2575 
  2576 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2577 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2578 
  2579 * New theory SupInf of the supremum and infimum operators for sets of
  2580 reals.
  2581 
  2582 * New theory Probability, which contains a development of measure
  2583 theory, eventually leading to Lebesgue integration and probability.
  2584 
  2585 * Extended Multivariate Analysis to include derivation and Brouwer's
  2586 fixpoint theorem.
  2587 
  2588 * Reorganization of number theory, INCOMPATIBILITY:
  2589   - new number theory development for nat and int, in theories Divides
  2590     and GCD as well as in new session Number_Theory
  2591   - some constants and facts now suffixed with _nat and _int
  2592     accordingly
  2593   - former session NumberTheory now named Old_Number_Theory, including
  2594     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2595   - moved theory Pocklington from src/HOL/Library to
  2596     src/HOL/Old_Number_Theory
  2597 
  2598 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2599 lcm of finite and infinite sets. It is shown that they form a complete
  2600 lattice.
  2601 
  2602 * Class semiring_div requires superclass no_zero_divisors and proof of
  2603 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2604 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2605 generalized to class semiring_div, subsuming former theorems
  2606 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2607 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2608 INCOMPATIBILITY.
  2609 
  2610 * Refinements to lattice classes and sets:
  2611   - less default intro/elim rules in locale variant, more default
  2612     intro/elim rules in class variant: more uniformity
  2613   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2614     le_inf_iff
  2615   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2616     sup_aci)
  2617   - renamed ACI to inf_sup_aci
  2618   - new class "boolean_algebra"
  2619   - class "complete_lattice" moved to separate theory
  2620     "Complete_Lattice"; corresponding constants (and abbreviations)
  2621     renamed and with authentic syntax:
  2622     Set.Inf ~>    Complete_Lattice.Inf
  2623     Set.Sup ~>    Complete_Lattice.Sup
  2624     Set.INFI ~>   Complete_Lattice.INFI
  2625     Set.SUPR ~>   Complete_Lattice.SUPR
  2626     Set.Inter ~>  Complete_Lattice.Inter
  2627     Set.Union ~>  Complete_Lattice.Union
  2628     Set.INTER ~>  Complete_Lattice.INTER
  2629     Set.UNION ~>  Complete_Lattice.UNION
  2630   - authentic syntax for
  2631     Set.Pow
  2632     Set.image
  2633   - mere abbreviations:
  2634     Set.empty               (for bot)
  2635     Set.UNIV                (for top)
  2636     Set.inter               (for inf, formerly Set.Int)
  2637     Set.union               (for sup, formerly Set.Un)
  2638     Complete_Lattice.Inter  (for Inf)
  2639     Complete_Lattice.Union  (for Sup)
  2640     Complete_Lattice.INTER  (for INFI)
  2641     Complete_Lattice.UNION  (for SUPR)
  2642   - object-logic definitions as far as appropriate
  2643 
  2644 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2645 Un_subset_iff are explicitly deleted as default simp rules; then also
  2646 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2647 deleted to achieve the desired effect.
  2648 
  2649 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2650 rules by default any longer; the same applies to min_max.inf_absorb1
  2651 etc.  INCOMPATIBILITY.
  2652 
  2653 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2654 pred_set_conv by default.  INCOMPATIBILITY.
  2655 
  2656 * Power operations on relations and functions are now one dedicated
  2657 constant "compow" with infix syntax "^^".  Power operation on
  2658 multiplicative monoids retains syntax "^" and is now defined generic
  2659 in class power.  INCOMPATIBILITY.
  2660 
  2661 * Relation composition "R O S" now has a more standard argument order:
  2662 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2663 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2664 break, since the O_assoc rule was not rewritten like this.  Fix using
  2665 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2666 
  2667 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2668 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2669 INCOMPATIBILITY.
  2670 
  2671 * Most rules produced by inductive and datatype package have mandatory
  2672 prefixes.  INCOMPATIBILITY.
  2673 
  2674 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2675 the attribute of the same name.  Each of the theorems in the list
  2676 DERIV_intros assumes composition with an additional function and
  2677 matches a variable to the derivative, which has to be solved by the
  2678 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2679 of most elementary terms.  Former Maclauren.DERIV_tac and
  2680 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2681 INCOMPATIBILITY.
  2682 
  2683 * Code generator attributes follow the usual underscore convention:
  2684     code_unfold     replaces    code unfold
  2685     code_post       replaces    code post
  2686     etc.
  2687   INCOMPATIBILITY.
  2688 
  2689 * Renamed methods:
  2690     sizechange -> size_change
  2691     induct_scheme -> induction_schema
  2692   INCOMPATIBILITY.
  2693 
  2694 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2695 INCOMPATIBILITY, use "undefined" directly.
  2696 
  2697 * Renamed theorems:
  2698     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2699     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2700     Suc_plus1 -> Suc_eq_plus1
  2701     *anti_sym -> *antisym*
  2702     vector_less_eq_def -> vector_le_def
  2703   INCOMPATIBILITY.
  2704 
  2705 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2706 INCOMPATIBILITY.
  2707 
  2708 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2709 INCOMPATIBILITY.
  2710 
  2711 
  2712 *** HOLCF ***
  2713 
  2714 * Theory Representable defines a class "rep" of domains that are
  2715 representable (via an ep-pair) in the universal domain type "udom".
  2716 Instances are provided for all type constructors defined in HOLCF.
  2717 
  2718 * The 'new_domain' command is a purely definitional version of the
  2719 domain package, for representable domains.  Syntax is identical to the
  2720 old domain package.  The 'new_domain' package also supports indirect
  2721 recursion using previously-defined type constructors.  See
  2722 src/HOLCF/ex/New_Domain.thy for examples.
  2723 
  2724 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2725 on the left-hand side of an equation, and then performs
  2726 simplification.  Rewriting is done using rules declared with the
  2727 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2728 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2729 
  2730 * The pattern-match compiler in 'fixrec' can now handle constructors
  2731 with HOL function types.  Pattern-match combinators for the Pair
  2732 constructor are pre-configured.
  2733 
  2734 * The 'fixrec' package now produces better fixed-point induction rules
  2735 for mutually-recursive definitions:  Induction rules have conclusions
  2736 of the form "P foo bar" instead of "P <foo, bar>".
  2737 
  2738 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2739 been renamed to "below".  The name "below" now replaces "less" in many
  2740 theorem names.  (Legacy theorem names using "less" are still supported
  2741 as well.)
  2742 
  2743 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2744 patterns can be used to generate strictness rules, or to make
  2745 functions more strict (much like the bang-patterns supported by the
  2746 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2747 examples.
  2748 
  2749 
  2750 *** ML ***
  2751 
  2752 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2753 errors and run-time exceptions, including detailed source positions.
  2754 
  2755 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2756 identified entries, with some additional information such as source
  2757 position, logical grouping etc.
  2758 
  2759 * Theory and context data is now introduced by the simplified and
  2760 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2761 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2762 copy operation) is still available for some time.
  2763 
  2764 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2765 provides a high-level programming interface to synchronized state
  2766 variables with atomic update.  This works via pure function
  2767 application within a critical section -- its runtime should be as
  2768 short as possible; beware of deadlocks if critical code is nested,
  2769 either directly or indirectly via other synchronized variables!
  2770 
  2771 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2772 wraps raw ML references, explicitly indicating their non-thread-safe
  2773 behaviour.  The Isar toplevel keeps this structure open, to
  2774 accommodate Proof General as well as quick and dirty interactive
  2775 experiments with references.
  2776 
  2777 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2778 parallel tactical reasoning.
  2779 
  2780 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2781 are similar to SUBPROOF, but are slightly more flexible: only the
  2782 specified parts of the subgoal are imported into the context, and the
  2783 body tactic may introduce new subgoals and schematic variables.
  2784 
  2785 * Old tactical METAHYPS, which does not observe the proof context, has
  2786 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2787 or Subgoal.FOCUS etc.
  2788 
  2789 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2790 functors have their own ML name space there is no point to mark them
  2791 separately.)  Minor INCOMPATIBILITY.
  2792 
  2793 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2794 
  2795 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2796 INCOMPATIBILITY.
  2797 
  2798 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2799 mode, which avoids critical setmp.
  2800 
  2801 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2802 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2803 Attrib/Method.setup introduced in Isabelle2009.
  2804 
  2805 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2806 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2807 last resort.  INCOMPATIBILITY.
  2808 
  2809 * Display.pretty_thm now requires a proper context (cf. former
  2810 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2811 or even Display.pretty_thm_without_context as last resort.
  2812 INCOMPATIBILITY.
  2813 
  2814 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2815 Syntax.pretty_typ/term directly, preferably with proper context
  2816 instead of global theory.
  2817 
  2818 
  2819 *** System ***
  2820 
  2821 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2822 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2823 usedir option -q.
  2824 
  2825 * Support for additional "Isabelle components" via etc/components, see
  2826 also the system manual.
  2827 
  2828 * The isabelle makeall tool now operates on all components with
  2829 IsaMakefile, not just hardwired "logics".
  2830 
  2831 * Removed "compress" option from isabelle-process and isabelle usedir;
  2832 this is always enabled.
  2833 
  2834 * Discontinued support for Poly/ML 4.x versions.
  2835 
  2836 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2837 on a given logic image.  This requires the lighttpd webserver and is
  2838 currently supported on Linux only.
  2839 
  2840 
  2841 
  2842 New in Isabelle2009 (April 2009)
  2843 --------------------------------
  2844 
  2845 *** General ***
  2846 
  2847 * Simplified main Isabelle executables, with less surprises on
  2848 case-insensitive file-systems (such as Mac OS).
  2849 
  2850   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2851     "isatool."
  2852 
  2853   - The former "isabelle" alias for "isabelle-process" has been
  2854     removed (should rarely occur to regular users).
  2855 
  2856   - The former "isabelle-interface" and its alias "Isabelle" have been
  2857     removed (interfaces are now regular Isabelle tools).
  2858 
  2859 Within scripts and make files, the Isabelle environment variables
  2860 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2861 respectively.  (The latter are still available as legacy feature.)
  2862 
  2863 The old isabelle-interface wrapper could react in confusing ways if
  2864 the interface was uninstalled or changed otherwise.  Individual
  2865 interface tool configuration is now more explicit, see also the
  2866 Isabelle system manual.  In particular, Proof General is now available
  2867 via "isabelle emacs".
  2868 
  2869 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2870 purge installed copies of Isabelle executables and re-run "isabelle
  2871 install -p ...", or use symlinks.
  2872 
  2873 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2874 old ~/isabelle, which was slightly non-standard and apt to cause
  2875 surprises on case-insensitive file-systems (such as Mac OS).
  2876 
  2877 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2878 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2879 care is required when using older releases of Isabelle.  Note that
  2880 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2881 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2882 
  2883 * Proofs of fully specified statements are run in parallel on
  2884 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2885 a regular 4-core machine, if the initial heap space is made reasonably
  2886 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2887 
  2888 * The main reference manuals ("isar-ref", "implementation", and
  2889 "system") have been updated and extended.  Formally checked references
  2890 as hyperlinks are now available uniformly.
  2891 
  2892 
  2893 *** Pure ***
  2894 
  2895 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2896 respects.  The most important changes are listed below.  See the
  2897 Tutorial on Locales ("locales" manual) for details.
  2898 
  2899 - In locale expressions, instantiation replaces renaming.  Parameters
  2900 must be declared in a for clause.  To aid compatibility with previous
  2901 parameter inheritance, in locale declarations, parameters that are not
  2902 'touched' (instantiation position "_" or omitted) are implicitly added
  2903 with their syntax at the beginning of the for clause.
  2904 
  2905 - Syntax from abbreviations and definitions in locales is available in
  2906 locale expressions and context elements.  The latter is particularly
  2907 useful in locale declarations.
  2908 
  2909 - More flexible mechanisms to qualify names generated by locale
  2910 expressions.  Qualifiers (prefixes) may be specified in locale
  2911 expressions, and can be marked as mandatory (syntax: "name!:") or
  2912 optional (syntax "name?:").  The default depends for plain "name:"
  2913 depends on the situation where a locale expression is used: in
  2914 commands 'locale' and 'sublocale' prefixes are optional, in
  2915 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2916 implicit qualifiers derived from the parameter names of a locale are
  2917 no longer generated.
  2918 
  2919 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2920 instantiation clause in "interpretation" and "interpret" (square
  2921 brackets) is no longer available.  Use locale expressions.
  2922 
  2923 - When converting proof scripts, mandatory qualifiers in
  2924 'interpretation' and 'interpret' should be retained by default, even
  2925 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2926 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2927 in locale expressions range over a single locale instance only.
  2928 
  2929 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2930 In existing theorem specifications replace the includes element by the
  2931 respective context elements of the included locale, omitting those
  2932 that are already present in the theorem specification.  Multiple
  2933 assume elements of a locale should be replaced by a single one
  2934 involving the locale predicate.  In the proof body, declarations (most
  2935 notably theorems) may be regained by interpreting the respective
  2936 locales in the proof context as required (command "interpret").
  2937 
  2938 If using "includes" in replacement of a target solely because the
  2939 parameter types in the theorem are not as general as in the target,
  2940 consider declaring a new locale with additional type constraints on
  2941 the parameters (context element "constrains").
  2942 
  2943 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2944 
  2945 - Locale interpretation commands no longer attempt to simplify goal.
  2946 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2947 methods intro_locales and unfold_locales to clarify.
  2948 
  2949 - Locale interpretation commands no longer accept interpretation
  2950 attributes.  INCOMPATIBILITY.
  2951 
  2952 * Class declaration: so-called "base sort" must not be given in import
  2953 list any longer, but is inferred from the specification.  Particularly
  2954 in HOL, write
  2955 
  2956     class foo = ...
  2957 
  2958 instead of
  2959 
  2960     class foo = type + ...
  2961 
  2962 * Class target: global versions of theorems stemming do not carry a
  2963 parameter prefix any longer.  INCOMPATIBILITY.
  2964 
  2965 * Class 'instance' command no longer accepts attached definitions.
  2966 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2967 
  2968 * Recovered hiding of consts, which was accidentally broken in
  2969 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2970 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2971 
  2972 * Slightly more coherent Pure syntax, with updated documentation in
  2973 isar-ref manual.  Removed locales meta_term_syntax and
  2974 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2975 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2976 directly in regular applications.
  2977 
  2978 * There is a new syntactic category "float_const" for signed decimal
  2979 fractions (e.g. 123.45 or -123.45).
  2980 
  2981 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2982 interface with 'setup' command instead.
  2983 
  2984 * Command 'local_setup' is similar to 'setup', but operates on a local
  2985 theory context.
  2986 
  2987 * The 'axiomatization' command now only works within a global theory
  2988 context.  INCOMPATIBILITY.
  2989 
  2990 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2991 hypotheses.  Sorts required in the course of reasoning need to be
  2992 covered by the constraints in the initial statement, completed by the
  2993 type instance information of the background theory.  Non-trivial sort
  2994 hypotheses, which rarely occur in practice, may be specified via
  2995 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2996 
  2997   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2998 
  2999 The result contains an implicit sort hypotheses as before --
  3000 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  3001 normalization.
  3002 
  3003 * Generalized Isar history, with support for linear undo, direct state
  3004 addressing etc.
  3005 
  3006 * Changed defaults for unify configuration options:
  3007 
  3008   unify_trace_bound = 50 (formerly 25)
  3009   unify_search_bound = 60 (formerly 30)
  3010 
  3011 * Different bookkeeping for code equations (INCOMPATIBILITY):
  3012 
  3013   a) On theory merge, the last set of code equations for a particular
  3014      constant is taken (in accordance with the policy applied by other
  3015      parts of the code generator framework).
  3016 
  3017   b) Code equations stemming from explicit declarations (e.g. code
  3018      attribute) gain priority over default code equations stemming
  3019      from definition, primrec, fun etc.
  3020 
  3021 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  3022 
  3023 * Unified theorem tables for both code generators.  Thus [code
  3024 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  3025 
  3026 * Command 'find_consts' searches for constants based on type and name
  3027 patterns, e.g.
  3028 
  3029     find_consts "_ => bool"
  3030 
  3031 By default, matching is against subtypes, but it may be restricted to
  3032 the whole type.  Searching by name is possible.  Multiple queries are
  3033 conjunctive and queries may be negated by prefixing them with a
  3034 hyphen:
  3035 
  3036     find_consts strict: "_ => bool" name: "Int" -"int => int"
  3037 
  3038 * New 'find_theorems' criterion "solves" matches theorems that
  3039 directly solve the current goal (modulo higher-order unification).
  3040 
  3041 * Auto solve feature for main theorem statements: whenever a new goal
  3042 is stated, "find_theorems solves" is called; any theorems that could
  3043 solve the lemma directly are listed as part of the goal state.
  3044 Cf. associated options in Proof General Isabelle settings menu,
  3045 enabled by default, with reasonable timeout for pathological cases of
  3046 higher-order unification.
  3047 
  3048 
  3049 *** Document preparation ***
  3050 
  3051 * Antiquotation @{lemma} now imitates a regular terminal proof,
  3052 demanding keyword 'by' and supporting the full method expression
  3053 syntax just like the Isar command 'by'.
  3054 
  3055 
  3056 *** HOL ***
  3057 
  3058 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  3059 points Main and Complex_Main remain as before.
  3060 
  3061 * Logic image HOL-Plain provides a minimal HOL with the most important
  3062 tools available (inductive, datatype, primrec, ...).  This facilitates
  3063 experimentation and tool development.  Note that user applications
  3064 (and library theories) should never refer to anything below theory
  3065 Main, as before.
  3066 
  3067 * Logic image HOL-Main stops at theory Main, and thus facilitates
  3068 experimentation due to shorter build times.
  3069 
  3070 * Logic image HOL-NSA contains theories of nonstandard analysis which
  3071 were previously part of former HOL-Complex.  Entry point Hyperreal
  3072 remains valid, but theories formerly using Complex_Main should now use
  3073 new entry point Hypercomplex.
  3074 
  3075 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  3076 Posix processes.  Avoids potentially expensive forking of the ML
  3077 process.  New thread-based implementation also works on non-Unix
  3078 platforms (Cygwin).  Provers are no longer hardwired, but defined
  3079 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  3080 commands are covered in the isar-ref manual.
  3081 
  3082 * Wrapper scripts for remote SystemOnTPTP service allows to use
  3083 sledgehammer without local ATP installation (Vampire etc.). Other
  3084 provers may be included via suitable ML wrappers, see also
  3085 src/HOL/ATP_Linkup.thy.
  3086 
  3087 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  3088 menu.
  3089 
  3090 * The metis method no longer fails because the theorem is too trivial
  3091 (contains the empty clause).
  3092 
  3093 * The metis method now fails in the usual manner, rather than raising
  3094 an exception, if it determines that it cannot prove the theorem.
  3095 
  3096 * Method "coherent" implements a prover for coherent logic (see also
  3097 src/Tools/coherent.ML).
  3098 
  3099 * Constants "undefined" and "default" replace "arbitrary".  Usually
  3100 "undefined" is the right choice to replace "arbitrary", though
  3101 logically there is no difference.  INCOMPATIBILITY.
  3102 
  3103 * Command "value" now integrates different evaluation mechanisms.  The
  3104 result of the first successful evaluation mechanism is printed.  In
  3105 square brackets a particular named evaluation mechanisms may be
  3106 specified (currently, [SML], [code] or [nbe]).  See further
  3107 src/HOL/ex/Eval_Examples.thy.
  3108 
  3109 * Normalization by evaluation now allows non-leftlinear equations.
  3110 Declare with attribute [code nbe].
  3111 
  3112 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  3113 as the structured Isar versions "cases" and "induct", cf. the
  3114 corresponding "cases" and "induct" attributes.  Mutual induction rules
  3115 are now presented as a list of individual projections
  3116 (e.g. foo_bar.inducts for types foo and bar); the old format with
  3117 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  3118 rare situations a different rule is selected --- notably nested tuple
  3119 elimination instead of former prod.exhaust: use explicit (case_tac t
  3120 rule: prod.exhaust) here.
  3121 
  3122 * Attributes "cases", "induct", "coinduct" support "del" option.
  3123 
  3124 * Removed fact "case_split_thm", which duplicates "case_split".
  3125 
  3126 * The option datatype has been moved to a new theory Option.  Renamed
  3127 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  3128 
  3129 * New predicate "strict_mono" classifies strict functions on partial
  3130 orders.  With strict functions on linear orders, reasoning about
  3131 (in)equalities is facilitated by theorems "strict_mono_eq",
  3132 "strict_mono_less_eq" and "strict_mono_less".
  3133 
  3134 * Some set operations are now proper qualified constants with
  3135 authentic syntax.  INCOMPATIBILITY:
  3136 
  3137     op Int ~>   Set.Int
  3138     op Un ~>    Set.Un
  3139     INTER ~>    Set.INTER
  3140     UNION ~>    Set.UNION
  3141     Inter ~>    Set.Inter
  3142     Union ~>    Set.Union
  3143     {} ~>       Set.empty
  3144     UNIV ~>     Set.UNIV
  3145 
  3146 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  3147 theory Set.
  3148 
  3149 * Auxiliary class "itself" has disappeared -- classes without any
  3150 parameter are treated as expected by the 'class' command.
  3151 
  3152 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  3153 
  3154 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  3155 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  3156 
  3157 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  3158 method "approximation".  It proves formulas on real values by using
  3159 interval arithmetic.  In the formulas are also the transcendental
  3160 functions sin, cos, tan, atan, ln, exp and the constant pi are
  3161 allowed. For examples see
  3162 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  3163 
  3164 * Theory "Reflection" now resides in HOL/Library.
  3165 
  3166 * Entry point to Word library now simply named "Word".
  3167 INCOMPATIBILITY.
  3168 
  3169 * Made source layout more coherent with logical distribution
  3170 structure:
  3171 
  3172     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  3173     src/HOL/Library/Code_Message.thy ~> src/HOL/
  3174     src/HOL/Library/GCD.thy ~> src/HOL/
  3175     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  3176     src/HOL/Library/Parity.thy ~> src/HOL/
  3177     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  3178     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  3179     src/HOL/Real/Lubs.thy ~> src/HOL/
  3180     src/HOL/Real/PReal.thy ~> src/HOL/
  3181     src/HOL/Real/Rational.thy ~> src/HOL/
  3182     src/HOL/Real/RComplete.thy ~> src/HOL/
  3183     src/HOL/Real/RealDef.thy ~> src/HOL/
  3184     src/HOL/Real/RealPow.thy ~> src/HOL/
  3185     src/HOL/Real/Real.thy ~> src/HOL/
  3186     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  3187     src/HOL/Complex/Complex.thy ~> src/HOL/
  3188     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  3189     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  3190     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  3191     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  3192     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  3193     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  3194     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  3195     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  3196     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  3197     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  3198     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  3199     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  3200     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  3201     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  3202     src/HOL/Real/Float ~> src/HOL/Library/
  3203     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  3204     src/HOL/Real/RealVector.thy ~> src/HOL/
  3205 
  3206     src/HOL/arith_data.ML ~> src/HOL/Tools
  3207     src/HOL/hologic.ML ~> src/HOL/Tools
  3208     src/HOL/simpdata.ML ~> src/HOL/Tools
  3209     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3210     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3211     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3212     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3213     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3214     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3215     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3216 
  3217     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3218     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3219     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3220     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3221     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3222     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3223 
  3224 * If methods "eval" and "evaluation" encounter a structured proof
  3225 state with !!/==>, only the conclusion is evaluated to True (if
  3226 possible), avoiding strange error messages.
  3227 
  3228 * Method "sizechange" automates termination proofs using (a
  3229 modification of) the size-change principle.  Requires SAT solver.  See
  3230 src/HOL/ex/Termination.thy for examples.
  3231 
  3232 * Simplifier: simproc for let expressions now unfolds if bound
  3233 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3234 
  3235 * Method "arith": Linear arithmetic now ignores all inequalities when
  3236 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3237 
  3238 * New attribute "arith" for facts that should always be used
  3239 automatically by arithmetic. It is intended to be used locally in
  3240 proofs, e.g.
  3241 
  3242   assumes [arith]: "x > 0"
  3243 
  3244 Global usage is discouraged because of possible performance impact.
  3245 
  3246 * New classes "top" and "bot" with corresponding operations "top" and
  3247 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3248 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3249 
  3250 * Changed definition lemma "less_fun_def" in order to provide an
  3251 instance for preorders on functions; use lemma "less_le" instead.
  3252 INCOMPATIBILITY.
  3253 
  3254 * Theory Orderings: class "wellorder" moved here, with explicit
  3255 induction rule "less_induct" as assumption.  For instantiation of
  3256 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3257 INCOMPATIBILITY.
  3258 
  3259 * Theory Orderings: added class "preorder" as superclass of "order".
  3260 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3261 etc. slightly changed.  Some theorems named order_class.* now named
  3262 preorder_class.*.
  3263 
  3264 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3265 "diag" to "Id_on".
  3266 
  3267 * Theory Finite_Set: added a new fold combinator of type
  3268 
  3269   ('a => 'b => 'b) => 'b => 'a set => 'b
  3270 
  3271 Occasionally this is more convenient than the old fold combinator
  3272 which is now defined in terms of the new one and renamed to
  3273 fold_image.
  3274 
  3275 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3276 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3277 extended with further lemmas!).  At the moment both still exist but
  3278 the former will disappear at some point.
  3279 
  3280 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3281 class recpower.  Type-specific simp rules for various recpower types
  3282 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3283 
  3284 rat_power_0    -> power_0
  3285 rat_power_Suc  -> power_Suc
  3286 realpow_0      -> power_0
  3287 realpow_Suc    -> power_Suc
  3288 complexpow_0   -> power_0
  3289 complexpow_Suc -> power_Suc
  3290 power_poly_0   -> power_0
  3291 power_poly_Suc -> power_Suc
  3292 
  3293 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3294 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3295 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3296 of lemmas from Divides has been generalized from nat to class
  3297 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3298 renames resulting from duplicate elimination:
  3299 
  3300     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3301     zero_dvd_iff ~>         dvd_0_left_iff
  3302     dvd_0 ~>                dvd_0_right
  3303     DIVISION_BY_ZERO_DIV ~> div_by_0
  3304     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3305     mult_div ~>             div_mult_self2_is_id
  3306     mult_mod ~>             mod_mult_self2_is_0
  3307 
  3308 * Theory IntDiv: removed many lemmas that are instances of class-based
  3309 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3310 rename old lemmas as follows:
  3311 
  3312 dvd_diff               -> nat_dvd_diff
  3313 dvd_zminus_iff         -> dvd_minus_iff
  3314 mod_add1_eq            -> mod_add_eq
  3315 mod_mult1_eq           -> mod_mult_right_eq
  3316 mod_mult1_eq'          -> mod_mult_left_eq
  3317 mod_mult_distrib_mod   -> mod_mult_eq
  3318 nat_mod_add_left_eq    -> mod_add_left_eq
  3319 nat_mod_add_right_eq   -> mod_add_right_eq
  3320 nat_mod_div_trivial    -> mod_div_trivial
  3321 nat_mod_mod_trivial    -> mod_mod_trivial
  3322 zdiv_zadd_self1        -> div_add_self1
  3323 zdiv_zadd_self2        -> div_add_self2
  3324 zdiv_zmult_self1       -> div_mult_self2_is_id
  3325 zdiv_zmult_self2       -> div_mult_self1_is_id
  3326 zdvd_triv_left         -> dvd_triv_left
  3327 zdvd_triv_right        -> dvd_triv_right
  3328 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3329 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3330 zmod_zadd_left_eq      -> mod_add_left_eq
  3331 zmod_zadd_right_eq     -> mod_add_right_eq
  3332 zmod_zadd_self1        -> mod_add_self1
  3333 zmod_zadd_self2        -> mod_add_self2
  3334 zmod_zadd1_eq          -> mod_add_eq
  3335 zmod_zdiff1_eq         -> mod_diff_eq
  3336 zmod_zdvd_zmod         -> mod_mod_cancel
  3337 zmod_zmod_cancel       -> mod_mod_cancel
  3338 zmod_zmult_self1       -> mod_mult_self2_is_0
  3339 zmod_zmult_self2       -> mod_mult_self1_is_0
  3340 zmod_1                 -> mod_by_1
  3341 zdiv_1                 -> div_by_1
  3342 zdvd_abs1              -> abs_dvd_iff
  3343 zdvd_abs2              -> dvd_abs_iff
  3344 zdvd_refl              -> dvd_refl
  3345 zdvd_trans             -> dvd_trans
  3346 zdvd_zadd              -> dvd_add
  3347 zdvd_zdiff             -> dvd_diff
  3348 zdvd_zminus_iff        -> dvd_minus_iff
  3349 zdvd_zminus2_iff       -> minus_dvd_iff
  3350 zdvd_zmultD            -> dvd_mult_right
  3351 zdvd_zmultD2           -> dvd_mult_left
  3352 zdvd_zmult_mono        -> mult_dvd_mono
  3353 zdvd_0_right           -> dvd_0_right
  3354 zdvd_0_left            -> dvd_0_left_iff
  3355 zdvd_1_left            -> one_dvd
  3356 zminus_dvd_iff         -> minus_dvd_iff
  3357 
  3358 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3359 
  3360 * The real numbers offer decimal input syntax: 12.34 is translated
  3361 into 1234/10^2. This translation is not reversed upon output.
  3362 
  3363 * Theory Library/Polynomial defines an abstract type 'a poly of
  3364 univariate polynomials with coefficients of type 'a.  In addition to
  3365 the standard ring operations, it also supports div and mod.  Code
  3366 generation is also supported, using list-style constructors.
  3367 
  3368 * Theory Library/Inner_Product defines a class of real_inner for real
  3369 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3370 => real.  Class real_inner is a subclass of real_normed_vector from
  3371 theory RealVector.
  3372 
  3373 * Theory Library/Product_Vector provides instances for the product
  3374 type 'a * 'b of several classes from RealVector and Inner_Product.
  3375 Definitions of addition, subtraction, scalar multiplication, norms,
  3376 and inner products are included.
  3377 
  3378 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3379 addition to the field operations, numerals and case syntax are also
  3380 supported.
  3381 
  3382 * Theory Library/Diagonalize provides constructive version of Cantor's
  3383 first diagonalization argument.
  3384 
  3385 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3386 zlcm (for int); carried together from various gcd/lcm developements in
  3387 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3388 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3389 may recover tupled syntax as follows:
  3390 
  3391     hide (open) const gcd
  3392     abbreviation gcd where
  3393       "gcd == (%(a, b). GCD.gcd a b)"
  3394     notation (output)
  3395       GCD.gcd ("gcd '(_, _')")
  3396 
  3397 The same works for lcm, zgcd, zlcm.
  3398 
  3399 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3400 instantiations for algebraic structures.  Removed some duplicate
  3401 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3402 
  3403 * ML antiquotation @{code} takes a constant as argument and generates
  3404 corresponding code in background and inserts name of the corresponding
  3405 resulting ML value/function/datatype constructor binding in place.
  3406 All occurrences of @{code} with a single ML block are generated
  3407 simultaneously.  Provides a generic and safe interface for
  3408 instrumentalizing code generation.  See
  3409 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3410 In future you ought to refrain from ad-hoc compiling generated SML
  3411 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3412 cannot refer to constants for which user-defined serializations are
  3413 set.  Refer to the corresponding ML counterpart directly in that
  3414 cases.
  3415 
  3416 * Command 'rep_datatype': instead of theorem names the command now
  3417 takes a list of terms denoting the constructors of the type to be
  3418 represented as datatype.  The characteristic theorems have to be
  3419 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3420 have disappeared in favour of existing ones:
  3421 
  3422     unit_induct                 ~> unit.induct
  3423     prod_induct                 ~> prod.induct
  3424     sum_induct                  ~> sum.induct
  3425     Suc_Suc_eq                  ~> nat.inject
  3426     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3427 
  3428 
  3429 *** HOL-Algebra ***
  3430 
  3431 * New locales for orders and lattices where the equivalence relation
  3432 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3433 locales use a record structure with field eq for the equivalence.
  3434 
  3435 * New theory of factorial domains.
  3436 
  3437 * Units_l_inv and Units_r_inv are now simp rules by default.
  3438 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3439 and/or r_inv will now also require deletion of these lemmas.
  3440 
  3441 * Renamed the following theorems, INCOMPATIBILITY:
  3442 
  3443 UpperD ~> Upper_memD
  3444 LowerD ~> Lower_memD
  3445 least_carrier ~> least_closed
  3446 greatest_carrier ~> greatest_closed
  3447 greatest_Lower_above ~> greatest_Lower_below
  3448 one_zero ~> carrier_one_zero
  3449 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3450 
  3451 
  3452 *** HOL-Nominal ***
  3453 
  3454 * Nominal datatypes can now contain type-variables.
  3455 
  3456 * Commands 'nominal_inductive' and 'equivariance' work with local
  3457 theory targets.
  3458 
  3459 * Nominal primrec can now works with local theory targets and its
  3460 specification syntax now conforms to the general format as seen in
  3461 'inductive' etc.
  3462 
  3463 * Method "perm_simp" honours the standard simplifier attributes
  3464 (no_asm), (no_asm_use) etc.
  3465 
  3466 * The new predicate #* is defined like freshness, except that on the
  3467 left hand side can be a set or list of atoms.
  3468 
  3469 * Experimental command 'nominal_inductive2' derives strong induction
  3470 principles for inductive definitions.  In contrast to
  3471 'nominal_inductive', which can only deal with a fixed number of
  3472 binders, it can deal with arbitrary expressions standing for sets of
  3473 atoms to be avoided.  The only inductive definition we have at the
  3474 moment that needs this generalisation is the typing rule for Lets in
  3475 the algorithm W:
  3476 
  3477  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3478  -----------------------------------------------------------------
  3479          Gamma |- Let x be t1 in t2 : T2
  3480 
  3481 In this rule one wants to avoid all the binders that are introduced by
  3482 "close Gamma T1".  We are looking for other examples where this
  3483 feature might be useful.  Please let us know.
  3484 
  3485 
  3486 *** HOLCF ***
  3487 
  3488 * Reimplemented the simplification procedure for proving continuity
  3489 subgoals.  The new simproc is extensible; users can declare additional
  3490 continuity introduction rules with the attribute [cont2cont].
  3491 
  3492 * The continuity simproc now uses a different introduction rule for
  3493 solving continuity subgoals on terms with lambda abstractions.  In
  3494 some rare cases the new simproc may fail to solve subgoals that the
  3495 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3496 Potential INCOMPATIBILITY.
  3497 
  3498 * Command 'fixrec': specification syntax now conforms to the general
  3499 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3500 examples.  INCOMPATIBILITY.
  3501 
  3502 
  3503 *** ZF ***
  3504 
  3505 * Proof of Zorn's Lemma for partial orders.
  3506 
  3507 
  3508 *** ML ***
  3509 
  3510 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3511 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3512 depends on multithreading, so timouts will not work before Poly/ML
  3513 5.2.1!
  3514 
  3515 * High-level support for concurrent ML programming, see
  3516 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3517 particularly convenient to organize independent functional
  3518 computations.  The concept of "synchronized variables" provides a
  3519 higher-order interface for components with shared state, avoiding the
  3520 delicate details of mutexes and condition variables.  (Requires
  3521 Poly/ML 5.2.1 or later.)
  3522 
  3523 * ML bindings produced via Isar commands are stored within the Isar
  3524 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3525 become thread-safe and work with undo as expected (concerning
  3526 top-level bindings, not side-effects on global references).
  3527 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3528 compiler at runtime; really global bindings need to be given outside a
  3529 theory.  (Requires Poly/ML 5.2 or later.)
  3530 
  3531 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3532 context.  Top-level ML bindings are stored within the proof context in
  3533 a purely sequential fashion, disregarding the nested proof structure.
  3534 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3535 proof.  (Requires Poly/ML 5.2 or later.)
  3536 
  3537 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3538 and Method.setup, as well as Isar commands 'attribute_setup' and
  3539 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3540 existing code accordingly, or use plain 'setup' together with old
  3541 Method.add_method.
  3542 
  3543 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3544 to 'a -> thm, while results are always tagged with an authentic oracle
  3545 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3546 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3547 accordingly.  Note that extra performance may be gained by producing
  3548 the cterm carefully, avoiding slow Thm.cterm_of.
  3549 
  3550 * Simplified interface for defining document antiquotations via
  3551 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3552 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3553 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3554 examples.
  3555 
  3556 * More systematic treatment of long names, abstract name bindings, and
  3557 name space operations.  Basic operations on qualified names have been
  3558 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3559 Long_Name.append.  Old type bstring has been mostly replaced by
  3560 abstract type binding (see structure Binding), which supports precise
  3561 qualification by packages and local theory targets, as well as proper
  3562 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3563 bstring values into Binding.name, or better pass through abstract
  3564 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3565 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3566 
  3567 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3568 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3569 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3570 
  3571 * Disposed old type and term read functions (Sign.read_def_typ,
  3572 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3573 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3574 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3575 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3576 resort for legacy applications.
  3577 
  3578 * Disposed old declarations, tactics, tactic combinators that refer to
  3579 the simpset or claset of an implicit theory (such as Addsimps,
  3580 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3581 embedded ML text, or local_simpset_of with a proper context passed as
  3582 explicit runtime argument.
  3583 
  3584 * Rules and tactics that read instantiations (read_instantiate,
  3585 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3586 context, which is required for parsing and type-checking.  Moreover,
  3587 the variables are specified as plain indexnames, not string encodings
  3588 thereof.  INCOMPATIBILITY.
  3589 
  3590 * Generic Toplevel.add_hook interface allows to analyze the result of
  3591 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3592 for theorem dependency output of transactions resulting in a new
  3593 theory state.
  3594 
  3595 * ML antiquotations: block-structured compilation context indicated by
  3596 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3597 
  3598   @{binding name}                         - basic name binding
  3599   @{let ?pat = term}                      - term abbreviation (HO matching)
  3600   @{note name = fact}                     - fact abbreviation
  3601   @{thm fact}                             - singleton fact (with attributes)
  3602   @{thms fact}                            - general fact (with attributes)
  3603   @{lemma prop by method}                 - singleton goal
  3604   @{lemma prop by meth1 meth2}            - singleton goal
  3605   @{lemma prop1 ... propN by method}      - general goal
  3606   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3607   @{lemma (open) ...}                     - open derivation
  3608 
  3609 
  3610 *** System ***
  3611 
  3612 * The Isabelle "emacs" tool provides a specific interface to invoke
  3613 Proof General / Emacs, with more explicit failure if that is not
  3614 installed (the old isabelle-interface script silently falls back on
  3615 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3616 installation location of the Proof General distribution.
  3617 
  3618 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3619 the Isabelle process into a JVM/Scala application.  See
  3620 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3621 process wrapper has been discontinued.)
  3622 
  3623 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3624 
  3625 * Various status messages (with exact source position information) are
  3626 emitted, if proper markup print mode is enabled.  This allows
  3627 user-interface components to provide detailed feedback on internal
  3628 prover operations.
  3629 
  3630 
  3631 
  3632 New in Isabelle2008 (June 2008)
  3633 -------------------------------
  3634 
  3635 *** General ***
  3636 
  3637 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3638 and updated, with formally checked references as hyperlinks.
  3639 
  3640 * Theory loader: use_thy (and similar operations) no longer set the
  3641 implicit ML context, which was occasionally hard to predict and in
  3642 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3643 provides a proper context already.
  3644 
  3645 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3646 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3647 'use' within a theory file will do the job.
  3648 
  3649 * Name space merge now observes canonical order, i.e. the second space
  3650 is inserted into the first one, while existing entries in the first
  3651 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3652 swap theory imports.
  3653 
  3654 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3655 INCOMPATIBILITY in identifier syntax etc.
  3656 
  3657 * Outer syntax: string tokens no longer admit escaped white space,
  3658 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3659 white space without escapes.
  3660 
  3661 * Outer syntax: string tokens may contain arbitrary character codes
  3662 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3663 "foo_bar".
  3664 
  3665 
  3666 *** Pure ***
  3667 
  3668 * Context-dependent token translations.  Default setup reverts locally
  3669 fixed variables, and adds hilite markup for undeclared frees.
  3670 
  3671 * Unused theorems can be found using the new command 'unused_thms'.
  3672 There are three ways of invoking it:
  3673 
  3674 (1) unused_thms
  3675      Only finds unused theorems in the current theory.
  3676 
  3677 (2) unused_thms thy_1 ... thy_n -
  3678      Finds unused theorems in the current theory and all of its ancestors,
  3679      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3680 
  3681 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3682      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3683      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3684      their ancestors.
  3685 
  3686 In order to increase the readability of the list produced by
  3687 unused_thms, theorems that have been created by a particular instance
  3688 of a theory command such as 'inductive' or 'function' are considered
  3689 to belong to the same "group", meaning that if at least one theorem in
  3690 this group is used, the other theorems in the same group are no longer
  3691 reported as unused.  Moreover, if all theorems in the group are
  3692 unused, only one theorem in the group is displayed.
  3693 
  3694 Note that proof objects have to be switched on in order for
  3695 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3696 usually the case when using Proof General with the default settings).
  3697 
  3698 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3699 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3700 duplicate fact bindings, or even accidental fact duplications.  Note
  3701 that tools may maintain dynamically scoped facts systematically, using
  3702 PureThy.add_thms_dynamic.
  3703 
  3704 * Command 'hide' now allows to hide from "fact" name space as well.
  3705 
  3706 * Eliminated destructive theorem database, simpset, claset, and
  3707 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3708 update of theories within ML code.
  3709 
  3710 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3711 INCOMPATIBILITY, object-logics depending on former Pure require
  3712 additional setup PureThy.old_appl_syntax_setup; object-logics
  3713 depending on former CPure need to refer to Pure.
  3714 
  3715 * Commands 'use' and 'ML' are now purely functional, operating on
  3716 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3717 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3718 INCOMPATIBILITY.
  3719 
  3720 * Command 'setup': discontinued implicit version with ML reference.
  3721 
  3722 * Instantiation target allows for simultaneous specification of class
  3723 instance operations together with an instantiation proof.
  3724 Type-checking phase allows to refer to class operations uniformly.
  3725 See src/HOL/Complex/Complex.thy for an Isar example and
  3726 src/HOL/Library/Eval.thy for an ML example.
  3727 
  3728 * Indexing of literal facts: be more serious about including only
  3729 facts from the visible specification/proof context, but not the
  3730 background context (locale etc.).  Affects `prop` notation and method
  3731 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3732 situations.
  3733 
  3734 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3735 "(open)" option, which used to expose internal bound variables to the
  3736 proof text.
  3737 
  3738 * Isar statements: removed obsolete case "rule_context".
  3739 INCOMPATIBILITY, better use explicit fixes/assumes.
  3740 
  3741 * Locale proofs: default proof step now includes 'unfold_locales';
  3742 hence 'proof' without argument may be used to unfold locale
  3743 predicates.
  3744 
  3745 
  3746 *** Document preparation ***
  3747 
  3748 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3749 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3750 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3751 spot); renamed link color from "darkblue" to "linkcolor" (default
  3752 value unchanged, can be redefined via \definecolor); no longer sets
  3753 "a4paper" option (unnecessary or even intrusive).
  3754 
  3755 * Antiquotation @{lemma A method} proves proposition A by the given
  3756 method (either a method name or a method name plus (optional) method
  3757 arguments in parentheses) and prints A just like @{prop A}.
  3758 
  3759 
  3760 *** HOL ***
  3761 
  3762 * New primrec package.  Specification syntax conforms in style to
  3763 definition/function/....  No separate induction rule is provided.  The
  3764 "primrec" command distinguishes old-style and new-style specifications
  3765 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3766 When adjusting theories, beware: constants stemming from new-style
  3767 primrec specifications have authentic syntax.
  3768 
  3769 * Metis prover is now an order of magnitude faster, and also works
  3770 with multithreading.
  3771 
  3772 * Metis: the maximum number of clauses that can be produced from a
  3773 theorem is now given by the attribute max_clauses.  Theorems that
  3774 exceed this number are ignored, with a warning printed.
  3775 
  3776 * Sledgehammer no longer produces structured proofs by default. To
  3777 enable, declare [[sledgehammer_full = true]].  Attributes
  3778 reconstruction_modulus, reconstruction_sorts renamed
  3779 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3780 
  3781 * Method "induct_scheme" derives user-specified induction rules
  3782 from well-founded induction and completeness of patterns. This factors
  3783 out some operations that are done internally by the function package
  3784 and makes them available separately.  See
  3785 src/HOL/ex/Induction_Scheme.thy for examples.
  3786 
  3787 * More flexible generation of measure functions for termination
  3788 proofs: Measure functions can be declared by proving a rule of the
  3789 form "is_measure f" and giving it the [measure_function] attribute.
  3790 The "is_measure" predicate is logically meaningless (always true), and
  3791 just guides the heuristic.  To find suitable measure functions, the
  3792 termination prover sets up the goal "is_measure ?f" of the appropriate
  3793 type and generates all solutions by prolog-style backwards proof using
  3794 the declared rules.
  3795 
  3796 This setup also deals with rules like 
  3797 
  3798   "is_measure f ==> is_measure (list_size f)"
  3799 
  3800 which accommodates nested datatypes that recurse through lists.
  3801 Similar rules are predeclared for products and option types.
  3802 
  3803 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3804 
  3805   INCOMPATIBILITIES:
  3806 
  3807   - Definitions of overloaded constants on sets have to be replaced by
  3808     definitions on => and bool.
  3809 
  3810   - Some definitions of overloaded operators on sets can now be proved
  3811     using the definitions of the operators on => and bool.  Therefore,
  3812     the following theorems have been renamed:
  3813 
  3814       subset_def   -> subset_eq
  3815       psubset_def  -> psubset_eq
  3816       set_diff_def -> set_diff_eq
  3817       Compl_def    -> Compl_eq
  3818       Sup_set_def  -> Sup_set_eq
  3819       Inf_set_def  -> Inf_set_eq
  3820       sup_set_def  -> sup_set_eq
  3821       inf_set_def  -> inf_set_eq
  3822 
  3823   - Due to the incompleteness of the HO unification algorithm, some
  3824     rules such as subst may require manual instantiation, if some of
  3825     the unknowns in the rule is a set.
  3826 
  3827   - Higher order unification and forward proofs:
  3828     The proof pattern
  3829 
  3830       have "P (S::'a set)" <...>
  3831       then have "EX S. P S" ..
  3832 
  3833     no longer works (due to the incompleteness of the HO unification
  3834     algorithm) and must be replaced by the pattern
  3835 
  3836       have "EX S. P S"
  3837       proof
  3838         show "P S" <...>
  3839       qed
  3840 
  3841   - Calculational reasoning with subst (or similar rules):
  3842     The proof pattern
  3843 
  3844       have "P (S::'a set)" <...>
  3845       also have "S = T" <...>
  3846       finally have "P T" .
  3847 
  3848     no longer works (for similar reasons as the previous example) and
  3849     must be replaced by something like
  3850 
  3851       have "P (S::'a set)" <...>
  3852       moreover have "S = T" <...>
  3853       ultimately have "P T" by simp
  3854 
  3855   - Tactics or packages written in ML code:
  3856     Code performing pattern matching on types via
  3857 
  3858       Type ("set", [T]) => ...
  3859 
  3860     must be rewritten. Moreover, functions like strip_type or
  3861     binder_types no longer return the right value when applied to a
  3862     type of the form
  3863 
  3864       T1 => ... => Tn => U => bool
  3865 
  3866     rather than
  3867 
  3868       T1 => ... => Tn => U set
  3869 
  3870 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3871 Wellfounded_Relations to theory Wellfounded.
  3872 
  3873 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3874 
  3875 * Class finite no longer treats UNIV as class parameter.  Use class
  3876 enum from theory Library/Enum instead to achieve a similar effect.
  3877 INCOMPATIBILITY.
  3878 
  3879 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3880 and "Cons".  INCOMPATIBILITY.
  3881 
  3882 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3883 Potential INCOMPATIBILITY.
  3884 
  3885 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3886 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3887 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3888 
  3889 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3890 the same name in theory Orderings:
  3891 
  3892   less_trans
  3893   less_linear
  3894   le_imp_less_or_eq
  3895   le_less_trans
  3896   less_le_trans
  3897   less_not_sym
  3898   less_asym
  3899 
  3900 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3901 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3902 and different variable names.
  3903 
  3904 * Library/Option_ord.thy: Canonical order on option type.
  3905 
  3906 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3907 finite maps.
  3908 
  3909 * Library/Countable.thy: Type class for countable types.
  3910 
  3911 * Theory Int: The representation of numerals has changed.  The infix
  3912 operator BIT and the bit datatype with constructors B0 and B1 have
  3913 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3914 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3915 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3916 accordingly.
  3917 
  3918 * Theory Nat: definition of <= and < on natural numbers no longer
  3919 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3920 le_def and less_def have disappeared.  Consider lemmas not_less
  3921 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3922 
  3923 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3924 (whose purpose mainly is for various fold_set functionals) have been
  3925 abandoned in favor of the existing algebraic classes
  3926 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3927 lower_semilattice (resp. upper_semilattice) and linorder.
  3928 INCOMPATIBILITY.
  3929 
  3930 * Theory Transitive_Closure: induct and cases rules now declare proper
  3931 case_names ("base" and "step").  INCOMPATIBILITY.
  3932 
  3933 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3934 lattices.  The form set-specific version is available as
  3935 Inductive.lfp_ordinal_induct_set.
  3936 
  3937 * Renamed theorems "power.simps" to "power_int.simps".
  3938 INCOMPATIBILITY.
  3939 
  3940 * Class semiring_div provides basic abstract properties of semirings
  3941 with division and modulo operations.  Subsumes former class dvd_mod.
  3942 
  3943 * Merged theories IntDef, Numeral and IntArith into unified theory
  3944 Int.  INCOMPATIBILITY.
  3945 
  3946 * Theory Library/Code_Index: type "index" now represents natural
  3947 numbers rather than integers.  INCOMPATIBILITY.
  3948 
  3949 * New class "uminus" with operation "uminus" (split of from class
  3950 "minus" which now only has operation "minus", binary).
  3951 INCOMPATIBILITY.
  3952 
  3953 * Constants "card", "internal_split", "option_map" now with authentic
  3954 syntax.  INCOMPATIBILITY.
  3955 
  3956 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3957 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3958 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3959 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3960 Sup_set_def, le_def, less_def, option_map_def now with object
  3961 equality.  INCOMPATIBILITY.
  3962 
  3963 * Records. Removed K_record, and replaced it by pure lambda term
  3964 %x. c. The simplifier setup is now more robust against eta expansion.
  3965 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3966 
  3967 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3968 
  3969 * Library/ListVector: new theory of arithmetic vector operations.
  3970 
  3971 * Library/Order_Relation: new theory of various orderings as sets of
  3972 pairs.  Defines preorders, partial orders, linear orders and
  3973 well-orders on sets and on types.
  3974 
  3975 
  3976 *** ZF ***
  3977 
  3978 * Renamed some theories to allow to loading both ZF and HOL in the
  3979 same session:
  3980 
  3981   Datatype  -> Datatype_ZF
  3982   Inductive -> Inductive_ZF
  3983   Int       -> Int_ZF
  3984   IntDiv    -> IntDiv_ZF
  3985   Nat       -> Nat_ZF
  3986   List      -> List_ZF
  3987   Main      -> Main_ZF
  3988 
  3989 INCOMPATIBILITY: ZF theories that import individual theories below
  3990 Main might need to be adapted.  Regular theory Main is still
  3991 available, as trivial extension of Main_ZF.
  3992 
  3993 
  3994 *** ML ***
  3995 
  3996 * ML within Isar: antiquotation @{const name} or @{const
  3997 name(typargs)} produces statically-checked Const term.
  3998 
  3999 * Functor NamedThmsFun: data is available to the user as dynamic fact
  4000 (of the same name).  Removed obsolete print command.
  4001 
  4002 * Removed obsolete "use_legacy_bindings" function.
  4003 
  4004 * The ``print mode'' is now a thread-local value derived from a global
  4005 template (the former print_mode reference), thus access becomes
  4006 non-critical.  The global print_mode reference is for session
  4007 management only; user-code should use print_mode_value,
  4008 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  4009 
  4010 * Functions system/system_out provide a robust way to invoke external
  4011 shell commands, with propagation of interrupts (requires Poly/ML
  4012 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  4013 
  4014 
  4015 *** System ***
  4016 
  4017 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  4018 in accordance with Proof General 3.7, which prefers GNU emacs.
  4019 
  4020 * isatool tty runs Isabelle process with plain tty interaction;
  4021 optional line editor may be specified via ISABELLE_LINE_EDITOR
  4022 setting, the default settings attempt to locate "ledit" and "rlwrap".
  4023 
  4024 * isatool browser now works with Cygwin as well, using general
  4025 "javapath" function defined in Isabelle process environment.
  4026 
  4027 * YXML notation provides a simple and efficient alternative to
  4028 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  4029 isatool yxml as described in the Isabelle system manual.
  4030 
  4031 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  4032 provides general wrapper for managing an Isabelle process in a robust
  4033 fashion, with ``cooked'' output from stdin/stderr.
  4034 
  4035 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  4036 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  4037 
  4038 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  4039 way of changing the user's settings is via
  4040 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  4041 script.
  4042 
  4043 * Multithreading.max_threads := 0 refers to the number of actual CPU
  4044 cores of the underlying machine, which is a good starting point for
  4045 optimal performance tuning.  The corresponding usedir option -M allows
  4046 "max" as an alias for "0".  WARNING: does not work on certain versions
  4047 of Mac OS (with Poly/ML 5.1).
  4048 
  4049 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  4050 adverse effect of Isabelle flooding interactive front-ends (notably
  4051 ProofGeneral / XEmacs).
  4052 
  4053 
  4054 
  4055 New in Isabelle2007 (November 2007)
  4056 -----------------------------------
  4057 
  4058 *** General ***
  4059 
  4060 * More uniform information about legacy features, notably a
  4061 warning/error of "Legacy feature: ...", depending on the state of the
  4062 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  4063 legacy features will disappear eventually.
  4064 
  4065 * Theory syntax: the header format ``theory A = B + C:'' has been
  4066 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  4067 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  4068 
  4069 * Theory syntax: the old non-Isar theory file format has been
  4070 discontinued altogether.  Note that ML proof scripts may still be used
  4071 with Isar theories; migration is usually quite simple with the ML
  4072 function use_legacy_bindings.  INCOMPATIBILITY.
  4073 
  4074 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  4075 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  4076 quotes.
  4077 
  4078 * Theory loader: be more serious about observing the static theory
  4079 header specifications (including optional directories), but not the
  4080 accidental file locations of previously successful loads.  The strict
  4081 update policy of former update_thy is now already performed by
  4082 use_thy, so the former has been removed; use_thys updates several
  4083 theories simultaneously, just as 'imports' within a theory header
  4084 specification, but without merging the results.  Potential
  4085 INCOMPATIBILITY: may need to refine theory headers and commands
  4086 ROOT.ML which depend on load order.
  4087 
  4088 * Theory loader: optional support for content-based file
  4089 identification, instead of the traditional scheme of full physical
  4090 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  4091 (cf. the system manual).  The new scheme allows to work with
  4092 non-finished theories in persistent session images, such that source
  4093 files may be moved later on without requiring reloads.
  4094 
  4095 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4096 file (with the same base name as the theory) are considered a legacy
  4097 feature, which will disappear eventually. Even now, the theory loader
  4098 no longer maintains dependencies on such files.
  4099 
  4100 * Syntax: the scope for resolving ambiguities via type-inference is
  4101 now limited to individual terms, instead of whole simultaneous
  4102 specifications as before. This greatly reduces the complexity of the
  4103 syntax module and improves flexibility by separating parsing and
  4104 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  4105 'fixes' etc.) are required in rare situations.
  4106 
  4107 * Syntax: constants introduced by new-style packages ('definition',
  4108 'abbreviation' etc.) are passed through the syntax module in
  4109 ``authentic mode''. This means that associated mixfix annotations
  4110 really stick to such constants, independently of potential name space
  4111 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  4112 trees are represented slightly differently, may need to adapt syntax
  4113 translations accordingly. Use CONST marker in 'translations' and
  4114 @{const_syntax} antiquotation in 'parse_translation' etc.
  4115 
  4116 * Legacy goal package: reduced interface to the bare minimum required
  4117 to keep existing proof scripts running.  Most other user-level
  4118 functions are now part of the OldGoals structure, which is *not* open
  4119 by default (consider isatool expandshort before open OldGoals).
  4120 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  4121 these tend to cause confusion about the actual goal (!) context being
  4122 used here, which is not necessarily the same as the_context().
  4123 
  4124 * Command 'find_theorems': supports "*" wild-card in "name:"
  4125 criterion; "with_dups" option.  Certain ProofGeneral versions might
  4126 support a specific search form (see ProofGeneral/CHANGES).
  4127 
  4128 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  4129 by default, which means that "prems" (and also "fixed variables") are
  4130 suppressed from proof state output.  Note that the ProofGeneral
  4131 settings mechanism allows to change and save options persistently, but
  4132 older versions of Isabelle will fail to start up if a negative prems
  4133 limit is imposed.
  4134 
  4135 * Local theory targets may be specified by non-nested blocks of
  4136 ``context/locale/class ... begin'' followed by ``end''.  The body may
  4137 contain definitions, theorems etc., including any derived mechanism
  4138 that has been implemented on top of these primitives.  This concept
  4139 generalizes the existing ``theorem (in ...)'' towards more versatility
  4140 and scalability.
  4141 
  4142 * Proof General interface: proper undo of final 'end' command;
  4143 discontinued Isabelle/classic mode (ML proof scripts).
  4144 
  4145 
  4146 *** Document preparation ***
  4147 
  4148 * Added antiquotation @{theory name} which prints the given name,
  4149 after checking that it refers to a valid ancestor theory in the
  4150 current context.
  4151 
  4152 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  4153 check the given source text as ML type/structure, printing verbatim.
  4154 
  4155 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  4156 "c args == rhs" given in the current context.  (Any number of
  4157 arguments may be given on the LHS.)
  4158 
  4159 
  4160 *** Pure ***
  4161 
  4162 * The 'class' package offers a combination of axclass and locale to
  4163 achieve Haskell-like type classes in Isabelle.  Definitions and
  4164 theorems within a class context produce both relative results (with
  4165 implicit parameters according to the locale context), and polymorphic
  4166 constants with qualified polymorphism (according to the class
  4167 context).  Within the body context of a 'class' target, a separate
  4168 syntax layer ("user space type system") takes care of converting
  4169 between global polymorphic consts and internal locale representation.
  4170 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  4171 "isatool doc classes" provides a tutorial.
  4172 
  4173 * Generic code generator framework allows to generate executable
  4174 code for ML and Haskell (including Isabelle classes).  A short usage
  4175 sketch:
  4176 
  4177     internal compilation:
  4178         export_code <list of constants (term syntax)> in SML
  4179     writing SML code to a file:
  4180         export_code <list of constants (term syntax)> in SML <filename>
  4181     writing OCaml code to a file:
  4182         export_code <list of constants (term syntax)> in OCaml <filename>
  4183     writing Haskell code to a bunch of files:
  4184         export_code <list of constants (term syntax)> in Haskell <filename>
  4185 
  4186     evaluating closed propositions to True/False using code generation:
  4187         method ``eval''
  4188 
  4189 Reasonable default setup of framework in HOL.
  4190 
  4191 Theorem attributs for selecting and transforming function equations theorems:
  4192 
  4193     [code fun]:        select a theorem as function equation for a specific constant
  4194     [code fun del]:    deselect a theorem as function equation for a specific constant
  4195     [code inline]:     select an equation theorem for unfolding (inlining) in place
  4196     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  4197 
  4198 User-defined serializations (target in {SML, OCaml, Haskell}):
  4199 
  4200     code_const <and-list of constants (term syntax)>
  4201       {(target) <and-list of const target syntax>}+
  4202 
  4203     code_type <and-list of type constructors>
  4204       {(target) <and-list of type target syntax>}+
  4205 
  4206     code_instance <and-list of instances>
  4207       {(target)}+
  4208         where instance ::= <type constructor> :: <class>
  4209 
  4210     code_class <and_list of classes>
  4211       {(target) <and-list of class target syntax>}+
  4212         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4213 
  4214 code_instance and code_class only are effective to target Haskell.
  4215 
  4216 For example usage see src/HOL/ex/Codegenerator.thy and
  4217 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4218 generation from Isabelle/HOL theories is available via "isatool doc
  4219 codegen".
  4220 
  4221 * Code generator: consts in 'consts_code' Isar commands are now
  4222 referred to by usual term syntax (including optional type
  4223 annotations).
  4224 
  4225 * Command 'no_translations' removes translation rules from theory
  4226 syntax.
  4227 
  4228 * Overloaded definitions are now actually checked for acyclic
  4229 dependencies.  The overloading scheme is slightly more general than
  4230 that of Haskell98, although Isabelle does not demand an exact
  4231 correspondence to type class and instance declarations.
  4232 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4233 exotic versions of overloading -- at the discretion of the user!
  4234 
  4235 Polymorphic constants are represented via type arguments, i.e. the
  4236 instantiation that matches an instance against the most general
  4237 declaration given in the signature.  For example, with the declaration
  4238 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4239 as c(nat).  Overloading is essentially simultaneous structural
  4240 recursion over such type arguments.  Incomplete specification patterns
  4241 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4242 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4243 Command 'print_theory' outputs the normalized system of recursive
  4244 equations, see section "definitions".
  4245 
  4246 * Configuration options are maintained within the theory or proof
  4247 context (with name and type bool/int/string), providing a very simple
  4248 interface to a poor-man's version of general context data.  Tools may
  4249 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4250 these values using Config.get etc.  Users may change options via an
  4251 associated attribute of the same name.  This form of context
  4252 declaration works particularly well with commands 'declare' or
  4253 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4254 very easy to avoid global references, which would not observe Isar
  4255 toplevel undo/redo and fail to work with multithreading.
  4256 
  4257 Various global ML references of Pure and HOL have been turned into
  4258 configuration options:
  4259 
  4260   Unify.search_bound		unify_search_bound
  4261   Unify.trace_bound		unify_trace_bound
  4262   Unify.trace_simp		unify_trace_simp
  4263   Unify.trace_types		unify_trace_types
  4264   Simplifier.simp_depth_limit	simp_depth_limit
  4265   Blast.depth_limit		blast_depth_limit
  4266   DatatypeProp.dtK		datatype_distinctness_limit
  4267   fast_arith_neq_limit  	fast_arith_neq_limit
  4268   fast_arith_split_limit	fast_arith_split_limit
  4269 
  4270 * Named collections of theorems may be easily installed as context
  4271 data using the functor NamedThmsFun (see also
  4272 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4273 attributes; there is also a toplevel print command.  This facility is
  4274 just a common case of general context data, which is the preferred way
  4275 for anything more complex than just a list of facts in canonical
  4276 order.
  4277 
  4278 * Isar: command 'declaration' augments a local theory by generic
  4279 declaration functions written in ML.  This enables arbitrary content
  4280 being added to the context, depending on a morphism that tells the
  4281 difference of the original declaration context wrt. the application
  4282 context encountered later on.
  4283 
  4284 * Isar: proper interfaces for simplification procedures.  Command
  4285 'simproc_setup' declares named simprocs (with match patterns, and body
  4286 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4287 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4288 
  4289 * Isar: an extra pair of brackets around attribute declarations
  4290 abbreviates a theorem reference involving an internal dummy fact,
  4291 which will be ignored later --- only the effect of the attribute on
  4292 the background context will persist.  This form of in-place
  4293 declarations is particularly useful with commands like 'declare' and
  4294 'using', for example ``have A using [[simproc a]] by simp''.
  4295 
  4296 * Isar: method "assumption" (and implicit closing of subproofs) now
  4297 takes simple non-atomic goal assumptions into account: after applying
  4298 an assumption as a rule the resulting subgoals are solved by atomic
  4299 assumption steps.  This is particularly useful to finish 'obtain'
  4300 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4301 without referring to the original premise "!!x. P x ==> thesis" in the
  4302 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4303 more permissive.
  4304 
  4305 * Isar: implicit use of prems from the Isar proof context is
  4306 considered a legacy feature.  Common applications like ``have A .''
  4307 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4308 referencing facts explicitly here improves readability and
  4309 maintainability of proof texts.
  4310 
  4311 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4312 the obtained context from the course of reasoning!  For example:
  4313 
  4314   assume "EX x y. A x & B y"   -- "any previous fact"
  4315   then guess x and y by clarify
  4316 
  4317 This technique is potentially adventurous, depending on the facts and
  4318 proof tools being involved here.
  4319 
  4320 * Isar: known facts from the proof context may be specified as literal
  4321 propositions, using ASCII back-quote syntax.  This works wherever
  4322 named facts used to be allowed so far, in proof commands, proof
  4323 methods, attributes etc.  Literal facts are retrieved from the context
  4324 according to unification of type and term parameters.  For example,
  4325 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4326 theorems in the current context, then these are valid literal facts:
  4327 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4328 
  4329 There is also a proof method "fact" which does the same composition
  4330 for explicit goal states, e.g. the following proof texts coincide with
  4331 certain special cases of literal facts:
  4332 
  4333   have "A" by fact                 ==  note `A`
  4334   have "A ==> B" by fact           ==  note `A ==> B`
  4335   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4336   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4337 
  4338 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4339 outer syntax.  Thus symbolic identifiers may be used without
  4340 additional white space in declarations like this: ``assume *: A''.
  4341 
  4342 * Isar: 'print_facts' prints all local facts of the current context,
  4343 both named and unnamed ones.
  4344 
  4345 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4346 
  4347   def x == "t" and y == "u"
  4348 
  4349 * Isar: added command 'unfolding', which is structurally similar to
  4350 'using', but affects both the goal state and facts by unfolding given
  4351 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4352 'unfolded' attribute may be replaced by first-class proof text.
  4353 
  4354 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4355 and command 'unfolding' now all support object-level equalities
  4356 (potentially conditional).  The underlying notion of rewrite rule is
  4357 analogous to the 'rule_format' attribute, but *not* that of the
  4358 Simplifier (which is usually more generous).
  4359 
  4360 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4361 premises of a theorem by n. Useful in conjunction with drule.
  4362 
  4363 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4364 method expression within a sandbox consisting of the first N
  4365 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4366 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4367 simplifies all new goals that emerge from applying rule foo to the
  4368 originally first one.
  4369 
  4370 * Isar: schematic goals are no longer restricted to higher-order
  4371 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4372 expected.
  4373 
  4374 * Isar: the conclusion of a long theorem statement is now either
  4375 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4376 (essentially a disjunction of cases with local parameters and
  4377 assumptions).  The latter allows to express general elimination rules
  4378 adequately; in this notation common elimination rules look like this:
  4379 
  4380   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4381     assumes "EX x. P x"
  4382     obtains x where "P x"
  4383 
  4384   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4385     assumes "A & B"
  4386     obtains A and B
  4387 
  4388   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4389     assumes "A | B"
  4390     obtains
  4391       A
  4392     | B
  4393 
  4394 The subsequent classical rules even refer to the formal "thesis"
  4395 explicitly:
  4396 
  4397   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4398     obtains "~ thesis"
  4399 
  4400   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4401     obtains "thesis ==> something"
  4402 
  4403 The actual proof of an 'obtains' statement is analogous to that of the
  4404 Isar proof element 'obtain', only that there may be several cases.
  4405 Optional case names may be specified in parentheses; these will be
  4406 available both in the present proof and as annotations in the
  4407 resulting rule, for later use with the 'cases' method (cf. attribute
  4408 case_names).
  4409 
  4410 * Isar: the assumptions of a long theorem statement are available as
  4411 "assms" fact in the proof context.  This is more appropriate than the
  4412 (historical) "prems", which refers to all assumptions of the current
  4413 context, including those from the target locale, proof body etc.
  4414 
  4415 * Isar: 'print_statement' prints theorems from the current theory or
  4416 proof context in long statement form, according to the syntax of a
  4417 top-level lemma.
  4418 
  4419 * Isar: 'obtain' takes an optional case name for the local context
  4420 introduction rule (default "that").
  4421 
  4422 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4423 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4424 to occur.
  4425 
  4426 * Pure: syntax "CONST name" produces a fully internalized constant
  4427 according to the current context.  This is particularly useful for
  4428 syntax translations that should refer to internal constant
  4429 representations independently of name spaces.
  4430 
  4431 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4432 instead of "FOO ". This allows multiple binder declarations to coexist
  4433 in the same context.  INCOMPATIBILITY.
  4434 
  4435 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4436 primitive that also works in a locale context (both for constants and
  4437 fixed variables). Type declaration and internal syntactic representation
  4438 of given constants retrieved from the context. Likewise, the
  4439 'no_notation' command allows to remove given syntax annotations from the
  4440 current context.
  4441 
  4442 * Isar/locales: new derived specification elements 'axiomatization',
  4443 'definition', 'abbreviation', which support type-inference, admit
  4444 object-level specifications (equality, equivalence).  See also the
  4445 isar-ref manual.  Examples:
  4446 
  4447   axiomatization
  4448     eq  (infix "===" 50) where
  4449     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4450 
  4451   definition "f x y = x + y + 1"
  4452   definition g where "g x = f x x"
  4453 
  4454   abbreviation
  4455     neq  (infix "=!=" 50) where
  4456     "x =!= y == ~ (x === y)"
  4457 
  4458 These specifications may be also used in a locale context.  Then the
  4459 constants being introduced depend on certain fixed parameters, and the
  4460 constant name is qualified by the locale base name.  An internal
  4461 abbreviation takes care for convenient input and output, making the
  4462 parameters implicit and using the original short name.  See also
  4463 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4464 entities from a monomorphic theory.
  4465 
  4466 Presently, abbreviations are only available 'in' a target locale, but
  4467 not inherited by general import expressions.  Also note that
  4468 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4469 'translations' in common applications.  The "no_abbrevs" print mode
  4470 prevents folding of abbreviations in term output.
  4471 
  4472 Concrete syntax is attached to specified constants in internal form,
  4473 independently of name spaces.  The parse tree representation is
  4474 slightly different -- use 'notation' instead of raw 'syntax', and
  4475 'translations' with explicit "CONST" markup to accommodate this.
  4476 
  4477 * Pure/Isar: unified syntax for new-style specification mechanisms
  4478 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4479 full type inference and dummy patterns ("_").  For example:
  4480 
  4481   definition "K x _ = x"
  4482 
  4483   inductive conj for A B
  4484   where "A ==> B ==> conj A B"
  4485 
  4486 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4487 the current context.  Print mode "no_abbrevs" prevents inversion of
  4488 abbreviations on output.
  4489 
  4490 * Isar/locales: improved parameter handling: use of locales "var" and
  4491 "struct" no longer necessary; - parameter renamings are no longer
  4492 required to be injective.  For example, this allows to define
  4493 endomorphisms as locale endom = homom mult mult h.
  4494 
  4495 * Isar/locales: changed the way locales with predicates are defined.
  4496 Instead of accumulating the specification, the imported expression is
  4497 now an interpretation.  INCOMPATIBILITY: different normal form of
  4498 locale expressions.  In particular, in interpretations of locales with
  4499 predicates, goals repesenting already interpreted fragments are not
  4500 removed automatically.  Use methods `intro_locales' and
  4501 `unfold_locales'; see below.
  4502 
  4503 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4504 provide backward reasoning on locales predicates.  The methods are
  4505 aware of interpretations and discharge corresponding goals.
  4506 `intro_locales' is less aggressive then `unfold_locales' and does not
  4507 unfold predicates to assumptions.
  4508 
  4509 * Isar/locales: the order in which locale fragments are accumulated
  4510 has changed.  This enables to override declarations from fragments due
  4511 to interpretations -- for example, unwanted simp rules.
  4512 
  4513 * Isar/locales: interpretation in theories and proof contexts has been
  4514 extended.  One may now specify (and prove) equations, which are
  4515 unfolded in interpreted theorems.  This is useful for replacing
  4516 defined concepts (constants depending on locale parameters) by
  4517 concepts already existing in the target context.  Example:
  4518 
  4519   interpretation partial_order ["op <= :: [int, int] => bool"]
  4520     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4521 
  4522 Typically, the constant `partial_order.less' is created by a
  4523 definition specification element in the context of locale
  4524 partial_order.
  4525 
  4526 * Method "induct": improved internal context management to support
  4527 local fixes and defines on-the-fly. Thus explicit meta-level
  4528 connectives !!  and ==> are rarely required anymore in inductive goals
  4529 (using object-logic connectives for this purpose has been long
  4530 obsolete anyway). Common proof patterns are explained in
  4531 src/HOL/Induct/Common_Patterns.thy, see also
  4532 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4533 examples.
  4534 
  4535 * Method "induct": improved handling of simultaneous goals. Instead of
  4536 introducing object-level conjunction, the statement is now split into
  4537 several conclusions, while the corresponding symbolic cases are nested
  4538 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4539 see src/HOL/Induct/Common_Patterns.thy, for example.
  4540 
  4541 * Method "induct": mutual induction rules are now specified as a list
  4542 of rule sharing the same induction cases. HOL packages usually provide
  4543 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4544 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4545 mutual induction rules differently, i.e. like this:
  4546 
  4547   (induct rule: foo_bar.inducts)
  4548   (induct set: foo bar)
  4549   (induct pred: foo bar)
  4550   (induct type: foo bar)
  4551 
  4552 The ML function ProjectRule.projections turns old-style rules into the
  4553 new format.
  4554 
  4555 * Method "coinduct": dual of induction, see
  4556 src/HOL/Library/Coinductive_List.thy for various examples.
  4557 
  4558 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4559 considered a legacy feature.
  4560 
  4561 * Attribute "symmetric" produces result with standardized schematic
  4562 variables (index 0).  Potential INCOMPATIBILITY.
  4563 
  4564 * Simplifier: by default the simplifier trace only shows top level
  4565 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4566 default. Thus there is less danger of being flooded by the trace. The
  4567 trace indicates where parts have been suppressed.
  4568   
  4569 * Provers/classical: removed obsolete classical version of elim_format
  4570 attribute; classical elim/dest rules are now treated uniformly when
  4571 manipulating the claset.
  4572 
  4573 * Provers/classical: stricter checks to ensure that supplied intro,
  4574 dest and elim rules are well-formed; dest and elim rules must have at
  4575 least one premise.
  4576 
  4577 * Provers/classical: attributes dest/elim/intro take an optional
  4578 weight argument for the rule (just as the Pure versions).  Weights are
  4579 ignored by automated tools, but determine the search order of single
  4580 rule steps.
  4581 
  4582 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4583 where the body does not mention the bound variable.  Note that dummy
  4584 patterns implicitly depend on their context of bounds, which makes
  4585 "{_. _}" match any set comprehension as expected.  Potential
  4586 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4587 constant "_idtdummy" in the binding position.
  4588 
  4589 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4590 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4591 for example "A -> B" => "Pi A (%_. B)".
  4592 
  4593 * Pure: 'class_deps' command visualizes the subclass relation, using
  4594 the graph browser tool.
  4595 
  4596 * Pure: 'print_theory' now suppresses certain internal declarations by
  4597 default; use '!' option for full details.
  4598 
  4599 
  4600 *** HOL ***
  4601 
  4602 * Method "metis" proves goals by applying the Metis general-purpose
  4603 resolution prover (see also http://gilith.com/software/metis/).
  4604 Examples are in the directory MetisExamples.  WARNING: the
  4605 Isabelle/HOL-Metis integration does not yet work properly with
  4606 multi-threading.
  4607   
  4608 * Command 'sledgehammer' invokes external automatic theorem provers as
  4609 background processes.  It generates calls to the "metis" method if
  4610 successful. These can be pasted into the proof.  Users do not have to
  4611 wait for the automatic provers to return.  WARNING: does not really
  4612 work with multi-threading.
  4613 
  4614 * New "auto_quickcheck" feature tests outermost goal statements for
  4615 potential counter-examples.  Controlled by ML references
  4616 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4617 5000 milliseconds).  Fails silently if statements is outside of
  4618 executable fragment, or any other codgenerator problem occurs.
  4619 
  4620 * New constant "undefined" with axiom "undefined x = undefined".
  4621 
  4622 * Added class "HOL.eq", allowing for code generation with polymorphic
  4623 equality.
  4624 
  4625 * Some renaming of class constants due to canonical name prefixing in
  4626 the new 'class' package:
  4627 
  4628     HOL.abs ~> HOL.abs_class.abs
  4629     HOL.divide ~> HOL.divide_class.divide
  4630     0 ~> HOL.zero_class.zero
  4631     1 ~> HOL.one_class.one
  4632     op + ~> HOL.plus_class.plus
  4633     op - ~> HOL.minus_class.minus
  4634     uminus ~> HOL.minus_class.uminus
  4635     op * ~> HOL.times_class.times
  4636     op < ~> HOL.ord_class.less
  4637     op <= > HOL.ord_class.less_eq
  4638     Nat.power ~> Power.power_class.power
  4639     Nat.size ~> Nat.size_class.size
  4640     Numeral.number_of ~> Numeral.number_class.number_of
  4641     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4642     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4643     Orderings.min ~> Orderings.ord_class.min
  4644     Orderings.max ~> Orderings.ord_class.max
  4645     Divides.op div ~> Divides.div_class.div
  4646     Divides.op mod ~> Divides.div_class.mod
  4647     Divides.op dvd ~> Divides.div_class.dvd
  4648 
  4649 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4650 
  4651 a) User-defined constants using any of the names "plus", "minus",
  4652 "times", "less" or "less_eq". The standard syntax translations for
  4653 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4654 names.
  4655 
  4656 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4657 INCOMPATIBILITY: use more specific names.
  4658 
  4659 c) Permutative equations (e.g. "a + b = b + a")
  4660 Since the change of names also changes the order of terms, permutative
  4661 rewrite rules may get applied in a different order. Experience shows
  4662 that this is rarely the case (only two adaptions in the whole Isabelle
  4663 distribution).  INCOMPATIBILITY: rewrite proofs
  4664 
  4665 d) ML code directly refering to constant names
  4666 This in general only affects hand-written proof tactics, simprocs and
  4667 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4668 Consider using @{const_name} antiquotation.
  4669 
  4670 * New class "default" with associated constant "default".
  4671 
  4672 * Function "sgn" is now overloaded and available on int, real, complex
  4673 (and other numeric types), using class "sgn".  Two possible defs of
  4674 sgn are given as equational assumptions in the classes sgn_if and
  4675 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4676 INCOMPATIBILITY.
  4677 
  4678 * Locale "partial_order" now unified with class "order" (cf. theory
  4679 Orderings), added parameter "less".  INCOMPATIBILITY.
  4680 
  4681 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4682 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4683 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4684 
  4685 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4686 changed order of proof goals in instance proofs.
  4687 
  4688 * The transitivity reasoner for partial and linear orders is set up
  4689 for classes "order" and "linorder".  Instances of the reasoner are available
  4690 in all contexts importing or interpreting the corresponding locales.
  4691 Method "order" invokes the reasoner separately; the reasoner
  4692 is also integrated with the Simplifier as a solver.  Diagnostic
  4693 command 'print_orders' shows the available instances of the reasoner
  4694 in the current context.
  4695 
  4696 * Localized monotonicity predicate in theory "Orderings"; integrated
  4697 lemmas max_of_mono and min_of_mono with this predicate.
  4698 INCOMPATIBILITY.
  4699 
  4700 * Formulation of theorem "dense" changed slightly due to integration
  4701 with new class dense_linear_order.
  4702 
  4703 * Uniform lattice theory development in HOL.
  4704 
  4705     constants "meet" and "join" now named "inf" and "sup"
  4706     constant "Meet" now named "Inf"
  4707 
  4708     classes "meet_semilorder" and "join_semilorder" now named
  4709       "lower_semilattice" and "upper_semilattice"
  4710     class "lorder" now named "lattice"
  4711     class "comp_lat" now named "complete_lattice"
  4712 
  4713     Instantiation of lattice classes allows explicit definitions
  4714     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4715 
  4716   INCOMPATIBILITY.  Theorem renames:
  4717 
  4718     meet_left_le            ~> inf_le1
  4719     meet_right_le           ~> inf_le2
  4720     join_left_le            ~> sup_ge1
  4721     join_right_le           ~> sup_ge2
  4722     meet_join_le            ~> inf_sup_ord
  4723     le_meetI                ~> le_infI
  4724     join_leI                ~> le_supI
  4725     le_meet                 ~> le_inf_iff
  4726     le_join                 ~> ge_sup_conv
  4727     meet_idempotent         ~> inf_idem
  4728     join_idempotent         ~> sup_idem
  4729     meet_comm               ~> inf_commute
  4730     join_comm               ~> sup_commute
  4731     meet_leI1               ~> le_infI1
  4732     meet_leI2               ~> le_infI2
  4733     le_joinI1               ~> le_supI1
  4734     le_joinI2               ~> le_supI2
  4735     meet_assoc              ~> inf_assoc
  4736     join_assoc              ~> sup_assoc
  4737     meet_left_comm          ~> inf_left_commute
  4738     meet_left_idempotent    ~> inf_left_idem
  4739     join_left_comm          ~> sup_left_commute
  4740     join_left_idempotent    ~> sup_left_idem
  4741     meet_aci                ~> inf_aci
  4742     join_aci                ~> sup_aci
  4743     le_def_meet             ~> le_iff_inf
  4744     le_def_join             ~> le_iff_sup
  4745     join_absorp2            ~> sup_absorb2
  4746     join_absorp1            ~> sup_absorb1
  4747     meet_absorp1            ~> inf_absorb1
  4748     meet_absorp2            ~> inf_absorb2
  4749     meet_join_absorp        ~> inf_sup_absorb
  4750     join_meet_absorp        ~> sup_inf_absorb
  4751     distrib_join_le         ~> distrib_sup_le
  4752     distrib_meet_le         ~> distrib_inf_le
  4753 
  4754     add_meet_distrib_left   ~> add_inf_distrib_left
  4755     add_join_distrib_left   ~> add_sup_distrib_left
  4756     is_join_neg_meet        ~> is_join_neg_inf
  4757     is_meet_neg_join        ~> is_meet_neg_sup
  4758     add_meet_distrib_right  ~> add_inf_distrib_right
  4759     add_join_distrib_right  ~> add_sup_distrib_right
  4760     add_meet_join_distribs  ~> add_sup_inf_distribs
  4761     join_eq_neg_meet        ~> sup_eq_neg_inf
  4762     meet_eq_neg_join        ~> inf_eq_neg_sup
  4763     add_eq_meet_join        ~> add_eq_inf_sup
  4764     meet_0_imp_0            ~> inf_0_imp_0
  4765     join_0_imp_0            ~> sup_0_imp_0
  4766     meet_0_eq_0             ~> inf_0_eq_0
  4767     join_0_eq_0             ~> sup_0_eq_0
  4768     neg_meet_eq_join        ~> neg_inf_eq_sup
  4769     neg_join_eq_meet        ~> neg_sup_eq_inf
  4770     join_eq_if              ~> sup_eq_if
  4771 
  4772     mono_meet               ~> mono_inf
  4773     mono_join               ~> mono_sup
  4774     meet_bool_eq            ~> inf_bool_eq
  4775     join_bool_eq            ~> sup_bool_eq
  4776     meet_fun_eq             ~> inf_fun_eq
  4777     join_fun_eq             ~> sup_fun_eq
  4778     meet_set_eq             ~> inf_set_eq
  4779     join_set_eq             ~> sup_set_eq
  4780     meet1_iff               ~> inf1_iff
  4781     meet2_iff               ~> inf2_iff
  4782     meet1I                  ~> inf1I
  4783     meet2I                  ~> inf2I
  4784     meet1D1                 ~> inf1D1
  4785     meet2D1                 ~> inf2D1
  4786     meet1D2                 ~> inf1D2
  4787     meet2D2                 ~> inf2D2
  4788     meet1E                  ~> inf1E
  4789     meet2E                  ~> inf2E
  4790     join1_iff               ~> sup1_iff
  4791     join2_iff               ~> sup2_iff
  4792     join1I1                 ~> sup1I1
  4793     join2I1                 ~> sup2I1
  4794     join1I1                 ~> sup1I1
  4795     join2I2                 ~> sup1I2
  4796     join1CI                 ~> sup1CI
  4797     join2CI                 ~> sup2CI
  4798     join1E                  ~> sup1E
  4799     join2E                  ~> sup2E
  4800 
  4801     is_meet_Meet            ~> is_meet_Inf
  4802     Meet_bool_def           ~> Inf_bool_def
  4803     Meet_fun_def            ~> Inf_fun_def
  4804     Meet_greatest           ~> Inf_greatest
  4805     Meet_lower              ~> Inf_lower
  4806     Meet_set_def            ~> Inf_set_def
  4807 
  4808     Sup_def                 ~> Sup_Inf
  4809     Sup_bool_eq             ~> Sup_bool_def
  4810     Sup_fun_eq              ~> Sup_fun_def
  4811     Sup_set_eq              ~> Sup_set_def
  4812 
  4813     listsp_meetI            ~> listsp_infI
  4814     listsp_meet_eq          ~> listsp_inf_eq
  4815 
  4816     meet_min                ~> inf_min
  4817     join_max                ~> sup_max
  4818 
  4819 * Added syntactic class "size"; overloaded constant "size" now has
  4820 type "'a::size ==> bool"
  4821 
  4822 * Internal reorganisation of `size' of datatypes: size theorems
  4823 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4824 simplification rules by default!); theorems "prod.size" now named
  4825 "*.size".
  4826 
  4827 * Class "div" now inherits from class "times" rather than "type".
  4828 INCOMPATIBILITY.
  4829 
  4830 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4831 Linorder etc.  have disappeared; operations defined in terms of
  4832 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4833 
  4834 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4835 
  4836 * HOL-Word: New extensive library and type for generic, fixed size
  4837 machine words, with arithmetic, bit-wise, shifting and rotating
  4838 operations, reflection into int, nat, and bool lists, automation for
  4839 linear arithmetic (by automatic reflection into nat or int), including
  4840 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4841 arithmetic type classes, supporting automatic simplification of
  4842 numerals on all operations.
  4843 
  4844 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4845 
  4846 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4847 
  4848 * Code generator library theories:
  4849   - Code_Integer represents HOL integers by big integer literals in target
  4850     languages.
  4851   - Code_Char represents HOL characters by character literals in target
  4852     languages.
  4853   - Code_Char_chr like Code_Char, but also offers treatment of character
  4854     codes; includes Code_Integer.
  4855   - Executable_Set allows to generate code for finite sets using lists.
  4856   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4857     denominator).
  4858   - Executable_Real implements a subset of real numbers, namly those
  4859     representable by rational numbers.
  4860   - Efficient_Nat implements natural numbers by integers, which in general will
  4861     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4862     includes Code_Integer.
  4863   - Code_Index provides an additional datatype index which is mapped to
  4864     target-language built-in integers.
  4865   - Code_Message provides an additional datatype message_string which is isomorphic to
  4866     strings; messages are mapped to target-language strings.
  4867 
  4868 * New package for inductive predicates
  4869 
  4870   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4871 
  4872     inductive
  4873       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4874       for z_1 :: U_1 and ... and z_n :: U_m
  4875     where
  4876       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4877     | ...
  4878 
  4879   with full support for type-inference, rather than
  4880 
  4881     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4882 
  4883     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4884     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4885 
  4886     inductive "s z_1 ... z_m"
  4887     intros
  4888       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4889       ...
  4890 
  4891   For backward compatibility, there is a wrapper allowing inductive
  4892   sets to be defined with the new package via
  4893 
  4894     inductive_set
  4895       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4896       for z_1 :: U_1 and ... and z_n :: U_m
  4897     where
  4898       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4899     | ...
  4900 
  4901   or
  4902 
  4903     inductive_set
  4904       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4905       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4906       for z_1 :: U_1 and ... and z_n :: U_m
  4907     where
  4908       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4909     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4910     | ...
  4911 
  4912   if the additional syntax "p ..." is required.
  4913 
  4914   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4915   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4916 
  4917   INCOMPATIBILITIES:
  4918 
  4919   - Since declaration and definition of inductive sets or predicates
  4920     is no longer separated, abbreviations involving the newly
  4921     introduced sets or predicates must be specified together with the
  4922     introduction rules after the 'where' keyword (see above), rather
  4923     than before the actual inductive definition.
  4924 
  4925   - The variables in induction and elimination rules are now
  4926     quantified in the order of their occurrence in the introduction
  4927     rules, rather than in alphabetical order. Since this may break
  4928     some proofs, these proofs either have to be repaired, e.g. by
  4929     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4930     statements of the form
  4931 
  4932       case (rule_i a_i_1 ... a_i_{k_i})
  4933 
  4934     or the old order of quantification has to be restored by explicitly adding
  4935     meta-level quantifiers in the introduction rules, i.e.
  4936 
  4937       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4938 
  4939   - The format of the elimination rules is now
  4940 
  4941       p z_1 ... z_m x_1 ... x_n ==>
  4942         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4943         ==> ... ==> P
  4944 
  4945     for predicates and
  4946 
  4947       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4948         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4949         ==> ... ==> P
  4950 
  4951     for sets rather than
  4952 
  4953       x : s z_1 ... z_m ==>
  4954         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4955         ==> ... ==> P
  4956 
  4957     This may require terms in goals to be expanded to n-tuples
  4958     (e.g. using case_tac or simplification with the split_paired_all
  4959     rule) before the above elimination rule is applicable.
  4960 
  4961   - The elimination or case analysis rules for (mutually) inductive
  4962     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4963     list of rules "p_1_..._p_k.elims" is no longer available.
  4964 
  4965 * New package "function"/"fun" for general recursive functions,
  4966 supporting mutual and nested recursion, definitions in local contexts,
  4967 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4968 for small examples, and the separate tutorial on the function
  4969 package. The old recdef "package" is still available as before, but
  4970 users are encouraged to use the new package.
  4971 
  4972 * Method "lexicographic_order" automatically synthesizes termination
  4973 relations as lexicographic combinations of size measures. 
  4974 
  4975 * Case-expressions allow arbitrary constructor-patterns (including
  4976 "_") and take their order into account, like in functional
  4977 programming.  Internally, this is translated into nested
  4978 case-expressions; missing cases are added and mapped to the predefined
  4979 constant "undefined". In complicated cases printing may no longer show
  4980 the original input but the internal form. Lambda-abstractions allow
  4981 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4982 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4983 variable.
  4984 
  4985 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4986 is an abbreviation for "of_nat :: nat => int". The simplification
  4987 rules for "of_nat" have been changed to work like "int" did
  4988 previously.  Potential INCOMPATIBILITY:
  4989   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4990   - of_nat_diff and of_nat_mult are no longer default simp rules
  4991 
  4992 * Method "algebra" solves polynomial equations over (semi)rings using
  4993 Groebner bases. The (semi)ring structure is defined by locales and the
  4994 tool setup depends on that generic context. Installing the method for
  4995 a specific type involves instantiating the locale and possibly adding
  4996 declarations for computation on the coefficients.  The method is
  4997 already instantiated for natural numbers and for the axiomatic class
  4998 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4999 CALCULEMUS 2007 for the general principles underlying this
  5000 architecture of context-aware proof-tools.
  5001 
  5002 * Method "ferrack" implements quantifier elimination over
  5003 special-purpose dense linear orders using locales (analogous to
  5004 "algebra"). The method is already installed for class
  5005 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  5006 rat, etc.
  5007 
  5008 * Former constant "List.op @" now named "List.append".  Use ML
  5009 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  5010 circumvent possible incompatibilities when working on ML level.
  5011 
  5012 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  5013 
  5014 * New function listsum :: 'a list => 'a for arbitrary monoids.
  5015 Special syntax: "SUM x <- xs. f x" (and latex variants)
  5016 
  5017 * New syntax for Haskell-like list comprehension (input only), eg.
  5018 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  5019 
  5020 * The special syntax for function "filter" has changed from [x :
  5021 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  5022 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  5023 
  5024 * [a..b] is now defined for arbitrary linear orders.  It used to be
  5025 defined on nat only, as an abbreviation for [a..<Suc b]
  5026 INCOMPATIBILITY.
  5027 
  5028 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  5029 
  5030 * New functions "sorted" and "sort" in src/HOL/List.thy.
  5031 
  5032 * New lemma collection field_simps (an extension of ring_simps) for
  5033 manipulating (in)equations involving division. Multiplies with all
  5034 denominators that can be proved to be non-zero (in equations) or
  5035 positive/negative (in inequations).
  5036 
  5037 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  5038 have been improved and renamed to ring_simps, group_simps and
  5039 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  5040 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  5041 
  5042 * Theory Library/Commutative_Ring: switched from recdef to function
  5043 package; constants add, mul, pow now curried.  Infix syntax for
  5044 algebraic operations.
  5045 
  5046 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  5047 INCOMPATIBILITY.
  5048 
  5049 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  5050 INCOMPATIBILITY.
  5051 
  5052 * HOL/records: generalised field-update to take a function on the
  5053 field rather than the new value: r(|A := x|) is translated to A_update
  5054 (K x) r The K-combinator that is internally used is called K_record.
  5055 INCOMPATIBILITY: Usage of the plain update functions has to be
  5056 adapted.
  5057  
  5058 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  5059 * x = 0, which are required for a semiring.  Richer structures do not
  5060 inherit from semiring_0 anymore, because this property is a theorem
  5061 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  5062 there is more to prove, but this is mostly trivial.
  5063 
  5064 * Class "recpower" is generalized to arbitrary monoids, not just
  5065 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  5066 commutativity or semiring properties additionally.
  5067 
  5068 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  5069 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  5070 better use 'abbreviation'.
  5071 
  5072 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  5073 
  5074 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  5075 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  5076 significant changes for setting up numeral syntax for types:
  5077   - New constants Numeral.pred and Numeral.succ instead
  5078       of former Numeral.bin_pred and Numeral.bin_succ.
  5079   - Use integer operations instead of bin_add, bin_mult and so on.
  5080   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  5081   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  5082 
  5083 See src/HOL/Integ/IntArith.thy for an example setup.
  5084 
  5085 * Command 'normal_form' computes the normal form of a term that may
  5086 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  5087 produces ``[b, c, a]'' (without proof).  This command is suitable for
  5088 heavy-duty computations because the functions are compiled to ML
  5089 first.  Correspondingly, a method "normalization" is provided.  See
  5090 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  5091 
  5092 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  5093 25 like -->); output depends on the "iff" print_mode, the default is
  5094 "A = B" (with priority 50).
  5095 
  5096 * Relations less (<) and less_eq (<=) are also available on type bool.
  5097 Modified syntax to disallow nesting without explicit parentheses,
  5098 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  5099 INCOMPATIBILITY.
  5100 
  5101 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  5102 
  5103 * Relation composition operator "op O" now has precedence 75 and binds
  5104 stronger than union and intersection. INCOMPATIBILITY.
  5105 
  5106 * The old set interval syntax "{m..n(}" (and relatives) has been
  5107 removed.  Use "{m..<n}" (and relatives) instead.
  5108 
  5109 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  5110 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  5111 ``declare [[simproc del: neq]]''.
  5112 
  5113 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  5114 True/False.
  5115 
  5116 * Theorem Cons_eq_map_conv no longer declared as "simp".
  5117 
  5118 * Theorem setsum_mult renamed to setsum_right_distrib.
  5119 
  5120 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  5121 ``rule'' method.
  5122 
  5123 * Reimplemented methods "sat" and "satx", with several improvements:
  5124 goals no longer need to be stated as "<prems> ==> False", equivalences
  5125 (i.e. "=" on type bool) are handled, variable names of the form
  5126 "lit_<n>" are no longer reserved, significant speedup.
  5127 
  5128 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  5129 zChaff is still supported as well.
  5130 
  5131 * 'inductive' and 'datatype': provide projections of mutual rules,
  5132 bundled as foo_bar.inducts;
  5133 
  5134 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  5135 Library.
  5136 
  5137 * Library: moved theory Accessible_Part to main HOL.
  5138 
  5139 * Library: added theory Coinductive_List of potentially infinite lists
  5140 as greatest fixed-point.
  5141 
  5142 * Library: added theory AssocList which implements (finite) maps as
  5143 association lists.
  5144 
  5145 * Method "evaluation" solves goals (i.e. a boolean expression)
  5146 efficiently by compiling it to ML.  The goal is "proved" (via an
  5147 oracle) if it evaluates to True.
  5148 
  5149 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  5150 also when invoked by the simplifier.  This results in the Simplifier
  5151 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  5152 Configuration option fast_arith_split_limit=0 recovers the old
  5153 behavior.
  5154 
  5155 * Support for hex (0x20) and binary (0b1001) numerals.
  5156 
  5157 * New method: reify eqs (t), where eqs are equations for an
  5158 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  5159 parameter, computes a term s::'b and a list xs::'a list and proves the
  5160 theorem I xs s = t. This is also known as reification or quoting. The
  5161 resulting theorem is applied to the subgoal to substitute t with I xs
  5162 s.  If t is omitted, the subgoal itself is reified.
  5163 
  5164 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  5165 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  5166 where f is supposed to be a computable function (in the sense of code
  5167 generattion). The method uses reify to compute s and xs as above then
  5168 applies corr_thm and uses normalization by evaluation to "prove" f s =
  5169 r and finally gets the theorem t = r, which is again applied to the
  5170 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  5171 
  5172 * Reflection: Automatic reification now handels binding, an example is
  5173 available in src/HOL/ex/ReflectionEx.thy
  5174 
  5175 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  5176 command 'statespace' that is similar to 'record', but introduces an
  5177 abstract specification based on the locale infrastructure instead of
  5178 HOL types.  This leads to extra flexibility in composing state spaces,
  5179 in particular multiple inheritance and renaming of components.
  5180 
  5181 
  5182 *** HOL-Complex ***
  5183 
  5184 * Hyperreal: Functions root and sqrt are now defined on negative real
  5185 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  5186 Nonnegativity side conditions have been removed from many lemmas, so
  5187 that more subgoals may now be solved by simplification; potential
  5188 INCOMPATIBILITY.
  5189 
  5190 * Real: new type classes formalize real normed vector spaces and
  5191 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  5192 and norm :: 'a => real.
  5193 
  5194 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  5195 reals into other types. The overloaded constant Reals :: 'a set is now
  5196 defined as range of_real; potential INCOMPATIBILITY.
  5197 
  5198 * Real: proper support for ML code generation, including 'quickcheck'.
  5199 Reals are implemented as arbitrary precision rationals.
  5200 
  5201 * Hyperreal: Several constants that previously worked only for the
  5202 reals have been generalized, so they now work over arbitrary vector
  5203 spaces. Type annotations may need to be added in some cases; potential
  5204 INCOMPATIBILITY.
  5205 
  5206   Infinitesimal  :: ('a::real_normed_vector) star set
  5207   HFinite        :: ('a::real_normed_vector) star set
  5208   HInfinite      :: ('a::real_normed_vector) star set
  5209   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5210   monad          :: ('a::real_normed_vector) star => 'a star set
  5211   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5212   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5213   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5214   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5215   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5216   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5217   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5218   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5219   sgn            :: 'a::real_normed_vector => 'a
  5220   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5221 
  5222 * Complex: Some complex-specific constants are now abbreviations for
  5223 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5224 hnorm.  Other constants have been entirely removed in favor of the
  5225 polymorphic versions (INCOMPATIBILITY):
  5226 
  5227   approx        <-- capprox
  5228   HFinite       <-- CFinite
  5229   HInfinite     <-- CInfinite
  5230   Infinitesimal <-- CInfinitesimal
  5231   monad         <-- cmonad
  5232   galaxy        <-- cgalaxy
  5233   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5234   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5235   (ns)deriv     <-- (ns)cderiv
  5236 
  5237 
  5238 *** HOL-Algebra ***
  5239 
  5240 * Formalisation of ideals and the quotient construction over rings.
  5241 
  5242 * Order and lattice theory no longer based on records.
  5243 INCOMPATIBILITY.
  5244 
  5245 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5246 greatest_closed.  INCOMPATIBILITY.
  5247 
  5248 * Method algebra is now set up via an attribute.  For examples see
  5249 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5250 of algebraic structures.
  5251 
  5252 * Renamed theory CRing to Ring.
  5253 
  5254 
  5255 *** HOL-Nominal ***
  5256 
  5257 * Substantial, yet incomplete support for nominal datatypes (binding
  5258 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5259 src/HOL/Nominal/Examples.  Prospective users should consult
  5260 http://isabelle.in.tum.de/nominal/
  5261 
  5262 
  5263 *** ML ***
  5264 
  5265 * ML basics: just one true type int, which coincides with IntInf.int
  5266 (even on SML/NJ).
  5267 
  5268 * ML within Isar: antiquotations allow to embed statically-checked
  5269 formal entities in the source, referring to the context available at
  5270 compile-time.  For example:
  5271 
  5272 ML {* @{sort "{zero,one}"} *}
  5273 ML {* @{typ "'a => 'b"} *}
  5274 ML {* @{term "%x. x"} *}
  5275 ML {* @{prop "x == y"} *}
  5276 ML {* @{ctyp "'a => 'b"} *}
  5277 ML {* @{cterm "%x. x"} *}
  5278 ML {* @{cprop "x == y"} *}
  5279 ML {* @{thm asm_rl} *}
  5280 ML {* @{thms asm_rl} *}
  5281 ML {* @{type_name c} *}
  5282 ML {* @{type_syntax c} *}
  5283 ML {* @{const_name c} *}
  5284 ML {* @{const_syntax c} *}
  5285 ML {* @{context} *}
  5286 ML {* @{theory} *}
  5287 ML {* @{theory Pure} *}
  5288 ML {* @{theory_ref} *}
  5289 ML {* @{theory_ref Pure} *}
  5290 ML {* @{simpset} *}
  5291 ML {* @{claset} *}
  5292 ML {* @{clasimpset} *}
  5293 
  5294 The same works for sources being ``used'' within an Isar context.
  5295 
  5296 * ML in Isar: improved error reporting; extra verbosity with
  5297 ML_Context.trace enabled.
  5298 
  5299 * Pure/General/table.ML: the join operations now works via exceptions
  5300 DUP/SAME instead of type option. This is simpler in simple cases, and
  5301 admits slightly more efficient complex applications.
  5302 
  5303 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5304 use Context.generic instead of just theory.
  5305 
  5306 * Pure: datatype Context.generic joins theory/Proof.context and
  5307 provides some facilities for code that works in either kind of
  5308 context, notably GenericDataFun for uniform theory and proof data.
  5309 
  5310 * Pure: simplified internal attribute type, which is now always
  5311 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5312 local (Proof.context) attributes have been discontinued, while
  5313 minimizing code duplication. Thm.rule_attribute and
  5314 Thm.declaration_attribute build canonical attributes; see also structure
  5315 Context for further operations on Context.generic, notably
  5316 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5317 declarations and definitions.
  5318 
  5319 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5320 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5321 init only required for impure data. INCOMPATIBILITY: empty really need
  5322 to be empty (no dependencies on theory content!)
  5323 
  5324 * Pure/kernel: consts certification ignores sort constraints given in
  5325 signature declarations. (This information is not relevant to the
  5326 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5327 potential INCOMPATIBILITY.
  5328 
  5329 * Pure: axiomatic type classes are now purely definitional, with
  5330 explicit proofs of class axioms and super class relations performed
  5331 internally. See Pure/axclass.ML for the main internal interfaces --
  5332 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5333 AxClass.axiomatize_class/classrel/arity supersede
  5334 Sign.add_classes/classrel/arities.
  5335 
  5336 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5337 global/local versions on theory vs. Proof.context have been
  5338 discontinued; Attrib.syntax and Method.syntax have been adapted
  5339 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5340 attributes, methods, etc.
  5341 
  5342 * Pure: several functions of signature "... -> theory -> theory * ..."
  5343 have been reoriented to "... -> theory -> ... * theory" in order to
  5344 allow natural usage in combination with the ||>, ||>>, |-> and
  5345 fold_map combinators.
  5346 
  5347 * Pure: official theorem names (closed derivations) and additional
  5348 comments (tags) are now strictly separate.  Name hints -- which are
  5349 maintained as tags -- may be attached any time without affecting the
  5350 derivation.
  5351 
  5352 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5353 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5354 achieve the old behaviour.
  5355 
  5356 * Pure: the "Goal" constant is now called "prop", supporting a
  5357 slightly more general idea of ``protecting'' meta-level rule
  5358 statements.
  5359 
  5360 * Pure: Logic.(un)varify only works in a global context, which is now
  5361 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5362 Logic.legacy_(un)varify as temporary workaround.
  5363 
  5364 * Pure: structure Name provides scalable operations for generating
  5365 internal variable names, notably Name.variants etc.  This replaces
  5366 some popular functions from term.ML:
  5367 
  5368   Term.variant		->  Name.variant
  5369   Term.variantlist	->  Name.variant_list
  5370   Term.invent_names	->  Name.invent_list
  5371 
  5372 Note that low-level renaming rarely occurs in new code -- operations
  5373 from structure Variable are used instead (see below).
  5374 
  5375 * Pure: structure Variable provides fundamental operations for proper
  5376 treatment of fixed/schematic variables in a context.  For example,
  5377 Variable.import introduces fixes for schematics of given facts and
  5378 Variable.export reverses the effect (up to renaming) -- this replaces
  5379 various freeze_thaw operations.
  5380 
  5381 * Pure: structure Goal provides simple interfaces for
  5382 init/conclude/finish and tactical prove operations (replacing former
  5383 Tactic.prove).  Goal.prove is the canonical way to prove results
  5384 within a given context; Goal.prove_global is a degraded version for
  5385 theory level goals, including a global Drule.standard.  Note that
  5386 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5387 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5388 in a locale context).
  5389 
  5390 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5391 and type checking (Syntax.check_term etc.), with common combinations
  5392 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5393 which are considered legacy and await removal.
  5394 
  5395 * Pure/Syntax: generic interfaces for type unchecking
  5396 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5397 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5398 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5399 available for convenience, but refer to the very same operations using
  5400 a mere theory instead of a full context.
  5401 
  5402 * Isar: simplified treatment of user-level errors, using exception
  5403 ERROR of string uniformly.  Function error now merely raises ERROR,
  5404 without any side effect on output channels.  The Isar toplevel takes
  5405 care of proper display of ERROR exceptions.  ML code may use plain
  5406 handle/can/try; cat_error may be used to concatenate errors like this:
  5407 
  5408   ... handle ERROR msg => cat_error msg "..."
  5409 
  5410 Toplevel ML code (run directly or through the Isar toplevel) may be
  5411 embedded into the Isar toplevel with exception display/debug like
  5412 this:
  5413 
  5414   Isar.toplevel (fn () => ...)
  5415 
  5416 INCOMPATIBILITY, removed special transform_error facilities, removed
  5417 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5418 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5419 -- use plain ERROR instead.
  5420 
  5421 * Isar: theory setup now has type (theory -> theory), instead of a
  5422 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5423 
  5424 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5425 ProofContext.debug/verbose flags.
  5426 
  5427 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5428 theory before entering a proof state.  Transactions now always see a
  5429 quasi-functional intermediate checkpoint, both in interactive and
  5430 batch mode.
  5431 
  5432 * Isar: simplified interfaces for outer syntax.  Renamed
  5433 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5434 OuterSyntax.add_parsers -- this functionality is now included in
  5435 OuterSyntax.command etc.  INCOMPATIBILITY.
  5436 
  5437 * Simplifier: the simpset of a running simplification process now
  5438 contains a proof context (cf. Simplifier.the_context), which is the
  5439 very context that the initial simpset has been retrieved from (by
  5440 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5441 (solver, looper etc.) may depend on arbitrary proof data.
  5442 
  5443 * Simplifier.inherit_context inherits the proof context (plus the
  5444 local bounds) of the current simplification process; any simproc
  5445 etc. that calls the Simplifier recursively should do this!  Removed
  5446 former Simplifier.inherit_bounds, which is already included here --
  5447 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5448 specify an explicit context using Simplifier.context/theory_context.
  5449 
  5450 * Simplifier/Classical Reasoner: more abstract interfaces
  5451 change_simpset/claset for modifying the simpset/claset reference of a
  5452 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5453 INCOMPATIBILITY.
  5454 
  5455 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5456 "Trueprop" etc.
  5457 
  5458 
  5459 *** System ***
  5460 
  5461 * settings: the default heap location within ISABELLE_HOME_USER now
  5462 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5463 Isabelle installations.
  5464 
  5465 * isabelle-process: option -S (secure mode) disables some critical
  5466 operations, notably runtime compilation and evaluation of ML source
  5467 code.
  5468 
  5469 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5470 
  5471 * Support for parallel execution, using native multicore support of
  5472 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5473 independent theories, according to the given theory header
  5474 specifications. The maximum number of worker threads is specified via
  5475 usedir option -M or the "max-threads" setting in Proof General. A
  5476 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5477 to 6 on a 8-core machine.  User-code needs to observe certain
  5478 guidelines for thread-safe programming, see appendix A in the Isar
  5479 Implementation manual.
  5480 
  5481 
  5482 
  5483 New in Isabelle2005 (October 2005)
  5484 ----------------------------------
  5485 
  5486 *** General ***
  5487 
  5488 * Theory headers: the new header syntax for Isar theories is
  5489 
  5490   theory <name>
  5491   imports <theory1> ... <theoryN>
  5492   uses <file1> ... <fileM>
  5493   begin
  5494 
  5495 where the 'uses' part is optional.  The previous syntax
  5496 
  5497   theory <name> = <theory1> + ... + <theoryN>:
  5498 
  5499 will disappear in the next release.  Use isatool fixheaders to convert
  5500 existing theory files.  Note that there is no change in ancient
  5501 non-Isar theories now, but these will disappear soon.
  5502 
  5503 * Theory loader: parent theories can now also be referred to via
  5504 relative and absolute paths.
  5505 
  5506 * Command 'find_theorems' searches for a list of criteria instead of a
  5507 list of constants. Known criteria are: intro, elim, dest, name:string,
  5508 simp:term, and any term. Criteria can be preceded by '-' to select
  5509 theorems that do not match. Intro, elim, dest select theorems that
  5510 match the current goal, name:s selects theorems whose fully qualified
  5511 name contain s, and simp:term selects all simplification rules whose
  5512 lhs match term.  Any other term is interpreted as pattern and selects
  5513 all theorems matching the pattern. Available in ProofGeneral under
  5514 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5515 
  5516   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5517 
  5518 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5519 matching the current goal as introduction rule and not having "HOL."
  5520 in their name (i.e. not being defined in theory HOL).
  5521 
  5522 * Command 'thms_containing' has been discontinued in favour of
  5523 'find_theorems'; INCOMPATIBILITY.
  5524 
  5525 * Communication with Proof General is now 8bit clean, which means that
  5526 Unicode text in UTF-8 encoding may be used within theory texts (both
  5527 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5528 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5529 
  5530   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5531   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5532 
  5533 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5534 Classical Reasoner.  Typical big applications run around 2 times
  5535 faster.
  5536 
  5537 
  5538 *** Document preparation ***
  5539 
  5540 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5541 of raw sources.  Only those symbols that do not require additional
  5542 LaTeX packages (depending on comments in isabellesym.sty) are
  5543 displayed properly, everything else is left verbatim.  isatool display
  5544 and isatool print are used as front ends (these are subject to the
  5545 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5546 
  5547 * Command tags control specific markup of certain regions of text,
  5548 notably folding and hiding.  Predefined tags include "theory" (for
  5549 theory begin and end), "proof" for proof commands, and "ML" for
  5550 commands involving ML code; the additional tags "visible" and
  5551 "invisible" are unused by default.  Users may give explicit tag
  5552 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5553 interpretation of tags is determined by the LaTeX job during document
  5554 preparation: see option -V of isatool usedir, or options -n and -t of
  5555 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5556 \isadroptag.
  5557 
  5558 Several document versions may be produced at the same time via isatool
  5559 usedir (the generated index.html will link all of them).  Typical
  5560 specifications include ''-V document=theory,proof,ML'' to present
  5561 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5562 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5563 these parts without any formal replacement text.  The Isabelle site
  5564 default settings produce ''document'' and ''outline'' versions as
  5565 specified above.
  5566 
  5567 * Several new antiquotations:
  5568 
  5569   @{term_type term} prints a term with its type annotated;
  5570 
  5571   @{typeof term} prints the type of a term;
  5572 
  5573   @{const const} is the same as @{term const}, but checks that the
  5574   argument is a known logical constant;
  5575 
  5576   @{term_style style term} and @{thm_style style thm} print a term or
  5577   theorem applying a "style" to it
  5578 
  5579   @{ML text}
  5580 
  5581 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5582 definitions, equations, inequations etc., 'concl' printing only the
  5583 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5584 to print the specified premise.  TermStyle.add_style provides an ML
  5585 interface for introducing further styles.  See also the "LaTeX Sugar"
  5586 document practical applications.  The ML antiquotation prints
  5587 type-checked ML expressions verbatim.
  5588 
  5589 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5590 and 'text' support optional locale specification '(in loc)', which
  5591 specifies the default context for interpreting antiquotations.  For
  5592 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5593 
  5594 * Option 'locale=NAME' of antiquotations specifies an alternative
  5595 context interpreting the subsequent argument.  For example: @{thm
  5596 [locale=lattice] inf_assoc}.
  5597 
  5598 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5599 a proof context.
  5600 
  5601 * Proper output of antiquotations for theory commands involving a
  5602 proof context (such as 'locale' or 'theorem (in loc) ...').
  5603 
  5604 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5605 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5606 
  5607 * isatool usedir: new option -C (default true) controls whether option
  5608 -D should include a copy of the original document directory; -C false
  5609 prevents unwanted effects such as copying of administrative CVS data.
  5610 
  5611 
  5612 *** Pure ***
  5613 
  5614 * Considerably improved version of 'constdefs' command.  Now performs
  5615 automatic type-inference of declared constants; additional support for
  5616 local structure declarations (cf. locales and HOL records), see also
  5617 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5618 sequential dependencies of definitions within a single 'constdefs'
  5619 section; moreover, the declared name needs to be an identifier.  If
  5620 all fails, consider to fall back on 'consts' and 'defs' separately.
  5621 
  5622 * Improved indexed syntax and implicit structures.  First of all,
  5623 indexed syntax provides a notational device for subscripted
  5624 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5625 expressions.  Secondly, in a local context with structure
  5626 declarations, number indexes \<^sub>n or the empty index (default
  5627 number 1) refer to a certain fixed variable implicitly; option
  5628 show_structs controls printing of implicit structures.  Typical
  5629 applications of these concepts involve record types and locales.
  5630 
  5631 * New command 'no_syntax' removes grammar declarations (and
  5632 translations) resulting from the given syntax specification, which is
  5633 interpreted in the same manner as for the 'syntax' command.
  5634 
  5635 * 'Advanced' translation functions (parse_translation etc.) may depend
  5636 on the signature of the theory context being presently used for
  5637 parsing/printing, see also isar-ref manual.
  5638 
  5639 * Improved 'oracle' command provides a type-safe interface to turn an
  5640 ML expression of type theory -> T -> term into a primitive rule of
  5641 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5642 is already included here); see also FOL/ex/IffExample.thy;
  5643 INCOMPATIBILITY.
  5644 
  5645 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5646 before); "cI" is no longer bound, use "c.intro" instead.
  5647 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5648 axclasses vs. locales.
  5649 
  5650 * Improved internal renaming of symbolic identifiers -- attach primes
  5651 instead of base 26 numbers.
  5652 
  5653 * New flag show_question_marks controls printing of leading question
  5654 marks in schematic variable names.
  5655 
  5656 * In schematic variable names, *any* symbol following \<^isub> or
  5657 \<^isup> is now treated as part of the base name.  For example, the
  5658 following works without printing of awkward ".0" indexes:
  5659 
  5660   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5661     by simp
  5662 
  5663 * Inner syntax includes (*(*nested*) comments*).
  5664 
  5665 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5666 annotations as "(00...)".
  5667 
  5668 * Clear separation of logical types and nonterminals, where the latter
  5669 may only occur in 'syntax' specifications or type abbreviations.
  5670 Before that distinction was only partially implemented via type class
  5671 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5672 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5673 exotic syntax specifications may require further adaption
  5674 (e.g. Cube/Cube.thy).
  5675 
  5676 * Removed obsolete type class "logic", use the top sort {} instead.
  5677 Note that non-logical types should be declared as 'nonterminals'
  5678 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5679 specifications.
  5680 
  5681 * Attributes 'induct' and 'cases': type or set names may now be
  5682 locally fixed variables as well.
  5683 
  5684 * Simplifier: can now control the depth to which conditional rewriting
  5685 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5686 Limit.
  5687 
  5688 * Simplifier: simplification procedures may now take the current
  5689 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5690 interface), which is very useful for calling the Simplifier
  5691 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5692 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5693 low-level mk_simproc no longer applies Logic.varify internally, to
  5694 allow for use in a context of fixed variables.
  5695 
  5696 * thin_tac now works even if the assumption being deleted contains !!
  5697 or ==>.  More generally, erule now works even if the major premise of
  5698 the elimination rule contains !! or ==>.
  5699 
  5700 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5701 
  5702 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5703 from Pure, which contains all common declarations already.  Both
  5704 theories are defined via plain Isabelle/Isar .thy files.
  5705 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5706 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5707 use isatool fixcpure to adapt your theory and ML sources.
  5708 
  5709 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5710 selections of theorems in named facts via index ranges.
  5711 
  5712 * 'print_theorems': in theory mode, really print the difference
  5713 wrt. the last state (works for interactive theory development only),
  5714 in proof mode print all local facts (cf. 'print_facts');
  5715 
  5716 * 'hide': option '(open)' hides only base names.
  5717 
  5718 * More efficient treatment of intermediate checkpoints in interactive
  5719 theory development.
  5720 
  5721 * Code generator is now invoked via code_module (incremental code
  5722 generation) and code_library (modular code generation, ML structures
  5723 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5724 must be quoted when used as identifiers.
  5725 
  5726 * New 'value' command for reading, evaluating and printing terms using
  5727 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5728 quoted when used as identifier.
  5729 
  5730 
  5731 *** Locales ***
  5732 
  5733 * New commands for the interpretation of locale expressions in
  5734 theories (1), locales (2) and proof contexts (3).  These generate
  5735 proof obligations from the expression specification.  After the
  5736 obligations have been discharged, theorems of the expression are added
  5737 to the theory, target locale or proof context.  The synopsis of the
  5738 commands is a follows:
  5739 
  5740   (1) interpretation expr inst
  5741   (2) interpretation target < expr
  5742   (3) interpret expr inst
  5743 
  5744 Interpretation in theories and proof contexts require a parameter
  5745 instantiation of terms from the current context.  This is applied to
  5746 specifications and theorems of the interpreted expression.
  5747 Interpretation in locales only permits parameter renaming through the
  5748 locale expression.  Interpretation is smart in that interpretations
  5749 that are active already do not occur in proof obligations, neither are
  5750 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5751 inspect active interpretations of a particular locale.  For details,
  5752 see the Isar Reference manual.  Examples can be found in
  5753 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5754 
  5755 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5756 'interpret' instead.
  5757 
  5758 * New context element 'constrains' for adding type constraints to
  5759 parameters.
  5760 
  5761 * Context expressions: renaming of parameters with syntax
  5762 redeclaration.
  5763 
  5764 * Locale declaration: 'includes' disallowed.
  5765 
  5766 * Proper static binding of attribute syntax -- i.e. types / terms /
  5767 facts mentioned as arguments are always those of the locale definition
  5768 context, independently of the context of later invocations.  Moreover,
  5769 locale operations (renaming and type / term instantiation) are applied
  5770 to attribute arguments as expected.
  5771 
  5772 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5773 actual attributes; rare situations may require Attrib.attribute to
  5774 embed those attributes into Attrib.src that lack concrete syntax.
  5775 Attribute implementations need to cooperate properly with the static
  5776 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5777 Attrib.XXX_thm etc. already do the right thing without further
  5778 intervention.  Only unusual applications -- such as "where" or "of"
  5779 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5780 on the context and the facts involved -- may have to assign parsed
  5781 values to argument tokens explicitly.
  5782 
  5783 * Changed parameter management in theorem generation for long goal
  5784 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5785 theorem statement in rare situations.
  5786 
  5787 * Locale inspection command 'print_locale' omits notes elements.  Use
  5788 'print_locale!' to have them included in the output.
  5789 
  5790 
  5791 *** Provers ***
  5792 
  5793 * Provers/hypsubst.ML: improved version of the subst method, for
  5794 single-step rewriting: it now works in bound variable contexts. New is
  5795 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5796 rewrite a different subterm than the original subst method, which is
  5797 still available as 'simplesubst'.
  5798 
  5799 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5800 and quasi orders.
  5801 
  5802 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5803 reflexive-transitive closure of relations.
  5804 
  5805 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5806 limit (previously hard-coded with a value of 20) user-definable.
  5807 
  5808 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5809 is peformed already.  Object-logics merely need to finish their
  5810 initial simpset configuration as before.  INCOMPATIBILITY.
  5811 
  5812 
  5813 *** HOL ***
  5814 
  5815 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5816 
  5817   syntax (epsilon)
  5818     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5819 
  5820 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5821 and x-symbol; use option '-m epsilon' to get it actually printed.
  5822 Moreover, the mathematically important symbolic identifier \<epsilon>
  5823 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5824 
  5825 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5826 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5827 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5828 support corresponding Isar calculations.
  5829 
  5830 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5831 instead of ":".
  5832 
  5833 * theory SetInterval: changed the syntax for open intervals:
  5834 
  5835   Old       New
  5836   {..n(}    {..<n}
  5837   {)n..}    {n<..}
  5838   {m..n(}   {m..<n}
  5839   {)m..n}   {m<..n}
  5840   {)m..n(}  {m<..<n}
  5841 
  5842 The old syntax is still supported but will disappear in the next
  5843 release.  For conversion use the following Emacs search and replace
  5844 patterns (these are not perfect but work quite well):
  5845 
  5846   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5847   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5848 
  5849 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5850 equalities in commutative rings; method 'algebra' provides a generic
  5851 interface.
  5852 
  5853 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5854 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5855 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5856 be a tuple pattern.
  5857 
  5858 Some new syntax forms are available:
  5859 
  5860   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5861   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5862   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5863   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5864 
  5865 The latter form "\<Sum>x < k. e" used to be based on a separate
  5866 function "Summation", which has been discontinued.
  5867 
  5868 * theory Finite_Set: in structured induction proofs, the insert case
  5869 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5870 (insert F x)'.
  5871 
  5872 * The 'refute' command has been extended to support a much larger
  5873 fragment of HOL, including axiomatic type classes, constdefs and
  5874 typedefs, inductive datatypes and recursion.
  5875 
  5876 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5877 Requires zChaff with proof generation to be installed.  See
  5878 HOL/ex/SAT_Examples.thy for examples.
  5879 
  5880 * Datatype induction via method 'induct' now preserves the name of the
  5881 induction variable. For example, when proving P(xs::'a list) by
  5882 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5883 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5884 in unstructured proof scripts.
  5885 
  5886 * Reworked implementation of records.  Improved scalability for
  5887 records with many fields, avoiding performance problems for type
  5888 inference. Records are no longer composed of nested field types, but
  5889 of nested extension types. Therefore the record type only grows linear
  5890 in the number of extensions and not in the number of fields.  The
  5891 top-level (users) view on records is preserved.  Potential
  5892 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5893 old record representation. The type generated for a record is called
  5894 <record_name>_ext_type.
  5895 
  5896 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5897 proofs triggered by a record definition or a simproc (if
  5898 quick_and_dirty is enabled).  Definitions of large records can take
  5899 quite long.
  5900 
  5901 New simproc record_upd_simproc for simplification of multiple record
  5902 updates enabled by default.  Moreover, trivial updates are also
  5903 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5904 occasionally, since simplification is more powerful by default.
  5905 
  5906 * typedef: proper support for polymorphic sets, which contain extra
  5907 type-variables in the term.
  5908 
  5909 * Simplifier: automatically reasons about transitivity chains
  5910 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5911 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5912 old proofs break occasionally as simplification may now solve more
  5913 goals than previously.
  5914 
  5915 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5916 present.  Works for all partial orders (class "order"), in particular
  5917 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5918 just like y <= x.
  5919 
  5920 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5921 bound variable or a constant then the let is unfolded.  Otherwise
  5922 first a is simplified to b, and then f b is simplified to g. If
  5923 possible we abstract b from g arriving at "let x = b in h x",
  5924 otherwise we unfold the let and arrive at g.  The simproc can be
  5925 enabled/disabled by the reference use_let_simproc.  Potential
  5926 INCOMPATIBILITY since simplification is more powerful by default.
  5927 
  5928 * Classical reasoning: the meson method now accepts theorems as arguments.
  5929 
  5930 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5931 jobs to provide advice on the provability of subgoals.
  5932 
  5933 * Theory OrderedGroup and Ring_and_Field: various additions and
  5934 improvements to faciliate calculations involving equalities and
  5935 inequalities.
  5936 
  5937 The following theorems have been eliminated or modified
  5938 (INCOMPATIBILITY):
  5939 
  5940   abs_eq             now named abs_of_nonneg
  5941   abs_of_ge_0        now named abs_of_nonneg
  5942   abs_minus_eq       now named abs_of_nonpos
  5943   imp_abs_id         now named abs_of_nonneg
  5944   imp_abs_neg_id     now named abs_of_nonpos
  5945   mult_pos           now named mult_pos_pos
  5946   mult_pos_le        now named mult_nonneg_nonneg
  5947   mult_pos_neg_le    now named mult_nonneg_nonpos
  5948   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5949   mult_neg           now named mult_neg_neg
  5950   mult_neg_le        now named mult_nonpos_nonpos
  5951 
  5952 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5953      
  5954      zero_le_square
  5955      not_square_less_zero 
  5956 
  5957   The following lemmas have been deleted from Real/RealPow:
  5958   
  5959      realpow_zero_zero
  5960      realpow_two
  5961      realpow_less
  5962      zero_le_power
  5963      realpow_two_le
  5964      abs_realpow_two
  5965      realpow_two_abs     
  5966 
  5967 * Theory Parity: added rules for simplifying exponents.
  5968 
  5969 * Theory List:
  5970 
  5971 The following theorems have been eliminated or modified
  5972 (INCOMPATIBILITY):
  5973 
  5974   list_all_Nil       now named list_all.simps(1)
  5975   list_all_Cons      now named list_all.simps(2)
  5976   list_all_conv      now named list_all_iff
  5977   set_mem_eq         now named mem_iff
  5978 
  5979 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5980 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5981 
  5982 
  5983 *** HOL-Complex ***
  5984 
  5985 * Theory RealDef: better support for embedding natural numbers and
  5986 integers in the reals.
  5987 
  5988 The following theorems have been eliminated or modified
  5989 (INCOMPATIBILITY):
  5990 
  5991   exp_ge_add_one_self  now requires no hypotheses
  5992   real_of_int_add      reversed direction of equality (use [symmetric])
  5993   real_of_int_minus    reversed direction of equality (use [symmetric])
  5994   real_of_int_diff     reversed direction of equality (use [symmetric])
  5995   real_of_int_mult     reversed direction of equality (use [symmetric])
  5996 
  5997 * Theory RComplete: expanded support for floor and ceiling functions.
  5998 
  5999 * Theory Ln is new, with properties of the natural logarithm
  6000 
  6001 * Hyperreal: There is a new type constructor "star" for making
  6002 nonstandard types.  The old type names are now type synonyms:
  6003 
  6004   hypreal = real star
  6005   hypnat = nat star
  6006   hcomplex = complex star
  6007 
  6008 * Hyperreal: Many groups of similarly-defined constants have been
  6009 replaced by polymorphic versions (INCOMPATIBILITY):
  6010 
  6011   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  6012 
  6013   starset      <-- starsetNat, starsetC
  6014   *s*          <-- *sNat*, *sc*
  6015   starset_n    <-- starsetNat_n, starsetC_n
  6016   *sn*         <-- *sNatn*, *scn*
  6017   InternalSets <-- InternalNatSets, InternalCSets
  6018 
  6019   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  6020   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  6021   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  6022   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  6023   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  6024 
  6025 * Hyperreal: Many type-specific theorems have been removed in favor of
  6026 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  6027 
  6028   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  6029   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  6030   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  6031   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  6032   right_minus <-- hypreal_add_minus
  6033   left_minus <-- {hypreal,hcomplex}_add_minus_left
  6034   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  6035   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  6036   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  6037   mult_1_right <-- hcomplex_mult_one_right
  6038   mult_zero_left <-- hcomplex_mult_zero_left
  6039   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  6040   right_distrib <-- hypnat_add_mult_distrib2
  6041   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  6042   right_inverse <-- hypreal_mult_inverse
  6043   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  6044   order_refl <-- {hypreal,hypnat}_le_refl
  6045   order_trans <-- {hypreal,hypnat}_le_trans
  6046   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  6047   order_less_le <-- {hypreal,hypnat}_less_le
  6048   linorder_linear <-- {hypreal,hypnat}_le_linear
  6049   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  6050   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  6051   add_nonneg_nonneg <-- hypreal_le_add_order
  6052 
  6053 * Hyperreal: Separate theorems having to do with type-specific
  6054 versions of constants have been merged into theorems that apply to the
  6055 new polymorphic constants (INCOMPATIBILITY):
  6056 
  6057   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  6058   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  6059   STAR_Un <-- {STAR,NatStar,STARC}_Un
  6060   STAR_Int <-- {STAR,NatStar,STARC}_Int
  6061   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  6062   STAR_subset <-- {STAR,NatStar,STARC}_subset
  6063   STAR_mem <-- {STAR,NatStar,STARC}_mem
  6064   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  6065   STAR_diff <-- {STAR,STARC}_diff
  6066   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  6067     STARC_hcomplex_of_complex}_image_subset
  6068   starset_n_Un <-- starset{Nat,C}_n_Un
  6069   starset_n_Int <-- starset{Nat,C}_n_Int
  6070   starset_n_Compl <-- starset{Nat,C}_n_Compl
  6071   starset_n_diff <-- starset{Nat,C}_n_diff
  6072   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  6073   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  6074   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  6075   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  6076   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  6077   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  6078   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  6079   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  6080   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  6081   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  6082   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  6083   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  6084   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  6085   starfun_diff <-- starfun{C,RC,CR}_diff
  6086   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  6087   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  6088   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  6089   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  6090   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  6091   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  6092   starfun_Id <-- starfunC_Id
  6093   starfun_approx <-- starfun{Nat,CR}_approx
  6094   starfun_capprox <-- starfun{C,RC}_capprox
  6095   starfun_abs <-- starfunNat_rabs
  6096   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  6097   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  6098   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  6099   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  6100   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  6101   starfun_add_approx <-- starfunCR_add_approx
  6102   starfun_inverse_inverse <-- starfunC_inverse_inverse
  6103   starfun_divide <-- starfun{C,CR,RC}_divide
  6104   starfun_n <-- starfun{Nat,C}_n
  6105   starfun_n_mult <-- starfun{Nat,C}_n_mult
  6106   starfun_n_add <-- starfun{Nat,C}_n_add
  6107   starfun_n_add_minus <-- starfunNat_n_add_minus
  6108   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  6109   starfun_n_minus <-- starfun{Nat,C}_n_minus
  6110   starfun_n_eq <-- starfun{Nat,C}_n_eq
  6111 
  6112   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  6113   star_n_minus <-- {hypreal,hcomplex}_minus
  6114   star_n_diff <-- {hypreal,hcomplex}_diff
  6115   star_n_mult <-- {hypreal,hcomplex}_mult
  6116   star_n_inverse <-- {hypreal,hcomplex}_inverse
  6117   star_n_le <-- {hypreal,hypnat}_le
  6118   star_n_less <-- {hypreal,hypnat}_less
  6119   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  6120   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  6121   star_n_abs <-- hypreal_hrabs
  6122   star_n_divide <-- hcomplex_divide
  6123 
  6124   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  6125   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  6126   star_of_diff <-- hypreal_of_real_diff
  6127   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  6128   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  6129   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  6130   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  6131   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  6132   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  6133   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  6134   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  6135   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  6136   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  6137   star_of_number_of <-- {hypreal,hcomplex}_number_of
  6138   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  6139   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  6140   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  6141   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  6142   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  6143   star_of_power <-- hypreal_of_real_power
  6144   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  6145 
  6146 * Hyperreal: new method "transfer" that implements the transfer
  6147 principle of nonstandard analysis. With a subgoal that mentions
  6148 nonstandard types like "'a star", the command "apply transfer"
  6149 replaces it with an equivalent one that mentions only standard types.
  6150 To be successful, all free variables must have standard types; non-
  6151 standard variables must have explicit universal quantifiers.
  6152 
  6153 * Hyperreal: A theory of Taylor series.
  6154 
  6155 
  6156 *** HOLCF ***
  6157 
  6158 * Discontinued special version of 'constdefs' (which used to support
  6159 continuous functions) in favor of the general Pure one with full
  6160 type-inference.
  6161 
  6162 * New simplification procedure for solving continuity conditions; it
  6163 is much faster on terms with many nested lambda abstractions (cubic
  6164 instead of exponential time).
  6165 
  6166 * New syntax for domain package: selector names are now optional.
  6167 Parentheses should be omitted unless argument is lazy, for example:
  6168 
  6169   domain 'a stream = cons "'a" (lazy "'a stream")
  6170 
  6171 * New command 'fixrec' for defining recursive functions with pattern
  6172 matching; defining multiple functions with mutual recursion is also
  6173 supported.  Patterns may include the constants cpair, spair, up, sinl,
  6174 sinr, or any data constructor defined by the domain package. The given
  6175 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  6176 syntax and examples.
  6177 
  6178 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  6179 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  6180 but the proof obligation additionally includes an admissibility
  6181 requirement. The packages generate instances of class cpo or pcpo,
  6182 with continuity and strictness theorems for Rep and Abs.
  6183 
  6184 * HOLCF: Many theorems have been renamed according to a more standard naming
  6185 scheme (INCOMPATIBILITY):
  6186 
  6187   foo_inject:  "foo$x = foo$y ==> x = y"
  6188   foo_eq:      "(foo$x = foo$y) = (x = y)"
  6189   foo_less:    "(foo$x << foo$y) = (x << y)"
  6190   foo_strict:  "foo$UU = UU"
  6191   foo_defined: "... ==> foo$x ~= UU"
  6192   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  6193 
  6194 
  6195 *** ZF ***
  6196 
  6197 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  6198 including the First Isomorphism Theorem (on quotienting by the kernel
  6199 of a homomorphism).
  6200 
  6201 * ZF/Simplifier: install second copy of type solver that actually
  6202 makes use of TC rules declared to Isar proof contexts (or locales);
  6203 the old version is still required for ML proof scripts.
  6204 
  6205 
  6206 *** Cube ***
  6207 
  6208 * Converted to Isar theory format; use locales instead of axiomatic
  6209 theories.
  6210 
  6211 
  6212 *** ML ***
  6213 
  6214 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6215 for ||>, ||>>, |>>,
  6216 
  6217 * Pure/library.ML no longer defines its own option datatype, but uses
  6218 that of the SML basis, which has constructors NONE and SOME instead of
  6219 None and Some, as well as exception Option.Option instead of OPTION.
  6220 The functions the, if_none, is_some, is_none have been adapted
  6221 accordingly, while Option.map replaces apsome.
  6222 
  6223 * Pure/library.ML: the exception LIST has been given up in favour of
  6224 the standard exceptions Empty and Subscript, as well as
  6225 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6226 superceded by the standard hd and tl functions etc.
  6227 
  6228 A number of basic list functions are no longer exported to the ML
  6229 toplevel, as they are variants of predefined functions.  The following
  6230 suggests how one can translate existing code:
  6231 
  6232     rev_append xs ys = List.revAppend (xs, ys)
  6233     nth_elem (i, xs) = List.nth (xs, i)
  6234     last_elem xs = List.last xs
  6235     flat xss = List.concat xss
  6236     seq fs = List.app fs
  6237     partition P xs = List.partition P xs
  6238     mapfilter f xs = List.mapPartial f xs
  6239 
  6240 * Pure/library.ML: several combinators for linear functional
  6241 transformations, notably reverse application and composition:
  6242 
  6243   x |> f                f #> g
  6244   (x, y) |-> f          f #-> g
  6245 
  6246 * Pure/library.ML: introduced/changed precedence of infix operators:
  6247 
  6248   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6249   infix 2 ?;
  6250   infix 3 o oo ooo oooo;
  6251   infix 4 ~~ upto downto;
  6252 
  6253 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6254 infix operators.
  6255 
  6256 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6257 fold_map support linear functional transformations and nesting.  For
  6258 example:
  6259 
  6260   fold f [x1, ..., xN] y =
  6261     y |> f x1 |> ... |> f xN
  6262 
  6263   (fold o fold) f [xs1, ..., xsN] y =
  6264     y |> fold f xs1 |> ... |> fold f xsN
  6265 
  6266   fold f [x1, ..., xN] =
  6267     f x1 #> ... #> f xN
  6268 
  6269   (fold o fold) f [xs1, ..., xsN] =
  6270     fold f xs1 #> ... #> fold f xsN
  6271 
  6272 * Pure/library.ML: the following selectors on type 'a option are
  6273 available:
  6274 
  6275   the:               'a option -> 'a  (*partial*)
  6276   these:             'a option -> 'a  where 'a = 'b list
  6277   the_default: 'a -> 'a option -> 'a
  6278   the_list:          'a option -> 'a list
  6279 
  6280 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6281 basic operations for association lists, following natural argument
  6282 order; moreover the explicit equality predicate passed here avoids
  6283 potentially expensive polymorphic runtime equality checks.
  6284 The old functions may be expressed as follows:
  6285 
  6286   assoc = uncurry (AList.lookup (op =))
  6287   assocs = these oo AList.lookup (op =)
  6288   overwrite = uncurry (AList.update (op =)) o swap
  6289 
  6290 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6291 
  6292   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6293   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6294 
  6295 replacing make_keylist and keyfilter (occassionally used)
  6296 Naive rewrites:
  6297 
  6298   make_keylist = AList.make
  6299   keyfilter = AList.find (op =)
  6300 
  6301 * eq_fst and eq_snd now take explicit equality parameter, thus
  6302   avoiding eqtypes. Naive rewrites:
  6303 
  6304     eq_fst = eq_fst (op =)
  6305     eq_snd = eq_snd (op =)
  6306 
  6307 * Removed deprecated apl and apr (rarely used).
  6308   Naive rewrites:
  6309 
  6310     apl (n, op) =>>= curry op n
  6311     apr (op, m) =>>= fn n => op (n, m)
  6312 
  6313 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6314 provides a reasonably efficient light-weight implementation of sets as
  6315 lists.
  6316 
  6317 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6318 few new operations; existing lookup and update are now curried to
  6319 follow natural argument order (for use with fold etc.);
  6320 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6321 
  6322 * Pure/General: output via the Isabelle channels of
  6323 writeln/warning/error etc. is now passed through Output.output, with a
  6324 hook for arbitrary transformations depending on the print_mode
  6325 (cf. Output.add_mode -- the first active mode that provides a output
  6326 function wins).  Already formatted output may be embedded into further
  6327 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6328 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6329 accommodate easy composition of diagnostic messages etc.  Programmers
  6330 rarely need to care about Output.output or Output.raw at all, with
  6331 some notable exceptions: Output.output is required when bypassing the
  6332 standard channels (writeln etc.), or in token translations to produce
  6333 properly formatted results; Output.raw is required when capturing
  6334 already output material that will eventually be presented to the user
  6335 a second time.  For the default print mode, both Output.output and
  6336 Output.raw have no effect.
  6337 
  6338 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6339 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6340 cumulative results are displayed at the end of a batch session.
  6341 
  6342 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6343 replaced by File.platform_path and File.shell_path (with appropriate
  6344 hooks).  This provides a clean interface for unusual systems where the
  6345 internal and external process view of file names are different.
  6346 
  6347 * Pure: more efficient orders for basic syntactic entities: added
  6348 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6349 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6350 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6351 orders now -- potential INCOMPATIBILITY for code that depends on a
  6352 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6353 Library.sort_strings on result).
  6354 
  6355 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6356 fold_types traverse types/terms from left to right, observing natural
  6357 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6358 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6359 
  6360 * Pure: name spaces have been refined, with significant changes of the
  6361 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6362 to extern(_table).  The plain name entry path is superceded by a
  6363 general 'naming' context, which also includes the 'policy' to produce
  6364 a fully qualified name and external accesses of a fully qualified
  6365 name; NameSpace.extend is superceded by context dependent
  6366 Sign.declare_name.  Several theory and proof context operations modify
  6367 the naming context.  Especially note Theory.restore_naming and
  6368 ProofContext.restore_naming to get back to a sane state; note that
  6369 Theory.add_path is no longer sufficient to recover from
  6370 Theory.absolute_path in particular.
  6371 
  6372 * Pure: new flags short_names (default false) and unique_names
  6373 (default true) for controlling output of qualified names.  If
  6374 short_names is set, names are printed unqualified.  If unique_names is
  6375 reset, the name prefix is reduced to the minimum required to achieve
  6376 the original result when interning again, even if there is an overlap
  6377 with earlier declarations.
  6378 
  6379 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6380 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6381 (useful for printing error messages).  INCOMPATIBILITY.
  6382 
  6383 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6384 Theory.theory are now identified, referring to the universal
  6385 Context.theory (see Pure/context.ML).  Actual signature and theory
  6386 content is managed as theory data.  The old code and interfaces were
  6387 spread over many files and structures; the new arrangement introduces
  6388 considerable INCOMPATIBILITY to gain more clarity:
  6389 
  6390   Context -- theory management operations (name, identity, inclusion,
  6391     parents, ancestors, merge, etc.), plus generic theory data;
  6392 
  6393   Sign -- logical signature and syntax operations (declaring consts,
  6394     types, etc.), plus certify/read for common entities;
  6395 
  6396   Theory -- logical theory operations (stating axioms, definitions,
  6397     oracles), plus a copy of logical signature operations (consts,
  6398     types, etc.); also a few basic management operations (Theory.copy,
  6399     Theory.merge, etc.)
  6400 
  6401 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6402 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6403 for convenience -- they merely return the theory.
  6404 
  6405 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6406 
  6407 * Pure: the Isar proof context type is already defined early in Pure
  6408 as Context.proof (note that ProofContext.context and Proof.context are
  6409 aliases, where the latter is the preferred name).  This enables other
  6410 Isabelle components to refer to that type even before Isar is present.
  6411 
  6412 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6413 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6414 any of these kinds.  For example, Sign.intern typeK is now
  6415 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6416 Theory.hide_types.  Also note that former
  6417 Theory.hide_classes/types/consts are now
  6418 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6419 internalize their arguments!  INCOMPATIBILITY.
  6420 
  6421 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6422 datatype thmref (with constructors Name and NameSelection) instead of
  6423 plain string -- INCOMPATIBILITY;
  6424 
  6425 * Pure: cases produced by proof methods specify options, where NONE
  6426 means to remove case bindings -- INCOMPATIBILITY in
  6427 (RAW_)METHOD_CASES.
  6428 
  6429 * Pure: the following operations retrieve axioms or theorems from a
  6430 theory node or theory hierarchy, respectively:
  6431 
  6432   Theory.axioms_of: theory -> (string * term) list
  6433   Theory.all_axioms_of: theory -> (string * term) list
  6434   PureThy.thms_of: theory -> (string * thm) list
  6435   PureThy.all_thms_of: theory -> (string * thm) list
  6436 
  6437 * Pure: print_tac now outputs the goal through the trace channel.
  6438 
  6439 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6440 Reference Toplevel.debug (default false) controls detailed printing
  6441 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6442 controls execution profiling -- set to 1 for time and 2 for space
  6443 (both increase the runtime).
  6444 
  6445 * Isar session: The initial use of ROOT.ML is now always timed,
  6446 i.e. the log will show the actual process times, in contrast to the
  6447 elapsed wall-clock time that the outer shell wrapper produces.
  6448 
  6449 * Simplifier: improved handling of bound variables (nameless
  6450 representation, avoid allocating new strings).  Simprocs that invoke
  6451 the Simplifier recursively should use Simplifier.inherit_bounds to
  6452 avoid local name clashes.  Failure to do so produces warnings
  6453 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6454 for further details.
  6455 
  6456 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6457 bindings for all theorems stored within a given theory; this may help
  6458 in porting non-Isar theories to Isar ones, while keeping ML proof
  6459 scripts for the time being.
  6460 
  6461 * ML operator HTML.with_charset specifies the charset begin used for
  6462 generated HTML files.  For example:
  6463 
  6464   HTML.with_charset "utf-8" use_thy "Hebrew";
  6465   HTML.with_charset "utf-8" use_thy "Chinese";
  6466 
  6467 
  6468 *** System ***
  6469 
  6470 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6471 isabelle, isatool etc.).
  6472 
  6473 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6474 isatool doc, isatool mkdir, display_drafts etc.).
  6475 
  6476 * isatool usedir: option -f allows specification of the ML file to be
  6477 used by Isabelle; default is ROOT.ML.
  6478 
  6479 * New isatool version outputs the version identifier of the Isabelle
  6480 distribution being used.
  6481 
  6482 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6483 (containing Boolean satisfiability problems) into Isabelle/HOL
  6484 theories.
  6485 
  6486 
  6487 
  6488 New in Isabelle2004 (April 2004)
  6489 --------------------------------
  6490 
  6491 *** General ***
  6492 
  6493 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6494   Replaces linorder.ML.
  6495 
  6496 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6497   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6498   (\<a>...\<z>), are now considered normal letters, and can therefore
  6499   be used anywhere where an ASCII letter (a...zA...Z) has until
  6500   now. COMPATIBILITY: This obviously changes the parsing of some
  6501   terms, especially where a symbol has been used as a binder, say
  6502   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6503   as an identifier.  Fix it by inserting a space around former
  6504   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6505   existing theory and ML files.
  6506 
  6507 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6508 
  6509 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6510   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6511   a normal (but invisible) letter. For multiple letter subscripts repeat
  6512   \<^isub> like this: x\<^isub>1\<^isub>2.
  6513 
  6514 * Pure: There are now sub-/superscripts that can span more than one
  6515   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6516   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6517   superscript. The new control characters are not identifier parts.
  6518 
  6519 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6520   content of "..." to the latex file instead of \isacntrl... . The "..."
  6521   may consist of any printable characters excluding the end bracket >.
  6522 
  6523 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6524   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6525   declare constants "final", which prevents their being given a definition
  6526   later.  It is useful for constants whose behaviour is fixed axiomatically
  6527   rather than definitionally, such as the meta-logic connectives.
  6528 
  6529 * Pure: 'instance' now handles general arities with general sorts
  6530   (i.e. intersections of classes),
  6531 
  6532 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6533   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6534   It can be changed to alter the colors/layout of generated pages.
  6535 
  6536 
  6537 *** Isar ***
  6538 
  6539 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6540   cut_tac, subgoal_tac and thin_tac:
  6541   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6542     locales are no longer forced to write Isar proof scripts.
  6543     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6544     emulations.
  6545   - INCOMPATIBILITY: names of variables to be instantiated may no
  6546     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6547     This is consistent with the instantiation attribute "where".
  6548 
  6549 * Attributes "where" and "of":
  6550   - Now take type variables of instantiated theorem into account when reading
  6551     the instantiation string.  This fixes a bug that caused instantiated
  6552     theorems to have too special types in some circumstances.
  6553   - "where" permits explicit instantiations of type variables.
  6554 
  6555 * Calculation commands "moreover" and "also" no longer interfere with
  6556   current facts ("this"), admitting arbitrary combinations with "then"
  6557   and derived forms.
  6558 
  6559 * Locales:
  6560   - Goal statements involving the context element "includes" no longer
  6561     generate theorems with internal delta predicates (those ending on
  6562     "_axioms") in the premise.
  6563     Resolve particular premise with <locale>.intro to obtain old form.
  6564   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6565     specification and "includes" elements in goal statement.
  6566   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6567     [intro?] and [elim?] (respectively) by default.
  6568   - Experimental command for instantiation of locales in proof contexts:
  6569         instantiate <label>[<attrs>]: <loc>
  6570     Instantiates locale <loc> and adds all its theorems to the current context
  6571     taking into account their attributes.  Label and attrs are optional
  6572     modifiers, like in theorem declarations.  If present, names of
  6573     instantiated theorems are qualified with <label>, and the attributes
  6574     <attrs> are applied after any attributes these theorems might have already.
  6575       If the locale has assumptions, a chained fact of the form
  6576     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6577     are derived.  The command does not support old-style locales declared
  6578     with "locale (open)".
  6579       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6580 
  6581 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6582   (Isar) contexts.
  6583 
  6584 
  6585 *** HOL ***
  6586 
  6587 * Proof import: new image HOL4 contains the imported library from
  6588   the HOL4 system with about 2500 theorems. It is imported by
  6589   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6590   can be used like any other Isabelle image.  See
  6591   HOL/Import/HOL/README for more information.
  6592 
  6593 * Simplifier:
  6594   - Much improved handling of linear and partial orders.
  6595     Reasoners for linear and partial orders are set up for type classes
  6596     "linorder" and "order" respectively, and are added to the default simpset
  6597     as solvers.  This means that the simplifier can build transitivity chains
  6598     to solve goals from the assumptions.
  6599   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6600     of blast or auto after simplification become unnecessary because the goal
  6601     is solved by simplification already.
  6602 
  6603 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6604     all proved in axiomatic type classes for semirings, rings and fields.
  6605 
  6606 * Numerics:
  6607   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6608     now formalized using the Ring_and_Field theory mentioned above.
  6609   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6610     than before, because now they are set up once in a generic manner.
  6611   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6612     Look for the general versions in Ring_and_Field (and Power if they concern
  6613     exponentiation).
  6614 
  6615 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6616 
  6617 * Records:
  6618   - Record types are now by default printed with their type abbreviation
  6619     instead of the list of all field types. This can be configured via
  6620     the reference "print_record_type_abbr".
  6621   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6622     (not enabled by default).
  6623   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6624     EX x. x = sel r to True (not enabled by default).
  6625   - Tactic "record_split_simp_tac" to split and simplify records added.
  6626 
  6627 * 'specification' command added, allowing for definition by
  6628   specification.  There is also an 'ax_specification' command that
  6629   introduces the new constants axiomatically.
  6630 
  6631 * arith(_tac) is now able to generate counterexamples for reals as well.
  6632 
  6633 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6634 
  6635 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6636   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6637 
  6638 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6639   matrix theory to linear programming.
  6640 
  6641 * Unions and Intersections:
  6642   The latex output syntax of UN and INT has been changed
  6643   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6644   i.e. the index formulae has become a subscript.
  6645   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6646 
  6647 * Unions and Intersections over Intervals:
  6648   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6649   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6650   like in normal math, and corresponding versions for < and for intersection.
  6651 
  6652 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6653   lexicographic dictonary ordering has been added as "lexord".
  6654 
  6655 * ML: the legacy theory structures Int and List have been removed. They had
  6656   conflicted with ML Basis Library structures having the same names.
  6657 
  6658 * 'refute' command added to search for (finite) countermodels.  Only works
  6659   for a fragment of HOL.  The installation of an external SAT solver is
  6660   highly recommended.  See "HOL/Refute.thy" for details.
  6661 
  6662 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6663   formulae under an assignment of free variables to random values.
  6664   In contrast to 'refute', it can deal with inductive datatypes,
  6665   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6666   for examples.
  6667 
  6668 
  6669 *** HOLCF ***
  6670 
  6671 * Streams now come with concatenation and are part of the HOLCF image
  6672 
  6673 
  6674 
  6675 New in Isabelle2003 (May 2003)
  6676 ------------------------------
  6677 
  6678 *** General ***
  6679 
  6680 * Provers/simplifier:
  6681 
  6682   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6683     Assumptions are now subject to complete mutual simplification,
  6684     not just from left to right. The simplifier now preserves
  6685     the order of assumptions.
  6686 
  6687     Potential INCOMPATIBILITY:
  6688 
  6689     -- simp sometimes diverges where the old version did
  6690        not, e.g. invoking simp on the goal
  6691 
  6692         [| P (f x); y = x; f x = f y |] ==> Q
  6693 
  6694        now gives rise to the infinite reduction sequence
  6695 
  6696         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6697 
  6698        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6699        kind of problem.
  6700 
  6701     -- Tactics combining classical reasoner and simplification (such as auto)
  6702        are also affected by this change, because many of them rely on
  6703        simp. They may sometimes diverge as well or yield a different numbers
  6704        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6705        in case of problems. Sometimes subsequent calls to the classical
  6706        reasoner will fail because a preceeding call to the simplifier too
  6707        eagerly simplified the goal, e.g. deleted redundant premises.
  6708 
  6709   - The simplifier trace now shows the names of the applied rewrite rules
  6710 
  6711   - You can limit the number of recursive invocations of the simplifier
  6712     during conditional rewriting (where the simplifie tries to solve the
  6713     conditions before applying the rewrite rule):
  6714     ML "simp_depth_limit := n"
  6715     where n is an integer. Thus you can force termination where previously
  6716     the simplifier would diverge.
  6717 
  6718   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6719 
  6720   - No longer aborts on failed congruence proof.  Instead, the
  6721     congruence is ignored.
  6722 
  6723 * Pure: New generic framework for extracting programs from constructive
  6724   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6725   as HOL/Extraction for some case studies.
  6726 
  6727 * Pure: The main goal of the proof state is no longer shown by default, only
  6728 the subgoals. This behaviour is controlled by a new flag.
  6729    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6730 (ML: Proof.show_main_goal).
  6731 
  6732 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6733 rules whose conclusion matches subgoal 1:
  6734       PG menu: Isabelle/Isar -> Show me -> matching rules
  6735 The rules are ordered by how closely they match the subgoal.
  6736 In particular, rules that solve a subgoal outright are displayed first
  6737 (or rather last, the way they are printed).
  6738 (ML: ProofGeneral.print_intros())
  6739 
  6740 * Pure: New flag trace_unify_fail causes unification to print
  6741 diagnostic information (PG: in trace buffer) when it fails. This is
  6742 useful for figuring out why single step proofs like rule, erule or
  6743 assumption failed.
  6744 
  6745 * Pure: Locale specifications now produce predicate definitions
  6746 according to the body of text (covering assumptions modulo local
  6747 definitions); predicate "loc_axioms" covers newly introduced text,
  6748 while "loc" is cumulative wrt. all included locale expressions; the
  6749 latter view is presented only on export into the global theory
  6750 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6751 on the old view without predicates;
  6752 
  6753 * Pure: predefined locales "var" and "struct" are useful for sharing
  6754 parameters (as in CASL, for example); just specify something like
  6755 ``var x + var y + struct M'' as import;
  6756 
  6757 * Pure: improved thms_containing: proper indexing of facts instead of
  6758 raw theorems; check validity of results wrt. current name space;
  6759 include local facts of proof configuration (also covers active
  6760 locales), cover fixed variables in index; may use "_" in term
  6761 specification; an optional limit for the number of printed facts may
  6762 be given (the default is 40);
  6763 
  6764 * Pure: disallow duplicate fact bindings within new-style theory files
  6765 (batch-mode only);
  6766 
  6767 * Provers: improved induct method: assumptions introduced by case
  6768 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6769 the goal statement); "foo" still refers to all facts collectively;
  6770 
  6771 * Provers: the function blast.overloaded has been removed: all constants
  6772 are regarded as potentially overloaded, which improves robustness in exchange
  6773 for slight decrease in efficiency;
  6774 
  6775 * Provers/linorder: New generic prover for transitivity reasoning over
  6776 linear orders.  Note: this prover is not efficient!
  6777 
  6778 * Isar: preview of problems to finish 'show' now produce an error
  6779 rather than just a warning (in interactive mode);
  6780 
  6781 
  6782 *** HOL ***
  6783 
  6784 * arith(_tac)
  6785 
  6786  - Produces a counter example if it cannot prove a goal.
  6787    Note that the counter example may be spurious if the goal is not a formula
  6788    of quantifier-free linear arithmetic.
  6789    In ProofGeneral the counter example appears in the trace buffer.
  6790 
  6791  - Knows about div k and mod k where k is a numeral of type nat or int.
  6792 
  6793  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6794    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6795    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6796 
  6797 * simp's arithmetic capabilities have been enhanced a bit: it now
  6798 takes ~= in premises into account (by performing a case split);
  6799 
  6800 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6801 are distributed over a sum of terms;
  6802 
  6803 * New tactic "trans_tac" and method "trans" instantiate
  6804 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6805 "<=", "<" and "=").
  6806 
  6807 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6808 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6809 
  6810 * 'typedef' command has new option "open" to suppress the set
  6811 definition;
  6812 
  6813 * functions Min and Max on finite sets have been introduced (theory
  6814 Finite_Set);
  6815 
  6816 * attribute [symmetric] now works for relations as well; it turns
  6817 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6818 
  6819 * induct over a !!-quantified statement (say !!x1..xn):
  6820   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6821 
  6822 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6823 %x. None. Warning: empty_def now refers to the previously hidden definition
  6824 of the empty set.
  6825 
  6826 * Algebra: formalization of classical algebra.  Intended as base for
  6827 any algebraic development in Isabelle.  Currently covers group theory
  6828 (up to Sylow's theorem) and ring theory (Universal Property of
  6829 Univariate Polynomials).  Contributions welcome;
  6830 
  6831 * GroupTheory: deleted, since its material has been moved to Algebra;
  6832 
  6833 * Complex: new directory of the complex numbers with numeric constants,
  6834 nonstandard complex numbers, and some complex analysis, standard and
  6835 nonstandard (Jacques Fleuriot);
  6836 
  6837 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6838 
  6839 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6840 Fleuriot);
  6841 
  6842 * Real/HahnBanach: updated and adapted to locales;
  6843 
  6844 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6845 Gray and Kramer);
  6846 
  6847 * UNITY: added the Meier-Sanders theory of progress sets;
  6848 
  6849 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6850 as abstract algorithms, instantiated to the JVM;
  6851 
  6852 * Bali: Java source language formalization. Type system, operational
  6853 semantics, axiomatic semantics. Supported language features:
  6854 classes, interfaces, objects,virtual methods, static methods,
  6855 static/instance fields, arrays, access modifiers, definite
  6856 assignment, exceptions.
  6857 
  6858 
  6859 *** ZF ***
  6860 
  6861 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6862 universe, etc.);
  6863 
  6864 * Main ZF: virtually all theories converted to new-style format;
  6865 
  6866 
  6867 *** ML ***
  6868 
  6869 * Pure: Tactic.prove provides sane interface for internal proofs;
  6870 omits the infamous "standard" operation, so this is more appropriate
  6871 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6872 
  6873 * Pure: improved error reporting of simprocs;
  6874 
  6875 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6876 up simprocs;
  6877 
  6878 
  6879 *** Document preparation ***
  6880 
  6881 * uses \par instead of \\ for line breaks in theory text. This may
  6882 shift some page breaks in large documents. To get the old behaviour
  6883 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6884 
  6885 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6886 other packages
  6887 
  6888 * \<euro> now needs package babel/greek instead of marvosym (which
  6889 broke \Rightarrow)
  6890 
  6891 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6892 textcomp package)
  6893 
  6894 
  6895 
  6896 New in Isabelle2002 (March 2002)
  6897 --------------------------------
  6898 
  6899 *** Document preparation ***
  6900 
  6901 * greatly simplified document preparation setup, including more
  6902 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6903 instructive isatool mkdir; users should basically be able to get
  6904 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6905 users may run a separate document processing stage manually like this:
  6906 "isatool usedir -D output HOL Test && isatool document Test/output";
  6907 
  6908 * theory dependency graph may now be incorporated into documents;
  6909 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6910 with \includegraphics of LaTeX;
  6911 
  6912 * proper spacing of consecutive markup elements, especially text
  6913 blocks after section headings;
  6914 
  6915 * support bold style (for single symbols only), input syntax is like
  6916 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6917 
  6918 * \<bullet> is now output as bold \cdot by default, which looks much
  6919 better in printed text;
  6920 
  6921 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6922 note that these symbols are currently unavailable in Proof General /
  6923 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6924 
  6925 * isatool latex no longer depends on changed TEXINPUTS, instead
  6926 isatool document copies the Isabelle style files to the target
  6927 location;
  6928 
  6929 
  6930 *** Isar ***
  6931 
  6932 * Pure/Provers: improved proof by cases and induction;
  6933   - 'case' command admits impromptu naming of parameters (such as
  6934     "case (Suc n)");
  6935   - 'induct' method divinates rule instantiation from the inductive
  6936     claim; no longer requires excessive ?P bindings for proper
  6937     instantiation of cases;
  6938   - 'induct' method properly enumerates all possibilities of set/type
  6939     rules; as a consequence facts may be also passed through *type*
  6940     rules without further ado;
  6941   - 'induct' method now derives symbolic cases from the *rulified*
  6942     rule (before it used to rulify cases stemming from the internal
  6943     atomized version); this means that the context of a non-atomic
  6944     statement becomes is included in the hypothesis, avoiding the
  6945     slightly cumbersome show "PROP ?case" form;
  6946   - 'induct' may now use elim-style induction rules without chaining
  6947     facts, using ``missing'' premises from the goal state; this allows
  6948     rules stemming from inductive sets to be applied in unstructured
  6949     scripts, while still benefitting from proper handling of non-atomic
  6950     statements; NB: major inductive premises need to be put first, all
  6951     the rest of the goal is passed through the induction;
  6952   - 'induct' proper support for mutual induction involving non-atomic
  6953     rule statements (uses the new concept of simultaneous goals, see
  6954     below);
  6955   - append all possible rule selections, but only use the first
  6956     success (no backtracking);
  6957   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6958   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6959   - added 'print_induct_rules' (covered by help item in recent Proof
  6960     General versions);
  6961   - moved induct/cases attributes to Pure, methods to Provers;
  6962   - generic method setup instantiated for FOL and HOL;
  6963 
  6964 * Pure: support multiple simultaneous goal statements, for example
  6965 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6966 meta-level mechanism, this acts as if several individual goals had
  6967 been stated separately; in particular common proof methods need to be
  6968 repeated in order to cover all claims; note that a single elimination
  6969 step is *not* sufficient to establish the two conjunctions, so this
  6970 fails:
  6971 
  6972   assume "A & B" then have A and B ..   (*".." fails*)
  6973 
  6974 better use "obtain" in situations as above; alternative refer to
  6975 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6976 
  6977 * Pure: proper integration with ``locales''; unlike the original
  6978 version by Florian Kammller, Isar locales package high-level proof
  6979 contexts rather than raw logical ones (e.g. we admit to include
  6980 attributes everywhere); operations on locales include merge and
  6981 rename; support for implicit arguments (``structures''); simultaneous
  6982 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6983 some examples;
  6984 
  6985 * Pure: the following commands have been ``localized'', supporting a
  6986 target locale specification "(in name)": 'lemma', 'theorem',
  6987 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6988 stored both within the locale and at the theory level (exported and
  6989 qualified by the locale name);
  6990 
  6991 * Pure: theory goals may now be specified in ``long'' form, with
  6992 ad-hoc contexts consisting of arbitrary locale elements. for example
  6993 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6994 definitions may be given, too); the result is a meta-level rule with
  6995 the context elements being discharged in the obvious way;
  6996 
  6997 * Pure: new proof command 'using' allows to augment currently used
  6998 facts after a goal statement ('using' is syntactically analogous to
  6999 'apply', but acts on the goal's facts only); this allows chained facts
  7000 to be separated into parts given before and after a claim, as in
  7001 ``from a and b have C using d and e <proof>'';
  7002 
  7003 * Pure: renamed "antecedent" case to "rule_context";
  7004 
  7005 * Pure: new 'judgment' command records explicit information about the
  7006 object-logic embedding (used by several tools internally); no longer
  7007 use hard-wired "Trueprop";
  7008 
  7009 * Pure: added 'corollary' command;
  7010 
  7011 * Pure: fixed 'token_translation' command;
  7012 
  7013 * Pure: removed obsolete 'exported' attribute;
  7014 
  7015 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  7016 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  7017 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  7018 
  7019 * Pure: method 'atomize' presents local goal premises as object-level
  7020 statements (atomic meta-level propositions); setup controlled via
  7021 rewrite rules declarations of 'atomize' attribute; example
  7022 application: 'induct' method with proper rule statements in improper
  7023 proof *scripts*;
  7024 
  7025 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  7026 now consider the syntactic context of assumptions, giving a better
  7027 chance to get type-inference of the arguments right (this is
  7028 especially important for locales);
  7029 
  7030 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  7031 mode;
  7032 
  7033 * Pure/obtain: the formal conclusion "thesis", being marked as
  7034 ``internal'', may no longer be reference directly in the text;
  7035 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  7036 situations;
  7037 
  7038 * Pure: generic 'sym' attribute which declares a rule both as pure
  7039 'elim?' and for the 'symmetric' operation;
  7040 
  7041 * Pure: marginal comments ``--'' may now occur just anywhere in the
  7042 text; the fixed correlation with particular command syntax has been
  7043 discontinued;
  7044 
  7045 * Pure: new method 'rules' is particularly well-suited for proof
  7046 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  7047 but often produces more compact proof terms with less detours;
  7048 
  7049 * Pure/Provers/classical: simplified integration with pure rule
  7050 attributes and methods; the classical "intro?/elim?/dest?"
  7051 declarations coincide with the pure ones; the "rule" method no longer
  7052 includes classically swapped intros; "intro" and "elim" methods no
  7053 longer pick rules from the context; also got rid of ML declarations
  7054 AddXIs/AddXEs/AddXDs; all of this has some potential for
  7055 INCOMPATIBILITY;
  7056 
  7057 * Provers/classical: attribute 'swapped' produces classical inversions
  7058 of introduction rules;
  7059 
  7060 * Provers/simplifier: 'simplified' attribute may refer to explicit
  7061 rules instead of full simplifier context; 'iff' attribute handles
  7062 conditional rules;
  7063 
  7064 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  7065 
  7066 * HOL: 'recdef' now fails on unfinished automated proofs, use
  7067 "(permissive)" option to recover old behavior;
  7068 
  7069 * HOL: 'inductive' no longer features separate (collective) attributes
  7070 for 'intros' (was found too confusing);
  7071 
  7072 * HOL: properly declared induction rules less_induct and
  7073 wf_induct_rule;
  7074 
  7075 
  7076 *** HOL ***
  7077 
  7078 * HOL: moved over to sane numeral syntax; the new policy is as
  7079 follows:
  7080 
  7081   - 0 and 1 are polymorphic constants, which are defined on any
  7082   numeric type (nat, int, real etc.);
  7083 
  7084   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  7085   binary representation internally;
  7086 
  7087   - type nat has special constructor Suc, and generally prefers Suc 0
  7088   over 1::nat and Suc (Suc 0) over 2::nat;
  7089 
  7090 This change may cause significant problems of INCOMPATIBILITY; here
  7091 are some hints on converting existing sources:
  7092 
  7093   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  7094   entities, so expressions involving "-" (unary or binary minus) need
  7095   to be spaced properly;
  7096 
  7097   - existing occurrences of "1" may need to be constraint "1::nat" or
  7098   even replaced by Suc 0; similar for old "2";
  7099 
  7100   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  7101 
  7102   - remove all special provisions on numerals in proofs;
  7103 
  7104 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  7105 representation (depends on bin_arith_simps in the default context);
  7106 
  7107 * HOL: symbolic syntax for x^2 (numeral 2);
  7108 
  7109 * HOL: the class of all HOL types is now called "type" rather than
  7110 "term"; INCOMPATIBILITY, need to adapt references to this type class
  7111 in axclass/classes, instance/arities, and (usually rare) occurrences
  7112 in typings (of consts etc.); internally the class is called
  7113 "HOL.type", ML programs should refer to HOLogic.typeS;
  7114 
  7115 * HOL/record package improvements:
  7116   - new derived operations "fields" to build a partial record section,
  7117     "extend" to promote a fixed record to a record scheme, and
  7118     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  7119     declared as simp by default;
  7120   - shared operations ("more", "fields", etc.) now need to be always
  7121     qualified) --- potential INCOMPATIBILITY;
  7122   - removed "make_scheme" operations (use "make" with "extend") --
  7123     INCOMPATIBILITY;
  7124   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  7125   - provides cases/induct rules for use with corresponding Isar
  7126     methods (for concrete records, record schemes, concrete more
  7127     parts, and schematic more parts -- in that order);
  7128   - internal definitions directly based on a light-weight abstract
  7129     theory of product types over typedef rather than datatype;
  7130 
  7131 * HOL: generic code generator for generating executable ML code from
  7132 specifications; specific support for HOL constructs such as inductive
  7133 datatypes and sets, as well as recursive functions; can be invoked
  7134 via 'generate_code' theory section;
  7135 
  7136 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  7137 
  7138 * HOL: consolidated and renamed several theories.  In particular:
  7139         Ord.thy has been absorbed into HOL.thy
  7140         String.thy has been absorbed into List.thy
  7141 
  7142 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  7143 (beware of argument permutation!);
  7144 
  7145 * HOL: linorder_less_split superseded by linorder_cases;
  7146 
  7147 * HOL/List: "nodups" renamed to "distinct";
  7148 
  7149 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  7150 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  7151   - Ex_def has changed, now need to use some_eq_ex
  7152 
  7153 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  7154 in this (rare) case use:
  7155 
  7156   delSWrapper "split_all_tac"
  7157   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  7158 
  7159 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  7160 MAY FAIL;
  7161 
  7162 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  7163 Isabelle's type classes, ^ on functions and relations has too general
  7164 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  7165 necessary to attach explicit type constraints;
  7166 
  7167 * HOL/Relation: the prefix name of the infix "O" has been changed from
  7168 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  7169 renamed accordingly (eg "compI" -> "rel_compI").
  7170 
  7171 * HOL: syntax translations now work properly with numerals and records
  7172 expressions;
  7173 
  7174 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  7175 of "lam" -- INCOMPATIBILITY;
  7176 
  7177 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  7178 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  7179 renamed "Product_Type.unit";
  7180 
  7181 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  7182 
  7183 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  7184 the "cases" method);
  7185 
  7186 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  7187 Florian Kammller);
  7188 
  7189 * HOL/IMP: updated and converted to new-style theory format; several
  7190 parts turned into readable document, with proper Isar proof texts and
  7191 some explanations (by Gerwin Klein);
  7192 
  7193 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  7194 
  7195 * HOL-Hyperreal is now a logic image;
  7196 
  7197 
  7198 *** HOLCF ***
  7199 
  7200 * Isar: consts/constdefs supports mixfix syntax for continuous
  7201 operations;
  7202 
  7203 * Isar: domain package adapted to new-style theory format, e.g. see
  7204 HOLCF/ex/Dnat.thy;
  7205 
  7206 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7207 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7208 lift.induct_tac, always use UU instead of Undef;
  7209 
  7210 * HOLCF/IMP: updated and converted to new-style theory;
  7211 
  7212 
  7213 *** ZF ***
  7214 
  7215 * Isar: proper integration of logic-specific tools and packages,
  7216 including theory commands '(co)inductive', '(co)datatype',
  7217 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7218 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7219 
  7220 * theory Main no longer includes AC; for the Axiom of Choice, base
  7221 your theory on Main_ZFC;
  7222 
  7223 * the integer library now covers quotients and remainders, with many
  7224 laws relating division to addition, multiplication, etc.;
  7225 
  7226 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7227 typeless version of the formalism;
  7228 
  7229 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7230 format;
  7231 
  7232 * ZF/Induct: new directory for examples of inductive definitions,
  7233 including theory Multiset for multiset orderings; converted to
  7234 new-style theory format;
  7235 
  7236 * ZF: many new theorems about lists, ordinals, etc.;
  7237 
  7238 
  7239 *** General ***
  7240 
  7241 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7242 variable proof controls level of detail: 0 = no proofs (only oracle
  7243 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7244 also ref manual for further ML interfaces;
  7245 
  7246 * Pure/axclass: removed obsolete ML interface
  7247 goal_subclass/goal_arity;
  7248 
  7249 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7250 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7251 separate tokens, so expressions involving minus need to be spaced
  7252 properly;
  7253 
  7254 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7255 rather than "infixl" or "infixr";
  7256 
  7257 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7258 sort constraint specifications in type inference; e.g. "x::_::foo"
  7259 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7260 type variable);
  7261 
  7262 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7263 control output of nested => (types); the default behavior is
  7264 "type_brackets";
  7265 
  7266 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7267 tokens into AST constants;
  7268 
  7269 * Pure/syntax: prefer later declarations of translations and print
  7270 translation functions; potential INCOMPATIBILITY: need to reverse
  7271 multiple declarations for same syntax element constant;
  7272 
  7273 * Pure/show_hyps reset by default (in accordance to existing Isar
  7274 practice);
  7275 
  7276 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7277 addSafter;
  7278 
  7279 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7280 as well;
  7281 
  7282 * system: tested support for MacOS X; should be able to get Isabelle +
  7283 Proof General to work in a plain Terminal after installing Poly/ML
  7284 (e.g. from the Isabelle distribution area) and GNU bash alone
  7285 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7286 support requires further installations, e.g. from
  7287 http://fink.sourceforge.net/);
  7288 
  7289 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7290 
  7291 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7292 of 40 MB), cf. ML_OPTIONS;
  7293 
  7294 * system: Proof General keywords specification is now part of the
  7295 Isabelle distribution (see etc/isar-keywords.el);
  7296 
  7297 * system: support for persistent Proof General sessions (refrain from
  7298 outdating all loaded theories on startup); user may create writable
  7299 logic images like this: ``isabelle -q HOL Test'';
  7300 
  7301 * system: smart selection of Isabelle process versus Isabelle
  7302 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7303 run both "isabelle" and "Isabelle" even if file names are badly
  7304 damaged (executable inspects the case of the first letter of its own
  7305 name); added separate "isabelle-process" and "isabelle-interface";
  7306 
  7307 * system: refrain from any attempt at filtering input streams; no
  7308 longer support ``8bit'' encoding of old isabelle font, instead proper
  7309 iso-latin characters may now be used; the related isatools
  7310 "symbolinput" and "nonascii" have disappeared as well;
  7311 
  7312 * system: removed old "xterm" interface (the print modes "xterm" and
  7313 "xterm_color" are still available for direct use in a suitable
  7314 terminal);
  7315 
  7316 
  7317 
  7318 New in Isabelle99-2 (February 2001)
  7319 -----------------------------------
  7320 
  7321 *** Overview of INCOMPATIBILITIES ***
  7322 
  7323 * HOL: please note that theories in the Library and elsewhere often use the
  7324 new-style (Isar) format; to refer to their theorems in an ML script you must
  7325 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  7326 
  7327 * HOL: inductive package no longer splits induction rule aggressively,
  7328 but only as far as specified by the introductions given; the old
  7329 format may be recovered via ML function complete_split_rule or attribute
  7330 'split_rule (complete)';
  7331 
  7332 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  7333 gfp_Tarski to gfp_unfold;
  7334 
  7335 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  7336 
  7337 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  7338 relation); infix "^^" has been renamed "``"; infix "``" has been
  7339 renamed "`"; "univalent" has been renamed "single_valued";
  7340 
  7341 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  7342 operation;
  7343 
  7344 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  7345 
  7346 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  7347 
  7348 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  7349 consequence, it is no longer monotonic wrt. the local goal context
  7350 (which is now passed through the inductive cases);
  7351 
  7352 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  7353 \<gg> to \<ggreater>;
  7354 
  7355 
  7356 *** Document preparation ***
  7357 
  7358 * \isabellestyle{NAME} selects version of Isabelle output (currently
  7359 available: are "it" for near math-mode best-style output, "sl" for
  7360 slanted text style, and "tt" for plain type-writer; if no
  7361 \isabellestyle command is given, output is according to slanted
  7362 type-writer);
  7363 
  7364 * support sub/super scripts (for single symbols only), input syntax is
  7365 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  7366 
  7367 * some more standard symbols; see Appendix A of the system manual for
  7368 the complete list of symbols defined in isabellesym.sty;
  7369 
  7370 * improved isabelle style files; more abstract symbol implementation
  7371 (should now use \isamath{...} and \isatext{...} in custom symbol
  7372 definitions);
  7373 
  7374 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  7375 state; Note that presentation of goal states does not conform to
  7376 actual human-readable proof documents.  Please do not include goal
  7377 states into document output unless you really know what you are doing!
  7378 
  7379 * proper indentation of antiquoted output with proportional LaTeX
  7380 fonts;
  7381 
  7382 * no_document ML operator temporarily disables LaTeX document
  7383 generation;
  7384 
  7385 * isatool unsymbolize tunes sources for plain ASCII communication;
  7386 
  7387 
  7388 *** Isar ***
  7389 
  7390 * Pure: Isar now suffers initial goal statements to contain unbound
  7391 schematic variables (this does not conform to actual readable proof
  7392 documents, due to unpredictable outcome and non-compositional proof
  7393 checking); users who know what they are doing may use schematic goals
  7394 for Prolog-style synthesis of proven results;
  7395 
  7396 * Pure: assumption method (an implicit finishing) now handles actual
  7397 rules as well;
  7398 
  7399 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  7400 initial goal, declare "that" only as Pure intro (only for single
  7401 steps); the "that" rule assumption may now be involved in implicit
  7402 finishing, thus ".." becomes a feasible for trivial obtains;
  7403 
  7404 * Pure: default proof step now includes 'intro_classes'; thus trivial
  7405 instance proofs may be performed by "..";
  7406 
  7407 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  7408 statements as well;
  7409 
  7410 * Pure: more robust selection of calculational rules;
  7411 
  7412 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  7413 rule (as well as the assumption rule);
  7414 
  7415 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  7416 lemmas, using the graph browser tool;
  7417 
  7418 * Pure: predict failure of "show" in interactive mode;
  7419 
  7420 * Pure: 'thms_containing' now takes actual terms as arguments;
  7421 
  7422 * HOL: improved method 'induct' --- now handles non-atomic goals
  7423 (potential INCOMPATIBILITY); tuned error handling;
  7424 
  7425 * HOL: cases and induct rules now provide explicit hints about the
  7426 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  7427 any remaining facts are inserted into the goal verbatim;
  7428 
  7429 * HOL: local contexts (aka cases) may now contain term bindings as
  7430 well; the 'cases' and 'induct' methods new provide a ?case binding for
  7431 the result to be shown in each case;
  7432 
  7433 * HOL: added 'recdef_tc' command;
  7434 
  7435 * isatool convert assists in eliminating legacy ML scripts;
  7436 
  7437 
  7438 *** HOL ***
  7439 
  7440 * HOL/Library: a collection of generic theories to be used together
  7441 with main HOL; the theory loader path already includes this directory
  7442 by default; the following existing theories have been moved here:
  7443 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  7444 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  7445 
  7446 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  7447 modelling and verification task performed in Isabelle/HOL +
  7448 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  7449 
  7450 * HOL/Algebra: special summation operator SUM no longer exists, it has
  7451 been replaced by setsum; infix 'assoc' now has priority 50 (like
  7452 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  7453 'domain', this makes the theory consistent with mathematical
  7454 literature;
  7455 
  7456 * HOL basics: added overloaded operations "inverse" and "divide"
  7457 (infix "/"), syntax for generic "abs" operation, generic summation
  7458 operator \<Sum>;
  7459 
  7460 * HOL/typedef: simplified package, provide more useful rules (see also
  7461 HOL/subset.thy);
  7462 
  7463 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  7464 now expressed as a proper nested rule (old-style tactic scripts may
  7465 require atomize_strip_tac to cope with non-atomic premises);
  7466 
  7467 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  7468 to "split_conv" (old name still available for compatibility);
  7469 
  7470 * HOL: improved concrete syntax for strings (e.g. allows translation
  7471 rules with string literals);
  7472 
  7473 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  7474  and Fleuriot's mechanization of analysis, including the transcendental
  7475  functions for the reals;
  7476 
  7477 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  7478 
  7479 
  7480 *** CTT ***
  7481 
  7482 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  7483 "lam" is displayed as TWO lambda-symbols
  7484 
  7485 * CTT: theory Main now available, containing everything (that is, Bool
  7486 and Arith);
  7487 
  7488 
  7489 *** General ***
  7490 
  7491 * Pure: the Simplifier has been implemented properly as a derived rule
  7492 outside of the actual kernel (at last!); the overall performance
  7493 penalty in practical applications is about 50%, while reliability of
  7494 the Isabelle inference kernel has been greatly improved;
  7495 
  7496 * print modes "brackets" and "no_brackets" control output of nested =>
  7497 (types) and ==> (props); the default behaviour is "brackets";
  7498 
  7499 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7500 as assumptions as well;
  7501 
  7502 * system: support Poly/ML 4.0;
  7503 
  7504 * system: isatool install handles KDE version 1 or 2;
  7505 
  7506 
  7507 
  7508 New in Isabelle99-1 (October 2000)
  7509 ----------------------------------
  7510 
  7511 *** Overview of INCOMPATIBILITIES ***
  7512 
  7513 * HOL: simplification of natural numbers is much changed; to partly
  7514 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7515 issue the following ML commands:
  7516 
  7517   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7518   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7519 
  7520 * HOL: simplification no longer dives into case-expressions; this is
  7521 controlled by "t.weak_case_cong" for each datatype t;
  7522 
  7523 * HOL: nat_less_induct renamed to less_induct;
  7524 
  7525 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7526 fixsome to patch .thy and .ML sources automatically;
  7527 
  7528   select_equality  -> some_equality
  7529   select_eq_Ex     -> some_eq_ex
  7530   selectI2EX       -> someI2_ex
  7531   selectI2         -> someI2
  7532   selectI          -> someI
  7533   select1_equality -> some1_equality
  7534   Eps_sym_eq       -> some_sym_eq_trivial
  7535   Eps_eq           -> some_eq_trivial
  7536 
  7537 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7538 
  7539 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7540 instead);
  7541 
  7542 * HOL: the recursion equations generated by 'recdef' are now called
  7543 f.simps instead of f.rules;
  7544 
  7545 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7546 
  7547 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7548 sometimes be needed;
  7549 
  7550 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7551 
  7552 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7553 
  7554 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7555 product is now "<*>" instead of "Times"; the lexicographic product is
  7556 now "<*lex*>" instead of "**";
  7557 
  7558 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7559 of main HOL, but was unused); better use HOL's datatype package;
  7560 
  7561 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7562 the old syntax may be recovered as follows:
  7563 
  7564   syntax (symbols)
  7565     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7566       (infixl "\\<oplus>" 100)
  7567 
  7568 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7569 
  7570 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7571 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7572 internally;
  7573 
  7574 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7575 changed from A/r to A//r;
  7576 
  7577 * ZF: new treatment of arithmetic (nat & int) may break some old
  7578 proofs;
  7579 
  7580 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7581 rulify -> rule_format, elimify -> elim_format, ...);
  7582 
  7583 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7584 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7585 should have to change intro!! to intro? only); replaced "delrule" by
  7586 "rule del";
  7587 
  7588 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7589 
  7590 * Provers: strengthened force_tac by using new first_best_tac;
  7591 
  7592 * LaTeX document preparation: several changes of isabelle.sty (see
  7593 lib/texinputs);
  7594 
  7595 
  7596 *** Document preparation ***
  7597 
  7598 * formal comments (text blocks etc.) in new-style theories may now
  7599 contain antiquotations of thm/prop/term/typ/text to be presented
  7600 according to latex print mode; concrete syntax is like this:
  7601 @{term[show_types] "f(x) = a + x"};
  7602 
  7603 * isatool mkdir provides easy setup of Isabelle session directories,
  7604 including proper document sources;
  7605 
  7606 * generated LaTeX sources are now deleted after successful run
  7607 (isatool document -c); may retain a copy somewhere else via -D option
  7608 of isatool usedir;
  7609 
  7610 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7611 style files, achieving self-contained LaTeX sources and simplifying
  7612 LaTeX debugging;
  7613 
  7614 * old-style theories now produce (crude) LaTeX output as well;
  7615 
  7616 * browser info session directories are now self-contained (may be put
  7617 on WWW server seperately); improved graphs of nested sessions; removed
  7618 graph for 'all sessions';
  7619 
  7620 * several improvements in isabelle style files; \isabellestyle{it}
  7621 produces fake math mode output; \isamarkupheader is now \section by
  7622 default; see lib/texinputs/isabelle.sty etc.;
  7623 
  7624 
  7625 *** Isar ***
  7626 
  7627 * Isar/Pure: local results and corresponding term bindings are now
  7628 subject to Hindley-Milner polymorphism (similar to ML); this
  7629 accommodates incremental type-inference very nicely;
  7630 
  7631 * Isar/Pure: new derived language element 'obtain' supports
  7632 generalized existence reasoning;
  7633 
  7634 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7635 support accumulation of results, without applying any rules yet;
  7636 useful to collect intermediate results without explicit name
  7637 references, and for use with transitivity rules with more than 2
  7638 premises;
  7639 
  7640 * Isar/Pure: scalable support for case-analysis type proofs: new
  7641 'case' language element refers to local contexts symbolically, as
  7642 produced by certain proof methods; internally, case names are attached
  7643 to theorems as "tags";
  7644 
  7645 * Isar/Pure: theory command 'hide' removes declarations from
  7646 class/type/const name spaces;
  7647 
  7648 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7649 indicate potential overloading;
  7650 
  7651 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7652 
  7653 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7654 "{a,b,c}" instead of {a,b,c};
  7655 
  7656 * Isar/Pure now provides its own version of intro/elim/dest
  7657 attributes; useful for building new logics, but beware of confusion
  7658 with the version in Provers/classical;
  7659 
  7660 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7661 case name 'antecedent';
  7662 
  7663 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7664 to the current context is now done automatically);
  7665 
  7666 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7667 for definining proof methods in ML;
  7668 
  7669 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7670 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7671 most cases, one should have to change intro!! to intro? only);
  7672 replaced "delrule" by "rule del";
  7673 
  7674 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7675 'symmetric' attribute (the latter supercedes [RS sym]);
  7676 
  7677 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7678 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7679 well (including splits);
  7680 
  7681 * Isar/Provers: Simplifier and Classical methods now support all kind
  7682 of modifiers used in the past, including 'cong', 'iff', etc.
  7683 
  7684 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7685 of Simplifier and Classical reasoner);
  7686 
  7687 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7688 now support named cases; major packages (inductive, datatype, primrec,
  7689 recdef) support case names and properly name parameters;
  7690 
  7691 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7692 monotonicity conditions are extracted to be proven at end of
  7693 calculations;
  7694 
  7695 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7696 method anyway;
  7697 
  7698 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7699 split_if split_if_asm; datatype package provides theorems foo.splits =
  7700 foo.split foo.split_asm for each datatype;
  7701 
  7702 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7703 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7704 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  7705 use "(cases (simplified))" method in proper proof texts);
  7706 
  7707 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  7708 
  7709 * Isar: names of theorems etc. may be natural numbers as well;
  7710 
  7711 * Isar: 'pr' command: optional arguments for goals_limit and
  7712 ProofContext.prems_limit; no longer prints theory contexts, but only
  7713 proof states;
  7714 
  7715 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  7716 additional print modes to be specified; e.g. "pr(latex)" will print
  7717 proof state according to the Isabelle LaTeX style;
  7718 
  7719 * Isar: improved support for emulating tactic scripts, including proof
  7720 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  7721 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  7722 (for HOL datatypes);
  7723 
  7724 * Isar: simplified (more robust) goal selection of proof methods: 1st
  7725 goal, all goals, or explicit goal specifier (tactic emulation); thus
  7726 'proof method scripts' have to be in depth-first order;
  7727 
  7728 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  7729 
  7730 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  7731 should instead use individual commands for printing items
  7732 (print_commands, print_methods etc.);
  7733 
  7734 * Isar: added 'nothing' --- the empty list of theorems;
  7735 
  7736 
  7737 *** HOL ***
  7738 
  7739 * HOL/MicroJava: formalization of a fragment of Java, together with a
  7740 corresponding virtual machine and a specification of its bytecode
  7741 verifier and a lightweight bytecode verifier, including proofs of
  7742 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  7743 Cornelia Pusch (see also the homepage of project Bali at
  7744 http://isabelle.in.tum.de/Bali/);
  7745 
  7746 * HOL/Algebra: new theory of rings and univariate polynomials, by
  7747 Clemens Ballarin;
  7748 
  7749 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  7750 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  7751 Rasmussen;
  7752 
  7753 * HOL/Lattice: fundamental concepts of lattice theory and order
  7754 structures, including duals, properties of bounds versus algebraic
  7755 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  7756 Theorem for complete lattices etc.; may also serve as a demonstration
  7757 for abstract algebraic reasoning using axiomatic type classes, and
  7758 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  7759 
  7760 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  7761 von Oheimb;
  7762 
  7763 * HOL/IMPP: extension of IMP with local variables and mutually
  7764 recursive procedures, by David von Oheimb;
  7765 
  7766 * HOL/Lambda: converted into new-style theory and document;
  7767 
  7768 * HOL/ex/Multiquote: example of multiple nested quotations and
  7769 anti-quotations -- basically a generalized version of de-Bruijn
  7770 representation; very useful in avoiding lifting of operations;
  7771 
  7772 * HOL/record: added general record equality rule to simpset; fixed
  7773 select-update simplification procedure to handle extended records as
  7774 well; admit "r" as field name;
  7775 
  7776 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  7777 other numeric types and also as the identity of groups, rings, etc.;
  7778 
  7779 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  7780 Types nat and int belong to this axclass;
  7781 
  7782 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  7783    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  7784    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  7785   two terms #m*u and #n*u are replaced by #(m+n)*u
  7786     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  7787   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  7788     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  7789 
  7790 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  7791 powerful prover for predicate logic but knows nothing of clasets; see
  7792 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  7793 
  7794 * HOL: new version of "case_tac" subsumes both boolean case split and
  7795 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  7796 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  7797 
  7798 * HOL: simplification no longer dives into case-expressions: only the
  7799 selector expression is simplified, but not the remaining arms; to
  7800 enable full simplification of case-expressions for datatype t, you may
  7801 remove t.weak_case_cong from the simpset, either globally (Delcongs
  7802 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  7803 
  7804 * HOL/recdef: the recursion equations generated by 'recdef' for
  7805 function 'f' are now called f.simps instead of f.rules; if all
  7806 termination conditions are proved automatically, these simplification
  7807 rules are added to the simpset, as in primrec; rules may be named
  7808 individually as well, resulting in a separate list of theorems for
  7809 each equation;
  7810 
  7811 * HOL/While is a new theory that provides a while-combinator. It
  7812 permits the definition of tail-recursive functions without the
  7813 provision of a termination measure. The latter is necessary once the
  7814 invariant proof rule for while is applied.
  7815 
  7816 * HOL: new (overloaded) notation for the set of elements below/above
  7817 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  7818 
  7819 * HOL: theorems impI, allI, ballI bound as "strip";
  7820 
  7821 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  7822 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  7823 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  7824 
  7825 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7826 
  7827 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  7828 main HOL, but was unused);
  7829 
  7830 * HOL: fewer consts declared as global (e.g. have to refer to
  7831 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  7832 
  7833 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  7834 in case of overlap with user translations (e.g. judgements over
  7835 tuples); (note that the underlying logical represenation is still
  7836 bogus);
  7837 
  7838 
  7839 *** ZF ***
  7840 
  7841 * ZF: simplification automatically cancels common terms in arithmetic
  7842 expressions over nat and int;
  7843 
  7844 * ZF: new treatment of nat to minimize type-checking: all operators
  7845 coerce their operands to a natural number using the function natify,
  7846 making the algebraic laws unconditional;
  7847 
  7848 * ZF: as above, for int: operators coerce their operands to an integer
  7849 using the function intify;
  7850 
  7851 * ZF: the integer library now contains many of the usual laws for the
  7852 orderings, including $<=, and monotonicity laws for $+ and $*;
  7853 
  7854 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  7855 simplification;
  7856 
  7857 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  7858 to the simplifier and classical reasoner simultaneously;
  7859 
  7860 
  7861 *** General ***
  7862 
  7863 * Provers: blast_tac now handles actual object-logic rules as
  7864 assumptions; note that auto_tac uses blast_tac internally as well;
  7865 
  7866 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  7867 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  7868 
  7869 * Provers: delrules now handles destruct rules as well (no longer need
  7870 explicit make_elim);
  7871 
  7872 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  7873   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7874 use instead the strong form,
  7875   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7876 in HOL, FOL and ZF the function cla_make_elim will create such rules
  7877 from destruct-rules;
  7878 
  7879 * Provers: Simplifier.easy_setup provides a fast path to basic
  7880 Simplifier setup for new object-logics;
  7881 
  7882 * Pure: AST translation rules no longer require constant head on LHS;
  7883 
  7884 * Pure: improved name spaces: ambiguous output is qualified; support
  7885 for hiding of names;
  7886 
  7887 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  7888 XSYMBOL_HOME; no longer need to do manual configuration in most
  7889 situations;
  7890 
  7891 * system: compression of ML heaps images may now be controlled via -c
  7892 option of isabelle and isatool usedir (currently only observed by
  7893 Poly/ML);
  7894 
  7895 * system: isatool installfonts may handle X-Symbol fonts as well (very
  7896 useful for remote X11);
  7897 
  7898 * system: provide TAGS file for Isabelle sources;
  7899 
  7900 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  7901 order;
  7902 
  7903 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  7904 timing flag supersedes proof_timing and Toplevel.trace;
  7905 
  7906 * ML: new combinators |>> and |>>> for incremental transformations
  7907 with secondary results (e.g. certain theory extensions):
  7908 
  7909 * ML: PureThy.add_defs gets additional argument to indicate potential
  7910 overloading (usually false);
  7911 
  7912 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  7913 results;
  7914 
  7915 
  7916 
  7917 New in Isabelle99 (October 1999)
  7918 --------------------------------
  7919 
  7920 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7921 
  7922 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  7923 are no longer simplified.  (This allows the simplifier to unfold recursive
  7924 functional programs.)  To restore the old behaviour, declare
  7925 
  7926     Delcongs [if_weak_cong];
  7927 
  7928 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  7929 complement;
  7930 
  7931 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  7932 
  7933 * HOL/datatype: mutual_induct_tac no longer exists --
  7934   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  7935 
  7936 * HOL/typedef: fixed type inference for representing set; type
  7937 arguments now have to occur explicitly on the rhs as type constraints;
  7938 
  7939 * ZF: The con_defs part of an inductive definition may no longer refer
  7940 to constants declared in the same theory;
  7941 
  7942 * HOL, ZF: the function mk_cases, generated by the inductive
  7943 definition package, has lost an argument.  To simplify its result, it
  7944 uses the default simpset instead of a supplied list of theorems.
  7945 
  7946 * HOL/List: the constructors of type list are now Nil and Cons;
  7947 
  7948 * Simplifier: the type of the infix ML functions
  7949         setSSolver addSSolver setSolver addSolver
  7950 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  7951 for packaging solvers. A solver is created via
  7952         mk_solver: string -> (thm list -> int -> tactic) -> solver
  7953 where the string argument is only a comment.
  7954 
  7955 
  7956 *** Proof tools ***
  7957 
  7958 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  7959 decision procedure for linear arithmetic. Currently it is used for
  7960 types `nat', `int', and `real' in HOL (see below); it can, should and
  7961 will be instantiated for other types and logics as well.
  7962 
  7963 * The simplifier now accepts rewrite rules with flexible heads, eg
  7964      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  7965   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  7966   matching.
  7967 
  7968 
  7969 *** General ***
  7970 
  7971 * New Isabelle/Isar subsystem provides an alternative to traditional
  7972 tactical theorem proving; together with the ProofGeneral/isar user
  7973 interface it offers an interactive environment for developing human
  7974 readable proof documents (Isar == Intelligible semi-automated
  7975 reasoning); for further information see isatool doc isar-ref,
  7976 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  7977 
  7978 * improved and simplified presentation of theories: better HTML markup
  7979 (including colors), graph views in several sizes; isatool usedir now
  7980 provides a proper interface for user theories (via -P option); actual
  7981 document preparation based on (PDF)LaTeX is available as well (for
  7982 new-style theories only); see isatool doc system for more information;
  7983 
  7984 * native support for Proof General, both for classic Isabelle and
  7985 Isabelle/Isar;
  7986 
  7987 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  7988 using the graph browser tool;
  7989 
  7990 * Isabelle manuals now also available as PDF;
  7991 
  7992 * theory loader rewritten from scratch (may not be fully
  7993 bug-compatible); old loadpath variable has been replaced by show_path,
  7994 add_path, del_path, reset_path functions; new operations such as
  7995 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  7996 isatool doc ref);
  7997 
  7998 * improved isatool install: option -k creates KDE application icon,
  7999 option -p DIR installs standalone binaries;
  8000 
  8001 * added ML_PLATFORM setting (useful for cross-platform installations);
  8002 more robust handling of platform specific ML images for SML/NJ;
  8003 
  8004 * the settings environment is now statically scoped, i.e. it is never
  8005 created again in sub-processes invoked from isabelle, isatool, or
  8006 Isabelle;
  8007 
  8008 * path element specification '~~' refers to '$ISABELLE_HOME';
  8009 
  8010 * in locales, the "assumes" and "defines" parts may be omitted if
  8011 empty;
  8012 
  8013 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  8014 long arrows);
  8015 
  8016 * new print_mode "HTML";
  8017 
  8018 * new flag show_tags controls display of tags of theorems (which are
  8019 basically just comments that may be attached by some tools);
  8020 
  8021 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  8022 mode and goal output format:
  8023 
  8024 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  8025 244c244
  8026 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  8027 ---
  8028 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  8029 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  8030 181c181
  8031 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  8032 ---
  8033 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  8034 
  8035 * function bind_thms stores lists of theorems (cf. bind_thm);
  8036 
  8037 * new shorthand tactics ftac, eatac, datac, fatac;
  8038 
  8039 * qed (and friends) now accept "" as result name; in that case the
  8040 theorem is not stored, but proper checks and presentation of the
  8041 result still apply;
  8042 
  8043 * theorem database now also indexes constants "Trueprop", "all",
  8044 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  8045 
  8046 
  8047 *** HOL ***
  8048 
  8049 ** HOL arithmetic **
  8050 
  8051 * There are now decision procedures for linear arithmetic over nat and
  8052 int:
  8053 
  8054 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  8055 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  8056 are treated as atomic; subformulae not involving type `nat' or `int'
  8057 are ignored; quantified subformulae are ignored unless they are
  8058 positive universal or negative existential. The tactic has to be
  8059 invoked by hand and can be a little bit slow. In particular, the
  8060 running time is exponential in the number of occurrences of `min' and
  8061 `max', and `-' on `nat'.
  8062 
  8063 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  8064 (negated) (in)equalities among the premises and the conclusion into
  8065 account (i.e. no compound formulae) and does not know about `min' and
  8066 `max', and `-' on `nat'. It is fast and is used automatically by the
  8067 simplifier.
  8068 
  8069 NB: At the moment, these decision procedures do not cope with mixed
  8070 nat/int formulae where the two parts interact, such as `m < n ==>
  8071 int(m) < int(n)'.
  8072 
  8073 * HOL/Numeral provides a generic theory of numerals (encoded
  8074 efficiently as bit strings); setup for types nat/int/real is in place;
  8075 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  8076 int, existing theories and proof scripts may require a few additional
  8077 type constraints;
  8078 
  8079 * integer division and remainder can now be performed on constant
  8080 arguments;
  8081 
  8082 * many properties of integer multiplication, division and remainder
  8083 are now available;
  8084 
  8085 * An interface to the Stanford Validity Checker (SVC) is available through the
  8086 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  8087 are proved automatically.  SVC must be installed separately, and its results
  8088 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  8089 invocation of the underlying oracle).  For SVC see
  8090   http://verify.stanford.edu/SVC
  8091 
  8092 * IsaMakefile: the HOL-Real target now builds an actual image;
  8093 
  8094 
  8095 ** HOL misc **
  8096 
  8097 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  8098 (in Isabelle/Isar) -- by Gertrud Bauer;
  8099 
  8100 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  8101 analysis for assembly languages with subtypes;
  8102 
  8103 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  8104 -- avoids syntactic ambiguities and treats state, transition, and
  8105 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  8106 changed syntax and (many) tactics;
  8107 
  8108 * HOL/inductive: Now also handles more general introduction rules such
  8109   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  8110   theorems are now maintained within the theory (maintained via the
  8111   "mono" attribute);
  8112 
  8113 * HOL/datatype: Now also handles arbitrarily branching datatypes
  8114   (using function types) such as
  8115 
  8116   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  8117 
  8118 * HOL/record: record_simproc (part of the default simpset) takes care
  8119 of selectors applied to updated records; record_split_tac is no longer
  8120 part of the default claset; update_defs may now be removed from the
  8121 simpset in many cases; COMPATIBILITY: old behavior achieved by
  8122 
  8123   claset_ref () := claset() addSWrapper record_split_wrapper;
  8124   Delsimprocs [record_simproc]
  8125 
  8126 * HOL/typedef: fixed type inference for representing set; type
  8127 arguments now have to occur explicitly on the rhs as type constraints;
  8128 
  8129 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  8130 names rather than an ML expression;
  8131 
  8132 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  8133 supplied later.  Program schemes can be defined, such as
  8134     "While B C s = (if B s then While B C (C s) else s)"
  8135 where the well-founded relation can be chosen after B and C have been given.
  8136 
  8137 * HOL/List: the constructors of type list are now Nil and Cons;
  8138 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  8139 course, ML tools referring to List.list.op # etc. have to be adapted;
  8140 
  8141 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  8142 disabled by default; run isabelle with option -m HOL to get back to
  8143 the original Gordon/HOL-style output;
  8144 
  8145 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  8146 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  8147 
  8148 * HOL basic syntax simplified (more orthogonal): all variants of
  8149 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  8150 Eps operator is provided as well: "SOME x. P[x]";
  8151 
  8152 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  8153 
  8154 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  8155 thus available for user theories;
  8156 
  8157 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  8158 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  8159 time;
  8160 
  8161 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  8162 several times and then mp;
  8163 
  8164 
  8165 *** LK ***
  8166 
  8167 * the notation <<...>> is now available as a notation for sequences of
  8168 formulas;
  8169 
  8170 * the simplifier is now installed
  8171 
  8172 * the axiom system has been generalized (thanks to Soren Heilmann)
  8173 
  8174 * the classical reasoner now has a default rule database
  8175 
  8176 
  8177 *** ZF ***
  8178 
  8179 * new primrec section allows primitive recursive functions to be given
  8180 directly (as in HOL) over datatypes and the natural numbers;
  8181 
  8182 * new tactics induct_tac and exhaust_tac for induction (or case
  8183 analysis) over datatypes and the natural numbers;
  8184 
  8185 * the datatype declaration of type T now defines the recursor T_rec;
  8186 
  8187 * simplification automatically does freeness reasoning for datatype
  8188 constructors;
  8189 
  8190 * automatic type-inference, with AddTCs command to insert new
  8191 type-checking rules;
  8192 
  8193 * datatype introduction rules are now added as Safe Introduction rules
  8194 to the claset;
  8195 
  8196 * the syntax "if P then x else y" is now available in addition to
  8197 if(P,x,y);
  8198 
  8199 
  8200 *** Internal programming interfaces ***
  8201 
  8202 * tuned simplifier trace output; new flag debug_simp;
  8203 
  8204 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8205 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8206 
  8207 * AxClass.axclass_tac lost the theory argument;
  8208 
  8209 * tuned current_goals_markers semantics: begin / end goal avoids
  8210 printing empty lines;
  8211 
  8212 * removed prs and prs_fn hook, which was broken because it did not
  8213 include \n in its semantics, forcing writeln to add one
  8214 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8215 string -> unit if you really want to output text without newline;
  8216 
  8217 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8218 plain output, interface builders may have to enable 'isabelle_font'
  8219 mode to get Isabelle font glyphs as before;
  8220 
  8221 * refined token_translation interface; INCOMPATIBILITY: output length
  8222 now of type real instead of int;
  8223 
  8224 * theory loader actions may be traced via new ThyInfo.add_hook
  8225 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8226 your own database of information attached to *whole* theories -- as
  8227 opposed to intra-theory data slots offered via TheoryDataFun;
  8228 
  8229 * proper handling of dangling sort hypotheses (at last!);
  8230 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8231 extra sort hypotheses that can be witnessed from the type signature;
  8232 the force_strip_shyps flag is gone, any remaining shyps are simply
  8233 left in the theorem (with a warning issued by strip_shyps_warning);
  8234 
  8235 
  8236 
  8237 New in Isabelle98-1 (October 1998)
  8238 ----------------------------------
  8239 
  8240 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8241 
  8242 * several changes of automated proof tools;
  8243 
  8244 * HOL: major changes to the inductive and datatype packages, including
  8245 some minor incompatibilities of theory syntax;
  8246 
  8247 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8248 called `inj_on';
  8249 
  8250 * HOL: removed duplicate thms in Arith:
  8251   less_imp_add_less  should be replaced by  trans_less_add1
  8252   le_imp_add_le      should be replaced by  trans_le_add1
  8253 
  8254 * HOL: unary minus is now overloaded (new type constraints may be
  8255 required);
  8256 
  8257 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8258 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8259 now taken as an integer constant.
  8260 
  8261 * Pure: ML function 'theory_of' renamed to 'theory';
  8262 
  8263 
  8264 *** Proof tools ***
  8265 
  8266 * Simplifier:
  8267   1. Asm_full_simp_tac is now more aggressive.
  8268      1. It will sometimes reorient premises if that increases their power to
  8269         simplify.
  8270      2. It does no longer proceed strictly from left to right but may also
  8271         rotate premises to achieve further simplification.
  8272      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8273      old Asm_full_simp_tac in that it does not rotate premises.
  8274   2. The simplifier now knows a little bit about nat-arithmetic.
  8275 
  8276 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8277 allows for selected deletion of wrappers, by introduction of names for
  8278 wrapper functionals.  This implies that addbefore, addSbefore,
  8279 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8280 and that adding two tactics with the same name overwrites the first
  8281 one (emitting a warning).
  8282   type wrapper = (int -> tactic) -> (int -> tactic)
  8283   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8284   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8285   delWrapper, delSWrapper: claset *  string            -> claset
  8286   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8287 
  8288 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8289 semantics; addbefore now affects only the unsafe part of step_tac
  8290 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8291 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8292 by Force_tac;
  8293 
  8294 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8295 compWrapper; added safe wrapper (and access functions for it);
  8296 
  8297 * HOL/split_all_tac is now much faster and fails if there is nothing
  8298 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8299 and the names of the automatically generated variables have changed.
  8300 split_all_tac has moved within claset() from unsafe wrappers to safe
  8301 wrappers, which means that !!-bound variables are split much more
  8302 aggressively, and safe_tac and clarify_tac now split such variables.
  8303 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8304 Note: the same holds for record_split_tac, which does the job of
  8305 split_all_tac for record fields.
  8306 
  8307 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8308 permanently to the default simpset using Addsplits just like
  8309 Addsimps. They can be removed via Delsplits just like
  8310 Delsimps. Lower-case versions are also available.
  8311 
  8312 * HOL/Simplifier: The rule split_if is now part of the default
  8313 simpset. This means that the simplifier will eliminate all occurrences
  8314 of if-then-else in the conclusion of a goal. To prevent this, you can
  8315 either remove split_if completely from the default simpset by
  8316 `Delsplits [split_if]' or remove it in a specific call of the
  8317 simplifier using `... delsplits [split_if]'.  You can also add/delete
  8318 other case splitting rules to/from the default simpset: every datatype
  8319 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  8320 t is the name of the datatype).
  8321 
  8322 * Classical reasoner / Simplifier combination: new force_tac (and
  8323 derivatives Force_tac, force) combines rewriting and classical
  8324 reasoning (and whatever other tools) similarly to auto_tac, but is
  8325 aimed to solve the given subgoal completely.
  8326 
  8327 
  8328 *** General ***
  8329 
  8330 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  8331 and `goalw': the theory is no longer needed as an explicit argument -
  8332 the current theory context is used; assumptions are no longer returned
  8333 at the ML-level unless one of them starts with ==> or !!; it is
  8334 recommended to convert to these new commands using isatool fixgoal
  8335 (backup your sources first!);
  8336 
  8337 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  8338 the current theory context, and 'theory' to lookup stored theories;
  8339 
  8340 * new theory section 'locale' for declaring constants, assumptions and
  8341 definitions that have local scope;
  8342 
  8343 * new theory section 'nonterminals' for purely syntactic types;
  8344 
  8345 * new theory section 'setup' for generic ML setup functions
  8346 (e.g. package initialization);
  8347 
  8348 * the distribution now includes Isabelle icons: see
  8349 lib/logo/isabelle-{small,tiny}.xpm;
  8350 
  8351 * isatool install - install binaries with absolute references to
  8352 ISABELLE_HOME/bin;
  8353 
  8354 * isatool logo -- create instances of the Isabelle logo (as EPS);
  8355 
  8356 * print mode 'emacs' reserved for Isamode;
  8357 
  8358 * support multiple print (ast) translations per constant name;
  8359 
  8360 * theorems involving oracles are now printed with a suffixed [!];
  8361 
  8362 
  8363 *** HOL ***
  8364 
  8365 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  8366 
  8367 * HOL/inductive package reorganized and improved: now supports mutual
  8368 definitions such as
  8369 
  8370   inductive EVEN ODD
  8371     intrs
  8372       null "0 : EVEN"
  8373       oddI "n : EVEN ==> Suc n : ODD"
  8374       evenI "n : ODD ==> Suc n : EVEN"
  8375 
  8376 new theorem list "elims" contains an elimination rule for each of the
  8377 recursive sets; inductive definitions now handle disjunctive premises
  8378 correctly (also ZF);
  8379 
  8380 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  8381 "mutual_induct" no longer exists - the induction rule is always
  8382 contained in "induct";
  8383 
  8384 
  8385 * HOL/datatype package re-implemented and greatly improved: now
  8386 supports mutually recursive datatypes such as
  8387 
  8388   datatype
  8389     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  8390             | SUM ('a aexp) ('a aexp)
  8391             | DIFF ('a aexp) ('a aexp)
  8392             | NUM 'a
  8393   and
  8394     'a bexp = LESS ('a aexp) ('a aexp)
  8395             | AND ('a bexp) ('a bexp)
  8396             | OR ('a bexp) ('a bexp)
  8397 
  8398 as well as indirectly recursive datatypes such as
  8399 
  8400   datatype
  8401     ('a, 'b) term = Var 'a
  8402                   | App 'b ((('a, 'b) term) list)
  8403 
  8404 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  8405 induction on mutually / indirectly recursive datatypes.
  8406 
  8407 Primrec equations are now stored in theory and can be accessed via
  8408 <function_name>.simps.
  8409 
  8410 INCOMPATIBILITIES:
  8411 
  8412   - Theories using datatypes must now have theory Datatype as an
  8413     ancestor.
  8414   - The specific <typename>.induct_tac no longer exists - use the
  8415     generic induct_tac instead.
  8416   - natE has been renamed to nat.exhaust - use exhaust_tac
  8417     instead of res_inst_tac ... natE. Note that the variable
  8418     names in nat.exhaust differ from the names in natE, this
  8419     may cause some "fragile" proofs to fail.
  8420   - The theorems split_<typename>_case and split_<typename>_case_asm
  8421     have been renamed to <typename>.split and <typename>.split_asm.
  8422   - Since default sorts of type variables are now handled correctly,
  8423     some datatype definitions may have to be annotated with explicit
  8424     sort constraints.
  8425   - Primrec definitions no longer require function name and type
  8426     of recursive argument.
  8427 
  8428 Consider using isatool fixdatatype to adapt your theories and proof
  8429 scripts to the new package (backup your sources first!).
  8430 
  8431 
  8432 * HOL/record package: considerably improved implementation; now
  8433 includes concrete syntax for record types, terms, updates; theorems
  8434 for surjective pairing and splitting !!-bound record variables; proof
  8435 support is as follows:
  8436 
  8437   1) standard conversions (selectors or updates applied to record
  8438 constructor terms) are part of the standard simpset;
  8439 
  8440   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  8441 made part of standard simpset and claset via addIffs;
  8442 
  8443   3) a tactic for record field splitting (record_split_tac) is part of
  8444 the standard claset (addSWrapper);
  8445 
  8446 To get a better idea about these rules you may retrieve them via
  8447 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  8448 the name of your record type.
  8449 
  8450 The split tactic 3) conceptually simplifies by the following rule:
  8451 
  8452   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  8453 
  8454 Thus any record variable that is bound by meta-all will automatically
  8455 blow up into some record constructor term, consequently the
  8456 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  8457 solve record problems automatically.
  8458 
  8459 
  8460 * reorganized the main HOL image: HOL/Integ and String loaded by
  8461 default; theory Main includes everything;
  8462 
  8463 * automatic simplification of integer sums and comparisons, using cancellation;
  8464 
  8465 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  8466 
  8467 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  8468 
  8469 * many new identities for unions, intersections, set difference, etc.;
  8470 
  8471 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  8472 called split_if, split_split, split_sum_case and split_nat_case (to go
  8473 with add/delsplits);
  8474 
  8475 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  8476 (?x::unit) = (); this is made part of the default simpset, which COULD
  8477 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  8478 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  8479 unit_abs_eta_conv is added in order to counter the effect of
  8480 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  8481 %u.f();
  8482 
  8483 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  8484 makes more sense);
  8485 
  8486 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8487   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8488   disjointness reasoning but breaking a few old proofs.
  8489 
  8490 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  8491 to 'converse' from 'inverse' (for compatibility with ZF and some
  8492 literature);
  8493 
  8494 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  8495 the well-founded relation;
  8496 
  8497 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8498     Compl A.  The "Compl" syntax remains available as input syntax for this
  8499     release ONLY.
  8500 
  8501 * HOL/Update: new theory of function updates:
  8502     f(a:=b) == %x. if x=a then b else f x
  8503 may also be iterated as in f(a:=b,c:=d,...);
  8504 
  8505 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8506 
  8507 * HOL/List:
  8508   - new function list_update written xs[i:=v] that updates the i-th
  8509     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8510   - new function `upt' written [i..j(] which generates the list
  8511     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8512     bound write [i..j], which is a shorthand for [i..j+1(].
  8513   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8514 
  8515 * HOL/Arith:
  8516   - removed 'pred' (predecessor) function;
  8517   - generalized some theorems about n-1;
  8518   - many new laws about "div" and "mod";
  8519   - new laws about greatest common divisors (see theory ex/Primes);
  8520 
  8521 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8522 instead of "inverse";
  8523 
  8524 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8525   of the multiset ordering;
  8526 
  8527 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8528   (not included by default);
  8529 
  8530 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8531 
  8532 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8533   programs, i.e. different program variables may have different types.
  8534 
  8535 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8536   [previously, this check worked only if the rewrite rule was unconditional]
  8537   Now rew can involve either definitions or equalities (either == or =).
  8538 
  8539 
  8540 *** ZF ***
  8541 
  8542 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8543   only the theorems proved on ZF.ML;
  8544 
  8545 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8546   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8547   disjointness reasoning but breaking a few old proofs.
  8548 
  8549 * ZF/Update: new theory of function updates
  8550     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8551   may also be iterated as in f(a:=b,c:=d,...);
  8552 
  8553 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8554 
  8555 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8556   [previously, this check worked only if the rewrite rule was unconditional]
  8557   Now rew can involve either definitions or equalities (either == or =).
  8558 
  8559 * case_tac provided for compatibility with HOL
  8560     (like the old excluded_middle_tac, but with subgoals swapped)
  8561 
  8562 
  8563 *** Internal programming interfaces ***
  8564 
  8565 * Pure: several new basic modules made available for general use, see
  8566 also src/Pure/README;
  8567 
  8568 * improved the theory data mechanism to support encapsulation (data
  8569 kind name replaced by private Object.kind, acting as authorization
  8570 key); new type-safe user interface via functor TheoryDataFun; generic
  8571 print_data function becomes basically useless;
  8572 
  8573 * removed global_names compatibility flag -- all theory declarations
  8574 are qualified by default;
  8575 
  8576 * module Pure/Syntax now offers quote / antiquote translation
  8577 functions (useful for Hoare logic etc. with implicit dependencies);
  8578 see HOL/ex/Antiquote for an example use;
  8579 
  8580 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8581 cterm -> thm;
  8582 
  8583 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8584 subgoal;
  8585 
  8586 * Display.print_goals function moved to Locale.print_goals;
  8587 
  8588 * standard print function for goals supports current_goals_markers
  8589 variable for marking begin of proof, end of proof, start of goal; the
  8590 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8591 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8592 for example;
  8593 
  8594 
  8595 
  8596 New in Isabelle98 (January 1998)
  8597 --------------------------------
  8598 
  8599 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8600 
  8601 * changed lexical syntax of terms / types: dots made part of long
  8602 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8603 
  8604 * simpset (and claset) reference variable replaced by functions
  8605 simpset / simpset_ref;
  8606 
  8607 * no longer supports theory aliases (via merge) and non-trivial
  8608 implicit merge of thms' signatures;
  8609 
  8610 * most internal names of constants changed due to qualified names;
  8611 
  8612 * changed Pure/Sequence interface (see Pure/seq.ML);
  8613 
  8614 
  8615 *** General Changes ***
  8616 
  8617 * hierachically structured name spaces (for consts, types, axms, thms
  8618 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8619 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8620 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8621 long_names for fully qualified output names; NOTE: ML programs
  8622 (special tactics, packages etc.) referring to internal names may have
  8623 to be adapted to cope with fully qualified names; in case of severe
  8624 backward campatibility problems try setting 'global_names' at compile
  8625 time to have enrything declared within a flat name space; one may also
  8626 fine tune name declarations in theories via the 'global' and 'local'
  8627 section;
  8628 
  8629 * reimplemented the implicit simpset and claset using the new anytype
  8630 data filed in signatures; references simpset:simpset ref etc. are
  8631 replaced by functions simpset:unit->simpset and
  8632 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8633 to patch your ML files accordingly;
  8634 
  8635 * HTML output now includes theory graph data for display with Java
  8636 applet or isatool browser; data generated automatically via isatool
  8637 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8638 
  8639 * defs may now be conditional; improved rewrite_goals_tac to handle
  8640 conditional equations;
  8641 
  8642 * defs now admits additional type arguments, using TYPE('a) syntax;
  8643 
  8644 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8645 creates a new theory node; implicit merge of thms' signatures is
  8646 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8647 transfer:theory->thm->thm in (rare) cases;
  8648 
  8649 * improved handling of draft signatures / theories; draft thms (and
  8650 ctyps, cterms) are automatically promoted to real ones;
  8651 
  8652 * slightly changed interfaces for oracles: admit many per theory, named
  8653 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8654 
  8655 * print_goals: optional output of const types (set show_consts and
  8656 show_types);
  8657 
  8658 * improved output of warnings (###) and errors (***);
  8659 
  8660 * subgoal_tac displays a warning if the new subgoal has type variables;
  8661 
  8662 * removed old README and Makefiles;
  8663 
  8664 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8665 
  8666 * removed obsolete init_pps and init_database;
  8667 
  8668 * deleted the obsolete tactical STATE, which was declared by
  8669     fun STATE tacfun st = tacfun st st;
  8670 
  8671 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8672 (which abbreviates $HOME);
  8673 
  8674 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8675 use isatool fixseq to adapt your ML programs (this works for fully
  8676 qualified references to the Sequence structure only!);
  8677 
  8678 * use_thy no longer requires writable current directory; it always
  8679 reloads .ML *and* .thy file, if either one is out of date;
  8680 
  8681 
  8682 *** Classical Reasoner ***
  8683 
  8684 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8685 tactics that use classical reasoning to simplify a subgoal without
  8686 splitting it into several subgoals;
  8687 
  8688 * Safe_tac: like safe_tac but uses the default claset;
  8689 
  8690 
  8691 *** Simplifier ***
  8692 
  8693 * added simplification meta rules:
  8694     (asm_)(full_)simplify: simpset -> thm -> thm;
  8695 
  8696 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8697 logics (again);
  8698 
  8699 * added prems argument to simplification procedures;
  8700 
  8701 * HOL, FOL, ZF: added infix function `addsplits':
  8702   instead of `<simpset> setloop (split_tac <thms>)'
  8703   you can simply write `<simpset> addsplits <thms>'
  8704 
  8705 
  8706 *** Syntax ***
  8707 
  8708 * TYPE('a) syntax for type reflection terms;
  8709 
  8710 * no longer handles consts with name "" -- declare as 'syntax' instead;
  8711 
  8712 * pretty printer: changed order of mixfix annotation preference (again!);
  8713 
  8714 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  8715 
  8716 
  8717 *** HOL ***
  8718 
  8719 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8720   with `addloop' of the simplifier to faciliate case splitting in premises.
  8721 
  8722 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  8723 
  8724 * HOL/Auth: new protocol proofs including some for the Internet
  8725   protocol TLS;
  8726 
  8727 * HOL/Map: new theory of `maps' a la VDM;
  8728 
  8729 * HOL/simplifier: simplification procedures nat_cancel_sums for
  8730 cancelling out common nat summands from =, <, <= (in)equalities, or
  8731 differences; simplification procedures nat_cancel_factor for
  8732 cancelling common factor from =, <, <= (in)equalities over natural
  8733 sums; nat_cancel contains both kinds of procedures, it is installed by
  8734 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  8735 
  8736 * HOL/simplifier: terms of the form
  8737   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  8738   are rewritten to
  8739   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  8740   and those of the form
  8741   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  8742   are rewritten to
  8743   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  8744 
  8745 * HOL/datatype
  8746   Each datatype `t' now comes with a theorem `split_t_case' of the form
  8747 
  8748   P(t_case f1 ... fn x) =
  8749      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  8750         ...
  8751        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  8752      )
  8753 
  8754   and a theorem `split_t_case_asm' of the form
  8755 
  8756   P(t_case f1 ... fn x) =
  8757     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  8758         ...
  8759        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  8760      )
  8761   which can be added to a simpset via `addsplits'. The existing theorems
  8762   expand_list_case and expand_option_case have been renamed to
  8763   split_list_case and split_option_case.
  8764 
  8765 * HOL/Arithmetic:
  8766   - `pred n' is automatically converted to `n-1'.
  8767     Users are strongly encouraged not to use `pred' any longer,
  8768     because it will disappear altogether at some point.
  8769   - Users are strongly encouraged to write "0 < n" rather than
  8770     "n ~= 0". Theorems and proof tools have been modified towards this
  8771     `standard'.
  8772 
  8773 * HOL/Lists:
  8774   the function "set_of_list" has been renamed "set" (and its theorems too);
  8775   the function "nth" now takes its arguments in the reverse order and
  8776   has acquired the infix notation "!" as in "xs!n".
  8777 
  8778 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  8779 
  8780 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  8781   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  8782 
  8783 * HOL/record: extensible records with schematic structural subtyping
  8784 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  8785 still lacks various theorems and concrete record syntax;
  8786 
  8787 
  8788 *** HOLCF ***
  8789 
  8790 * removed "axioms" and "generated by" sections;
  8791 
  8792 * replaced "ops" section by extended "consts" section, which is capable of
  8793   handling the continuous function space "->" directly;
  8794 
  8795 * domain package:
  8796   . proves theorems immediately and stores them in the theory,
  8797   . creates hierachical name space,
  8798   . now uses normal mixfix annotations (instead of cinfix...),
  8799   . minor changes to some names and values (for consistency),
  8800   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  8801   . separator between mutual domain defs: changed "," to "and",
  8802   . improved handling of sort constraints;  now they have to
  8803     appear on the left-hand side of the equations only;
  8804 
  8805 * fixed LAM <x,y,zs>.b syntax;
  8806 
  8807 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  8808 adm (%x. P (t x)), where P is chainfinite and t continuous;
  8809 
  8810 
  8811 *** FOL and ZF ***
  8812 
  8813 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8814   with `addloop' of the simplifier to faciliate case splitting in premises.
  8815 
  8816 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  8817 in HOL, they strip ALL and --> from proved theorems;
  8818 
  8819 
  8820 
  8821 New in Isabelle94-8 (May 1997)
  8822 ------------------------------
  8823 
  8824 *** General Changes ***
  8825 
  8826 * new utilities to build / run / maintain Isabelle etc. (in parts
  8827 still somewhat experimental); old Makefiles etc. still functional;
  8828 
  8829 * new 'Isabelle System Manual';
  8830 
  8831 * INSTALL text, together with ./configure and ./build scripts;
  8832 
  8833 * reimplemented type inference for greater efficiency, better error
  8834 messages and clean internal interface;
  8835 
  8836 * prlim command for dealing with lots of subgoals (an easier way of
  8837 setting goals_limit);
  8838 
  8839 
  8840 *** Syntax ***
  8841 
  8842 * supports alternative (named) syntax tables (parser and pretty
  8843 printer); internal interface is provided by add_modesyntax(_i);
  8844 
  8845 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  8846 be used in conjunction with the Isabelle symbol font; uses the
  8847 "symbols" syntax table;
  8848 
  8849 * added token_translation interface (may translate name tokens in
  8850 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  8851 the current print_mode); IMPORTANT: user print translation functions
  8852 are responsible for marking newly introduced bounds
  8853 (Syntax.mark_boundT);
  8854 
  8855 * token translations for modes "xterm" and "xterm_color" that display
  8856 names in bold, underline etc. or colors (which requires a color
  8857 version of xterm);
  8858 
  8859 * infixes may now be declared with names independent of their syntax;
  8860 
  8861 * added typed_print_translation (like print_translation, but may
  8862 access type of constant);
  8863 
  8864 
  8865 *** Classical Reasoner ***
  8866 
  8867 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  8868 some limitations.  Blast_tac...
  8869   + ignores addss, addbefore, addafter; this restriction is intrinsic
  8870   + ignores elimination rules that don't have the correct format
  8871         (the conclusion MUST be a formula variable)
  8872   + ignores types, which can make HOL proofs fail
  8873   + rules must not require higher-order unification, e.g. apply_type in ZF
  8874     [message "Function Var's argument not a bound variable" relates to this]
  8875   + its proof strategy is more general but can actually be slower
  8876 
  8877 * substitution with equality assumptions no longer permutes other
  8878 assumptions;
  8879 
  8880 * minor changes in semantics of addafter (now called addaltern); renamed
  8881 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  8882 (and access functions for it);
  8883 
  8884 * improved combination of classical reasoner and simplifier:
  8885   + functions for handling clasimpsets
  8886   + improvement of addss: now the simplifier is called _after_ the
  8887     safe steps.
  8888   + safe variant of addss called addSss: uses safe simplifications
  8889     _during_ the safe steps. It is more complete as it allows multiple
  8890     instantiations of unknowns (e.g. with slow_tac).
  8891 
  8892 *** Simplifier ***
  8893 
  8894 * added interface for simplification procedures (functions that
  8895 produce *proven* rewrite rules on the fly, depending on current
  8896 redex);
  8897 
  8898 * ordering on terms as parameter (used for ordered rewriting);
  8899 
  8900 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  8901 
  8902 * the solver is now split into a safe and an unsafe part.
  8903 This should be invisible for the normal user, except that the
  8904 functions setsolver and addsolver have been renamed to setSolver and
  8905 addSolver; added safe_asm_full_simp_tac;
  8906 
  8907 
  8908 *** HOL ***
  8909 
  8910 * a generic induction tactic `induct_tac' which works for all datatypes and
  8911 also for type `nat';
  8912 
  8913 * a generic case distinction tactic `exhaust_tac' which works for all
  8914 datatypes and also for type `nat';
  8915 
  8916 * each datatype comes with a function `size';
  8917 
  8918 * patterns in case expressions allow tuple patterns as arguments to
  8919 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  8920 
  8921 * primrec now also works with type nat;
  8922 
  8923 * recdef: a new declaration form, allows general recursive functions to be
  8924 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  8925 
  8926 * the constant for negation has been renamed from "not" to "Not" to
  8927 harmonize with FOL, ZF, LK, etc.;
  8928 
  8929 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  8930 infinite lists;
  8931 
  8932 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  8933 
  8934 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  8935 problems in commutative rings, using axiomatic type classes for + and *;
  8936 
  8937 * more examples in HOL/MiniML and HOL/Auth;
  8938 
  8939 * more default rewrite rules for quantifiers, union/intersection;
  8940 
  8941 * a new constant `arbitrary == @x.False';
  8942 
  8943 * HOLCF/IOA replaces old HOL/IOA;
  8944 
  8945 * HOLCF changes: derived all rules and arities
  8946   + axiomatic type classes instead of classes
  8947   + typedef instead of faking type definitions
  8948   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  8949   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  8950   + eliminated the types void, one, tr
  8951   + use unit lift and bool lift (with translations) instead of one and tr
  8952   + eliminated blift from Lift3.thy (use Def instead of blift)
  8953   all eliminated rules are derived as theorems --> no visible changes ;
  8954 
  8955 
  8956 *** ZF ***
  8957 
  8958 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  8959 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  8960 as ZF_cs addSIs [equalityI];
  8961 
  8962 
  8963 
  8964 New in Isabelle94-7 (November 96)
  8965 ---------------------------------
  8966 
  8967 * allowing negative levels (as offsets) in prlev and choplev;
  8968 
  8969 * super-linear speedup for large simplifications;
  8970 
  8971 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  8972 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  8973 FAIL); can suppress it using the command Delsimps (ex_simps @
  8974 all_simps); De Morgan laws are also now included, by default;
  8975 
  8976 * improved printing of ==>  :  ~:
  8977 
  8978 * new object-logic "Sequents" adds linear logic, while replacing LK
  8979 and Modal (thanks to Sara Kalvala);
  8980 
  8981 * HOL/Auth: correctness proofs for authentication protocols;
  8982 
  8983 * HOL: new auto_tac combines rewriting and classical reasoning (many
  8984 examples on HOL/Auth);
  8985 
  8986 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  8987 the rewriter and classical reasoner simultaneously;
  8988 
  8989 * function uresult no longer returns theorems in "standard" format;
  8990 regain previous version by: val uresult = standard o uresult;
  8991 
  8992 
  8993 
  8994 New in Isabelle94-6
  8995 -------------------
  8996 
  8997 * oracles -- these establish an interface between Isabelle and trusted
  8998 external reasoners, which may deliver results as theorems;
  8999 
  9000 * proof objects (in particular record all uses of oracles);
  9001 
  9002 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  9003 
  9004 * "constdefs" section in theory files;
  9005 
  9006 * "primrec" section (HOL) no longer requires names;
  9007 
  9008 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  9009 
  9010 
  9011 
  9012 New in Isabelle94-5
  9013 -------------------
  9014 
  9015 * reduced space requirements;
  9016 
  9017 * automatic HTML generation from theories;
  9018 
  9019 * theory files no longer require "..." (quotes) around most types;
  9020 
  9021 * new examples, including two proofs of the Church-Rosser theorem;
  9022 
  9023 * non-curried (1994) version of HOL is no longer distributed;
  9024 
  9025 
  9026 
  9027 New in Isabelle94-4
  9028 -------------------
  9029 
  9030 * greatly reduced space requirements;
  9031 
  9032 * theory files (.thy) no longer require \...\ escapes at line breaks;
  9033 
  9034 * searchable theorem database (see the section "Retrieving theorems" on
  9035 page 8 of the Reference Manual);
  9036 
  9037 * new examples, including Grabczewski's monumental case study of the
  9038 Axiom of Choice;
  9039 
  9040 * The previous version of HOL renamed to Old_HOL;
  9041 
  9042 * The new version of HOL (previously called CHOL) uses a curried syntax
  9043 for functions.  Application looks like f a b instead of f(a,b);
  9044 
  9045 * Mutually recursive inductive definitions finally work in HOL;
  9046 
  9047 * In ZF, pattern-matching on tuples is now available in all abstractions and
  9048 translates to the operator "split";
  9049 
  9050 
  9051 
  9052 New in Isabelle94-3
  9053 -------------------
  9054 
  9055 * new infix operator, addss, allowing the classical reasoner to
  9056 perform simplification at each step of its search.  Example:
  9057         fast_tac (cs addss ss)
  9058 
  9059 * a new logic, CHOL, the same as HOL, but with a curried syntax
  9060 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  9061 look like (a,b) instead of <a,b>;
  9062 
  9063 * PLEASE NOTE: CHOL will eventually replace HOL!
  9064 
  9065 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  9066 It translates to the operator "split".  A new theory of integers is available;
  9067 
  9068 * In ZF, integer numerals now denote two's-complement binary integers.
  9069 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  9070 
  9071 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  9072 of the Axiom of Choice;
  9073 
  9074 
  9075 
  9076 New in Isabelle94-2
  9077 -------------------
  9078 
  9079 * Significantly faster resolution;
  9080 
  9081 * the different sections in a .thy file can now be mixed and repeated
  9082 freely;
  9083 
  9084 * Database of theorems for FOL, HOL and ZF.  New
  9085 commands including qed, qed_goal and bind_thm store theorems in the database.
  9086 
  9087 * Simple database queries: return a named theorem (get_thm) or all theorems of
  9088 a given theory (thms_of), or find out what theory a theorem was proved in
  9089 (theory_of_thm);
  9090 
  9091 * Bugs fixed in the inductive definition and datatype packages;
  9092 
  9093 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  9094 and HOL_dup_cs obsolete;
  9095 
  9096 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  9097 have been removed;
  9098 
  9099 * Simpler definition of function space in ZF;
  9100 
  9101 * new results about cardinal and ordinal arithmetic in ZF;
  9102 
  9103 * 'subtype' facility in HOL for introducing new types as subsets of existing
  9104 types;
  9105 
  9106 :mode=text:wrap=hard:maxLineLen=72: