NEWS
author huffman
Tue, 27 Mar 2012 15:34:36 +0200
changeset 48032 8a32c2294498
parent 48031 8ada79014cb2
child 48033 9d7d919b9fd8
permissions -rw-r--r--
remove duplicate [algebra] declarations
     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 * ISABELLE_JDK_HOME settings variable points to JDK with javac and jar
    49 (not just JRE), derived from JAVA_HOME from the shell environment or
    50 java.home of the running JVM.
    51 
    52 
    53 *** Pure ***
    54 
    55 * Command 'definition' no longer exports the foundational "raw_def"
    56 into the user context.  Minor INCOMPATIBILITY, may use the regular
    57 "def" result with attribute "abs_def" to imitate the old version.
    58 
    59 * Attribute "abs_def" turns an equation of the form "f x y == t" into
    60 "f == %x y. t", which ensures that "simp" or "unfold" steps always
    61 expand it.  This also works for object-logic equality.  (Formerly
    62 undocumented feature.)
    63 
    64 * Discontinued old "prems" fact, which used to refer to the accidental
    65 collection of foundational premises in the context (marked as legacy
    66 since Isabelle2011).
    67 
    68 * Obsolete command 'types' has been discontinued.  Use 'type_synonym'
    69 instead.  INCOMPATIBILITY.
    70 
    71 * Ancient code generator for SML and its commands 'code_module',
    72 'code_library', 'consts_code', 'types_code' have been discontinued.
    73 Use commands of the generic code generator instead.  INCOMPATIBILITY.
    74 
    75 * Redundant attribute 'code_inline' has been discontinued. Use
    76 'code_unfold' instead.  INCOMPATIBILITY.
    77 
    78 * Dropped attribute 'code_unfold_post' in favor of the its dual
    79 'code_abbrev', which yields a common pattern in definitions like
    80 
    81   definition [code_abbrev]: "f = t"
    82 
    83 INCOMPATIBILITY.
    84 
    85 * Sort constraints are now propagated in simultaneous statements, just
    86 like type constraints.  INCOMPATIBILITY in rare situations, where
    87 distinct sorts used to be assigned accidentally.  For example:
    88 
    89   lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"
    90 
    91   lemma "P (x::'a)" and "Q (y::'a::bar)"
    92     -- "now uniform 'a::bar instead of default sort for first occurence (!)"
    93 
    94 
    95 *** HOL ***
    96 
    97 * The representation of numerals has changed. We now have a datatype
    98 "num" representing strictly positive binary numerals, along with
    99 functions "numeral :: num => 'a" and "neg_numeral :: num => 'a" to
   100 represent positive and negated numeric literals, respectively. (See
   101 definitions in Num.thy.) Potential INCOMPATIBILITY; some user theories
   102 may require adaptations:
   103 
   104   - Theorems with number_ring or number_semiring constraints: These
   105     classes are gone; use comm_ring_1 or comm_semiring_1 instead.
   106 
   107   - Theories defining numeric types: Remove number, number_semiring,
   108     and number_ring instances. Defer all theorems about numerals until
   109     after classes one and semigroup_add have been instantiated.
   110 
   111   - Numeral-only simp rules: Replace each rule having a "number_of v"
   112     pattern with two copies, one for numeral and one for neg_numeral.
   113 
   114   - Theorems about subclasses of semiring_1 or ring_1: These classes
   115     automatically support numerals now, so more simp rules and
   116     simprocs may now apply within the proof.
   117 
   118   - Definitions and theorems using old constructors Pls/Min/Bit0/Bit1:
   119     Redefine using other integer operations.
   120 
   121 * Type 'a set is now a proper type constructor (just as before
   122 Isabelle2008).  Definitions mem_def and Collect_def have disappeared.
   123 Non-trivial INCOMPATIBILITY.  For developments keeping predicates and
   124 sets separate, it is often sufficient to rephrase sets S accidentally
   125 used as predicates by "%x. x : S" and predicates P accidentally used
   126 as sets by "{x. P x}".  Corresponding proofs in a first step should be
   127 pruned from any tinkering with former theorems mem_def and
   128 Collect_def as far as possible.
   129 For developments which deliberately mixed predicates and
   130 sets, a planning step is necessary to determine what should become a
   131 predicate and what a set.  It can be helpful to carry out that step in
   132 Isabelle2011-1 before jumping right into the current release.
   133 
   134 * Code generation by default implements sets as container type rather
   135 than predicates.  INCOMPATIBILITY.
   136 
   137 * New type synonym 'a rel = ('a * 'a) set
   138 
   139 * Theory Divides: Discontinued redundant theorems about div and mod.
   140 INCOMPATIBILITY, use the corresponding generic theorems instead.
   141 
   142   DIVISION_BY_ZERO ~> div_by_0, mod_by_0
   143   zdiv_self ~> div_self
   144   zmod_self ~> mod_self
   145   zdiv_zero ~> div_0
   146   zmod_zero ~> mod_0
   147   zmod_zdiv_trivial ~> mod_div_trivial
   148   zdiv_zminus_zminus ~> div_minus_minus
   149   zmod_zminus_zminus ~> mod_minus_minus
   150   zdiv_zminus2 ~> div_minus_right
   151   zmod_zminus2 ~> mod_minus_right
   152   zdiv_minus1_right ~> div_minus1_right
   153   zmod_minus1_right ~> mod_minus1_right
   154   mod_mult_distrib ~> mult_mod_left
   155   mod_mult_distrib2 ~> mult_mod_right
   156 
   157 * More default pred/set conversions on a couple of relation operations
   158 and predicates.  Consolidation of some relation theorems:
   159 
   160   converse_def ~> converse_unfold
   161   rel_comp_def ~> rel_comp_unfold
   162   symp_def ~> (dropped, use symp_def and sym_def instead)
   163   transp_def ~> transp_trans
   164   Domain_def ~> Domain_unfold
   165   Range_def ~> Domain_converse [symmetric]
   166 
   167 Generalized theorems INF_INT_eq, INF_INT_eq2, SUP_UN_eq, SUP_UN_eq2.
   168 
   169 See theory "Relation" for examples for making use of pred/set conversions
   170 by means of attributes "to_set" and "to_pred".
   171 
   172 INCOMPATIBILITY.
   173 
   174 * Consolidated various theorem names relating to Finite_Set.fold
   175 combinator:
   176 
   177   inf_INFI_fold_inf ~> inf_INF_fold_inf
   178   sup_SUPR_fold_sup ~> sup_SUP_fold_sup
   179   INFI_fold_inf ~> INF_fold_inf
   180   SUPR_fold_sup ~> SUP_fold_sup
   181   union_set ~> union_set_fold
   182   minus_set ~> minus_set_fold
   183 
   184 INCOMPATIBILITY.
   185 
   186 * Consolidated theorem names concerning fold combinators:
   187 
   188   INFI_set_fold ~> INF_set_fold
   189   SUPR_set_fold ~> SUP_set_fold
   190   INF_code ~> INF_set_foldr
   191   SUP_code ~> SUP_set_foldr
   192   foldr.simps ~> foldr_Nil foldr_Cons (in point-free formulation)
   193   foldl.simps ~> foldl_Nil foldl_Cons
   194   foldr_fold_rev ~> foldr_def
   195   foldl_fold ~> foldl_def
   196 
   197 INCOMPATIBILITY.
   198 
   199 * Dropped rarely useful theorems concerning fold combinators:
   200 foldl_apply, foldl_fun_comm, foldl_rev, fold_weak_invariant,
   201 rev_foldl_cons, fold_set_remdups, fold_set, fold_set1,
   202 concat_conv_foldl, foldl_weak_invariant, foldl_invariant,
   203 foldr_invariant, foldl_absorb0, foldl_foldr1_lemma, foldl_foldr1,
   204 listsum_conv_fold, listsum_foldl, sort_foldl_insort.  INCOMPATIBILITY.
   205 Prefer "List.fold" with canonical argument order, or boil down
   206 "List.foldr" and "List.foldl" to "List.fold" by unfolding "foldr_def"
   207 and "foldl_def".  For the common phrases "%xs. List.foldr plus xs 0"
   208 and "List.foldl plus 0", prefer "List.listsum".
   209 
   210 * Congruence rules Option.map_cong and Option.bind_cong for recursion
   211 through option types.
   212 
   213 * Concrete syntax for case expressions includes constraints for source
   214 positions, and thus produces Prover IDE markup for its bindings.
   215 INCOMPATIBILITY for old-style syntax translations that augment the
   216 pattern notation; e.g. see src/HOL/HOLCF/One.thy for translations of
   217 one_case.
   218 
   219 * Discontinued configuration option "syntax_positions": atomic terms
   220 in parse trees are always annotated by position constraints.
   221 
   222 * Finite_Set.fold now qualified.  INCOMPATIBILITY.
   223 
   224 * Renamed some facts on canonical fold on lists, in order to avoid
   225 problems with interpretation involving corresponding facts on foldl
   226 with the same base names:
   227 
   228   fold_set_remdups ~> fold_set_fold_remdups
   229   fold_set ~> fold_set_fold
   230   fold1_set ~> fold1_set_fold
   231 
   232 INCOMPATIBILITY.
   233 
   234 * Renamed facts about the power operation on relations, i.e., relpow
   235   to match the constant's name:
   236   
   237   rel_pow_1 ~> relpow_1
   238   rel_pow_0_I ~> relpow_0_I
   239   rel_pow_Suc_I ~> relpow_Suc_I
   240   rel_pow_Suc_I2 ~> relpow_Suc_I2
   241   rel_pow_0_E ~> relpow_0_E
   242   rel_pow_Suc_E ~> relpow_Suc_E
   243   rel_pow_E ~> relpow_E
   244   rel_pow_Suc_D2 ~> relpow_Suc_D2
   245   rel_pow_Suc_E2 ~> relpow_Suc_E2 
   246   rel_pow_Suc_D2' ~> relpow_Suc_D2'
   247   rel_pow_E2 ~> relpow_E2
   248   rel_pow_add ~> relpow_add
   249   rel_pow_commute ~> relpow
   250   rel_pow_empty ~> relpow_empty:
   251   rtrancl_imp_UN_rel_pow ~> rtrancl_imp_UN_relpow
   252   rel_pow_imp_rtrancl ~> relpow_imp_rtrancl
   253   rtrancl_is_UN_rel_pow ~> rtrancl_is_UN_relpow
   254   rtrancl_imp_rel_pow ~> rtrancl_imp_relpow
   255   rel_pow_fun_conv ~> relpow_fun_conv
   256   rel_pow_finite_bounded1 ~> relpow_finite_bounded1
   257   rel_pow_finite_bounded ~> relpow_finite_bounded
   258   rtrancl_finite_eq_rel_pow ~> rtrancl_finite_eq_relpow
   259   trancl_finite_eq_rel_pow ~> trancl_finite_eq_relpow
   260   single_valued_rel_pow ~> single_valued_relpow
   261  
   262 INCOMPATIBILITY.
   263 
   264 * New theory HOL/Library/DAList provides an abstract type for association
   265   lists with distinct keys.
   266 
   267 * 'datatype' specifications allow explicit sort constraints.
   268 
   269 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY,
   270 use theory HOL/Library/Nat_Bijection instead.
   271 
   272 * Session HOL-Word: Discontinued many redundant theorems specific to
   273 type 'a word. INCOMPATIBILITY, use the corresponding generic theorems
   274 instead.
   275 
   276   word_sub_alt ~> word_sub_wi
   277   word_add_alt ~> word_add_def
   278   word_mult_alt ~> word_mult_def
   279   word_minus_alt ~> word_minus_def
   280   word_0_alt ~> word_0_wi
   281   word_1_alt ~> word_1_wi
   282   word_add_0 ~> add_0_left
   283   word_add_0_right ~> add_0_right
   284   word_mult_1 ~> mult_1_left
   285   word_mult_1_right ~> mult_1_right
   286   word_add_commute ~> add_commute
   287   word_add_assoc ~> add_assoc
   288   word_add_left_commute ~> add_left_commute
   289   word_mult_commute ~> mult_commute
   290   word_mult_assoc ~> mult_assoc
   291   word_mult_left_commute ~> mult_left_commute
   292   word_left_distrib ~> left_distrib
   293   word_right_distrib ~> right_distrib
   294   word_left_minus ~> left_minus
   295   word_diff_0_right ~> diff_0_right
   296   word_diff_self ~> diff_self
   297   word_sub_def ~> diff_minus
   298   word_diff_minus ~> diff_minus
   299   word_add_ac ~> add_ac
   300   word_mult_ac ~> mult_ac
   301   word_plus_ac0 ~> add_0_left add_0_right add_ac
   302   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
   303   word_order_trans ~> order_trans
   304   word_order_refl ~> order_refl
   305   word_order_antisym ~> order_antisym
   306   word_order_linear ~> linorder_linear
   307   lenw1_zero_neq_one ~> zero_neq_one
   308   word_number_of_eq ~> number_of_eq
   309   word_of_int_add_hom ~> wi_hom_add
   310   word_of_int_sub_hom ~> wi_hom_sub
   311   word_of_int_mult_hom ~> wi_hom_mult
   312   word_of_int_minus_hom ~> wi_hom_neg
   313   word_of_int_succ_hom ~> wi_hom_succ
   314   word_of_int_pred_hom ~> wi_hom_pred
   315   word_of_int_0_hom ~> word_0_wi
   316   word_of_int_1_hom ~> word_1_wi
   317 
   318 * Clarified attribute "mono_set": pure declaration without modifying
   319 the result of the fact expression.
   320 
   321 * "Transitive_Closure.ntrancl": bounded transitive closure on
   322 relations.
   323 
   324 * Constant "Set.not_member" now qualified.  INCOMPATIBILITY.
   325 
   326 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
   327 
   328 * Theory Int: Discontinued many legacy theorems specific to type int.
   329 INCOMPATIBILITY, use the corresponding generic theorems instead.
   330 
   331   zminus_zminus ~> minus_minus
   332   zminus_0 ~> minus_zero
   333   zminus_zadd_distrib ~> minus_add_distrib
   334   zadd_commute ~> add_commute
   335   zadd_assoc ~> add_assoc
   336   zadd_left_commute ~> add_left_commute
   337   zadd_ac ~> add_ac
   338   zmult_ac ~> mult_ac
   339   zadd_0 ~> add_0_left
   340   zadd_0_right ~> add_0_right
   341   zadd_zminus_inverse2 ~> left_minus
   342   zmult_zminus ~> mult_minus_left
   343   zmult_commute ~> mult_commute
   344   zmult_assoc ~> mult_assoc
   345   zadd_zmult_distrib ~> left_distrib
   346   zadd_zmult_distrib2 ~> right_distrib
   347   zdiff_zmult_distrib ~> left_diff_distrib
   348   zdiff_zmult_distrib2 ~> right_diff_distrib
   349   zmult_1 ~> mult_1_left
   350   zmult_1_right ~> mult_1_right
   351   zle_refl ~> order_refl
   352   zle_trans ~> order_trans
   353   zle_antisym ~> order_antisym
   354   zle_linear ~> linorder_linear
   355   zless_linear ~> linorder_less_linear
   356   zadd_left_mono ~> add_left_mono
   357   zadd_strict_right_mono ~> add_strict_right_mono
   358   zadd_zless_mono ~> add_less_le_mono
   359   int_0_less_1 ~> zero_less_one
   360   int_0_neq_1 ~> zero_neq_one
   361   zless_le ~> less_le
   362   zpower_zadd_distrib ~> power_add
   363   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   364   zero_le_zpower_abs ~> zero_le_power_abs
   365 
   366 * Theory Deriv: Renamed
   367 
   368   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   369 
   370 * New "case_product" attribute to generate a case rule doing multiple
   371 case distinctions at the same time.  E.g.
   372 
   373   list.exhaust [case_product nat.exhaust]
   374 
   375 produces a rule which can be used to perform case distinction on both
   376 a list and a nat.
   377 
   378 * Improved code generation of multisets.
   379 
   380 * New diagnostic command find_unused_assms to find potentially superfluous
   381   assumptions in theorems using Quickcheck.
   382 
   383 * Quickcheck:
   384   - Quickcheck returns variable assignments as counterexamples, which
   385     allows to reveal the underspecification of functions under test.
   386     For example, refuting "hd xs = x", it presents the variable
   387     assignment xs = [] and x = a1 as a counterexample, assuming that
   388     any property is false whenever "hd []" occurs in it.
   389     These counterexample are marked as potentially spurious, as
   390     Quickcheck also returns "xs = []" as a counterexample to the
   391     obvious theorem "hd xs = hd xs".
   392     After finding a potentially spurious counterexample, Quickcheck
   393     continues searching for genuine ones.
   394     By default, Quickcheck shows potentially spurious and genuine
   395     counterexamples. The option "genuine_only" sets quickcheck to
   396     only show genuine counterexamples.
   397 
   398   - The command 'quickcheck_generator' creates random and exhaustive
   399     value generators for a given type and operations.
   400     It generates values by using the operations as if they were
   401     constructors of that type. 
   402 
   403   - Support for multisets.
   404 
   405   - Added "use_subtype" options.
   406  
   407 * Nitpick:
   408   - Fixed infinite loop caused by the 'peephole_optim' option and
   409     affecting 'rat' and 'real'.
   410 
   411 * Sledgehammer:
   412   - Added "lam_trans", "uncurry_aliases", and "minimize" options.
   413   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   414   - Renamed "sound" option to "strict".
   415 
   416 * Metis:
   417   - Added possibility to specify lambda translations scheme as a
   418     parenthesized argument (e.g., "by (metis (lifting) ...)").
   419 
   420 * Command 'try0':
   421   - Renamed from 'try_methods'. INCOMPATIBILITY.
   422 
   423 * New "eventually_elim" method as a generalized variant of the
   424   eventually_elim* rules. Supports structured proofs.
   425 
   426 
   427 *** FOL ***
   428 
   429 * New "case_product" attribute (see HOL).
   430 
   431 
   432 *** ML ***
   433 
   434 * Antiquotation @{keyword "name"} produces a parser for outer syntax
   435 from a minor keyword introduced via theory header declaration.
   436 
   437 * Antiquotation @{command_spec "name"} produces the
   438 Outer_Syntax.command_spec from a major keyword introduced via theory
   439 header declaration; it can be passed to Outer_Syntax.command etc.
   440 
   441 * Local_Theory.define no longer hard-wires default theorem name
   442 "foo_def", but retains the binding as given.  If that is Binding.empty
   443 / Attrib.empty_binding, the result is not registered as user-level
   444 fact.  The Local_Theory.define_internal variant allows to specify a
   445 non-empty name (used for the foundation in the background theory),
   446 while omitting the fact binding in the user-context.  Potential
   447 INCOMPATIBILITY for derived definitional packages: need to specify
   448 naming policy for primitive definitions more explicitly.
   449 
   450 * Renamed Thm.capply to Thm.apply, and Thm.cabs to Thm.lambda in
   451 conformance with similar operations in structure Term and Logic.
   452 
   453 * Antiquotation @{attributes [...]} embeds attribute source
   454 representation into the ML text, which is particularly useful with
   455 declarations like Local_Theory.note.
   456 
   457 * Structure Proof_Context follows standard naming scheme.  Old
   458 ProofContext has been discontinued.  INCOMPATIBILITY.
   459 
   460 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   461 change of semantics: update is applied to auxiliary local theory
   462 context as well.
   463 
   464 * Modernized some old-style infix operations:
   465 
   466   addeqcongs    ~> Simplifier.add_eqcong
   467   deleqcongs    ~> Simplifier.del_eqcong
   468   addcongs      ~> Simplifier.add_cong
   469   delcongs      ~> Simplifier.del_cong
   470   setmksimps    ~> Simplifier.set_mksimps
   471   setmkcong     ~> Simplifier.set_mkcong
   472   setmksym      ~> Simplifier.set_mksym
   473   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   474   settermless   ~> Simplifier.set_termless
   475   setsubgoaler  ~> Simplifier.set_subgoaler
   476   addsplits     ~> Splitter.add_split
   477   delsplits     ~> Splitter.del_split
   478 
   479 
   480 
   481 New in Isabelle2011-1 (October 2011)
   482 ------------------------------------
   483 
   484 *** General ***
   485 
   486 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   487 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   488 
   489   - Management of multiple theory files directly from the editor
   490     buffer store -- bypassing the file-system (no requirement to save
   491     files for checking).
   492 
   493   - Markup of formal entities within the text buffer, with semantic
   494     highlighting, tooltips and hyperlinks to jump to defining source
   495     positions.
   496 
   497   - Improved text rendering, with sub/superscripts in the source
   498     buffer (including support for copy/paste wrt. output panel, HTML
   499     theory output and other non-Isabelle text boxes).
   500 
   501   - Refined scheduling of proof checking and printing of results,
   502     based on interactive editor view.  (Note: jEdit folding and
   503     narrowing allows to restrict buffer perspectives explicitly.)
   504 
   505   - Reduced CPU performance requirements, usable on machines with few
   506     cores.
   507 
   508   - Reduced memory requirements due to pruning of unused document
   509     versions (garbage collection).
   510 
   511 See also ~~/src/Tools/jEdit/README.html for further information,
   512 including some remaining limitations.
   513 
   514 * Theory loader: source files are exclusively located via the master
   515 directory of each theory node (where the .thy file itself resides).
   516 The global load path (such as src/HOL/Library) has been discontinued.
   517 Note that the path element ~~ may be used to reference theories in the
   518 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   519 INCOMPATIBILITY.
   520 
   521 * Theory loader: source files are identified by content via SHA1
   522 digests.  Discontinued former path/modtime identification and optional
   523 ISABELLE_FILE_IDENT plugin scripts.
   524 
   525 * Parallelization of nested Isar proofs is subject to
   526 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   527 usedir option -Q.
   528 
   529 * Name space: former unsynchronized references are now proper
   530 configuration options, with more conventional names:
   531 
   532   long_names   ~> names_long
   533   short_names  ~> names_short
   534   unique_names ~> names_unique
   535 
   536 Minor INCOMPATIBILITY, need to declare options in context like this:
   537 
   538   declare [[names_unique = false]]
   539 
   540 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   541 that the result needs to be unique, which means fact specifications
   542 may have to be refined after enriching a proof context.
   543 
   544 * Attribute "case_names" has been refined: the assumptions in each case
   545 can be named now by following the case name with [name1 name2 ...].
   546 
   547 * Isabelle/Isar reference manual has been updated and extended:
   548   - "Synopsis" provides a catalog of main Isar language concepts.
   549   - Formal references in syntax diagrams, via @{rail} antiquotation.
   550   - Updated material from classic "ref" manual, notably about
   551     "Classical Reasoner".
   552 
   553 
   554 *** HOL ***
   555 
   556 * Class bot and top require underlying partial order rather than
   557 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   558 
   559 * Class complete_lattice: generalized a couple of lemmas from sets;
   560 generalized theorems INF_cong and SUP_cong.  New type classes for
   561 complete boolean algebras and complete linear orders.  Lemmas
   562 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   563 class complete_linorder.
   564 
   565 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   566 Sup_fun_def, Inf_apply, Sup_apply.
   567 
   568 Removed redundant lemmas (the right hand side gives hints how to
   569 replace them for (metis ...), or (simp only: ...) proofs):
   570 
   571   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   572   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   573   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   574   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   575   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   576   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   577   Inter_def ~> INF_def, image_def
   578   Union_def ~> SUP_def, image_def
   579   INT_eq ~> INF_def, and image_def
   580   UN_eq ~> SUP_def, and image_def
   581   INF_subset ~> INF_superset_mono [OF _ order_refl]
   582 
   583 More consistent and comprehensive names:
   584 
   585   INTER_eq_Inter_image ~> INF_def
   586   UNION_eq_Union_image ~> SUP_def
   587   INFI_def ~> INF_def
   588   SUPR_def ~> SUP_def
   589   INF_leI ~> INF_lower
   590   INF_leI2 ~> INF_lower2
   591   le_INFI ~> INF_greatest
   592   le_SUPI ~> SUP_upper
   593   le_SUPI2 ~> SUP_upper2
   594   SUP_leI ~> SUP_least
   595   INFI_bool_eq ~> INF_bool_eq
   596   SUPR_bool_eq ~> SUP_bool_eq
   597   INFI_apply ~> INF_apply
   598   SUPR_apply ~> SUP_apply
   599   INTER_def ~> INTER_eq
   600   UNION_def ~> UNION_eq
   601 
   602 INCOMPATIBILITY.
   603 
   604 * Renamed theory Complete_Lattice to Complete_Lattices.
   605 INCOMPATIBILITY.
   606 
   607 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   608 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   609 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   610 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   611 
   612 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   613 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   614 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   615 INCOMPATIBILITY.
   616 
   617 * Added syntactic classes "inf" and "sup" for the respective
   618 constants.  INCOMPATIBILITY: Changes in the argument order of the
   619 (mostly internal) locale predicates for some derived classes.
   620 
   621 * Theorem collections ball_simps and bex_simps do not contain theorems
   622 referring to UNION any longer; these have been moved to collection
   623 UN_ball_bex_simps.  INCOMPATIBILITY.
   624 
   625 * Theory Archimedean_Field: floor now is defined as parameter of a
   626 separate type class floor_ceiling.
   627 
   628 * Theory Finite_Set: more coherent development of fold_set locales:
   629 
   630     locale fun_left_comm ~> locale comp_fun_commute
   631     locale fun_left_comm_idem ~> locale comp_fun_idem
   632 
   633 Both use point-free characterization; interpretation proofs may need
   634 adjustment.  INCOMPATIBILITY.
   635 
   636 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   637 accordance with standard mathematical terminology. INCOMPATIBILITY.
   638 
   639 * Theory Complex_Main: The locale interpretations for the
   640 bounded_linear and bounded_bilinear locales have been removed, in
   641 order to reduce the number of duplicate lemmas. Users must use the
   642 original names for distributivity theorems, potential INCOMPATIBILITY.
   643 
   644   divide.add ~> add_divide_distrib
   645   divide.diff ~> diff_divide_distrib
   646   divide.setsum ~> setsum_divide_distrib
   647   mult.add_right ~> right_distrib
   648   mult.diff_right ~> right_diff_distrib
   649   mult_right.setsum ~> setsum_right_distrib
   650   mult_left.diff ~> left_diff_distrib
   651 
   652 * Theory Complex_Main: Several redundant theorems have been removed or
   653 replaced by more general versions. INCOMPATIBILITY.
   654 
   655   real_diff_def ~> minus_real_def
   656   real_divide_def ~> divide_real_def
   657   real_less_def ~> less_le
   658   real_abs_def ~> abs_real_def
   659   real_sgn_def ~> sgn_real_def
   660   real_mult_commute ~> mult_commute
   661   real_mult_assoc ~> mult_assoc
   662   real_mult_1 ~> mult_1_left
   663   real_add_mult_distrib ~> left_distrib
   664   real_zero_not_eq_one ~> zero_neq_one
   665   real_mult_inverse_left ~> left_inverse
   666   INVERSE_ZERO ~> inverse_zero
   667   real_le_refl ~> order_refl
   668   real_le_antisym ~> order_antisym
   669   real_le_trans ~> order_trans
   670   real_le_linear ~> linear
   671   real_le_eq_diff ~> le_iff_diff_le_0
   672   real_add_left_mono ~> add_left_mono
   673   real_mult_order ~> mult_pos_pos
   674   real_mult_less_mono2 ~> mult_strict_left_mono
   675   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   676   real_0_le_divide_iff ~> zero_le_divide_iff
   677   realpow_two_disj ~> power2_eq_iff
   678   real_squared_diff_one_factored ~> square_diff_one_factored
   679   realpow_two_diff ~> square_diff_square_factored
   680   reals_complete2 ~> complete_real
   681   real_sum_squared_expand ~> power2_sum
   682   exp_ln_eq ~> ln_unique
   683   expi_add ~> exp_add
   684   expi_zero ~> exp_zero
   685   lemma_DERIV_subst ~> DERIV_cong
   686   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   687   LIMSEQ_const ~> tendsto_const
   688   LIMSEQ_norm ~> tendsto_norm
   689   LIMSEQ_add ~> tendsto_add
   690   LIMSEQ_minus ~> tendsto_minus
   691   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   692   LIMSEQ_diff ~> tendsto_diff
   693   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   694   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   695   LIMSEQ_mult ~> tendsto_mult
   696   LIMSEQ_inverse ~> tendsto_inverse
   697   LIMSEQ_divide ~> tendsto_divide
   698   LIMSEQ_pow ~> tendsto_power
   699   LIMSEQ_setsum ~> tendsto_setsum
   700   LIMSEQ_setprod ~> tendsto_setprod
   701   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   702   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   703   LIMSEQ_imp_rabs ~> tendsto_rabs
   704   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   705   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   706   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   707   LIMSEQ_Complex ~> tendsto_Complex
   708   LIM_ident ~> tendsto_ident_at
   709   LIM_const ~> tendsto_const
   710   LIM_add ~> tendsto_add
   711   LIM_add_zero ~> tendsto_add_zero
   712   LIM_minus ~> tendsto_minus
   713   LIM_diff ~> tendsto_diff
   714   LIM_norm ~> tendsto_norm
   715   LIM_norm_zero ~> tendsto_norm_zero
   716   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   717   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   718   LIM_rabs ~> tendsto_rabs
   719   LIM_rabs_zero ~> tendsto_rabs_zero
   720   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   721   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   722   LIM_compose ~> tendsto_compose
   723   LIM_mult ~> tendsto_mult
   724   LIM_scaleR ~> tendsto_scaleR
   725   LIM_of_real ~> tendsto_of_real
   726   LIM_power ~> tendsto_power
   727   LIM_inverse ~> tendsto_inverse
   728   LIM_sgn ~> tendsto_sgn
   729   isCont_LIM_compose ~> isCont_tendsto_compose
   730   bounded_linear.LIM ~> bounded_linear.tendsto
   731   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   732   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   733   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   734   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   735   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   736   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   737 
   738 * Theory Complex_Main: The definition of infinite series was
   739 generalized.  Now it is defined on the type class {topological_space,
   740 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   741 
   742 * Theory Complex_Main: The complex exponential function "expi" is now
   743 a type-constrained abbreviation for "exp :: complex => complex"; thus
   744 several polymorphic lemmas about "exp" are now applicable to "expi".
   745 
   746 * Code generation:
   747 
   748   - Theory Library/Code_Char_ord provides native ordering of
   749     characters in the target language.
   750 
   751   - Commands code_module and code_library are legacy, use export_code
   752     instead.
   753 
   754   - Method "evaluation" is legacy, use method "eval" instead.
   755 
   756   - Legacy evaluator "SML" is deactivated by default.  May be
   757     reactivated by the following theory command:
   758 
   759       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   760 
   761 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   762 
   763 * New proof method "induction" that gives induction hypotheses the
   764 name "IH", thus distinguishing them from further hypotheses that come
   765 from rule induction.  The latter are still called "hyps".  Method
   766 "induction" is a thin wrapper around "induct" and follows the same
   767 syntax.
   768 
   769 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
   770 still available as a legacy feature for some time.
   771 
   772 * Nitpick:
   773   - Added "need" and "total_consts" options.
   774   - Reintroduced "show_skolems" option by popular demand.
   775   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   776     INCOMPATIBILITY.
   777 
   778 * Sledgehammer:
   779   - Use quasi-sound (and efficient) translations by default.
   780   - Added support for the following provers: E-ToFoF, LEO-II,
   781     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
   782   - Automatically preplay and minimize proofs before showing them if
   783     this can be done within reasonable time.
   784   - sledgehammer available_provers ~> sledgehammer supported_provers.
   785     INCOMPATIBILITY.
   786   - Added "preplay_timeout", "slicing", "type_enc", "sound",
   787     "max_mono_iters", and "max_new_mono_instances" options.
   788   - Removed "explicit_apply" and "full_types" options as well as "Full
   789     Types" Proof General menu item. INCOMPATIBILITY.
   790 
   791 * Metis:
   792   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   793   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
   794     INCOMPATIBILITY.
   795 
   796 * Command 'try':
   797   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
   798     "elim:" options. INCOMPATIBILITY.
   799   - Introduced 'try' that not only runs 'try_methods' but also
   800     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
   801 
   802 * Quickcheck:
   803   - Added "eval" option to evaluate terms for the found counterexample
   804     (currently only supported by the default (exhaustive) tester).
   805   - Added post-processing of terms to obtain readable counterexamples
   806     (currently only supported by the default (exhaustive) tester).
   807   - New counterexample generator quickcheck[narrowing] enables
   808     narrowing-based testing.  Requires the Glasgow Haskell compiler
   809     with its installation location defined in the Isabelle settings
   810     environment as ISABELLE_GHC.
   811   - Removed quickcheck tester "SML" based on the SML code generator
   812     (formly in HOL/Library).
   813 
   814 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
   815 use 'partial_function' instead.
   816 
   817 * Theory Library/Extended_Reals replaces now the positive extended
   818 reals found in probability theory. This file is extended by
   819 Multivariate_Analysis/Extended_Real_Limits.
   820 
   821 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
   822 from where it must be imported explicitly if it is really required.
   823 INCOMPATIBILITY.
   824 
   825 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
   826 been moved here.  INCOMPATIBILITY.
   827 
   828 * Theory Library/Saturated provides type of numbers with saturated
   829 arithmetic.
   830 
   831 * Theory Library/Product_Lattice defines a pointwise ordering for the
   832 product type 'a * 'b, and provides instance proofs for various order
   833 and lattice type classes.
   834 
   835 * Theory Library/Countable now provides the "countable_datatype" proof
   836 method for proving "countable" class instances for datatypes.
   837 
   838 * Theory Library/Cset_Monad allows do notation for computable sets
   839 (cset) via the generic monad ad-hoc overloading facility.
   840 
   841 * Library: Theories of common data structures are split into theories
   842 for implementation, an invariant-ensuring type, and connection to an
   843 abstract type. INCOMPATIBILITY.
   844 
   845   - RBT is split into RBT and RBT_Mapping.
   846   - AssocList is split and renamed into AList and AList_Mapping.
   847   - DList is split into DList_Impl, DList, and DList_Cset.
   848   - Cset is split into Cset and List_Cset.
   849 
   850 * Theory Library/Nat_Infinity has been renamed to
   851 Library/Extended_Nat, with name changes of the following types and
   852 constants:
   853 
   854   type inat   ~> type enat
   855   Fin         ~> enat
   856   Infty       ~> infinity (overloaded)
   857   iSuc        ~> eSuc
   858   the_Fin     ~> the_enat
   859 
   860 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   861 been renamed accordingly. INCOMPATIBILITY.
   862 
   863 * Session Multivariate_Analysis: The euclidean_space type class now
   864 fixes a constant "Basis :: 'a set" consisting of the standard
   865 orthonormal basis for the type. Users now have the option of
   866 quantifying over this set instead of using the "basis" function, e.g.
   867 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
   868 
   869 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   870 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   871 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   872 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   873 changed to match. Definition theorems for overloaded constants now use
   874 the standard "foo_vec_def" naming scheme. A few other theorems have
   875 been renamed as follows (INCOMPATIBILITY):
   876 
   877   Cart_eq          ~> vec_eq_iff
   878   dist_nth_le_cart ~> dist_vec_nth_le
   879   tendsto_vector   ~> vec_tendstoI
   880   Cauchy_vector    ~> vec_CauchyI
   881 
   882 * Session Multivariate_Analysis: Several duplicate theorems have been
   883 removed, and other theorems have been renamed or replaced with more
   884 general versions. INCOMPATIBILITY.
   885 
   886   finite_choice ~> finite_set_choice
   887   eventually_conjI ~> eventually_conj
   888   eventually_and ~> eventually_conj_iff
   889   eventually_false ~> eventually_False
   890   setsum_norm ~> norm_setsum
   891   Lim_sequentially ~> LIMSEQ_def
   892   Lim_ident_at ~> LIM_ident
   893   Lim_const ~> tendsto_const
   894   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   895   Lim_neg ~> tendsto_minus
   896   Lim_add ~> tendsto_add
   897   Lim_sub ~> tendsto_diff
   898   Lim_mul ~> tendsto_scaleR
   899   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   900   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   901   Lim_linear ~> bounded_linear.tendsto
   902   Lim_component ~> tendsto_euclidean_component
   903   Lim_component_cart ~> tendsto_vec_nth
   904   Lim_inner ~> tendsto_inner [OF tendsto_const]
   905   dot_lsum ~> inner_setsum_left
   906   dot_rsum ~> inner_setsum_right
   907   continuous_cmul ~> continuous_scaleR [OF continuous_const]
   908   continuous_neg ~> continuous_minus
   909   continuous_sub ~> continuous_diff
   910   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
   911   continuous_mul ~> continuous_scaleR
   912   continuous_inv ~> continuous_inverse
   913   continuous_at_within_inv ~> continuous_at_within_inverse
   914   continuous_at_inv ~> continuous_at_inverse
   915   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
   916   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
   917   continuous_at_component ~> continuous_component [OF continuous_at_id]
   918   continuous_on_neg ~> continuous_on_minus
   919   continuous_on_sub ~> continuous_on_diff
   920   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   921   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   922   continuous_on_mul ~> continuous_on_scaleR
   923   continuous_on_mul_real ~> continuous_on_mult
   924   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   925   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
   926   continuous_on_inverse ~> continuous_on_inv
   927   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
   928   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
   929   subset_interior ~> interior_mono
   930   subset_closure ~> closure_mono
   931   closure_univ ~> closure_UNIV
   932   real_arch_lt ~> reals_Archimedean2
   933   real_arch ~> reals_Archimedean3
   934   real_abs_norm ~> abs_norm_cancel
   935   real_abs_sub_norm ~> norm_triangle_ineq3
   936   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
   937 
   938 * Session HOL-Probability:
   939   - Caratheodory's extension lemma is now proved for ring_of_sets.
   940   - Infinite products of probability measures are now available.
   941   - Sigma closure is independent, if the generator is independent
   942   - Use extended reals instead of positive extended
   943     reals. INCOMPATIBILITY.
   944 
   945 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
   946 
   947   expand_fun_below ~> fun_below_iff
   948   below_fun_ext ~> fun_belowI
   949   expand_cfun_eq ~> cfun_eq_iff
   950   ext_cfun ~> cfun_eqI
   951   expand_cfun_below ~> cfun_below_iff
   952   below_cfun_ext ~> cfun_belowI
   953   monofun_fun_fun ~> fun_belowD
   954   monofun_fun_arg ~> monofunE
   955   monofun_lub_fun ~> adm_monofun [THEN admD]
   956   cont_lub_fun ~> adm_cont [THEN admD]
   957   cont2cont_Rep_CFun ~> cont2cont_APP
   958   cont_Rep_CFun_app ~> cont_APP_app
   959   cont_Rep_CFun_app_app ~> cont_APP_app_app
   960   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
   961   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
   962   contlub_cfun ~> lub_APP [symmetric]
   963   contlub_LAM ~> lub_LAM [symmetric]
   964   thelubI ~> lub_eqI
   965   UU_I ~> bottomI
   966   lift_distinct1 ~> lift.distinct(1)
   967   lift_distinct2 ~> lift.distinct(2)
   968   Def_not_UU ~> lift.distinct(2)
   969   Def_inject ~> lift.inject
   970   below_UU_iff ~> below_bottom_iff
   971   eq_UU_iff ~> eq_bottom_iff
   972 
   973 
   974 *** Document preparation ***
   975 
   976 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   977 isar-ref manual, both for description and actual application of the
   978 same.
   979 
   980 * Antiquotation @{value} evaluates the given term and presents its
   981 result.
   982 
   983 * Antiquotations: term style "isub" provides ad-hoc conversion of
   984 variables x1, y23 into subscripted form x\<^isub>1,
   985 y\<^isub>2\<^isub>3.
   986 
   987 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   988 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   989 
   990 * Localized \isabellestyle switch can be used within blocks or groups
   991 like this:
   992 
   993   \isabellestyle{it}  %preferred default
   994   {\isabellestylett @{text "typewriter stuff"}}
   995 
   996 * Discontinued special treatment of hard tabulators.  Implicit
   997 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
   998 layouts.
   999 
  1000 
  1001 *** ML ***
  1002 
  1003 * The inner syntax of sort/type/term/prop supports inlined YXML
  1004 representations within quoted string tokens.  By encoding logical
  1005 entities via Term_XML (in ML or Scala) concrete syntax can be
  1006 bypassed, which is particularly useful for producing bits of text
  1007 under external program control.
  1008 
  1009 * Antiquotations for ML and document preparation are managed as theory
  1010 data, which requires explicit setup.
  1011 
  1012 * Isabelle_Process.is_active allows tools to check if the official
  1013 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
  1014 (better known as Proof General).
  1015 
  1016 * Structure Proof_Context follows standard naming scheme.  Old
  1017 ProofContext is still available for some time as legacy alias.
  1018 
  1019 * Structure Timing provides various operations for timing; supersedes
  1020 former start_timing/end_timing etc.
  1021 
  1022 * Path.print is the official way to show file-system paths to users
  1023 (including quotes etc.).
  1024 
  1025 * Inner syntax: identifiers in parse trees of generic categories
  1026 "logic", "aprop", "idt" etc. carry position information (disguised as
  1027 type constraints).  Occasional INCOMPATIBILITY with non-compliant
  1028 translations that choke on unexpected type constraints.  Positions can
  1029 be stripped in ML translations via Syntax.strip_positions /
  1030 Syntax.strip_positions_ast, or via the syntax constant
  1031 "_strip_positions" within parse trees.  As last resort, positions can
  1032 be disabled via the configuration option Syntax.positions, which is
  1033 called "syntax_positions" in Isar attribute syntax.
  1034 
  1035 * Discontinued special status of various ML structures that contribute
  1036 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
  1037 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
  1038 refer directly to Ast.Constant, Lexicon.is_identifier,
  1039 Syntax_Trans.mk_binder_tr etc.
  1040 
  1041 * Typed print translation: discontinued show_sorts argument, which is
  1042 already available via context of "advanced" translation.
  1043 
  1044 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
  1045 goal states; body tactic needs to address all subgoals uniformly.
  1046 
  1047 * Slightly more special eq_list/eq_set, with shortcut involving
  1048 pointer equality (assumes that eq relation is reflexive).
  1049 
  1050 * Classical tactics use proper Proof.context instead of historic types
  1051 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
  1052 operate directly on Proof.context.  Raw type claset retains its use as
  1053 snapshot of the classical context, which can be recovered via
  1054 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
  1055 INCOMPATIBILITY, classical tactics and derived proof methods require
  1056 proper Proof.context.
  1057 
  1058 
  1059 *** System ***
  1060 
  1061 * Discontinued support for Poly/ML 5.2, which was the last version
  1062 without proper multithreading and TimeLimit implementation.
  1063 
  1064 * Discontinued old lib/scripts/polyml-platform, which has been
  1065 obsolete since Isabelle2009-2.
  1066 
  1067 * Various optional external tools are referenced more robustly and
  1068 uniformly by explicit Isabelle settings as follows:
  1069 
  1070   ISABELLE_CSDP   (formerly CSDP_EXE)
  1071   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
  1072   ISABELLE_OCAML  (formerly EXEC_OCAML)
  1073   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
  1074   ISABELLE_YAP    (formerly EXEC_YAP)
  1075 
  1076 Note that automated detection from the file-system or search path has
  1077 been discontinued.  INCOMPATIBILITY.
  1078 
  1079 * Scala layer provides JVM method invocation service for static
  1080 methods of type (String)String, see Invoke_Scala.method in ML.  For
  1081 example:
  1082 
  1083   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
  1084 
  1085 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
  1086 this allows to pass structured values between ML and Scala.
  1087 
  1088 * The IsabelleText fonts includes some further glyphs to support the
  1089 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
  1090 installed a local copy (which is normally *not* required) need to
  1091 delete or update it from ~~/lib/fonts/.
  1092 
  1093 
  1094 
  1095 New in Isabelle2011 (January 2011)
  1096 ----------------------------------
  1097 
  1098 *** General ***
  1099 
  1100 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
  1101 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
  1102 useful tooltips and hyperlinks produced from its static analysis.  The
  1103 bundled component provides an executable Isabelle tool that can be run
  1104 like this:
  1105 
  1106   Isabelle2011/bin/isabelle jedit
  1107 
  1108 * Significantly improved Isabelle/Isar implementation manual.
  1109 
  1110 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
  1111 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
  1112 while the default heap location within that directory lacks that extra
  1113 suffix.  This isolates multiple Isabelle installations from each
  1114 other, avoiding problems with old settings in new versions.
  1115 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
  1116 
  1117 * Source files are always encoded as UTF-8, instead of old-fashioned
  1118 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
  1119 the following package declarations:
  1120 
  1121   \usepackage[utf8]{inputenc}
  1122   \usepackage{textcomp}
  1123 
  1124 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
  1125 a Unicode character is treated as a single symbol, not a sequence of
  1126 non-ASCII bytes as before.  Since Isabelle/ML string literals may
  1127 contain symbols without further backslash escapes, Unicode can now be
  1128 used here as well.  Recall that Symbol.explode in ML provides a
  1129 consistent view on symbols, while raw explode (or String.explode)
  1130 merely give a byte-oriented representation.
  1131 
  1132 * Theory loader: source files are primarily located via the master
  1133 directory of each theory node (where the .thy file itself resides).
  1134 The global load path is still partially available as legacy feature.
  1135 Minor INCOMPATIBILITY due to subtle change in file lookup: use
  1136 explicit paths, relatively to the theory.
  1137 
  1138 * Special treatment of ML file names has been discontinued.
  1139 Historically, optional extensions .ML or .sml were added on demand --
  1140 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
  1141 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
  1142 
  1143 * Various options that affect pretty printing etc. are now properly
  1144 handled within the context via configuration options, instead of
  1145 unsynchronized references or print modes.  There are both ML Config.T
  1146 entities and Isar declaration attributes to access these.
  1147 
  1148   ML (Config.T)                 Isar (attribute)
  1149 
  1150   eta_contract                  eta_contract
  1151   show_brackets                 show_brackets
  1152   show_sorts                    show_sorts
  1153   show_types                    show_types
  1154   show_question_marks           show_question_marks
  1155   show_consts                   show_consts
  1156   show_abbrevs                  show_abbrevs
  1157 
  1158   Syntax.ast_trace              syntax_ast_trace
  1159   Syntax.ast_stat               syntax_ast_stat
  1160   Syntax.ambiguity_level        syntax_ambiguity_level
  1161 
  1162   Goal_Display.goals_limit      goals_limit
  1163   Goal_Display.show_main_goal   show_main_goal
  1164 
  1165   Method.rule_trace             rule_trace
  1166 
  1167   Thy_Output.display            thy_output_display
  1168   Thy_Output.quotes             thy_output_quotes
  1169   Thy_Output.indent             thy_output_indent
  1170   Thy_Output.source             thy_output_source
  1171   Thy_Output.break              thy_output_break
  1172 
  1173 Note that corresponding "..._default" references in ML may only be
  1174 changed globally at the ROOT session setup, but *not* within a theory.
  1175 The option "show_abbrevs" supersedes the former print mode
  1176 "no_abbrevs" with inverted meaning.
  1177 
  1178 * More systematic naming of some configuration options.
  1179 INCOMPATIBILITY.
  1180 
  1181   trace_simp  ~>  simp_trace
  1182   debug_simp  ~>  simp_debug
  1183 
  1184 * Support for real valued configuration options, using simplistic
  1185 floating-point notation that coincides with the inner syntax for
  1186 float_token.
  1187 
  1188 * Support for real valued preferences (with approximative PGIP type):
  1189 front-ends need to accept "pgint" values in float notation.
  1190 INCOMPATIBILITY.
  1191 
  1192 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
  1193 DejaVu Sans.
  1194 
  1195 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
  1196 
  1197 
  1198 *** Pure ***
  1199 
  1200 * Command 'type_synonym' (with single argument) replaces somewhat
  1201 outdated 'types', which is still available as legacy feature for some
  1202 time.
  1203 
  1204 * Command 'nonterminal' (with 'and' separated list of arguments)
  1205 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
  1206 
  1207 * Command 'notepad' replaces former 'example_proof' for
  1208 experimentation in Isar without any result.  INCOMPATIBILITY.
  1209 
  1210 * Locale interpretation commands 'interpret' and 'sublocale' accept
  1211 lists of equations to map definitions in a locale to appropriate
  1212 entities in the context of the interpretation.  The 'interpretation'
  1213 command already provided this functionality.
  1214 
  1215 * Diagnostic command 'print_dependencies' prints the locale instances
  1216 that would be activated if the specified expression was interpreted in
  1217 the current context.  Variant "print_dependencies!" assumes a context
  1218 without interpretations.
  1219 
  1220 * Diagnostic command 'print_interps' prints interpretations in proofs
  1221 in addition to interpretations in theories.
  1222 
  1223 * Discontinued obsolete 'global' and 'local' commands to manipulate
  1224 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
  1225 Sign.root_path and Sign.local_path may be applied directly where this
  1226 feature is still required for historical reasons.
  1227 
  1228 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
  1229 'definition' instead.
  1230 
  1231 * The "prems" fact, which refers to the accidental collection of
  1232 foundational premises in the context, is now explicitly marked as
  1233 legacy feature and will be discontinued soon.  Consider using "assms"
  1234 of the head statement or reference facts by explicit names.
  1235 
  1236 * Document antiquotations @{class} and @{type} print classes and type
  1237 constructors.
  1238 
  1239 * Document antiquotation @{file} checks file/directory entries within
  1240 the local file system.
  1241 
  1242 
  1243 *** HOL ***
  1244 
  1245 * Coercive subtyping: functions can be declared as coercions and type
  1246 inference will add them as necessary upon input of a term.  Theory
  1247 Complex_Main declares real :: nat => real and real :: int => real as
  1248 coercions. A coercion function f is declared like this:
  1249 
  1250   declare [[coercion f]]
  1251 
  1252 To lift coercions through type constructors (e.g. from nat => real to
  1253 nat list => real list), map functions can be declared, e.g.
  1254 
  1255   declare [[coercion_map map]]
  1256 
  1257 Currently coercion inference is activated only in theories including
  1258 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1259 the configuration option "coercion_enabled", e.g. it can be enabled in
  1260 other theories like this:
  1261 
  1262   declare [[coercion_enabled]]
  1263 
  1264 * Command 'partial_function' provides basic support for recursive
  1265 function definitions over complete partial orders.  Concrete instances
  1266 are provided for i) the option type, ii) tail recursion on arbitrary
  1267 types, and iii) the heap monad of Imperative_HOL.  See
  1268 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1269 for examples.
  1270 
  1271 * Function package: f.psimps rules are no longer implicitly declared
  1272 as [simp].  INCOMPATIBILITY.
  1273 
  1274 * Datatype package: theorems generated for executable equality (class
  1275 "eq") carry proper names and are treated as default code equations.
  1276 
  1277 * Inductive package: now offers command 'inductive_simps' to
  1278 automatically derive instantiated and simplified equations for
  1279 inductive predicates, similar to 'inductive_cases'.
  1280 
  1281 * Command 'enriched_type' allows to register properties of the
  1282 functorial structure of types.
  1283 
  1284 * Improved infrastructure for term evaluation using code generator
  1285 techniques, in particular static evaluation conversions.
  1286 
  1287 * Code generator: Scala (2.8 or higher) has been added to the target
  1288 languages.
  1289 
  1290 * Code generator: globbing constant expressions "*" and "Theory.*"
  1291 have been replaced by the more idiomatic "_" and "Theory._".
  1292 INCOMPATIBILITY.
  1293 
  1294 * Code generator: export_code without explicit file declaration prints
  1295 to standard output.  INCOMPATIBILITY.
  1296 
  1297 * Code generator: do not print function definitions for case
  1298 combinators any longer.
  1299 
  1300 * Code generator: simplification with rules determined with
  1301 src/Tools/Code/code_simp.ML and method "code_simp".
  1302 
  1303 * Code generator for records: more idiomatic representation of record
  1304 types.  Warning: records are not covered by ancient SML code
  1305 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1306 rep_datatype declaration helps to succeed then:
  1307 
  1308   record 'a foo = ...
  1309   ...
  1310   rep_datatype foo_ext ...
  1311 
  1312 * Records: logical foundation type for records does not carry a
  1313 '_type' suffix any longer (obsolete due to authentic syntax).
  1314 INCOMPATIBILITY.
  1315 
  1316 * Quickcheck now by default uses exhaustive testing instead of random
  1317 testing.  Random testing can be invoked by "quickcheck [random]",
  1318 exhaustive testing by "quickcheck [exhaustive]".
  1319 
  1320 * Quickcheck instantiates polymorphic types with small finite
  1321 datatypes by default. This enables a simple execution mechanism to
  1322 handle quantifiers and function equality over the finite datatypes.
  1323 
  1324 * Quickcheck random generator has been renamed from "code" to
  1325 "random".  INCOMPATIBILITY.
  1326 
  1327 * Quickcheck now has a configurable time limit which is set to 30
  1328 seconds by default. This can be changed by adding [timeout = n] to the
  1329 quickcheck command. The time limit for Auto Quickcheck is still set
  1330 independently.
  1331 
  1332 * Quickcheck in locales considers interpretations of that locale for
  1333 counter example search.
  1334 
  1335 * Sledgehammer:
  1336   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1337     method. See the Sledgehammer manual for details ("isabelle doc
  1338     sledgehammer").
  1339   - Renamed commands:
  1340     sledgehammer atp_info ~> sledgehammer running_provers
  1341     sledgehammer atp_kill ~> sledgehammer kill_provers
  1342     sledgehammer available_atps ~> sledgehammer available_provers
  1343     INCOMPATIBILITY.
  1344   - Renamed options:
  1345     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1346     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1347     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1348     (and "ms" and "min" are no longer supported)
  1349     INCOMPATIBILITY.
  1350 
  1351 * Nitpick:
  1352   - Renamed options:
  1353     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1354     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1355     INCOMPATIBILITY.
  1356   - Added support for partial quotient types.
  1357   - Added local versions of the "Nitpick.register_xxx" functions.
  1358   - Added "whack" option.
  1359   - Allow registration of quotient types as codatatypes.
  1360   - Improved "merge_type_vars" option to merge more types.
  1361   - Removed unsound "fast_descrs" option.
  1362   - Added custom symmetry breaking for datatypes, making it possible to reach
  1363     higher cardinalities.
  1364   - Prevent the expansion of too large definitions.
  1365 
  1366 * Proof methods "metis" and "meson" now have configuration options
  1367 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1368 to diagnose these tools. E.g.
  1369 
  1370     using [[metis_trace = true]]
  1371 
  1372 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1373 manually as command 'solve_direct'.
  1374 
  1375 * The default SMT solver Z3 must be enabled explicitly (due to
  1376 licensing issues) by setting the environment variable
  1377 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1378 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1379 changing the SMT solver is done via the configuration option
  1380 "smt_solver".
  1381 
  1382 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1383 i.e. "remote_cvc3" and "remote_z3".
  1384 
  1385 * Added basic SMT support for datatypes, records, and typedefs using
  1386 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1387 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1388 support for a similar behavior).  Minor INCOMPATIBILITY.
  1389 
  1390 * Changed SMT configuration options:
  1391   - Renamed:
  1392     z3_proofs ~> smt_oracle (with inverted meaning)
  1393     z3_trace_assms ~> smt_trace_used_facts
  1394     INCOMPATIBILITY.
  1395   - Added:
  1396     smt_verbose
  1397     smt_random_seed
  1398     smt_datatypes
  1399     smt_infer_triggers
  1400     smt_monomorph_limit
  1401     cvc3_options
  1402     remote_cvc3_options
  1403     remote_z3_options
  1404     yices_options
  1405 
  1406 * Boogie output files (.b2i files) need to be declared in the theory
  1407 header.
  1408 
  1409 * Simplification procedure "list_to_set_comprehension" rewrites list
  1410 comprehensions applied to List.set to set comprehensions.  Occasional
  1411 INCOMPATIBILITY, may be deactivated like this:
  1412 
  1413   declare [[simproc del: list_to_set_comprehension]]
  1414 
  1415 * Removed old version of primrec package.  INCOMPATIBILITY.
  1416 
  1417 * Removed simplifier congruence rule of "prod_case", as has for long
  1418 been the case with "split".  INCOMPATIBILITY.
  1419 
  1420 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1421 
  1422 * Removed [split_format ... and ... and ...] version of
  1423 [split_format].  Potential INCOMPATIBILITY.
  1424 
  1425 * Predicate "sorted" now defined inductively, with nice induction
  1426 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1427 
  1428 * Constant "contents" renamed to "the_elem", to free the generic name
  1429 contents for other uses.  INCOMPATIBILITY.
  1430 
  1431 * Renamed class eq and constant eq (for code generation) to class
  1432 equal and constant equal, plus renaming of related facts and various
  1433 tuning.  INCOMPATIBILITY.
  1434 
  1435 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1436 
  1437 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1438 INCOMPATIBILITY.
  1439 
  1440 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1441 avoid confusion with finite sets.  INCOMPATIBILITY.
  1442 
  1443 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1444 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1445 for congruent(2)).
  1446 
  1447 * Some previously unqualified names have been qualified:
  1448 
  1449   types
  1450     bool ~> HOL.bool
  1451     nat ~> Nat.nat
  1452 
  1453   constants
  1454     Trueprop ~> HOL.Trueprop
  1455     True ~> HOL.True
  1456     False ~> HOL.False
  1457     op & ~> HOL.conj
  1458     op | ~> HOL.disj
  1459     op --> ~> HOL.implies
  1460     op = ~> HOL.eq
  1461     Not ~> HOL.Not
  1462     The ~> HOL.The
  1463     All ~> HOL.All
  1464     Ex ~> HOL.Ex
  1465     Ex1 ~> HOL.Ex1
  1466     Let ~> HOL.Let
  1467     If ~> HOL.If
  1468     Ball ~> Set.Ball
  1469     Bex ~> Set.Bex
  1470     Suc ~> Nat.Suc
  1471     Pair ~> Product_Type.Pair
  1472     fst ~> Product_Type.fst
  1473     snd ~> Product_Type.snd
  1474     curry ~> Product_Type.curry
  1475     op : ~> Set.member
  1476     Collect ~> Set.Collect
  1477 
  1478 INCOMPATIBILITY.
  1479 
  1480 * More canonical naming convention for some fundamental definitions:
  1481 
  1482     bot_bool_eq ~> bot_bool_def
  1483     top_bool_eq ~> top_bool_def
  1484     inf_bool_eq ~> inf_bool_def
  1485     sup_bool_eq ~> sup_bool_def
  1486     bot_fun_eq  ~> bot_fun_def
  1487     top_fun_eq  ~> top_fun_def
  1488     inf_fun_eq  ~> inf_fun_def
  1489     sup_fun_eq  ~> sup_fun_def
  1490 
  1491 INCOMPATIBILITY.
  1492 
  1493 * More stylized fact names:
  1494 
  1495   expand_fun_eq ~> fun_eq_iff
  1496   expand_set_eq ~> set_eq_iff
  1497   set_ext       ~> set_eqI
  1498   nat_number    ~> eval_nat_numeral
  1499 
  1500 INCOMPATIBILITY.
  1501 
  1502 * Refactoring of code-generation specific operations in theory List:
  1503 
  1504   constants
  1505     null ~> List.null
  1506 
  1507   facts
  1508     mem_iff ~> member_def
  1509     null_empty ~> null_def
  1510 
  1511 INCOMPATIBILITY.  Note that these were not supposed to be used
  1512 regularly unless for striking reasons; their main purpose was code
  1513 generation.
  1514 
  1515 Various operations from the Haskell prelude are used for generating
  1516 Haskell code.
  1517 
  1518 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1519 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1520 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1521 
  1522 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1523 "*" and "+" respectively.  INCOMPATIBILITY.
  1524 
  1525 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1526 "Sum_Type.Plus" instead.
  1527 
  1528 * Constant "split" has been merged with constant "prod_case"; names of
  1529 ML functions, facts etc. involving split have been retained so far,
  1530 though.  INCOMPATIBILITY.
  1531 
  1532 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1533 instead.  INCOMPATIBILITY.
  1534 
  1535 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1536 INCOMPATIBILITY.
  1537 
  1538 * Former theory Library/Enum is now part of the HOL-Main image.
  1539 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1540 referred to by its qualified name.
  1541 
  1542   enum    ~>  Enum.enum
  1543   nlists  ~>  Enum.nlists
  1544   product ~>  Enum.product
  1545 
  1546 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1547 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1548 INCOMPATIBILITY.
  1549 
  1550 * Theory Library/SetsAndFunctions has been split into
  1551 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1552 for instance definitions for functions; various improvements.
  1553 INCOMPATIBILITY.
  1554 
  1555 * Theory Library/Multiset provides stable quicksort implementation of
  1556 sort_key.
  1557 
  1558 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1559 INCOMPATIBILITY.
  1560 
  1561 * Session Multivariate_Analysis: introduced a type class for euclidean
  1562 space.  Most theorems are now stated in terms of euclidean spaces
  1563 instead of finite cartesian products.
  1564 
  1565   types
  1566     real ^ 'n ~>  'a::real_vector
  1567               ~>  'a::euclidean_space
  1568               ~>  'a::ordered_euclidean_space
  1569         (depends on your needs)
  1570 
  1571   constants
  1572      _ $ _        ~> _ $$ _
  1573      \<chi> x. _  ~> \<chi>\<chi> x. _
  1574      CARD('n)     ~> DIM('a)
  1575 
  1576 Also note that the indices are now natural numbers and not from some
  1577 finite type. Finite cartesian products of euclidean spaces, products
  1578 of euclidean spaces the real and complex numbers are instantiated to
  1579 be euclidean_spaces.  INCOMPATIBILITY.
  1580 
  1581 * Session Probability: introduced pextreal as positive extended real
  1582 numbers.  Use pextreal as value for measures.  Introduce the
  1583 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1584 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1585 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1586 
  1587 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1588 INCOMPATIBILITY.
  1589 
  1590 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1591 prove verification conditions generated by the SPARK Ada program
  1592 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1593 
  1594 
  1595 *** HOL-Algebra ***
  1596 
  1597 * Theorems for additive ring operations (locale abelian_monoid and
  1598 descendants) are generated by interpretation from their multiplicative
  1599 counterparts.  Names (in particular theorem names) have the mandatory
  1600 qualifier 'add'.  Previous theorem names are redeclared for
  1601 compatibility.
  1602 
  1603 * Structure "int_ring" is now an abbreviation (previously a
  1604 definition).  This fits more natural with advanced interpretations.
  1605 
  1606 
  1607 *** HOLCF ***
  1608 
  1609 * The domain package now runs in definitional mode by default: The
  1610 former command 'new_domain' is now called 'domain'.  To use the domain
  1611 package in its original axiomatic mode, use 'domain (unsafe)'.
  1612 INCOMPATIBILITY.
  1613 
  1614 * The new class "domain" is now the default sort.  Class "predomain"
  1615 is an unpointed version of "domain". Theories can be updated by
  1616 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1617 
  1618   'a::type ~> 'a::countable
  1619   'a::cpo  ~> 'a::predomain
  1620   'a::pcpo ~> 'a::domain
  1621 
  1622 * The old type class "rep" has been superseded by class "domain".
  1623 Accordingly, users of the definitional package must remove any
  1624 "default_sort rep" declarations.  INCOMPATIBILITY.
  1625 
  1626 * The domain package (definitional mode) now supports unpointed
  1627 predomain argument types, as long as they are marked 'lazy'. (Strict
  1628 arguments must be in class "domain".) For example, the following
  1629 domain definition now works:
  1630 
  1631   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1632 
  1633 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1634 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1635 'a option, and 'a list.  Additionally, it configures fixrec and the
  1636 domain package to work with these types.  For example:
  1637 
  1638   fixrec isInl :: "('a + 'b) u -> tr"
  1639     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1640 
  1641   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1642 
  1643 * The "(permissive)" option of fixrec has been replaced with a
  1644 per-equation "(unchecked)" option. See
  1645 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1646 
  1647 * The "bifinite" class no longer fixes a constant "approx"; the class
  1648 now just asserts that such a function exists.  INCOMPATIBILITY.
  1649 
  1650 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1651 defines an embedding of type 'a defl into udom by default; instances
  1652 of "bifinite" and "domain" classes are available in
  1653 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1654 
  1655 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1656 
  1657 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1658 
  1659 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1660 
  1661 * The function "cprod_map" has been renamed to "prod_map".
  1662 INCOMPATIBILITY.
  1663 
  1664 * The monadic bind operator on each powerdomain has new binder syntax
  1665 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1666 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1667 
  1668 * The infix syntax for binary union on each powerdomain has changed
  1669 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1670 syntax.  INCOMPATIBILITY.
  1671 
  1672 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1673 still supported as an input translation.
  1674 
  1675 * Renamed some theorems (the original names are also still available).
  1676 
  1677   expand_fun_below   ~> fun_below_iff
  1678   below_fun_ext      ~> fun_belowI
  1679   expand_cfun_eq     ~> cfun_eq_iff
  1680   ext_cfun           ~> cfun_eqI
  1681   expand_cfun_below  ~> cfun_below_iff
  1682   below_cfun_ext     ~> cfun_belowI
  1683   cont2cont_Rep_CFun ~> cont2cont_APP
  1684 
  1685 * The Abs and Rep functions for various types have changed names.
  1686 Related theorem names have also changed to match. INCOMPATIBILITY.
  1687 
  1688   Rep_CFun  ~> Rep_cfun
  1689   Abs_CFun  ~> Abs_cfun
  1690   Rep_Sprod ~> Rep_sprod
  1691   Abs_Sprod ~> Abs_sprod
  1692   Rep_Ssum  ~> Rep_ssum
  1693   Abs_Ssum  ~> Abs_ssum
  1694 
  1695 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1696 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1697 
  1698 * Various changes to bisimulation/coinduction with domain package:
  1699 
  1700   - Definitions of "bisim" constants no longer mention definedness.
  1701   - With mutual recursion, "bisim" predicate is now curried.
  1702   - With mutual recursion, each type gets a separate coind theorem.
  1703   - Variable names in bisim_def and coinduct rules have changed.
  1704 
  1705 INCOMPATIBILITY.
  1706 
  1707 * Case combinators generated by the domain package for type "foo" are
  1708 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1709 
  1710 * Several theorems have been renamed to more accurately reflect the
  1711 names of constants and types involved.  INCOMPATIBILITY.
  1712 
  1713   thelub_const    ~> lub_const
  1714   lub_const       ~> is_lub_const
  1715   thelubI         ~> lub_eqI
  1716   is_lub_lub      ~> is_lubD2
  1717   lubI            ~> is_lub_lub
  1718   unique_lub      ~> is_lub_unique
  1719   is_ub_lub       ~> is_lub_rangeD1
  1720   lub_bin_chain   ~> is_lub_bin_chain
  1721   lub_fun         ~> is_lub_fun
  1722   thelub_fun      ~> lub_fun
  1723   thelub_cfun     ~> lub_cfun
  1724   thelub_Pair     ~> lub_Pair
  1725   lub_cprod       ~> is_lub_prod
  1726   thelub_cprod    ~> lub_prod
  1727   minimal_cprod   ~> minimal_prod
  1728   inst_cprod_pcpo ~> inst_prod_pcpo
  1729   UU_I            ~> bottomI
  1730   compact_UU      ~> compact_bottom
  1731   deflation_UU    ~> deflation_bottom
  1732   finite_deflation_UU ~> finite_deflation_bottom
  1733 
  1734 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1735 
  1736   sq_ord_less_eq_trans ~> below_eq_trans
  1737   sq_ord_eq_less_trans ~> eq_below_trans
  1738   refl_less            ~> below_refl
  1739   trans_less           ~> below_trans
  1740   antisym_less         ~> below_antisym
  1741   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1742   box_less             ~> box_below
  1743   rev_trans_less       ~> rev_below_trans
  1744   not_less2not_eq      ~> not_below2not_eq
  1745   less_UU_iff          ~> below_UU_iff
  1746   flat_less_iff        ~> flat_below_iff
  1747   adm_less             ~> adm_below
  1748   adm_not_less         ~> adm_not_below
  1749   adm_compact_not_less ~> adm_compact_not_below
  1750   less_fun_def         ~> below_fun_def
  1751   expand_fun_less      ~> fun_below_iff
  1752   less_fun_ext         ~> fun_belowI
  1753   less_discr_def       ~> below_discr_def
  1754   discr_less_eq        ~> discr_below_eq
  1755   less_unit_def        ~> below_unit_def
  1756   less_cprod_def       ~> below_prod_def
  1757   prod_lessI           ~> prod_belowI
  1758   Pair_less_iff        ~> Pair_below_iff
  1759   fst_less_iff         ~> fst_below_iff
  1760   snd_less_iff         ~> snd_below_iff
  1761   expand_cfun_less     ~> cfun_below_iff
  1762   less_cfun_ext        ~> cfun_belowI
  1763   injection_less       ~> injection_below
  1764   less_up_def          ~> below_up_def
  1765   not_Iup_less         ~> not_Iup_below
  1766   Iup_less             ~> Iup_below
  1767   up_less              ~> up_below
  1768   Def_inject_less_eq   ~> Def_below_Def
  1769   Def_less_is_eq       ~> Def_below_iff
  1770   spair_less_iff       ~> spair_below_iff
  1771   less_sprod           ~> below_sprod
  1772   spair_less           ~> spair_below
  1773   sfst_less_iff        ~> sfst_below_iff
  1774   ssnd_less_iff        ~> ssnd_below_iff
  1775   fix_least_less       ~> fix_least_below
  1776   dist_less_one        ~> dist_below_one
  1777   less_ONE             ~> below_ONE
  1778   ONE_less_iff         ~> ONE_below_iff
  1779   less_sinlD           ~> below_sinlD
  1780   less_sinrD           ~> below_sinrD
  1781 
  1782 
  1783 *** FOL and ZF ***
  1784 
  1785 * All constant names are now qualified internally and use proper
  1786 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1787 
  1788 *** ZF ***
  1789 
  1790 * Greater support for structured proofs involving induction or case analysis.
  1791 
  1792 * Much greater use of special symbols.
  1793 
  1794 * Removal of many ML theorem bindings. INCOMPATIBILITY.
  1795 
  1796 *** ML ***
  1797 
  1798 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1799 Fail if the argument is false.  Due to inlining the source position of
  1800 failed assertions is included in the error output.
  1801 
  1802 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1803 text is in practice always evaluated with a stable theory checkpoint.
  1804 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1805 
  1806 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1807 the current context, not any accidental theory loader state as before.
  1808 Potential INCOMPATIBILITY, subtle change in semantics.
  1809 
  1810 * Syntax.pretty_priority (default 0) configures the required priority
  1811 of pretty-printed output and thus affects insertion of parentheses.
  1812 
  1813 * Syntax.default_root (default "any") configures the inner syntax
  1814 category (nonterminal symbol) for parsing of terms.
  1815 
  1816 * Former exception Library.UnequalLengths now coincides with
  1817 ListPair.UnequalLengths.
  1818 
  1819 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1820 main functionality is provided by structure Simplifier.
  1821 
  1822 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1823 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1824 almost all situations.
  1825 
  1826 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1827 See implementation manual for further details on exceptions in
  1828 Isabelle/ML.
  1829 
  1830 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1831 meaning.
  1832 
  1833 * Renamed structure PureThy to Pure_Thy and moved most of its
  1834 operations to structure Global_Theory, to emphasize that this is
  1835 rarely-used global-only stuff.
  1836 
  1837 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1838 instead (or tracing for high-volume output).
  1839 
  1840 * Configuration option show_question_marks only affects regular pretty
  1841 printing of types and terms, not raw Term.string_of_vname.
  1842 
  1843 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1844 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1845 @{thms} for most purposes.
  1846 
  1847 * ML structure Unsynchronized is never opened, not even in Isar
  1848 interaction mode as before.  Old Unsynchronized.set etc. have been
  1849 discontinued -- use plain := instead.  This should be *rare* anyway,
  1850 since modern tools always work via official context data, notably
  1851 configuration options.
  1852 
  1853 * Parallel and asynchronous execution requires special care concerning
  1854 interrupts.  Structure Exn provides some convenience functions that
  1855 avoid working directly with raw Interrupt.  User code must not absorb
  1856 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1857 followed by re-raising of the original exception.  Another common
  1858 source of mistakes are "handle _" patterns, which make the meaning of
  1859 the program subject to physical effects of the environment.
  1860 
  1861 
  1862 
  1863 New in Isabelle2009-2 (June 2010)
  1864 ---------------------------------
  1865 
  1866 *** General ***
  1867 
  1868 * Authentic syntax for *all* logical entities (type classes, type
  1869 constructors, term constants): provides simple and robust
  1870 correspondence between formal entities and concrete syntax.  Within
  1871 the parse tree / AST representations, "constants" are decorated by
  1872 their category (class, type, const) and spelled out explicitly with
  1873 their full internal name.
  1874 
  1875 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1876 and translations (translation rules and translation functions in ML).
  1877 Some hints on upgrading:
  1878 
  1879   - Many existing uses of 'syntax' and 'translations' can be replaced
  1880     by more modern 'type_notation', 'notation' and 'abbreviation',
  1881     which are independent of this issue.
  1882 
  1883   - 'translations' require markup within the AST; the term syntax
  1884     provides the following special forms:
  1885 
  1886       CONST c   -- produces syntax version of constant c from context
  1887       XCONST c  -- literally c, checked as constant from context
  1888       c         -- literally c, if declared by 'syntax'
  1889 
  1890     Plain identifiers are treated as AST variables -- occasionally the
  1891     system indicates accidental variables via the error "rhs contains
  1892     extra variables".
  1893 
  1894     Type classes and type constructors are marked according to their
  1895     concrete syntax.  Some old translations rules need to be written
  1896     for the "type" category, using type constructor application
  1897     instead of pseudo-term application of the default category
  1898     "logic".
  1899 
  1900   - 'parse_translation' etc. in ML may use the following
  1901     antiquotations:
  1902 
  1903       @{class_syntax c}   -- type class c within parse tree / AST
  1904       @{term_syntax c}    -- type constructor c within parse tree / AST
  1905       @{const_syntax c}   -- ML version of "CONST c" above
  1906       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1907 
  1908   - Literal types within 'typed_print_translations', i.e. those *not*
  1909     represented as pseudo-terms are represented verbatim.  Use @{class
  1910     c} or @{type_name c} here instead of the above syntax
  1911     antiquotations.
  1912 
  1913 Note that old non-authentic syntax was based on unqualified base
  1914 names, so all of the above "constant" names would coincide.  Recall
  1915 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1916 diagnose syntax problems.
  1917 
  1918 * Type constructors admit general mixfix syntax, not just infix.
  1919 
  1920 * Concrete syntax may be attached to local entities without a proof
  1921 body, too.  This works via regular mixfix annotations for 'fix',
  1922 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1923 similar to the 'notation' command in theory specifications.
  1924 
  1925 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1926 need to specify constant name and syntax separately.  Internal ML
  1927 datatype constructors have been renamed from InfixName to Infix etc.
  1928 Minor INCOMPATIBILITY.
  1929 
  1930 * Schematic theorem statements need to be explicitly markup as such,
  1931 via commands 'schematic_lemma', 'schematic_theorem',
  1932 'schematic_corollary'.  Thus the relevance of the proof is made
  1933 syntactically clear, which impacts performance in a parallel or
  1934 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1935 
  1936 * Use of cumulative prems via "!" in some proof methods has been
  1937 discontinued (old legacy feature).
  1938 
  1939 * References 'trace_simp' and 'debug_simp' have been replaced by
  1940 configuration options stored in the context. Enabling tracing (the
  1941 case of debugging is similar) in proofs works via
  1942 
  1943   using [[trace_simp = true]]
  1944 
  1945 Tracing is then active for all invocations of the simplifier in
  1946 subsequent goal refinement steps. Tracing may also still be enabled or
  1947 disabled via the ProofGeneral settings menu.
  1948 
  1949 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1950 'hide_fact' replace the former 'hide' KIND command.  Minor
  1951 INCOMPATIBILITY.
  1952 
  1953 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1954 more efficient than combinations with -q1 or -q2.
  1955 
  1956 
  1957 *** Pure ***
  1958 
  1959 * Proofterms record type-class reasoning explicitly, using the
  1960 "unconstrain" operation internally.  This eliminates all sort
  1961 constraints from a theorem and proof, introducing explicit
  1962 OFCLASS-premises.  On the proof term level, this operation is
  1963 automatically applied at theorem boundaries, such that closed proofs
  1964 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1965 inspect proof terms.
  1966 
  1967 * Local theory specifications may depend on extra type variables that
  1968 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1969 are added internally.  For example:
  1970 
  1971   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1972 
  1973 * Predicates of locales introduced by classes carry a mandatory
  1974 "class" prefix.  INCOMPATIBILITY.
  1975 
  1976 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1977 
  1978 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1979 'class' instead.
  1980 
  1981 * Command 'code_reflect' allows to incorporate generated ML code into
  1982 runtime environment; replaces immature code_datatype antiquotation.
  1983 INCOMPATIBILITY.
  1984 
  1985 * Code generator: simple concept for abstract datatypes obeying
  1986 invariants.
  1987 
  1988 * Code generator: details of internal data cache have no impact on the
  1989 user space functionality any longer.
  1990 
  1991 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1992 subgoals.  This is more appropriate for interpretations with 'where'.
  1993 INCOMPATIBILITY.
  1994 
  1995 * Command 'example_proof' opens an empty proof body.  This allows to
  1996 experiment with Isar, without producing any persistent result.
  1997 
  1998 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1999 within a local theory context, with explicit checking of the
  2000 constructors involved (in contrast to the raw 'syntax' versions).
  2001 
  2002 * Commands 'types' and 'typedecl' now work within a local theory
  2003 context -- without introducing dependencies on parameters or
  2004 assumptions, which is not possible in Isabelle/Pure.
  2005 
  2006 * Command 'defaultsort' has been renamed to 'default_sort', it works
  2007 within a local theory context.  Minor INCOMPATIBILITY.
  2008 
  2009 
  2010 *** HOL ***
  2011 
  2012 * Command 'typedef' now works within a local theory context -- without
  2013 introducing dependencies on parameters or assumptions, which is not
  2014 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  2015 contain multiple interpretations of local typedefs (with different
  2016 non-emptiness proofs), even in a global theory context.
  2017 
  2018 * New package for quotient types.  Commands 'quotient_type' and
  2019 'quotient_definition' may be used for defining types and constants by
  2020 quotient constructions.  An example is the type of integers created by
  2021 quotienting pairs of natural numbers:
  2022 
  2023   fun
  2024     intrel :: "(nat * nat) => (nat * nat) => bool"
  2025   where
  2026     "intrel (x, y) (u, v) = (x + v = u + y)"
  2027 
  2028   quotient_type int = "nat * nat" / intrel
  2029     by (auto simp add: equivp_def expand_fun_eq)
  2030 
  2031   quotient_definition
  2032     "0::int" is "(0::nat, 0::nat)"
  2033 
  2034 The method "lifting" can be used to lift of theorems from the
  2035 underlying "raw" type to the quotient type.  The example
  2036 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  2037 construction and provides a reasoning infrastructure for finite sets.
  2038 
  2039 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  2040 clash with new theory Quotient in Main HOL.
  2041 
  2042 * Moved the SMT binding into the main HOL session, eliminating
  2043 separate HOL-SMT session.
  2044 
  2045 * List membership infix mem operation is only an input abbreviation.
  2046 INCOMPATIBILITY.
  2047 
  2048 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  2049 for future developements; former Library/Word.thy is still present in
  2050 the AFP entry RSAPPS.
  2051 
  2052 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  2053 longer shadowed.  INCOMPATIBILITY.
  2054 
  2055 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  2056 INCOMPATIBILITY.
  2057 
  2058 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  2059 INCOMPATIBILITY.
  2060 
  2061 * Dropped normalizing_semiring etc; use the facts in semiring classes
  2062 instead.  INCOMPATIBILITY.
  2063 
  2064 * Dropped several real-specific versions of lemmas about floor and
  2065 ceiling; use the generic lemmas from theory "Archimedean_Field"
  2066 instead.  INCOMPATIBILITY.
  2067 
  2068   floor_number_of_eq         ~> floor_number_of
  2069   le_floor_eq_number_of      ~> number_of_le_floor
  2070   le_floor_eq_zero           ~> zero_le_floor
  2071   le_floor_eq_one            ~> one_le_floor
  2072   floor_less_eq_number_of    ~> floor_less_number_of
  2073   floor_less_eq_zero         ~> floor_less_zero
  2074   floor_less_eq_one          ~> floor_less_one
  2075   less_floor_eq_number_of    ~> number_of_less_floor
  2076   less_floor_eq_zero         ~> zero_less_floor
  2077   less_floor_eq_one          ~> one_less_floor
  2078   floor_le_eq_number_of      ~> floor_le_number_of
  2079   floor_le_eq_zero           ~> floor_le_zero
  2080   floor_le_eq_one            ~> floor_le_one
  2081   floor_subtract_number_of   ~> floor_diff_number_of
  2082   floor_subtract_one         ~> floor_diff_one
  2083   ceiling_number_of_eq       ~> ceiling_number_of
  2084   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  2085   ceiling_le_zero_eq         ~> ceiling_le_zero
  2086   ceiling_le_eq_one          ~> ceiling_le_one
  2087   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  2088   less_ceiling_eq_zero       ~> zero_less_ceiling
  2089   less_ceiling_eq_one        ~> one_less_ceiling
  2090   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  2091   ceiling_less_eq_zero       ~> ceiling_less_zero
  2092   ceiling_less_eq_one        ~> ceiling_less_one
  2093   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  2094   le_ceiling_eq_zero         ~> zero_le_ceiling
  2095   le_ceiling_eq_one          ~> one_le_ceiling
  2096   ceiling_subtract_number_of ~> ceiling_diff_number_of
  2097   ceiling_subtract_one       ~> ceiling_diff_one
  2098 
  2099 * Theory "Finite_Set": various folding_XXX locales facilitate the
  2100 application of the various fold combinators on finite sets.
  2101 
  2102 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  2103 provides abstract red-black tree type which is backed by "RBT_Impl" as
  2104 implementation.  INCOMPATIBILTY.
  2105 
  2106 * Theory Library/Coinductive_List has been removed -- superseded by
  2107 AFP/thys/Coinductive.
  2108 
  2109 * Theory PReal, including the type "preal" and related operations, has
  2110 been removed.  INCOMPATIBILITY.
  2111 
  2112 * Real: new development using Cauchy Sequences.
  2113 
  2114 * Split off theory "Big_Operators" containing setsum, setprod,
  2115 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  2116 
  2117 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  2118 "Int" etc.  INCOMPATIBILITY.
  2119 
  2120 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  2121 
  2122 * New set of rules "ac_simps" provides combined assoc / commute
  2123 rewrites for all interpretations of the appropriate generic locales.
  2124 
  2125 * Renamed theory "OrderedGroup" to "Groups" and split theory
  2126 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  2127 appropriate and more consistent names suitable for name prefixes
  2128 within the HOL theories.  INCOMPATIBILITY.
  2129 
  2130 * Some generic constants have been put to appropriate theories:
  2131   - less_eq, less: Orderings
  2132   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  2133   - inverse, divide: Rings
  2134 INCOMPATIBILITY.
  2135 
  2136 * More consistent naming of type classes involving orderings (and
  2137 lattices):
  2138 
  2139     lower_semilattice                   ~> semilattice_inf
  2140     upper_semilattice                   ~> semilattice_sup
  2141 
  2142     dense_linear_order                  ~> dense_linorder
  2143 
  2144     pordered_ab_group_add               ~> ordered_ab_group_add
  2145     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  2146     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  2147     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  2148     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  2149     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  2150     pordered_cancel_semiring            ~> ordered_cancel_semiring
  2151     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  2152     pordered_comm_ring                  ~> ordered_comm_ring
  2153     pordered_comm_semiring              ~> ordered_comm_semiring
  2154     pordered_ring                       ~> ordered_ring
  2155     pordered_ring_abs                   ~> ordered_ring_abs
  2156     pordered_semiring                   ~> ordered_semiring
  2157 
  2158     ordered_ab_group_add                ~> linordered_ab_group_add
  2159     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  2160     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  2161     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  2162     ordered_field                       ~> linordered_field
  2163     ordered_field_no_lb                 ~> linordered_field_no_lb
  2164     ordered_field_no_ub                 ~> linordered_field_no_ub
  2165     ordered_field_dense_linear_order    ~> dense_linordered_field
  2166     ordered_idom                        ~> linordered_idom
  2167     ordered_ring                        ~> linordered_ring
  2168     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  2169     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  2170     ordered_ring_strict                 ~> linordered_ring_strict
  2171     ordered_semidom                     ~> linordered_semidom
  2172     ordered_semiring                    ~> linordered_semiring
  2173     ordered_semiring_1                  ~> linordered_semiring_1
  2174     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  2175     ordered_semiring_strict             ~> linordered_semiring_strict
  2176 
  2177   The following slightly odd type classes have been moved to a
  2178   separate theory Library/Lattice_Algebras:
  2179 
  2180     lordered_ab_group_add               ~> lattice_ab_group_add
  2181     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  2182     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  2183     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  2184     lordered_ring                       ~> lattice_ring
  2185 
  2186 INCOMPATIBILITY.
  2187 
  2188 * Refined field classes:
  2189   - classes division_ring_inverse_zero, field_inverse_zero,
  2190     linordered_field_inverse_zero include rule inverse 0 = 0 --
  2191     subsumes former division_by_zero class;
  2192   - numerous lemmas have been ported from field to division_ring.
  2193 INCOMPATIBILITY.
  2194 
  2195 * Refined algebra theorem collections:
  2196   - dropped theorem group group_simps, use algebra_simps instead;
  2197   - dropped theorem group ring_simps, use field_simps instead;
  2198   - proper theorem collection field_simps subsumes former theorem
  2199     groups field_eq_simps and field_simps;
  2200   - dropped lemma eq_minus_self_iff which is a duplicate for
  2201     equal_neg_zero.
  2202 INCOMPATIBILITY.
  2203 
  2204 * Theory Finite_Set and List: some lemmas have been generalized from
  2205 sets to lattices:
  2206 
  2207   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  2208   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  2209   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  2210   union_Union_fold_union        ~> sup_Sup_fold_sup
  2211   Inter_fold_inter              ~> Inf_fold_inf
  2212   Union_fold_union              ~> Sup_fold_sup
  2213   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  2214   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  2215   INTER_fold_inter              ~> INFI_fold_inf
  2216   UNION_fold_union              ~> SUPR_fold_sup
  2217 
  2218 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  2219 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  2220 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  2221 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  2222 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  2223 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  2224 
  2225 * Reorganized theory Multiset: swapped notation of pointwise and
  2226 multiset order:
  2227 
  2228   - pointwise ordering is instance of class order with standard syntax
  2229     <= and <;
  2230   - multiset ordering has syntax <=# and <#; partial order properties
  2231     are provided by means of interpretation with prefix
  2232     multiset_order;
  2233   - less duplication, less historical organization of sections,
  2234     conversion from associations lists to multisets, rudimentary code
  2235     generation;
  2236   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  2237     if needed.
  2238 
  2239 Renamed:
  2240 
  2241   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  2242   multi_count_ext  ~>  multiset_ext
  2243   diff_union_inverse2  ~>  diff_union_cancelR
  2244 
  2245 INCOMPATIBILITY.
  2246 
  2247 * Theory Permutation: replaced local "remove" by List.remove1.
  2248 
  2249 * Code generation: ML and OCaml code is decorated with signatures.
  2250 
  2251 * Theory List: added transpose.
  2252 
  2253 * Library/Nat_Bijection.thy is a collection of bijective functions
  2254 between nat and other types, which supersedes the older libraries
  2255 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2256 
  2257   Constants:
  2258   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2259   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2260   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2261   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2262   Countable.pair_encode           ~> prod_encode
  2263   NatIso.prod2nat                 ~> prod_encode
  2264   NatIso.nat2prod                 ~> prod_decode
  2265   NatIso.sum2nat                  ~> sum_encode
  2266   NatIso.nat2sum                  ~> sum_decode
  2267   NatIso.list2nat                 ~> list_encode
  2268   NatIso.nat2list                 ~> list_decode
  2269   NatIso.set2nat                  ~> set_encode
  2270   NatIso.nat2set                  ~> set_decode
  2271 
  2272   Lemmas:
  2273   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2274   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2275   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2276   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2277   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2278   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2279   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2280   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2281   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2282   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2283   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2284   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2285   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2286 
  2287 * Sledgehammer:
  2288   - Renamed ATP commands:
  2289     atp_info     ~> sledgehammer running_atps
  2290     atp_kill     ~> sledgehammer kill_atps
  2291     atp_messages ~> sledgehammer messages
  2292     atp_minimize ~> sledgehammer minimize
  2293     print_atps   ~> sledgehammer available_atps
  2294     INCOMPATIBILITY.
  2295   - Added user's manual ("isabelle doc sledgehammer").
  2296   - Added option syntax and "sledgehammer_params" to customize
  2297     Sledgehammer's behavior.  See the manual for details.
  2298   - Modified the Isar proof reconstruction code so that it produces
  2299     direct proofs rather than proofs by contradiction.  (This feature
  2300     is still experimental.)
  2301   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2302     full-typed mode.
  2303   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2304 
  2305 * Nitpick:
  2306   - Added and implemented "binary_ints" and "bits" options.
  2307   - Added "std" option and implemented support for nonstandard models.
  2308   - Added and implemented "finitize" option to improve the precision
  2309     of infinite datatypes based on a monotonicity analysis.
  2310   - Added support for quotient types.
  2311   - Added support for "specification" and "ax_specification"
  2312     constructs.
  2313   - Added support for local definitions (for "function" and
  2314     "termination" proofs).
  2315   - Added support for term postprocessors.
  2316   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2317   - Improved efficiency of "destroy_constrs" optimization.
  2318   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2319     record getters.
  2320   - Fixed soundness bug related to higher-order constructors.
  2321   - Fixed soundness bug when "full_descrs" is enabled.
  2322   - Improved precision of set constructs.
  2323   - Added "atoms" option.
  2324   - Added cache to speed up repeated Kodkod invocations on the same
  2325     problems.
  2326   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2327     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2328     "SAT4J_Light".  INCOMPATIBILITY.
  2329   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2330     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2331   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2332 
  2333 * Method "induct" now takes instantiations of the form t, where t is not
  2334   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2335   If this is not intended, t has to be enclosed in parentheses.
  2336   By default, the equalities generated by definitional instantiations
  2337   are pre-simplified, which may cause parameters of inductive cases
  2338   to disappear, or may even delete some of the inductive cases.
  2339   Use "induct (no_simp)" instead of "induct" to restore the old
  2340   behaviour. The (no_simp) option is also understood by the "cases"
  2341   and "nominal_induct" methods, which now perform pre-simplification, too.
  2342   INCOMPATIBILITY.
  2343 
  2344 
  2345 *** HOLCF ***
  2346 
  2347 * Variable names in lemmas generated by the domain package have
  2348 changed; the naming scheme is now consistent with the HOL datatype
  2349 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2350 
  2351 * The domain package no longer defines the function "foo_copy" for
  2352 recursive domain "foo".  The reach lemma is now stated directly in
  2353 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2354 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2355 
  2356 * Most definedness lemmas generated by the domain package (previously
  2357 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2358 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2359 Proofs that used definedness lemmas as intro rules may break,
  2360 potential INCOMPATIBILITY.
  2361 
  2362 * Induction and casedist rules generated by the domain package now
  2363 declare proper case_names (one called "bottom", and one named for each
  2364 constructor).  INCOMPATIBILITY.
  2365 
  2366 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2367 rules are generated for each domain, INCOMPATIBILITY.
  2368 
  2369   foo_bar.reach       ~> foo.reach  bar.reach
  2370   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2371 
  2372 * Some lemmas generated by the domain package have been renamed for
  2373 consistency with the datatype package, INCOMPATIBILITY.
  2374 
  2375   foo.ind        ~> foo.induct
  2376   foo.finite_ind ~> foo.finite_induct
  2377   foo.coind      ~> foo.coinduct
  2378   foo.casedist   ~> foo.exhaust
  2379   foo.exhaust    ~> foo.nchotomy
  2380 
  2381 * For consistency with other definition packages, the fixrec package
  2382 now generates qualified theorem names, INCOMPATIBILITY.
  2383 
  2384   foo_simps  ~> foo.simps
  2385   foo_unfold ~> foo.unfold
  2386   foo_induct ~> foo.induct
  2387 
  2388 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2389 method and internal fixrec proofs now use the default simpset instead.
  2390 INCOMPATIBILITY.
  2391 
  2392 * The "contlub" predicate has been removed.  Proof scripts should use
  2393 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2394 
  2395 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2396 
  2397 * The constants cpair, cfst, and csnd have been removed in favor of
  2398 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2399 
  2400 
  2401 *** ML ***
  2402 
  2403 * Antiquotations for basic formal entities:
  2404 
  2405     @{class NAME}         -- type class
  2406     @{class_syntax NAME}  -- syntax representation of the above
  2407 
  2408     @{type_name NAME}     -- logical type
  2409     @{type_abbrev NAME}   -- type abbreviation
  2410     @{nonterminal NAME}   -- type of concrete syntactic category
  2411     @{type_syntax NAME}   -- syntax representation of any of the above
  2412 
  2413     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2414     @{const_abbrev NAME}  -- abbreviated constant
  2415     @{const_syntax NAME}  -- syntax representation of any of the above
  2416 
  2417 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2418 syntax constant (cf. 'syntax' command).
  2419 
  2420 * Antiquotation @{make_string} inlines a function to print arbitrary
  2421 values similar to the ML toplevel.  The result is compiler dependent
  2422 and may fall back on "?" in certain situations.
  2423 
  2424 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2425 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2426 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2427 not work with the asynchronous Isar document model.
  2428 
  2429 * Configuration options now admit dynamic default values, depending on
  2430 the context or even global references.
  2431 
  2432 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2433 uses an efficient external library if available (for Poly/ML).
  2434 
  2435 * Renamed some important ML structures, while keeping the old names
  2436 for some time as aliases within the structure Legacy:
  2437 
  2438   OuterKeyword  ~>  Keyword
  2439   OuterLex      ~>  Token
  2440   OuterParse    ~>  Parse
  2441   OuterSyntax   ~>  Outer_Syntax
  2442   PrintMode     ~>  Print_Mode
  2443   SpecParse     ~>  Parse_Spec
  2444   ThyInfo       ~>  Thy_Info
  2445   ThyLoad       ~>  Thy_Load
  2446   ThyOutput     ~>  Thy_Output
  2447   TypeInfer     ~>  Type_Infer
  2448 
  2449 Note that "open Legacy" simplifies porting of sources, but forgetting
  2450 to remove it again will complicate porting again in the future.
  2451 
  2452 * Most operations that refer to a global context are named
  2453 accordingly, e.g. Simplifier.global_context or
  2454 ProofContext.init_global.  There are some situations where a global
  2455 context actually works, but under normal circumstances one needs to
  2456 pass the proper local context through the code!
  2457 
  2458 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2459 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2460 Pretty.pp argument to merge, which is absent in the standard
  2461 Theory_Data version.
  2462 
  2463 * Sorts.certify_sort and derived "cert" operations for types and terms
  2464 no longer minimize sorts.  Thus certification at the boundary of the
  2465 inference kernel becomes invariant under addition of class relations,
  2466 which is an important monotonicity principle.  Sorts are now minimized
  2467 in the syntax layer only, at the boundary between the end-user and the
  2468 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2469 explicitly in rare situations.
  2470 
  2471 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2472 emphasize that this is in no way a standard operation.
  2473 INCOMPATIBILITY.
  2474 
  2475 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2476 usual for resolution.  Rare INCOMPATIBILITY.
  2477 
  2478 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2479 to emphasize that these only work in a global situation (which is
  2480 quite rare).
  2481 
  2482 * Curried take and drop in library.ML; negative length is interpreted
  2483 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2484 
  2485 * Proof terms: type substitutions on proof constants now use canonical
  2486 order of type variables.  INCOMPATIBILITY for tools working with proof
  2487 terms.
  2488 
  2489 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2490 may no longer carry premises.  User-level specifications are
  2491 transformed accordingly by Thm.add_axiom/add_def.
  2492 
  2493 
  2494 *** System ***
  2495 
  2496 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2497 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2498 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2499 
  2500 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2501 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2502 respectively.
  2503 
  2504 * Old lib/scripts/polyml-platform is superseded by the
  2505 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2506 variant, even on a 64 bit machine.  The following example setting
  2507 prefers 64 bit if available:
  2508 
  2509   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2510 
  2511 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2512 Isabelle/Scala layer for advanced prover interaction and integration.
  2513 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2514 component.
  2515 
  2516 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2517 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2518 similar to the default assignment of the document preparation system
  2519 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2520 provides some operations for direct access to the font without asking
  2521 the user for manual installation.
  2522 
  2523 
  2524 
  2525 New in Isabelle2009-1 (December 2009)
  2526 -------------------------------------
  2527 
  2528 *** General ***
  2529 
  2530 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2531 one backslash should be used, even in ML sources.
  2532 
  2533 
  2534 *** Pure ***
  2535 
  2536 * Locale interpretation propagates mixins along the locale hierarchy.
  2537 The currently only available mixins are the equations used to map
  2538 local definitions to terms of the target domain of an interpretation.
  2539 
  2540 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2541 loc" to print all interpretations of locale "loc" in the theory.
  2542 Interpretations in proofs are not shown.
  2543 
  2544 * Thoroughly revised locales tutorial.  New section on conditional
  2545 interpretation.
  2546 
  2547 * On instantiation of classes, remaining undefined class parameters
  2548 are formally declared.  INCOMPATIBILITY.
  2549 
  2550 
  2551 *** Document preparation ***
  2552 
  2553 * New generalized style concept for printing terms: @{foo (style) ...}
  2554 instead of @{foo_style style ...}  (old form is still retained for
  2555 backward compatibility).  Styles can be also applied for
  2556 antiquotations prop, term_type and typeof.
  2557 
  2558 
  2559 *** HOL ***
  2560 
  2561 * New proof method "smt" for a combination of first-order logic with
  2562 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2563 fixed-size bitvectors; there is also basic support for higher-order
  2564 features (esp. lambda abstractions).  It is an incomplete decision
  2565 procedure based on external SMT solvers using the oracle mechanism;
  2566 for the SMT solver Z3, this method is proof-producing.  Certificates
  2567 are provided to avoid calling the external solvers solely for
  2568 re-checking proofs.  Due to a remote SMT service there is no need for
  2569 installing SMT solvers locally.  See src/HOL/SMT.
  2570 
  2571 * New commands to load and prove verification conditions generated by
  2572 the Boogie program verifier or derived systems (e.g. the Verifying C
  2573 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2574 
  2575 * New counterexample generator tool 'nitpick' based on the Kodkod
  2576 relational model finder.  See src/HOL/Tools/Nitpick and
  2577 src/HOL/Nitpick_Examples.
  2578 
  2579 * New commands 'code_pred' and 'values' to invoke the predicate
  2580 compiler and to enumerate values of inductive predicates.
  2581 
  2582 * A tabled implementation of the reflexive transitive closure.
  2583 
  2584 * New implementation of quickcheck uses generic code generator;
  2585 default generators are provided for all suitable HOL types, records
  2586 and datatypes.  Old quickcheck can be re-activated importing theory
  2587 Library/SML_Quickcheck.
  2588 
  2589 * New testing tool Mirabelle for automated proof tools.  Applies
  2590 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2591 every proof step in a theory.  To be used in batch mode via the
  2592 "mirabelle" utility.
  2593 
  2594 * New proof method "sos" (sum of squares) for nonlinear real
  2595 arithmetic (originally due to John Harison). It requires theory
  2596 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2597 works well in practice on quantifier-free real arithmetic with +, -,
  2598 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2599 inequalities between polynomials.  It makes use of external
  2600 semidefinite programming solvers.  Method "sos" generates a
  2601 certificate that can be pasted into the proof thus avoiding the need
  2602 to call an external tool every time the proof is checked.  See
  2603 src/HOL/Library/Sum_Of_Squares.
  2604 
  2605 * New method "linarith" invokes existing linear arithmetic decision
  2606 procedure only.
  2607 
  2608 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2609 
  2610 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2611 Causes full type information to be output to the ATPs.  This slows
  2612 ATPs down considerably but eliminates a source of unsound "proofs"
  2613 that fail later.
  2614 
  2615 * New method "metisFT": A version of metis that uses full type
  2616 information in order to avoid failures of proof reconstruction.
  2617 
  2618 * New evaluator "approximate" approximates an real valued term using
  2619 the same method as the approximation method.
  2620 
  2621 * Method "approximate" now supports arithmetic expressions as
  2622 boundaries of intervals and implements interval splitting and Taylor
  2623 series expansion.
  2624 
  2625 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2626 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2627 
  2628 * New theory SupInf of the supremum and infimum operators for sets of
  2629 reals.
  2630 
  2631 * New theory Probability, which contains a development of measure
  2632 theory, eventually leading to Lebesgue integration and probability.
  2633 
  2634 * Extended Multivariate Analysis to include derivation and Brouwer's
  2635 fixpoint theorem.
  2636 
  2637 * Reorganization of number theory, INCOMPATIBILITY:
  2638   - new number theory development for nat and int, in theories Divides
  2639     and GCD as well as in new session Number_Theory
  2640   - some constants and facts now suffixed with _nat and _int
  2641     accordingly
  2642   - former session NumberTheory now named Old_Number_Theory, including
  2643     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2644   - moved theory Pocklington from src/HOL/Library to
  2645     src/HOL/Old_Number_Theory
  2646 
  2647 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2648 lcm of finite and infinite sets. It is shown that they form a complete
  2649 lattice.
  2650 
  2651 * Class semiring_div requires superclass no_zero_divisors and proof of
  2652 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2653 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2654 generalized to class semiring_div, subsuming former theorems
  2655 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2656 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2657 INCOMPATIBILITY.
  2658 
  2659 * Refinements to lattice classes and sets:
  2660   - less default intro/elim rules in locale variant, more default
  2661     intro/elim rules in class variant: more uniformity
  2662   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2663     le_inf_iff
  2664   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2665     sup_aci)
  2666   - renamed ACI to inf_sup_aci
  2667   - new class "boolean_algebra"
  2668   - class "complete_lattice" moved to separate theory
  2669     "Complete_Lattice"; corresponding constants (and abbreviations)
  2670     renamed and with authentic syntax:
  2671     Set.Inf ~>    Complete_Lattice.Inf
  2672     Set.Sup ~>    Complete_Lattice.Sup
  2673     Set.INFI ~>   Complete_Lattice.INFI
  2674     Set.SUPR ~>   Complete_Lattice.SUPR
  2675     Set.Inter ~>  Complete_Lattice.Inter
  2676     Set.Union ~>  Complete_Lattice.Union
  2677     Set.INTER ~>  Complete_Lattice.INTER
  2678     Set.UNION ~>  Complete_Lattice.UNION
  2679   - authentic syntax for
  2680     Set.Pow
  2681     Set.image
  2682   - mere abbreviations:
  2683     Set.empty               (for bot)
  2684     Set.UNIV                (for top)
  2685     Set.inter               (for inf, formerly Set.Int)
  2686     Set.union               (for sup, formerly Set.Un)
  2687     Complete_Lattice.Inter  (for Inf)
  2688     Complete_Lattice.Union  (for Sup)
  2689     Complete_Lattice.INTER  (for INFI)
  2690     Complete_Lattice.UNION  (for SUPR)
  2691   - object-logic definitions as far as appropriate
  2692 
  2693 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2694 Un_subset_iff are explicitly deleted as default simp rules; then also
  2695 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2696 deleted to achieve the desired effect.
  2697 
  2698 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2699 rules by default any longer; the same applies to min_max.inf_absorb1
  2700 etc.  INCOMPATIBILITY.
  2701 
  2702 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2703 pred_set_conv by default.  INCOMPATIBILITY.
  2704 
  2705 * Power operations on relations and functions are now one dedicated
  2706 constant "compow" with infix syntax "^^".  Power operation on
  2707 multiplicative monoids retains syntax "^" and is now defined generic
  2708 in class power.  INCOMPATIBILITY.
  2709 
  2710 * Relation composition "R O S" now has a more standard argument order:
  2711 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2712 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2713 break, since the O_assoc rule was not rewritten like this.  Fix using
  2714 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2715 
  2716 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2717 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2718 INCOMPATIBILITY.
  2719 
  2720 * Most rules produced by inductive and datatype package have mandatory
  2721 prefixes.  INCOMPATIBILITY.
  2722 
  2723 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2724 the attribute of the same name.  Each of the theorems in the list
  2725 DERIV_intros assumes composition with an additional function and
  2726 matches a variable to the derivative, which has to be solved by the
  2727 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2728 of most elementary terms.  Former Maclauren.DERIV_tac and
  2729 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2730 INCOMPATIBILITY.
  2731 
  2732 * Code generator attributes follow the usual underscore convention:
  2733     code_unfold     replaces    code unfold
  2734     code_post       replaces    code post
  2735     etc.
  2736   INCOMPATIBILITY.
  2737 
  2738 * Renamed methods:
  2739     sizechange -> size_change
  2740     induct_scheme -> induction_schema
  2741   INCOMPATIBILITY.
  2742 
  2743 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2744 INCOMPATIBILITY, use "undefined" directly.
  2745 
  2746 * Renamed theorems:
  2747     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2748     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2749     Suc_plus1 -> Suc_eq_plus1
  2750     *anti_sym -> *antisym*
  2751     vector_less_eq_def -> vector_le_def
  2752   INCOMPATIBILITY.
  2753 
  2754 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2755 INCOMPATIBILITY.
  2756 
  2757 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2758 INCOMPATIBILITY.
  2759 
  2760 
  2761 *** HOLCF ***
  2762 
  2763 * Theory Representable defines a class "rep" of domains that are
  2764 representable (via an ep-pair) in the universal domain type "udom".
  2765 Instances are provided for all type constructors defined in HOLCF.
  2766 
  2767 * The 'new_domain' command is a purely definitional version of the
  2768 domain package, for representable domains.  Syntax is identical to the
  2769 old domain package.  The 'new_domain' package also supports indirect
  2770 recursion using previously-defined type constructors.  See
  2771 src/HOLCF/ex/New_Domain.thy for examples.
  2772 
  2773 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2774 on the left-hand side of an equation, and then performs
  2775 simplification.  Rewriting is done using rules declared with the
  2776 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2777 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2778 
  2779 * The pattern-match compiler in 'fixrec' can now handle constructors
  2780 with HOL function types.  Pattern-match combinators for the Pair
  2781 constructor are pre-configured.
  2782 
  2783 * The 'fixrec' package now produces better fixed-point induction rules
  2784 for mutually-recursive definitions:  Induction rules have conclusions
  2785 of the form "P foo bar" instead of "P <foo, bar>".
  2786 
  2787 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2788 been renamed to "below".  The name "below" now replaces "less" in many
  2789 theorem names.  (Legacy theorem names using "less" are still supported
  2790 as well.)
  2791 
  2792 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2793 patterns can be used to generate strictness rules, or to make
  2794 functions more strict (much like the bang-patterns supported by the
  2795 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2796 examples.
  2797 
  2798 
  2799 *** ML ***
  2800 
  2801 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2802 errors and run-time exceptions, including detailed source positions.
  2803 
  2804 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2805 identified entries, with some additional information such as source
  2806 position, logical grouping etc.
  2807 
  2808 * Theory and context data is now introduced by the simplified and
  2809 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2810 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2811 copy operation) is still available for some time.
  2812 
  2813 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2814 provides a high-level programming interface to synchronized state
  2815 variables with atomic update.  This works via pure function
  2816 application within a critical section -- its runtime should be as
  2817 short as possible; beware of deadlocks if critical code is nested,
  2818 either directly or indirectly via other synchronized variables!
  2819 
  2820 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2821 wraps raw ML references, explicitly indicating their non-thread-safe
  2822 behaviour.  The Isar toplevel keeps this structure open, to
  2823 accommodate Proof General as well as quick and dirty interactive
  2824 experiments with references.
  2825 
  2826 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2827 parallel tactical reasoning.
  2828 
  2829 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2830 are similar to SUBPROOF, but are slightly more flexible: only the
  2831 specified parts of the subgoal are imported into the context, and the
  2832 body tactic may introduce new subgoals and schematic variables.
  2833 
  2834 * Old tactical METAHYPS, which does not observe the proof context, has
  2835 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2836 or Subgoal.FOCUS etc.
  2837 
  2838 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2839 functors have their own ML name space there is no point to mark them
  2840 separately.)  Minor INCOMPATIBILITY.
  2841 
  2842 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2843 
  2844 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2845 INCOMPATIBILITY.
  2846 
  2847 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2848 mode, which avoids critical setmp.
  2849 
  2850 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2851 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2852 Attrib/Method.setup introduced in Isabelle2009.
  2853 
  2854 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2855 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2856 last resort.  INCOMPATIBILITY.
  2857 
  2858 * Display.pretty_thm now requires a proper context (cf. former
  2859 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2860 or even Display.pretty_thm_without_context as last resort.
  2861 INCOMPATIBILITY.
  2862 
  2863 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2864 Syntax.pretty_typ/term directly, preferably with proper context
  2865 instead of global theory.
  2866 
  2867 
  2868 *** System ***
  2869 
  2870 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2871 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2872 usedir option -q.
  2873 
  2874 * Support for additional "Isabelle components" via etc/components, see
  2875 also the system manual.
  2876 
  2877 * The isabelle makeall tool now operates on all components with
  2878 IsaMakefile, not just hardwired "logics".
  2879 
  2880 * Removed "compress" option from isabelle-process and isabelle usedir;
  2881 this is always enabled.
  2882 
  2883 * Discontinued support for Poly/ML 4.x versions.
  2884 
  2885 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2886 on a given logic image.  This requires the lighttpd webserver and is
  2887 currently supported on Linux only.
  2888 
  2889 
  2890 
  2891 New in Isabelle2009 (April 2009)
  2892 --------------------------------
  2893 
  2894 *** General ***
  2895 
  2896 * Simplified main Isabelle executables, with less surprises on
  2897 case-insensitive file-systems (such as Mac OS).
  2898 
  2899   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2900     "isatool."
  2901 
  2902   - The former "isabelle" alias for "isabelle-process" has been
  2903     removed (should rarely occur to regular users).
  2904 
  2905   - The former "isabelle-interface" and its alias "Isabelle" have been
  2906     removed (interfaces are now regular Isabelle tools).
  2907 
  2908 Within scripts and make files, the Isabelle environment variables
  2909 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2910 respectively.  (The latter are still available as legacy feature.)
  2911 
  2912 The old isabelle-interface wrapper could react in confusing ways if
  2913 the interface was uninstalled or changed otherwise.  Individual
  2914 interface tool configuration is now more explicit, see also the
  2915 Isabelle system manual.  In particular, Proof General is now available
  2916 via "isabelle emacs".
  2917 
  2918 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2919 purge installed copies of Isabelle executables and re-run "isabelle
  2920 install -p ...", or use symlinks.
  2921 
  2922 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2923 old ~/isabelle, which was slightly non-standard and apt to cause
  2924 surprises on case-insensitive file-systems (such as Mac OS).
  2925 
  2926 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2927 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2928 care is required when using older releases of Isabelle.  Note that
  2929 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2930 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2931 
  2932 * Proofs of fully specified statements are run in parallel on
  2933 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2934 a regular 4-core machine, if the initial heap space is made reasonably
  2935 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2936 
  2937 * The main reference manuals ("isar-ref", "implementation", and
  2938 "system") have been updated and extended.  Formally checked references
  2939 as hyperlinks are now available uniformly.
  2940 
  2941 
  2942 *** Pure ***
  2943 
  2944 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2945 respects.  The most important changes are listed below.  See the
  2946 Tutorial on Locales ("locales" manual) for details.
  2947 
  2948 - In locale expressions, instantiation replaces renaming.  Parameters
  2949 must be declared in a for clause.  To aid compatibility with previous
  2950 parameter inheritance, in locale declarations, parameters that are not
  2951 'touched' (instantiation position "_" or omitted) are implicitly added
  2952 with their syntax at the beginning of the for clause.
  2953 
  2954 - Syntax from abbreviations and definitions in locales is available in
  2955 locale expressions and context elements.  The latter is particularly
  2956 useful in locale declarations.
  2957 
  2958 - More flexible mechanisms to qualify names generated by locale
  2959 expressions.  Qualifiers (prefixes) may be specified in locale
  2960 expressions, and can be marked as mandatory (syntax: "name!:") or
  2961 optional (syntax "name?:").  The default depends for plain "name:"
  2962 depends on the situation where a locale expression is used: in
  2963 commands 'locale' and 'sublocale' prefixes are optional, in
  2964 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2965 implicit qualifiers derived from the parameter names of a locale are
  2966 no longer generated.
  2967 
  2968 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2969 instantiation clause in "interpretation" and "interpret" (square
  2970 brackets) is no longer available.  Use locale expressions.
  2971 
  2972 - When converting proof scripts, mandatory qualifiers in
  2973 'interpretation' and 'interpret' should be retained by default, even
  2974 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2975 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2976 in locale expressions range over a single locale instance only.
  2977 
  2978 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2979 In existing theorem specifications replace the includes element by the
  2980 respective context elements of the included locale, omitting those
  2981 that are already present in the theorem specification.  Multiple
  2982 assume elements of a locale should be replaced by a single one
  2983 involving the locale predicate.  In the proof body, declarations (most
  2984 notably theorems) may be regained by interpreting the respective
  2985 locales in the proof context as required (command "interpret").
  2986 
  2987 If using "includes" in replacement of a target solely because the
  2988 parameter types in the theorem are not as general as in the target,
  2989 consider declaring a new locale with additional type constraints on
  2990 the parameters (context element "constrains").
  2991 
  2992 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2993 
  2994 - Locale interpretation commands no longer attempt to simplify goal.
  2995 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2996 methods intro_locales and unfold_locales to clarify.
  2997 
  2998 - Locale interpretation commands no longer accept interpretation
  2999 attributes.  INCOMPATIBILITY.
  3000 
  3001 * Class declaration: so-called "base sort" must not be given in import
  3002 list any longer, but is inferred from the specification.  Particularly
  3003 in HOL, write
  3004 
  3005     class foo = ...
  3006 
  3007 instead of
  3008 
  3009     class foo = type + ...
  3010 
  3011 * Class target: global versions of theorems stemming do not carry a
  3012 parameter prefix any longer.  INCOMPATIBILITY.
  3013 
  3014 * Class 'instance' command no longer accepts attached definitions.
  3015 INCOMPATIBILITY, use proper 'instantiation' target instead.
  3016 
  3017 * Recovered hiding of consts, which was accidentally broken in
  3018 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  3019 makes c inaccessible; consider using ``hide (open) const c'' instead.
  3020 
  3021 * Slightly more coherent Pure syntax, with updated documentation in
  3022 isar-ref manual.  Removed locales meta_term_syntax and
  3023 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  3024 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  3025 directly in regular applications.
  3026 
  3027 * There is a new syntactic category "float_const" for signed decimal
  3028 fractions (e.g. 123.45 or -123.45).
  3029 
  3030 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  3031 interface with 'setup' command instead.
  3032 
  3033 * Command 'local_setup' is similar to 'setup', but operates on a local
  3034 theory context.
  3035 
  3036 * The 'axiomatization' command now only works within a global theory
  3037 context.  INCOMPATIBILITY.
  3038 
  3039 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  3040 hypotheses.  Sorts required in the course of reasoning need to be
  3041 covered by the constraints in the initial statement, completed by the
  3042 type instance information of the background theory.  Non-trivial sort
  3043 hypotheses, which rarely occur in practice, may be specified via
  3044 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  3045 
  3046   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  3047 
  3048 The result contains an implicit sort hypotheses as before --
  3049 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  3050 normalization.
  3051 
  3052 * Generalized Isar history, with support for linear undo, direct state
  3053 addressing etc.
  3054 
  3055 * Changed defaults for unify configuration options:
  3056 
  3057   unify_trace_bound = 50 (formerly 25)
  3058   unify_search_bound = 60 (formerly 30)
  3059 
  3060 * Different bookkeeping for code equations (INCOMPATIBILITY):
  3061 
  3062   a) On theory merge, the last set of code equations for a particular
  3063      constant is taken (in accordance with the policy applied by other
  3064      parts of the code generator framework).
  3065 
  3066   b) Code equations stemming from explicit declarations (e.g. code
  3067      attribute) gain priority over default code equations stemming
  3068      from definition, primrec, fun etc.
  3069 
  3070 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  3071 
  3072 * Unified theorem tables for both code generators.  Thus [code
  3073 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  3074 
  3075 * Command 'find_consts' searches for constants based on type and name
  3076 patterns, e.g.
  3077 
  3078     find_consts "_ => bool"
  3079 
  3080 By default, matching is against subtypes, but it may be restricted to
  3081 the whole type.  Searching by name is possible.  Multiple queries are
  3082 conjunctive and queries may be negated by prefixing them with a
  3083 hyphen:
  3084 
  3085     find_consts strict: "_ => bool" name: "Int" -"int => int"
  3086 
  3087 * New 'find_theorems' criterion "solves" matches theorems that
  3088 directly solve the current goal (modulo higher-order unification).
  3089 
  3090 * Auto solve feature for main theorem statements: whenever a new goal
  3091 is stated, "find_theorems solves" is called; any theorems that could
  3092 solve the lemma directly are listed as part of the goal state.
  3093 Cf. associated options in Proof General Isabelle settings menu,
  3094 enabled by default, with reasonable timeout for pathological cases of
  3095 higher-order unification.
  3096 
  3097 
  3098 *** Document preparation ***
  3099 
  3100 * Antiquotation @{lemma} now imitates a regular terminal proof,
  3101 demanding keyword 'by' and supporting the full method expression
  3102 syntax just like the Isar command 'by'.
  3103 
  3104 
  3105 *** HOL ***
  3106 
  3107 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  3108 points Main and Complex_Main remain as before.
  3109 
  3110 * Logic image HOL-Plain provides a minimal HOL with the most important
  3111 tools available (inductive, datatype, primrec, ...).  This facilitates
  3112 experimentation and tool development.  Note that user applications
  3113 (and library theories) should never refer to anything below theory
  3114 Main, as before.
  3115 
  3116 * Logic image HOL-Main stops at theory Main, and thus facilitates
  3117 experimentation due to shorter build times.
  3118 
  3119 * Logic image HOL-NSA contains theories of nonstandard analysis which
  3120 were previously part of former HOL-Complex.  Entry point Hyperreal
  3121 remains valid, but theories formerly using Complex_Main should now use
  3122 new entry point Hypercomplex.
  3123 
  3124 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  3125 Posix processes.  Avoids potentially expensive forking of the ML
  3126 process.  New thread-based implementation also works on non-Unix
  3127 platforms (Cygwin).  Provers are no longer hardwired, but defined
  3128 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  3129 commands are covered in the isar-ref manual.
  3130 
  3131 * Wrapper scripts for remote SystemOnTPTP service allows to use
  3132 sledgehammer without local ATP installation (Vampire etc.). Other
  3133 provers may be included via suitable ML wrappers, see also
  3134 src/HOL/ATP_Linkup.thy.
  3135 
  3136 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  3137 menu.
  3138 
  3139 * The metis method no longer fails because the theorem is too trivial
  3140 (contains the empty clause).
  3141 
  3142 * The metis method now fails in the usual manner, rather than raising
  3143 an exception, if it determines that it cannot prove the theorem.
  3144 
  3145 * Method "coherent" implements a prover for coherent logic (see also
  3146 src/Tools/coherent.ML).
  3147 
  3148 * Constants "undefined" and "default" replace "arbitrary".  Usually
  3149 "undefined" is the right choice to replace "arbitrary", though
  3150 logically there is no difference.  INCOMPATIBILITY.
  3151 
  3152 * Command "value" now integrates different evaluation mechanisms.  The
  3153 result of the first successful evaluation mechanism is printed.  In
  3154 square brackets a particular named evaluation mechanisms may be
  3155 specified (currently, [SML], [code] or [nbe]).  See further
  3156 src/HOL/ex/Eval_Examples.thy.
  3157 
  3158 * Normalization by evaluation now allows non-leftlinear equations.
  3159 Declare with attribute [code nbe].
  3160 
  3161 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  3162 as the structured Isar versions "cases" and "induct", cf. the
  3163 corresponding "cases" and "induct" attributes.  Mutual induction rules
  3164 are now presented as a list of individual projections
  3165 (e.g. foo_bar.inducts for types foo and bar); the old format with
  3166 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  3167 rare situations a different rule is selected --- notably nested tuple
  3168 elimination instead of former prod.exhaust: use explicit (case_tac t
  3169 rule: prod.exhaust) here.
  3170 
  3171 * Attributes "cases", "induct", "coinduct" support "del" option.
  3172 
  3173 * Removed fact "case_split_thm", which duplicates "case_split".
  3174 
  3175 * The option datatype has been moved to a new theory Option.  Renamed
  3176 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  3177 
  3178 * New predicate "strict_mono" classifies strict functions on partial
  3179 orders.  With strict functions on linear orders, reasoning about
  3180 (in)equalities is facilitated by theorems "strict_mono_eq",
  3181 "strict_mono_less_eq" and "strict_mono_less".
  3182 
  3183 * Some set operations are now proper qualified constants with
  3184 authentic syntax.  INCOMPATIBILITY:
  3185 
  3186     op Int ~>   Set.Int
  3187     op Un ~>    Set.Un
  3188     INTER ~>    Set.INTER
  3189     UNION ~>    Set.UNION
  3190     Inter ~>    Set.Inter
  3191     Union ~>    Set.Union
  3192     {} ~>       Set.empty
  3193     UNIV ~>     Set.UNIV
  3194 
  3195 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  3196 theory Set.
  3197 
  3198 * Auxiliary class "itself" has disappeared -- classes without any
  3199 parameter are treated as expected by the 'class' command.
  3200 
  3201 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  3202 
  3203 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  3204 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  3205 
  3206 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  3207 method "approximation".  It proves formulas on real values by using
  3208 interval arithmetic.  In the formulas are also the transcendental
  3209 functions sin, cos, tan, atan, ln, exp and the constant pi are
  3210 allowed. For examples see
  3211 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  3212 
  3213 * Theory "Reflection" now resides in HOL/Library.
  3214 
  3215 * Entry point to Word library now simply named "Word".
  3216 INCOMPATIBILITY.
  3217 
  3218 * Made source layout more coherent with logical distribution
  3219 structure:
  3220 
  3221     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  3222     src/HOL/Library/Code_Message.thy ~> src/HOL/
  3223     src/HOL/Library/GCD.thy ~> src/HOL/
  3224     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  3225     src/HOL/Library/Parity.thy ~> src/HOL/
  3226     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  3227     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  3228     src/HOL/Real/Lubs.thy ~> src/HOL/
  3229     src/HOL/Real/PReal.thy ~> src/HOL/
  3230     src/HOL/Real/Rational.thy ~> src/HOL/
  3231     src/HOL/Real/RComplete.thy ~> src/HOL/
  3232     src/HOL/Real/RealDef.thy ~> src/HOL/
  3233     src/HOL/Real/RealPow.thy ~> src/HOL/
  3234     src/HOL/Real/Real.thy ~> src/HOL/
  3235     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  3236     src/HOL/Complex/Complex.thy ~> src/HOL/
  3237     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  3238     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  3239     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  3240     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  3241     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  3242     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  3243     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  3244     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  3245     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  3246     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  3247     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  3248     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  3249     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  3250     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  3251     src/HOL/Real/Float ~> src/HOL/Library/
  3252     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  3253     src/HOL/Real/RealVector.thy ~> src/HOL/
  3254 
  3255     src/HOL/arith_data.ML ~> src/HOL/Tools
  3256     src/HOL/hologic.ML ~> src/HOL/Tools
  3257     src/HOL/simpdata.ML ~> src/HOL/Tools
  3258     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3259     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3260     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3261     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3262     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3263     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3264     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3265 
  3266     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3267     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3268     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3269     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3270     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3271     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3272 
  3273 * If methods "eval" and "evaluation" encounter a structured proof
  3274 state with !!/==>, only the conclusion is evaluated to True (if
  3275 possible), avoiding strange error messages.
  3276 
  3277 * Method "sizechange" automates termination proofs using (a
  3278 modification of) the size-change principle.  Requires SAT solver.  See
  3279 src/HOL/ex/Termination.thy for examples.
  3280 
  3281 * Simplifier: simproc for let expressions now unfolds if bound
  3282 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3283 
  3284 * Method "arith": Linear arithmetic now ignores all inequalities when
  3285 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3286 
  3287 * New attribute "arith" for facts that should always be used
  3288 automatically by arithmetic. It is intended to be used locally in
  3289 proofs, e.g.
  3290 
  3291   assumes [arith]: "x > 0"
  3292 
  3293 Global usage is discouraged because of possible performance impact.
  3294 
  3295 * New classes "top" and "bot" with corresponding operations "top" and
  3296 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3297 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3298 
  3299 * Changed definition lemma "less_fun_def" in order to provide an
  3300 instance for preorders on functions; use lemma "less_le" instead.
  3301 INCOMPATIBILITY.
  3302 
  3303 * Theory Orderings: class "wellorder" moved here, with explicit
  3304 induction rule "less_induct" as assumption.  For instantiation of
  3305 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3306 INCOMPATIBILITY.
  3307 
  3308 * Theory Orderings: added class "preorder" as superclass of "order".
  3309 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3310 etc. slightly changed.  Some theorems named order_class.* now named
  3311 preorder_class.*.
  3312 
  3313 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3314 "diag" to "Id_on".
  3315 
  3316 * Theory Finite_Set: added a new fold combinator of type
  3317 
  3318   ('a => 'b => 'b) => 'b => 'a set => 'b
  3319 
  3320 Occasionally this is more convenient than the old fold combinator
  3321 which is now defined in terms of the new one and renamed to
  3322 fold_image.
  3323 
  3324 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3325 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3326 extended with further lemmas!).  At the moment both still exist but
  3327 the former will disappear at some point.
  3328 
  3329 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3330 class recpower.  Type-specific simp rules for various recpower types
  3331 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3332 
  3333 rat_power_0    -> power_0
  3334 rat_power_Suc  -> power_Suc
  3335 realpow_0      -> power_0
  3336 realpow_Suc    -> power_Suc
  3337 complexpow_0   -> power_0
  3338 complexpow_Suc -> power_Suc
  3339 power_poly_0   -> power_0
  3340 power_poly_Suc -> power_Suc
  3341 
  3342 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3343 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3344 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3345 of lemmas from Divides has been generalized from nat to class
  3346 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3347 renames resulting from duplicate elimination:
  3348 
  3349     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3350     zero_dvd_iff ~>         dvd_0_left_iff
  3351     dvd_0 ~>                dvd_0_right
  3352     DIVISION_BY_ZERO_DIV ~> div_by_0
  3353     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3354     mult_div ~>             div_mult_self2_is_id
  3355     mult_mod ~>             mod_mult_self2_is_0
  3356 
  3357 * Theory IntDiv: removed many lemmas that are instances of class-based
  3358 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3359 rename old lemmas as follows:
  3360 
  3361 dvd_diff               -> nat_dvd_diff
  3362 dvd_zminus_iff         -> dvd_minus_iff
  3363 mod_add1_eq            -> mod_add_eq
  3364 mod_mult1_eq           -> mod_mult_right_eq
  3365 mod_mult1_eq'          -> mod_mult_left_eq
  3366 mod_mult_distrib_mod   -> mod_mult_eq
  3367 nat_mod_add_left_eq    -> mod_add_left_eq
  3368 nat_mod_add_right_eq   -> mod_add_right_eq
  3369 nat_mod_div_trivial    -> mod_div_trivial
  3370 nat_mod_mod_trivial    -> mod_mod_trivial
  3371 zdiv_zadd_self1        -> div_add_self1
  3372 zdiv_zadd_self2        -> div_add_self2
  3373 zdiv_zmult_self1       -> div_mult_self2_is_id
  3374 zdiv_zmult_self2       -> div_mult_self1_is_id
  3375 zdvd_triv_left         -> dvd_triv_left
  3376 zdvd_triv_right        -> dvd_triv_right
  3377 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3378 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3379 zmod_zadd_left_eq      -> mod_add_left_eq
  3380 zmod_zadd_right_eq     -> mod_add_right_eq
  3381 zmod_zadd_self1        -> mod_add_self1
  3382 zmod_zadd_self2        -> mod_add_self2
  3383 zmod_zadd1_eq          -> mod_add_eq
  3384 zmod_zdiff1_eq         -> mod_diff_eq
  3385 zmod_zdvd_zmod         -> mod_mod_cancel
  3386 zmod_zmod_cancel       -> mod_mod_cancel
  3387 zmod_zmult_self1       -> mod_mult_self2_is_0
  3388 zmod_zmult_self2       -> mod_mult_self1_is_0
  3389 zmod_1                 -> mod_by_1
  3390 zdiv_1                 -> div_by_1
  3391 zdvd_abs1              -> abs_dvd_iff
  3392 zdvd_abs2              -> dvd_abs_iff
  3393 zdvd_refl              -> dvd_refl
  3394 zdvd_trans             -> dvd_trans
  3395 zdvd_zadd              -> dvd_add
  3396 zdvd_zdiff             -> dvd_diff
  3397 zdvd_zminus_iff        -> dvd_minus_iff
  3398 zdvd_zminus2_iff       -> minus_dvd_iff
  3399 zdvd_zmultD            -> dvd_mult_right
  3400 zdvd_zmultD2           -> dvd_mult_left
  3401 zdvd_zmult_mono        -> mult_dvd_mono
  3402 zdvd_0_right           -> dvd_0_right
  3403 zdvd_0_left            -> dvd_0_left_iff
  3404 zdvd_1_left            -> one_dvd
  3405 zminus_dvd_iff         -> minus_dvd_iff
  3406 
  3407 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3408 
  3409 * The real numbers offer decimal input syntax: 12.34 is translated
  3410 into 1234/10^2. This translation is not reversed upon output.
  3411 
  3412 * Theory Library/Polynomial defines an abstract type 'a poly of
  3413 univariate polynomials with coefficients of type 'a.  In addition to
  3414 the standard ring operations, it also supports div and mod.  Code
  3415 generation is also supported, using list-style constructors.
  3416 
  3417 * Theory Library/Inner_Product defines a class of real_inner for real
  3418 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3419 => real.  Class real_inner is a subclass of real_normed_vector from
  3420 theory RealVector.
  3421 
  3422 * Theory Library/Product_Vector provides instances for the product
  3423 type 'a * 'b of several classes from RealVector and Inner_Product.
  3424 Definitions of addition, subtraction, scalar multiplication, norms,
  3425 and inner products are included.
  3426 
  3427 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3428 addition to the field operations, numerals and case syntax are also
  3429 supported.
  3430 
  3431 * Theory Library/Diagonalize provides constructive version of Cantor's
  3432 first diagonalization argument.
  3433 
  3434 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3435 zlcm (for int); carried together from various gcd/lcm developements in
  3436 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3437 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3438 may recover tupled syntax as follows:
  3439 
  3440     hide (open) const gcd
  3441     abbreviation gcd where
  3442       "gcd == (%(a, b). GCD.gcd a b)"
  3443     notation (output)
  3444       GCD.gcd ("gcd '(_, _')")
  3445 
  3446 The same works for lcm, zgcd, zlcm.
  3447 
  3448 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3449 instantiations for algebraic structures.  Removed some duplicate
  3450 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3451 
  3452 * ML antiquotation @{code} takes a constant as argument and generates
  3453 corresponding code in background and inserts name of the corresponding
  3454 resulting ML value/function/datatype constructor binding in place.
  3455 All occurrences of @{code} with a single ML block are generated
  3456 simultaneously.  Provides a generic and safe interface for
  3457 instrumentalizing code generation.  See
  3458 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3459 In future you ought to refrain from ad-hoc compiling generated SML
  3460 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3461 cannot refer to constants for which user-defined serializations are
  3462 set.  Refer to the corresponding ML counterpart directly in that
  3463 cases.
  3464 
  3465 * Command 'rep_datatype': instead of theorem names the command now
  3466 takes a list of terms denoting the constructors of the type to be
  3467 represented as datatype.  The characteristic theorems have to be
  3468 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3469 have disappeared in favour of existing ones:
  3470 
  3471     unit_induct                 ~> unit.induct
  3472     prod_induct                 ~> prod.induct
  3473     sum_induct                  ~> sum.induct
  3474     Suc_Suc_eq                  ~> nat.inject
  3475     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3476 
  3477 
  3478 *** HOL-Algebra ***
  3479 
  3480 * New locales for orders and lattices where the equivalence relation
  3481 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3482 locales use a record structure with field eq for the equivalence.
  3483 
  3484 * New theory of factorial domains.
  3485 
  3486 * Units_l_inv and Units_r_inv are now simp rules by default.
  3487 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3488 and/or r_inv will now also require deletion of these lemmas.
  3489 
  3490 * Renamed the following theorems, INCOMPATIBILITY:
  3491 
  3492 UpperD ~> Upper_memD
  3493 LowerD ~> Lower_memD
  3494 least_carrier ~> least_closed
  3495 greatest_carrier ~> greatest_closed
  3496 greatest_Lower_above ~> greatest_Lower_below
  3497 one_zero ~> carrier_one_zero
  3498 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3499 
  3500 
  3501 *** HOL-Nominal ***
  3502 
  3503 * Nominal datatypes can now contain type-variables.
  3504 
  3505 * Commands 'nominal_inductive' and 'equivariance' work with local
  3506 theory targets.
  3507 
  3508 * Nominal primrec can now works with local theory targets and its
  3509 specification syntax now conforms to the general format as seen in
  3510 'inductive' etc.
  3511 
  3512 * Method "perm_simp" honours the standard simplifier attributes
  3513 (no_asm), (no_asm_use) etc.
  3514 
  3515 * The new predicate #* is defined like freshness, except that on the
  3516 left hand side can be a set or list of atoms.
  3517 
  3518 * Experimental command 'nominal_inductive2' derives strong induction
  3519 principles for inductive definitions.  In contrast to
  3520 'nominal_inductive', which can only deal with a fixed number of
  3521 binders, it can deal with arbitrary expressions standing for sets of
  3522 atoms to be avoided.  The only inductive definition we have at the
  3523 moment that needs this generalisation is the typing rule for Lets in
  3524 the algorithm W:
  3525 
  3526  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3527  -----------------------------------------------------------------
  3528          Gamma |- Let x be t1 in t2 : T2
  3529 
  3530 In this rule one wants to avoid all the binders that are introduced by
  3531 "close Gamma T1".  We are looking for other examples where this
  3532 feature might be useful.  Please let us know.
  3533 
  3534 
  3535 *** HOLCF ***
  3536 
  3537 * Reimplemented the simplification procedure for proving continuity
  3538 subgoals.  The new simproc is extensible; users can declare additional
  3539 continuity introduction rules with the attribute [cont2cont].
  3540 
  3541 * The continuity simproc now uses a different introduction rule for
  3542 solving continuity subgoals on terms with lambda abstractions.  In
  3543 some rare cases the new simproc may fail to solve subgoals that the
  3544 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3545 Potential INCOMPATIBILITY.
  3546 
  3547 * Command 'fixrec': specification syntax now conforms to the general
  3548 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3549 examples.  INCOMPATIBILITY.
  3550 
  3551 
  3552 *** ZF ***
  3553 
  3554 * Proof of Zorn's Lemma for partial orders.
  3555 
  3556 
  3557 *** ML ***
  3558 
  3559 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3560 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3561 depends on multithreading, so timouts will not work before Poly/ML
  3562 5.2.1!
  3563 
  3564 * High-level support for concurrent ML programming, see
  3565 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3566 particularly convenient to organize independent functional
  3567 computations.  The concept of "synchronized variables" provides a
  3568 higher-order interface for components with shared state, avoiding the
  3569 delicate details of mutexes and condition variables.  (Requires
  3570 Poly/ML 5.2.1 or later.)
  3571 
  3572 * ML bindings produced via Isar commands are stored within the Isar
  3573 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3574 become thread-safe and work with undo as expected (concerning
  3575 top-level bindings, not side-effects on global references).
  3576 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3577 compiler at runtime; really global bindings need to be given outside a
  3578 theory.  (Requires Poly/ML 5.2 or later.)
  3579 
  3580 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3581 context.  Top-level ML bindings are stored within the proof context in
  3582 a purely sequential fashion, disregarding the nested proof structure.
  3583 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3584 proof.  (Requires Poly/ML 5.2 or later.)
  3585 
  3586 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3587 and Method.setup, as well as Isar commands 'attribute_setup' and
  3588 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3589 existing code accordingly, or use plain 'setup' together with old
  3590 Method.add_method.
  3591 
  3592 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3593 to 'a -> thm, while results are always tagged with an authentic oracle
  3594 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3595 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3596 accordingly.  Note that extra performance may be gained by producing
  3597 the cterm carefully, avoiding slow Thm.cterm_of.
  3598 
  3599 * Simplified interface for defining document antiquotations via
  3600 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3601 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3602 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3603 examples.
  3604 
  3605 * More systematic treatment of long names, abstract name bindings, and
  3606 name space operations.  Basic operations on qualified names have been
  3607 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3608 Long_Name.append.  Old type bstring has been mostly replaced by
  3609 abstract type binding (see structure Binding), which supports precise
  3610 qualification by packages and local theory targets, as well as proper
  3611 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3612 bstring values into Binding.name, or better pass through abstract
  3613 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3614 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3615 
  3616 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3617 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3618 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3619 
  3620 * Disposed old type and term read functions (Sign.read_def_typ,
  3621 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3622 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3623 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3624 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3625 resort for legacy applications.
  3626 
  3627 * Disposed old declarations, tactics, tactic combinators that refer to
  3628 the simpset or claset of an implicit theory (such as Addsimps,
  3629 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3630 embedded ML text, or local_simpset_of with a proper context passed as
  3631 explicit runtime argument.
  3632 
  3633 * Rules and tactics that read instantiations (read_instantiate,
  3634 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3635 context, which is required for parsing and type-checking.  Moreover,
  3636 the variables are specified as plain indexnames, not string encodings
  3637 thereof.  INCOMPATIBILITY.
  3638 
  3639 * Generic Toplevel.add_hook interface allows to analyze the result of
  3640 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3641 for theorem dependency output of transactions resulting in a new
  3642 theory state.
  3643 
  3644 * ML antiquotations: block-structured compilation context indicated by
  3645 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3646 
  3647   @{binding name}                         - basic name binding
  3648   @{let ?pat = term}                      - term abbreviation (HO matching)
  3649   @{note name = fact}                     - fact abbreviation
  3650   @{thm fact}                             - singleton fact (with attributes)
  3651   @{thms fact}                            - general fact (with attributes)
  3652   @{lemma prop by method}                 - singleton goal
  3653   @{lemma prop by meth1 meth2}            - singleton goal
  3654   @{lemma prop1 ... propN by method}      - general goal
  3655   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3656   @{lemma (open) ...}                     - open derivation
  3657 
  3658 
  3659 *** System ***
  3660 
  3661 * The Isabelle "emacs" tool provides a specific interface to invoke
  3662 Proof General / Emacs, with more explicit failure if that is not
  3663 installed (the old isabelle-interface script silently falls back on
  3664 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3665 installation location of the Proof General distribution.
  3666 
  3667 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3668 the Isabelle process into a JVM/Scala application.  See
  3669 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3670 process wrapper has been discontinued.)
  3671 
  3672 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3673 
  3674 * Various status messages (with exact source position information) are
  3675 emitted, if proper markup print mode is enabled.  This allows
  3676 user-interface components to provide detailed feedback on internal
  3677 prover operations.
  3678 
  3679 
  3680 
  3681 New in Isabelle2008 (June 2008)
  3682 -------------------------------
  3683 
  3684 *** General ***
  3685 
  3686 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3687 and updated, with formally checked references as hyperlinks.
  3688 
  3689 * Theory loader: use_thy (and similar operations) no longer set the
  3690 implicit ML context, which was occasionally hard to predict and in
  3691 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3692 provides a proper context already.
  3693 
  3694 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3695 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3696 'use' within a theory file will do the job.
  3697 
  3698 * Name space merge now observes canonical order, i.e. the second space
  3699 is inserted into the first one, while existing entries in the first
  3700 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3701 swap theory imports.
  3702 
  3703 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3704 INCOMPATIBILITY in identifier syntax etc.
  3705 
  3706 * Outer syntax: string tokens no longer admit escaped white space,
  3707 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3708 white space without escapes.
  3709 
  3710 * Outer syntax: string tokens may contain arbitrary character codes
  3711 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3712 "foo_bar".
  3713 
  3714 
  3715 *** Pure ***
  3716 
  3717 * Context-dependent token translations.  Default setup reverts locally
  3718 fixed variables, and adds hilite markup for undeclared frees.
  3719 
  3720 * Unused theorems can be found using the new command 'unused_thms'.
  3721 There are three ways of invoking it:
  3722 
  3723 (1) unused_thms
  3724      Only finds unused theorems in the current theory.
  3725 
  3726 (2) unused_thms thy_1 ... thy_n -
  3727      Finds unused theorems in the current theory and all of its ancestors,
  3728      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3729 
  3730 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3731      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3732      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3733      their ancestors.
  3734 
  3735 In order to increase the readability of the list produced by
  3736 unused_thms, theorems that have been created by a particular instance
  3737 of a theory command such as 'inductive' or 'function' are considered
  3738 to belong to the same "group", meaning that if at least one theorem in
  3739 this group is used, the other theorems in the same group are no longer
  3740 reported as unused.  Moreover, if all theorems in the group are
  3741 unused, only one theorem in the group is displayed.
  3742 
  3743 Note that proof objects have to be switched on in order for
  3744 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3745 usually the case when using Proof General with the default settings).
  3746 
  3747 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3748 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3749 duplicate fact bindings, or even accidental fact duplications.  Note
  3750 that tools may maintain dynamically scoped facts systematically, using
  3751 PureThy.add_thms_dynamic.
  3752 
  3753 * Command 'hide' now allows to hide from "fact" name space as well.
  3754 
  3755 * Eliminated destructive theorem database, simpset, claset, and
  3756 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3757 update of theories within ML code.
  3758 
  3759 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3760 INCOMPATIBILITY, object-logics depending on former Pure require
  3761 additional setup PureThy.old_appl_syntax_setup; object-logics
  3762 depending on former CPure need to refer to Pure.
  3763 
  3764 * Commands 'use' and 'ML' are now purely functional, operating on
  3765 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3766 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3767 INCOMPATIBILITY.
  3768 
  3769 * Command 'setup': discontinued implicit version with ML reference.
  3770 
  3771 * Instantiation target allows for simultaneous specification of class
  3772 instance operations together with an instantiation proof.
  3773 Type-checking phase allows to refer to class operations uniformly.
  3774 See src/HOL/Complex/Complex.thy for an Isar example and
  3775 src/HOL/Library/Eval.thy for an ML example.
  3776 
  3777 * Indexing of literal facts: be more serious about including only
  3778 facts from the visible specification/proof context, but not the
  3779 background context (locale etc.).  Affects `prop` notation and method
  3780 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3781 situations.
  3782 
  3783 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3784 "(open)" option, which used to expose internal bound variables to the
  3785 proof text.
  3786 
  3787 * Isar statements: removed obsolete case "rule_context".
  3788 INCOMPATIBILITY, better use explicit fixes/assumes.
  3789 
  3790 * Locale proofs: default proof step now includes 'unfold_locales';
  3791 hence 'proof' without argument may be used to unfold locale
  3792 predicates.
  3793 
  3794 
  3795 *** Document preparation ***
  3796 
  3797 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3798 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3799 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3800 spot); renamed link color from "darkblue" to "linkcolor" (default
  3801 value unchanged, can be redefined via \definecolor); no longer sets
  3802 "a4paper" option (unnecessary or even intrusive).
  3803 
  3804 * Antiquotation @{lemma A method} proves proposition A by the given
  3805 method (either a method name or a method name plus (optional) method
  3806 arguments in parentheses) and prints A just like @{prop A}.
  3807 
  3808 
  3809 *** HOL ***
  3810 
  3811 * New primrec package.  Specification syntax conforms in style to
  3812 definition/function/....  No separate induction rule is provided.  The
  3813 "primrec" command distinguishes old-style and new-style specifications
  3814 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3815 When adjusting theories, beware: constants stemming from new-style
  3816 primrec specifications have authentic syntax.
  3817 
  3818 * Metis prover is now an order of magnitude faster, and also works
  3819 with multithreading.
  3820 
  3821 * Metis: the maximum number of clauses that can be produced from a
  3822 theorem is now given by the attribute max_clauses.  Theorems that
  3823 exceed this number are ignored, with a warning printed.
  3824 
  3825 * Sledgehammer no longer produces structured proofs by default. To
  3826 enable, declare [[sledgehammer_full = true]].  Attributes
  3827 reconstruction_modulus, reconstruction_sorts renamed
  3828 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3829 
  3830 * Method "induct_scheme" derives user-specified induction rules
  3831 from well-founded induction and completeness of patterns. This factors
  3832 out some operations that are done internally by the function package
  3833 and makes them available separately.  See
  3834 src/HOL/ex/Induction_Scheme.thy for examples.
  3835 
  3836 * More flexible generation of measure functions for termination
  3837 proofs: Measure functions can be declared by proving a rule of the
  3838 form "is_measure f" and giving it the [measure_function] attribute.
  3839 The "is_measure" predicate is logically meaningless (always true), and
  3840 just guides the heuristic.  To find suitable measure functions, the
  3841 termination prover sets up the goal "is_measure ?f" of the appropriate
  3842 type and generates all solutions by prolog-style backwards proof using
  3843 the declared rules.
  3844 
  3845 This setup also deals with rules like 
  3846 
  3847   "is_measure f ==> is_measure (list_size f)"
  3848 
  3849 which accommodates nested datatypes that recurse through lists.
  3850 Similar rules are predeclared for products and option types.
  3851 
  3852 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3853 
  3854   INCOMPATIBILITIES:
  3855 
  3856   - Definitions of overloaded constants on sets have to be replaced by
  3857     definitions on => and bool.
  3858 
  3859   - Some definitions of overloaded operators on sets can now be proved
  3860     using the definitions of the operators on => and bool.  Therefore,
  3861     the following theorems have been renamed:
  3862 
  3863       subset_def   -> subset_eq
  3864       psubset_def  -> psubset_eq
  3865       set_diff_def -> set_diff_eq
  3866       Compl_def    -> Compl_eq
  3867       Sup_set_def  -> Sup_set_eq
  3868       Inf_set_def  -> Inf_set_eq
  3869       sup_set_def  -> sup_set_eq
  3870       inf_set_def  -> inf_set_eq
  3871 
  3872   - Due to the incompleteness of the HO unification algorithm, some
  3873     rules such as subst may require manual instantiation, if some of
  3874     the unknowns in the rule is a set.
  3875 
  3876   - Higher order unification and forward proofs:
  3877     The proof pattern
  3878 
  3879       have "P (S::'a set)" <...>
  3880       then have "EX S. P S" ..
  3881 
  3882     no longer works (due to the incompleteness of the HO unification
  3883     algorithm) and must be replaced by the pattern
  3884 
  3885       have "EX S. P S"
  3886       proof
  3887         show "P S" <...>
  3888       qed
  3889 
  3890   - Calculational reasoning with subst (or similar rules):
  3891     The proof pattern
  3892 
  3893       have "P (S::'a set)" <...>
  3894       also have "S = T" <...>
  3895       finally have "P T" .
  3896 
  3897     no longer works (for similar reasons as the previous example) and
  3898     must be replaced by something like
  3899 
  3900       have "P (S::'a set)" <...>
  3901       moreover have "S = T" <...>
  3902       ultimately have "P T" by simp
  3903 
  3904   - Tactics or packages written in ML code:
  3905     Code performing pattern matching on types via
  3906 
  3907       Type ("set", [T]) => ...
  3908 
  3909     must be rewritten. Moreover, functions like strip_type or
  3910     binder_types no longer return the right value when applied to a
  3911     type of the form
  3912 
  3913       T1 => ... => Tn => U => bool
  3914 
  3915     rather than
  3916 
  3917       T1 => ... => Tn => U set
  3918 
  3919 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3920 Wellfounded_Relations to theory Wellfounded.
  3921 
  3922 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3923 
  3924 * Class finite no longer treats UNIV as class parameter.  Use class
  3925 enum from theory Library/Enum instead to achieve a similar effect.
  3926 INCOMPATIBILITY.
  3927 
  3928 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3929 and "Cons".  INCOMPATIBILITY.
  3930 
  3931 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3932 Potential INCOMPATIBILITY.
  3933 
  3934 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3935 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3936 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3937 
  3938 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3939 the same name in theory Orderings:
  3940 
  3941   less_trans
  3942   less_linear
  3943   le_imp_less_or_eq
  3944   le_less_trans
  3945   less_le_trans
  3946   less_not_sym
  3947   less_asym
  3948 
  3949 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3950 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3951 and different variable names.
  3952 
  3953 * Library/Option_ord.thy: Canonical order on option type.
  3954 
  3955 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3956 finite maps.
  3957 
  3958 * Library/Countable.thy: Type class for countable types.
  3959 
  3960 * Theory Int: The representation of numerals has changed.  The infix
  3961 operator BIT and the bit datatype with constructors B0 and B1 have
  3962 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3963 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3964 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3965 accordingly.
  3966 
  3967 * Theory Nat: definition of <= and < on natural numbers no longer
  3968 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3969 le_def and less_def have disappeared.  Consider lemmas not_less
  3970 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3971 
  3972 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3973 (whose purpose mainly is for various fold_set functionals) have been
  3974 abandoned in favor of the existing algebraic classes
  3975 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3976 lower_semilattice (resp. upper_semilattice) and linorder.
  3977 INCOMPATIBILITY.
  3978 
  3979 * Theory Transitive_Closure: induct and cases rules now declare proper
  3980 case_names ("base" and "step").  INCOMPATIBILITY.
  3981 
  3982 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3983 lattices.  The form set-specific version is available as
  3984 Inductive.lfp_ordinal_induct_set.
  3985 
  3986 * Renamed theorems "power.simps" to "power_int.simps".
  3987 INCOMPATIBILITY.
  3988 
  3989 * Class semiring_div provides basic abstract properties of semirings
  3990 with division and modulo operations.  Subsumes former class dvd_mod.
  3991 
  3992 * Merged theories IntDef, Numeral and IntArith into unified theory
  3993 Int.  INCOMPATIBILITY.
  3994 
  3995 * Theory Library/Code_Index: type "index" now represents natural
  3996 numbers rather than integers.  INCOMPATIBILITY.
  3997 
  3998 * New class "uminus" with operation "uminus" (split of from class
  3999 "minus" which now only has operation "minus", binary).
  4000 INCOMPATIBILITY.
  4001 
  4002 * Constants "card", "internal_split", "option_map" now with authentic
  4003 syntax.  INCOMPATIBILITY.
  4004 
  4005 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  4006 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  4007 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  4008 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  4009 Sup_set_def, le_def, less_def, option_map_def now with object
  4010 equality.  INCOMPATIBILITY.
  4011 
  4012 * Records. Removed K_record, and replaced it by pure lambda term
  4013 %x. c. The simplifier setup is now more robust against eta expansion.
  4014 INCOMPATIBILITY: in cases explicitly referring to K_record.
  4015 
  4016 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  4017 
  4018 * Library/ListVector: new theory of arithmetic vector operations.
  4019 
  4020 * Library/Order_Relation: new theory of various orderings as sets of
  4021 pairs.  Defines preorders, partial orders, linear orders and
  4022 well-orders on sets and on types.
  4023 
  4024 
  4025 *** ZF ***
  4026 
  4027 * Renamed some theories to allow to loading both ZF and HOL in the
  4028 same session:
  4029 
  4030   Datatype  -> Datatype_ZF
  4031   Inductive -> Inductive_ZF
  4032   Int       -> Int_ZF
  4033   IntDiv    -> IntDiv_ZF
  4034   Nat       -> Nat_ZF
  4035   List      -> List_ZF
  4036   Main      -> Main_ZF
  4037 
  4038 INCOMPATIBILITY: ZF theories that import individual theories below
  4039 Main might need to be adapted.  Regular theory Main is still
  4040 available, as trivial extension of Main_ZF.
  4041 
  4042 
  4043 *** ML ***
  4044 
  4045 * ML within Isar: antiquotation @{const name} or @{const
  4046 name(typargs)} produces statically-checked Const term.
  4047 
  4048 * Functor NamedThmsFun: data is available to the user as dynamic fact
  4049 (of the same name).  Removed obsolete print command.
  4050 
  4051 * Removed obsolete "use_legacy_bindings" function.
  4052 
  4053 * The ``print mode'' is now a thread-local value derived from a global
  4054 template (the former print_mode reference), thus access becomes
  4055 non-critical.  The global print_mode reference is for session
  4056 management only; user-code should use print_mode_value,
  4057 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  4058 
  4059 * Functions system/system_out provide a robust way to invoke external
  4060 shell commands, with propagation of interrupts (requires Poly/ML
  4061 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  4062 
  4063 
  4064 *** System ***
  4065 
  4066 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  4067 in accordance with Proof General 3.7, which prefers GNU emacs.
  4068 
  4069 * isatool tty runs Isabelle process with plain tty interaction;
  4070 optional line editor may be specified via ISABELLE_LINE_EDITOR
  4071 setting, the default settings attempt to locate "ledit" and "rlwrap".
  4072 
  4073 * isatool browser now works with Cygwin as well, using general
  4074 "javapath" function defined in Isabelle process environment.
  4075 
  4076 * YXML notation provides a simple and efficient alternative to
  4077 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  4078 isatool yxml as described in the Isabelle system manual.
  4079 
  4080 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  4081 provides general wrapper for managing an Isabelle process in a robust
  4082 fashion, with ``cooked'' output from stdin/stderr.
  4083 
  4084 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  4085 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  4086 
  4087 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  4088 way of changing the user's settings is via
  4089 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  4090 script.
  4091 
  4092 * Multithreading.max_threads := 0 refers to the number of actual CPU
  4093 cores of the underlying machine, which is a good starting point for
  4094 optimal performance tuning.  The corresponding usedir option -M allows
  4095 "max" as an alias for "0".  WARNING: does not work on certain versions
  4096 of Mac OS (with Poly/ML 5.1).
  4097 
  4098 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  4099 adverse effect of Isabelle flooding interactive front-ends (notably
  4100 ProofGeneral / XEmacs).
  4101 
  4102 
  4103 
  4104 New in Isabelle2007 (November 2007)
  4105 -----------------------------------
  4106 
  4107 *** General ***
  4108 
  4109 * More uniform information about legacy features, notably a
  4110 warning/error of "Legacy feature: ...", depending on the state of the
  4111 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  4112 legacy features will disappear eventually.
  4113 
  4114 * Theory syntax: the header format ``theory A = B + C:'' has been
  4115 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  4116 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  4117 
  4118 * Theory syntax: the old non-Isar theory file format has been
  4119 discontinued altogether.  Note that ML proof scripts may still be used
  4120 with Isar theories; migration is usually quite simple with the ML
  4121 function use_legacy_bindings.  INCOMPATIBILITY.
  4122 
  4123 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  4124 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  4125 quotes.
  4126 
  4127 * Theory loader: be more serious about observing the static theory
  4128 header specifications (including optional directories), but not the
  4129 accidental file locations of previously successful loads.  The strict
  4130 update policy of former update_thy is now already performed by
  4131 use_thy, so the former has been removed; use_thys updates several
  4132 theories simultaneously, just as 'imports' within a theory header
  4133 specification, but without merging the results.  Potential
  4134 INCOMPATIBILITY: may need to refine theory headers and commands
  4135 ROOT.ML which depend on load order.
  4136 
  4137 * Theory loader: optional support for content-based file
  4138 identification, instead of the traditional scheme of full physical
  4139 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  4140 (cf. the system manual).  The new scheme allows to work with
  4141 non-finished theories in persistent session images, such that source
  4142 files may be moved later on without requiring reloads.
  4143 
  4144 * Theory loader: old-style ML proof scripts being *attached* to a thy
  4145 file (with the same base name as the theory) are considered a legacy
  4146 feature, which will disappear eventually. Even now, the theory loader
  4147 no longer maintains dependencies on such files.
  4148 
  4149 * Syntax: the scope for resolving ambiguities via type-inference is
  4150 now limited to individual terms, instead of whole simultaneous
  4151 specifications as before. This greatly reduces the complexity of the
  4152 syntax module and improves flexibility by separating parsing and
  4153 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  4154 'fixes' etc.) are required in rare situations.
  4155 
  4156 * Syntax: constants introduced by new-style packages ('definition',
  4157 'abbreviation' etc.) are passed through the syntax module in
  4158 ``authentic mode''. This means that associated mixfix annotations
  4159 really stick to such constants, independently of potential name space
  4160 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  4161 trees are represented slightly differently, may need to adapt syntax
  4162 translations accordingly. Use CONST marker in 'translations' and
  4163 @{const_syntax} antiquotation in 'parse_translation' etc.
  4164 
  4165 * Legacy goal package: reduced interface to the bare minimum required
  4166 to keep existing proof scripts running.  Most other user-level
  4167 functions are now part of the OldGoals structure, which is *not* open
  4168 by default (consider isatool expandshort before open OldGoals).
  4169 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  4170 these tend to cause confusion about the actual goal (!) context being
  4171 used here, which is not necessarily the same as the_context().
  4172 
  4173 * Command 'find_theorems': supports "*" wild-card in "name:"
  4174 criterion; "with_dups" option.  Certain ProofGeneral versions might
  4175 support a specific search form (see ProofGeneral/CHANGES).
  4176 
  4177 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  4178 by default, which means that "prems" (and also "fixed variables") are
  4179 suppressed from proof state output.  Note that the ProofGeneral
  4180 settings mechanism allows to change and save options persistently, but
  4181 older versions of Isabelle will fail to start up if a negative prems
  4182 limit is imposed.
  4183 
  4184 * Local theory targets may be specified by non-nested blocks of
  4185 ``context/locale/class ... begin'' followed by ``end''.  The body may
  4186 contain definitions, theorems etc., including any derived mechanism
  4187 that has been implemented on top of these primitives.  This concept
  4188 generalizes the existing ``theorem (in ...)'' towards more versatility
  4189 and scalability.
  4190 
  4191 * Proof General interface: proper undo of final 'end' command;
  4192 discontinued Isabelle/classic mode (ML proof scripts).
  4193 
  4194 
  4195 *** Document preparation ***
  4196 
  4197 * Added antiquotation @{theory name} which prints the given name,
  4198 after checking that it refers to a valid ancestor theory in the
  4199 current context.
  4200 
  4201 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  4202 check the given source text as ML type/structure, printing verbatim.
  4203 
  4204 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  4205 "c args == rhs" given in the current context.  (Any number of
  4206 arguments may be given on the LHS.)
  4207 
  4208 
  4209 *** Pure ***
  4210 
  4211 * The 'class' package offers a combination of axclass and locale to
  4212 achieve Haskell-like type classes in Isabelle.  Definitions and
  4213 theorems within a class context produce both relative results (with
  4214 implicit parameters according to the locale context), and polymorphic
  4215 constants with qualified polymorphism (according to the class
  4216 context).  Within the body context of a 'class' target, a separate
  4217 syntax layer ("user space type system") takes care of converting
  4218 between global polymorphic consts and internal locale representation.
  4219 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  4220 "isatool doc classes" provides a tutorial.
  4221 
  4222 * Generic code generator framework allows to generate executable
  4223 code for ML and Haskell (including Isabelle classes).  A short usage
  4224 sketch:
  4225 
  4226     internal compilation:
  4227         export_code <list of constants (term syntax)> in SML
  4228     writing SML code to a file:
  4229         export_code <list of constants (term syntax)> in SML <filename>
  4230     writing OCaml code to a file:
  4231         export_code <list of constants (term syntax)> in OCaml <filename>
  4232     writing Haskell code to a bunch of files:
  4233         export_code <list of constants (term syntax)> in Haskell <filename>
  4234 
  4235     evaluating closed propositions to True/False using code generation:
  4236         method ``eval''
  4237 
  4238 Reasonable default setup of framework in HOL.
  4239 
  4240 Theorem attributs for selecting and transforming function equations theorems:
  4241 
  4242     [code fun]:        select a theorem as function equation for a specific constant
  4243     [code fun del]:    deselect a theorem as function equation for a specific constant
  4244     [code inline]:     select an equation theorem for unfolding (inlining) in place
  4245     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  4246 
  4247 User-defined serializations (target in {SML, OCaml, Haskell}):
  4248 
  4249     code_const <and-list of constants (term syntax)>
  4250       {(target) <and-list of const target syntax>}+
  4251 
  4252     code_type <and-list of type constructors>
  4253       {(target) <and-list of type target syntax>}+
  4254 
  4255     code_instance <and-list of instances>
  4256       {(target)}+
  4257         where instance ::= <type constructor> :: <class>
  4258 
  4259     code_class <and_list of classes>
  4260       {(target) <and-list of class target syntax>}+
  4261         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4262 
  4263 code_instance and code_class only are effective to target Haskell.
  4264 
  4265 For example usage see src/HOL/ex/Codegenerator.thy and
  4266 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4267 generation from Isabelle/HOL theories is available via "isatool doc
  4268 codegen".
  4269 
  4270 * Code generator: consts in 'consts_code' Isar commands are now
  4271 referred to by usual term syntax (including optional type
  4272 annotations).
  4273 
  4274 * Command 'no_translations' removes translation rules from theory
  4275 syntax.
  4276 
  4277 * Overloaded definitions are now actually checked for acyclic
  4278 dependencies.  The overloading scheme is slightly more general than
  4279 that of Haskell98, although Isabelle does not demand an exact
  4280 correspondence to type class and instance declarations.
  4281 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4282 exotic versions of overloading -- at the discretion of the user!
  4283 
  4284 Polymorphic constants are represented via type arguments, i.e. the
  4285 instantiation that matches an instance against the most general
  4286 declaration given in the signature.  For example, with the declaration
  4287 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4288 as c(nat).  Overloading is essentially simultaneous structural
  4289 recursion over such type arguments.  Incomplete specification patterns
  4290 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4291 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4292 Command 'print_theory' outputs the normalized system of recursive
  4293 equations, see section "definitions".
  4294 
  4295 * Configuration options are maintained within the theory or proof
  4296 context (with name and type bool/int/string), providing a very simple
  4297 interface to a poor-man's version of general context data.  Tools may
  4298 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4299 these values using Config.get etc.  Users may change options via an
  4300 associated attribute of the same name.  This form of context
  4301 declaration works particularly well with commands 'declare' or
  4302 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4303 very easy to avoid global references, which would not observe Isar
  4304 toplevel undo/redo and fail to work with multithreading.
  4305 
  4306 Various global ML references of Pure and HOL have been turned into
  4307 configuration options:
  4308 
  4309   Unify.search_bound		unify_search_bound
  4310   Unify.trace_bound		unify_trace_bound
  4311   Unify.trace_simp		unify_trace_simp
  4312   Unify.trace_types		unify_trace_types
  4313   Simplifier.simp_depth_limit	simp_depth_limit
  4314   Blast.depth_limit		blast_depth_limit
  4315   DatatypeProp.dtK		datatype_distinctness_limit
  4316   fast_arith_neq_limit  	fast_arith_neq_limit
  4317   fast_arith_split_limit	fast_arith_split_limit
  4318 
  4319 * Named collections of theorems may be easily installed as context
  4320 data using the functor NamedThmsFun (see also
  4321 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4322 attributes; there is also a toplevel print command.  This facility is
  4323 just a common case of general context data, which is the preferred way
  4324 for anything more complex than just a list of facts in canonical
  4325 order.
  4326 
  4327 * Isar: command 'declaration' augments a local theory by generic
  4328 declaration functions written in ML.  This enables arbitrary content
  4329 being added to the context, depending on a morphism that tells the
  4330 difference of the original declaration context wrt. the application
  4331 context encountered later on.
  4332 
  4333 * Isar: proper interfaces for simplification procedures.  Command
  4334 'simproc_setup' declares named simprocs (with match patterns, and body
  4335 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4336 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4337 
  4338 * Isar: an extra pair of brackets around attribute declarations
  4339 abbreviates a theorem reference involving an internal dummy fact,
  4340 which will be ignored later --- only the effect of the attribute on
  4341 the background context will persist.  This form of in-place
  4342 declarations is particularly useful with commands like 'declare' and
  4343 'using', for example ``have A using [[simproc a]] by simp''.
  4344 
  4345 * Isar: method "assumption" (and implicit closing of subproofs) now
  4346 takes simple non-atomic goal assumptions into account: after applying
  4347 an assumption as a rule the resulting subgoals are solved by atomic
  4348 assumption steps.  This is particularly useful to finish 'obtain'
  4349 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4350 without referring to the original premise "!!x. P x ==> thesis" in the
  4351 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4352 more permissive.
  4353 
  4354 * Isar: implicit use of prems from the Isar proof context is
  4355 considered a legacy feature.  Common applications like ``have A .''
  4356 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4357 referencing facts explicitly here improves readability and
  4358 maintainability of proof texts.
  4359 
  4360 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4361 the obtained context from the course of reasoning!  For example:
  4362 
  4363   assume "EX x y. A x & B y"   -- "any previous fact"
  4364   then guess x and y by clarify
  4365 
  4366 This technique is potentially adventurous, depending on the facts and
  4367 proof tools being involved here.
  4368 
  4369 * Isar: known facts from the proof context may be specified as literal
  4370 propositions, using ASCII back-quote syntax.  This works wherever
  4371 named facts used to be allowed so far, in proof commands, proof
  4372 methods, attributes etc.  Literal facts are retrieved from the context
  4373 according to unification of type and term parameters.  For example,
  4374 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4375 theorems in the current context, then these are valid literal facts:
  4376 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4377 
  4378 There is also a proof method "fact" which does the same composition
  4379 for explicit goal states, e.g. the following proof texts coincide with
  4380 certain special cases of literal facts:
  4381 
  4382   have "A" by fact                 ==  note `A`
  4383   have "A ==> B" by fact           ==  note `A ==> B`
  4384   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4385   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4386 
  4387 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4388 outer syntax.  Thus symbolic identifiers may be used without
  4389 additional white space in declarations like this: ``assume *: A''.
  4390 
  4391 * Isar: 'print_facts' prints all local facts of the current context,
  4392 both named and unnamed ones.
  4393 
  4394 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4395 
  4396   def x == "t" and y == "u"
  4397 
  4398 * Isar: added command 'unfolding', which is structurally similar to
  4399 'using', but affects both the goal state and facts by unfolding given
  4400 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4401 'unfolded' attribute may be replaced by first-class proof text.
  4402 
  4403 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4404 and command 'unfolding' now all support object-level equalities
  4405 (potentially conditional).  The underlying notion of rewrite rule is
  4406 analogous to the 'rule_format' attribute, but *not* that of the
  4407 Simplifier (which is usually more generous).
  4408 
  4409 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4410 premises of a theorem by n. Useful in conjunction with drule.
  4411 
  4412 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4413 method expression within a sandbox consisting of the first N
  4414 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4415 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4416 simplifies all new goals that emerge from applying rule foo to the
  4417 originally first one.
  4418 
  4419 * Isar: schematic goals are no longer restricted to higher-order
  4420 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4421 expected.
  4422 
  4423 * Isar: the conclusion of a long theorem statement is now either
  4424 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4425 (essentially a disjunction of cases with local parameters and
  4426 assumptions).  The latter allows to express general elimination rules
  4427 adequately; in this notation common elimination rules look like this:
  4428 
  4429   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4430     assumes "EX x. P x"
  4431     obtains x where "P x"
  4432 
  4433   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4434     assumes "A & B"
  4435     obtains A and B
  4436 
  4437   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4438     assumes "A | B"
  4439     obtains
  4440       A
  4441     | B
  4442 
  4443 The subsequent classical rules even refer to the formal "thesis"
  4444 explicitly:
  4445 
  4446   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4447     obtains "~ thesis"
  4448 
  4449   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4450     obtains "thesis ==> something"
  4451 
  4452 The actual proof of an 'obtains' statement is analogous to that of the
  4453 Isar proof element 'obtain', only that there may be several cases.
  4454 Optional case names may be specified in parentheses; these will be
  4455 available both in the present proof and as annotations in the
  4456 resulting rule, for later use with the 'cases' method (cf. attribute
  4457 case_names).
  4458 
  4459 * Isar: the assumptions of a long theorem statement are available as
  4460 "assms" fact in the proof context.  This is more appropriate than the
  4461 (historical) "prems", which refers to all assumptions of the current
  4462 context, including those from the target locale, proof body etc.
  4463 
  4464 * Isar: 'print_statement' prints theorems from the current theory or
  4465 proof context in long statement form, according to the syntax of a
  4466 top-level lemma.
  4467 
  4468 * Isar: 'obtain' takes an optional case name for the local context
  4469 introduction rule (default "that").
  4470 
  4471 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4472 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4473 to occur.
  4474 
  4475 * Pure: syntax "CONST name" produces a fully internalized constant
  4476 according to the current context.  This is particularly useful for
  4477 syntax translations that should refer to internal constant
  4478 representations independently of name spaces.
  4479 
  4480 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4481 instead of "FOO ". This allows multiple binder declarations to coexist
  4482 in the same context.  INCOMPATIBILITY.
  4483 
  4484 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4485 primitive that also works in a locale context (both for constants and
  4486 fixed variables). Type declaration and internal syntactic representation
  4487 of given constants retrieved from the context. Likewise, the
  4488 'no_notation' command allows to remove given syntax annotations from the
  4489 current context.
  4490 
  4491 * Isar/locales: new derived specification elements 'axiomatization',
  4492 'definition', 'abbreviation', which support type-inference, admit
  4493 object-level specifications (equality, equivalence).  See also the
  4494 isar-ref manual.  Examples:
  4495 
  4496   axiomatization
  4497     eq  (infix "===" 50) where
  4498     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4499 
  4500   definition "f x y = x + y + 1"
  4501   definition g where "g x = f x x"
  4502 
  4503   abbreviation
  4504     neq  (infix "=!=" 50) where
  4505     "x =!= y == ~ (x === y)"
  4506 
  4507 These specifications may be also used in a locale context.  Then the
  4508 constants being introduced depend on certain fixed parameters, and the
  4509 constant name is qualified by the locale base name.  An internal
  4510 abbreviation takes care for convenient input and output, making the
  4511 parameters implicit and using the original short name.  See also
  4512 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4513 entities from a monomorphic theory.
  4514 
  4515 Presently, abbreviations are only available 'in' a target locale, but
  4516 not inherited by general import expressions.  Also note that
  4517 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4518 'translations' in common applications.  The "no_abbrevs" print mode
  4519 prevents folding of abbreviations in term output.
  4520 
  4521 Concrete syntax is attached to specified constants in internal form,
  4522 independently of name spaces.  The parse tree representation is
  4523 slightly different -- use 'notation' instead of raw 'syntax', and
  4524 'translations' with explicit "CONST" markup to accommodate this.
  4525 
  4526 * Pure/Isar: unified syntax for new-style specification mechanisms
  4527 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4528 full type inference and dummy patterns ("_").  For example:
  4529 
  4530   definition "K x _ = x"
  4531 
  4532   inductive conj for A B
  4533   where "A ==> B ==> conj A B"
  4534 
  4535 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4536 the current context.  Print mode "no_abbrevs" prevents inversion of
  4537 abbreviations on output.
  4538 
  4539 * Isar/locales: improved parameter handling: use of locales "var" and
  4540 "struct" no longer necessary; - parameter renamings are no longer
  4541 required to be injective.  For example, this allows to define
  4542 endomorphisms as locale endom = homom mult mult h.
  4543 
  4544 * Isar/locales: changed the way locales with predicates are defined.
  4545 Instead of accumulating the specification, the imported expression is
  4546 now an interpretation.  INCOMPATIBILITY: different normal form of
  4547 locale expressions.  In particular, in interpretations of locales with
  4548 predicates, goals repesenting already interpreted fragments are not
  4549 removed automatically.  Use methods `intro_locales' and
  4550 `unfold_locales'; see below.
  4551 
  4552 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4553 provide backward reasoning on locales predicates.  The methods are
  4554 aware of interpretations and discharge corresponding goals.
  4555 `intro_locales' is less aggressive then `unfold_locales' and does not
  4556 unfold predicates to assumptions.
  4557 
  4558 * Isar/locales: the order in which locale fragments are accumulated
  4559 has changed.  This enables to override declarations from fragments due
  4560 to interpretations -- for example, unwanted simp rules.
  4561 
  4562 * Isar/locales: interpretation in theories and proof contexts has been
  4563 extended.  One may now specify (and prove) equations, which are
  4564 unfolded in interpreted theorems.  This is useful for replacing
  4565 defined concepts (constants depending on locale parameters) by
  4566 concepts already existing in the target context.  Example:
  4567 
  4568   interpretation partial_order ["op <= :: [int, int] => bool"]
  4569     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4570 
  4571 Typically, the constant `partial_order.less' is created by a
  4572 definition specification element in the context of locale
  4573 partial_order.
  4574 
  4575 * Method "induct": improved internal context management to support
  4576 local fixes and defines on-the-fly. Thus explicit meta-level
  4577 connectives !!  and ==> are rarely required anymore in inductive goals
  4578 (using object-logic connectives for this purpose has been long
  4579 obsolete anyway). Common proof patterns are explained in
  4580 src/HOL/Induct/Common_Patterns.thy, see also
  4581 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4582 examples.
  4583 
  4584 * Method "induct": improved handling of simultaneous goals. Instead of
  4585 introducing object-level conjunction, the statement is now split into
  4586 several conclusions, while the corresponding symbolic cases are nested
  4587 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4588 see src/HOL/Induct/Common_Patterns.thy, for example.
  4589 
  4590 * Method "induct": mutual induction rules are now specified as a list
  4591 of rule sharing the same induction cases. HOL packages usually provide
  4592 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4593 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4594 mutual induction rules differently, i.e. like this:
  4595 
  4596   (induct rule: foo_bar.inducts)
  4597   (induct set: foo bar)
  4598   (induct pred: foo bar)
  4599   (induct type: foo bar)
  4600 
  4601 The ML function ProjectRule.projections turns old-style rules into the
  4602 new format.
  4603 
  4604 * Method "coinduct": dual of induction, see
  4605 src/HOL/Library/Coinductive_List.thy for various examples.
  4606 
  4607 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4608 considered a legacy feature.
  4609 
  4610 * Attribute "symmetric" produces result with standardized schematic
  4611 variables (index 0).  Potential INCOMPATIBILITY.
  4612 
  4613 * Simplifier: by default the simplifier trace only shows top level
  4614 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4615 default. Thus there is less danger of being flooded by the trace. The
  4616 trace indicates where parts have been suppressed.
  4617   
  4618 * Provers/classical: removed obsolete classical version of elim_format
  4619 attribute; classical elim/dest rules are now treated uniformly when
  4620 manipulating the claset.
  4621 
  4622 * Provers/classical: stricter checks to ensure that supplied intro,
  4623 dest and elim rules are well-formed; dest and elim rules must have at
  4624 least one premise.
  4625 
  4626 * Provers/classical: attributes dest/elim/intro take an optional
  4627 weight argument for the rule (just as the Pure versions).  Weights are
  4628 ignored by automated tools, but determine the search order of single
  4629 rule steps.
  4630 
  4631 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4632 where the body does not mention the bound variable.  Note that dummy
  4633 patterns implicitly depend on their context of bounds, which makes
  4634 "{_. _}" match any set comprehension as expected.  Potential
  4635 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4636 constant "_idtdummy" in the binding position.
  4637 
  4638 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4639 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4640 for example "A -> B" => "Pi A (%_. B)".
  4641 
  4642 * Pure: 'class_deps' command visualizes the subclass relation, using
  4643 the graph browser tool.
  4644 
  4645 * Pure: 'print_theory' now suppresses certain internal declarations by
  4646 default; use '!' option for full details.
  4647 
  4648 
  4649 *** HOL ***
  4650 
  4651 * Method "metis" proves goals by applying the Metis general-purpose
  4652 resolution prover (see also http://gilith.com/software/metis/).
  4653 Examples are in the directory MetisExamples.  WARNING: the
  4654 Isabelle/HOL-Metis integration does not yet work properly with
  4655 multi-threading.
  4656   
  4657 * Command 'sledgehammer' invokes external automatic theorem provers as
  4658 background processes.  It generates calls to the "metis" method if
  4659 successful. These can be pasted into the proof.  Users do not have to
  4660 wait for the automatic provers to return.  WARNING: does not really
  4661 work with multi-threading.
  4662 
  4663 * New "auto_quickcheck" feature tests outermost goal statements for
  4664 potential counter-examples.  Controlled by ML references
  4665 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4666 5000 milliseconds).  Fails silently if statements is outside of
  4667 executable fragment, or any other codgenerator problem occurs.
  4668 
  4669 * New constant "undefined" with axiom "undefined x = undefined".
  4670 
  4671 * Added class "HOL.eq", allowing for code generation with polymorphic
  4672 equality.
  4673 
  4674 * Some renaming of class constants due to canonical name prefixing in
  4675 the new 'class' package:
  4676 
  4677     HOL.abs ~> HOL.abs_class.abs
  4678     HOL.divide ~> HOL.divide_class.divide
  4679     0 ~> HOL.zero_class.zero
  4680     1 ~> HOL.one_class.one
  4681     op + ~> HOL.plus_class.plus
  4682     op - ~> HOL.minus_class.minus
  4683     uminus ~> HOL.minus_class.uminus
  4684     op * ~> HOL.times_class.times
  4685     op < ~> HOL.ord_class.less
  4686     op <= > HOL.ord_class.less_eq
  4687     Nat.power ~> Power.power_class.power
  4688     Nat.size ~> Nat.size_class.size
  4689     Numeral.number_of ~> Numeral.number_class.number_of
  4690     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4691     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4692     Orderings.min ~> Orderings.ord_class.min
  4693     Orderings.max ~> Orderings.ord_class.max
  4694     Divides.op div ~> Divides.div_class.div
  4695     Divides.op mod ~> Divides.div_class.mod
  4696     Divides.op dvd ~> Divides.div_class.dvd
  4697 
  4698 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4699 
  4700 a) User-defined constants using any of the names "plus", "minus",
  4701 "times", "less" or "less_eq". The standard syntax translations for
  4702 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4703 names.
  4704 
  4705 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4706 INCOMPATIBILITY: use more specific names.
  4707 
  4708 c) Permutative equations (e.g. "a + b = b + a")
  4709 Since the change of names also changes the order of terms, permutative
  4710 rewrite rules may get applied in a different order. Experience shows
  4711 that this is rarely the case (only two adaptions in the whole Isabelle
  4712 distribution).  INCOMPATIBILITY: rewrite proofs
  4713 
  4714 d) ML code directly refering to constant names
  4715 This in general only affects hand-written proof tactics, simprocs and
  4716 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4717 Consider using @{const_name} antiquotation.
  4718 
  4719 * New class "default" with associated constant "default".
  4720 
  4721 * Function "sgn" is now overloaded and available on int, real, complex
  4722 (and other numeric types), using class "sgn".  Two possible defs of
  4723 sgn are given as equational assumptions in the classes sgn_if and
  4724 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4725 INCOMPATIBILITY.
  4726 
  4727 * Locale "partial_order" now unified with class "order" (cf. theory
  4728 Orderings), added parameter "less".  INCOMPATIBILITY.
  4729 
  4730 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4731 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4732 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4733 
  4734 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4735 changed order of proof goals in instance proofs.
  4736 
  4737 * The transitivity reasoner for partial and linear orders is set up
  4738 for classes "order" and "linorder".  Instances of the reasoner are available
  4739 in all contexts importing or interpreting the corresponding locales.
  4740 Method "order" invokes the reasoner separately; the reasoner
  4741 is also integrated with the Simplifier as a solver.  Diagnostic
  4742 command 'print_orders' shows the available instances of the reasoner
  4743 in the current context.
  4744 
  4745 * Localized monotonicity predicate in theory "Orderings"; integrated
  4746 lemmas max_of_mono and min_of_mono with this predicate.
  4747 INCOMPATIBILITY.
  4748 
  4749 * Formulation of theorem "dense" changed slightly due to integration
  4750 with new class dense_linear_order.
  4751 
  4752 * Uniform lattice theory development in HOL.
  4753 
  4754     constants "meet" and "join" now named "inf" and "sup"
  4755     constant "Meet" now named "Inf"
  4756 
  4757     classes "meet_semilorder" and "join_semilorder" now named
  4758       "lower_semilattice" and "upper_semilattice"
  4759     class "lorder" now named "lattice"
  4760     class "comp_lat" now named "complete_lattice"
  4761 
  4762     Instantiation of lattice classes allows explicit definitions
  4763     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4764 
  4765   INCOMPATIBILITY.  Theorem renames:
  4766 
  4767     meet_left_le            ~> inf_le1
  4768     meet_right_le           ~> inf_le2
  4769     join_left_le            ~> sup_ge1
  4770     join_right_le           ~> sup_ge2
  4771     meet_join_le            ~> inf_sup_ord
  4772     le_meetI                ~> le_infI
  4773     join_leI                ~> le_supI
  4774     le_meet                 ~> le_inf_iff
  4775     le_join                 ~> ge_sup_conv
  4776     meet_idempotent         ~> inf_idem
  4777     join_idempotent         ~> sup_idem
  4778     meet_comm               ~> inf_commute
  4779     join_comm               ~> sup_commute
  4780     meet_leI1               ~> le_infI1
  4781     meet_leI2               ~> le_infI2
  4782     le_joinI1               ~> le_supI1
  4783     le_joinI2               ~> le_supI2
  4784     meet_assoc              ~> inf_assoc
  4785     join_assoc              ~> sup_assoc
  4786     meet_left_comm          ~> inf_left_commute
  4787     meet_left_idempotent    ~> inf_left_idem
  4788     join_left_comm          ~> sup_left_commute
  4789     join_left_idempotent    ~> sup_left_idem
  4790     meet_aci                ~> inf_aci
  4791     join_aci                ~> sup_aci
  4792     le_def_meet             ~> le_iff_inf
  4793     le_def_join             ~> le_iff_sup
  4794     join_absorp2            ~> sup_absorb2
  4795     join_absorp1            ~> sup_absorb1
  4796     meet_absorp1            ~> inf_absorb1
  4797     meet_absorp2            ~> inf_absorb2
  4798     meet_join_absorp        ~> inf_sup_absorb
  4799     join_meet_absorp        ~> sup_inf_absorb
  4800     distrib_join_le         ~> distrib_sup_le
  4801     distrib_meet_le         ~> distrib_inf_le
  4802 
  4803     add_meet_distrib_left   ~> add_inf_distrib_left
  4804     add_join_distrib_left   ~> add_sup_distrib_left
  4805     is_join_neg_meet        ~> is_join_neg_inf
  4806     is_meet_neg_join        ~> is_meet_neg_sup
  4807     add_meet_distrib_right  ~> add_inf_distrib_right
  4808     add_join_distrib_right  ~> add_sup_distrib_right
  4809     add_meet_join_distribs  ~> add_sup_inf_distribs
  4810     join_eq_neg_meet        ~> sup_eq_neg_inf
  4811     meet_eq_neg_join        ~> inf_eq_neg_sup
  4812     add_eq_meet_join        ~> add_eq_inf_sup
  4813     meet_0_imp_0            ~> inf_0_imp_0
  4814     join_0_imp_0            ~> sup_0_imp_0
  4815     meet_0_eq_0             ~> inf_0_eq_0
  4816     join_0_eq_0             ~> sup_0_eq_0
  4817     neg_meet_eq_join        ~> neg_inf_eq_sup
  4818     neg_join_eq_meet        ~> neg_sup_eq_inf
  4819     join_eq_if              ~> sup_eq_if
  4820 
  4821     mono_meet               ~> mono_inf
  4822     mono_join               ~> mono_sup
  4823     meet_bool_eq            ~> inf_bool_eq
  4824     join_bool_eq            ~> sup_bool_eq
  4825     meet_fun_eq             ~> inf_fun_eq
  4826     join_fun_eq             ~> sup_fun_eq
  4827     meet_set_eq             ~> inf_set_eq
  4828     join_set_eq             ~> sup_set_eq
  4829     meet1_iff               ~> inf1_iff
  4830     meet2_iff               ~> inf2_iff
  4831     meet1I                  ~> inf1I
  4832     meet2I                  ~> inf2I
  4833     meet1D1                 ~> inf1D1
  4834     meet2D1                 ~> inf2D1
  4835     meet1D2                 ~> inf1D2
  4836     meet2D2                 ~> inf2D2
  4837     meet1E                  ~> inf1E
  4838     meet2E                  ~> inf2E
  4839     join1_iff               ~> sup1_iff
  4840     join2_iff               ~> sup2_iff
  4841     join1I1                 ~> sup1I1
  4842     join2I1                 ~> sup2I1
  4843     join1I1                 ~> sup1I1
  4844     join2I2                 ~> sup1I2
  4845     join1CI                 ~> sup1CI
  4846     join2CI                 ~> sup2CI
  4847     join1E                  ~> sup1E
  4848     join2E                  ~> sup2E
  4849 
  4850     is_meet_Meet            ~> is_meet_Inf
  4851     Meet_bool_def           ~> Inf_bool_def
  4852     Meet_fun_def            ~> Inf_fun_def
  4853     Meet_greatest           ~> Inf_greatest
  4854     Meet_lower              ~> Inf_lower
  4855     Meet_set_def            ~> Inf_set_def
  4856 
  4857     Sup_def                 ~> Sup_Inf
  4858     Sup_bool_eq             ~> Sup_bool_def
  4859     Sup_fun_eq              ~> Sup_fun_def
  4860     Sup_set_eq              ~> Sup_set_def
  4861 
  4862     listsp_meetI            ~> listsp_infI
  4863     listsp_meet_eq          ~> listsp_inf_eq
  4864 
  4865     meet_min                ~> inf_min
  4866     join_max                ~> sup_max
  4867 
  4868 * Added syntactic class "size"; overloaded constant "size" now has
  4869 type "'a::size ==> bool"
  4870 
  4871 * Internal reorganisation of `size' of datatypes: size theorems
  4872 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4873 simplification rules by default!); theorems "prod.size" now named
  4874 "*.size".
  4875 
  4876 * Class "div" now inherits from class "times" rather than "type".
  4877 INCOMPATIBILITY.
  4878 
  4879 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4880 Linorder etc.  have disappeared; operations defined in terms of
  4881 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4882 
  4883 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4884 
  4885 * HOL-Word: New extensive library and type for generic, fixed size
  4886 machine words, with arithmetic, bit-wise, shifting and rotating
  4887 operations, reflection into int, nat, and bool lists, automation for
  4888 linear arithmetic (by automatic reflection into nat or int), including
  4889 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4890 arithmetic type classes, supporting automatic simplification of
  4891 numerals on all operations.
  4892 
  4893 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4894 
  4895 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4896 
  4897 * Code generator library theories:
  4898   - Code_Integer represents HOL integers by big integer literals in target
  4899     languages.
  4900   - Code_Char represents HOL characters by character literals in target
  4901     languages.
  4902   - Code_Char_chr like Code_Char, but also offers treatment of character
  4903     codes; includes Code_Integer.
  4904   - Executable_Set allows to generate code for finite sets using lists.
  4905   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4906     denominator).
  4907   - Executable_Real implements a subset of real numbers, namly those
  4908     representable by rational numbers.
  4909   - Efficient_Nat implements natural numbers by integers, which in general will
  4910     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4911     includes Code_Integer.
  4912   - Code_Index provides an additional datatype index which is mapped to
  4913     target-language built-in integers.
  4914   - Code_Message provides an additional datatype message_string which is isomorphic to
  4915     strings; messages are mapped to target-language strings.
  4916 
  4917 * New package for inductive predicates
  4918 
  4919   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4920 
  4921     inductive
  4922       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4923       for z_1 :: U_1 and ... and z_n :: U_m
  4924     where
  4925       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4926     | ...
  4927 
  4928   with full support for type-inference, rather than
  4929 
  4930     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4931 
  4932     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4933     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4934 
  4935     inductive "s z_1 ... z_m"
  4936     intros
  4937       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4938       ...
  4939 
  4940   For backward compatibility, there is a wrapper allowing inductive
  4941   sets to be defined with the new package via
  4942 
  4943     inductive_set
  4944       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4945       for z_1 :: U_1 and ... and z_n :: U_m
  4946     where
  4947       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4948     | ...
  4949 
  4950   or
  4951 
  4952     inductive_set
  4953       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4954       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4955       for z_1 :: U_1 and ... and z_n :: U_m
  4956     where
  4957       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4958     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4959     | ...
  4960 
  4961   if the additional syntax "p ..." is required.
  4962 
  4963   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4964   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4965 
  4966   INCOMPATIBILITIES:
  4967 
  4968   - Since declaration and definition of inductive sets or predicates
  4969     is no longer separated, abbreviations involving the newly
  4970     introduced sets or predicates must be specified together with the
  4971     introduction rules after the 'where' keyword (see above), rather
  4972     than before the actual inductive definition.
  4973 
  4974   - The variables in induction and elimination rules are now
  4975     quantified in the order of their occurrence in the introduction
  4976     rules, rather than in alphabetical order. Since this may break
  4977     some proofs, these proofs either have to be repaired, e.g. by
  4978     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4979     statements of the form
  4980 
  4981       case (rule_i a_i_1 ... a_i_{k_i})
  4982 
  4983     or the old order of quantification has to be restored by explicitly adding
  4984     meta-level quantifiers in the introduction rules, i.e.
  4985 
  4986       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4987 
  4988   - The format of the elimination rules is now
  4989 
  4990       p z_1 ... z_m x_1 ... x_n ==>
  4991         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4992         ==> ... ==> P
  4993 
  4994     for predicates and
  4995 
  4996       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4997         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4998         ==> ... ==> P
  4999 
  5000     for sets rather than
  5001 
  5002       x : s z_1 ... z_m ==>
  5003         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  5004         ==> ... ==> P
  5005 
  5006     This may require terms in goals to be expanded to n-tuples
  5007     (e.g. using case_tac or simplification with the split_paired_all
  5008     rule) before the above elimination rule is applicable.
  5009 
  5010   - The elimination or case analysis rules for (mutually) inductive
  5011     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  5012     list of rules "p_1_..._p_k.elims" is no longer available.
  5013 
  5014 * New package "function"/"fun" for general recursive functions,
  5015 supporting mutual and nested recursion, definitions in local contexts,
  5016 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  5017 for small examples, and the separate tutorial on the function
  5018 package. The old recdef "package" is still available as before, but
  5019 users are encouraged to use the new package.
  5020 
  5021 * Method "lexicographic_order" automatically synthesizes termination
  5022 relations as lexicographic combinations of size measures. 
  5023 
  5024 * Case-expressions allow arbitrary constructor-patterns (including
  5025 "_") and take their order into account, like in functional
  5026 programming.  Internally, this is translated into nested
  5027 case-expressions; missing cases are added and mapped to the predefined
  5028 constant "undefined". In complicated cases printing may no longer show
  5029 the original input but the internal form. Lambda-abstractions allow
  5030 the same form of pattern matching: "% pat1 => e1 | ..." is an
  5031 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  5032 variable.
  5033 
  5034 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  5035 is an abbreviation for "of_nat :: nat => int". The simplification
  5036 rules for "of_nat" have been changed to work like "int" did
  5037 previously.  Potential INCOMPATIBILITY:
  5038   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  5039   - of_nat_diff and of_nat_mult are no longer default simp rules
  5040 
  5041 * Method "algebra" solves polynomial equations over (semi)rings using
  5042 Groebner bases. The (semi)ring structure is defined by locales and the
  5043 tool setup depends on that generic context. Installing the method for
  5044 a specific type involves instantiating the locale and possibly adding
  5045 declarations for computation on the coefficients.  The method is
  5046 already instantiated for natural numbers and for the axiomatic class
  5047 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  5048 CALCULEMUS 2007 for the general principles underlying this
  5049 architecture of context-aware proof-tools.
  5050 
  5051 * Method "ferrack" implements quantifier elimination over
  5052 special-purpose dense linear orders using locales (analogous to
  5053 "algebra"). The method is already installed for class
  5054 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  5055 rat, etc.
  5056 
  5057 * Former constant "List.op @" now named "List.append".  Use ML
  5058 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  5059 circumvent possible incompatibilities when working on ML level.
  5060 
  5061 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  5062 
  5063 * New function listsum :: 'a list => 'a for arbitrary monoids.
  5064 Special syntax: "SUM x <- xs. f x" (and latex variants)
  5065 
  5066 * New syntax for Haskell-like list comprehension (input only), eg.
  5067 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  5068 
  5069 * The special syntax for function "filter" has changed from [x :
  5070 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  5071 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  5072 
  5073 * [a..b] is now defined for arbitrary linear orders.  It used to be
  5074 defined on nat only, as an abbreviation for [a..<Suc b]
  5075 INCOMPATIBILITY.
  5076 
  5077 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  5078 
  5079 * New functions "sorted" and "sort" in src/HOL/List.thy.
  5080 
  5081 * New lemma collection field_simps (an extension of ring_simps) for
  5082 manipulating (in)equations involving division. Multiplies with all
  5083 denominators that can be proved to be non-zero (in equations) or
  5084 positive/negative (in inequations).
  5085 
  5086 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  5087 have been improved and renamed to ring_simps, group_simps and
  5088 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  5089 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  5090 
  5091 * Theory Library/Commutative_Ring: switched from recdef to function
  5092 package; constants add, mul, pow now curried.  Infix syntax for
  5093 algebraic operations.
  5094 
  5095 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  5096 INCOMPATIBILITY.
  5097 
  5098 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  5099 INCOMPATIBILITY.
  5100 
  5101 * HOL/records: generalised field-update to take a function on the
  5102 field rather than the new value: r(|A := x|) is translated to A_update
  5103 (K x) r The K-combinator that is internally used is called K_record.
  5104 INCOMPATIBILITY: Usage of the plain update functions has to be
  5105 adapted.
  5106  
  5107 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  5108 * x = 0, which are required for a semiring.  Richer structures do not
  5109 inherit from semiring_0 anymore, because this property is a theorem
  5110 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  5111 there is more to prove, but this is mostly trivial.
  5112 
  5113 * Class "recpower" is generalized to arbitrary monoids, not just
  5114 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  5115 commutativity or semiring properties additionally.
  5116 
  5117 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  5118 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  5119 better use 'abbreviation'.
  5120 
  5121 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  5122 
  5123 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  5124 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  5125 significant changes for setting up numeral syntax for types:
  5126   - New constants Numeral.pred and Numeral.succ instead
  5127       of former Numeral.bin_pred and Numeral.bin_succ.
  5128   - Use integer operations instead of bin_add, bin_mult and so on.
  5129   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  5130   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  5131 
  5132 See src/HOL/Integ/IntArith.thy for an example setup.
  5133 
  5134 * Command 'normal_form' computes the normal form of a term that may
  5135 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  5136 produces ``[b, c, a]'' (without proof).  This command is suitable for
  5137 heavy-duty computations because the functions are compiled to ML
  5138 first.  Correspondingly, a method "normalization" is provided.  See
  5139 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  5140 
  5141 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  5142 25 like -->); output depends on the "iff" print_mode, the default is
  5143 "A = B" (with priority 50).
  5144 
  5145 * Relations less (<) and less_eq (<=) are also available on type bool.
  5146 Modified syntax to disallow nesting without explicit parentheses,
  5147 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  5148 INCOMPATIBILITY.
  5149 
  5150 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  5151 
  5152 * Relation composition operator "op O" now has precedence 75 and binds
  5153 stronger than union and intersection. INCOMPATIBILITY.
  5154 
  5155 * The old set interval syntax "{m..n(}" (and relatives) has been
  5156 removed.  Use "{m..<n}" (and relatives) instead.
  5157 
  5158 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  5159 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  5160 ``declare [[simproc del: neq]]''.
  5161 
  5162 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  5163 True/False.
  5164 
  5165 * Theorem Cons_eq_map_conv no longer declared as "simp".
  5166 
  5167 * Theorem setsum_mult renamed to setsum_right_distrib.
  5168 
  5169 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  5170 ``rule'' method.
  5171 
  5172 * Reimplemented methods "sat" and "satx", with several improvements:
  5173 goals no longer need to be stated as "<prems> ==> False", equivalences
  5174 (i.e. "=" on type bool) are handled, variable names of the form
  5175 "lit_<n>" are no longer reserved, significant speedup.
  5176 
  5177 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  5178 zChaff is still supported as well.
  5179 
  5180 * 'inductive' and 'datatype': provide projections of mutual rules,
  5181 bundled as foo_bar.inducts;
  5182 
  5183 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  5184 Library.
  5185 
  5186 * Library: moved theory Accessible_Part to main HOL.
  5187 
  5188 * Library: added theory Coinductive_List of potentially infinite lists
  5189 as greatest fixed-point.
  5190 
  5191 * Library: added theory AssocList which implements (finite) maps as
  5192 association lists.
  5193 
  5194 * Method "evaluation" solves goals (i.e. a boolean expression)
  5195 efficiently by compiling it to ML.  The goal is "proved" (via an
  5196 oracle) if it evaluates to True.
  5197 
  5198 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  5199 also when invoked by the simplifier.  This results in the Simplifier
  5200 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  5201 Configuration option fast_arith_split_limit=0 recovers the old
  5202 behavior.
  5203 
  5204 * Support for hex (0x20) and binary (0b1001) numerals.
  5205 
  5206 * New method: reify eqs (t), where eqs are equations for an
  5207 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  5208 parameter, computes a term s::'b and a list xs::'a list and proves the
  5209 theorem I xs s = t. This is also known as reification or quoting. The
  5210 resulting theorem is applied to the subgoal to substitute t with I xs
  5211 s.  If t is omitted, the subgoal itself is reified.
  5212 
  5213 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  5214 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  5215 where f is supposed to be a computable function (in the sense of code
  5216 generattion). The method uses reify to compute s and xs as above then
  5217 applies corr_thm and uses normalization by evaluation to "prove" f s =
  5218 r and finally gets the theorem t = r, which is again applied to the
  5219 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  5220 
  5221 * Reflection: Automatic reification now handels binding, an example is
  5222 available in src/HOL/ex/ReflectionEx.thy
  5223 
  5224 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  5225 command 'statespace' that is similar to 'record', but introduces an
  5226 abstract specification based on the locale infrastructure instead of
  5227 HOL types.  This leads to extra flexibility in composing state spaces,
  5228 in particular multiple inheritance and renaming of components.
  5229 
  5230 
  5231 *** HOL-Complex ***
  5232 
  5233 * Hyperreal: Functions root and sqrt are now defined on negative real
  5234 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  5235 Nonnegativity side conditions have been removed from many lemmas, so
  5236 that more subgoals may now be solved by simplification; potential
  5237 INCOMPATIBILITY.
  5238 
  5239 * Real: new type classes formalize real normed vector spaces and
  5240 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  5241 and norm :: 'a => real.
  5242 
  5243 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  5244 reals into other types. The overloaded constant Reals :: 'a set is now
  5245 defined as range of_real; potential INCOMPATIBILITY.
  5246 
  5247 * Real: proper support for ML code generation, including 'quickcheck'.
  5248 Reals are implemented as arbitrary precision rationals.
  5249 
  5250 * Hyperreal: Several constants that previously worked only for the
  5251 reals have been generalized, so they now work over arbitrary vector
  5252 spaces. Type annotations may need to be added in some cases; potential
  5253 INCOMPATIBILITY.
  5254 
  5255   Infinitesimal  :: ('a::real_normed_vector) star set
  5256   HFinite        :: ('a::real_normed_vector) star set
  5257   HInfinite      :: ('a::real_normed_vector) star set
  5258   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5259   monad          :: ('a::real_normed_vector) star => 'a star set
  5260   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5261   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5262   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5263   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5264   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5265   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5266   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5267   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5268   sgn            :: 'a::real_normed_vector => 'a
  5269   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5270 
  5271 * Complex: Some complex-specific constants are now abbreviations for
  5272 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5273 hnorm.  Other constants have been entirely removed in favor of the
  5274 polymorphic versions (INCOMPATIBILITY):
  5275 
  5276   approx        <-- capprox
  5277   HFinite       <-- CFinite
  5278   HInfinite     <-- CInfinite
  5279   Infinitesimal <-- CInfinitesimal
  5280   monad         <-- cmonad
  5281   galaxy        <-- cgalaxy
  5282   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5283   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5284   (ns)deriv     <-- (ns)cderiv
  5285 
  5286 
  5287 *** HOL-Algebra ***
  5288 
  5289 * Formalisation of ideals and the quotient construction over rings.
  5290 
  5291 * Order and lattice theory no longer based on records.
  5292 INCOMPATIBILITY.
  5293 
  5294 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5295 greatest_closed.  INCOMPATIBILITY.
  5296 
  5297 * Method algebra is now set up via an attribute.  For examples see
  5298 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5299 of algebraic structures.
  5300 
  5301 * Renamed theory CRing to Ring.
  5302 
  5303 
  5304 *** HOL-Nominal ***
  5305 
  5306 * Substantial, yet incomplete support for nominal datatypes (binding
  5307 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5308 src/HOL/Nominal/Examples.  Prospective users should consult
  5309 http://isabelle.in.tum.de/nominal/
  5310 
  5311 
  5312 *** ML ***
  5313 
  5314 * ML basics: just one true type int, which coincides with IntInf.int
  5315 (even on SML/NJ).
  5316 
  5317 * ML within Isar: antiquotations allow to embed statically-checked
  5318 formal entities in the source, referring to the context available at
  5319 compile-time.  For example:
  5320 
  5321 ML {* @{sort "{zero,one}"} *}
  5322 ML {* @{typ "'a => 'b"} *}
  5323 ML {* @{term "%x. x"} *}
  5324 ML {* @{prop "x == y"} *}
  5325 ML {* @{ctyp "'a => 'b"} *}
  5326 ML {* @{cterm "%x. x"} *}
  5327 ML {* @{cprop "x == y"} *}
  5328 ML {* @{thm asm_rl} *}
  5329 ML {* @{thms asm_rl} *}
  5330 ML {* @{type_name c} *}
  5331 ML {* @{type_syntax c} *}
  5332 ML {* @{const_name c} *}
  5333 ML {* @{const_syntax c} *}
  5334 ML {* @{context} *}
  5335 ML {* @{theory} *}
  5336 ML {* @{theory Pure} *}
  5337 ML {* @{theory_ref} *}
  5338 ML {* @{theory_ref Pure} *}
  5339 ML {* @{simpset} *}
  5340 ML {* @{claset} *}
  5341 ML {* @{clasimpset} *}
  5342 
  5343 The same works for sources being ``used'' within an Isar context.
  5344 
  5345 * ML in Isar: improved error reporting; extra verbosity with
  5346 ML_Context.trace enabled.
  5347 
  5348 * Pure/General/table.ML: the join operations now works via exceptions
  5349 DUP/SAME instead of type option. This is simpler in simple cases, and
  5350 admits slightly more efficient complex applications.
  5351 
  5352 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5353 use Context.generic instead of just theory.
  5354 
  5355 * Pure: datatype Context.generic joins theory/Proof.context and
  5356 provides some facilities for code that works in either kind of
  5357 context, notably GenericDataFun for uniform theory and proof data.
  5358 
  5359 * Pure: simplified internal attribute type, which is now always
  5360 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5361 local (Proof.context) attributes have been discontinued, while
  5362 minimizing code duplication. Thm.rule_attribute and
  5363 Thm.declaration_attribute build canonical attributes; see also structure
  5364 Context for further operations on Context.generic, notably
  5365 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5366 declarations and definitions.
  5367 
  5368 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5369 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5370 init only required for impure data. INCOMPATIBILITY: empty really need
  5371 to be empty (no dependencies on theory content!)
  5372 
  5373 * Pure/kernel: consts certification ignores sort constraints given in
  5374 signature declarations. (This information is not relevant to the
  5375 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5376 potential INCOMPATIBILITY.
  5377 
  5378 * Pure: axiomatic type classes are now purely definitional, with
  5379 explicit proofs of class axioms and super class relations performed
  5380 internally. See Pure/axclass.ML for the main internal interfaces --
  5381 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5382 AxClass.axiomatize_class/classrel/arity supersede
  5383 Sign.add_classes/classrel/arities.
  5384 
  5385 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5386 global/local versions on theory vs. Proof.context have been
  5387 discontinued; Attrib.syntax and Method.syntax have been adapted
  5388 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5389 attributes, methods, etc.
  5390 
  5391 * Pure: several functions of signature "... -> theory -> theory * ..."
  5392 have been reoriented to "... -> theory -> ... * theory" in order to
  5393 allow natural usage in combination with the ||>, ||>>, |-> and
  5394 fold_map combinators.
  5395 
  5396 * Pure: official theorem names (closed derivations) and additional
  5397 comments (tags) are now strictly separate.  Name hints -- which are
  5398 maintained as tags -- may be attached any time without affecting the
  5399 derivation.
  5400 
  5401 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5402 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5403 achieve the old behaviour.
  5404 
  5405 * Pure: the "Goal" constant is now called "prop", supporting a
  5406 slightly more general idea of ``protecting'' meta-level rule
  5407 statements.
  5408 
  5409 * Pure: Logic.(un)varify only works in a global context, which is now
  5410 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5411 Logic.legacy_(un)varify as temporary workaround.
  5412 
  5413 * Pure: structure Name provides scalable operations for generating
  5414 internal variable names, notably Name.variants etc.  This replaces
  5415 some popular functions from term.ML:
  5416 
  5417   Term.variant		->  Name.variant
  5418   Term.variantlist	->  Name.variant_list
  5419   Term.invent_names	->  Name.invent_list
  5420 
  5421 Note that low-level renaming rarely occurs in new code -- operations
  5422 from structure Variable are used instead (see below).
  5423 
  5424 * Pure: structure Variable provides fundamental operations for proper
  5425 treatment of fixed/schematic variables in a context.  For example,
  5426 Variable.import introduces fixes for schematics of given facts and
  5427 Variable.export reverses the effect (up to renaming) -- this replaces
  5428 various freeze_thaw operations.
  5429 
  5430 * Pure: structure Goal provides simple interfaces for
  5431 init/conclude/finish and tactical prove operations (replacing former
  5432 Tactic.prove).  Goal.prove is the canonical way to prove results
  5433 within a given context; Goal.prove_global is a degraded version for
  5434 theory level goals, including a global Drule.standard.  Note that
  5435 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5436 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5437 in a locale context).
  5438 
  5439 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5440 and type checking (Syntax.check_term etc.), with common combinations
  5441 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5442 which are considered legacy and await removal.
  5443 
  5444 * Pure/Syntax: generic interfaces for type unchecking
  5445 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5446 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5447 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5448 available for convenience, but refer to the very same operations using
  5449 a mere theory instead of a full context.
  5450 
  5451 * Isar: simplified treatment of user-level errors, using exception
  5452 ERROR of string uniformly.  Function error now merely raises ERROR,
  5453 without any side effect on output channels.  The Isar toplevel takes
  5454 care of proper display of ERROR exceptions.  ML code may use plain
  5455 handle/can/try; cat_error may be used to concatenate errors like this:
  5456 
  5457   ... handle ERROR msg => cat_error msg "..."
  5458 
  5459 Toplevel ML code (run directly or through the Isar toplevel) may be
  5460 embedded into the Isar toplevel with exception display/debug like
  5461 this:
  5462 
  5463   Isar.toplevel (fn () => ...)
  5464 
  5465 INCOMPATIBILITY, removed special transform_error facilities, removed
  5466 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5467 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5468 -- use plain ERROR instead.
  5469 
  5470 * Isar: theory setup now has type (theory -> theory), instead of a
  5471 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5472 
  5473 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5474 ProofContext.debug/verbose flags.
  5475 
  5476 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5477 theory before entering a proof state.  Transactions now always see a
  5478 quasi-functional intermediate checkpoint, both in interactive and
  5479 batch mode.
  5480 
  5481 * Isar: simplified interfaces for outer syntax.  Renamed
  5482 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5483 OuterSyntax.add_parsers -- this functionality is now included in
  5484 OuterSyntax.command etc.  INCOMPATIBILITY.
  5485 
  5486 * Simplifier: the simpset of a running simplification process now
  5487 contains a proof context (cf. Simplifier.the_context), which is the
  5488 very context that the initial simpset has been retrieved from (by
  5489 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5490 (solver, looper etc.) may depend on arbitrary proof data.
  5491 
  5492 * Simplifier.inherit_context inherits the proof context (plus the
  5493 local bounds) of the current simplification process; any simproc
  5494 etc. that calls the Simplifier recursively should do this!  Removed
  5495 former Simplifier.inherit_bounds, which is already included here --
  5496 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5497 specify an explicit context using Simplifier.context/theory_context.
  5498 
  5499 * Simplifier/Classical Reasoner: more abstract interfaces
  5500 change_simpset/claset for modifying the simpset/claset reference of a
  5501 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5502 INCOMPATIBILITY.
  5503 
  5504 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5505 "Trueprop" etc.
  5506 
  5507 
  5508 *** System ***
  5509 
  5510 * settings: the default heap location within ISABELLE_HOME_USER now
  5511 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5512 Isabelle installations.
  5513 
  5514 * isabelle-process: option -S (secure mode) disables some critical
  5515 operations, notably runtime compilation and evaluation of ML source
  5516 code.
  5517 
  5518 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5519 
  5520 * Support for parallel execution, using native multicore support of
  5521 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5522 independent theories, according to the given theory header
  5523 specifications. The maximum number of worker threads is specified via
  5524 usedir option -M or the "max-threads" setting in Proof General. A
  5525 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5526 to 6 on a 8-core machine.  User-code needs to observe certain
  5527 guidelines for thread-safe programming, see appendix A in the Isar
  5528 Implementation manual.
  5529 
  5530 
  5531 
  5532 New in Isabelle2005 (October 2005)
  5533 ----------------------------------
  5534 
  5535 *** General ***
  5536 
  5537 * Theory headers: the new header syntax for Isar theories is
  5538 
  5539   theory <name>
  5540   imports <theory1> ... <theoryN>
  5541   uses <file1> ... <fileM>
  5542   begin
  5543 
  5544 where the 'uses' part is optional.  The previous syntax
  5545 
  5546   theory <name> = <theory1> + ... + <theoryN>:
  5547 
  5548 will disappear in the next release.  Use isatool fixheaders to convert
  5549 existing theory files.  Note that there is no change in ancient
  5550 non-Isar theories now, but these will disappear soon.
  5551 
  5552 * Theory loader: parent theories can now also be referred to via
  5553 relative and absolute paths.
  5554 
  5555 * Command 'find_theorems' searches for a list of criteria instead of a
  5556 list of constants. Known criteria are: intro, elim, dest, name:string,
  5557 simp:term, and any term. Criteria can be preceded by '-' to select
  5558 theorems that do not match. Intro, elim, dest select theorems that
  5559 match the current goal, name:s selects theorems whose fully qualified
  5560 name contain s, and simp:term selects all simplification rules whose
  5561 lhs match term.  Any other term is interpreted as pattern and selects
  5562 all theorems matching the pattern. Available in ProofGeneral under
  5563 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5564 
  5565   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5566 
  5567 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5568 matching the current goal as introduction rule and not having "HOL."
  5569 in their name (i.e. not being defined in theory HOL).
  5570 
  5571 * Command 'thms_containing' has been discontinued in favour of
  5572 'find_theorems'; INCOMPATIBILITY.
  5573 
  5574 * Communication with Proof General is now 8bit clean, which means that
  5575 Unicode text in UTF-8 encoding may be used within theory texts (both
  5576 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5577 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5578 
  5579   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5580   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5581 
  5582 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5583 Classical Reasoner.  Typical big applications run around 2 times
  5584 faster.
  5585 
  5586 
  5587 *** Document preparation ***
  5588 
  5589 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5590 of raw sources.  Only those symbols that do not require additional
  5591 LaTeX packages (depending on comments in isabellesym.sty) are
  5592 displayed properly, everything else is left verbatim.  isatool display
  5593 and isatool print are used as front ends (these are subject to the
  5594 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5595 
  5596 * Command tags control specific markup of certain regions of text,
  5597 notably folding and hiding.  Predefined tags include "theory" (for
  5598 theory begin and end), "proof" for proof commands, and "ML" for
  5599 commands involving ML code; the additional tags "visible" and
  5600 "invisible" are unused by default.  Users may give explicit tag
  5601 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5602 interpretation of tags is determined by the LaTeX job during document
  5603 preparation: see option -V of isatool usedir, or options -n and -t of
  5604 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5605 \isadroptag.
  5606 
  5607 Several document versions may be produced at the same time via isatool
  5608 usedir (the generated index.html will link all of them).  Typical
  5609 specifications include ''-V document=theory,proof,ML'' to present
  5610 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5611 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5612 these parts without any formal replacement text.  The Isabelle site
  5613 default settings produce ''document'' and ''outline'' versions as
  5614 specified above.
  5615 
  5616 * Several new antiquotations:
  5617 
  5618   @{term_type term} prints a term with its type annotated;
  5619 
  5620   @{typeof term} prints the type of a term;
  5621 
  5622   @{const const} is the same as @{term const}, but checks that the
  5623   argument is a known logical constant;
  5624 
  5625   @{term_style style term} and @{thm_style style thm} print a term or
  5626   theorem applying a "style" to it
  5627 
  5628   @{ML text}
  5629 
  5630 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5631 definitions, equations, inequations etc., 'concl' printing only the
  5632 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5633 to print the specified premise.  TermStyle.add_style provides an ML
  5634 interface for introducing further styles.  See also the "LaTeX Sugar"
  5635 document practical applications.  The ML antiquotation prints
  5636 type-checked ML expressions verbatim.
  5637 
  5638 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5639 and 'text' support optional locale specification '(in loc)', which
  5640 specifies the default context for interpreting antiquotations.  For
  5641 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5642 
  5643 * Option 'locale=NAME' of antiquotations specifies an alternative
  5644 context interpreting the subsequent argument.  For example: @{thm
  5645 [locale=lattice] inf_assoc}.
  5646 
  5647 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5648 a proof context.
  5649 
  5650 * Proper output of antiquotations for theory commands involving a
  5651 proof context (such as 'locale' or 'theorem (in loc) ...').
  5652 
  5653 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5654 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5655 
  5656 * isatool usedir: new option -C (default true) controls whether option
  5657 -D should include a copy of the original document directory; -C false
  5658 prevents unwanted effects such as copying of administrative CVS data.
  5659 
  5660 
  5661 *** Pure ***
  5662 
  5663 * Considerably improved version of 'constdefs' command.  Now performs
  5664 automatic type-inference of declared constants; additional support for
  5665 local structure declarations (cf. locales and HOL records), see also
  5666 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5667 sequential dependencies of definitions within a single 'constdefs'
  5668 section; moreover, the declared name needs to be an identifier.  If
  5669 all fails, consider to fall back on 'consts' and 'defs' separately.
  5670 
  5671 * Improved indexed syntax and implicit structures.  First of all,
  5672 indexed syntax provides a notational device for subscripted
  5673 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5674 expressions.  Secondly, in a local context with structure
  5675 declarations, number indexes \<^sub>n or the empty index (default
  5676 number 1) refer to a certain fixed variable implicitly; option
  5677 show_structs controls printing of implicit structures.  Typical
  5678 applications of these concepts involve record types and locales.
  5679 
  5680 * New command 'no_syntax' removes grammar declarations (and
  5681 translations) resulting from the given syntax specification, which is
  5682 interpreted in the same manner as for the 'syntax' command.
  5683 
  5684 * 'Advanced' translation functions (parse_translation etc.) may depend
  5685 on the signature of the theory context being presently used for
  5686 parsing/printing, see also isar-ref manual.
  5687 
  5688 * Improved 'oracle' command provides a type-safe interface to turn an
  5689 ML expression of type theory -> T -> term into a primitive rule of
  5690 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5691 is already included here); see also FOL/ex/IffExample.thy;
  5692 INCOMPATIBILITY.
  5693 
  5694 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5695 before); "cI" is no longer bound, use "c.intro" instead.
  5696 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5697 axclasses vs. locales.
  5698 
  5699 * Improved internal renaming of symbolic identifiers -- attach primes
  5700 instead of base 26 numbers.
  5701 
  5702 * New flag show_question_marks controls printing of leading question
  5703 marks in schematic variable names.
  5704 
  5705 * In schematic variable names, *any* symbol following \<^isub> or
  5706 \<^isup> is now treated as part of the base name.  For example, the
  5707 following works without printing of awkward ".0" indexes:
  5708 
  5709   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5710     by simp
  5711 
  5712 * Inner syntax includes (*(*nested*) comments*).
  5713 
  5714 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5715 annotations as "(00...)".
  5716 
  5717 * Clear separation of logical types and nonterminals, where the latter
  5718 may only occur in 'syntax' specifications or type abbreviations.
  5719 Before that distinction was only partially implemented via type class
  5720 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5721 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5722 exotic syntax specifications may require further adaption
  5723 (e.g. Cube/Cube.thy).
  5724 
  5725 * Removed obsolete type class "logic", use the top sort {} instead.
  5726 Note that non-logical types should be declared as 'nonterminals'
  5727 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5728 specifications.
  5729 
  5730 * Attributes 'induct' and 'cases': type or set names may now be
  5731 locally fixed variables as well.
  5732 
  5733 * Simplifier: can now control the depth to which conditional rewriting
  5734 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5735 Limit.
  5736 
  5737 * Simplifier: simplification procedures may now take the current
  5738 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5739 interface), which is very useful for calling the Simplifier
  5740 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5741 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5742 low-level mk_simproc no longer applies Logic.varify internally, to
  5743 allow for use in a context of fixed variables.
  5744 
  5745 * thin_tac now works even if the assumption being deleted contains !!
  5746 or ==>.  More generally, erule now works even if the major premise of
  5747 the elimination rule contains !! or ==>.
  5748 
  5749 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5750 
  5751 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5752 from Pure, which contains all common declarations already.  Both
  5753 theories are defined via plain Isabelle/Isar .thy files.
  5754 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5755 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5756 use isatool fixcpure to adapt your theory and ML sources.
  5757 
  5758 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5759 selections of theorems in named facts via index ranges.
  5760 
  5761 * 'print_theorems': in theory mode, really print the difference
  5762 wrt. the last state (works for interactive theory development only),
  5763 in proof mode print all local facts (cf. 'print_facts');
  5764 
  5765 * 'hide': option '(open)' hides only base names.
  5766 
  5767 * More efficient treatment of intermediate checkpoints in interactive
  5768 theory development.
  5769 
  5770 * Code generator is now invoked via code_module (incremental code
  5771 generation) and code_library (modular code generation, ML structures
  5772 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5773 must be quoted when used as identifiers.
  5774 
  5775 * New 'value' command for reading, evaluating and printing terms using
  5776 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5777 quoted when used as identifier.
  5778 
  5779 
  5780 *** Locales ***
  5781 
  5782 * New commands for the interpretation of locale expressions in
  5783 theories (1), locales (2) and proof contexts (3).  These generate
  5784 proof obligations from the expression specification.  After the
  5785 obligations have been discharged, theorems of the expression are added
  5786 to the theory, target locale or proof context.  The synopsis of the
  5787 commands is a follows:
  5788 
  5789   (1) interpretation expr inst
  5790   (2) interpretation target < expr
  5791   (3) interpret expr inst
  5792 
  5793 Interpretation in theories and proof contexts require a parameter
  5794 instantiation of terms from the current context.  This is applied to
  5795 specifications and theorems of the interpreted expression.
  5796 Interpretation in locales only permits parameter renaming through the
  5797 locale expression.  Interpretation is smart in that interpretations
  5798 that are active already do not occur in proof obligations, neither are
  5799 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5800 inspect active interpretations of a particular locale.  For details,
  5801 see the Isar Reference manual.  Examples can be found in
  5802 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5803 
  5804 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5805 'interpret' instead.
  5806 
  5807 * New context element 'constrains' for adding type constraints to
  5808 parameters.
  5809 
  5810 * Context expressions: renaming of parameters with syntax
  5811 redeclaration.
  5812 
  5813 * Locale declaration: 'includes' disallowed.
  5814 
  5815 * Proper static binding of attribute syntax -- i.e. types / terms /
  5816 facts mentioned as arguments are always those of the locale definition
  5817 context, independently of the context of later invocations.  Moreover,
  5818 locale operations (renaming and type / term instantiation) are applied
  5819 to attribute arguments as expected.
  5820 
  5821 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5822 actual attributes; rare situations may require Attrib.attribute to
  5823 embed those attributes into Attrib.src that lack concrete syntax.
  5824 Attribute implementations need to cooperate properly with the static
  5825 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5826 Attrib.XXX_thm etc. already do the right thing without further
  5827 intervention.  Only unusual applications -- such as "where" or "of"
  5828 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5829 on the context and the facts involved -- may have to assign parsed
  5830 values to argument tokens explicitly.
  5831 
  5832 * Changed parameter management in theorem generation for long goal
  5833 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5834 theorem statement in rare situations.
  5835 
  5836 * Locale inspection command 'print_locale' omits notes elements.  Use
  5837 'print_locale!' to have them included in the output.
  5838 
  5839 
  5840 *** Provers ***
  5841 
  5842 * Provers/hypsubst.ML: improved version of the subst method, for
  5843 single-step rewriting: it now works in bound variable contexts. New is
  5844 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5845 rewrite a different subterm than the original subst method, which is
  5846 still available as 'simplesubst'.
  5847 
  5848 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5849 and quasi orders.
  5850 
  5851 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5852 reflexive-transitive closure of relations.
  5853 
  5854 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5855 limit (previously hard-coded with a value of 20) user-definable.
  5856 
  5857 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5858 is peformed already.  Object-logics merely need to finish their
  5859 initial simpset configuration as before.  INCOMPATIBILITY.
  5860 
  5861 
  5862 *** HOL ***
  5863 
  5864 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5865 
  5866   syntax (epsilon)
  5867     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5868 
  5869 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5870 and x-symbol; use option '-m epsilon' to get it actually printed.
  5871 Moreover, the mathematically important symbolic identifier \<epsilon>
  5872 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5873 
  5874 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5875 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5876 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5877 support corresponding Isar calculations.
  5878 
  5879 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5880 instead of ":".
  5881 
  5882 * theory SetInterval: changed the syntax for open intervals:
  5883 
  5884   Old       New
  5885   {..n(}    {..<n}
  5886   {)n..}    {n<..}
  5887   {m..n(}   {m..<n}
  5888   {)m..n}   {m<..n}
  5889   {)m..n(}  {m<..<n}
  5890 
  5891 The old syntax is still supported but will disappear in the next
  5892 release.  For conversion use the following Emacs search and replace
  5893 patterns (these are not perfect but work quite well):
  5894 
  5895   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5896   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5897 
  5898 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5899 equalities in commutative rings; method 'algebra' provides a generic
  5900 interface.
  5901 
  5902 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5903 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5904 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5905 be a tuple pattern.
  5906 
  5907 Some new syntax forms are available:
  5908 
  5909   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5910   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5911   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5912   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5913 
  5914 The latter form "\<Sum>x < k. e" used to be based on a separate
  5915 function "Summation", which has been discontinued.
  5916 
  5917 * theory Finite_Set: in structured induction proofs, the insert case
  5918 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5919 (insert F x)'.
  5920 
  5921 * The 'refute' command has been extended to support a much larger
  5922 fragment of HOL, including axiomatic type classes, constdefs and
  5923 typedefs, inductive datatypes and recursion.
  5924 
  5925 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5926 Requires zChaff with proof generation to be installed.  See
  5927 HOL/ex/SAT_Examples.thy for examples.
  5928 
  5929 * Datatype induction via method 'induct' now preserves the name of the
  5930 induction variable. For example, when proving P(xs::'a list) by
  5931 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5932 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5933 in unstructured proof scripts.
  5934 
  5935 * Reworked implementation of records.  Improved scalability for
  5936 records with many fields, avoiding performance problems for type
  5937 inference. Records are no longer composed of nested field types, but
  5938 of nested extension types. Therefore the record type only grows linear
  5939 in the number of extensions and not in the number of fields.  The
  5940 top-level (users) view on records is preserved.  Potential
  5941 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5942 old record representation. The type generated for a record is called
  5943 <record_name>_ext_type.
  5944 
  5945 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5946 proofs triggered by a record definition or a simproc (if
  5947 quick_and_dirty is enabled).  Definitions of large records can take
  5948 quite long.
  5949 
  5950 New simproc record_upd_simproc for simplification of multiple record
  5951 updates enabled by default.  Moreover, trivial updates are also
  5952 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5953 occasionally, since simplification is more powerful by default.
  5954 
  5955 * typedef: proper support for polymorphic sets, which contain extra
  5956 type-variables in the term.
  5957 
  5958 * Simplifier: automatically reasons about transitivity chains
  5959 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5960 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5961 old proofs break occasionally as simplification may now solve more
  5962 goals than previously.
  5963 
  5964 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5965 present.  Works for all partial orders (class "order"), in particular
  5966 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5967 just like y <= x.
  5968 
  5969 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5970 bound variable or a constant then the let is unfolded.  Otherwise
  5971 first a is simplified to b, and then f b is simplified to g. If
  5972 possible we abstract b from g arriving at "let x = b in h x",
  5973 otherwise we unfold the let and arrive at g.  The simproc can be
  5974 enabled/disabled by the reference use_let_simproc.  Potential
  5975 INCOMPATIBILITY since simplification is more powerful by default.
  5976 
  5977 * Classical reasoning: the meson method now accepts theorems as arguments.
  5978 
  5979 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5980 jobs to provide advice on the provability of subgoals.
  5981 
  5982 * Theory OrderedGroup and Ring_and_Field: various additions and
  5983 improvements to faciliate calculations involving equalities and
  5984 inequalities.
  5985 
  5986 The following theorems have been eliminated or modified
  5987 (INCOMPATIBILITY):
  5988 
  5989   abs_eq             now named abs_of_nonneg
  5990   abs_of_ge_0        now named abs_of_nonneg
  5991   abs_minus_eq       now named abs_of_nonpos
  5992   imp_abs_id         now named abs_of_nonneg
  5993   imp_abs_neg_id     now named abs_of_nonpos
  5994   mult_pos           now named mult_pos_pos
  5995   mult_pos_le        now named mult_nonneg_nonneg
  5996   mult_pos_neg_le    now named mult_nonneg_nonpos
  5997   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5998   mult_neg           now named mult_neg_neg
  5999   mult_neg_le        now named mult_nonpos_nonpos
  6000 
  6001 * The following lemmas in Ring_and_Field have been added to the simplifier:
  6002      
  6003      zero_le_square
  6004      not_square_less_zero 
  6005 
  6006   The following lemmas have been deleted from Real/RealPow:
  6007   
  6008      realpow_zero_zero
  6009      realpow_two
  6010      realpow_less
  6011      zero_le_power
  6012      realpow_two_le
  6013      abs_realpow_two
  6014      realpow_two_abs     
  6015 
  6016 * Theory Parity: added rules for simplifying exponents.
  6017 
  6018 * Theory List:
  6019 
  6020 The following theorems have been eliminated or modified
  6021 (INCOMPATIBILITY):
  6022 
  6023   list_all_Nil       now named list_all.simps(1)
  6024   list_all_Cons      now named list_all.simps(2)
  6025   list_all_conv      now named list_all_iff
  6026   set_mem_eq         now named mem_iff
  6027 
  6028 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  6029 asymptotic "big O" calculations.  See the notes in BigO.thy.
  6030 
  6031 
  6032 *** HOL-Complex ***
  6033 
  6034 * Theory RealDef: better support for embedding natural numbers and
  6035 integers in the reals.
  6036 
  6037 The following theorems have been eliminated or modified
  6038 (INCOMPATIBILITY):
  6039 
  6040   exp_ge_add_one_self  now requires no hypotheses
  6041   real_of_int_add      reversed direction of equality (use [symmetric])
  6042   real_of_int_minus    reversed direction of equality (use [symmetric])
  6043   real_of_int_diff     reversed direction of equality (use [symmetric])
  6044   real_of_int_mult     reversed direction of equality (use [symmetric])
  6045 
  6046 * Theory RComplete: expanded support for floor and ceiling functions.
  6047 
  6048 * Theory Ln is new, with properties of the natural logarithm
  6049 
  6050 * Hyperreal: There is a new type constructor "star" for making
  6051 nonstandard types.  The old type names are now type synonyms:
  6052 
  6053   hypreal = real star
  6054   hypnat = nat star
  6055   hcomplex = complex star
  6056 
  6057 * Hyperreal: Many groups of similarly-defined constants have been
  6058 replaced by polymorphic versions (INCOMPATIBILITY):
  6059 
  6060   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  6061 
  6062   starset      <-- starsetNat, starsetC
  6063   *s*          <-- *sNat*, *sc*
  6064   starset_n    <-- starsetNat_n, starsetC_n
  6065   *sn*         <-- *sNatn*, *scn*
  6066   InternalSets <-- InternalNatSets, InternalCSets
  6067 
  6068   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  6069   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  6070   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  6071   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  6072   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  6073 
  6074 * Hyperreal: Many type-specific theorems have been removed in favor of
  6075 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  6076 
  6077   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  6078   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  6079   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  6080   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  6081   right_minus <-- hypreal_add_minus
  6082   left_minus <-- {hypreal,hcomplex}_add_minus_left
  6083   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  6084   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  6085   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  6086   mult_1_right <-- hcomplex_mult_one_right
  6087   mult_zero_left <-- hcomplex_mult_zero_left
  6088   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  6089   right_distrib <-- hypnat_add_mult_distrib2
  6090   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  6091   right_inverse <-- hypreal_mult_inverse
  6092   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  6093   order_refl <-- {hypreal,hypnat}_le_refl
  6094   order_trans <-- {hypreal,hypnat}_le_trans
  6095   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  6096   order_less_le <-- {hypreal,hypnat}_less_le
  6097   linorder_linear <-- {hypreal,hypnat}_le_linear
  6098   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  6099   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  6100   add_nonneg_nonneg <-- hypreal_le_add_order
  6101 
  6102 * Hyperreal: Separate theorems having to do with type-specific
  6103 versions of constants have been merged into theorems that apply to the
  6104 new polymorphic constants (INCOMPATIBILITY):
  6105 
  6106   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  6107   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  6108   STAR_Un <-- {STAR,NatStar,STARC}_Un
  6109   STAR_Int <-- {STAR,NatStar,STARC}_Int
  6110   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  6111   STAR_subset <-- {STAR,NatStar,STARC}_subset
  6112   STAR_mem <-- {STAR,NatStar,STARC}_mem
  6113   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  6114   STAR_diff <-- {STAR,STARC}_diff
  6115   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  6116     STARC_hcomplex_of_complex}_image_subset
  6117   starset_n_Un <-- starset{Nat,C}_n_Un
  6118   starset_n_Int <-- starset{Nat,C}_n_Int
  6119   starset_n_Compl <-- starset{Nat,C}_n_Compl
  6120   starset_n_diff <-- starset{Nat,C}_n_diff
  6121   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  6122   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  6123   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  6124   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  6125   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  6126   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  6127   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  6128   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  6129   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  6130   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  6131   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  6132   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  6133   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  6134   starfun_diff <-- starfun{C,RC,CR}_diff
  6135   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  6136   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  6137   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  6138   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  6139   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  6140   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  6141   starfun_Id <-- starfunC_Id
  6142   starfun_approx <-- starfun{Nat,CR}_approx
  6143   starfun_capprox <-- starfun{C,RC}_capprox
  6144   starfun_abs <-- starfunNat_rabs
  6145   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  6146   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  6147   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  6148   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  6149   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  6150   starfun_add_approx <-- starfunCR_add_approx
  6151   starfun_inverse_inverse <-- starfunC_inverse_inverse
  6152   starfun_divide <-- starfun{C,CR,RC}_divide
  6153   starfun_n <-- starfun{Nat,C}_n
  6154   starfun_n_mult <-- starfun{Nat,C}_n_mult
  6155   starfun_n_add <-- starfun{Nat,C}_n_add
  6156   starfun_n_add_minus <-- starfunNat_n_add_minus
  6157   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  6158   starfun_n_minus <-- starfun{Nat,C}_n_minus
  6159   starfun_n_eq <-- starfun{Nat,C}_n_eq
  6160 
  6161   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  6162   star_n_minus <-- {hypreal,hcomplex}_minus
  6163   star_n_diff <-- {hypreal,hcomplex}_diff
  6164   star_n_mult <-- {hypreal,hcomplex}_mult
  6165   star_n_inverse <-- {hypreal,hcomplex}_inverse
  6166   star_n_le <-- {hypreal,hypnat}_le
  6167   star_n_less <-- {hypreal,hypnat}_less
  6168   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  6169   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  6170   star_n_abs <-- hypreal_hrabs
  6171   star_n_divide <-- hcomplex_divide
  6172 
  6173   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  6174   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  6175   star_of_diff <-- hypreal_of_real_diff
  6176   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  6177   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  6178   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  6179   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  6180   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  6181   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  6182   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  6183   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  6184   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  6185   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  6186   star_of_number_of <-- {hypreal,hcomplex}_number_of
  6187   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  6188   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  6189   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  6190   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  6191   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  6192   star_of_power <-- hypreal_of_real_power
  6193   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  6194 
  6195 * Hyperreal: new method "transfer" that implements the transfer
  6196 principle of nonstandard analysis. With a subgoal that mentions
  6197 nonstandard types like "'a star", the command "apply transfer"
  6198 replaces it with an equivalent one that mentions only standard types.
  6199 To be successful, all free variables must have standard types; non-
  6200 standard variables must have explicit universal quantifiers.
  6201 
  6202 * Hyperreal: A theory of Taylor series.
  6203 
  6204 
  6205 *** HOLCF ***
  6206 
  6207 * Discontinued special version of 'constdefs' (which used to support
  6208 continuous functions) in favor of the general Pure one with full
  6209 type-inference.
  6210 
  6211 * New simplification procedure for solving continuity conditions; it
  6212 is much faster on terms with many nested lambda abstractions (cubic
  6213 instead of exponential time).
  6214 
  6215 * New syntax for domain package: selector names are now optional.
  6216 Parentheses should be omitted unless argument is lazy, for example:
  6217 
  6218   domain 'a stream = cons "'a" (lazy "'a stream")
  6219 
  6220 * New command 'fixrec' for defining recursive functions with pattern
  6221 matching; defining multiple functions with mutual recursion is also
  6222 supported.  Patterns may include the constants cpair, spair, up, sinl,
  6223 sinr, or any data constructor defined by the domain package. The given
  6224 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  6225 syntax and examples.
  6226 
  6227 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  6228 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  6229 but the proof obligation additionally includes an admissibility
  6230 requirement. The packages generate instances of class cpo or pcpo,
  6231 with continuity and strictness theorems for Rep and Abs.
  6232 
  6233 * HOLCF: Many theorems have been renamed according to a more standard naming
  6234 scheme (INCOMPATIBILITY):
  6235 
  6236   foo_inject:  "foo$x = foo$y ==> x = y"
  6237   foo_eq:      "(foo$x = foo$y) = (x = y)"
  6238   foo_less:    "(foo$x << foo$y) = (x << y)"
  6239   foo_strict:  "foo$UU = UU"
  6240   foo_defined: "... ==> foo$x ~= UU"
  6241   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  6242 
  6243 
  6244 *** ZF ***
  6245 
  6246 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  6247 including the First Isomorphism Theorem (on quotienting by the kernel
  6248 of a homomorphism).
  6249 
  6250 * ZF/Simplifier: install second copy of type solver that actually
  6251 makes use of TC rules declared to Isar proof contexts (or locales);
  6252 the old version is still required for ML proof scripts.
  6253 
  6254 
  6255 *** Cube ***
  6256 
  6257 * Converted to Isar theory format; use locales instead of axiomatic
  6258 theories.
  6259 
  6260 
  6261 *** ML ***
  6262 
  6263 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6264 for ||>, ||>>, |>>,
  6265 
  6266 * Pure/library.ML no longer defines its own option datatype, but uses
  6267 that of the SML basis, which has constructors NONE and SOME instead of
  6268 None and Some, as well as exception Option.Option instead of OPTION.
  6269 The functions the, if_none, is_some, is_none have been adapted
  6270 accordingly, while Option.map replaces apsome.
  6271 
  6272 * Pure/library.ML: the exception LIST has been given up in favour of
  6273 the standard exceptions Empty and Subscript, as well as
  6274 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6275 superceded by the standard hd and tl functions etc.
  6276 
  6277 A number of basic list functions are no longer exported to the ML
  6278 toplevel, as they are variants of predefined functions.  The following
  6279 suggests how one can translate existing code:
  6280 
  6281     rev_append xs ys = List.revAppend (xs, ys)
  6282     nth_elem (i, xs) = List.nth (xs, i)
  6283     last_elem xs = List.last xs
  6284     flat xss = List.concat xss
  6285     seq fs = List.app fs
  6286     partition P xs = List.partition P xs
  6287     mapfilter f xs = List.mapPartial f xs
  6288 
  6289 * Pure/library.ML: several combinators for linear functional
  6290 transformations, notably reverse application and composition:
  6291 
  6292   x |> f                f #> g
  6293   (x, y) |-> f          f #-> g
  6294 
  6295 * Pure/library.ML: introduced/changed precedence of infix operators:
  6296 
  6297   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6298   infix 2 ?;
  6299   infix 3 o oo ooo oooo;
  6300   infix 4 ~~ upto downto;
  6301 
  6302 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6303 infix operators.
  6304 
  6305 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6306 fold_map support linear functional transformations and nesting.  For
  6307 example:
  6308 
  6309   fold f [x1, ..., xN] y =
  6310     y |> f x1 |> ... |> f xN
  6311 
  6312   (fold o fold) f [xs1, ..., xsN] y =
  6313     y |> fold f xs1 |> ... |> fold f xsN
  6314 
  6315   fold f [x1, ..., xN] =
  6316     f x1 #> ... #> f xN
  6317 
  6318   (fold o fold) f [xs1, ..., xsN] =
  6319     fold f xs1 #> ... #> fold f xsN
  6320 
  6321 * Pure/library.ML: the following selectors on type 'a option are
  6322 available:
  6323 
  6324   the:               'a option -> 'a  (*partial*)
  6325   these:             'a option -> 'a  where 'a = 'b list
  6326   the_default: 'a -> 'a option -> 'a
  6327   the_list:          'a option -> 'a list
  6328 
  6329 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6330 basic operations for association lists, following natural argument
  6331 order; moreover the explicit equality predicate passed here avoids
  6332 potentially expensive polymorphic runtime equality checks.
  6333 The old functions may be expressed as follows:
  6334 
  6335   assoc = uncurry (AList.lookup (op =))
  6336   assocs = these oo AList.lookup (op =)
  6337   overwrite = uncurry (AList.update (op =)) o swap
  6338 
  6339 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6340 
  6341   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6342   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6343 
  6344 replacing make_keylist and keyfilter (occassionally used)
  6345 Naive rewrites:
  6346 
  6347   make_keylist = AList.make
  6348   keyfilter = AList.find (op =)
  6349 
  6350 * eq_fst and eq_snd now take explicit equality parameter, thus
  6351   avoiding eqtypes. Naive rewrites:
  6352 
  6353     eq_fst = eq_fst (op =)
  6354     eq_snd = eq_snd (op =)
  6355 
  6356 * Removed deprecated apl and apr (rarely used).
  6357   Naive rewrites:
  6358 
  6359     apl (n, op) =>>= curry op n
  6360     apr (op, m) =>>= fn n => op (n, m)
  6361 
  6362 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6363 provides a reasonably efficient light-weight implementation of sets as
  6364 lists.
  6365 
  6366 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6367 few new operations; existing lookup and update are now curried to
  6368 follow natural argument order (for use with fold etc.);
  6369 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6370 
  6371 * Pure/General: output via the Isabelle channels of
  6372 writeln/warning/error etc. is now passed through Output.output, with a
  6373 hook for arbitrary transformations depending on the print_mode
  6374 (cf. Output.add_mode -- the first active mode that provides a output
  6375 function wins).  Already formatted output may be embedded into further
  6376 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6377 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6378 accommodate easy composition of diagnostic messages etc.  Programmers
  6379 rarely need to care about Output.output or Output.raw at all, with
  6380 some notable exceptions: Output.output is required when bypassing the
  6381 standard channels (writeln etc.), or in token translations to produce
  6382 properly formatted results; Output.raw is required when capturing
  6383 already output material that will eventually be presented to the user
  6384 a second time.  For the default print mode, both Output.output and
  6385 Output.raw have no effect.
  6386 
  6387 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6388 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6389 cumulative results are displayed at the end of a batch session.
  6390 
  6391 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6392 replaced by File.platform_path and File.shell_path (with appropriate
  6393 hooks).  This provides a clean interface for unusual systems where the
  6394 internal and external process view of file names are different.
  6395 
  6396 * Pure: more efficient orders for basic syntactic entities: added
  6397 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6398 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6399 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6400 orders now -- potential INCOMPATIBILITY for code that depends on a
  6401 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6402 Library.sort_strings on result).
  6403 
  6404 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6405 fold_types traverse types/terms from left to right, observing natural
  6406 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6407 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6408 
  6409 * Pure: name spaces have been refined, with significant changes of the
  6410 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6411 to extern(_table).  The plain name entry path is superceded by a
  6412 general 'naming' context, which also includes the 'policy' to produce
  6413 a fully qualified name and external accesses of a fully qualified
  6414 name; NameSpace.extend is superceded by context dependent
  6415 Sign.declare_name.  Several theory and proof context operations modify
  6416 the naming context.  Especially note Theory.restore_naming and
  6417 ProofContext.restore_naming to get back to a sane state; note that
  6418 Theory.add_path is no longer sufficient to recover from
  6419 Theory.absolute_path in particular.
  6420 
  6421 * Pure: new flags short_names (default false) and unique_names
  6422 (default true) for controlling output of qualified names.  If
  6423 short_names is set, names are printed unqualified.  If unique_names is
  6424 reset, the name prefix is reduced to the minimum required to achieve
  6425 the original result when interning again, even if there is an overlap
  6426 with earlier declarations.
  6427 
  6428 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6429 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6430 (useful for printing error messages).  INCOMPATIBILITY.
  6431 
  6432 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6433 Theory.theory are now identified, referring to the universal
  6434 Context.theory (see Pure/context.ML).  Actual signature and theory
  6435 content is managed as theory data.  The old code and interfaces were
  6436 spread over many files and structures; the new arrangement introduces
  6437 considerable INCOMPATIBILITY to gain more clarity:
  6438 
  6439   Context -- theory management operations (name, identity, inclusion,
  6440     parents, ancestors, merge, etc.), plus generic theory data;
  6441 
  6442   Sign -- logical signature and syntax operations (declaring consts,
  6443     types, etc.), plus certify/read for common entities;
  6444 
  6445   Theory -- logical theory operations (stating axioms, definitions,
  6446     oracles), plus a copy of logical signature operations (consts,
  6447     types, etc.); also a few basic management operations (Theory.copy,
  6448     Theory.merge, etc.)
  6449 
  6450 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6451 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6452 for convenience -- they merely return the theory.
  6453 
  6454 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6455 
  6456 * Pure: the Isar proof context type is already defined early in Pure
  6457 as Context.proof (note that ProofContext.context and Proof.context are
  6458 aliases, where the latter is the preferred name).  This enables other
  6459 Isabelle components to refer to that type even before Isar is present.
  6460 
  6461 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6462 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6463 any of these kinds.  For example, Sign.intern typeK is now
  6464 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6465 Theory.hide_types.  Also note that former
  6466 Theory.hide_classes/types/consts are now
  6467 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6468 internalize their arguments!  INCOMPATIBILITY.
  6469 
  6470 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6471 datatype thmref (with constructors Name and NameSelection) instead of
  6472 plain string -- INCOMPATIBILITY;
  6473 
  6474 * Pure: cases produced by proof methods specify options, where NONE
  6475 means to remove case bindings -- INCOMPATIBILITY in
  6476 (RAW_)METHOD_CASES.
  6477 
  6478 * Pure: the following operations retrieve axioms or theorems from a
  6479 theory node or theory hierarchy, respectively:
  6480 
  6481   Theory.axioms_of: theory -> (string * term) list
  6482   Theory.all_axioms_of: theory -> (string * term) list
  6483   PureThy.thms_of: theory -> (string * thm) list
  6484   PureThy.all_thms_of: theory -> (string * thm) list
  6485 
  6486 * Pure: print_tac now outputs the goal through the trace channel.
  6487 
  6488 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6489 Reference Toplevel.debug (default false) controls detailed printing
  6490 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6491 controls execution profiling -- set to 1 for time and 2 for space
  6492 (both increase the runtime).
  6493 
  6494 * Isar session: The initial use of ROOT.ML is now always timed,
  6495 i.e. the log will show the actual process times, in contrast to the
  6496 elapsed wall-clock time that the outer shell wrapper produces.
  6497 
  6498 * Simplifier: improved handling of bound variables (nameless
  6499 representation, avoid allocating new strings).  Simprocs that invoke
  6500 the Simplifier recursively should use Simplifier.inherit_bounds to
  6501 avoid local name clashes.  Failure to do so produces warnings
  6502 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6503 for further details.
  6504 
  6505 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6506 bindings for all theorems stored within a given theory; this may help
  6507 in porting non-Isar theories to Isar ones, while keeping ML proof
  6508 scripts for the time being.
  6509 
  6510 * ML operator HTML.with_charset specifies the charset begin used for
  6511 generated HTML files.  For example:
  6512 
  6513   HTML.with_charset "utf-8" use_thy "Hebrew";
  6514   HTML.with_charset "utf-8" use_thy "Chinese";
  6515 
  6516 
  6517 *** System ***
  6518 
  6519 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6520 isabelle, isatool etc.).
  6521 
  6522 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6523 isatool doc, isatool mkdir, display_drafts etc.).
  6524 
  6525 * isatool usedir: option -f allows specification of the ML file to be
  6526 used by Isabelle; default is ROOT.ML.
  6527 
  6528 * New isatool version outputs the version identifier of the Isabelle
  6529 distribution being used.
  6530 
  6531 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6532 (containing Boolean satisfiability problems) into Isabelle/HOL
  6533 theories.
  6534 
  6535 
  6536 
  6537 New in Isabelle2004 (April 2004)
  6538 --------------------------------
  6539 
  6540 *** General ***
  6541 
  6542 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6543   Replaces linorder.ML.
  6544 
  6545 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6546   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6547   (\<a>...\<z>), are now considered normal letters, and can therefore
  6548   be used anywhere where an ASCII letter (a...zA...Z) has until
  6549   now. COMPATIBILITY: This obviously changes the parsing of some
  6550   terms, especially where a symbol has been used as a binder, say
  6551   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6552   as an identifier.  Fix it by inserting a space around former
  6553   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6554   existing theory and ML files.
  6555 
  6556 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6557 
  6558 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6559   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6560   a normal (but invisible) letter. For multiple letter subscripts repeat
  6561   \<^isub> like this: x\<^isub>1\<^isub>2.
  6562 
  6563 * Pure: There are now sub-/superscripts that can span more than one
  6564   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6565   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6566   superscript. The new control characters are not identifier parts.
  6567 
  6568 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6569   content of "..." to the latex file instead of \isacntrl... . The "..."
  6570   may consist of any printable characters excluding the end bracket >.
  6571 
  6572 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6573   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6574   declare constants "final", which prevents their being given a definition
  6575   later.  It is useful for constants whose behaviour is fixed axiomatically
  6576   rather than definitionally, such as the meta-logic connectives.
  6577 
  6578 * Pure: 'instance' now handles general arities with general sorts
  6579   (i.e. intersections of classes),
  6580 
  6581 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6582   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6583   It can be changed to alter the colors/layout of generated pages.
  6584 
  6585 
  6586 *** Isar ***
  6587 
  6588 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6589   cut_tac, subgoal_tac and thin_tac:
  6590   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6591     locales are no longer forced to write Isar proof scripts.
  6592     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6593     emulations.
  6594   - INCOMPATIBILITY: names of variables to be instantiated may no
  6595     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6596     This is consistent with the instantiation attribute "where".
  6597 
  6598 * Attributes "where" and "of":
  6599   - Now take type variables of instantiated theorem into account when reading
  6600     the instantiation string.  This fixes a bug that caused instantiated
  6601     theorems to have too special types in some circumstances.
  6602   - "where" permits explicit instantiations of type variables.
  6603 
  6604 * Calculation commands "moreover" and "also" no longer interfere with
  6605   current facts ("this"), admitting arbitrary combinations with "then"
  6606   and derived forms.
  6607 
  6608 * Locales:
  6609   - Goal statements involving the context element "includes" no longer
  6610     generate theorems with internal delta predicates (those ending on
  6611     "_axioms") in the premise.
  6612     Resolve particular premise with <locale>.intro to obtain old form.
  6613   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6614     specification and "includes" elements in goal statement.
  6615   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6616     [intro?] and [elim?] (respectively) by default.
  6617   - Experimental command for instantiation of locales in proof contexts:
  6618         instantiate <label>[<attrs>]: <loc>
  6619     Instantiates locale <loc> and adds all its theorems to the current context
  6620     taking into account their attributes.  Label and attrs are optional
  6621     modifiers, like in theorem declarations.  If present, names of
  6622     instantiated theorems are qualified with <label>, and the attributes
  6623     <attrs> are applied after any attributes these theorems might have already.
  6624       If the locale has assumptions, a chained fact of the form
  6625     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6626     are derived.  The command does not support old-style locales declared
  6627     with "locale (open)".
  6628       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6629 
  6630 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6631   (Isar) contexts.
  6632 
  6633 
  6634 *** HOL ***
  6635 
  6636 * Proof import: new image HOL4 contains the imported library from
  6637   the HOL4 system with about 2500 theorems. It is imported by
  6638   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6639   can be used like any other Isabelle image.  See
  6640   HOL/Import/HOL/README for more information.
  6641 
  6642 * Simplifier:
  6643   - Much improved handling of linear and partial orders.
  6644     Reasoners for linear and partial orders are set up for type classes
  6645     "linorder" and "order" respectively, and are added to the default simpset
  6646     as solvers.  This means that the simplifier can build transitivity chains
  6647     to solve goals from the assumptions.
  6648   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6649     of blast or auto after simplification become unnecessary because the goal
  6650     is solved by simplification already.
  6651 
  6652 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6653     all proved in axiomatic type classes for semirings, rings and fields.
  6654 
  6655 * Numerics:
  6656   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6657     now formalized using the Ring_and_Field theory mentioned above.
  6658   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6659     than before, because now they are set up once in a generic manner.
  6660   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6661     Look for the general versions in Ring_and_Field (and Power if they concern
  6662     exponentiation).
  6663 
  6664 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6665 
  6666 * Records:
  6667   - Record types are now by default printed with their type abbreviation
  6668     instead of the list of all field types. This can be configured via
  6669     the reference "print_record_type_abbr".
  6670   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6671     (not enabled by default).
  6672   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6673     EX x. x = sel r to True (not enabled by default).
  6674   - Tactic "record_split_simp_tac" to split and simplify records added.
  6675 
  6676 * 'specification' command added, allowing for definition by
  6677   specification.  There is also an 'ax_specification' command that
  6678   introduces the new constants axiomatically.
  6679 
  6680 * arith(_tac) is now able to generate counterexamples for reals as well.
  6681 
  6682 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6683 
  6684 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6685   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6686 
  6687 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6688   matrix theory to linear programming.
  6689 
  6690 * Unions and Intersections:
  6691   The latex output syntax of UN and INT has been changed
  6692   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6693   i.e. the index formulae has become a subscript.
  6694   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6695 
  6696 * Unions and Intersections over Intervals:
  6697   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6698   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6699   like in normal math, and corresponding versions for < and for intersection.
  6700 
  6701 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6702   lexicographic dictonary ordering has been added as "lexord".
  6703 
  6704 * ML: the legacy theory structures Int and List have been removed. They had
  6705   conflicted with ML Basis Library structures having the same names.
  6706 
  6707 * 'refute' command added to search for (finite) countermodels.  Only works
  6708   for a fragment of HOL.  The installation of an external SAT solver is
  6709   highly recommended.  See "HOL/Refute.thy" for details.
  6710 
  6711 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6712   formulae under an assignment of free variables to random values.
  6713   In contrast to 'refute', it can deal with inductive datatypes,
  6714   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6715   for examples.
  6716 
  6717 
  6718 *** HOLCF ***
  6719 
  6720 * Streams now come with concatenation and are part of the HOLCF image
  6721 
  6722 
  6723 
  6724 New in Isabelle2003 (May 2003)
  6725 ------------------------------
  6726 
  6727 *** General ***
  6728 
  6729 * Provers/simplifier:
  6730 
  6731   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6732     Assumptions are now subject to complete mutual simplification,
  6733     not just from left to right. The simplifier now preserves
  6734     the order of assumptions.
  6735 
  6736     Potential INCOMPATIBILITY:
  6737 
  6738     -- simp sometimes diverges where the old version did
  6739        not, e.g. invoking simp on the goal
  6740 
  6741         [| P (f x); y = x; f x = f y |] ==> Q
  6742 
  6743        now gives rise to the infinite reduction sequence
  6744 
  6745         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6746 
  6747        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6748        kind of problem.
  6749 
  6750     -- Tactics combining classical reasoner and simplification (such as auto)
  6751        are also affected by this change, because many of them rely on
  6752        simp. They may sometimes diverge as well or yield a different numbers
  6753        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6754        in case of problems. Sometimes subsequent calls to the classical
  6755        reasoner will fail because a preceeding call to the simplifier too
  6756        eagerly simplified the goal, e.g. deleted redundant premises.
  6757 
  6758   - The simplifier trace now shows the names of the applied rewrite rules
  6759 
  6760   - You can limit the number of recursive invocations of the simplifier
  6761     during conditional rewriting (where the simplifie tries to solve the
  6762     conditions before applying the rewrite rule):
  6763     ML "simp_depth_limit := n"
  6764     where n is an integer. Thus you can force termination where previously
  6765     the simplifier would diverge.
  6766 
  6767   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6768 
  6769   - No longer aborts on failed congruence proof.  Instead, the
  6770     congruence is ignored.
  6771 
  6772 * Pure: New generic framework for extracting programs from constructive
  6773   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6774   as HOL/Extraction for some case studies.
  6775 
  6776 * Pure: The main goal of the proof state is no longer shown by default, only
  6777 the subgoals. This behaviour is controlled by a new flag.
  6778    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6779 (ML: Proof.show_main_goal).
  6780 
  6781 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6782 rules whose conclusion matches subgoal 1:
  6783       PG menu: Isabelle/Isar -> Show me -> matching rules
  6784 The rules are ordered by how closely they match the subgoal.
  6785 In particular, rules that solve a subgoal outright are displayed first
  6786 (or rather last, the way they are printed).
  6787 (ML: ProofGeneral.print_intros())
  6788 
  6789 * Pure: New flag trace_unify_fail causes unification to print
  6790 diagnostic information (PG: in trace buffer) when it fails. This is
  6791 useful for figuring out why single step proofs like rule, erule or
  6792 assumption failed.
  6793 
  6794 * Pure: Locale specifications now produce predicate definitions
  6795 according to the body of text (covering assumptions modulo local
  6796 definitions); predicate "loc_axioms" covers newly introduced text,
  6797 while "loc" is cumulative wrt. all included locale expressions; the
  6798 latter view is presented only on export into the global theory
  6799 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6800 on the old view without predicates;
  6801 
  6802 * Pure: predefined locales "var" and "struct" are useful for sharing
  6803 parameters (as in CASL, for example); just specify something like
  6804 ``var x + var y + struct M'' as import;
  6805 
  6806 * Pure: improved thms_containing: proper indexing of facts instead of
  6807 raw theorems; check validity of results wrt. current name space;
  6808 include local facts of proof configuration (also covers active
  6809 locales), cover fixed variables in index; may use "_" in term
  6810 specification; an optional limit for the number of printed facts may
  6811 be given (the default is 40);
  6812 
  6813 * Pure: disallow duplicate fact bindings within new-style theory files
  6814 (batch-mode only);
  6815 
  6816 * Provers: improved induct method: assumptions introduced by case
  6817 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6818 the goal statement); "foo" still refers to all facts collectively;
  6819 
  6820 * Provers: the function blast.overloaded has been removed: all constants
  6821 are regarded as potentially overloaded, which improves robustness in exchange
  6822 for slight decrease in efficiency;
  6823 
  6824 * Provers/linorder: New generic prover for transitivity reasoning over
  6825 linear orders.  Note: this prover is not efficient!
  6826 
  6827 * Isar: preview of problems to finish 'show' now produce an error
  6828 rather than just a warning (in interactive mode);
  6829 
  6830 
  6831 *** HOL ***
  6832 
  6833 * arith(_tac)
  6834 
  6835  - Produces a counter example if it cannot prove a goal.
  6836    Note that the counter example may be spurious if the goal is not a formula
  6837    of quantifier-free linear arithmetic.
  6838    In ProofGeneral the counter example appears in the trace buffer.
  6839 
  6840  - Knows about div k and mod k where k is a numeral of type nat or int.
  6841 
  6842  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6843    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6844    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6845 
  6846 * simp's arithmetic capabilities have been enhanced a bit: it now
  6847 takes ~= in premises into account (by performing a case split);
  6848 
  6849 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6850 are distributed over a sum of terms;
  6851 
  6852 * New tactic "trans_tac" and method "trans" instantiate
  6853 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6854 "<=", "<" and "=").
  6855 
  6856 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6857 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6858 
  6859 * 'typedef' command has new option "open" to suppress the set
  6860 definition;
  6861 
  6862 * functions Min and Max on finite sets have been introduced (theory
  6863 Finite_Set);
  6864 
  6865 * attribute [symmetric] now works for relations as well; it turns
  6866 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6867 
  6868 * induct over a !!-quantified statement (say !!x1..xn):
  6869   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6870 
  6871 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6872 %x. None. Warning: empty_def now refers to the previously hidden definition
  6873 of the empty set.
  6874 
  6875 * Algebra: formalization of classical algebra.  Intended as base for
  6876 any algebraic development in Isabelle.  Currently covers group theory
  6877 (up to Sylow's theorem) and ring theory (Universal Property of
  6878 Univariate Polynomials).  Contributions welcome;
  6879 
  6880 * GroupTheory: deleted, since its material has been moved to Algebra;
  6881 
  6882 * Complex: new directory of the complex numbers with numeric constants,
  6883 nonstandard complex numbers, and some complex analysis, standard and
  6884 nonstandard (Jacques Fleuriot);
  6885 
  6886 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6887 
  6888 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6889 Fleuriot);
  6890 
  6891 * Real/HahnBanach: updated and adapted to locales;
  6892 
  6893 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6894 Gray and Kramer);
  6895 
  6896 * UNITY: added the Meier-Sanders theory of progress sets;
  6897 
  6898 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6899 as abstract algorithms, instantiated to the JVM;
  6900 
  6901 * Bali: Java source language formalization. Type system, operational
  6902 semantics, axiomatic semantics. Supported language features:
  6903 classes, interfaces, objects,virtual methods, static methods,
  6904 static/instance fields, arrays, access modifiers, definite
  6905 assignment, exceptions.
  6906 
  6907 
  6908 *** ZF ***
  6909 
  6910 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6911 universe, etc.);
  6912 
  6913 * Main ZF: virtually all theories converted to new-style format;
  6914 
  6915 
  6916 *** ML ***
  6917 
  6918 * Pure: Tactic.prove provides sane interface for internal proofs;
  6919 omits the infamous "standard" operation, so this is more appropriate
  6920 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6921 
  6922 * Pure: improved error reporting of simprocs;
  6923 
  6924 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6925 up simprocs;
  6926 
  6927 
  6928 *** Document preparation ***
  6929 
  6930 * uses \par instead of \\ for line breaks in theory text. This may
  6931 shift some page breaks in large documents. To get the old behaviour
  6932 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6933 
  6934 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6935 other packages
  6936 
  6937 * \<euro> now needs package babel/greek instead of marvosym (which
  6938 broke \Rightarrow)
  6939 
  6940 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6941 textcomp package)
  6942 
  6943 
  6944 
  6945 New in Isabelle2002 (March 2002)
  6946 --------------------------------
  6947 
  6948 *** Document preparation ***
  6949 
  6950 * greatly simplified document preparation setup, including more
  6951 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6952 instructive isatool mkdir; users should basically be able to get
  6953 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6954 users may run a separate document processing stage manually like this:
  6955 "isatool usedir -D output HOL Test && isatool document Test/output";
  6956 
  6957 * theory dependency graph may now be incorporated into documents;
  6958 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6959 with \includegraphics of LaTeX;
  6960 
  6961 * proper spacing of consecutive markup elements, especially text
  6962 blocks after section headings;
  6963 
  6964 * support bold style (for single symbols only), input syntax is like
  6965 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6966 
  6967 * \<bullet> is now output as bold \cdot by default, which looks much
  6968 better in printed text;
  6969 
  6970 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6971 note that these symbols are currently unavailable in Proof General /
  6972 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6973 
  6974 * isatool latex no longer depends on changed TEXINPUTS, instead
  6975 isatool document copies the Isabelle style files to the target
  6976 location;
  6977 
  6978 
  6979 *** Isar ***
  6980 
  6981 * Pure/Provers: improved proof by cases and induction;
  6982   - 'case' command admits impromptu naming of parameters (such as
  6983     "case (Suc n)");
  6984   - 'induct' method divinates rule instantiation from the inductive
  6985     claim; no longer requires excessive ?P bindings for proper
  6986     instantiation of cases;
  6987   - 'induct' method properly enumerates all possibilities of set/type
  6988     rules; as a consequence facts may be also passed through *type*
  6989     rules without further ado;
  6990   - 'induct' method now derives symbolic cases from the *rulified*
  6991     rule (before it used to rulify cases stemming from the internal
  6992     atomized version); this means that the context of a non-atomic
  6993     statement becomes is included in the hypothesis, avoiding the
  6994     slightly cumbersome show "PROP ?case" form;
  6995   - 'induct' may now use elim-style induction rules without chaining
  6996     facts, using ``missing'' premises from the goal state; this allows
  6997     rules stemming from inductive sets to be applied in unstructured
  6998     scripts, while still benefitting from proper handling of non-atomic
  6999     statements; NB: major inductive premises need to be put first, all
  7000     the rest of the goal is passed through the induction;
  7001   - 'induct' proper support for mutual induction involving non-atomic
  7002     rule statements (uses the new concept of simultaneous goals, see
  7003     below);
  7004   - append all possible rule selections, but only use the first
  7005     success (no backtracking);
  7006   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  7007   - undeclared rule case names default to numbers 1, 2, 3, ...;
  7008   - added 'print_induct_rules' (covered by help item in recent Proof
  7009     General versions);
  7010   - moved induct/cases attributes to Pure, methods to Provers;
  7011   - generic method setup instantiated for FOL and HOL;
  7012 
  7013 * Pure: support multiple simultaneous goal statements, for example
  7014 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  7015 meta-level mechanism, this acts as if several individual goals had
  7016 been stated separately; in particular common proof methods need to be
  7017 repeated in order to cover all claims; note that a single elimination
  7018 step is *not* sufficient to establish the two conjunctions, so this
  7019 fails:
  7020 
  7021   assume "A & B" then have A and B ..   (*".." fails*)
  7022 
  7023 better use "obtain" in situations as above; alternative refer to
  7024 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  7025 
  7026 * Pure: proper integration with ``locales''; unlike the original
  7027 version by Florian Kammller, Isar locales package high-level proof
  7028 contexts rather than raw logical ones (e.g. we admit to include
  7029 attributes everywhere); operations on locales include merge and
  7030 rename; support for implicit arguments (``structures''); simultaneous
  7031 type-inference over imports and text; see also HOL/ex/Locales.thy for
  7032 some examples;
  7033 
  7034 * Pure: the following commands have been ``localized'', supporting a
  7035 target locale specification "(in name)": 'lemma', 'theorem',
  7036 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  7037 stored both within the locale and at the theory level (exported and
  7038 qualified by the locale name);
  7039 
  7040 * Pure: theory goals may now be specified in ``long'' form, with
  7041 ad-hoc contexts consisting of arbitrary locale elements. for example
  7042 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  7043 definitions may be given, too); the result is a meta-level rule with
  7044 the context elements being discharged in the obvious way;
  7045 
  7046 * Pure: new proof command 'using' allows to augment currently used
  7047 facts after a goal statement ('using' is syntactically analogous to
  7048 'apply', but acts on the goal's facts only); this allows chained facts
  7049 to be separated into parts given before and after a claim, as in
  7050 ``from a and b have C using d and e <proof>'';
  7051 
  7052 * Pure: renamed "antecedent" case to "rule_context";
  7053 
  7054 * Pure: new 'judgment' command records explicit information about the
  7055 object-logic embedding (used by several tools internally); no longer
  7056 use hard-wired "Trueprop";
  7057 
  7058 * Pure: added 'corollary' command;
  7059 
  7060 * Pure: fixed 'token_translation' command;
  7061 
  7062 * Pure: removed obsolete 'exported' attribute;
  7063 
  7064 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  7065 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  7066 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  7067 
  7068 * Pure: method 'atomize' presents local goal premises as object-level
  7069 statements (atomic meta-level propositions); setup controlled via
  7070 rewrite rules declarations of 'atomize' attribute; example
  7071 application: 'induct' method with proper rule statements in improper
  7072 proof *scripts*;
  7073 
  7074 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  7075 now consider the syntactic context of assumptions, giving a better
  7076 chance to get type-inference of the arguments right (this is
  7077 especially important for locales);
  7078 
  7079 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  7080 mode;
  7081 
  7082 * Pure/obtain: the formal conclusion "thesis", being marked as
  7083 ``internal'', may no longer be reference directly in the text;
  7084 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  7085 situations;
  7086 
  7087 * Pure: generic 'sym' attribute which declares a rule both as pure
  7088 'elim?' and for the 'symmetric' operation;
  7089 
  7090 * Pure: marginal comments ``--'' may now occur just anywhere in the
  7091 text; the fixed correlation with particular command syntax has been
  7092 discontinued;
  7093 
  7094 * Pure: new method 'rules' is particularly well-suited for proof
  7095 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  7096 but often produces more compact proof terms with less detours;
  7097 
  7098 * Pure/Provers/classical: simplified integration with pure rule
  7099 attributes and methods; the classical "intro?/elim?/dest?"
  7100 declarations coincide with the pure ones; the "rule" method no longer
  7101 includes classically swapped intros; "intro" and "elim" methods no
  7102 longer pick rules from the context; also got rid of ML declarations
  7103 AddXIs/AddXEs/AddXDs; all of this has some potential for
  7104 INCOMPATIBILITY;
  7105 
  7106 * Provers/classical: attribute 'swapped' produces classical inversions
  7107 of introduction rules;
  7108 
  7109 * Provers/simplifier: 'simplified' attribute may refer to explicit
  7110 rules instead of full simplifier context; 'iff' attribute handles
  7111 conditional rules;
  7112 
  7113 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  7114 
  7115 * HOL: 'recdef' now fails on unfinished automated proofs, use
  7116 "(permissive)" option to recover old behavior;
  7117 
  7118 * HOL: 'inductive' no longer features separate (collective) attributes
  7119 for 'intros' (was found too confusing);
  7120 
  7121 * HOL: properly declared induction rules less_induct and
  7122 wf_induct_rule;
  7123 
  7124 
  7125 *** HOL ***
  7126 
  7127 * HOL: moved over to sane numeral syntax; the new policy is as
  7128 follows:
  7129 
  7130   - 0 and 1 are polymorphic constants, which are defined on any
  7131   numeric type (nat, int, real etc.);
  7132 
  7133   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  7134   binary representation internally;
  7135 
  7136   - type nat has special constructor Suc, and generally prefers Suc 0
  7137   over 1::nat and Suc (Suc 0) over 2::nat;
  7138 
  7139 This change may cause significant problems of INCOMPATIBILITY; here
  7140 are some hints on converting existing sources:
  7141 
  7142   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  7143   entities, so expressions involving "-" (unary or binary minus) need
  7144   to be spaced properly;
  7145 
  7146   - existing occurrences of "1" may need to be constraint "1::nat" or
  7147   even replaced by Suc 0; similar for old "2";
  7148 
  7149   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  7150 
  7151   - remove all special provisions on numerals in proofs;
  7152 
  7153 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  7154 representation (depends on bin_arith_simps in the default context);
  7155 
  7156 * HOL: symbolic syntax for x^2 (numeral 2);
  7157 
  7158 * HOL: the class of all HOL types is now called "type" rather than
  7159 "term"; INCOMPATIBILITY, need to adapt references to this type class
  7160 in axclass/classes, instance/arities, and (usually rare) occurrences
  7161 in typings (of consts etc.); internally the class is called
  7162 "HOL.type", ML programs should refer to HOLogic.typeS;
  7163 
  7164 * HOL/record package improvements:
  7165   - new derived operations "fields" to build a partial record section,
  7166     "extend" to promote a fixed record to a record scheme, and
  7167     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  7168     declared as simp by default;
  7169   - shared operations ("more", "fields", etc.) now need to be always
  7170     qualified) --- potential INCOMPATIBILITY;
  7171   - removed "make_scheme" operations (use "make" with "extend") --
  7172     INCOMPATIBILITY;
  7173   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  7174   - provides cases/induct rules for use with corresponding Isar
  7175     methods (for concrete records, record schemes, concrete more
  7176     parts, and schematic more parts -- in that order);
  7177   - internal definitions directly based on a light-weight abstract
  7178     theory of product types over typedef rather than datatype;
  7179 
  7180 * HOL: generic code generator for generating executable ML code from
  7181 specifications; specific support for HOL constructs such as inductive
  7182 datatypes and sets, as well as recursive functions; can be invoked
  7183 via 'generate_code' theory section;
  7184 
  7185 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  7186 
  7187 * HOL: consolidated and renamed several theories.  In particular:
  7188         Ord.thy has been absorbed into HOL.thy
  7189         String.thy has been absorbed into List.thy
  7190 
  7191 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  7192 (beware of argument permutation!);
  7193 
  7194 * HOL: linorder_less_split superseded by linorder_cases;
  7195 
  7196 * HOL/List: "nodups" renamed to "distinct";
  7197 
  7198 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  7199 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  7200   - Ex_def has changed, now need to use some_eq_ex
  7201 
  7202 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  7203 in this (rare) case use:
  7204 
  7205   delSWrapper "split_all_tac"
  7206   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  7207 
  7208 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  7209 MAY FAIL;
  7210 
  7211 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  7212 Isabelle's type classes, ^ on functions and relations has too general
  7213 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  7214 necessary to attach explicit type constraints;
  7215 
  7216 * HOL/Relation: the prefix name of the infix "O" has been changed from
  7217 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  7218 renamed accordingly (eg "compI" -> "rel_compI").
  7219 
  7220 * HOL: syntax translations now work properly with numerals and records
  7221 expressions;
  7222 
  7223 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  7224 of "lam" -- INCOMPATIBILITY;
  7225 
  7226 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  7227 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  7228 renamed "Product_Type.unit";
  7229 
  7230 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  7231 
  7232 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  7233 the "cases" method);
  7234 
  7235 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  7236 Florian Kammller);
  7237 
  7238 * HOL/IMP: updated and converted to new-style theory format; several
  7239 parts turned into readable document, with proper Isar proof texts and
  7240 some explanations (by Gerwin Klein);
  7241 
  7242 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  7243 
  7244 * HOL-Hyperreal is now a logic image;
  7245 
  7246 
  7247 *** HOLCF ***
  7248 
  7249 * Isar: consts/constdefs supports mixfix syntax for continuous
  7250 operations;
  7251 
  7252 * Isar: domain package adapted to new-style theory format, e.g. see
  7253 HOLCF/ex/Dnat.thy;
  7254 
  7255 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7256 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7257 lift.induct_tac, always use UU instead of Undef;
  7258 
  7259 * HOLCF/IMP: updated and converted to new-style theory;
  7260 
  7261 
  7262 *** ZF ***
  7263 
  7264 * Isar: proper integration of logic-specific tools and packages,
  7265 including theory commands '(co)inductive', '(co)datatype',
  7266 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7267 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7268 
  7269 * theory Main no longer includes AC; for the Axiom of Choice, base
  7270 your theory on Main_ZFC;
  7271 
  7272 * the integer library now covers quotients and remainders, with many
  7273 laws relating division to addition, multiplication, etc.;
  7274 
  7275 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7276 typeless version of the formalism;
  7277 
  7278 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7279 format;
  7280 
  7281 * ZF/Induct: new directory for examples of inductive definitions,
  7282 including theory Multiset for multiset orderings; converted to
  7283 new-style theory format;
  7284 
  7285 * ZF: many new theorems about lists, ordinals, etc.;
  7286 
  7287 
  7288 *** General ***
  7289 
  7290 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7291 variable proof controls level of detail: 0 = no proofs (only oracle
  7292 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7293 also ref manual for further ML interfaces;
  7294 
  7295 * Pure/axclass: removed obsolete ML interface
  7296 goal_subclass/goal_arity;
  7297 
  7298 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7299 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7300 separate tokens, so expressions involving minus need to be spaced
  7301 properly;
  7302 
  7303 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7304 rather than "infixl" or "infixr";
  7305 
  7306 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7307 sort constraint specifications in type inference; e.g. "x::_::foo"
  7308 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7309 type variable);
  7310 
  7311 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7312 control output of nested => (types); the default behavior is
  7313 "type_brackets";
  7314 
  7315 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7316 tokens into AST constants;
  7317 
  7318 * Pure/syntax: prefer later declarations of translations and print
  7319 translation functions; potential INCOMPATIBILITY: need to reverse
  7320 multiple declarations for same syntax element constant;
  7321 
  7322 * Pure/show_hyps reset by default (in accordance to existing Isar
  7323 practice);
  7324 
  7325 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7326 addSafter;
  7327 
  7328 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7329 as well;
  7330 
  7331 * system: tested support for MacOS X; should be able to get Isabelle +
  7332 Proof General to work in a plain Terminal after installing Poly/ML
  7333 (e.g. from the Isabelle distribution area) and GNU bash alone
  7334 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7335 support requires further installations, e.g. from
  7336 http://fink.sourceforge.net/);
  7337 
  7338 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7339 
  7340 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7341 of 40 MB), cf. ML_OPTIONS;
  7342 
  7343 * system: Proof General keywords specification is now part of the
  7344 Isabelle distribution (see etc/isar-keywords.el);
  7345 
  7346 * system: support for persistent Proof General sessions (refrain from
  7347 outdating all loaded theories on startup); user may create writable
  7348 logic images like this: ``isabelle -q HOL Test'';
  7349 
  7350 * system: smart selection of Isabelle process versus Isabelle
  7351 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7352 run both "isabelle" and "Isabelle" even if file names are badly
  7353 damaged (executable inspects the case of the first letter of its own
  7354 name); added separate "isabelle-process" and "isabelle-interface";
  7355 
  7356 * system: refrain from any attempt at filtering input streams; no
  7357 longer support ``8bit'' encoding of old isabelle font, instead proper
  7358 iso-latin characters may now be used; the related isatools
  7359 "symbolinput" and "nonascii" have disappeared as well;
  7360 
  7361 * system: removed old "xterm" interface (the print modes "xterm" and
  7362 "xterm_color" are still available for direct use in a suitable
  7363 terminal);
  7364 
  7365 
  7366 
  7367 New in Isabelle99-2 (February 2001)
  7368 -----------------------------------
  7369 
  7370 *** Overview of INCOMPATIBILITIES ***
  7371 
  7372 * HOL: please note that theories in the Library and elsewhere often use the
  7373 new-style (Isar) format; to refer to their theorems in an ML script you must
  7374 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  7375 
  7376 * HOL: inductive package no longer splits induction rule aggressively,
  7377 but only as far as specified by the introductions given; the old
  7378 format may be recovered via ML function complete_split_rule or attribute
  7379 'split_rule (complete)';
  7380 
  7381 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  7382 gfp_Tarski to gfp_unfold;
  7383 
  7384 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  7385 
  7386 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  7387 relation); infix "^^" has been renamed "``"; infix "``" has been
  7388 renamed "`"; "univalent" has been renamed "single_valued";
  7389 
  7390 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  7391 operation;
  7392 
  7393 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  7394 
  7395 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  7396 
  7397 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  7398 consequence, it is no longer monotonic wrt. the local goal context
  7399 (which is now passed through the inductive cases);
  7400 
  7401 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  7402 \<gg> to \<ggreater>;
  7403 
  7404 
  7405 *** Document preparation ***
  7406 
  7407 * \isabellestyle{NAME} selects version of Isabelle output (currently
  7408 available: are "it" for near math-mode best-style output, "sl" for
  7409 slanted text style, and "tt" for plain type-writer; if no
  7410 \isabellestyle command is given, output is according to slanted
  7411 type-writer);
  7412 
  7413 * support sub/super scripts (for single symbols only), input syntax is
  7414 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  7415 
  7416 * some more standard symbols; see Appendix A of the system manual for
  7417 the complete list of symbols defined in isabellesym.sty;
  7418 
  7419 * improved isabelle style files; more abstract symbol implementation
  7420 (should now use \isamath{...} and \isatext{...} in custom symbol
  7421 definitions);
  7422 
  7423 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  7424 state; Note that presentation of goal states does not conform to
  7425 actual human-readable proof documents.  Please do not include goal
  7426 states into document output unless you really know what you are doing!
  7427 
  7428 * proper indentation of antiquoted output with proportional LaTeX
  7429 fonts;
  7430 
  7431 * no_document ML operator temporarily disables LaTeX document
  7432 generation;
  7433 
  7434 * isatool unsymbolize tunes sources for plain ASCII communication;
  7435 
  7436 
  7437 *** Isar ***
  7438 
  7439 * Pure: Isar now suffers initial goal statements to contain unbound
  7440 schematic variables (this does not conform to actual readable proof
  7441 documents, due to unpredictable outcome and non-compositional proof
  7442 checking); users who know what they are doing may use schematic goals
  7443 for Prolog-style synthesis of proven results;
  7444 
  7445 * Pure: assumption method (an implicit finishing) now handles actual
  7446 rules as well;
  7447 
  7448 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  7449 initial goal, declare "that" only as Pure intro (only for single
  7450 steps); the "that" rule assumption may now be involved in implicit
  7451 finishing, thus ".." becomes a feasible for trivial obtains;
  7452 
  7453 * Pure: default proof step now includes 'intro_classes'; thus trivial
  7454 instance proofs may be performed by "..";
  7455 
  7456 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  7457 statements as well;
  7458 
  7459 * Pure: more robust selection of calculational rules;
  7460 
  7461 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  7462 rule (as well as the assumption rule);
  7463 
  7464 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  7465 lemmas, using the graph browser tool;
  7466 
  7467 * Pure: predict failure of "show" in interactive mode;
  7468 
  7469 * Pure: 'thms_containing' now takes actual terms as arguments;
  7470 
  7471 * HOL: improved method 'induct' --- now handles non-atomic goals
  7472 (potential INCOMPATIBILITY); tuned error handling;
  7473 
  7474 * HOL: cases and induct rules now provide explicit hints about the
  7475 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  7476 any remaining facts are inserted into the goal verbatim;
  7477 
  7478 * HOL: local contexts (aka cases) may now contain term bindings as
  7479 well; the 'cases' and 'induct' methods new provide a ?case binding for
  7480 the result to be shown in each case;
  7481 
  7482 * HOL: added 'recdef_tc' command;
  7483 
  7484 * isatool convert assists in eliminating legacy ML scripts;
  7485 
  7486 
  7487 *** HOL ***
  7488 
  7489 * HOL/Library: a collection of generic theories to be used together
  7490 with main HOL; the theory loader path already includes this directory
  7491 by default; the following existing theories have been moved here:
  7492 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  7493 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  7494 
  7495 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  7496 modelling and verification task performed in Isabelle/HOL +
  7497 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  7498 
  7499 * HOL/Algebra: special summation operator SUM no longer exists, it has
  7500 been replaced by setsum; infix 'assoc' now has priority 50 (like
  7501 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  7502 'domain', this makes the theory consistent with mathematical
  7503 literature;
  7504 
  7505 * HOL basics: added overloaded operations "inverse" and "divide"
  7506 (infix "/"), syntax for generic "abs" operation, generic summation
  7507 operator \<Sum>;
  7508 
  7509 * HOL/typedef: simplified package, provide more useful rules (see also
  7510 HOL/subset.thy);
  7511 
  7512 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  7513 now expressed as a proper nested rule (old-style tactic scripts may
  7514 require atomize_strip_tac to cope with non-atomic premises);
  7515 
  7516 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  7517 to "split_conv" (old name still available for compatibility);
  7518 
  7519 * HOL: improved concrete syntax for strings (e.g. allows translation
  7520 rules with string literals);
  7521 
  7522 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  7523  and Fleuriot's mechanization of analysis, including the transcendental
  7524  functions for the reals;
  7525 
  7526 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  7527 
  7528 
  7529 *** CTT ***
  7530 
  7531 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  7532 "lam" is displayed as TWO lambda-symbols
  7533 
  7534 * CTT: theory Main now available, containing everything (that is, Bool
  7535 and Arith);
  7536 
  7537 
  7538 *** General ***
  7539 
  7540 * Pure: the Simplifier has been implemented properly as a derived rule
  7541 outside of the actual kernel (at last!); the overall performance
  7542 penalty in practical applications is about 50%, while reliability of
  7543 the Isabelle inference kernel has been greatly improved;
  7544 
  7545 * print modes "brackets" and "no_brackets" control output of nested =>
  7546 (types) and ==> (props); the default behaviour is "brackets";
  7547 
  7548 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7549 as assumptions as well;
  7550 
  7551 * system: support Poly/ML 4.0;
  7552 
  7553 * system: isatool install handles KDE version 1 or 2;
  7554 
  7555 
  7556 
  7557 New in Isabelle99-1 (October 2000)
  7558 ----------------------------------
  7559 
  7560 *** Overview of INCOMPATIBILITIES ***
  7561 
  7562 * HOL: simplification of natural numbers is much changed; to partly
  7563 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7564 issue the following ML commands:
  7565 
  7566   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7567   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7568 
  7569 * HOL: simplification no longer dives into case-expressions; this is
  7570 controlled by "t.weak_case_cong" for each datatype t;
  7571 
  7572 * HOL: nat_less_induct renamed to less_induct;
  7573 
  7574 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7575 fixsome to patch .thy and .ML sources automatically;
  7576 
  7577   select_equality  -> some_equality
  7578   select_eq_Ex     -> some_eq_ex
  7579   selectI2EX       -> someI2_ex
  7580   selectI2         -> someI2
  7581   selectI          -> someI
  7582   select1_equality -> some1_equality
  7583   Eps_sym_eq       -> some_sym_eq_trivial
  7584   Eps_eq           -> some_eq_trivial
  7585 
  7586 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7587 
  7588 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7589 instead);
  7590 
  7591 * HOL: the recursion equations generated by 'recdef' are now called
  7592 f.simps instead of f.rules;
  7593 
  7594 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7595 
  7596 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7597 sometimes be needed;
  7598 
  7599 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7600 
  7601 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7602 
  7603 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7604 product is now "<*>" instead of "Times"; the lexicographic product is
  7605 now "<*lex*>" instead of "**";
  7606 
  7607 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7608 of main HOL, but was unused); better use HOL's datatype package;
  7609 
  7610 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7611 the old syntax may be recovered as follows:
  7612 
  7613   syntax (symbols)
  7614     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7615       (infixl "\\<oplus>" 100)
  7616 
  7617 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7618 
  7619 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7620 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7621 internally;
  7622 
  7623 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7624 changed from A/r to A//r;
  7625 
  7626 * ZF: new treatment of arithmetic (nat & int) may break some old
  7627 proofs;
  7628 
  7629 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7630 rulify -> rule_format, elimify -> elim_format, ...);
  7631 
  7632 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7633 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7634 should have to change intro!! to intro? only); replaced "delrule" by
  7635 "rule del";
  7636 
  7637 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7638 
  7639 * Provers: strengthened force_tac by using new first_best_tac;
  7640 
  7641 * LaTeX document preparation: several changes of isabelle.sty (see
  7642 lib/texinputs);
  7643 
  7644 
  7645 *** Document preparation ***
  7646 
  7647 * formal comments (text blocks etc.) in new-style theories may now
  7648 contain antiquotations of thm/prop/term/typ/text to be presented
  7649 according to latex print mode; concrete syntax is like this:
  7650 @{term[show_types] "f(x) = a + x"};
  7651 
  7652 * isatool mkdir provides easy setup of Isabelle session directories,
  7653 including proper document sources;
  7654 
  7655 * generated LaTeX sources are now deleted after successful run
  7656 (isatool document -c); may retain a copy somewhere else via -D option
  7657 of isatool usedir;
  7658 
  7659 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7660 style files, achieving self-contained LaTeX sources and simplifying
  7661 LaTeX debugging;
  7662 
  7663 * old-style theories now produce (crude) LaTeX output as well;
  7664 
  7665 * browser info session directories are now self-contained (may be put
  7666 on WWW server seperately); improved graphs of nested sessions; removed
  7667 graph for 'all sessions';
  7668 
  7669 * several improvements in isabelle style files; \isabellestyle{it}
  7670 produces fake math mode output; \isamarkupheader is now \section by
  7671 default; see lib/texinputs/isabelle.sty etc.;
  7672 
  7673 
  7674 *** Isar ***
  7675 
  7676 * Isar/Pure: local results and corresponding term bindings are now
  7677 subject to Hindley-Milner polymorphism (similar to ML); this
  7678 accommodates incremental type-inference very nicely;
  7679 
  7680 * Isar/Pure: new derived language element 'obtain' supports
  7681 generalized existence reasoning;
  7682 
  7683 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7684 support accumulation of results, without applying any rules yet;
  7685 useful to collect intermediate results without explicit name
  7686 references, and for use with transitivity rules with more than 2
  7687 premises;
  7688 
  7689 * Isar/Pure: scalable support for case-analysis type proofs: new
  7690 'case' language element refers to local contexts symbolically, as
  7691 produced by certain proof methods; internally, case names are attached
  7692 to theorems as "tags";
  7693 
  7694 * Isar/Pure: theory command 'hide' removes declarations from
  7695 class/type/const name spaces;
  7696 
  7697 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7698 indicate potential overloading;
  7699 
  7700 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7701 
  7702 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7703 "{a,b,c}" instead of {a,b,c};
  7704 
  7705 * Isar/Pure now provides its own version of intro/elim/dest
  7706 attributes; useful for building new logics, but beware of confusion
  7707 with the version in Provers/classical;
  7708 
  7709 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7710 case name 'antecedent';
  7711 
  7712 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7713 to the current context is now done automatically);
  7714 
  7715 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7716 for definining proof methods in ML;
  7717 
  7718 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7719 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7720 most cases, one should have to change intro!! to intro? only);
  7721 replaced "delrule" by "rule del";
  7722 
  7723 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7724 'symmetric' attribute (the latter supercedes [RS sym]);
  7725 
  7726 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7727 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7728 well (including splits);
  7729 
  7730 * Isar/Provers: Simplifier and Classical methods now support all kind
  7731 of modifiers used in the past, including 'cong', 'iff', etc.
  7732 
  7733 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7734 of Simplifier and Classical reasoner);
  7735 
  7736 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7737 now support named cases; major packages (inductive, datatype, primrec,
  7738 recdef) support case names and properly name parameters;
  7739 
  7740 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7741 monotonicity conditions are extracted to be proven at end of
  7742 calculations;
  7743 
  7744 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7745 method anyway;
  7746 
  7747 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7748 split_if split_if_asm; datatype package provides theorems foo.splits =
  7749 foo.split foo.split_asm for each datatype;
  7750 
  7751 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7752 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7753 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  7754 use "(cases (simplified))" method in proper proof texts);
  7755 
  7756 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  7757 
  7758 * Isar: names of theorems etc. may be natural numbers as well;
  7759 
  7760 * Isar: 'pr' command: optional arguments for goals_limit and
  7761 ProofContext.prems_limit; no longer prints theory contexts, but only
  7762 proof states;
  7763 
  7764 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  7765 additional print modes to be specified; e.g. "pr(latex)" will print
  7766 proof state according to the Isabelle LaTeX style;
  7767 
  7768 * Isar: improved support for emulating tactic scripts, including proof
  7769 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  7770 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  7771 (for HOL datatypes);
  7772 
  7773 * Isar: simplified (more robust) goal selection of proof methods: 1st
  7774 goal, all goals, or explicit goal specifier (tactic emulation); thus
  7775 'proof method scripts' have to be in depth-first order;
  7776 
  7777 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  7778 
  7779 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  7780 should instead use individual commands for printing items
  7781 (print_commands, print_methods etc.);
  7782 
  7783 * Isar: added 'nothing' --- the empty list of theorems;
  7784 
  7785 
  7786 *** HOL ***
  7787 
  7788 * HOL/MicroJava: formalization of a fragment of Java, together with a
  7789 corresponding virtual machine and a specification of its bytecode
  7790 verifier and a lightweight bytecode verifier, including proofs of
  7791 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  7792 Cornelia Pusch (see also the homepage of project Bali at
  7793 http://isabelle.in.tum.de/Bali/);
  7794 
  7795 * HOL/Algebra: new theory of rings and univariate polynomials, by
  7796 Clemens Ballarin;
  7797 
  7798 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  7799 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  7800 Rasmussen;
  7801 
  7802 * HOL/Lattice: fundamental concepts of lattice theory and order
  7803 structures, including duals, properties of bounds versus algebraic
  7804 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  7805 Theorem for complete lattices etc.; may also serve as a demonstration
  7806 for abstract algebraic reasoning using axiomatic type classes, and
  7807 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  7808 
  7809 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  7810 von Oheimb;
  7811 
  7812 * HOL/IMPP: extension of IMP with local variables and mutually
  7813 recursive procedures, by David von Oheimb;
  7814 
  7815 * HOL/Lambda: converted into new-style theory and document;
  7816 
  7817 * HOL/ex/Multiquote: example of multiple nested quotations and
  7818 anti-quotations -- basically a generalized version of de-Bruijn
  7819 representation; very useful in avoiding lifting of operations;
  7820 
  7821 * HOL/record: added general record equality rule to simpset; fixed
  7822 select-update simplification procedure to handle extended records as
  7823 well; admit "r" as field name;
  7824 
  7825 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  7826 other numeric types and also as the identity of groups, rings, etc.;
  7827 
  7828 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  7829 Types nat and int belong to this axclass;
  7830 
  7831 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  7832    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  7833    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  7834   two terms #m*u and #n*u are replaced by #(m+n)*u
  7835     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  7836   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  7837     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  7838 
  7839 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  7840 powerful prover for predicate logic but knows nothing of clasets; see
  7841 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  7842 
  7843 * HOL: new version of "case_tac" subsumes both boolean case split and
  7844 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  7845 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  7846 
  7847 * HOL: simplification no longer dives into case-expressions: only the
  7848 selector expression is simplified, but not the remaining arms; to
  7849 enable full simplification of case-expressions for datatype t, you may
  7850 remove t.weak_case_cong from the simpset, either globally (Delcongs
  7851 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  7852 
  7853 * HOL/recdef: the recursion equations generated by 'recdef' for
  7854 function 'f' are now called f.simps instead of f.rules; if all
  7855 termination conditions are proved automatically, these simplification
  7856 rules are added to the simpset, as in primrec; rules may be named
  7857 individually as well, resulting in a separate list of theorems for
  7858 each equation;
  7859 
  7860 * HOL/While is a new theory that provides a while-combinator. It
  7861 permits the definition of tail-recursive functions without the
  7862 provision of a termination measure. The latter is necessary once the
  7863 invariant proof rule for while is applied.
  7864 
  7865 * HOL: new (overloaded) notation for the set of elements below/above
  7866 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  7867 
  7868 * HOL: theorems impI, allI, ballI bound as "strip";
  7869 
  7870 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  7871 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  7872 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  7873 
  7874 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7875 
  7876 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  7877 main HOL, but was unused);
  7878 
  7879 * HOL: fewer consts declared as global (e.g. have to refer to
  7880 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  7881 
  7882 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  7883 in case of overlap with user translations (e.g. judgements over
  7884 tuples); (note that the underlying logical represenation is still
  7885 bogus);
  7886 
  7887 
  7888 *** ZF ***
  7889 
  7890 * ZF: simplification automatically cancels common terms in arithmetic
  7891 expressions over nat and int;
  7892 
  7893 * ZF: new treatment of nat to minimize type-checking: all operators
  7894 coerce their operands to a natural number using the function natify,
  7895 making the algebraic laws unconditional;
  7896 
  7897 * ZF: as above, for int: operators coerce their operands to an integer
  7898 using the function intify;
  7899 
  7900 * ZF: the integer library now contains many of the usual laws for the
  7901 orderings, including $<=, and monotonicity laws for $+ and $*;
  7902 
  7903 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  7904 simplification;
  7905 
  7906 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  7907 to the simplifier and classical reasoner simultaneously;
  7908 
  7909 
  7910 *** General ***
  7911 
  7912 * Provers: blast_tac now handles actual object-logic rules as
  7913 assumptions; note that auto_tac uses blast_tac internally as well;
  7914 
  7915 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  7916 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  7917 
  7918 * Provers: delrules now handles destruct rules as well (no longer need
  7919 explicit make_elim);
  7920 
  7921 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  7922   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7923 use instead the strong form,
  7924   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7925 in HOL, FOL and ZF the function cla_make_elim will create such rules
  7926 from destruct-rules;
  7927 
  7928 * Provers: Simplifier.easy_setup provides a fast path to basic
  7929 Simplifier setup for new object-logics;
  7930 
  7931 * Pure: AST translation rules no longer require constant head on LHS;
  7932 
  7933 * Pure: improved name spaces: ambiguous output is qualified; support
  7934 for hiding of names;
  7935 
  7936 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  7937 XSYMBOL_HOME; no longer need to do manual configuration in most
  7938 situations;
  7939 
  7940 * system: compression of ML heaps images may now be controlled via -c
  7941 option of isabelle and isatool usedir (currently only observed by
  7942 Poly/ML);
  7943 
  7944 * system: isatool installfonts may handle X-Symbol fonts as well (very
  7945 useful for remote X11);
  7946 
  7947 * system: provide TAGS file for Isabelle sources;
  7948 
  7949 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  7950 order;
  7951 
  7952 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  7953 timing flag supersedes proof_timing and Toplevel.trace;
  7954 
  7955 * ML: new combinators |>> and |>>> for incremental transformations
  7956 with secondary results (e.g. certain theory extensions):
  7957 
  7958 * ML: PureThy.add_defs gets additional argument to indicate potential
  7959 overloading (usually false);
  7960 
  7961 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  7962 results;
  7963 
  7964 
  7965 
  7966 New in Isabelle99 (October 1999)
  7967 --------------------------------
  7968 
  7969 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7970 
  7971 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  7972 are no longer simplified.  (This allows the simplifier to unfold recursive
  7973 functional programs.)  To restore the old behaviour, declare
  7974 
  7975     Delcongs [if_weak_cong];
  7976 
  7977 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  7978 complement;
  7979 
  7980 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  7981 
  7982 * HOL/datatype: mutual_induct_tac no longer exists --
  7983   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  7984 
  7985 * HOL/typedef: fixed type inference for representing set; type
  7986 arguments now have to occur explicitly on the rhs as type constraints;
  7987 
  7988 * ZF: The con_defs part of an inductive definition may no longer refer
  7989 to constants declared in the same theory;
  7990 
  7991 * HOL, ZF: the function mk_cases, generated by the inductive
  7992 definition package, has lost an argument.  To simplify its result, it
  7993 uses the default simpset instead of a supplied list of theorems.
  7994 
  7995 * HOL/List: the constructors of type list are now Nil and Cons;
  7996 
  7997 * Simplifier: the type of the infix ML functions
  7998         setSSolver addSSolver setSolver addSolver
  7999 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  8000 for packaging solvers. A solver is created via
  8001         mk_solver: string -> (thm list -> int -> tactic) -> solver
  8002 where the string argument is only a comment.
  8003 
  8004 
  8005 *** Proof tools ***
  8006 
  8007 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  8008 decision procedure for linear arithmetic. Currently it is used for
  8009 types `nat', `int', and `real' in HOL (see below); it can, should and
  8010 will be instantiated for other types and logics as well.
  8011 
  8012 * The simplifier now accepts rewrite rules with flexible heads, eg
  8013      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  8014   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  8015   matching.
  8016 
  8017 
  8018 *** General ***
  8019 
  8020 * New Isabelle/Isar subsystem provides an alternative to traditional
  8021 tactical theorem proving; together with the ProofGeneral/isar user
  8022 interface it offers an interactive environment for developing human
  8023 readable proof documents (Isar == Intelligible semi-automated
  8024 reasoning); for further information see isatool doc isar-ref,
  8025 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  8026 
  8027 * improved and simplified presentation of theories: better HTML markup
  8028 (including colors), graph views in several sizes; isatool usedir now
  8029 provides a proper interface for user theories (via -P option); actual
  8030 document preparation based on (PDF)LaTeX is available as well (for
  8031 new-style theories only); see isatool doc system for more information;
  8032 
  8033 * native support for Proof General, both for classic Isabelle and
  8034 Isabelle/Isar;
  8035 
  8036 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  8037 using the graph browser tool;
  8038 
  8039 * Isabelle manuals now also available as PDF;
  8040 
  8041 * theory loader rewritten from scratch (may not be fully
  8042 bug-compatible); old loadpath variable has been replaced by show_path,
  8043 add_path, del_path, reset_path functions; new operations such as
  8044 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  8045 isatool doc ref);
  8046 
  8047 * improved isatool install: option -k creates KDE application icon,
  8048 option -p DIR installs standalone binaries;
  8049 
  8050 * added ML_PLATFORM setting (useful for cross-platform installations);
  8051 more robust handling of platform specific ML images for SML/NJ;
  8052 
  8053 * the settings environment is now statically scoped, i.e. it is never
  8054 created again in sub-processes invoked from isabelle, isatool, or
  8055 Isabelle;
  8056 
  8057 * path element specification '~~' refers to '$ISABELLE_HOME';
  8058 
  8059 * in locales, the "assumes" and "defines" parts may be omitted if
  8060 empty;
  8061 
  8062 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  8063 long arrows);
  8064 
  8065 * new print_mode "HTML";
  8066 
  8067 * new flag show_tags controls display of tags of theorems (which are
  8068 basically just comments that may be attached by some tools);
  8069 
  8070 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  8071 mode and goal output format:
  8072 
  8073 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  8074 244c244
  8075 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  8076 ---
  8077 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  8078 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  8079 181c181
  8080 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  8081 ---
  8082 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  8083 
  8084 * function bind_thms stores lists of theorems (cf. bind_thm);
  8085 
  8086 * new shorthand tactics ftac, eatac, datac, fatac;
  8087 
  8088 * qed (and friends) now accept "" as result name; in that case the
  8089 theorem is not stored, but proper checks and presentation of the
  8090 result still apply;
  8091 
  8092 * theorem database now also indexes constants "Trueprop", "all",
  8093 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  8094 
  8095 
  8096 *** HOL ***
  8097 
  8098 ** HOL arithmetic **
  8099 
  8100 * There are now decision procedures for linear arithmetic over nat and
  8101 int:
  8102 
  8103 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  8104 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  8105 are treated as atomic; subformulae not involving type `nat' or `int'
  8106 are ignored; quantified subformulae are ignored unless they are
  8107 positive universal or negative existential. The tactic has to be
  8108 invoked by hand and can be a little bit slow. In particular, the
  8109 running time is exponential in the number of occurrences of `min' and
  8110 `max', and `-' on `nat'.
  8111 
  8112 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  8113 (negated) (in)equalities among the premises and the conclusion into
  8114 account (i.e. no compound formulae) and does not know about `min' and
  8115 `max', and `-' on `nat'. It is fast and is used automatically by the
  8116 simplifier.
  8117 
  8118 NB: At the moment, these decision procedures do not cope with mixed
  8119 nat/int formulae where the two parts interact, such as `m < n ==>
  8120 int(m) < int(n)'.
  8121 
  8122 * HOL/Numeral provides a generic theory of numerals (encoded
  8123 efficiently as bit strings); setup for types nat/int/real is in place;
  8124 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  8125 int, existing theories and proof scripts may require a few additional
  8126 type constraints;
  8127 
  8128 * integer division and remainder can now be performed on constant
  8129 arguments;
  8130 
  8131 * many properties of integer multiplication, division and remainder
  8132 are now available;
  8133 
  8134 * An interface to the Stanford Validity Checker (SVC) is available through the
  8135 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  8136 are proved automatically.  SVC must be installed separately, and its results
  8137 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  8138 invocation of the underlying oracle).  For SVC see
  8139   http://verify.stanford.edu/SVC
  8140 
  8141 * IsaMakefile: the HOL-Real target now builds an actual image;
  8142 
  8143 
  8144 ** HOL misc **
  8145 
  8146 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  8147 (in Isabelle/Isar) -- by Gertrud Bauer;
  8148 
  8149 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  8150 analysis for assembly languages with subtypes;
  8151 
  8152 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  8153 -- avoids syntactic ambiguities and treats state, transition, and
  8154 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  8155 changed syntax and (many) tactics;
  8156 
  8157 * HOL/inductive: Now also handles more general introduction rules such
  8158   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  8159   theorems are now maintained within the theory (maintained via the
  8160   "mono" attribute);
  8161 
  8162 * HOL/datatype: Now also handles arbitrarily branching datatypes
  8163   (using function types) such as
  8164 
  8165   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  8166 
  8167 * HOL/record: record_simproc (part of the default simpset) takes care
  8168 of selectors applied to updated records; record_split_tac is no longer
  8169 part of the default claset; update_defs may now be removed from the
  8170 simpset in many cases; COMPATIBILITY: old behavior achieved by
  8171 
  8172   claset_ref () := claset() addSWrapper record_split_wrapper;
  8173   Delsimprocs [record_simproc]
  8174 
  8175 * HOL/typedef: fixed type inference for representing set; type
  8176 arguments now have to occur explicitly on the rhs as type constraints;
  8177 
  8178 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  8179 names rather than an ML expression;
  8180 
  8181 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  8182 supplied later.  Program schemes can be defined, such as
  8183     "While B C s = (if B s then While B C (C s) else s)"
  8184 where the well-founded relation can be chosen after B and C have been given.
  8185 
  8186 * HOL/List: the constructors of type list are now Nil and Cons;
  8187 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  8188 course, ML tools referring to List.list.op # etc. have to be adapted;
  8189 
  8190 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  8191 disabled by default; run isabelle with option -m HOL to get back to
  8192 the original Gordon/HOL-style output;
  8193 
  8194 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  8195 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  8196 
  8197 * HOL basic syntax simplified (more orthogonal): all variants of
  8198 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  8199 Eps operator is provided as well: "SOME x. P[x]";
  8200 
  8201 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  8202 
  8203 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  8204 thus available for user theories;
  8205 
  8206 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  8207 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  8208 time;
  8209 
  8210 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  8211 several times and then mp;
  8212 
  8213 
  8214 *** LK ***
  8215 
  8216 * the notation <<...>> is now available as a notation for sequences of
  8217 formulas;
  8218 
  8219 * the simplifier is now installed
  8220 
  8221 * the axiom system has been generalized (thanks to Soren Heilmann)
  8222 
  8223 * the classical reasoner now has a default rule database
  8224 
  8225 
  8226 *** ZF ***
  8227 
  8228 * new primrec section allows primitive recursive functions to be given
  8229 directly (as in HOL) over datatypes and the natural numbers;
  8230 
  8231 * new tactics induct_tac and exhaust_tac for induction (or case
  8232 analysis) over datatypes and the natural numbers;
  8233 
  8234 * the datatype declaration of type T now defines the recursor T_rec;
  8235 
  8236 * simplification automatically does freeness reasoning for datatype
  8237 constructors;
  8238 
  8239 * automatic type-inference, with AddTCs command to insert new
  8240 type-checking rules;
  8241 
  8242 * datatype introduction rules are now added as Safe Introduction rules
  8243 to the claset;
  8244 
  8245 * the syntax "if P then x else y" is now available in addition to
  8246 if(P,x,y);
  8247 
  8248 
  8249 *** Internal programming interfaces ***
  8250 
  8251 * tuned simplifier trace output; new flag debug_simp;
  8252 
  8253 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8254 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8255 
  8256 * AxClass.axclass_tac lost the theory argument;
  8257 
  8258 * tuned current_goals_markers semantics: begin / end goal avoids
  8259 printing empty lines;
  8260 
  8261 * removed prs and prs_fn hook, which was broken because it did not
  8262 include \n in its semantics, forcing writeln to add one
  8263 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8264 string -> unit if you really want to output text without newline;
  8265 
  8266 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8267 plain output, interface builders may have to enable 'isabelle_font'
  8268 mode to get Isabelle font glyphs as before;
  8269 
  8270 * refined token_translation interface; INCOMPATIBILITY: output length
  8271 now of type real instead of int;
  8272 
  8273 * theory loader actions may be traced via new ThyInfo.add_hook
  8274 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8275 your own database of information attached to *whole* theories -- as
  8276 opposed to intra-theory data slots offered via TheoryDataFun;
  8277 
  8278 * proper handling of dangling sort hypotheses (at last!);
  8279 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8280 extra sort hypotheses that can be witnessed from the type signature;
  8281 the force_strip_shyps flag is gone, any remaining shyps are simply
  8282 left in the theorem (with a warning issued by strip_shyps_warning);
  8283 
  8284 
  8285 
  8286 New in Isabelle98-1 (October 1998)
  8287 ----------------------------------
  8288 
  8289 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8290 
  8291 * several changes of automated proof tools;
  8292 
  8293 * HOL: major changes to the inductive and datatype packages, including
  8294 some minor incompatibilities of theory syntax;
  8295 
  8296 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8297 called `inj_on';
  8298 
  8299 * HOL: removed duplicate thms in Arith:
  8300   less_imp_add_less  should be replaced by  trans_less_add1
  8301   le_imp_add_le      should be replaced by  trans_le_add1
  8302 
  8303 * HOL: unary minus is now overloaded (new type constraints may be
  8304 required);
  8305 
  8306 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8307 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8308 now taken as an integer constant.
  8309 
  8310 * Pure: ML function 'theory_of' renamed to 'theory';
  8311 
  8312 
  8313 *** Proof tools ***
  8314 
  8315 * Simplifier:
  8316   1. Asm_full_simp_tac is now more aggressive.
  8317      1. It will sometimes reorient premises if that increases their power to
  8318         simplify.
  8319      2. It does no longer proceed strictly from left to right but may also
  8320         rotate premises to achieve further simplification.
  8321      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8322      old Asm_full_simp_tac in that it does not rotate premises.
  8323   2. The simplifier now knows a little bit about nat-arithmetic.
  8324 
  8325 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8326 allows for selected deletion of wrappers, by introduction of names for
  8327 wrapper functionals.  This implies that addbefore, addSbefore,
  8328 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8329 and that adding two tactics with the same name overwrites the first
  8330 one (emitting a warning).
  8331   type wrapper = (int -> tactic) -> (int -> tactic)
  8332   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8333   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8334   delWrapper, delSWrapper: claset *  string            -> claset
  8335   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8336 
  8337 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8338 semantics; addbefore now affects only the unsafe part of step_tac
  8339 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8340 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8341 by Force_tac;
  8342 
  8343 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8344 compWrapper; added safe wrapper (and access functions for it);
  8345 
  8346 * HOL/split_all_tac is now much faster and fails if there is nothing
  8347 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8348 and the names of the automatically generated variables have changed.
  8349 split_all_tac has moved within claset() from unsafe wrappers to safe
  8350 wrappers, which means that !!-bound variables are split much more
  8351 aggressively, and safe_tac and clarify_tac now split such variables.
  8352 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8353 Note: the same holds for record_split_tac, which does the job of
  8354 split_all_tac for record fields.
  8355 
  8356 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8357 permanently to the default simpset using Addsplits just like
  8358 Addsimps. They can be removed via Delsplits just like
  8359 Delsimps. Lower-case versions are also available.
  8360 
  8361 * HOL/Simplifier: The rule split_if is now part of the default
  8362 simpset. This means that the simplifier will eliminate all occurrences
  8363 of if-then-else in the conclusion of a goal. To prevent this, you can
  8364 either remove split_if completely from the default simpset by
  8365 `Delsplits [split_if]' or remove it in a specific call of the
  8366 simplifier using `... delsplits [split_if]'.  You can also add/delete
  8367 other case splitting rules to/from the default simpset: every datatype
  8368 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  8369 t is the name of the datatype).
  8370 
  8371 * Classical reasoner / Simplifier combination: new force_tac (and
  8372 derivatives Force_tac, force) combines rewriting and classical
  8373 reasoning (and whatever other tools) similarly to auto_tac, but is
  8374 aimed to solve the given subgoal completely.
  8375 
  8376 
  8377 *** General ***
  8378 
  8379 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  8380 and `goalw': the theory is no longer needed as an explicit argument -
  8381 the current theory context is used; assumptions are no longer returned
  8382 at the ML-level unless one of them starts with ==> or !!; it is
  8383 recommended to convert to these new commands using isatool fixgoal
  8384 (backup your sources first!);
  8385 
  8386 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  8387 the current theory context, and 'theory' to lookup stored theories;
  8388 
  8389 * new theory section 'locale' for declaring constants, assumptions and
  8390 definitions that have local scope;
  8391 
  8392 * new theory section 'nonterminals' for purely syntactic types;
  8393 
  8394 * new theory section 'setup' for generic ML setup functions
  8395 (e.g. package initialization);
  8396 
  8397 * the distribution now includes Isabelle icons: see
  8398 lib/logo/isabelle-{small,tiny}.xpm;
  8399 
  8400 * isatool install - install binaries with absolute references to
  8401 ISABELLE_HOME/bin;
  8402 
  8403 * isatool logo -- create instances of the Isabelle logo (as EPS);
  8404 
  8405 * print mode 'emacs' reserved for Isamode;
  8406 
  8407 * support multiple print (ast) translations per constant name;
  8408 
  8409 * theorems involving oracles are now printed with a suffixed [!];
  8410 
  8411 
  8412 *** HOL ***
  8413 
  8414 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  8415 
  8416 * HOL/inductive package reorganized and improved: now supports mutual
  8417 definitions such as
  8418 
  8419   inductive EVEN ODD
  8420     intrs
  8421       null "0 : EVEN"
  8422       oddI "n : EVEN ==> Suc n : ODD"
  8423       evenI "n : ODD ==> Suc n : EVEN"
  8424 
  8425 new theorem list "elims" contains an elimination rule for each of the
  8426 recursive sets; inductive definitions now handle disjunctive premises
  8427 correctly (also ZF);
  8428 
  8429 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  8430 "mutual_induct" no longer exists - the induction rule is always
  8431 contained in "induct";
  8432 
  8433 
  8434 * HOL/datatype package re-implemented and greatly improved: now
  8435 supports mutually recursive datatypes such as
  8436 
  8437   datatype
  8438     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  8439             | SUM ('a aexp) ('a aexp)
  8440             | DIFF ('a aexp) ('a aexp)
  8441             | NUM 'a
  8442   and
  8443     'a bexp = LESS ('a aexp) ('a aexp)
  8444             | AND ('a bexp) ('a bexp)
  8445             | OR ('a bexp) ('a bexp)
  8446 
  8447 as well as indirectly recursive datatypes such as
  8448 
  8449   datatype
  8450     ('a, 'b) term = Var 'a
  8451                   | App 'b ((('a, 'b) term) list)
  8452 
  8453 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  8454 induction on mutually / indirectly recursive datatypes.
  8455 
  8456 Primrec equations are now stored in theory and can be accessed via
  8457 <function_name>.simps.
  8458 
  8459 INCOMPATIBILITIES:
  8460 
  8461   - Theories using datatypes must now have theory Datatype as an
  8462     ancestor.
  8463   - The specific <typename>.induct_tac no longer exists - use the
  8464     generic induct_tac instead.
  8465   - natE has been renamed to nat.exhaust - use exhaust_tac
  8466     instead of res_inst_tac ... natE. Note that the variable
  8467     names in nat.exhaust differ from the names in natE, this
  8468     may cause some "fragile" proofs to fail.
  8469   - The theorems split_<typename>_case and split_<typename>_case_asm
  8470     have been renamed to <typename>.split and <typename>.split_asm.
  8471   - Since default sorts of type variables are now handled correctly,
  8472     some datatype definitions may have to be annotated with explicit
  8473     sort constraints.
  8474   - Primrec definitions no longer require function name and type
  8475     of recursive argument.
  8476 
  8477 Consider using isatool fixdatatype to adapt your theories and proof
  8478 scripts to the new package (backup your sources first!).
  8479 
  8480 
  8481 * HOL/record package: considerably improved implementation; now
  8482 includes concrete syntax for record types, terms, updates; theorems
  8483 for surjective pairing and splitting !!-bound record variables; proof
  8484 support is as follows:
  8485 
  8486   1) standard conversions (selectors or updates applied to record
  8487 constructor terms) are part of the standard simpset;
  8488 
  8489   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  8490 made part of standard simpset and claset via addIffs;
  8491 
  8492   3) a tactic for record field splitting (record_split_tac) is part of
  8493 the standard claset (addSWrapper);
  8494 
  8495 To get a better idea about these rules you may retrieve them via
  8496 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  8497 the name of your record type.
  8498 
  8499 The split tactic 3) conceptually simplifies by the following rule:
  8500 
  8501   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  8502 
  8503 Thus any record variable that is bound by meta-all will automatically
  8504 blow up into some record constructor term, consequently the
  8505 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  8506 solve record problems automatically.
  8507 
  8508 
  8509 * reorganized the main HOL image: HOL/Integ and String loaded by
  8510 default; theory Main includes everything;
  8511 
  8512 * automatic simplification of integer sums and comparisons, using cancellation;
  8513 
  8514 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  8515 
  8516 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  8517 
  8518 * many new identities for unions, intersections, set difference, etc.;
  8519 
  8520 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  8521 called split_if, split_split, split_sum_case and split_nat_case (to go
  8522 with add/delsplits);
  8523 
  8524 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  8525 (?x::unit) = (); this is made part of the default simpset, which COULD
  8526 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  8527 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  8528 unit_abs_eta_conv is added in order to counter the effect of
  8529 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  8530 %u.f();
  8531 
  8532 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  8533 makes more sense);
  8534 
  8535 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8536   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8537   disjointness reasoning but breaking a few old proofs.
  8538 
  8539 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  8540 to 'converse' from 'inverse' (for compatibility with ZF and some
  8541 literature);
  8542 
  8543 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  8544 the well-founded relation;
  8545 
  8546 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8547     Compl A.  The "Compl" syntax remains available as input syntax for this
  8548     release ONLY.
  8549 
  8550 * HOL/Update: new theory of function updates:
  8551     f(a:=b) == %x. if x=a then b else f x
  8552 may also be iterated as in f(a:=b,c:=d,...);
  8553 
  8554 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8555 
  8556 * HOL/List:
  8557   - new function list_update written xs[i:=v] that updates the i-th
  8558     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8559   - new function `upt' written [i..j(] which generates the list
  8560     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8561     bound write [i..j], which is a shorthand for [i..j+1(].
  8562   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8563 
  8564 * HOL/Arith:
  8565   - removed 'pred' (predecessor) function;
  8566   - generalized some theorems about n-1;
  8567   - many new laws about "div" and "mod";
  8568   - new laws about greatest common divisors (see theory ex/Primes);
  8569 
  8570 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8571 instead of "inverse";
  8572 
  8573 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8574   of the multiset ordering;
  8575 
  8576 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8577   (not included by default);
  8578 
  8579 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8580 
  8581 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8582   programs, i.e. different program variables may have different types.
  8583 
  8584 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8585   [previously, this check worked only if the rewrite rule was unconditional]
  8586   Now rew can involve either definitions or equalities (either == or =).
  8587 
  8588 
  8589 *** ZF ***
  8590 
  8591 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8592   only the theorems proved on ZF.ML;
  8593 
  8594 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8595   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8596   disjointness reasoning but breaking a few old proofs.
  8597 
  8598 * ZF/Update: new theory of function updates
  8599     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8600   may also be iterated as in f(a:=b,c:=d,...);
  8601 
  8602 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8603 
  8604 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8605   [previously, this check worked only if the rewrite rule was unconditional]
  8606   Now rew can involve either definitions or equalities (either == or =).
  8607 
  8608 * case_tac provided for compatibility with HOL
  8609     (like the old excluded_middle_tac, but with subgoals swapped)
  8610 
  8611 
  8612 *** Internal programming interfaces ***
  8613 
  8614 * Pure: several new basic modules made available for general use, see
  8615 also src/Pure/README;
  8616 
  8617 * improved the theory data mechanism to support encapsulation (data
  8618 kind name replaced by private Object.kind, acting as authorization
  8619 key); new type-safe user interface via functor TheoryDataFun; generic
  8620 print_data function becomes basically useless;
  8621 
  8622 * removed global_names compatibility flag -- all theory declarations
  8623 are qualified by default;
  8624 
  8625 * module Pure/Syntax now offers quote / antiquote translation
  8626 functions (useful for Hoare logic etc. with implicit dependencies);
  8627 see HOL/ex/Antiquote for an example use;
  8628 
  8629 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8630 cterm -> thm;
  8631 
  8632 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8633 subgoal;
  8634 
  8635 * Display.print_goals function moved to Locale.print_goals;
  8636 
  8637 * standard print function for goals supports current_goals_markers
  8638 variable for marking begin of proof, end of proof, start of goal; the
  8639 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8640 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8641 for example;
  8642 
  8643 
  8644 
  8645 New in Isabelle98 (January 1998)
  8646 --------------------------------
  8647 
  8648 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8649 
  8650 * changed lexical syntax of terms / types: dots made part of long
  8651 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8652 
  8653 * simpset (and claset) reference variable replaced by functions
  8654 simpset / simpset_ref;
  8655 
  8656 * no longer supports theory aliases (via merge) and non-trivial
  8657 implicit merge of thms' signatures;
  8658 
  8659 * most internal names of constants changed due to qualified names;
  8660 
  8661 * changed Pure/Sequence interface (see Pure/seq.ML);
  8662 
  8663 
  8664 *** General Changes ***
  8665 
  8666 * hierachically structured name spaces (for consts, types, axms, thms
  8667 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8668 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8669 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8670 long_names for fully qualified output names; NOTE: ML programs
  8671 (special tactics, packages etc.) referring to internal names may have
  8672 to be adapted to cope with fully qualified names; in case of severe
  8673 backward campatibility problems try setting 'global_names' at compile
  8674 time to have enrything declared within a flat name space; one may also
  8675 fine tune name declarations in theories via the 'global' and 'local'
  8676 section;
  8677 
  8678 * reimplemented the implicit simpset and claset using the new anytype
  8679 data filed in signatures; references simpset:simpset ref etc. are
  8680 replaced by functions simpset:unit->simpset and
  8681 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8682 to patch your ML files accordingly;
  8683 
  8684 * HTML output now includes theory graph data for display with Java
  8685 applet or isatool browser; data generated automatically via isatool
  8686 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8687 
  8688 * defs may now be conditional; improved rewrite_goals_tac to handle
  8689 conditional equations;
  8690 
  8691 * defs now admits additional type arguments, using TYPE('a) syntax;
  8692 
  8693 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8694 creates a new theory node; implicit merge of thms' signatures is
  8695 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8696 transfer:theory->thm->thm in (rare) cases;
  8697 
  8698 * improved handling of draft signatures / theories; draft thms (and
  8699 ctyps, cterms) are automatically promoted to real ones;
  8700 
  8701 * slightly changed interfaces for oracles: admit many per theory, named
  8702 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8703 
  8704 * print_goals: optional output of const types (set show_consts and
  8705 show_types);
  8706 
  8707 * improved output of warnings (###) and errors (***);
  8708 
  8709 * subgoal_tac displays a warning if the new subgoal has type variables;
  8710 
  8711 * removed old README and Makefiles;
  8712 
  8713 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8714 
  8715 * removed obsolete init_pps and init_database;
  8716 
  8717 * deleted the obsolete tactical STATE, which was declared by
  8718     fun STATE tacfun st = tacfun st st;
  8719 
  8720 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8721 (which abbreviates $HOME);
  8722 
  8723 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8724 use isatool fixseq to adapt your ML programs (this works for fully
  8725 qualified references to the Sequence structure only!);
  8726 
  8727 * use_thy no longer requires writable current directory; it always
  8728 reloads .ML *and* .thy file, if either one is out of date;
  8729 
  8730 
  8731 *** Classical Reasoner ***
  8732 
  8733 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8734 tactics that use classical reasoning to simplify a subgoal without
  8735 splitting it into several subgoals;
  8736 
  8737 * Safe_tac: like safe_tac but uses the default claset;
  8738 
  8739 
  8740 *** Simplifier ***
  8741 
  8742 * added simplification meta rules:
  8743     (asm_)(full_)simplify: simpset -> thm -> thm;
  8744 
  8745 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8746 logics (again);
  8747 
  8748 * added prems argument to simplification procedures;
  8749 
  8750 * HOL, FOL, ZF: added infix function `addsplits':
  8751   instead of `<simpset> setloop (split_tac <thms>)'
  8752   you can simply write `<simpset> addsplits <thms>'
  8753 
  8754 
  8755 *** Syntax ***
  8756 
  8757 * TYPE('a) syntax for type reflection terms;
  8758 
  8759 * no longer handles consts with name "" -- declare as 'syntax' instead;
  8760 
  8761 * pretty printer: changed order of mixfix annotation preference (again!);
  8762 
  8763 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  8764 
  8765 
  8766 *** HOL ***
  8767 
  8768 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8769   with `addloop' of the simplifier to faciliate case splitting in premises.
  8770 
  8771 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  8772 
  8773 * HOL/Auth: new protocol proofs including some for the Internet
  8774   protocol TLS;
  8775 
  8776 * HOL/Map: new theory of `maps' a la VDM;
  8777 
  8778 * HOL/simplifier: simplification procedures nat_cancel_sums for
  8779 cancelling out common nat summands from =, <, <= (in)equalities, or
  8780 differences; simplification procedures nat_cancel_factor for
  8781 cancelling common factor from =, <, <= (in)equalities over natural
  8782 sums; nat_cancel contains both kinds of procedures, it is installed by
  8783 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  8784 
  8785 * HOL/simplifier: terms of the form
  8786   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  8787   are rewritten to
  8788   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  8789   and those of the form
  8790   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  8791   are rewritten to
  8792   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  8793 
  8794 * HOL/datatype
  8795   Each datatype `t' now comes with a theorem `split_t_case' of the form
  8796 
  8797   P(t_case f1 ... fn x) =
  8798      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  8799         ...
  8800        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  8801      )
  8802 
  8803   and a theorem `split_t_case_asm' of the form
  8804 
  8805   P(t_case f1 ... fn x) =
  8806     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  8807         ...
  8808        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  8809      )
  8810   which can be added to a simpset via `addsplits'. The existing theorems
  8811   expand_list_case and expand_option_case have been renamed to
  8812   split_list_case and split_option_case.
  8813 
  8814 * HOL/Arithmetic:
  8815   - `pred n' is automatically converted to `n-1'.
  8816     Users are strongly encouraged not to use `pred' any longer,
  8817     because it will disappear altogether at some point.
  8818   - Users are strongly encouraged to write "0 < n" rather than
  8819     "n ~= 0". Theorems and proof tools have been modified towards this
  8820     `standard'.
  8821 
  8822 * HOL/Lists:
  8823   the function "set_of_list" has been renamed "set" (and its theorems too);
  8824   the function "nth" now takes its arguments in the reverse order and
  8825   has acquired the infix notation "!" as in "xs!n".
  8826 
  8827 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  8828 
  8829 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  8830   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  8831 
  8832 * HOL/record: extensible records with schematic structural subtyping
  8833 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  8834 still lacks various theorems and concrete record syntax;
  8835 
  8836 
  8837 *** HOLCF ***
  8838 
  8839 * removed "axioms" and "generated by" sections;
  8840 
  8841 * replaced "ops" section by extended "consts" section, which is capable of
  8842   handling the continuous function space "->" directly;
  8843 
  8844 * domain package:
  8845   . proves theorems immediately and stores them in the theory,
  8846   . creates hierachical name space,
  8847   . now uses normal mixfix annotations (instead of cinfix...),
  8848   . minor changes to some names and values (for consistency),
  8849   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  8850   . separator between mutual domain defs: changed "," to "and",
  8851   . improved handling of sort constraints;  now they have to
  8852     appear on the left-hand side of the equations only;
  8853 
  8854 * fixed LAM <x,y,zs>.b syntax;
  8855 
  8856 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  8857 adm (%x. P (t x)), where P is chainfinite and t continuous;
  8858 
  8859 
  8860 *** FOL and ZF ***
  8861 
  8862 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8863   with `addloop' of the simplifier to faciliate case splitting in premises.
  8864 
  8865 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  8866 in HOL, they strip ALL and --> from proved theorems;
  8867 
  8868 
  8869 
  8870 New in Isabelle94-8 (May 1997)
  8871 ------------------------------
  8872 
  8873 *** General Changes ***
  8874 
  8875 * new utilities to build / run / maintain Isabelle etc. (in parts
  8876 still somewhat experimental); old Makefiles etc. still functional;
  8877 
  8878 * new 'Isabelle System Manual';
  8879 
  8880 * INSTALL text, together with ./configure and ./build scripts;
  8881 
  8882 * reimplemented type inference for greater efficiency, better error
  8883 messages and clean internal interface;
  8884 
  8885 * prlim command for dealing with lots of subgoals (an easier way of
  8886 setting goals_limit);
  8887 
  8888 
  8889 *** Syntax ***
  8890 
  8891 * supports alternative (named) syntax tables (parser and pretty
  8892 printer); internal interface is provided by add_modesyntax(_i);
  8893 
  8894 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  8895 be used in conjunction with the Isabelle symbol font; uses the
  8896 "symbols" syntax table;
  8897 
  8898 * added token_translation interface (may translate name tokens in
  8899 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  8900 the current print_mode); IMPORTANT: user print translation functions
  8901 are responsible for marking newly introduced bounds
  8902 (Syntax.mark_boundT);
  8903 
  8904 * token translations for modes "xterm" and "xterm_color" that display
  8905 names in bold, underline etc. or colors (which requires a color
  8906 version of xterm);
  8907 
  8908 * infixes may now be declared with names independent of their syntax;
  8909 
  8910 * added typed_print_translation (like print_translation, but may
  8911 access type of constant);
  8912 
  8913 
  8914 *** Classical Reasoner ***
  8915 
  8916 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  8917 some limitations.  Blast_tac...
  8918   + ignores addss, addbefore, addafter; this restriction is intrinsic
  8919   + ignores elimination rules that don't have the correct format
  8920         (the conclusion MUST be a formula variable)
  8921   + ignores types, which can make HOL proofs fail
  8922   + rules must not require higher-order unification, e.g. apply_type in ZF
  8923     [message "Function Var's argument not a bound variable" relates to this]
  8924   + its proof strategy is more general but can actually be slower
  8925 
  8926 * substitution with equality assumptions no longer permutes other
  8927 assumptions;
  8928 
  8929 * minor changes in semantics of addafter (now called addaltern); renamed
  8930 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  8931 (and access functions for it);
  8932 
  8933 * improved combination of classical reasoner and simplifier:
  8934   + functions for handling clasimpsets
  8935   + improvement of addss: now the simplifier is called _after_ the
  8936     safe steps.
  8937   + safe variant of addss called addSss: uses safe simplifications
  8938     _during_ the safe steps. It is more complete as it allows multiple
  8939     instantiations of unknowns (e.g. with slow_tac).
  8940 
  8941 *** Simplifier ***
  8942 
  8943 * added interface for simplification procedures (functions that
  8944 produce *proven* rewrite rules on the fly, depending on current
  8945 redex);
  8946 
  8947 * ordering on terms as parameter (used for ordered rewriting);
  8948 
  8949 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  8950 
  8951 * the solver is now split into a safe and an unsafe part.
  8952 This should be invisible for the normal user, except that the
  8953 functions setsolver and addsolver have been renamed to setSolver and
  8954 addSolver; added safe_asm_full_simp_tac;
  8955 
  8956 
  8957 *** HOL ***
  8958 
  8959 * a generic induction tactic `induct_tac' which works for all datatypes and
  8960 also for type `nat';
  8961 
  8962 * a generic case distinction tactic `exhaust_tac' which works for all
  8963 datatypes and also for type `nat';
  8964 
  8965 * each datatype comes with a function `size';
  8966 
  8967 * patterns in case expressions allow tuple patterns as arguments to
  8968 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  8969 
  8970 * primrec now also works with type nat;
  8971 
  8972 * recdef: a new declaration form, allows general recursive functions to be
  8973 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  8974 
  8975 * the constant for negation has been renamed from "not" to "Not" to
  8976 harmonize with FOL, ZF, LK, etc.;
  8977 
  8978 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  8979 infinite lists;
  8980 
  8981 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  8982 
  8983 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  8984 problems in commutative rings, using axiomatic type classes for + and *;
  8985 
  8986 * more examples in HOL/MiniML and HOL/Auth;
  8987 
  8988 * more default rewrite rules for quantifiers, union/intersection;
  8989 
  8990 * a new constant `arbitrary == @x.False';
  8991 
  8992 * HOLCF/IOA replaces old HOL/IOA;
  8993 
  8994 * HOLCF changes: derived all rules and arities
  8995   + axiomatic type classes instead of classes
  8996   + typedef instead of faking type definitions
  8997   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  8998   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  8999   + eliminated the types void, one, tr
  9000   + use unit lift and bool lift (with translations) instead of one and tr
  9001   + eliminated blift from Lift3.thy (use Def instead of blift)
  9002   all eliminated rules are derived as theorems --> no visible changes ;
  9003 
  9004 
  9005 *** ZF ***
  9006 
  9007 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  9008 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  9009 as ZF_cs addSIs [equalityI];
  9010 
  9011 
  9012 
  9013 New in Isabelle94-7 (November 96)
  9014 ---------------------------------
  9015 
  9016 * allowing negative levels (as offsets) in prlev and choplev;
  9017 
  9018 * super-linear speedup for large simplifications;
  9019 
  9020 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  9021 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  9022 FAIL); can suppress it using the command Delsimps (ex_simps @
  9023 all_simps); De Morgan laws are also now included, by default;
  9024 
  9025 * improved printing of ==>  :  ~:
  9026 
  9027 * new object-logic "Sequents" adds linear logic, while replacing LK
  9028 and Modal (thanks to Sara Kalvala);
  9029 
  9030 * HOL/Auth: correctness proofs for authentication protocols;
  9031 
  9032 * HOL: new auto_tac combines rewriting and classical reasoning (many
  9033 examples on HOL/Auth);
  9034 
  9035 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  9036 the rewriter and classical reasoner simultaneously;
  9037 
  9038 * function uresult no longer returns theorems in "standard" format;
  9039 regain previous version by: val uresult = standard o uresult;
  9040 
  9041 
  9042 
  9043 New in Isabelle94-6
  9044 -------------------
  9045 
  9046 * oracles -- these establish an interface between Isabelle and trusted
  9047 external reasoners, which may deliver results as theorems;
  9048 
  9049 * proof objects (in particular record all uses of oracles);
  9050 
  9051 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  9052 
  9053 * "constdefs" section in theory files;
  9054 
  9055 * "primrec" section (HOL) no longer requires names;
  9056 
  9057 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  9058 
  9059 
  9060 
  9061 New in Isabelle94-5
  9062 -------------------
  9063 
  9064 * reduced space requirements;
  9065 
  9066 * automatic HTML generation from theories;
  9067 
  9068 * theory files no longer require "..." (quotes) around most types;
  9069 
  9070 * new examples, including two proofs of the Church-Rosser theorem;
  9071 
  9072 * non-curried (1994) version of HOL is no longer distributed;
  9073 
  9074 
  9075 
  9076 New in Isabelle94-4
  9077 -------------------
  9078 
  9079 * greatly reduced space requirements;
  9080 
  9081 * theory files (.thy) no longer require \...\ escapes at line breaks;
  9082 
  9083 * searchable theorem database (see the section "Retrieving theorems" on
  9084 page 8 of the Reference Manual);
  9085 
  9086 * new examples, including Grabczewski's monumental case study of the
  9087 Axiom of Choice;
  9088 
  9089 * The previous version of HOL renamed to Old_HOL;
  9090 
  9091 * The new version of HOL (previously called CHOL) uses a curried syntax
  9092 for functions.  Application looks like f a b instead of f(a,b);
  9093 
  9094 * Mutually recursive inductive definitions finally work in HOL;
  9095 
  9096 * In ZF, pattern-matching on tuples is now available in all abstractions and
  9097 translates to the operator "split";
  9098 
  9099 
  9100 
  9101 New in Isabelle94-3
  9102 -------------------
  9103 
  9104 * new infix operator, addss, allowing the classical reasoner to
  9105 perform simplification at each step of its search.  Example:
  9106         fast_tac (cs addss ss)
  9107 
  9108 * a new logic, CHOL, the same as HOL, but with a curried syntax
  9109 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  9110 look like (a,b) instead of <a,b>;
  9111 
  9112 * PLEASE NOTE: CHOL will eventually replace HOL!
  9113 
  9114 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  9115 It translates to the operator "split".  A new theory of integers is available;
  9116 
  9117 * In ZF, integer numerals now denote two's-complement binary integers.
  9118 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  9119 
  9120 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  9121 of the Axiom of Choice;
  9122 
  9123 
  9124 
  9125 New in Isabelle94-2
  9126 -------------------
  9127 
  9128 * Significantly faster resolution;
  9129 
  9130 * the different sections in a .thy file can now be mixed and repeated
  9131 freely;
  9132 
  9133 * Database of theorems for FOL, HOL and ZF.  New
  9134 commands including qed, qed_goal and bind_thm store theorems in the database.
  9135 
  9136 * Simple database queries: return a named theorem (get_thm) or all theorems of
  9137 a given theory (thms_of), or find out what theory a theorem was proved in
  9138 (theory_of_thm);
  9139 
  9140 * Bugs fixed in the inductive definition and datatype packages;
  9141 
  9142 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  9143 and HOL_dup_cs obsolete;
  9144 
  9145 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  9146 have been removed;
  9147 
  9148 * Simpler definition of function space in ZF;
  9149 
  9150 * new results about cardinal and ordinal arithmetic in ZF;
  9151 
  9152 * 'subtype' facility in HOL for introducing new types as subsets of existing
  9153 types;
  9154 
  9155 :mode=text:wrap=hard:maxLineLen=72: