NEWS
author huffman
Tue, 27 Dec 2011 15:37:33 +0100
changeset 46872 0b562d564d5f
parent 46854 f6f582a5c5fd
child 46859 40e60897ee07
permissions -rw-r--r--
redefine some binary operations on integers work on abstract numerals instead of Int.Pls and Int.Min
     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 
    14 * Rule attributes in local theory declarations (e.g. locale or class)
    15 are now statically evaluated: the resulting theorem is stored instead
    16 of the original expression.  INCOMPATIBILITY in rare situations, where
    17 the historic accident of dynamic re-evaluation in interpretations
    18 etc. was exploited.
    19 
    20 * Commands 'lemmas' and 'theorems' allow local variables using 'for'
    21 declaration, and results are standardized before being stored.  Thus
    22 old-style "standard" after instantiation or composition of facts
    23 becomes obsolete.  Minor INCOMPATIBILITY, due to potential change of
    24 indices of schematic variables.
    25 
    26 * Renamed inner syntax categories "num" to "num_token" and "xnum" to
    27 "xnum_token", in accordance to existing "float_token".  Minor
    28 INCOMPATIBILITY.  Note that in practice "num_const" etc. are mainly
    29 used instead.
    30 
    31 
    32 *** Pure ***
    33 
    34 * Obsolete command 'types' has been discontinued.  Use 'type_synonym'
    35 instead.  INCOMPATIBILITY.
    36 
    37 * Ancient code generator for SML and its commands 'code_module',
    38 'code_library', 'consts_code', 'types_code' have been discontinued.
    39 Use commands of the generic code generator instead. INCOMPATIBILITY.
    40 
    41 * Redundant attribute 'code_inline' has been discontinued. Use
    42 'code_unfold' instead. INCOMPATIBILITY.
    43 
    44 * Sort constraints are now propagated in simultaneous statements, just
    45 like type constraints.  INCOMPATIBILITY in rare situations, where
    46 distinct sorts used to be assigned accidentally.  For example:
    47 
    48   lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"
    49 
    50   lemma "P (x::'a)" and "Q (y::'a::bar)"
    51     -- "now uniform 'a::bar instead of default sort for first occurence (!)"
    52 
    53 
    54 *** HOL ***
    55 
    56 * 'set' is now a proper type constructor.  Definitions mem_def and Collect_def
    57 have disappeared.  INCOMPATIBILITY, rephrase sets S used as predicates by
    58 `%x. x : S` and predicates P used as sets by `{x. P x}`.  For typical proofs,
    59 it is often sufficent to prune any tinkering with former theorems mem_def
    60 and Collect_def.
    61 
    62 * Theory HOL/Library/AList has been renamed to AList_Impl. INCOMPABILITY.
    63 
    64 * 'datatype' specifications allow explicit sort constraints.
    65 
    66 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY, use
    67 theory HOL/Library/Nat_Bijection instead.
    68 
    69 * Session HOL-Word: Discontinued many redundant theorems specific to type
    70 'a word. INCOMPATIBILITY, use the corresponding generic theorems instead.
    71 
    72   word_sub_alt ~> word_sub_wi
    73   word_add_alt ~> word_add_def
    74   word_mult_alt ~> word_mult_def
    75   word_minus_alt ~> word_minus_def
    76   word_0_alt ~> word_0_wi
    77   word_1_alt ~> word_1_wi
    78   word_add_0 ~> add_0_left
    79   word_add_0_right ~> add_0_right
    80   word_mult_1 ~> mult_1_left
    81   word_mult_1_right ~> mult_1_right
    82   word_add_commute ~> add_commute
    83   word_add_assoc ~> add_assoc
    84   word_add_left_commute ~> add_left_commute
    85   word_mult_commute ~> mult_commute
    86   word_mult_assoc ~> mult_assoc
    87   word_mult_left_commute ~> mult_left_commute
    88   word_left_distrib ~> left_distrib
    89   word_right_distrib ~> right_distrib
    90   word_left_minus ~> left_minus
    91   word_diff_0_right ~> diff_0_right
    92   word_diff_self ~> diff_self
    93   word_sub_def ~> diff_minus
    94   word_diff_minus ~> diff_minus
    95   word_add_ac ~> add_ac
    96   word_mult_ac ~> mult_ac
    97   word_plus_ac0 ~> add_0_left add_0_right add_ac
    98   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
    99   word_order_trans ~> order_trans
   100   word_order_refl ~> order_refl
   101   word_order_antisym ~> order_antisym
   102   word_order_linear ~> linorder_linear
   103   lenw1_zero_neq_one ~> zero_neq_one
   104   word_number_of_eq ~> number_of_eq
   105 
   106 * Clarified attribute "mono_set": pure declararation without modifying
   107 the result of the fact expression.
   108 
   109 * "Transitive_Closure.ntrancl": bounded transitive closure on
   110 relations.
   111 
   112 * Constant "Set.not_member" now qualifed.  INCOMPATIBILITY.
   113 
   114 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
   115 
   116 * Theory Int: Discontinued many legacy theorems specific to type int.
   117 INCOMPATIBILITY, use the corresponding generic theorems instead.
   118 
   119   zminus_zminus ~> minus_minus
   120   zminus_0 ~> minus_zero
   121   zminus_zadd_distrib ~> minus_add_distrib
   122   zadd_commute ~> add_commute
   123   zadd_assoc ~> add_assoc
   124   zadd_left_commute ~> add_left_commute
   125   zadd_ac ~> add_ac
   126   zmult_ac ~> mult_ac
   127   zadd_0 ~> add_0_left
   128   zadd_0_right ~> add_0_right
   129   zadd_zminus_inverse2 ~> left_minus
   130   zmult_zminus ~> mult_minus_left
   131   zmult_commute ~> mult_commute
   132   zmult_assoc ~> mult_assoc
   133   zadd_zmult_distrib ~> left_distrib
   134   zadd_zmult_distrib2 ~> right_distrib
   135   zdiff_zmult_distrib ~> left_diff_distrib
   136   zdiff_zmult_distrib2 ~> right_diff_distrib
   137   zmult_1 ~> mult_1_left
   138   zmult_1_right ~> mult_1_right
   139   zle_refl ~> order_refl
   140   zle_trans ~> order_trans
   141   zle_antisym ~> order_antisym
   142   zle_linear ~> linorder_linear
   143   zless_linear ~> linorder_less_linear
   144   zadd_left_mono ~> add_left_mono
   145   zadd_strict_right_mono ~> add_strict_right_mono
   146   zadd_zless_mono ~> add_less_le_mono
   147   int_0_less_1 ~> zero_less_one
   148   int_0_neq_1 ~> zero_neq_one
   149   zless_le ~> less_le
   150   zpower_zadd_distrib ~> power_add
   151   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   152   zero_le_zpower_abs ~> zero_le_power_abs
   153 
   154 * Theory Deriv: Renamed
   155 
   156   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   157 
   158 * New "case_product" attribute to generate a case rule doing multiple
   159 case distinctions at the same time.  E.g.
   160 
   161   list.exhaust [case_product nat.exhaust]
   162 
   163 produces a rule which can be used to perform case distinction on both
   164 a list and a nat.
   165 
   166 * Quickcheck:
   167   - Quickcheck returns variable assignments as counterexamples, which
   168     allows to reveal the underspecification of functions under test.
   169     For example, refuting "hd xs = x", it presents the variable
   170     assignment xs = [] and x = a1 as a counterexample, assuming that
   171     any property is false whenever "hd []" occurs in it.
   172     These counterexample are marked as potentially spurious, as
   173     Quickcheck also returns "xs = []" as a counterexample to the
   174     obvious theorem "hd xs = hd xs".
   175     After finding a potentially spurious counterexample, Quickcheck
   176     continues searching for genuine ones.
   177     By default, Quickcheck shows potentially spurious and genuine
   178     counterexamples. The option "genuine_only" sets quickcheck to
   179     only show genuine counterexamples.
   180 
   181   - The command 'quickcheck_generator' creates random and exhaustive
   182     value generators for a given type and operations.
   183     It generates values by using the operations as if they were
   184     constructors of that type. 
   185   
   186 * Nitpick:
   187   - Fixed infinite loop caused by the 'peephole_optim' option and
   188     affecting 'rat' and 'real'.
   189 
   190 * Sledgehammer:
   191   - Added "lam_trans" and "minimize" options.
   192   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   193 
   194 * Metis:
   195   - Added possibility to specify lambda translations scheme as a
   196     parenthesized argument (e.g., "by (metis (lam_lifting) ...)").
   197 
   198 
   199 *** FOL ***
   200 
   201 * New "case_product" attribute (see HOL).
   202 
   203 
   204 *** ML ***
   205 
   206 * Antiquotation @{attributes [...]} embeds attribute source
   207 representation into the ML text, which is particularly useful with
   208 declarations like Local_Theory.note.
   209 
   210 * Structure Proof_Context follows standard naming scheme.  Old
   211 ProofContext has been discontinued.  INCOMPATIBILITY.
   212 
   213 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   214 change of semantics: update is applied to auxiliary local theory
   215 context as well.
   216 
   217 * Modernized some old-style infix operations:
   218 
   219   addeqcongs    ~> Simplifier.add_eqcong
   220   deleqcongs    ~> Simplifier.del_eqcong
   221   addcongs      ~> Simplifier.add_cong
   222   delcongs      ~> Simplifier.del_cong
   223   setmksimps    ~> Simplifier.set_mksimps
   224   setmkcong     ~> Simplifier.set_mkcong
   225   setmksym      ~> Simplifier.set_mksym
   226   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   227   settermless   ~> Simplifier.set_termless
   228   setsubgoaler  ~> Simplifier.set_subgoaler
   229   addsplits     ~> Splitter.add_split
   230   delsplits     ~> Splitter.del_split
   231 
   232 
   233 
   234 New in Isabelle2011-1 (October 2011)
   235 ------------------------------------
   236 
   237 *** General ***
   238 
   239 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   240 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   241 
   242   - Management of multiple theory files directly from the editor
   243     buffer store -- bypassing the file-system (no requirement to save
   244     files for checking).
   245 
   246   - Markup of formal entities within the text buffer, with semantic
   247     highlighting, tooltips and hyperlinks to jump to defining source
   248     positions.
   249 
   250   - Improved text rendering, with sub/superscripts in the source
   251     buffer (including support for copy/paste wrt. output panel, HTML
   252     theory output and other non-Isabelle text boxes).
   253 
   254   - Refined scheduling of proof checking and printing of results,
   255     based on interactive editor view.  (Note: jEdit folding and
   256     narrowing allows to restrict buffer perspectives explicitly.)
   257 
   258   - Reduced CPU performance requirements, usable on machines with few
   259     cores.
   260 
   261   - Reduced memory requirements due to pruning of unused document
   262     versions (garbage collection).
   263 
   264 See also ~~/src/Tools/jEdit/README.html for further information,
   265 including some remaining limitations.
   266 
   267 * Theory loader: source files are exclusively located via the master
   268 directory of each theory node (where the .thy file itself resides).
   269 The global load path (such as src/HOL/Library) has been discontinued.
   270 Note that the path element ~~ may be used to reference theories in the
   271 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   272 INCOMPATIBILITY.
   273 
   274 * Theory loader: source files are identified by content via SHA1
   275 digests.  Discontinued former path/modtime identification and optional
   276 ISABELLE_FILE_IDENT plugin scripts.
   277 
   278 * Parallelization of nested Isar proofs is subject to
   279 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   280 usedir option -Q.
   281 
   282 * Name space: former unsynchronized references are now proper
   283 configuration options, with more conventional names:
   284 
   285   long_names   ~> names_long
   286   short_names  ~> names_short
   287   unique_names ~> names_unique
   288 
   289 Minor INCOMPATIBILITY, need to declare options in context like this:
   290 
   291   declare [[names_unique = false]]
   292 
   293 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   294 that the result needs to be unique, which means fact specifications
   295 may have to be refined after enriching a proof context.
   296 
   297 * Attribute "case_names" has been refined: the assumptions in each case
   298 can be named now by following the case name with [name1 name2 ...].
   299 
   300 * Isabelle/Isar reference manual has been updated and extended:
   301   - "Synopsis" provides a catalog of main Isar language concepts.
   302   - Formal references in syntax diagrams, via @{rail} antiquotation.
   303   - Updated material from classic "ref" manual, notably about
   304     "Classical Reasoner".
   305 
   306 
   307 *** HOL ***
   308 
   309 * Class bot and top require underlying partial order rather than
   310 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   311 
   312 * Class complete_lattice: generalized a couple of lemmas from sets;
   313 generalized theorems INF_cong and SUP_cong.  New type classes for
   314 complete boolean algebras and complete linear orders.  Lemmas
   315 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   316 class complete_linorder.
   317 
   318 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   319 Sup_fun_def, Inf_apply, Sup_apply.
   320 
   321 Removed redundant lemmas (the right hand side gives hints how to
   322 replace them for (metis ...), or (simp only: ...) proofs):
   323 
   324   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   325   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   326   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   327   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   328   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   329   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   330   Inter_def ~> INF_def, image_def
   331   Union_def ~> SUP_def, image_def
   332   INT_eq ~> INF_def, and image_def
   333   UN_eq ~> SUP_def, and image_def
   334   INF_subset ~> INF_superset_mono [OF _ order_refl]
   335 
   336 More consistent and comprehensive names:
   337 
   338   INTER_eq_Inter_image ~> INF_def
   339   UNION_eq_Union_image ~> SUP_def
   340   INFI_def ~> INF_def
   341   SUPR_def ~> SUP_def
   342   INF_leI ~> INF_lower
   343   INF_leI2 ~> INF_lower2
   344   le_INFI ~> INF_greatest
   345   le_SUPI ~> SUP_upper
   346   le_SUPI2 ~> SUP_upper2
   347   SUP_leI ~> SUP_least
   348   INFI_bool_eq ~> INF_bool_eq
   349   SUPR_bool_eq ~> SUP_bool_eq
   350   INFI_apply ~> INF_apply
   351   SUPR_apply ~> SUP_apply
   352   INTER_def ~> INTER_eq
   353   UNION_def ~> UNION_eq
   354 
   355 INCOMPATIBILITY.
   356 
   357 * Renamed theory Complete_Lattice to Complete_Lattices.
   358 INCOMPATIBILITY.
   359 
   360 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   361 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   362 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   363 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   364 
   365 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   366 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   367 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   368 INCOMPATIBILITY.
   369 
   370 * Added syntactic classes "inf" and "sup" for the respective
   371 constants.  INCOMPATIBILITY: Changes in the argument order of the
   372 (mostly internal) locale predicates for some derived classes.
   373 
   374 * Theorem collections ball_simps and bex_simps do not contain theorems
   375 referring to UNION any longer; these have been moved to collection
   376 UN_ball_bex_simps.  INCOMPATIBILITY.
   377 
   378 * Theory Archimedean_Field: floor now is defined as parameter of a
   379 separate type class floor_ceiling.
   380 
   381 * Theory Finite_Set: more coherent development of fold_set locales:
   382 
   383     locale fun_left_comm ~> locale comp_fun_commute
   384     locale fun_left_comm_idem ~> locale comp_fun_idem
   385 
   386 Both use point-free characterization; interpretation proofs may need
   387 adjustment.  INCOMPATIBILITY.
   388 
   389 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   390 accordance with standard mathematical terminology. INCOMPATIBILITY.
   391 
   392 * Theory Complex_Main: The locale interpretations for the
   393 bounded_linear and bounded_bilinear locales have been removed, in
   394 order to reduce the number of duplicate lemmas. Users must use the
   395 original names for distributivity theorems, potential INCOMPATIBILITY.
   396 
   397   divide.add ~> add_divide_distrib
   398   divide.diff ~> diff_divide_distrib
   399   divide.setsum ~> setsum_divide_distrib
   400   mult.add_right ~> right_distrib
   401   mult.diff_right ~> right_diff_distrib
   402   mult_right.setsum ~> setsum_right_distrib
   403   mult_left.diff ~> left_diff_distrib
   404 
   405 * Theory Complex_Main: Several redundant theorems have been removed or
   406 replaced by more general versions. INCOMPATIBILITY.
   407 
   408   real_diff_def ~> minus_real_def
   409   real_divide_def ~> divide_real_def
   410   real_less_def ~> less_le
   411   real_abs_def ~> abs_real_def
   412   real_sgn_def ~> sgn_real_def
   413   real_mult_commute ~> mult_commute
   414   real_mult_assoc ~> mult_assoc
   415   real_mult_1 ~> mult_1_left
   416   real_add_mult_distrib ~> left_distrib
   417   real_zero_not_eq_one ~> zero_neq_one
   418   real_mult_inverse_left ~> left_inverse
   419   INVERSE_ZERO ~> inverse_zero
   420   real_le_refl ~> order_refl
   421   real_le_antisym ~> order_antisym
   422   real_le_trans ~> order_trans
   423   real_le_linear ~> linear
   424   real_le_eq_diff ~> le_iff_diff_le_0
   425   real_add_left_mono ~> add_left_mono
   426   real_mult_order ~> mult_pos_pos
   427   real_mult_less_mono2 ~> mult_strict_left_mono
   428   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   429   real_0_le_divide_iff ~> zero_le_divide_iff
   430   realpow_two_disj ~> power2_eq_iff
   431   real_squared_diff_one_factored ~> square_diff_one_factored
   432   realpow_two_diff ~> square_diff_square_factored
   433   reals_complete2 ~> complete_real
   434   real_sum_squared_expand ~> power2_sum
   435   exp_ln_eq ~> ln_unique
   436   expi_add ~> exp_add
   437   expi_zero ~> exp_zero
   438   lemma_DERIV_subst ~> DERIV_cong
   439   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   440   LIMSEQ_const ~> tendsto_const
   441   LIMSEQ_norm ~> tendsto_norm
   442   LIMSEQ_add ~> tendsto_add
   443   LIMSEQ_minus ~> tendsto_minus
   444   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   445   LIMSEQ_diff ~> tendsto_diff
   446   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   447   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   448   LIMSEQ_mult ~> tendsto_mult
   449   LIMSEQ_inverse ~> tendsto_inverse
   450   LIMSEQ_divide ~> tendsto_divide
   451   LIMSEQ_pow ~> tendsto_power
   452   LIMSEQ_setsum ~> tendsto_setsum
   453   LIMSEQ_setprod ~> tendsto_setprod
   454   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   455   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   456   LIMSEQ_imp_rabs ~> tendsto_rabs
   457   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   458   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   459   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   460   LIMSEQ_Complex ~> tendsto_Complex
   461   LIM_ident ~> tendsto_ident_at
   462   LIM_const ~> tendsto_const
   463   LIM_add ~> tendsto_add
   464   LIM_add_zero ~> tendsto_add_zero
   465   LIM_minus ~> tendsto_minus
   466   LIM_diff ~> tendsto_diff
   467   LIM_norm ~> tendsto_norm
   468   LIM_norm_zero ~> tendsto_norm_zero
   469   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   470   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   471   LIM_rabs ~> tendsto_rabs
   472   LIM_rabs_zero ~> tendsto_rabs_zero
   473   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   474   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   475   LIM_compose ~> tendsto_compose
   476   LIM_mult ~> tendsto_mult
   477   LIM_scaleR ~> tendsto_scaleR
   478   LIM_of_real ~> tendsto_of_real
   479   LIM_power ~> tendsto_power
   480   LIM_inverse ~> tendsto_inverse
   481   LIM_sgn ~> tendsto_sgn
   482   isCont_LIM_compose ~> isCont_tendsto_compose
   483   bounded_linear.LIM ~> bounded_linear.tendsto
   484   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   485   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   486   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   487   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   488   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   489   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   490 
   491 * Theory Complex_Main: The definition of infinite series was
   492 generalized.  Now it is defined on the type class {topological_space,
   493 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   494 
   495 * Theory Complex_Main: The complex exponential function "expi" is now
   496 a type-constrained abbreviation for "exp :: complex => complex"; thus
   497 several polymorphic lemmas about "exp" are now applicable to "expi".
   498 
   499 * Code generation:
   500 
   501   - Theory Library/Code_Char_ord provides native ordering of
   502     characters in the target language.
   503 
   504   - Commands code_module and code_library are legacy, use export_code
   505     instead.
   506 
   507   - Method "evaluation" is legacy, use method "eval" instead.
   508 
   509   - Legacy evaluator "SML" is deactivated by default.  May be
   510     reactivated by the following theory command:
   511 
   512       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   513 
   514 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   515 
   516 * New proof method "induction" that gives induction hypotheses the
   517 name "IH", thus distinguishing them from further hypotheses that come
   518 from rule induction.  The latter are still called "hyps".  Method
   519 "induction" is a thin wrapper around "induct" and follows the same
   520 syntax.
   521 
   522 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
   523 still available as a legacy feature for some time.
   524 
   525 * Nitpick:
   526   - Added "need" and "total_consts" options.
   527   - Reintroduced "show_skolems" option by popular demand.
   528   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   529     INCOMPATIBILITY.
   530 
   531 * Sledgehammer:
   532   - Use quasi-sound (and efficient) translations by default.
   533   - Added support for the following provers: E-ToFoF, LEO-II,
   534     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
   535   - Automatically preplay and minimize proofs before showing them if
   536     this can be done within reasonable time.
   537   - sledgehammer available_provers ~> sledgehammer supported_provers.
   538     INCOMPATIBILITY.
   539   - Added "preplay_timeout", "slicing", "type_enc", "sound",
   540     "max_mono_iters", and "max_new_mono_instances" options.
   541   - Removed "explicit_apply" and "full_types" options as well as "Full
   542     Types" Proof General menu item. INCOMPATIBILITY.
   543 
   544 * Metis:
   545   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   546   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
   547     INCOMPATIBILITY.
   548 
   549 * Command 'try':
   550   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
   551     "elim:" options. INCOMPATIBILITY.
   552   - Introduced 'try' that not only runs 'try_methods' but also
   553     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
   554 
   555 * Quickcheck:
   556   - Added "eval" option to evaluate terms for the found counterexample
   557     (currently only supported by the default (exhaustive) tester).
   558   - Added post-processing of terms to obtain readable counterexamples
   559     (currently only supported by the default (exhaustive) tester).
   560   - New counterexample generator quickcheck[narrowing] enables
   561     narrowing-based testing.  Requires the Glasgow Haskell compiler
   562     with its installation location defined in the Isabelle settings
   563     environment as ISABELLE_GHC.
   564   - Removed quickcheck tester "SML" based on the SML code generator
   565     (formly in HOL/Library).
   566 
   567 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
   568 use 'partial_function' instead.
   569 
   570 * Theory Library/Extended_Reals replaces now the positive extended
   571 reals found in probability theory. This file is extended by
   572 Multivariate_Analysis/Extended_Real_Limits.
   573 
   574 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
   575 from where it must be imported explicitly if it is really required.
   576 INCOMPATIBILITY.
   577 
   578 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
   579 been moved here.  INCOMPATIBILITY.
   580 
   581 * Theory Library/Saturated provides type of numbers with saturated
   582 arithmetic.
   583 
   584 * Theory Library/Product_Lattice defines a pointwise ordering for the
   585 product type 'a * 'b, and provides instance proofs for various order
   586 and lattice type classes.
   587 
   588 * Theory Library/Countable now provides the "countable_datatype" proof
   589 method for proving "countable" class instances for datatypes.
   590 
   591 * Theory Library/Cset_Monad allows do notation for computable sets
   592 (cset) via the generic monad ad-hoc overloading facility.
   593 
   594 * Library: Theories of common data structures are split into theories
   595 for implementation, an invariant-ensuring type, and connection to an
   596 abstract type. INCOMPATIBILITY.
   597 
   598   - RBT is split into RBT and RBT_Mapping.
   599   - AssocList is split and renamed into AList and AList_Mapping.
   600   - DList is split into DList_Impl, DList, and DList_Cset.
   601   - Cset is split into Cset and List_Cset.
   602 
   603 * Theory Library/Nat_Infinity has been renamed to
   604 Library/Extended_Nat, with name changes of the following types and
   605 constants:
   606 
   607   type inat   ~> type enat
   608   Fin         ~> enat
   609   Infty       ~> infinity (overloaded)
   610   iSuc        ~> eSuc
   611   the_Fin     ~> the_enat
   612 
   613 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   614 been renamed accordingly. INCOMPATIBILITY.
   615 
   616 * Session Multivariate_Analysis: The euclidean_space type class now
   617 fixes a constant "Basis :: 'a set" consisting of the standard
   618 orthonormal basis for the type. Users now have the option of
   619 quantifying over this set instead of using the "basis" function, e.g.
   620 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
   621 
   622 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   623 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   624 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   625 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   626 changed to match. Definition theorems for overloaded constants now use
   627 the standard "foo_vec_def" naming scheme. A few other theorems have
   628 been renamed as follows (INCOMPATIBILITY):
   629 
   630   Cart_eq          ~> vec_eq_iff
   631   dist_nth_le_cart ~> dist_vec_nth_le
   632   tendsto_vector   ~> vec_tendstoI
   633   Cauchy_vector    ~> vec_CauchyI
   634 
   635 * Session Multivariate_Analysis: Several duplicate theorems have been
   636 removed, and other theorems have been renamed or replaced with more
   637 general versions. INCOMPATIBILITY.
   638 
   639   finite_choice ~> finite_set_choice
   640   eventually_conjI ~> eventually_conj
   641   eventually_and ~> eventually_conj_iff
   642   eventually_false ~> eventually_False
   643   setsum_norm ~> norm_setsum
   644   Lim_sequentially ~> LIMSEQ_def
   645   Lim_ident_at ~> LIM_ident
   646   Lim_const ~> tendsto_const
   647   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   648   Lim_neg ~> tendsto_minus
   649   Lim_add ~> tendsto_add
   650   Lim_sub ~> tendsto_diff
   651   Lim_mul ~> tendsto_scaleR
   652   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   653   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   654   Lim_linear ~> bounded_linear.tendsto
   655   Lim_component ~> tendsto_euclidean_component
   656   Lim_component_cart ~> tendsto_vec_nth
   657   Lim_inner ~> tendsto_inner [OF tendsto_const]
   658   dot_lsum ~> inner_setsum_left
   659   dot_rsum ~> inner_setsum_right
   660   continuous_cmul ~> continuous_scaleR [OF continuous_const]
   661   continuous_neg ~> continuous_minus
   662   continuous_sub ~> continuous_diff
   663   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
   664   continuous_mul ~> continuous_scaleR
   665   continuous_inv ~> continuous_inverse
   666   continuous_at_within_inv ~> continuous_at_within_inverse
   667   continuous_at_inv ~> continuous_at_inverse
   668   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
   669   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
   670   continuous_at_component ~> continuous_component [OF continuous_at_id]
   671   continuous_on_neg ~> continuous_on_minus
   672   continuous_on_sub ~> continuous_on_diff
   673   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   674   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   675   continuous_on_mul ~> continuous_on_scaleR
   676   continuous_on_mul_real ~> continuous_on_mult
   677   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   678   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
   679   continuous_on_inverse ~> continuous_on_inv
   680   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
   681   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
   682   subset_interior ~> interior_mono
   683   subset_closure ~> closure_mono
   684   closure_univ ~> closure_UNIV
   685   real_arch_lt ~> reals_Archimedean2
   686   real_arch ~> reals_Archimedean3
   687   real_abs_norm ~> abs_norm_cancel
   688   real_abs_sub_norm ~> norm_triangle_ineq3
   689   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
   690 
   691 * Session HOL-Probability:
   692   - Caratheodory's extension lemma is now proved for ring_of_sets.
   693   - Infinite products of probability measures are now available.
   694   - Sigma closure is independent, if the generator is independent
   695   - Use extended reals instead of positive extended
   696     reals. INCOMPATIBILITY.
   697 
   698 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
   699 
   700   expand_fun_below ~> fun_below_iff
   701   below_fun_ext ~> fun_belowI
   702   expand_cfun_eq ~> cfun_eq_iff
   703   ext_cfun ~> cfun_eqI
   704   expand_cfun_below ~> cfun_below_iff
   705   below_cfun_ext ~> cfun_belowI
   706   monofun_fun_fun ~> fun_belowD
   707   monofun_fun_arg ~> monofunE
   708   monofun_lub_fun ~> adm_monofun [THEN admD]
   709   cont_lub_fun ~> adm_cont [THEN admD]
   710   cont2cont_Rep_CFun ~> cont2cont_APP
   711   cont_Rep_CFun_app ~> cont_APP_app
   712   cont_Rep_CFun_app_app ~> cont_APP_app_app
   713   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
   714   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
   715   contlub_cfun ~> lub_APP [symmetric]
   716   contlub_LAM ~> lub_LAM [symmetric]
   717   thelubI ~> lub_eqI
   718   UU_I ~> bottomI
   719   lift_distinct1 ~> lift.distinct(1)
   720   lift_distinct2 ~> lift.distinct(2)
   721   Def_not_UU ~> lift.distinct(2)
   722   Def_inject ~> lift.inject
   723   below_UU_iff ~> below_bottom_iff
   724   eq_UU_iff ~> eq_bottom_iff
   725 
   726 
   727 *** Document preparation ***
   728 
   729 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   730 isar-ref manual, both for description and actual application of the
   731 same.
   732 
   733 * Antiquotation @{value} evaluates the given term and presents its
   734 result.
   735 
   736 * Antiquotations: term style "isub" provides ad-hoc conversion of
   737 variables x1, y23 into subscripted form x\<^isub>1,
   738 y\<^isub>2\<^isub>3.
   739 
   740 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   741 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   742 
   743 * Localized \isabellestyle switch can be used within blocks or groups
   744 like this:
   745 
   746   \isabellestyle{it}  %preferred default
   747   {\isabellestylett @{text "typewriter stuff"}}
   748 
   749 * Discontinued special treatment of hard tabulators.  Implicit
   750 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
   751 layouts.
   752 
   753 
   754 *** ML ***
   755 
   756 * The inner syntax of sort/type/term/prop supports inlined YXML
   757 representations within quoted string tokens.  By encoding logical
   758 entities via Term_XML (in ML or Scala) concrete syntax can be
   759 bypassed, which is particularly useful for producing bits of text
   760 under external program control.
   761 
   762 * Antiquotations for ML and document preparation are managed as theory
   763 data, which requires explicit setup.
   764 
   765 * Isabelle_Process.is_active allows tools to check if the official
   766 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   767 (better known as Proof General).
   768 
   769 * Structure Proof_Context follows standard naming scheme.  Old
   770 ProofContext is still available for some time as legacy alias.
   771 
   772 * Structure Timing provides various operations for timing; supersedes
   773 former start_timing/end_timing etc.
   774 
   775 * Path.print is the official way to show file-system paths to users
   776 (including quotes etc.).
   777 
   778 * Inner syntax: identifiers in parse trees of generic categories
   779 "logic", "aprop", "idt" etc. carry position information (disguised as
   780 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   781 translations that choke on unexpected type constraints.  Positions can
   782 be stripped in ML translations via Syntax.strip_positions /
   783 Syntax.strip_positions_ast, or via the syntax constant
   784 "_strip_positions" within parse trees.  As last resort, positions can
   785 be disabled via the configuration option Syntax.positions, which is
   786 called "syntax_positions" in Isar attribute syntax.
   787 
   788 * Discontinued special status of various ML structures that contribute
   789 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   790 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   791 refer directly to Ast.Constant, Lexicon.is_identifier,
   792 Syntax_Trans.mk_binder_tr etc.
   793 
   794 * Typed print translation: discontinued show_sorts argument, which is
   795 already available via context of "advanced" translation.
   796 
   797 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   798 goal states; body tactic needs to address all subgoals uniformly.
   799 
   800 * Slightly more special eq_list/eq_set, with shortcut involving
   801 pointer equality (assumes that eq relation is reflexive).
   802 
   803 * Classical tactics use proper Proof.context instead of historic types
   804 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   805 operate directly on Proof.context.  Raw type claset retains its use as
   806 snapshot of the classical context, which can be recovered via
   807 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   808 INCOMPATIBILITY, classical tactics and derived proof methods require
   809 proper Proof.context.
   810 
   811 
   812 *** System ***
   813 
   814 * Discontinued support for Poly/ML 5.2, which was the last version
   815 without proper multithreading and TimeLimit implementation.
   816 
   817 * Discontinued old lib/scripts/polyml-platform, which has been
   818 obsolete since Isabelle2009-2.
   819 
   820 * Various optional external tools are referenced more robustly and
   821 uniformly by explicit Isabelle settings as follows:
   822 
   823   ISABELLE_CSDP   (formerly CSDP_EXE)
   824   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
   825   ISABELLE_OCAML  (formerly EXEC_OCAML)
   826   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
   827   ISABELLE_YAP    (formerly EXEC_YAP)
   828 
   829 Note that automated detection from the file-system or search path has
   830 been discontinued.  INCOMPATIBILITY.
   831 
   832 * Scala layer provides JVM method invocation service for static
   833 methods of type (String)String, see Invoke_Scala.method in ML.  For
   834 example:
   835 
   836   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   837 
   838 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
   839 this allows to pass structured values between ML and Scala.
   840 
   841 * The IsabelleText fonts includes some further glyphs to support the
   842 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
   843 installed a local copy (which is normally *not* required) need to
   844 delete or update it from ~~/lib/fonts/.
   845 
   846 
   847 
   848 New in Isabelle2011 (January 2011)
   849 ----------------------------------
   850 
   851 *** General ***
   852 
   853 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   854 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   855 useful tooltips and hyperlinks produced from its static analysis.  The
   856 bundled component provides an executable Isabelle tool that can be run
   857 like this:
   858 
   859   Isabelle2011/bin/isabelle jedit
   860 
   861 * Significantly improved Isabelle/Isar implementation manual.
   862 
   863 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   864 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   865 while the default heap location within that directory lacks that extra
   866 suffix.  This isolates multiple Isabelle installations from each
   867 other, avoiding problems with old settings in new versions.
   868 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   869 
   870 * Source files are always encoded as UTF-8, instead of old-fashioned
   871 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   872 the following package declarations:
   873 
   874   \usepackage[utf8]{inputenc}
   875   \usepackage{textcomp}
   876 
   877 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   878 a Unicode character is treated as a single symbol, not a sequence of
   879 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   880 contain symbols without further backslash escapes, Unicode can now be
   881 used here as well.  Recall that Symbol.explode in ML provides a
   882 consistent view on symbols, while raw explode (or String.explode)
   883 merely give a byte-oriented representation.
   884 
   885 * Theory loader: source files are primarily located via the master
   886 directory of each theory node (where the .thy file itself resides).
   887 The global load path is still partially available as legacy feature.
   888 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   889 explicit paths, relatively to the theory.
   890 
   891 * Special treatment of ML file names has been discontinued.
   892 Historically, optional extensions .ML or .sml were added on demand --
   893 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   894 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   895 
   896 * Various options that affect pretty printing etc. are now properly
   897 handled within the context via configuration options, instead of
   898 unsynchronized references or print modes.  There are both ML Config.T
   899 entities and Isar declaration attributes to access these.
   900 
   901   ML (Config.T)                 Isar (attribute)
   902 
   903   eta_contract                  eta_contract
   904   show_brackets                 show_brackets
   905   show_sorts                    show_sorts
   906   show_types                    show_types
   907   show_question_marks           show_question_marks
   908   show_consts                   show_consts
   909   show_abbrevs                  show_abbrevs
   910 
   911   Syntax.ast_trace              syntax_ast_trace
   912   Syntax.ast_stat               syntax_ast_stat
   913   Syntax.ambiguity_level        syntax_ambiguity_level
   914 
   915   Goal_Display.goals_limit      goals_limit
   916   Goal_Display.show_main_goal   show_main_goal
   917 
   918   Method.rule_trace             rule_trace
   919 
   920   Thy_Output.display            thy_output_display
   921   Thy_Output.quotes             thy_output_quotes
   922   Thy_Output.indent             thy_output_indent
   923   Thy_Output.source             thy_output_source
   924   Thy_Output.break              thy_output_break
   925 
   926 Note that corresponding "..._default" references in ML may only be
   927 changed globally at the ROOT session setup, but *not* within a theory.
   928 The option "show_abbrevs" supersedes the former print mode
   929 "no_abbrevs" with inverted meaning.
   930 
   931 * More systematic naming of some configuration options.
   932 INCOMPATIBILITY.
   933 
   934   trace_simp  ~>  simp_trace
   935   debug_simp  ~>  simp_debug
   936 
   937 * Support for real valued configuration options, using simplistic
   938 floating-point notation that coincides with the inner syntax for
   939 float_token.
   940 
   941 * Support for real valued preferences (with approximative PGIP type):
   942 front-ends need to accept "pgint" values in float notation.
   943 INCOMPATIBILITY.
   944 
   945 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   946 DejaVu Sans.
   947 
   948 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   949 
   950 
   951 *** Pure ***
   952 
   953 * Command 'type_synonym' (with single argument) replaces somewhat
   954 outdated 'types', which is still available as legacy feature for some
   955 time.
   956 
   957 * Command 'nonterminal' (with 'and' separated list of arguments)
   958 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   959 
   960 * Command 'notepad' replaces former 'example_proof' for
   961 experimentation in Isar without any result.  INCOMPATIBILITY.
   962 
   963 * Locale interpretation commands 'interpret' and 'sublocale' accept
   964 lists of equations to map definitions in a locale to appropriate
   965 entities in the context of the interpretation.  The 'interpretation'
   966 command already provided this functionality.
   967 
   968 * Diagnostic command 'print_dependencies' prints the locale instances
   969 that would be activated if the specified expression was interpreted in
   970 the current context.  Variant "print_dependencies!" assumes a context
   971 without interpretations.
   972 
   973 * Diagnostic command 'print_interps' prints interpretations in proofs
   974 in addition to interpretations in theories.
   975 
   976 * Discontinued obsolete 'global' and 'local' commands to manipulate
   977 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   978 Sign.root_path and Sign.local_path may be applied directly where this
   979 feature is still required for historical reasons.
   980 
   981 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   982 'definition' instead.
   983 
   984 * The "prems" fact, which refers to the accidental collection of
   985 foundational premises in the context, is now explicitly marked as
   986 legacy feature and will be discontinued soon.  Consider using "assms"
   987 of the head statement or reference facts by explicit names.
   988 
   989 * Document antiquotations @{class} and @{type} print classes and type
   990 constructors.
   991 
   992 * Document antiquotation @{file} checks file/directory entries within
   993 the local file system.
   994 
   995 
   996 *** HOL ***
   997 
   998 * Coercive subtyping: functions can be declared as coercions and type
   999 inference will add them as necessary upon input of a term.  Theory
  1000 Complex_Main declares real :: nat => real and real :: int => real as
  1001 coercions. A coercion function f is declared like this:
  1002 
  1003   declare [[coercion f]]
  1004 
  1005 To lift coercions through type constructors (e.g. from nat => real to
  1006 nat list => real list), map functions can be declared, e.g.
  1007 
  1008   declare [[coercion_map map]]
  1009 
  1010 Currently coercion inference is activated only in theories including
  1011 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1012 the configuration option "coercion_enabled", e.g. it can be enabled in
  1013 other theories like this:
  1014 
  1015   declare [[coercion_enabled]]
  1016 
  1017 * Command 'partial_function' provides basic support for recursive
  1018 function definitions over complete partial orders.  Concrete instances
  1019 are provided for i) the option type, ii) tail recursion on arbitrary
  1020 types, and iii) the heap monad of Imperative_HOL.  See
  1021 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1022 for examples.
  1023 
  1024 * Function package: f.psimps rules are no longer implicitly declared
  1025 as [simp].  INCOMPATIBILITY.
  1026 
  1027 * Datatype package: theorems generated for executable equality (class
  1028 "eq") carry proper names and are treated as default code equations.
  1029 
  1030 * Inductive package: now offers command 'inductive_simps' to
  1031 automatically derive instantiated and simplified equations for
  1032 inductive predicates, similar to 'inductive_cases'.
  1033 
  1034 * Command 'enriched_type' allows to register properties of the
  1035 functorial structure of types.
  1036 
  1037 * Improved infrastructure for term evaluation using code generator
  1038 techniques, in particular static evaluation conversions.
  1039 
  1040 * Code generator: Scala (2.8 or higher) has been added to the target
  1041 languages.
  1042 
  1043 * Code generator: globbing constant expressions "*" and "Theory.*"
  1044 have been replaced by the more idiomatic "_" and "Theory._".
  1045 INCOMPATIBILITY.
  1046 
  1047 * Code generator: export_code without explicit file declaration prints
  1048 to standard output.  INCOMPATIBILITY.
  1049 
  1050 * Code generator: do not print function definitions for case
  1051 combinators any longer.
  1052 
  1053 * Code generator: simplification with rules determined with
  1054 src/Tools/Code/code_simp.ML and method "code_simp".
  1055 
  1056 * Code generator for records: more idiomatic representation of record
  1057 types.  Warning: records are not covered by ancient SML code
  1058 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1059 rep_datatype declaration helps to succeed then:
  1060 
  1061   record 'a foo = ...
  1062   ...
  1063   rep_datatype foo_ext ...
  1064 
  1065 * Records: logical foundation type for records does not carry a
  1066 '_type' suffix any longer (obsolete due to authentic syntax).
  1067 INCOMPATIBILITY.
  1068 
  1069 * Quickcheck now by default uses exhaustive testing instead of random
  1070 testing.  Random testing can be invoked by "quickcheck [random]",
  1071 exhaustive testing by "quickcheck [exhaustive]".
  1072 
  1073 * Quickcheck instantiates polymorphic types with small finite
  1074 datatypes by default. This enables a simple execution mechanism to
  1075 handle quantifiers and function equality over the finite datatypes.
  1076 
  1077 * Quickcheck random generator has been renamed from "code" to
  1078 "random".  INCOMPATIBILITY.
  1079 
  1080 * Quickcheck now has a configurable time limit which is set to 30
  1081 seconds by default. This can be changed by adding [timeout = n] to the
  1082 quickcheck command. The time limit for Auto Quickcheck is still set
  1083 independently.
  1084 
  1085 * Quickcheck in locales considers interpretations of that locale for
  1086 counter example search.
  1087 
  1088 * Sledgehammer:
  1089   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1090     method. See the Sledgehammer manual for details ("isabelle doc
  1091     sledgehammer").
  1092   - Renamed commands:
  1093     sledgehammer atp_info ~> sledgehammer running_provers
  1094     sledgehammer atp_kill ~> sledgehammer kill_provers
  1095     sledgehammer available_atps ~> sledgehammer available_provers
  1096     INCOMPATIBILITY.
  1097   - Renamed options:
  1098     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1099     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1100     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1101     (and "ms" and "min" are no longer supported)
  1102     INCOMPATIBILITY.
  1103 
  1104 * Nitpick:
  1105   - Renamed options:
  1106     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1107     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1108     INCOMPATIBILITY.
  1109   - Added support for partial quotient types.
  1110   - Added local versions of the "Nitpick.register_xxx" functions.
  1111   - Added "whack" option.
  1112   - Allow registration of quotient types as codatatypes.
  1113   - Improved "merge_type_vars" option to merge more types.
  1114   - Removed unsound "fast_descrs" option.
  1115   - Added custom symmetry breaking for datatypes, making it possible to reach
  1116     higher cardinalities.
  1117   - Prevent the expansion of too large definitions.
  1118 
  1119 * Proof methods "metis" and "meson" now have configuration options
  1120 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1121 to diagnose these tools. E.g.
  1122 
  1123     using [[metis_trace = true]]
  1124 
  1125 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1126 manually as command 'solve_direct'.
  1127 
  1128 * The default SMT solver Z3 must be enabled explicitly (due to
  1129 licensing issues) by setting the environment variable
  1130 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1131 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1132 changing the SMT solver is done via the configuration option
  1133 "smt_solver".
  1134 
  1135 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1136 i.e. "remote_cvc3" and "remote_z3".
  1137 
  1138 * Added basic SMT support for datatypes, records, and typedefs using
  1139 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1140 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1141 support for a similar behavior).  Minor INCOMPATIBILITY.
  1142 
  1143 * Changed SMT configuration options:
  1144   - Renamed:
  1145     z3_proofs ~> smt_oracle (with inverted meaning)
  1146     z3_trace_assms ~> smt_trace_used_facts
  1147     INCOMPATIBILITY.
  1148   - Added:
  1149     smt_verbose
  1150     smt_random_seed
  1151     smt_datatypes
  1152     smt_infer_triggers
  1153     smt_monomorph_limit
  1154     cvc3_options
  1155     remote_cvc3_options
  1156     remote_z3_options
  1157     yices_options
  1158 
  1159 * Boogie output files (.b2i files) need to be declared in the theory
  1160 header.
  1161 
  1162 * Simplification procedure "list_to_set_comprehension" rewrites list
  1163 comprehensions applied to List.set to set comprehensions.  Occasional
  1164 INCOMPATIBILITY, may be deactivated like this:
  1165 
  1166   declare [[simproc del: list_to_set_comprehension]]
  1167 
  1168 * Removed old version of primrec package.  INCOMPATIBILITY.
  1169 
  1170 * Removed simplifier congruence rule of "prod_case", as has for long
  1171 been the case with "split".  INCOMPATIBILITY.
  1172 
  1173 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1174 
  1175 * Removed [split_format ... and ... and ...] version of
  1176 [split_format].  Potential INCOMPATIBILITY.
  1177 
  1178 * Predicate "sorted" now defined inductively, with nice induction
  1179 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1180 
  1181 * Constant "contents" renamed to "the_elem", to free the generic name
  1182 contents for other uses.  INCOMPATIBILITY.
  1183 
  1184 * Renamed class eq and constant eq (for code generation) to class
  1185 equal and constant equal, plus renaming of related facts and various
  1186 tuning.  INCOMPATIBILITY.
  1187 
  1188 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1189 
  1190 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1191 INCOMPATIBILITY.
  1192 
  1193 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1194 avoid confusion with finite sets.  INCOMPATIBILITY.
  1195 
  1196 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1197 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1198 for congruent(2)).
  1199 
  1200 * Some previously unqualified names have been qualified:
  1201 
  1202   types
  1203     bool ~> HOL.bool
  1204     nat ~> Nat.nat
  1205 
  1206   constants
  1207     Trueprop ~> HOL.Trueprop
  1208     True ~> HOL.True
  1209     False ~> HOL.False
  1210     op & ~> HOL.conj
  1211     op | ~> HOL.disj
  1212     op --> ~> HOL.implies
  1213     op = ~> HOL.eq
  1214     Not ~> HOL.Not
  1215     The ~> HOL.The
  1216     All ~> HOL.All
  1217     Ex ~> HOL.Ex
  1218     Ex1 ~> HOL.Ex1
  1219     Let ~> HOL.Let
  1220     If ~> HOL.If
  1221     Ball ~> Set.Ball
  1222     Bex ~> Set.Bex
  1223     Suc ~> Nat.Suc
  1224     Pair ~> Product_Type.Pair
  1225     fst ~> Product_Type.fst
  1226     snd ~> Product_Type.snd
  1227     curry ~> Product_Type.curry
  1228     op : ~> Set.member
  1229     Collect ~> Set.Collect
  1230 
  1231 INCOMPATIBILITY.
  1232 
  1233 * More canonical naming convention for some fundamental definitions:
  1234 
  1235     bot_bool_eq ~> bot_bool_def
  1236     top_bool_eq ~> top_bool_def
  1237     inf_bool_eq ~> inf_bool_def
  1238     sup_bool_eq ~> sup_bool_def
  1239     bot_fun_eq  ~> bot_fun_def
  1240     top_fun_eq  ~> top_fun_def
  1241     inf_fun_eq  ~> inf_fun_def
  1242     sup_fun_eq  ~> sup_fun_def
  1243 
  1244 INCOMPATIBILITY.
  1245 
  1246 * More stylized fact names:
  1247 
  1248   expand_fun_eq ~> fun_eq_iff
  1249   expand_set_eq ~> set_eq_iff
  1250   set_ext       ~> set_eqI
  1251   nat_number    ~> eval_nat_numeral
  1252 
  1253 INCOMPATIBILITY.
  1254 
  1255 * Refactoring of code-generation specific operations in theory List:
  1256 
  1257   constants
  1258     null ~> List.null
  1259 
  1260   facts
  1261     mem_iff ~> member_def
  1262     null_empty ~> null_def
  1263 
  1264 INCOMPATIBILITY.  Note that these were not supposed to be used
  1265 regularly unless for striking reasons; their main purpose was code
  1266 generation.
  1267 
  1268 Various operations from the Haskell prelude are used for generating
  1269 Haskell code.
  1270 
  1271 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1272 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1273 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1274 
  1275 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1276 "*" and "+" respectively.  INCOMPATIBILITY.
  1277 
  1278 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1279 "Sum_Type.Plus" instead.
  1280 
  1281 * Constant "split" has been merged with constant "prod_case"; names of
  1282 ML functions, facts etc. involving split have been retained so far,
  1283 though.  INCOMPATIBILITY.
  1284 
  1285 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1286 instead.  INCOMPATIBILITY.
  1287 
  1288 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1289 INCOMPATIBILITY.
  1290 
  1291 * Former theory Library/Enum is now part of the HOL-Main image.
  1292 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1293 referred to by its qualified name.
  1294 
  1295   enum    ~>  Enum.enum
  1296   nlists  ~>  Enum.nlists
  1297   product ~>  Enum.product
  1298 
  1299 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1300 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1301 INCOMPATIBILITY.
  1302 
  1303 * Theory Library/SetsAndFunctions has been split into
  1304 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1305 for instance definitions for functions; various improvements.
  1306 INCOMPATIBILITY.
  1307 
  1308 * Theory Library/Multiset provides stable quicksort implementation of
  1309 sort_key.
  1310 
  1311 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1312 INCOMPATIBILITY.
  1313 
  1314 * Session Multivariate_Analysis: introduced a type class for euclidean
  1315 space.  Most theorems are now stated in terms of euclidean spaces
  1316 instead of finite cartesian products.
  1317 
  1318   types
  1319     real ^ 'n ~>  'a::real_vector
  1320               ~>  'a::euclidean_space
  1321               ~>  'a::ordered_euclidean_space
  1322         (depends on your needs)
  1323 
  1324   constants
  1325      _ $ _        ~> _ $$ _
  1326      \<chi> x. _  ~> \<chi>\<chi> x. _
  1327      CARD('n)     ~> DIM('a)
  1328 
  1329 Also note that the indices are now natural numbers and not from some
  1330 finite type. Finite cartesian products of euclidean spaces, products
  1331 of euclidean spaces the real and complex numbers are instantiated to
  1332 be euclidean_spaces.  INCOMPATIBILITY.
  1333 
  1334 * Session Probability: introduced pextreal as positive extended real
  1335 numbers.  Use pextreal as value for measures.  Introduce the
  1336 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1337 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1338 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1339 
  1340 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1341 INCOMPATIBILITY.
  1342 
  1343 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1344 prove verification conditions generated by the SPARK Ada program
  1345 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1346 
  1347 
  1348 *** HOL-Algebra ***
  1349 
  1350 * Theorems for additive ring operations (locale abelian_monoid and
  1351 descendants) are generated by interpretation from their multiplicative
  1352 counterparts.  Names (in particular theorem names) have the mandatory
  1353 qualifier 'add'.  Previous theorem names are redeclared for
  1354 compatibility.
  1355 
  1356 * Structure "int_ring" is now an abbreviation (previously a
  1357 definition).  This fits more natural with advanced interpretations.
  1358 
  1359 
  1360 *** HOLCF ***
  1361 
  1362 * The domain package now runs in definitional mode by default: The
  1363 former command 'new_domain' is now called 'domain'.  To use the domain
  1364 package in its original axiomatic mode, use 'domain (unsafe)'.
  1365 INCOMPATIBILITY.
  1366 
  1367 * The new class "domain" is now the default sort.  Class "predomain"
  1368 is an unpointed version of "domain". Theories can be updated by
  1369 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1370 
  1371   'a::type ~> 'a::countable
  1372   'a::cpo  ~> 'a::predomain
  1373   'a::pcpo ~> 'a::domain
  1374 
  1375 * The old type class "rep" has been superseded by class "domain".
  1376 Accordingly, users of the definitional package must remove any
  1377 "default_sort rep" declarations.  INCOMPATIBILITY.
  1378 
  1379 * The domain package (definitional mode) now supports unpointed
  1380 predomain argument types, as long as they are marked 'lazy'. (Strict
  1381 arguments must be in class "domain".) For example, the following
  1382 domain definition now works:
  1383 
  1384   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1385 
  1386 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1387 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1388 'a option, and 'a list.  Additionally, it configures fixrec and the
  1389 domain package to work with these types.  For example:
  1390 
  1391   fixrec isInl :: "('a + 'b) u -> tr"
  1392     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1393 
  1394   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1395 
  1396 * The "(permissive)" option of fixrec has been replaced with a
  1397 per-equation "(unchecked)" option. See
  1398 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1399 
  1400 * The "bifinite" class no longer fixes a constant "approx"; the class
  1401 now just asserts that such a function exists.  INCOMPATIBILITY.
  1402 
  1403 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1404 defines an embedding of type 'a defl into udom by default; instances
  1405 of "bifinite" and "domain" classes are available in
  1406 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1407 
  1408 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1409 
  1410 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1411 
  1412 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1413 
  1414 * The function "cprod_map" has been renamed to "prod_map".
  1415 INCOMPATIBILITY.
  1416 
  1417 * The monadic bind operator on each powerdomain has new binder syntax
  1418 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1419 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1420 
  1421 * The infix syntax for binary union on each powerdomain has changed
  1422 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1423 syntax.  INCOMPATIBILITY.
  1424 
  1425 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1426 still supported as an input translation.
  1427 
  1428 * Renamed some theorems (the original names are also still available).
  1429 
  1430   expand_fun_below   ~> fun_below_iff
  1431   below_fun_ext      ~> fun_belowI
  1432   expand_cfun_eq     ~> cfun_eq_iff
  1433   ext_cfun           ~> cfun_eqI
  1434   expand_cfun_below  ~> cfun_below_iff
  1435   below_cfun_ext     ~> cfun_belowI
  1436   cont2cont_Rep_CFun ~> cont2cont_APP
  1437 
  1438 * The Abs and Rep functions for various types have changed names.
  1439 Related theorem names have also changed to match. INCOMPATIBILITY.
  1440 
  1441   Rep_CFun  ~> Rep_cfun
  1442   Abs_CFun  ~> Abs_cfun
  1443   Rep_Sprod ~> Rep_sprod
  1444   Abs_Sprod ~> Abs_sprod
  1445   Rep_Ssum  ~> Rep_ssum
  1446   Abs_Ssum  ~> Abs_ssum
  1447 
  1448 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1449 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1450 
  1451 * Various changes to bisimulation/coinduction with domain package:
  1452 
  1453   - Definitions of "bisim" constants no longer mention definedness.
  1454   - With mutual recursion, "bisim" predicate is now curried.
  1455   - With mutual recursion, each type gets a separate coind theorem.
  1456   - Variable names in bisim_def and coinduct rules have changed.
  1457 
  1458 INCOMPATIBILITY.
  1459 
  1460 * Case combinators generated by the domain package for type "foo" are
  1461 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1462 
  1463 * Several theorems have been renamed to more accurately reflect the
  1464 names of constants and types involved.  INCOMPATIBILITY.
  1465 
  1466   thelub_const    ~> lub_const
  1467   lub_const       ~> is_lub_const
  1468   thelubI         ~> lub_eqI
  1469   is_lub_lub      ~> is_lubD2
  1470   lubI            ~> is_lub_lub
  1471   unique_lub      ~> is_lub_unique
  1472   is_ub_lub       ~> is_lub_rangeD1
  1473   lub_bin_chain   ~> is_lub_bin_chain
  1474   lub_fun         ~> is_lub_fun
  1475   thelub_fun      ~> lub_fun
  1476   thelub_cfun     ~> lub_cfun
  1477   thelub_Pair     ~> lub_Pair
  1478   lub_cprod       ~> is_lub_prod
  1479   thelub_cprod    ~> lub_prod
  1480   minimal_cprod   ~> minimal_prod
  1481   inst_cprod_pcpo ~> inst_prod_pcpo
  1482   UU_I            ~> bottomI
  1483   compact_UU      ~> compact_bottom
  1484   deflation_UU    ~> deflation_bottom
  1485   finite_deflation_UU ~> finite_deflation_bottom
  1486 
  1487 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1488 
  1489   sq_ord_less_eq_trans ~> below_eq_trans
  1490   sq_ord_eq_less_trans ~> eq_below_trans
  1491   refl_less            ~> below_refl
  1492   trans_less           ~> below_trans
  1493   antisym_less         ~> below_antisym
  1494   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1495   box_less             ~> box_below
  1496   rev_trans_less       ~> rev_below_trans
  1497   not_less2not_eq      ~> not_below2not_eq
  1498   less_UU_iff          ~> below_UU_iff
  1499   flat_less_iff        ~> flat_below_iff
  1500   adm_less             ~> adm_below
  1501   adm_not_less         ~> adm_not_below
  1502   adm_compact_not_less ~> adm_compact_not_below
  1503   less_fun_def         ~> below_fun_def
  1504   expand_fun_less      ~> fun_below_iff
  1505   less_fun_ext         ~> fun_belowI
  1506   less_discr_def       ~> below_discr_def
  1507   discr_less_eq        ~> discr_below_eq
  1508   less_unit_def        ~> below_unit_def
  1509   less_cprod_def       ~> below_prod_def
  1510   prod_lessI           ~> prod_belowI
  1511   Pair_less_iff        ~> Pair_below_iff
  1512   fst_less_iff         ~> fst_below_iff
  1513   snd_less_iff         ~> snd_below_iff
  1514   expand_cfun_less     ~> cfun_below_iff
  1515   less_cfun_ext        ~> cfun_belowI
  1516   injection_less       ~> injection_below
  1517   less_up_def          ~> below_up_def
  1518   not_Iup_less         ~> not_Iup_below
  1519   Iup_less             ~> Iup_below
  1520   up_less              ~> up_below
  1521   Def_inject_less_eq   ~> Def_below_Def
  1522   Def_less_is_eq       ~> Def_below_iff
  1523   spair_less_iff       ~> spair_below_iff
  1524   less_sprod           ~> below_sprod
  1525   spair_less           ~> spair_below
  1526   sfst_less_iff        ~> sfst_below_iff
  1527   ssnd_less_iff        ~> ssnd_below_iff
  1528   fix_least_less       ~> fix_least_below
  1529   dist_less_one        ~> dist_below_one
  1530   less_ONE             ~> below_ONE
  1531   ONE_less_iff         ~> ONE_below_iff
  1532   less_sinlD           ~> below_sinlD
  1533   less_sinrD           ~> below_sinrD
  1534 
  1535 
  1536 *** FOL and ZF ***
  1537 
  1538 * All constant names are now qualified internally and use proper
  1539 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1540 
  1541 
  1542 *** ML ***
  1543 
  1544 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1545 Fail if the argument is false.  Due to inlining the source position of
  1546 failed assertions is included in the error output.
  1547 
  1548 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1549 text is in practice always evaluated with a stable theory checkpoint.
  1550 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1551 
  1552 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1553 the current context, not any accidental theory loader state as before.
  1554 Potential INCOMPATIBILITY, subtle change in semantics.
  1555 
  1556 * Syntax.pretty_priority (default 0) configures the required priority
  1557 of pretty-printed output and thus affects insertion of parentheses.
  1558 
  1559 * Syntax.default_root (default "any") configures the inner syntax
  1560 category (nonterminal symbol) for parsing of terms.
  1561 
  1562 * Former exception Library.UnequalLengths now coincides with
  1563 ListPair.UnequalLengths.
  1564 
  1565 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1566 main functionality is provided by structure Simplifier.
  1567 
  1568 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1569 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1570 almost all situations.
  1571 
  1572 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1573 See implementation manual for further details on exceptions in
  1574 Isabelle/ML.
  1575 
  1576 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1577 meaning.
  1578 
  1579 * Renamed structure PureThy to Pure_Thy and moved most of its
  1580 operations to structure Global_Theory, to emphasize that this is
  1581 rarely-used global-only stuff.
  1582 
  1583 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1584 instead (or tracing for high-volume output).
  1585 
  1586 * Configuration option show_question_marks only affects regular pretty
  1587 printing of types and terms, not raw Term.string_of_vname.
  1588 
  1589 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1590 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1591 @{thms} for most purposes.
  1592 
  1593 * ML structure Unsynchronized is never opened, not even in Isar
  1594 interaction mode as before.  Old Unsynchronized.set etc. have been
  1595 discontinued -- use plain := instead.  This should be *rare* anyway,
  1596 since modern tools always work via official context data, notably
  1597 configuration options.
  1598 
  1599 * Parallel and asynchronous execution requires special care concerning
  1600 interrupts.  Structure Exn provides some convenience functions that
  1601 avoid working directly with raw Interrupt.  User code must not absorb
  1602 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1603 followed by re-raising of the original exception.  Another common
  1604 source of mistakes are "handle _" patterns, which make the meaning of
  1605 the program subject to physical effects of the environment.
  1606 
  1607 
  1608 
  1609 New in Isabelle2009-2 (June 2010)
  1610 ---------------------------------
  1611 
  1612 *** General ***
  1613 
  1614 * Authentic syntax for *all* logical entities (type classes, type
  1615 constructors, term constants): provides simple and robust
  1616 correspondence between formal entities and concrete syntax.  Within
  1617 the parse tree / AST representations, "constants" are decorated by
  1618 their category (class, type, const) and spelled out explicitly with
  1619 their full internal name.
  1620 
  1621 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1622 and translations (translation rules and translation functions in ML).
  1623 Some hints on upgrading:
  1624 
  1625   - Many existing uses of 'syntax' and 'translations' can be replaced
  1626     by more modern 'type_notation', 'notation' and 'abbreviation',
  1627     which are independent of this issue.
  1628 
  1629   - 'translations' require markup within the AST; the term syntax
  1630     provides the following special forms:
  1631 
  1632       CONST c   -- produces syntax version of constant c from context
  1633       XCONST c  -- literally c, checked as constant from context
  1634       c         -- literally c, if declared by 'syntax'
  1635 
  1636     Plain identifiers are treated as AST variables -- occasionally the
  1637     system indicates accidental variables via the error "rhs contains
  1638     extra variables".
  1639 
  1640     Type classes and type constructors are marked according to their
  1641     concrete syntax.  Some old translations rules need to be written
  1642     for the "type" category, using type constructor application
  1643     instead of pseudo-term application of the default category
  1644     "logic".
  1645 
  1646   - 'parse_translation' etc. in ML may use the following
  1647     antiquotations:
  1648 
  1649       @{class_syntax c}   -- type class c within parse tree / AST
  1650       @{term_syntax c}    -- type constructor c within parse tree / AST
  1651       @{const_syntax c}   -- ML version of "CONST c" above
  1652       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1653 
  1654   - Literal types within 'typed_print_translations', i.e. those *not*
  1655     represented as pseudo-terms are represented verbatim.  Use @{class
  1656     c} or @{type_name c} here instead of the above syntax
  1657     antiquotations.
  1658 
  1659 Note that old non-authentic syntax was based on unqualified base
  1660 names, so all of the above "constant" names would coincide.  Recall
  1661 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1662 diagnose syntax problems.
  1663 
  1664 * Type constructors admit general mixfix syntax, not just infix.
  1665 
  1666 * Concrete syntax may be attached to local entities without a proof
  1667 body, too.  This works via regular mixfix annotations for 'fix',
  1668 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1669 similar to the 'notation' command in theory specifications.
  1670 
  1671 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1672 need to specify constant name and syntax separately.  Internal ML
  1673 datatype constructors have been renamed from InfixName to Infix etc.
  1674 Minor INCOMPATIBILITY.
  1675 
  1676 * Schematic theorem statements need to be explicitly markup as such,
  1677 via commands 'schematic_lemma', 'schematic_theorem',
  1678 'schematic_corollary'.  Thus the relevance of the proof is made
  1679 syntactically clear, which impacts performance in a parallel or
  1680 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1681 
  1682 * Use of cumulative prems via "!" in some proof methods has been
  1683 discontinued (old legacy feature).
  1684 
  1685 * References 'trace_simp' and 'debug_simp' have been replaced by
  1686 configuration options stored in the context. Enabling tracing (the
  1687 case of debugging is similar) in proofs works via
  1688 
  1689   using [[trace_simp = true]]
  1690 
  1691 Tracing is then active for all invocations of the simplifier in
  1692 subsequent goal refinement steps. Tracing may also still be enabled or
  1693 disabled via the ProofGeneral settings menu.
  1694 
  1695 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1696 'hide_fact' replace the former 'hide' KIND command.  Minor
  1697 INCOMPATIBILITY.
  1698 
  1699 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1700 more efficient than combinations with -q1 or -q2.
  1701 
  1702 
  1703 *** Pure ***
  1704 
  1705 * Proofterms record type-class reasoning explicitly, using the
  1706 "unconstrain" operation internally.  This eliminates all sort
  1707 constraints from a theorem and proof, introducing explicit
  1708 OFCLASS-premises.  On the proof term level, this operation is
  1709 automatically applied at theorem boundaries, such that closed proofs
  1710 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1711 inspect proof terms.
  1712 
  1713 * Local theory specifications may depend on extra type variables that
  1714 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1715 are added internally.  For example:
  1716 
  1717   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1718 
  1719 * Predicates of locales introduced by classes carry a mandatory
  1720 "class" prefix.  INCOMPATIBILITY.
  1721 
  1722 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1723 
  1724 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1725 'class' instead.
  1726 
  1727 * Command 'code_reflect' allows to incorporate generated ML code into
  1728 runtime environment; replaces immature code_datatype antiquotation.
  1729 INCOMPATIBILITY.
  1730 
  1731 * Code generator: simple concept for abstract datatypes obeying
  1732 invariants.
  1733 
  1734 * Code generator: details of internal data cache have no impact on the
  1735 user space functionality any longer.
  1736 
  1737 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1738 subgoals.  This is more appropriate for interpretations with 'where'.
  1739 INCOMPATIBILITY.
  1740 
  1741 * Command 'example_proof' opens an empty proof body.  This allows to
  1742 experiment with Isar, without producing any persistent result.
  1743 
  1744 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1745 within a local theory context, with explicit checking of the
  1746 constructors involved (in contrast to the raw 'syntax' versions).
  1747 
  1748 * Commands 'types' and 'typedecl' now work within a local theory
  1749 context -- without introducing dependencies on parameters or
  1750 assumptions, which is not possible in Isabelle/Pure.
  1751 
  1752 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1753 within a local theory context.  Minor INCOMPATIBILITY.
  1754 
  1755 
  1756 *** HOL ***
  1757 
  1758 * Command 'typedef' now works within a local theory context -- without
  1759 introducing dependencies on parameters or assumptions, which is not
  1760 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1761 contain multiple interpretations of local typedefs (with different
  1762 non-emptiness proofs), even in a global theory context.
  1763 
  1764 * New package for quotient types.  Commands 'quotient_type' and
  1765 'quotient_definition' may be used for defining types and constants by
  1766 quotient constructions.  An example is the type of integers created by
  1767 quotienting pairs of natural numbers:
  1768 
  1769   fun
  1770     intrel :: "(nat * nat) => (nat * nat) => bool"
  1771   where
  1772     "intrel (x, y) (u, v) = (x + v = u + y)"
  1773 
  1774   quotient_type int = "nat * nat" / intrel
  1775     by (auto simp add: equivp_def expand_fun_eq)
  1776 
  1777   quotient_definition
  1778     "0::int" is "(0::nat, 0::nat)"
  1779 
  1780 The method "lifting" can be used to lift of theorems from the
  1781 underlying "raw" type to the quotient type.  The example
  1782 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1783 construction and provides a reasoning infrastructure for finite sets.
  1784 
  1785 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1786 clash with new theory Quotient in Main HOL.
  1787 
  1788 * Moved the SMT binding into the main HOL session, eliminating
  1789 separate HOL-SMT session.
  1790 
  1791 * List membership infix mem operation is only an input abbreviation.
  1792 INCOMPATIBILITY.
  1793 
  1794 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1795 for future developements; former Library/Word.thy is still present in
  1796 the AFP entry RSAPPS.
  1797 
  1798 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1799 longer shadowed.  INCOMPATIBILITY.
  1800 
  1801 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1802 INCOMPATIBILITY.
  1803 
  1804 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1805 INCOMPATIBILITY.
  1806 
  1807 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1808 instead.  INCOMPATIBILITY.
  1809 
  1810 * Dropped several real-specific versions of lemmas about floor and
  1811 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1812 instead.  INCOMPATIBILITY.
  1813 
  1814   floor_number_of_eq         ~> floor_number_of
  1815   le_floor_eq_number_of      ~> number_of_le_floor
  1816   le_floor_eq_zero           ~> zero_le_floor
  1817   le_floor_eq_one            ~> one_le_floor
  1818   floor_less_eq_number_of    ~> floor_less_number_of
  1819   floor_less_eq_zero         ~> floor_less_zero
  1820   floor_less_eq_one          ~> floor_less_one
  1821   less_floor_eq_number_of    ~> number_of_less_floor
  1822   less_floor_eq_zero         ~> zero_less_floor
  1823   less_floor_eq_one          ~> one_less_floor
  1824   floor_le_eq_number_of      ~> floor_le_number_of
  1825   floor_le_eq_zero           ~> floor_le_zero
  1826   floor_le_eq_one            ~> floor_le_one
  1827   floor_subtract_number_of   ~> floor_diff_number_of
  1828   floor_subtract_one         ~> floor_diff_one
  1829   ceiling_number_of_eq       ~> ceiling_number_of
  1830   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1831   ceiling_le_zero_eq         ~> ceiling_le_zero
  1832   ceiling_le_eq_one          ~> ceiling_le_one
  1833   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1834   less_ceiling_eq_zero       ~> zero_less_ceiling
  1835   less_ceiling_eq_one        ~> one_less_ceiling
  1836   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1837   ceiling_less_eq_zero       ~> ceiling_less_zero
  1838   ceiling_less_eq_one        ~> ceiling_less_one
  1839   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1840   le_ceiling_eq_zero         ~> zero_le_ceiling
  1841   le_ceiling_eq_one          ~> one_le_ceiling
  1842   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1843   ceiling_subtract_one       ~> ceiling_diff_one
  1844 
  1845 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1846 application of the various fold combinators on finite sets.
  1847 
  1848 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1849 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1850 implementation.  INCOMPATIBILTY.
  1851 
  1852 * Theory Library/Coinductive_List has been removed -- superseded by
  1853 AFP/thys/Coinductive.
  1854 
  1855 * Theory PReal, including the type "preal" and related operations, has
  1856 been removed.  INCOMPATIBILITY.
  1857 
  1858 * Real: new development using Cauchy Sequences.
  1859 
  1860 * Split off theory "Big_Operators" containing setsum, setprod,
  1861 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1862 
  1863 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1864 "Int" etc.  INCOMPATIBILITY.
  1865 
  1866 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1867 
  1868 * New set of rules "ac_simps" provides combined assoc / commute
  1869 rewrites for all interpretations of the appropriate generic locales.
  1870 
  1871 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1872 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1873 appropriate and more consistent names suitable for name prefixes
  1874 within the HOL theories.  INCOMPATIBILITY.
  1875 
  1876 * Some generic constants have been put to appropriate theories:
  1877   - less_eq, less: Orderings
  1878   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1879   - inverse, divide: Rings
  1880 INCOMPATIBILITY.
  1881 
  1882 * More consistent naming of type classes involving orderings (and
  1883 lattices):
  1884 
  1885     lower_semilattice                   ~> semilattice_inf
  1886     upper_semilattice                   ~> semilattice_sup
  1887 
  1888     dense_linear_order                  ~> dense_linorder
  1889 
  1890     pordered_ab_group_add               ~> ordered_ab_group_add
  1891     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1892     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1893     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1894     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1895     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1896     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1897     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1898     pordered_comm_ring                  ~> ordered_comm_ring
  1899     pordered_comm_semiring              ~> ordered_comm_semiring
  1900     pordered_ring                       ~> ordered_ring
  1901     pordered_ring_abs                   ~> ordered_ring_abs
  1902     pordered_semiring                   ~> ordered_semiring
  1903 
  1904     ordered_ab_group_add                ~> linordered_ab_group_add
  1905     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1906     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1907     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1908     ordered_field                       ~> linordered_field
  1909     ordered_field_no_lb                 ~> linordered_field_no_lb
  1910     ordered_field_no_ub                 ~> linordered_field_no_ub
  1911     ordered_field_dense_linear_order    ~> dense_linordered_field
  1912     ordered_idom                        ~> linordered_idom
  1913     ordered_ring                        ~> linordered_ring
  1914     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1915     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1916     ordered_ring_strict                 ~> linordered_ring_strict
  1917     ordered_semidom                     ~> linordered_semidom
  1918     ordered_semiring                    ~> linordered_semiring
  1919     ordered_semiring_1                  ~> linordered_semiring_1
  1920     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1921     ordered_semiring_strict             ~> linordered_semiring_strict
  1922 
  1923   The following slightly odd type classes have been moved to a
  1924   separate theory Library/Lattice_Algebras:
  1925 
  1926     lordered_ab_group_add               ~> lattice_ab_group_add
  1927     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1928     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1929     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1930     lordered_ring                       ~> lattice_ring
  1931 
  1932 INCOMPATIBILITY.
  1933 
  1934 * Refined field classes:
  1935   - classes division_ring_inverse_zero, field_inverse_zero,
  1936     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1937     subsumes former division_by_zero class;
  1938   - numerous lemmas have been ported from field to division_ring.
  1939 INCOMPATIBILITY.
  1940 
  1941 * Refined algebra theorem collections:
  1942   - dropped theorem group group_simps, use algebra_simps instead;
  1943   - dropped theorem group ring_simps, use field_simps instead;
  1944   - proper theorem collection field_simps subsumes former theorem
  1945     groups field_eq_simps and field_simps;
  1946   - dropped lemma eq_minus_self_iff which is a duplicate for
  1947     equal_neg_zero.
  1948 INCOMPATIBILITY.
  1949 
  1950 * Theory Finite_Set and List: some lemmas have been generalized from
  1951 sets to lattices:
  1952 
  1953   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1954   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1955   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1956   union_Union_fold_union        ~> sup_Sup_fold_sup
  1957   Inter_fold_inter              ~> Inf_fold_inf
  1958   Union_fold_union              ~> Sup_fold_sup
  1959   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1960   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1961   INTER_fold_inter              ~> INFI_fold_inf
  1962   UNION_fold_union              ~> SUPR_fold_sup
  1963 
  1964 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1965 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1966 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1967 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1968 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1969 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1970 
  1971 * Reorganized theory Multiset: swapped notation of pointwise and
  1972 multiset order:
  1973 
  1974   - pointwise ordering is instance of class order with standard syntax
  1975     <= and <;
  1976   - multiset ordering has syntax <=# and <#; partial order properties
  1977     are provided by means of interpretation with prefix
  1978     multiset_order;
  1979   - less duplication, less historical organization of sections,
  1980     conversion from associations lists to multisets, rudimentary code
  1981     generation;
  1982   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1983     if needed.
  1984 
  1985 Renamed:
  1986 
  1987   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1988   multi_count_ext  ~>  multiset_ext
  1989   diff_union_inverse2  ~>  diff_union_cancelR
  1990 
  1991 INCOMPATIBILITY.
  1992 
  1993 * Theory Permutation: replaced local "remove" by List.remove1.
  1994 
  1995 * Code generation: ML and OCaml code is decorated with signatures.
  1996 
  1997 * Theory List: added transpose.
  1998 
  1999 * Library/Nat_Bijection.thy is a collection of bijective functions
  2000 between nat and other types, which supersedes the older libraries
  2001 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  2002 
  2003   Constants:
  2004   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  2005   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  2006   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  2007   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  2008   Countable.pair_encode           ~> prod_encode
  2009   NatIso.prod2nat                 ~> prod_encode
  2010   NatIso.nat2prod                 ~> prod_decode
  2011   NatIso.sum2nat                  ~> sum_encode
  2012   NatIso.nat2sum                  ~> sum_decode
  2013   NatIso.list2nat                 ~> list_encode
  2014   NatIso.nat2list                 ~> list_decode
  2015   NatIso.set2nat                  ~> set_encode
  2016   NatIso.nat2set                  ~> set_decode
  2017 
  2018   Lemmas:
  2019   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2020   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2021   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2022   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2023   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2024   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2025   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2026   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2027   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2028   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2029   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2030   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2031   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2032 
  2033 * Sledgehammer:
  2034   - Renamed ATP commands:
  2035     atp_info     ~> sledgehammer running_atps
  2036     atp_kill     ~> sledgehammer kill_atps
  2037     atp_messages ~> sledgehammer messages
  2038     atp_minimize ~> sledgehammer minimize
  2039     print_atps   ~> sledgehammer available_atps
  2040     INCOMPATIBILITY.
  2041   - Added user's manual ("isabelle doc sledgehammer").
  2042   - Added option syntax and "sledgehammer_params" to customize
  2043     Sledgehammer's behavior.  See the manual for details.
  2044   - Modified the Isar proof reconstruction code so that it produces
  2045     direct proofs rather than proofs by contradiction.  (This feature
  2046     is still experimental.)
  2047   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2048     full-typed mode.
  2049   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2050 
  2051 * Nitpick:
  2052   - Added and implemented "binary_ints" and "bits" options.
  2053   - Added "std" option and implemented support for nonstandard models.
  2054   - Added and implemented "finitize" option to improve the precision
  2055     of infinite datatypes based on a monotonicity analysis.
  2056   - Added support for quotient types.
  2057   - Added support for "specification" and "ax_specification"
  2058     constructs.
  2059   - Added support for local definitions (for "function" and
  2060     "termination" proofs).
  2061   - Added support for term postprocessors.
  2062   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2063   - Improved efficiency of "destroy_constrs" optimization.
  2064   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2065     record getters.
  2066   - Fixed soundness bug related to higher-order constructors.
  2067   - Fixed soundness bug when "full_descrs" is enabled.
  2068   - Improved precision of set constructs.
  2069   - Added "atoms" option.
  2070   - Added cache to speed up repeated Kodkod invocations on the same
  2071     problems.
  2072   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2073     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2074     "SAT4J_Light".  INCOMPATIBILITY.
  2075   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2076     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2077   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2078 
  2079 * Method "induct" now takes instantiations of the form t, where t is not
  2080   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2081   If this is not intended, t has to be enclosed in parentheses.
  2082   By default, the equalities generated by definitional instantiations
  2083   are pre-simplified, which may cause parameters of inductive cases
  2084   to disappear, or may even delete some of the inductive cases.
  2085   Use "induct (no_simp)" instead of "induct" to restore the old
  2086   behaviour. The (no_simp) option is also understood by the "cases"
  2087   and "nominal_induct" methods, which now perform pre-simplification, too.
  2088   INCOMPATIBILITY.
  2089 
  2090 
  2091 *** HOLCF ***
  2092 
  2093 * Variable names in lemmas generated by the domain package have
  2094 changed; the naming scheme is now consistent with the HOL datatype
  2095 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2096 
  2097 * The domain package no longer defines the function "foo_copy" for
  2098 recursive domain "foo".  The reach lemma is now stated directly in
  2099 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2100 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2101 
  2102 * Most definedness lemmas generated by the domain package (previously
  2103 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2104 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2105 Proofs that used definedness lemmas as intro rules may break,
  2106 potential INCOMPATIBILITY.
  2107 
  2108 * Induction and casedist rules generated by the domain package now
  2109 declare proper case_names (one called "bottom", and one named for each
  2110 constructor).  INCOMPATIBILITY.
  2111 
  2112 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2113 rules are generated for each domain, INCOMPATIBILITY.
  2114 
  2115   foo_bar.reach       ~> foo.reach  bar.reach
  2116   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2117 
  2118 * Some lemmas generated by the domain package have been renamed for
  2119 consistency with the datatype package, INCOMPATIBILITY.
  2120 
  2121   foo.ind        ~> foo.induct
  2122   foo.finite_ind ~> foo.finite_induct
  2123   foo.coind      ~> foo.coinduct
  2124   foo.casedist   ~> foo.exhaust
  2125   foo.exhaust    ~> foo.nchotomy
  2126 
  2127 * For consistency with other definition packages, the fixrec package
  2128 now generates qualified theorem names, INCOMPATIBILITY.
  2129 
  2130   foo_simps  ~> foo.simps
  2131   foo_unfold ~> foo.unfold
  2132   foo_induct ~> foo.induct
  2133 
  2134 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2135 method and internal fixrec proofs now use the default simpset instead.
  2136 INCOMPATIBILITY.
  2137 
  2138 * The "contlub" predicate has been removed.  Proof scripts should use
  2139 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2140 
  2141 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2142 
  2143 * The constants cpair, cfst, and csnd have been removed in favor of
  2144 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2145 
  2146 
  2147 *** ML ***
  2148 
  2149 * Antiquotations for basic formal entities:
  2150 
  2151     @{class NAME}         -- type class
  2152     @{class_syntax NAME}  -- syntax representation of the above
  2153 
  2154     @{type_name NAME}     -- logical type
  2155     @{type_abbrev NAME}   -- type abbreviation
  2156     @{nonterminal NAME}   -- type of concrete syntactic category
  2157     @{type_syntax NAME}   -- syntax representation of any of the above
  2158 
  2159     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2160     @{const_abbrev NAME}  -- abbreviated constant
  2161     @{const_syntax NAME}  -- syntax representation of any of the above
  2162 
  2163 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2164 syntax constant (cf. 'syntax' command).
  2165 
  2166 * Antiquotation @{make_string} inlines a function to print arbitrary
  2167 values similar to the ML toplevel.  The result is compiler dependent
  2168 and may fall back on "?" in certain situations.
  2169 
  2170 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2171 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2172 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2173 not work with the asynchronous Isar document model.
  2174 
  2175 * Configuration options now admit dynamic default values, depending on
  2176 the context or even global references.
  2177 
  2178 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2179 uses an efficient external library if available (for Poly/ML).
  2180 
  2181 * Renamed some important ML structures, while keeping the old names
  2182 for some time as aliases within the structure Legacy:
  2183 
  2184   OuterKeyword  ~>  Keyword
  2185   OuterLex      ~>  Token
  2186   OuterParse    ~>  Parse
  2187   OuterSyntax   ~>  Outer_Syntax
  2188   PrintMode     ~>  Print_Mode
  2189   SpecParse     ~>  Parse_Spec
  2190   ThyInfo       ~>  Thy_Info
  2191   ThyLoad       ~>  Thy_Load
  2192   ThyOutput     ~>  Thy_Output
  2193   TypeInfer     ~>  Type_Infer
  2194 
  2195 Note that "open Legacy" simplifies porting of sources, but forgetting
  2196 to remove it again will complicate porting again in the future.
  2197 
  2198 * Most operations that refer to a global context are named
  2199 accordingly, e.g. Simplifier.global_context or
  2200 ProofContext.init_global.  There are some situations where a global
  2201 context actually works, but under normal circumstances one needs to
  2202 pass the proper local context through the code!
  2203 
  2204 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2205 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2206 Pretty.pp argument to merge, which is absent in the standard
  2207 Theory_Data version.
  2208 
  2209 * Sorts.certify_sort and derived "cert" operations for types and terms
  2210 no longer minimize sorts.  Thus certification at the boundary of the
  2211 inference kernel becomes invariant under addition of class relations,
  2212 which is an important monotonicity principle.  Sorts are now minimized
  2213 in the syntax layer only, at the boundary between the end-user and the
  2214 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2215 explicitly in rare situations.
  2216 
  2217 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2218 emphasize that this is in no way a standard operation.
  2219 INCOMPATIBILITY.
  2220 
  2221 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2222 usual for resolution.  Rare INCOMPATIBILITY.
  2223 
  2224 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2225 to emphasize that these only work in a global situation (which is
  2226 quite rare).
  2227 
  2228 * Curried take and drop in library.ML; negative length is interpreted
  2229 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2230 
  2231 * Proof terms: type substitutions on proof constants now use canonical
  2232 order of type variables.  INCOMPATIBILITY for tools working with proof
  2233 terms.
  2234 
  2235 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2236 may no longer carry premises.  User-level specifications are
  2237 transformed accordingly by Thm.add_axiom/add_def.
  2238 
  2239 
  2240 *** System ***
  2241 
  2242 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2243 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2244 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2245 
  2246 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2247 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2248 respectively.
  2249 
  2250 * Old lib/scripts/polyml-platform is superseded by the
  2251 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2252 variant, even on a 64 bit machine.  The following example setting
  2253 prefers 64 bit if available:
  2254 
  2255   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2256 
  2257 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2258 Isabelle/Scala layer for advanced prover interaction and integration.
  2259 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2260 component.
  2261 
  2262 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2263 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2264 similar to the default assignment of the document preparation system
  2265 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2266 provides some operations for direct access to the font without asking
  2267 the user for manual installation.
  2268 
  2269 
  2270 
  2271 New in Isabelle2009-1 (December 2009)
  2272 -------------------------------------
  2273 
  2274 *** General ***
  2275 
  2276 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2277 one backslash should be used, even in ML sources.
  2278 
  2279 
  2280 *** Pure ***
  2281 
  2282 * Locale interpretation propagates mixins along the locale hierarchy.
  2283 The currently only available mixins are the equations used to map
  2284 local definitions to terms of the target domain of an interpretation.
  2285 
  2286 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2287 loc" to print all interpretations of locale "loc" in the theory.
  2288 Interpretations in proofs are not shown.
  2289 
  2290 * Thoroughly revised locales tutorial.  New section on conditional
  2291 interpretation.
  2292 
  2293 * On instantiation of classes, remaining undefined class parameters
  2294 are formally declared.  INCOMPATIBILITY.
  2295 
  2296 
  2297 *** Document preparation ***
  2298 
  2299 * New generalized style concept for printing terms: @{foo (style) ...}
  2300 instead of @{foo_style style ...}  (old form is still retained for
  2301 backward compatibility).  Styles can be also applied for
  2302 antiquotations prop, term_type and typeof.
  2303 
  2304 
  2305 *** HOL ***
  2306 
  2307 * New proof method "smt" for a combination of first-order logic with
  2308 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2309 fixed-size bitvectors; there is also basic support for higher-order
  2310 features (esp. lambda abstractions).  It is an incomplete decision
  2311 procedure based on external SMT solvers using the oracle mechanism;
  2312 for the SMT solver Z3, this method is proof-producing.  Certificates
  2313 are provided to avoid calling the external solvers solely for
  2314 re-checking proofs.  Due to a remote SMT service there is no need for
  2315 installing SMT solvers locally.  See src/HOL/SMT.
  2316 
  2317 * New commands to load and prove verification conditions generated by
  2318 the Boogie program verifier or derived systems (e.g. the Verifying C
  2319 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2320 
  2321 * New counterexample generator tool 'nitpick' based on the Kodkod
  2322 relational model finder.  See src/HOL/Tools/Nitpick and
  2323 src/HOL/Nitpick_Examples.
  2324 
  2325 * New commands 'code_pred' and 'values' to invoke the predicate
  2326 compiler and to enumerate values of inductive predicates.
  2327 
  2328 * A tabled implementation of the reflexive transitive closure.
  2329 
  2330 * New implementation of quickcheck uses generic code generator;
  2331 default generators are provided for all suitable HOL types, records
  2332 and datatypes.  Old quickcheck can be re-activated importing theory
  2333 Library/SML_Quickcheck.
  2334 
  2335 * New testing tool Mirabelle for automated proof tools.  Applies
  2336 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2337 every proof step in a theory.  To be used in batch mode via the
  2338 "mirabelle" utility.
  2339 
  2340 * New proof method "sos" (sum of squares) for nonlinear real
  2341 arithmetic (originally due to John Harison). It requires theory
  2342 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2343 works well in practice on quantifier-free real arithmetic with +, -,
  2344 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2345 inequalities between polynomials.  It makes use of external
  2346 semidefinite programming solvers.  Method "sos" generates a
  2347 certificate that can be pasted into the proof thus avoiding the need
  2348 to call an external tool every time the proof is checked.  See
  2349 src/HOL/Library/Sum_Of_Squares.
  2350 
  2351 * New method "linarith" invokes existing linear arithmetic decision
  2352 procedure only.
  2353 
  2354 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2355 
  2356 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2357 Causes full type information to be output to the ATPs.  This slows
  2358 ATPs down considerably but eliminates a source of unsound "proofs"
  2359 that fail later.
  2360 
  2361 * New method "metisFT": A version of metis that uses full type
  2362 information in order to avoid failures of proof reconstruction.
  2363 
  2364 * New evaluator "approximate" approximates an real valued term using
  2365 the same method as the approximation method.
  2366 
  2367 * Method "approximate" now supports arithmetic expressions as
  2368 boundaries of intervals and implements interval splitting and Taylor
  2369 series expansion.
  2370 
  2371 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2372 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2373 
  2374 * New theory SupInf of the supremum and infimum operators for sets of
  2375 reals.
  2376 
  2377 * New theory Probability, which contains a development of measure
  2378 theory, eventually leading to Lebesgue integration and probability.
  2379 
  2380 * Extended Multivariate Analysis to include derivation and Brouwer's
  2381 fixpoint theorem.
  2382 
  2383 * Reorganization of number theory, INCOMPATIBILITY:
  2384   - new number theory development for nat and int, in theories Divides
  2385     and GCD as well as in new session Number_Theory
  2386   - some constants and facts now suffixed with _nat and _int
  2387     accordingly
  2388   - former session NumberTheory now named Old_Number_Theory, including
  2389     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2390   - moved theory Pocklington from src/HOL/Library to
  2391     src/HOL/Old_Number_Theory
  2392 
  2393 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2394 lcm of finite and infinite sets. It is shown that they form a complete
  2395 lattice.
  2396 
  2397 * Class semiring_div requires superclass no_zero_divisors and proof of
  2398 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2399 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2400 generalized to class semiring_div, subsuming former theorems
  2401 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2402 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2403 INCOMPATIBILITY.
  2404 
  2405 * Refinements to lattice classes and sets:
  2406   - less default intro/elim rules in locale variant, more default
  2407     intro/elim rules in class variant: more uniformity
  2408   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2409     le_inf_iff
  2410   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2411     sup_aci)
  2412   - renamed ACI to inf_sup_aci
  2413   - new class "boolean_algebra"
  2414   - class "complete_lattice" moved to separate theory
  2415     "Complete_Lattice"; corresponding constants (and abbreviations)
  2416     renamed and with authentic syntax:
  2417     Set.Inf ~>    Complete_Lattice.Inf
  2418     Set.Sup ~>    Complete_Lattice.Sup
  2419     Set.INFI ~>   Complete_Lattice.INFI
  2420     Set.SUPR ~>   Complete_Lattice.SUPR
  2421     Set.Inter ~>  Complete_Lattice.Inter
  2422     Set.Union ~>  Complete_Lattice.Union
  2423     Set.INTER ~>  Complete_Lattice.INTER
  2424     Set.UNION ~>  Complete_Lattice.UNION
  2425   - authentic syntax for
  2426     Set.Pow
  2427     Set.image
  2428   - mere abbreviations:
  2429     Set.empty               (for bot)
  2430     Set.UNIV                (for top)
  2431     Set.inter               (for inf, formerly Set.Int)
  2432     Set.union               (for sup, formerly Set.Un)
  2433     Complete_Lattice.Inter  (for Inf)
  2434     Complete_Lattice.Union  (for Sup)
  2435     Complete_Lattice.INTER  (for INFI)
  2436     Complete_Lattice.UNION  (for SUPR)
  2437   - object-logic definitions as far as appropriate
  2438 
  2439 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2440 Un_subset_iff are explicitly deleted as default simp rules; then also
  2441 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2442 deleted to achieve the desired effect.
  2443 
  2444 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2445 rules by default any longer; the same applies to min_max.inf_absorb1
  2446 etc.  INCOMPATIBILITY.
  2447 
  2448 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2449 pred_set_conv by default.  INCOMPATIBILITY.
  2450 
  2451 * Power operations on relations and functions are now one dedicated
  2452 constant "compow" with infix syntax "^^".  Power operation on
  2453 multiplicative monoids retains syntax "^" and is now defined generic
  2454 in class power.  INCOMPATIBILITY.
  2455 
  2456 * Relation composition "R O S" now has a more standard argument order:
  2457 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2458 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2459 break, since the O_assoc rule was not rewritten like this.  Fix using
  2460 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2461 
  2462 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2463 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2464 INCOMPATIBILITY.
  2465 
  2466 * Most rules produced by inductive and datatype package have mandatory
  2467 prefixes.  INCOMPATIBILITY.
  2468 
  2469 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2470 the attribute of the same name.  Each of the theorems in the list
  2471 DERIV_intros assumes composition with an additional function and
  2472 matches a variable to the derivative, which has to be solved by the
  2473 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2474 of most elementary terms.  Former Maclauren.DERIV_tac and
  2475 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2476 INCOMPATIBILITY.
  2477 
  2478 * Code generator attributes follow the usual underscore convention:
  2479     code_unfold     replaces    code unfold
  2480     code_post       replaces    code post
  2481     etc.
  2482   INCOMPATIBILITY.
  2483 
  2484 * Renamed methods:
  2485     sizechange -> size_change
  2486     induct_scheme -> induction_schema
  2487   INCOMPATIBILITY.
  2488 
  2489 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2490 INCOMPATIBILITY, use "undefined" directly.
  2491 
  2492 * Renamed theorems:
  2493     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2494     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2495     Suc_plus1 -> Suc_eq_plus1
  2496     *anti_sym -> *antisym*
  2497     vector_less_eq_def -> vector_le_def
  2498   INCOMPATIBILITY.
  2499 
  2500 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2501 INCOMPATIBILITY.
  2502 
  2503 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2504 INCOMPATIBILITY.
  2505 
  2506 
  2507 *** HOLCF ***
  2508 
  2509 * Theory Representable defines a class "rep" of domains that are
  2510 representable (via an ep-pair) in the universal domain type "udom".
  2511 Instances are provided for all type constructors defined in HOLCF.
  2512 
  2513 * The 'new_domain' command is a purely definitional version of the
  2514 domain package, for representable domains.  Syntax is identical to the
  2515 old domain package.  The 'new_domain' package also supports indirect
  2516 recursion using previously-defined type constructors.  See
  2517 src/HOLCF/ex/New_Domain.thy for examples.
  2518 
  2519 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2520 on the left-hand side of an equation, and then performs
  2521 simplification.  Rewriting is done using rules declared with the
  2522 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2523 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2524 
  2525 * The pattern-match compiler in 'fixrec' can now handle constructors
  2526 with HOL function types.  Pattern-match combinators for the Pair
  2527 constructor are pre-configured.
  2528 
  2529 * The 'fixrec' package now produces better fixed-point induction rules
  2530 for mutually-recursive definitions:  Induction rules have conclusions
  2531 of the form "P foo bar" instead of "P <foo, bar>".
  2532 
  2533 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2534 been renamed to "below".  The name "below" now replaces "less" in many
  2535 theorem names.  (Legacy theorem names using "less" are still supported
  2536 as well.)
  2537 
  2538 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2539 patterns can be used to generate strictness rules, or to make
  2540 functions more strict (much like the bang-patterns supported by the
  2541 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2542 examples.
  2543 
  2544 
  2545 *** ML ***
  2546 
  2547 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2548 errors and run-time exceptions, including detailed source positions.
  2549 
  2550 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2551 identified entries, with some additional information such as source
  2552 position, logical grouping etc.
  2553 
  2554 * Theory and context data is now introduced by the simplified and
  2555 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2556 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2557 copy operation) is still available for some time.
  2558 
  2559 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2560 provides a high-level programming interface to synchronized state
  2561 variables with atomic update.  This works via pure function
  2562 application within a critical section -- its runtime should be as
  2563 short as possible; beware of deadlocks if critical code is nested,
  2564 either directly or indirectly via other synchronized variables!
  2565 
  2566 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2567 wraps raw ML references, explicitly indicating their non-thread-safe
  2568 behaviour.  The Isar toplevel keeps this structure open, to
  2569 accommodate Proof General as well as quick and dirty interactive
  2570 experiments with references.
  2571 
  2572 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2573 parallel tactical reasoning.
  2574 
  2575 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2576 are similar to SUBPROOF, but are slightly more flexible: only the
  2577 specified parts of the subgoal are imported into the context, and the
  2578 body tactic may introduce new subgoals and schematic variables.
  2579 
  2580 * Old tactical METAHYPS, which does not observe the proof context, has
  2581 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2582 or Subgoal.FOCUS etc.
  2583 
  2584 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2585 functors have their own ML name space there is no point to mark them
  2586 separately.)  Minor INCOMPATIBILITY.
  2587 
  2588 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2589 
  2590 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2591 INCOMPATIBILITY.
  2592 
  2593 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2594 mode, which avoids critical setmp.
  2595 
  2596 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2597 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2598 Attrib/Method.setup introduced in Isabelle2009.
  2599 
  2600 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2601 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2602 last resort.  INCOMPATIBILITY.
  2603 
  2604 * Display.pretty_thm now requires a proper context (cf. former
  2605 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2606 or even Display.pretty_thm_without_context as last resort.
  2607 INCOMPATIBILITY.
  2608 
  2609 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2610 Syntax.pretty_typ/term directly, preferably with proper context
  2611 instead of global theory.
  2612 
  2613 
  2614 *** System ***
  2615 
  2616 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2617 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2618 usedir option -q.
  2619 
  2620 * Support for additional "Isabelle components" via etc/components, see
  2621 also the system manual.
  2622 
  2623 * The isabelle makeall tool now operates on all components with
  2624 IsaMakefile, not just hardwired "logics".
  2625 
  2626 * Removed "compress" option from isabelle-process and isabelle usedir;
  2627 this is always enabled.
  2628 
  2629 * Discontinued support for Poly/ML 4.x versions.
  2630 
  2631 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2632 on a given logic image.  This requires the lighttpd webserver and is
  2633 currently supported on Linux only.
  2634 
  2635 
  2636 
  2637 New in Isabelle2009 (April 2009)
  2638 --------------------------------
  2639 
  2640 *** General ***
  2641 
  2642 * Simplified main Isabelle executables, with less surprises on
  2643 case-insensitive file-systems (such as Mac OS).
  2644 
  2645   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2646     "isatool."
  2647 
  2648   - The former "isabelle" alias for "isabelle-process" has been
  2649     removed (should rarely occur to regular users).
  2650 
  2651   - The former "isabelle-interface" and its alias "Isabelle" have been
  2652     removed (interfaces are now regular Isabelle tools).
  2653 
  2654 Within scripts and make files, the Isabelle environment variables
  2655 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2656 respectively.  (The latter are still available as legacy feature.)
  2657 
  2658 The old isabelle-interface wrapper could react in confusing ways if
  2659 the interface was uninstalled or changed otherwise.  Individual
  2660 interface tool configuration is now more explicit, see also the
  2661 Isabelle system manual.  In particular, Proof General is now available
  2662 via "isabelle emacs".
  2663 
  2664 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2665 purge installed copies of Isabelle executables and re-run "isabelle
  2666 install -p ...", or use symlinks.
  2667 
  2668 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2669 old ~/isabelle, which was slightly non-standard and apt to cause
  2670 surprises on case-insensitive file-systems (such as Mac OS).
  2671 
  2672 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2673 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2674 care is required when using older releases of Isabelle.  Note that
  2675 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2676 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2677 
  2678 * Proofs of fully specified statements are run in parallel on
  2679 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2680 a regular 4-core machine, if the initial heap space is made reasonably
  2681 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2682 
  2683 * The main reference manuals ("isar-ref", "implementation", and
  2684 "system") have been updated and extended.  Formally checked references
  2685 as hyperlinks are now available uniformly.
  2686 
  2687 
  2688 *** Pure ***
  2689 
  2690 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2691 respects.  The most important changes are listed below.  See the
  2692 Tutorial on Locales ("locales" manual) for details.
  2693 
  2694 - In locale expressions, instantiation replaces renaming.  Parameters
  2695 must be declared in a for clause.  To aid compatibility with previous
  2696 parameter inheritance, in locale declarations, parameters that are not
  2697 'touched' (instantiation position "_" or omitted) are implicitly added
  2698 with their syntax at the beginning of the for clause.
  2699 
  2700 - Syntax from abbreviations and definitions in locales is available in
  2701 locale expressions and context elements.  The latter is particularly
  2702 useful in locale declarations.
  2703 
  2704 - More flexible mechanisms to qualify names generated by locale
  2705 expressions.  Qualifiers (prefixes) may be specified in locale
  2706 expressions, and can be marked as mandatory (syntax: "name!:") or
  2707 optional (syntax "name?:").  The default depends for plain "name:"
  2708 depends on the situation where a locale expression is used: in
  2709 commands 'locale' and 'sublocale' prefixes are optional, in
  2710 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2711 implicit qualifiers derived from the parameter names of a locale are
  2712 no longer generated.
  2713 
  2714 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2715 instantiation clause in "interpretation" and "interpret" (square
  2716 brackets) is no longer available.  Use locale expressions.
  2717 
  2718 - When converting proof scripts, mandatory qualifiers in
  2719 'interpretation' and 'interpret' should be retained by default, even
  2720 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2721 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2722 in locale expressions range over a single locale instance only.
  2723 
  2724 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2725 In existing theorem specifications replace the includes element by the
  2726 respective context elements of the included locale, omitting those
  2727 that are already present in the theorem specification.  Multiple
  2728 assume elements of a locale should be replaced by a single one
  2729 involving the locale predicate.  In the proof body, declarations (most
  2730 notably theorems) may be regained by interpreting the respective
  2731 locales in the proof context as required (command "interpret").
  2732 
  2733 If using "includes" in replacement of a target solely because the
  2734 parameter types in the theorem are not as general as in the target,
  2735 consider declaring a new locale with additional type constraints on
  2736 the parameters (context element "constrains").
  2737 
  2738 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2739 
  2740 - Locale interpretation commands no longer attempt to simplify goal.
  2741 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2742 methods intro_locales and unfold_locales to clarify.
  2743 
  2744 - Locale interpretation commands no longer accept interpretation
  2745 attributes.  INCOMPATIBILITY.
  2746 
  2747 * Class declaration: so-called "base sort" must not be given in import
  2748 list any longer, but is inferred from the specification.  Particularly
  2749 in HOL, write
  2750 
  2751     class foo = ...
  2752 
  2753 instead of
  2754 
  2755     class foo = type + ...
  2756 
  2757 * Class target: global versions of theorems stemming do not carry a
  2758 parameter prefix any longer.  INCOMPATIBILITY.
  2759 
  2760 * Class 'instance' command no longer accepts attached definitions.
  2761 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2762 
  2763 * Recovered hiding of consts, which was accidentally broken in
  2764 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2765 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2766 
  2767 * Slightly more coherent Pure syntax, with updated documentation in
  2768 isar-ref manual.  Removed locales meta_term_syntax and
  2769 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2770 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2771 directly in regular applications.
  2772 
  2773 * There is a new syntactic category "float_const" for signed decimal
  2774 fractions (e.g. 123.45 or -123.45).
  2775 
  2776 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2777 interface with 'setup' command instead.
  2778 
  2779 * Command 'local_setup' is similar to 'setup', but operates on a local
  2780 theory context.
  2781 
  2782 * The 'axiomatization' command now only works within a global theory
  2783 context.  INCOMPATIBILITY.
  2784 
  2785 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2786 hypotheses.  Sorts required in the course of reasoning need to be
  2787 covered by the constraints in the initial statement, completed by the
  2788 type instance information of the background theory.  Non-trivial sort
  2789 hypotheses, which rarely occur in practice, may be specified via
  2790 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2791 
  2792   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2793 
  2794 The result contains an implicit sort hypotheses as before --
  2795 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2796 normalization.
  2797 
  2798 * Generalized Isar history, with support for linear undo, direct state
  2799 addressing etc.
  2800 
  2801 * Changed defaults for unify configuration options:
  2802 
  2803   unify_trace_bound = 50 (formerly 25)
  2804   unify_search_bound = 60 (formerly 30)
  2805 
  2806 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2807 
  2808   a) On theory merge, the last set of code equations for a particular
  2809      constant is taken (in accordance with the policy applied by other
  2810      parts of the code generator framework).
  2811 
  2812   b) Code equations stemming from explicit declarations (e.g. code
  2813      attribute) gain priority over default code equations stemming
  2814      from definition, primrec, fun etc.
  2815 
  2816 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2817 
  2818 * Unified theorem tables for both code generators.  Thus [code
  2819 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2820 
  2821 * Command 'find_consts' searches for constants based on type and name
  2822 patterns, e.g.
  2823 
  2824     find_consts "_ => bool"
  2825 
  2826 By default, matching is against subtypes, but it may be restricted to
  2827 the whole type.  Searching by name is possible.  Multiple queries are
  2828 conjunctive and queries may be negated by prefixing them with a
  2829 hyphen:
  2830 
  2831     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2832 
  2833 * New 'find_theorems' criterion "solves" matches theorems that
  2834 directly solve the current goal (modulo higher-order unification).
  2835 
  2836 * Auto solve feature for main theorem statements: whenever a new goal
  2837 is stated, "find_theorems solves" is called; any theorems that could
  2838 solve the lemma directly are listed as part of the goal state.
  2839 Cf. associated options in Proof General Isabelle settings menu,
  2840 enabled by default, with reasonable timeout for pathological cases of
  2841 higher-order unification.
  2842 
  2843 
  2844 *** Document preparation ***
  2845 
  2846 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2847 demanding keyword 'by' and supporting the full method expression
  2848 syntax just like the Isar command 'by'.
  2849 
  2850 
  2851 *** HOL ***
  2852 
  2853 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2854 points Main and Complex_Main remain as before.
  2855 
  2856 * Logic image HOL-Plain provides a minimal HOL with the most important
  2857 tools available (inductive, datatype, primrec, ...).  This facilitates
  2858 experimentation and tool development.  Note that user applications
  2859 (and library theories) should never refer to anything below theory
  2860 Main, as before.
  2861 
  2862 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2863 experimentation due to shorter build times.
  2864 
  2865 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2866 were previously part of former HOL-Complex.  Entry point Hyperreal
  2867 remains valid, but theories formerly using Complex_Main should now use
  2868 new entry point Hypercomplex.
  2869 
  2870 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2871 Posix processes.  Avoids potentially expensive forking of the ML
  2872 process.  New thread-based implementation also works on non-Unix
  2873 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2874 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2875 commands are covered in the isar-ref manual.
  2876 
  2877 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2878 sledgehammer without local ATP installation (Vampire etc.). Other
  2879 provers may be included via suitable ML wrappers, see also
  2880 src/HOL/ATP_Linkup.thy.
  2881 
  2882 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2883 menu.
  2884 
  2885 * The metis method no longer fails because the theorem is too trivial
  2886 (contains the empty clause).
  2887 
  2888 * The metis method now fails in the usual manner, rather than raising
  2889 an exception, if it determines that it cannot prove the theorem.
  2890 
  2891 * Method "coherent" implements a prover for coherent logic (see also
  2892 src/Tools/coherent.ML).
  2893 
  2894 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2895 "undefined" is the right choice to replace "arbitrary", though
  2896 logically there is no difference.  INCOMPATIBILITY.
  2897 
  2898 * Command "value" now integrates different evaluation mechanisms.  The
  2899 result of the first successful evaluation mechanism is printed.  In
  2900 square brackets a particular named evaluation mechanisms may be
  2901 specified (currently, [SML], [code] or [nbe]).  See further
  2902 src/HOL/ex/Eval_Examples.thy.
  2903 
  2904 * Normalization by evaluation now allows non-leftlinear equations.
  2905 Declare with attribute [code nbe].
  2906 
  2907 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2908 as the structured Isar versions "cases" and "induct", cf. the
  2909 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2910 are now presented as a list of individual projections
  2911 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2912 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2913 rare situations a different rule is selected --- notably nested tuple
  2914 elimination instead of former prod.exhaust: use explicit (case_tac t
  2915 rule: prod.exhaust) here.
  2916 
  2917 * Attributes "cases", "induct", "coinduct" support "del" option.
  2918 
  2919 * Removed fact "case_split_thm", which duplicates "case_split".
  2920 
  2921 * The option datatype has been moved to a new theory Option.  Renamed
  2922 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2923 
  2924 * New predicate "strict_mono" classifies strict functions on partial
  2925 orders.  With strict functions on linear orders, reasoning about
  2926 (in)equalities is facilitated by theorems "strict_mono_eq",
  2927 "strict_mono_less_eq" and "strict_mono_less".
  2928 
  2929 * Some set operations are now proper qualified constants with
  2930 authentic syntax.  INCOMPATIBILITY:
  2931 
  2932     op Int ~>   Set.Int
  2933     op Un ~>    Set.Un
  2934     INTER ~>    Set.INTER
  2935     UNION ~>    Set.UNION
  2936     Inter ~>    Set.Inter
  2937     Union ~>    Set.Union
  2938     {} ~>       Set.empty
  2939     UNIV ~>     Set.UNIV
  2940 
  2941 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2942 theory Set.
  2943 
  2944 * Auxiliary class "itself" has disappeared -- classes without any
  2945 parameter are treated as expected by the 'class' command.
  2946 
  2947 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2948 
  2949 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2950 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2951 
  2952 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2953 method "approximation".  It proves formulas on real values by using
  2954 interval arithmetic.  In the formulas are also the transcendental
  2955 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2956 allowed. For examples see
  2957 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2958 
  2959 * Theory "Reflection" now resides in HOL/Library.
  2960 
  2961 * Entry point to Word library now simply named "Word".
  2962 INCOMPATIBILITY.
  2963 
  2964 * Made source layout more coherent with logical distribution
  2965 structure:
  2966 
  2967     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2968     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2969     src/HOL/Library/GCD.thy ~> src/HOL/
  2970     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2971     src/HOL/Library/Parity.thy ~> src/HOL/
  2972     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2973     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2974     src/HOL/Real/Lubs.thy ~> src/HOL/
  2975     src/HOL/Real/PReal.thy ~> src/HOL/
  2976     src/HOL/Real/Rational.thy ~> src/HOL/
  2977     src/HOL/Real/RComplete.thy ~> src/HOL/
  2978     src/HOL/Real/RealDef.thy ~> src/HOL/
  2979     src/HOL/Real/RealPow.thy ~> src/HOL/
  2980     src/HOL/Real/Real.thy ~> src/HOL/
  2981     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2982     src/HOL/Complex/Complex.thy ~> src/HOL/
  2983     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2984     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2985     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2986     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2987     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2988     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2989     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2990     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2991     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2992     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2993     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2994     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2995     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2996     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2997     src/HOL/Real/Float ~> src/HOL/Library/
  2998     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2999     src/HOL/Real/RealVector.thy ~> src/HOL/
  3000 
  3001     src/HOL/arith_data.ML ~> src/HOL/Tools
  3002     src/HOL/hologic.ML ~> src/HOL/Tools
  3003     src/HOL/simpdata.ML ~> src/HOL/Tools
  3004     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  3005     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  3006     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  3007     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  3008     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  3009     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  3010     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  3011 
  3012     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3013     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3014     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3015     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3016     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3017     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3018 
  3019 * If methods "eval" and "evaluation" encounter a structured proof
  3020 state with !!/==>, only the conclusion is evaluated to True (if
  3021 possible), avoiding strange error messages.
  3022 
  3023 * Method "sizechange" automates termination proofs using (a
  3024 modification of) the size-change principle.  Requires SAT solver.  See
  3025 src/HOL/ex/Termination.thy for examples.
  3026 
  3027 * Simplifier: simproc for let expressions now unfolds if bound
  3028 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3029 
  3030 * Method "arith": Linear arithmetic now ignores all inequalities when
  3031 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3032 
  3033 * New attribute "arith" for facts that should always be used
  3034 automatically by arithmetic. It is intended to be used locally in
  3035 proofs, e.g.
  3036 
  3037   assumes [arith]: "x > 0"
  3038 
  3039 Global usage is discouraged because of possible performance impact.
  3040 
  3041 * New classes "top" and "bot" with corresponding operations "top" and
  3042 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3043 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3044 
  3045 * Changed definition lemma "less_fun_def" in order to provide an
  3046 instance for preorders on functions; use lemma "less_le" instead.
  3047 INCOMPATIBILITY.
  3048 
  3049 * Theory Orderings: class "wellorder" moved here, with explicit
  3050 induction rule "less_induct" as assumption.  For instantiation of
  3051 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3052 INCOMPATIBILITY.
  3053 
  3054 * Theory Orderings: added class "preorder" as superclass of "order".
  3055 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3056 etc. slightly changed.  Some theorems named order_class.* now named
  3057 preorder_class.*.
  3058 
  3059 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3060 "diag" to "Id_on".
  3061 
  3062 * Theory Finite_Set: added a new fold combinator of type
  3063 
  3064   ('a => 'b => 'b) => 'b => 'a set => 'b
  3065 
  3066 Occasionally this is more convenient than the old fold combinator
  3067 which is now defined in terms of the new one and renamed to
  3068 fold_image.
  3069 
  3070 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3071 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3072 extended with further lemmas!).  At the moment both still exist but
  3073 the former will disappear at some point.
  3074 
  3075 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3076 class recpower.  Type-specific simp rules for various recpower types
  3077 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3078 
  3079 rat_power_0    -> power_0
  3080 rat_power_Suc  -> power_Suc
  3081 realpow_0      -> power_0
  3082 realpow_Suc    -> power_Suc
  3083 complexpow_0   -> power_0
  3084 complexpow_Suc -> power_Suc
  3085 power_poly_0   -> power_0
  3086 power_poly_Suc -> power_Suc
  3087 
  3088 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3089 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3090 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3091 of lemmas from Divides has been generalized from nat to class
  3092 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3093 renames resulting from duplicate elimination:
  3094 
  3095     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3096     zero_dvd_iff ~>         dvd_0_left_iff
  3097     dvd_0 ~>                dvd_0_right
  3098     DIVISION_BY_ZERO_DIV ~> div_by_0
  3099     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3100     mult_div ~>             div_mult_self2_is_id
  3101     mult_mod ~>             mod_mult_self2_is_0
  3102 
  3103 * Theory IntDiv: removed many lemmas that are instances of class-based
  3104 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3105 rename old lemmas as follows:
  3106 
  3107 dvd_diff               -> nat_dvd_diff
  3108 dvd_zminus_iff         -> dvd_minus_iff
  3109 mod_add1_eq            -> mod_add_eq
  3110 mod_mult1_eq           -> mod_mult_right_eq
  3111 mod_mult1_eq'          -> mod_mult_left_eq
  3112 mod_mult_distrib_mod   -> mod_mult_eq
  3113 nat_mod_add_left_eq    -> mod_add_left_eq
  3114 nat_mod_add_right_eq   -> mod_add_right_eq
  3115 nat_mod_div_trivial    -> mod_div_trivial
  3116 nat_mod_mod_trivial    -> mod_mod_trivial
  3117 zdiv_zadd_self1        -> div_add_self1
  3118 zdiv_zadd_self2        -> div_add_self2
  3119 zdiv_zmult_self1       -> div_mult_self2_is_id
  3120 zdiv_zmult_self2       -> div_mult_self1_is_id
  3121 zdvd_triv_left         -> dvd_triv_left
  3122 zdvd_triv_right        -> dvd_triv_right
  3123 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3124 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3125 zmod_zadd_left_eq      -> mod_add_left_eq
  3126 zmod_zadd_right_eq     -> mod_add_right_eq
  3127 zmod_zadd_self1        -> mod_add_self1
  3128 zmod_zadd_self2        -> mod_add_self2
  3129 zmod_zadd1_eq          -> mod_add_eq
  3130 zmod_zdiff1_eq         -> mod_diff_eq
  3131 zmod_zdvd_zmod         -> mod_mod_cancel
  3132 zmod_zmod_cancel       -> mod_mod_cancel
  3133 zmod_zmult_self1       -> mod_mult_self2_is_0
  3134 zmod_zmult_self2       -> mod_mult_self1_is_0
  3135 zmod_1                 -> mod_by_1
  3136 zdiv_1                 -> div_by_1
  3137 zdvd_abs1              -> abs_dvd_iff
  3138 zdvd_abs2              -> dvd_abs_iff
  3139 zdvd_refl              -> dvd_refl
  3140 zdvd_trans             -> dvd_trans
  3141 zdvd_zadd              -> dvd_add
  3142 zdvd_zdiff             -> dvd_diff
  3143 zdvd_zminus_iff        -> dvd_minus_iff
  3144 zdvd_zminus2_iff       -> minus_dvd_iff
  3145 zdvd_zmultD            -> dvd_mult_right
  3146 zdvd_zmultD2           -> dvd_mult_left
  3147 zdvd_zmult_mono        -> mult_dvd_mono
  3148 zdvd_0_right           -> dvd_0_right
  3149 zdvd_0_left            -> dvd_0_left_iff
  3150 zdvd_1_left            -> one_dvd
  3151 zminus_dvd_iff         -> minus_dvd_iff
  3152 
  3153 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3154 
  3155 * The real numbers offer decimal input syntax: 12.34 is translated
  3156 into 1234/10^2. This translation is not reversed upon output.
  3157 
  3158 * Theory Library/Polynomial defines an abstract type 'a poly of
  3159 univariate polynomials with coefficients of type 'a.  In addition to
  3160 the standard ring operations, it also supports div and mod.  Code
  3161 generation is also supported, using list-style constructors.
  3162 
  3163 * Theory Library/Inner_Product defines a class of real_inner for real
  3164 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3165 => real.  Class real_inner is a subclass of real_normed_vector from
  3166 theory RealVector.
  3167 
  3168 * Theory Library/Product_Vector provides instances for the product
  3169 type 'a * 'b of several classes from RealVector and Inner_Product.
  3170 Definitions of addition, subtraction, scalar multiplication, norms,
  3171 and inner products are included.
  3172 
  3173 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3174 addition to the field operations, numerals and case syntax are also
  3175 supported.
  3176 
  3177 * Theory Library/Diagonalize provides constructive version of Cantor's
  3178 first diagonalization argument.
  3179 
  3180 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3181 zlcm (for int); carried together from various gcd/lcm developements in
  3182 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3183 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3184 may recover tupled syntax as follows:
  3185 
  3186     hide (open) const gcd
  3187     abbreviation gcd where
  3188       "gcd == (%(a, b). GCD.gcd a b)"
  3189     notation (output)
  3190       GCD.gcd ("gcd '(_, _')")
  3191 
  3192 The same works for lcm, zgcd, zlcm.
  3193 
  3194 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3195 instantiations for algebraic structures.  Removed some duplicate
  3196 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3197 
  3198 * ML antiquotation @{code} takes a constant as argument and generates
  3199 corresponding code in background and inserts name of the corresponding
  3200 resulting ML value/function/datatype constructor binding in place.
  3201 All occurrences of @{code} with a single ML block are generated
  3202 simultaneously.  Provides a generic and safe interface for
  3203 instrumentalizing code generation.  See
  3204 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3205 In future you ought to refrain from ad-hoc compiling generated SML
  3206 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3207 cannot refer to constants for which user-defined serializations are
  3208 set.  Refer to the corresponding ML counterpart directly in that
  3209 cases.
  3210 
  3211 * Command 'rep_datatype': instead of theorem names the command now
  3212 takes a list of terms denoting the constructors of the type to be
  3213 represented as datatype.  The characteristic theorems have to be
  3214 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3215 have disappeared in favour of existing ones:
  3216 
  3217     unit_induct                 ~> unit.induct
  3218     prod_induct                 ~> prod.induct
  3219     sum_induct                  ~> sum.induct
  3220     Suc_Suc_eq                  ~> nat.inject
  3221     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3222 
  3223 
  3224 *** HOL-Algebra ***
  3225 
  3226 * New locales for orders and lattices where the equivalence relation
  3227 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3228 locales use a record structure with field eq for the equivalence.
  3229 
  3230 * New theory of factorial domains.
  3231 
  3232 * Units_l_inv and Units_r_inv are now simp rules by default.
  3233 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3234 and/or r_inv will now also require deletion of these lemmas.
  3235 
  3236 * Renamed the following theorems, INCOMPATIBILITY:
  3237 
  3238 UpperD ~> Upper_memD
  3239 LowerD ~> Lower_memD
  3240 least_carrier ~> least_closed
  3241 greatest_carrier ~> greatest_closed
  3242 greatest_Lower_above ~> greatest_Lower_below
  3243 one_zero ~> carrier_one_zero
  3244 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3245 
  3246 
  3247 *** HOL-Nominal ***
  3248 
  3249 * Nominal datatypes can now contain type-variables.
  3250 
  3251 * Commands 'nominal_inductive' and 'equivariance' work with local
  3252 theory targets.
  3253 
  3254 * Nominal primrec can now works with local theory targets and its
  3255 specification syntax now conforms to the general format as seen in
  3256 'inductive' etc.
  3257 
  3258 * Method "perm_simp" honours the standard simplifier attributes
  3259 (no_asm), (no_asm_use) etc.
  3260 
  3261 * The new predicate #* is defined like freshness, except that on the
  3262 left hand side can be a set or list of atoms.
  3263 
  3264 * Experimental command 'nominal_inductive2' derives strong induction
  3265 principles for inductive definitions.  In contrast to
  3266 'nominal_inductive', which can only deal with a fixed number of
  3267 binders, it can deal with arbitrary expressions standing for sets of
  3268 atoms to be avoided.  The only inductive definition we have at the
  3269 moment that needs this generalisation is the typing rule for Lets in
  3270 the algorithm W:
  3271 
  3272  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3273  -----------------------------------------------------------------
  3274          Gamma |- Let x be t1 in t2 : T2
  3275 
  3276 In this rule one wants to avoid all the binders that are introduced by
  3277 "close Gamma T1".  We are looking for other examples where this
  3278 feature might be useful.  Please let us know.
  3279 
  3280 
  3281 *** HOLCF ***
  3282 
  3283 * Reimplemented the simplification procedure for proving continuity
  3284 subgoals.  The new simproc is extensible; users can declare additional
  3285 continuity introduction rules with the attribute [cont2cont].
  3286 
  3287 * The continuity simproc now uses a different introduction rule for
  3288 solving continuity subgoals on terms with lambda abstractions.  In
  3289 some rare cases the new simproc may fail to solve subgoals that the
  3290 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3291 Potential INCOMPATIBILITY.
  3292 
  3293 * Command 'fixrec': specification syntax now conforms to the general
  3294 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3295 examples.  INCOMPATIBILITY.
  3296 
  3297 
  3298 *** ZF ***
  3299 
  3300 * Proof of Zorn's Lemma for partial orders.
  3301 
  3302 
  3303 *** ML ***
  3304 
  3305 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3306 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3307 depends on multithreading, so timouts will not work before Poly/ML
  3308 5.2.1!
  3309 
  3310 * High-level support for concurrent ML programming, see
  3311 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3312 particularly convenient to organize independent functional
  3313 computations.  The concept of "synchronized variables" provides a
  3314 higher-order interface for components with shared state, avoiding the
  3315 delicate details of mutexes and condition variables.  (Requires
  3316 Poly/ML 5.2.1 or later.)
  3317 
  3318 * ML bindings produced via Isar commands are stored within the Isar
  3319 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3320 become thread-safe and work with undo as expected (concerning
  3321 top-level bindings, not side-effects on global references).
  3322 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3323 compiler at runtime; really global bindings need to be given outside a
  3324 theory.  (Requires Poly/ML 5.2 or later.)
  3325 
  3326 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3327 context.  Top-level ML bindings are stored within the proof context in
  3328 a purely sequential fashion, disregarding the nested proof structure.
  3329 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3330 proof.  (Requires Poly/ML 5.2 or later.)
  3331 
  3332 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3333 and Method.setup, as well as Isar commands 'attribute_setup' and
  3334 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3335 existing code accordingly, or use plain 'setup' together with old
  3336 Method.add_method.
  3337 
  3338 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3339 to 'a -> thm, while results are always tagged with an authentic oracle
  3340 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3341 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3342 accordingly.  Note that extra performance may be gained by producing
  3343 the cterm carefully, avoiding slow Thm.cterm_of.
  3344 
  3345 * Simplified interface for defining document antiquotations via
  3346 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3347 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3348 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3349 examples.
  3350 
  3351 * More systematic treatment of long names, abstract name bindings, and
  3352 name space operations.  Basic operations on qualified names have been
  3353 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3354 Long_Name.append.  Old type bstring has been mostly replaced by
  3355 abstract type binding (see structure Binding), which supports precise
  3356 qualification by packages and local theory targets, as well as proper
  3357 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3358 bstring values into Binding.name, or better pass through abstract
  3359 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3360 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3361 
  3362 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3363 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3364 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3365 
  3366 * Disposed old type and term read functions (Sign.read_def_typ,
  3367 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3368 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3369 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3370 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3371 resort for legacy applications.
  3372 
  3373 * Disposed old declarations, tactics, tactic combinators that refer to
  3374 the simpset or claset of an implicit theory (such as Addsimps,
  3375 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3376 embedded ML text, or local_simpset_of with a proper context passed as
  3377 explicit runtime argument.
  3378 
  3379 * Rules and tactics that read instantiations (read_instantiate,
  3380 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3381 context, which is required for parsing and type-checking.  Moreover,
  3382 the variables are specified as plain indexnames, not string encodings
  3383 thereof.  INCOMPATIBILITY.
  3384 
  3385 * Generic Toplevel.add_hook interface allows to analyze the result of
  3386 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3387 for theorem dependency output of transactions resulting in a new
  3388 theory state.
  3389 
  3390 * ML antiquotations: block-structured compilation context indicated by
  3391 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3392 
  3393   @{binding name}                         - basic name binding
  3394   @{let ?pat = term}                      - term abbreviation (HO matching)
  3395   @{note name = fact}                     - fact abbreviation
  3396   @{thm fact}                             - singleton fact (with attributes)
  3397   @{thms fact}                            - general fact (with attributes)
  3398   @{lemma prop by method}                 - singleton goal
  3399   @{lemma prop by meth1 meth2}            - singleton goal
  3400   @{lemma prop1 ... propN by method}      - general goal
  3401   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3402   @{lemma (open) ...}                     - open derivation
  3403 
  3404 
  3405 *** System ***
  3406 
  3407 * The Isabelle "emacs" tool provides a specific interface to invoke
  3408 Proof General / Emacs, with more explicit failure if that is not
  3409 installed (the old isabelle-interface script silently falls back on
  3410 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3411 installation location of the Proof General distribution.
  3412 
  3413 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3414 the Isabelle process into a JVM/Scala application.  See
  3415 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3416 process wrapper has been discontinued.)
  3417 
  3418 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3419 
  3420 * Various status messages (with exact source position information) are
  3421 emitted, if proper markup print mode is enabled.  This allows
  3422 user-interface components to provide detailed feedback on internal
  3423 prover operations.
  3424 
  3425 
  3426 
  3427 New in Isabelle2008 (June 2008)
  3428 -------------------------------
  3429 
  3430 *** General ***
  3431 
  3432 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3433 and updated, with formally checked references as hyperlinks.
  3434 
  3435 * Theory loader: use_thy (and similar operations) no longer set the
  3436 implicit ML context, which was occasionally hard to predict and in
  3437 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3438 provides a proper context already.
  3439 
  3440 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3441 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3442 'use' within a theory file will do the job.
  3443 
  3444 * Name space merge now observes canonical order, i.e. the second space
  3445 is inserted into the first one, while existing entries in the first
  3446 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3447 swap theory imports.
  3448 
  3449 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3450 INCOMPATIBILITY in identifier syntax etc.
  3451 
  3452 * Outer syntax: string tokens no longer admit escaped white space,
  3453 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3454 white space without escapes.
  3455 
  3456 * Outer syntax: string tokens may contain arbitrary character codes
  3457 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3458 "foo_bar".
  3459 
  3460 
  3461 *** Pure ***
  3462 
  3463 * Context-dependent token translations.  Default setup reverts locally
  3464 fixed variables, and adds hilite markup for undeclared frees.
  3465 
  3466 * Unused theorems can be found using the new command 'unused_thms'.
  3467 There are three ways of invoking it:
  3468 
  3469 (1) unused_thms
  3470      Only finds unused theorems in the current theory.
  3471 
  3472 (2) unused_thms thy_1 ... thy_n -
  3473      Finds unused theorems in the current theory and all of its ancestors,
  3474      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3475 
  3476 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3477      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3478      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3479      their ancestors.
  3480 
  3481 In order to increase the readability of the list produced by
  3482 unused_thms, theorems that have been created by a particular instance
  3483 of a theory command such as 'inductive' or 'function' are considered
  3484 to belong to the same "group", meaning that if at least one theorem in
  3485 this group is used, the other theorems in the same group are no longer
  3486 reported as unused.  Moreover, if all theorems in the group are
  3487 unused, only one theorem in the group is displayed.
  3488 
  3489 Note that proof objects have to be switched on in order for
  3490 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3491 usually the case when using Proof General with the default settings).
  3492 
  3493 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3494 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3495 duplicate fact bindings, or even accidental fact duplications.  Note
  3496 that tools may maintain dynamically scoped facts systematically, using
  3497 PureThy.add_thms_dynamic.
  3498 
  3499 * Command 'hide' now allows to hide from "fact" name space as well.
  3500 
  3501 * Eliminated destructive theorem database, simpset, claset, and
  3502 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3503 update of theories within ML code.
  3504 
  3505 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3506 INCOMPATIBILITY, object-logics depending on former Pure require
  3507 additional setup PureThy.old_appl_syntax_setup; object-logics
  3508 depending on former CPure need to refer to Pure.
  3509 
  3510 * Commands 'use' and 'ML' are now purely functional, operating on
  3511 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3512 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3513 INCOMPATIBILITY.
  3514 
  3515 * Command 'setup': discontinued implicit version with ML reference.
  3516 
  3517 * Instantiation target allows for simultaneous specification of class
  3518 instance operations together with an instantiation proof.
  3519 Type-checking phase allows to refer to class operations uniformly.
  3520 See src/HOL/Complex/Complex.thy for an Isar example and
  3521 src/HOL/Library/Eval.thy for an ML example.
  3522 
  3523 * Indexing of literal facts: be more serious about including only
  3524 facts from the visible specification/proof context, but not the
  3525 background context (locale etc.).  Affects `prop` notation and method
  3526 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3527 situations.
  3528 
  3529 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3530 "(open)" option, which used to expose internal bound variables to the
  3531 proof text.
  3532 
  3533 * Isar statements: removed obsolete case "rule_context".
  3534 INCOMPATIBILITY, better use explicit fixes/assumes.
  3535 
  3536 * Locale proofs: default proof step now includes 'unfold_locales';
  3537 hence 'proof' without argument may be used to unfold locale
  3538 predicates.
  3539 
  3540 
  3541 *** Document preparation ***
  3542 
  3543 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3544 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3545 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3546 spot); renamed link color from "darkblue" to "linkcolor" (default
  3547 value unchanged, can be redefined via \definecolor); no longer sets
  3548 "a4paper" option (unnecessary or even intrusive).
  3549 
  3550 * Antiquotation @{lemma A method} proves proposition A by the given
  3551 method (either a method name or a method name plus (optional) method
  3552 arguments in parentheses) and prints A just like @{prop A}.
  3553 
  3554 
  3555 *** HOL ***
  3556 
  3557 * New primrec package.  Specification syntax conforms in style to
  3558 definition/function/....  No separate induction rule is provided.  The
  3559 "primrec" command distinguishes old-style and new-style specifications
  3560 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3561 When adjusting theories, beware: constants stemming from new-style
  3562 primrec specifications have authentic syntax.
  3563 
  3564 * Metis prover is now an order of magnitude faster, and also works
  3565 with multithreading.
  3566 
  3567 * Metis: the maximum number of clauses that can be produced from a
  3568 theorem is now given by the attribute max_clauses.  Theorems that
  3569 exceed this number are ignored, with a warning printed.
  3570 
  3571 * Sledgehammer no longer produces structured proofs by default. To
  3572 enable, declare [[sledgehammer_full = true]].  Attributes
  3573 reconstruction_modulus, reconstruction_sorts renamed
  3574 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3575 
  3576 * Method "induct_scheme" derives user-specified induction rules
  3577 from well-founded induction and completeness of patterns. This factors
  3578 out some operations that are done internally by the function package
  3579 and makes them available separately.  See
  3580 src/HOL/ex/Induction_Scheme.thy for examples.
  3581 
  3582 * More flexible generation of measure functions for termination
  3583 proofs: Measure functions can be declared by proving a rule of the
  3584 form "is_measure f" and giving it the [measure_function] attribute.
  3585 The "is_measure" predicate is logically meaningless (always true), and
  3586 just guides the heuristic.  To find suitable measure functions, the
  3587 termination prover sets up the goal "is_measure ?f" of the appropriate
  3588 type and generates all solutions by prolog-style backwards proof using
  3589 the declared rules.
  3590 
  3591 This setup also deals with rules like 
  3592 
  3593   "is_measure f ==> is_measure (list_size f)"
  3594 
  3595 which accommodates nested datatypes that recurse through lists.
  3596 Similar rules are predeclared for products and option types.
  3597 
  3598 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3599 
  3600   INCOMPATIBILITIES:
  3601 
  3602   - Definitions of overloaded constants on sets have to be replaced by
  3603     definitions on => and bool.
  3604 
  3605   - Some definitions of overloaded operators on sets can now be proved
  3606     using the definitions of the operators on => and bool.  Therefore,
  3607     the following theorems have been renamed:
  3608 
  3609       subset_def   -> subset_eq
  3610       psubset_def  -> psubset_eq
  3611       set_diff_def -> set_diff_eq
  3612       Compl_def    -> Compl_eq
  3613       Sup_set_def  -> Sup_set_eq
  3614       Inf_set_def  -> Inf_set_eq
  3615       sup_set_def  -> sup_set_eq
  3616       inf_set_def  -> inf_set_eq
  3617 
  3618   - Due to the incompleteness of the HO unification algorithm, some
  3619     rules such as subst may require manual instantiation, if some of
  3620     the unknowns in the rule is a set.
  3621 
  3622   - Higher order unification and forward proofs:
  3623     The proof pattern
  3624 
  3625       have "P (S::'a set)" <...>
  3626       then have "EX S. P S" ..
  3627 
  3628     no longer works (due to the incompleteness of the HO unification
  3629     algorithm) and must be replaced by the pattern
  3630 
  3631       have "EX S. P S"
  3632       proof
  3633         show "P S" <...>
  3634       qed
  3635 
  3636   - Calculational reasoning with subst (or similar rules):
  3637     The proof pattern
  3638 
  3639       have "P (S::'a set)" <...>
  3640       also have "S = T" <...>
  3641       finally have "P T" .
  3642 
  3643     no longer works (for similar reasons as the previous example) and
  3644     must be replaced by something like
  3645 
  3646       have "P (S::'a set)" <...>
  3647       moreover have "S = T" <...>
  3648       ultimately have "P T" by simp
  3649 
  3650   - Tactics or packages written in ML code:
  3651     Code performing pattern matching on types via
  3652 
  3653       Type ("set", [T]) => ...
  3654 
  3655     must be rewritten. Moreover, functions like strip_type or
  3656     binder_types no longer return the right value when applied to a
  3657     type of the form
  3658 
  3659       T1 => ... => Tn => U => bool
  3660 
  3661     rather than
  3662 
  3663       T1 => ... => Tn => U set
  3664 
  3665 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3666 Wellfounded_Relations to theory Wellfounded.
  3667 
  3668 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3669 
  3670 * Class finite no longer treats UNIV as class parameter.  Use class
  3671 enum from theory Library/Enum instead to achieve a similar effect.
  3672 INCOMPATIBILITY.
  3673 
  3674 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3675 and "Cons".  INCOMPATIBILITY.
  3676 
  3677 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3678 Potential INCOMPATIBILITY.
  3679 
  3680 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3681 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3682 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3683 
  3684 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3685 the same name in theory Orderings:
  3686 
  3687   less_trans
  3688   less_linear
  3689   le_imp_less_or_eq
  3690   le_less_trans
  3691   less_le_trans
  3692   less_not_sym
  3693   less_asym
  3694 
  3695 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3696 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3697 and different variable names.
  3698 
  3699 * Library/Option_ord.thy: Canonical order on option type.
  3700 
  3701 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3702 finite maps.
  3703 
  3704 * Library/Countable.thy: Type class for countable types.
  3705 
  3706 * Theory Int: The representation of numerals has changed.  The infix
  3707 operator BIT and the bit datatype with constructors B0 and B1 have
  3708 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3709 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3710 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3711 accordingly.
  3712 
  3713 * Theory Nat: definition of <= and < on natural numbers no longer
  3714 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3715 le_def and less_def have disappeared.  Consider lemmas not_less
  3716 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3717 
  3718 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3719 (whose purpose mainly is for various fold_set functionals) have been
  3720 abandoned in favor of the existing algebraic classes
  3721 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3722 lower_semilattice (resp. upper_semilattice) and linorder.
  3723 INCOMPATIBILITY.
  3724 
  3725 * Theory Transitive_Closure: induct and cases rules now declare proper
  3726 case_names ("base" and "step").  INCOMPATIBILITY.
  3727 
  3728 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3729 lattices.  The form set-specific version is available as
  3730 Inductive.lfp_ordinal_induct_set.
  3731 
  3732 * Renamed theorems "power.simps" to "power_int.simps".
  3733 INCOMPATIBILITY.
  3734 
  3735 * Class semiring_div provides basic abstract properties of semirings
  3736 with division and modulo operations.  Subsumes former class dvd_mod.
  3737 
  3738 * Merged theories IntDef, Numeral and IntArith into unified theory
  3739 Int.  INCOMPATIBILITY.
  3740 
  3741 * Theory Library/Code_Index: type "index" now represents natural
  3742 numbers rather than integers.  INCOMPATIBILITY.
  3743 
  3744 * New class "uminus" with operation "uminus" (split of from class
  3745 "minus" which now only has operation "minus", binary).
  3746 INCOMPATIBILITY.
  3747 
  3748 * Constants "card", "internal_split", "option_map" now with authentic
  3749 syntax.  INCOMPATIBILITY.
  3750 
  3751 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3752 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3753 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3754 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3755 Sup_set_def, le_def, less_def, option_map_def now with object
  3756 equality.  INCOMPATIBILITY.
  3757 
  3758 * Records. Removed K_record, and replaced it by pure lambda term
  3759 %x. c. The simplifier setup is now more robust against eta expansion.
  3760 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3761 
  3762 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3763 
  3764 * Library/ListVector: new theory of arithmetic vector operations.
  3765 
  3766 * Library/Order_Relation: new theory of various orderings as sets of
  3767 pairs.  Defines preorders, partial orders, linear orders and
  3768 well-orders on sets and on types.
  3769 
  3770 
  3771 *** ZF ***
  3772 
  3773 * Renamed some theories to allow to loading both ZF and HOL in the
  3774 same session:
  3775 
  3776   Datatype  -> Datatype_ZF
  3777   Inductive -> Inductive_ZF
  3778   Int       -> Int_ZF
  3779   IntDiv    -> IntDiv_ZF
  3780   Nat       -> Nat_ZF
  3781   List      -> List_ZF
  3782   Main      -> Main_ZF
  3783 
  3784 INCOMPATIBILITY: ZF theories that import individual theories below
  3785 Main might need to be adapted.  Regular theory Main is still
  3786 available, as trivial extension of Main_ZF.
  3787 
  3788 
  3789 *** ML ***
  3790 
  3791 * ML within Isar: antiquotation @{const name} or @{const
  3792 name(typargs)} produces statically-checked Const term.
  3793 
  3794 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3795 (of the same name).  Removed obsolete print command.
  3796 
  3797 * Removed obsolete "use_legacy_bindings" function.
  3798 
  3799 * The ``print mode'' is now a thread-local value derived from a global
  3800 template (the former print_mode reference), thus access becomes
  3801 non-critical.  The global print_mode reference is for session
  3802 management only; user-code should use print_mode_value,
  3803 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3804 
  3805 * Functions system/system_out provide a robust way to invoke external
  3806 shell commands, with propagation of interrupts (requires Poly/ML
  3807 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3808 
  3809 
  3810 *** System ***
  3811 
  3812 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3813 in accordance with Proof General 3.7, which prefers GNU emacs.
  3814 
  3815 * isatool tty runs Isabelle process with plain tty interaction;
  3816 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3817 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3818 
  3819 * isatool browser now works with Cygwin as well, using general
  3820 "javapath" function defined in Isabelle process environment.
  3821 
  3822 * YXML notation provides a simple and efficient alternative to
  3823 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3824 isatool yxml as described in the Isabelle system manual.
  3825 
  3826 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3827 provides general wrapper for managing an Isabelle process in a robust
  3828 fashion, with ``cooked'' output from stdin/stderr.
  3829 
  3830 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3831 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3832 
  3833 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3834 way of changing the user's settings is via
  3835 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3836 script.
  3837 
  3838 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3839 cores of the underlying machine, which is a good starting point for
  3840 optimal performance tuning.  The corresponding usedir option -M allows
  3841 "max" as an alias for "0".  WARNING: does not work on certain versions
  3842 of Mac OS (with Poly/ML 5.1).
  3843 
  3844 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3845 adverse effect of Isabelle flooding interactive front-ends (notably
  3846 ProofGeneral / XEmacs).
  3847 
  3848 
  3849 
  3850 New in Isabelle2007 (November 2007)
  3851 -----------------------------------
  3852 
  3853 *** General ***
  3854 
  3855 * More uniform information about legacy features, notably a
  3856 warning/error of "Legacy feature: ...", depending on the state of the
  3857 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3858 legacy features will disappear eventually.
  3859 
  3860 * Theory syntax: the header format ``theory A = B + C:'' has been
  3861 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3862 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3863 
  3864 * Theory syntax: the old non-Isar theory file format has been
  3865 discontinued altogether.  Note that ML proof scripts may still be used
  3866 with Isar theories; migration is usually quite simple with the ML
  3867 function use_legacy_bindings.  INCOMPATIBILITY.
  3868 
  3869 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3870 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3871 quotes.
  3872 
  3873 * Theory loader: be more serious about observing the static theory
  3874 header specifications (including optional directories), but not the
  3875 accidental file locations of previously successful loads.  The strict
  3876 update policy of former update_thy is now already performed by
  3877 use_thy, so the former has been removed; use_thys updates several
  3878 theories simultaneously, just as 'imports' within a theory header
  3879 specification, but without merging the results.  Potential
  3880 INCOMPATIBILITY: may need to refine theory headers and commands
  3881 ROOT.ML which depend on load order.
  3882 
  3883 * Theory loader: optional support for content-based file
  3884 identification, instead of the traditional scheme of full physical
  3885 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3886 (cf. the system manual).  The new scheme allows to work with
  3887 non-finished theories in persistent session images, such that source
  3888 files may be moved later on without requiring reloads.
  3889 
  3890 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3891 file (with the same base name as the theory) are considered a legacy
  3892 feature, which will disappear eventually. Even now, the theory loader
  3893 no longer maintains dependencies on such files.
  3894 
  3895 * Syntax: the scope for resolving ambiguities via type-inference is
  3896 now limited to individual terms, instead of whole simultaneous
  3897 specifications as before. This greatly reduces the complexity of the
  3898 syntax module and improves flexibility by separating parsing and
  3899 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3900 'fixes' etc.) are required in rare situations.
  3901 
  3902 * Syntax: constants introduced by new-style packages ('definition',
  3903 'abbreviation' etc.) are passed through the syntax module in
  3904 ``authentic mode''. This means that associated mixfix annotations
  3905 really stick to such constants, independently of potential name space
  3906 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3907 trees are represented slightly differently, may need to adapt syntax
  3908 translations accordingly. Use CONST marker in 'translations' and
  3909 @{const_syntax} antiquotation in 'parse_translation' etc.
  3910 
  3911 * Legacy goal package: reduced interface to the bare minimum required
  3912 to keep existing proof scripts running.  Most other user-level
  3913 functions are now part of the OldGoals structure, which is *not* open
  3914 by default (consider isatool expandshort before open OldGoals).
  3915 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3916 these tend to cause confusion about the actual goal (!) context being
  3917 used here, which is not necessarily the same as the_context().
  3918 
  3919 * Command 'find_theorems': supports "*" wild-card in "name:"
  3920 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3921 support a specific search form (see ProofGeneral/CHANGES).
  3922 
  3923 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3924 by default, which means that "prems" (and also "fixed variables") are
  3925 suppressed from proof state output.  Note that the ProofGeneral
  3926 settings mechanism allows to change and save options persistently, but
  3927 older versions of Isabelle will fail to start up if a negative prems
  3928 limit is imposed.
  3929 
  3930 * Local theory targets may be specified by non-nested blocks of
  3931 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3932 contain definitions, theorems etc., including any derived mechanism
  3933 that has been implemented on top of these primitives.  This concept
  3934 generalizes the existing ``theorem (in ...)'' towards more versatility
  3935 and scalability.
  3936 
  3937 * Proof General interface: proper undo of final 'end' command;
  3938 discontinued Isabelle/classic mode (ML proof scripts).
  3939 
  3940 
  3941 *** Document preparation ***
  3942 
  3943 * Added antiquotation @{theory name} which prints the given name,
  3944 after checking that it refers to a valid ancestor theory in the
  3945 current context.
  3946 
  3947 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3948 check the given source text as ML type/structure, printing verbatim.
  3949 
  3950 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3951 "c args == rhs" given in the current context.  (Any number of
  3952 arguments may be given on the LHS.)
  3953 
  3954 
  3955 *** Pure ***
  3956 
  3957 * The 'class' package offers a combination of axclass and locale to
  3958 achieve Haskell-like type classes in Isabelle.  Definitions and
  3959 theorems within a class context produce both relative results (with
  3960 implicit parameters according to the locale context), and polymorphic
  3961 constants with qualified polymorphism (according to the class
  3962 context).  Within the body context of a 'class' target, a separate
  3963 syntax layer ("user space type system") takes care of converting
  3964 between global polymorphic consts and internal locale representation.
  3965 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3966 "isatool doc classes" provides a tutorial.
  3967 
  3968 * Generic code generator framework allows to generate executable
  3969 code for ML and Haskell (including Isabelle classes).  A short usage
  3970 sketch:
  3971 
  3972     internal compilation:
  3973         export_code <list of constants (term syntax)> in SML
  3974     writing SML code to a file:
  3975         export_code <list of constants (term syntax)> in SML <filename>
  3976     writing OCaml code to a file:
  3977         export_code <list of constants (term syntax)> in OCaml <filename>
  3978     writing Haskell code to a bunch of files:
  3979         export_code <list of constants (term syntax)> in Haskell <filename>
  3980 
  3981     evaluating closed propositions to True/False using code generation:
  3982         method ``eval''
  3983 
  3984 Reasonable default setup of framework in HOL.
  3985 
  3986 Theorem attributs for selecting and transforming function equations theorems:
  3987 
  3988     [code fun]:        select a theorem as function equation for a specific constant
  3989     [code fun del]:    deselect a theorem as function equation for a specific constant
  3990     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3991     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3992 
  3993 User-defined serializations (target in {SML, OCaml, Haskell}):
  3994 
  3995     code_const <and-list of constants (term syntax)>
  3996       {(target) <and-list of const target syntax>}+
  3997 
  3998     code_type <and-list of type constructors>
  3999       {(target) <and-list of type target syntax>}+
  4000 
  4001     code_instance <and-list of instances>
  4002       {(target)}+
  4003         where instance ::= <type constructor> :: <class>
  4004 
  4005     code_class <and_list of classes>
  4006       {(target) <and-list of class target syntax>}+
  4007         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  4008 
  4009 code_instance and code_class only are effective to target Haskell.
  4010 
  4011 For example usage see src/HOL/ex/Codegenerator.thy and
  4012 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4013 generation from Isabelle/HOL theories is available via "isatool doc
  4014 codegen".
  4015 
  4016 * Code generator: consts in 'consts_code' Isar commands are now
  4017 referred to by usual term syntax (including optional type
  4018 annotations).
  4019 
  4020 * Command 'no_translations' removes translation rules from theory
  4021 syntax.
  4022 
  4023 * Overloaded definitions are now actually checked for acyclic
  4024 dependencies.  The overloading scheme is slightly more general than
  4025 that of Haskell98, although Isabelle does not demand an exact
  4026 correspondence to type class and instance declarations.
  4027 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4028 exotic versions of overloading -- at the discretion of the user!
  4029 
  4030 Polymorphic constants are represented via type arguments, i.e. the
  4031 instantiation that matches an instance against the most general
  4032 declaration given in the signature.  For example, with the declaration
  4033 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4034 as c(nat).  Overloading is essentially simultaneous structural
  4035 recursion over such type arguments.  Incomplete specification patterns
  4036 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4037 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4038 Command 'print_theory' outputs the normalized system of recursive
  4039 equations, see section "definitions".
  4040 
  4041 * Configuration options are maintained within the theory or proof
  4042 context (with name and type bool/int/string), providing a very simple
  4043 interface to a poor-man's version of general context data.  Tools may
  4044 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4045 these values using Config.get etc.  Users may change options via an
  4046 associated attribute of the same name.  This form of context
  4047 declaration works particularly well with commands 'declare' or
  4048 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4049 very easy to avoid global references, which would not observe Isar
  4050 toplevel undo/redo and fail to work with multithreading.
  4051 
  4052 Various global ML references of Pure and HOL have been turned into
  4053 configuration options:
  4054 
  4055   Unify.search_bound		unify_search_bound
  4056   Unify.trace_bound		unify_trace_bound
  4057   Unify.trace_simp		unify_trace_simp
  4058   Unify.trace_types		unify_trace_types
  4059   Simplifier.simp_depth_limit	simp_depth_limit
  4060   Blast.depth_limit		blast_depth_limit
  4061   DatatypeProp.dtK		datatype_distinctness_limit
  4062   fast_arith_neq_limit  	fast_arith_neq_limit
  4063   fast_arith_split_limit	fast_arith_split_limit
  4064 
  4065 * Named collections of theorems may be easily installed as context
  4066 data using the functor NamedThmsFun (see also
  4067 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4068 attributes; there is also a toplevel print command.  This facility is
  4069 just a common case of general context data, which is the preferred way
  4070 for anything more complex than just a list of facts in canonical
  4071 order.
  4072 
  4073 * Isar: command 'declaration' augments a local theory by generic
  4074 declaration functions written in ML.  This enables arbitrary content
  4075 being added to the context, depending on a morphism that tells the
  4076 difference of the original declaration context wrt. the application
  4077 context encountered later on.
  4078 
  4079 * Isar: proper interfaces for simplification procedures.  Command
  4080 'simproc_setup' declares named simprocs (with match patterns, and body
  4081 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4082 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4083 
  4084 * Isar: an extra pair of brackets around attribute declarations
  4085 abbreviates a theorem reference involving an internal dummy fact,
  4086 which will be ignored later --- only the effect of the attribute on
  4087 the background context will persist.  This form of in-place
  4088 declarations is particularly useful with commands like 'declare' and
  4089 'using', for example ``have A using [[simproc a]] by simp''.
  4090 
  4091 * Isar: method "assumption" (and implicit closing of subproofs) now
  4092 takes simple non-atomic goal assumptions into account: after applying
  4093 an assumption as a rule the resulting subgoals are solved by atomic
  4094 assumption steps.  This is particularly useful to finish 'obtain'
  4095 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4096 without referring to the original premise "!!x. P x ==> thesis" in the
  4097 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4098 more permissive.
  4099 
  4100 * Isar: implicit use of prems from the Isar proof context is
  4101 considered a legacy feature.  Common applications like ``have A .''
  4102 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4103 referencing facts explicitly here improves readability and
  4104 maintainability of proof texts.
  4105 
  4106 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4107 the obtained context from the course of reasoning!  For example:
  4108 
  4109   assume "EX x y. A x & B y"   -- "any previous fact"
  4110   then guess x and y by clarify
  4111 
  4112 This technique is potentially adventurous, depending on the facts and
  4113 proof tools being involved here.
  4114 
  4115 * Isar: known facts from the proof context may be specified as literal
  4116 propositions, using ASCII back-quote syntax.  This works wherever
  4117 named facts used to be allowed so far, in proof commands, proof
  4118 methods, attributes etc.  Literal facts are retrieved from the context
  4119 according to unification of type and term parameters.  For example,
  4120 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4121 theorems in the current context, then these are valid literal facts:
  4122 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4123 
  4124 There is also a proof method "fact" which does the same composition
  4125 for explicit goal states, e.g. the following proof texts coincide with
  4126 certain special cases of literal facts:
  4127 
  4128   have "A" by fact                 ==  note `A`
  4129   have "A ==> B" by fact           ==  note `A ==> B`
  4130   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4131   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4132 
  4133 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4134 outer syntax.  Thus symbolic identifiers may be used without
  4135 additional white space in declarations like this: ``assume *: A''.
  4136 
  4137 * Isar: 'print_facts' prints all local facts of the current context,
  4138 both named and unnamed ones.
  4139 
  4140 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4141 
  4142   def x == "t" and y == "u"
  4143 
  4144 * Isar: added command 'unfolding', which is structurally similar to
  4145 'using', but affects both the goal state and facts by unfolding given
  4146 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4147 'unfolded' attribute may be replaced by first-class proof text.
  4148 
  4149 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4150 and command 'unfolding' now all support object-level equalities
  4151 (potentially conditional).  The underlying notion of rewrite rule is
  4152 analogous to the 'rule_format' attribute, but *not* that of the
  4153 Simplifier (which is usually more generous).
  4154 
  4155 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4156 premises of a theorem by n. Useful in conjunction with drule.
  4157 
  4158 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4159 method expression within a sandbox consisting of the first N
  4160 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4161 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4162 simplifies all new goals that emerge from applying rule foo to the
  4163 originally first one.
  4164 
  4165 * Isar: schematic goals are no longer restricted to higher-order
  4166 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4167 expected.
  4168 
  4169 * Isar: the conclusion of a long theorem statement is now either
  4170 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4171 (essentially a disjunction of cases with local parameters and
  4172 assumptions).  The latter allows to express general elimination rules
  4173 adequately; in this notation common elimination rules look like this:
  4174 
  4175   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4176     assumes "EX x. P x"
  4177     obtains x where "P x"
  4178 
  4179   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4180     assumes "A & B"
  4181     obtains A and B
  4182 
  4183   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4184     assumes "A | B"
  4185     obtains
  4186       A
  4187     | B
  4188 
  4189 The subsequent classical rules even refer to the formal "thesis"
  4190 explicitly:
  4191 
  4192   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4193     obtains "~ thesis"
  4194 
  4195   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4196     obtains "thesis ==> something"
  4197 
  4198 The actual proof of an 'obtains' statement is analogous to that of the
  4199 Isar proof element 'obtain', only that there may be several cases.
  4200 Optional case names may be specified in parentheses; these will be
  4201 available both in the present proof and as annotations in the
  4202 resulting rule, for later use with the 'cases' method (cf. attribute
  4203 case_names).
  4204 
  4205 * Isar: the assumptions of a long theorem statement are available as
  4206 "assms" fact in the proof context.  This is more appropriate than the
  4207 (historical) "prems", which refers to all assumptions of the current
  4208 context, including those from the target locale, proof body etc.
  4209 
  4210 * Isar: 'print_statement' prints theorems from the current theory or
  4211 proof context in long statement form, according to the syntax of a
  4212 top-level lemma.
  4213 
  4214 * Isar: 'obtain' takes an optional case name for the local context
  4215 introduction rule (default "that").
  4216 
  4217 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4218 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4219 to occur.
  4220 
  4221 * Pure: syntax "CONST name" produces a fully internalized constant
  4222 according to the current context.  This is particularly useful for
  4223 syntax translations that should refer to internal constant
  4224 representations independently of name spaces.
  4225 
  4226 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4227 instead of "FOO ". This allows multiple binder declarations to coexist
  4228 in the same context.  INCOMPATIBILITY.
  4229 
  4230 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4231 primitive that also works in a locale context (both for constants and
  4232 fixed variables). Type declaration and internal syntactic representation
  4233 of given constants retrieved from the context. Likewise, the
  4234 'no_notation' command allows to remove given syntax annotations from the
  4235 current context.
  4236 
  4237 * Isar/locales: new derived specification elements 'axiomatization',
  4238 'definition', 'abbreviation', which support type-inference, admit
  4239 object-level specifications (equality, equivalence).  See also the
  4240 isar-ref manual.  Examples:
  4241 
  4242   axiomatization
  4243     eq  (infix "===" 50) where
  4244     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4245 
  4246   definition "f x y = x + y + 1"
  4247   definition g where "g x = f x x"
  4248 
  4249   abbreviation
  4250     neq  (infix "=!=" 50) where
  4251     "x =!= y == ~ (x === y)"
  4252 
  4253 These specifications may be also used in a locale context.  Then the
  4254 constants being introduced depend on certain fixed parameters, and the
  4255 constant name is qualified by the locale base name.  An internal
  4256 abbreviation takes care for convenient input and output, making the
  4257 parameters implicit and using the original short name.  See also
  4258 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4259 entities from a monomorphic theory.
  4260 
  4261 Presently, abbreviations are only available 'in' a target locale, but
  4262 not inherited by general import expressions.  Also note that
  4263 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4264 'translations' in common applications.  The "no_abbrevs" print mode
  4265 prevents folding of abbreviations in term output.
  4266 
  4267 Concrete syntax is attached to specified constants in internal form,
  4268 independently of name spaces.  The parse tree representation is
  4269 slightly different -- use 'notation' instead of raw 'syntax', and
  4270 'translations' with explicit "CONST" markup to accommodate this.
  4271 
  4272 * Pure/Isar: unified syntax for new-style specification mechanisms
  4273 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4274 full type inference and dummy patterns ("_").  For example:
  4275 
  4276   definition "K x _ = x"
  4277 
  4278   inductive conj for A B
  4279   where "A ==> B ==> conj A B"
  4280 
  4281 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4282 the current context.  Print mode "no_abbrevs" prevents inversion of
  4283 abbreviations on output.
  4284 
  4285 * Isar/locales: improved parameter handling: use of locales "var" and
  4286 "struct" no longer necessary; - parameter renamings are no longer
  4287 required to be injective.  For example, this allows to define
  4288 endomorphisms as locale endom = homom mult mult h.
  4289 
  4290 * Isar/locales: changed the way locales with predicates are defined.
  4291 Instead of accumulating the specification, the imported expression is
  4292 now an interpretation.  INCOMPATIBILITY: different normal form of
  4293 locale expressions.  In particular, in interpretations of locales with
  4294 predicates, goals repesenting already interpreted fragments are not
  4295 removed automatically.  Use methods `intro_locales' and
  4296 `unfold_locales'; see below.
  4297 
  4298 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4299 provide backward reasoning on locales predicates.  The methods are
  4300 aware of interpretations and discharge corresponding goals.
  4301 `intro_locales' is less aggressive then `unfold_locales' and does not
  4302 unfold predicates to assumptions.
  4303 
  4304 * Isar/locales: the order in which locale fragments are accumulated
  4305 has changed.  This enables to override declarations from fragments due
  4306 to interpretations -- for example, unwanted simp rules.
  4307 
  4308 * Isar/locales: interpretation in theories and proof contexts has been
  4309 extended.  One may now specify (and prove) equations, which are
  4310 unfolded in interpreted theorems.  This is useful for replacing
  4311 defined concepts (constants depending on locale parameters) by
  4312 concepts already existing in the target context.  Example:
  4313 
  4314   interpretation partial_order ["op <= :: [int, int] => bool"]
  4315     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4316 
  4317 Typically, the constant `partial_order.less' is created by a
  4318 definition specification element in the context of locale
  4319 partial_order.
  4320 
  4321 * Method "induct": improved internal context management to support
  4322 local fixes and defines on-the-fly. Thus explicit meta-level
  4323 connectives !!  and ==> are rarely required anymore in inductive goals
  4324 (using object-logic connectives for this purpose has been long
  4325 obsolete anyway). Common proof patterns are explained in
  4326 src/HOL/Induct/Common_Patterns.thy, see also
  4327 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4328 examples.
  4329 
  4330 * Method "induct": improved handling of simultaneous goals. Instead of
  4331 introducing object-level conjunction, the statement is now split into
  4332 several conclusions, while the corresponding symbolic cases are nested
  4333 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4334 see src/HOL/Induct/Common_Patterns.thy, for example.
  4335 
  4336 * Method "induct": mutual induction rules are now specified as a list
  4337 of rule sharing the same induction cases. HOL packages usually provide
  4338 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4339 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4340 mutual induction rules differently, i.e. like this:
  4341 
  4342   (induct rule: foo_bar.inducts)
  4343   (induct set: foo bar)
  4344   (induct pred: foo bar)
  4345   (induct type: foo bar)
  4346 
  4347 The ML function ProjectRule.projections turns old-style rules into the
  4348 new format.
  4349 
  4350 * Method "coinduct": dual of induction, see
  4351 src/HOL/Library/Coinductive_List.thy for various examples.
  4352 
  4353 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4354 considered a legacy feature.
  4355 
  4356 * Attribute "symmetric" produces result with standardized schematic
  4357 variables (index 0).  Potential INCOMPATIBILITY.
  4358 
  4359 * Simplifier: by default the simplifier trace only shows top level
  4360 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4361 default. Thus there is less danger of being flooded by the trace. The
  4362 trace indicates where parts have been suppressed.
  4363   
  4364 * Provers/classical: removed obsolete classical version of elim_format
  4365 attribute; classical elim/dest rules are now treated uniformly when
  4366 manipulating the claset.
  4367 
  4368 * Provers/classical: stricter checks to ensure that supplied intro,
  4369 dest and elim rules are well-formed; dest and elim rules must have at
  4370 least one premise.
  4371 
  4372 * Provers/classical: attributes dest/elim/intro take an optional
  4373 weight argument for the rule (just as the Pure versions).  Weights are
  4374 ignored by automated tools, but determine the search order of single
  4375 rule steps.
  4376 
  4377 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4378 where the body does not mention the bound variable.  Note that dummy
  4379 patterns implicitly depend on their context of bounds, which makes
  4380 "{_. _}" match any set comprehension as expected.  Potential
  4381 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4382 constant "_idtdummy" in the binding position.
  4383 
  4384 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4385 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4386 for example "A -> B" => "Pi A (%_. B)".
  4387 
  4388 * Pure: 'class_deps' command visualizes the subclass relation, using
  4389 the graph browser tool.
  4390 
  4391 * Pure: 'print_theory' now suppresses certain internal declarations by
  4392 default; use '!' option for full details.
  4393 
  4394 
  4395 *** HOL ***
  4396 
  4397 * Method "metis" proves goals by applying the Metis general-purpose
  4398 resolution prover (see also http://gilith.com/software/metis/).
  4399 Examples are in the directory MetisExamples.  WARNING: the
  4400 Isabelle/HOL-Metis integration does not yet work properly with
  4401 multi-threading.
  4402   
  4403 * Command 'sledgehammer' invokes external automatic theorem provers as
  4404 background processes.  It generates calls to the "metis" method if
  4405 successful. These can be pasted into the proof.  Users do not have to
  4406 wait for the automatic provers to return.  WARNING: does not really
  4407 work with multi-threading.
  4408 
  4409 * New "auto_quickcheck" feature tests outermost goal statements for
  4410 potential counter-examples.  Controlled by ML references
  4411 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4412 5000 milliseconds).  Fails silently if statements is outside of
  4413 executable fragment, or any other codgenerator problem occurs.
  4414 
  4415 * New constant "undefined" with axiom "undefined x = undefined".
  4416 
  4417 * Added class "HOL.eq", allowing for code generation with polymorphic
  4418 equality.
  4419 
  4420 * Some renaming of class constants due to canonical name prefixing in
  4421 the new 'class' package:
  4422 
  4423     HOL.abs ~> HOL.abs_class.abs
  4424     HOL.divide ~> HOL.divide_class.divide
  4425     0 ~> HOL.zero_class.zero
  4426     1 ~> HOL.one_class.one
  4427     op + ~> HOL.plus_class.plus
  4428     op - ~> HOL.minus_class.minus
  4429     uminus ~> HOL.minus_class.uminus
  4430     op * ~> HOL.times_class.times
  4431     op < ~> HOL.ord_class.less
  4432     op <= > HOL.ord_class.less_eq
  4433     Nat.power ~> Power.power_class.power
  4434     Nat.size ~> Nat.size_class.size
  4435     Numeral.number_of ~> Numeral.number_class.number_of
  4436     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4437     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4438     Orderings.min ~> Orderings.ord_class.min
  4439     Orderings.max ~> Orderings.ord_class.max
  4440     Divides.op div ~> Divides.div_class.div
  4441     Divides.op mod ~> Divides.div_class.mod
  4442     Divides.op dvd ~> Divides.div_class.dvd
  4443 
  4444 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4445 
  4446 a) User-defined constants using any of the names "plus", "minus",
  4447 "times", "less" or "less_eq". The standard syntax translations for
  4448 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4449 names.
  4450 
  4451 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4452 INCOMPATIBILITY: use more specific names.
  4453 
  4454 c) Permutative equations (e.g. "a + b = b + a")
  4455 Since the change of names also changes the order of terms, permutative
  4456 rewrite rules may get applied in a different order. Experience shows
  4457 that this is rarely the case (only two adaptions in the whole Isabelle
  4458 distribution).  INCOMPATIBILITY: rewrite proofs
  4459 
  4460 d) ML code directly refering to constant names
  4461 This in general only affects hand-written proof tactics, simprocs and
  4462 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4463 Consider using @{const_name} antiquotation.
  4464 
  4465 * New class "default" with associated constant "default".
  4466 
  4467 * Function "sgn" is now overloaded and available on int, real, complex
  4468 (and other numeric types), using class "sgn".  Two possible defs of
  4469 sgn are given as equational assumptions in the classes sgn_if and
  4470 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4471 INCOMPATIBILITY.
  4472 
  4473 * Locale "partial_order" now unified with class "order" (cf. theory
  4474 Orderings), added parameter "less".  INCOMPATIBILITY.
  4475 
  4476 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4477 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4478 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4479 
  4480 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4481 changed order of proof goals in instance proofs.
  4482 
  4483 * The transitivity reasoner for partial and linear orders is set up
  4484 for classes "order" and "linorder".  Instances of the reasoner are available
  4485 in all contexts importing or interpreting the corresponding locales.
  4486 Method "order" invokes the reasoner separately; the reasoner
  4487 is also integrated with the Simplifier as a solver.  Diagnostic
  4488 command 'print_orders' shows the available instances of the reasoner
  4489 in the current context.
  4490 
  4491 * Localized monotonicity predicate in theory "Orderings"; integrated
  4492 lemmas max_of_mono and min_of_mono with this predicate.
  4493 INCOMPATIBILITY.
  4494 
  4495 * Formulation of theorem "dense" changed slightly due to integration
  4496 with new class dense_linear_order.
  4497 
  4498 * Uniform lattice theory development in HOL.
  4499 
  4500     constants "meet" and "join" now named "inf" and "sup"
  4501     constant "Meet" now named "Inf"
  4502 
  4503     classes "meet_semilorder" and "join_semilorder" now named
  4504       "lower_semilattice" and "upper_semilattice"
  4505     class "lorder" now named "lattice"
  4506     class "comp_lat" now named "complete_lattice"
  4507 
  4508     Instantiation of lattice classes allows explicit definitions
  4509     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4510 
  4511   INCOMPATIBILITY.  Theorem renames:
  4512 
  4513     meet_left_le            ~> inf_le1
  4514     meet_right_le           ~> inf_le2
  4515     join_left_le            ~> sup_ge1
  4516     join_right_le           ~> sup_ge2
  4517     meet_join_le            ~> inf_sup_ord
  4518     le_meetI                ~> le_infI
  4519     join_leI                ~> le_supI
  4520     le_meet                 ~> le_inf_iff
  4521     le_join                 ~> ge_sup_conv
  4522     meet_idempotent         ~> inf_idem
  4523     join_idempotent         ~> sup_idem
  4524     meet_comm               ~> inf_commute
  4525     join_comm               ~> sup_commute
  4526     meet_leI1               ~> le_infI1
  4527     meet_leI2               ~> le_infI2
  4528     le_joinI1               ~> le_supI1
  4529     le_joinI2               ~> le_supI2
  4530     meet_assoc              ~> inf_assoc
  4531     join_assoc              ~> sup_assoc
  4532     meet_left_comm          ~> inf_left_commute
  4533     meet_left_idempotent    ~> inf_left_idem
  4534     join_left_comm          ~> sup_left_commute
  4535     join_left_idempotent    ~> sup_left_idem
  4536     meet_aci                ~> inf_aci
  4537     join_aci                ~> sup_aci
  4538     le_def_meet             ~> le_iff_inf
  4539     le_def_join             ~> le_iff_sup
  4540     join_absorp2            ~> sup_absorb2
  4541     join_absorp1            ~> sup_absorb1
  4542     meet_absorp1            ~> inf_absorb1
  4543     meet_absorp2            ~> inf_absorb2
  4544     meet_join_absorp        ~> inf_sup_absorb
  4545     join_meet_absorp        ~> sup_inf_absorb
  4546     distrib_join_le         ~> distrib_sup_le
  4547     distrib_meet_le         ~> distrib_inf_le
  4548 
  4549     add_meet_distrib_left   ~> add_inf_distrib_left
  4550     add_join_distrib_left   ~> add_sup_distrib_left
  4551     is_join_neg_meet        ~> is_join_neg_inf
  4552     is_meet_neg_join        ~> is_meet_neg_sup
  4553     add_meet_distrib_right  ~> add_inf_distrib_right
  4554     add_join_distrib_right  ~> add_sup_distrib_right
  4555     add_meet_join_distribs  ~> add_sup_inf_distribs
  4556     join_eq_neg_meet        ~> sup_eq_neg_inf
  4557     meet_eq_neg_join        ~> inf_eq_neg_sup
  4558     add_eq_meet_join        ~> add_eq_inf_sup
  4559     meet_0_imp_0            ~> inf_0_imp_0
  4560     join_0_imp_0            ~> sup_0_imp_0
  4561     meet_0_eq_0             ~> inf_0_eq_0
  4562     join_0_eq_0             ~> sup_0_eq_0
  4563     neg_meet_eq_join        ~> neg_inf_eq_sup
  4564     neg_join_eq_meet        ~> neg_sup_eq_inf
  4565     join_eq_if              ~> sup_eq_if
  4566 
  4567     mono_meet               ~> mono_inf
  4568     mono_join               ~> mono_sup
  4569     meet_bool_eq            ~> inf_bool_eq
  4570     join_bool_eq            ~> sup_bool_eq
  4571     meet_fun_eq             ~> inf_fun_eq
  4572     join_fun_eq             ~> sup_fun_eq
  4573     meet_set_eq             ~> inf_set_eq
  4574     join_set_eq             ~> sup_set_eq
  4575     meet1_iff               ~> inf1_iff
  4576     meet2_iff               ~> inf2_iff
  4577     meet1I                  ~> inf1I
  4578     meet2I                  ~> inf2I
  4579     meet1D1                 ~> inf1D1
  4580     meet2D1                 ~> inf2D1
  4581     meet1D2                 ~> inf1D2
  4582     meet2D2                 ~> inf2D2
  4583     meet1E                  ~> inf1E
  4584     meet2E                  ~> inf2E
  4585     join1_iff               ~> sup1_iff
  4586     join2_iff               ~> sup2_iff
  4587     join1I1                 ~> sup1I1
  4588     join2I1                 ~> sup2I1
  4589     join1I1                 ~> sup1I1
  4590     join2I2                 ~> sup1I2
  4591     join1CI                 ~> sup1CI
  4592     join2CI                 ~> sup2CI
  4593     join1E                  ~> sup1E
  4594     join2E                  ~> sup2E
  4595 
  4596     is_meet_Meet            ~> is_meet_Inf
  4597     Meet_bool_def           ~> Inf_bool_def
  4598     Meet_fun_def            ~> Inf_fun_def
  4599     Meet_greatest           ~> Inf_greatest
  4600     Meet_lower              ~> Inf_lower
  4601     Meet_set_def            ~> Inf_set_def
  4602 
  4603     Sup_def                 ~> Sup_Inf
  4604     Sup_bool_eq             ~> Sup_bool_def
  4605     Sup_fun_eq              ~> Sup_fun_def
  4606     Sup_set_eq              ~> Sup_set_def
  4607 
  4608     listsp_meetI            ~> listsp_infI
  4609     listsp_meet_eq          ~> listsp_inf_eq
  4610 
  4611     meet_min                ~> inf_min
  4612     join_max                ~> sup_max
  4613 
  4614 * Added syntactic class "size"; overloaded constant "size" now has
  4615 type "'a::size ==> bool"
  4616 
  4617 * Internal reorganisation of `size' of datatypes: size theorems
  4618 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4619 simplification rules by default!); theorems "prod.size" now named
  4620 "*.size".
  4621 
  4622 * Class "div" now inherits from class "times" rather than "type".
  4623 INCOMPATIBILITY.
  4624 
  4625 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4626 Linorder etc.  have disappeared; operations defined in terms of
  4627 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4628 
  4629 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4630 
  4631 * HOL-Word: New extensive library and type for generic, fixed size
  4632 machine words, with arithemtic, bit-wise, shifting and rotating
  4633 operations, reflection into int, nat, and bool lists, automation for
  4634 linear arithmetic (by automatic reflection into nat or int), including
  4635 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4636 arithmetic type classes, supporting automatic simplification of
  4637 numerals on all operations.
  4638 
  4639 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4640 
  4641 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4642 
  4643 * Code generator library theories:
  4644   - Code_Integer represents HOL integers by big integer literals in target
  4645     languages.
  4646   - Code_Char represents HOL characters by character literals in target
  4647     languages.
  4648   - Code_Char_chr like Code_Char, but also offers treatment of character
  4649     codes; includes Code_Integer.
  4650   - Executable_Set allows to generate code for finite sets using lists.
  4651   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4652     denominator).
  4653   - Executable_Real implements a subset of real numbers, namly those
  4654     representable by rational numbers.
  4655   - Efficient_Nat implements natural numbers by integers, which in general will
  4656     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4657     includes Code_Integer.
  4658   - Code_Index provides an additional datatype index which is mapped to
  4659     target-language built-in integers.
  4660   - Code_Message provides an additional datatype message_string which is isomorphic to
  4661     strings; messages are mapped to target-language strings.
  4662 
  4663 * New package for inductive predicates
  4664 
  4665   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4666 
  4667     inductive
  4668       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4669       for z_1 :: U_1 and ... and z_n :: U_m
  4670     where
  4671       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4672     | ...
  4673 
  4674   with full support for type-inference, rather than
  4675 
  4676     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4677 
  4678     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4679     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4680 
  4681     inductive "s z_1 ... z_m"
  4682     intros
  4683       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4684       ...
  4685 
  4686   For backward compatibility, there is a wrapper allowing inductive
  4687   sets to be defined with the new package via
  4688 
  4689     inductive_set
  4690       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4691       for z_1 :: U_1 and ... and z_n :: U_m
  4692     where
  4693       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4694     | ...
  4695 
  4696   or
  4697 
  4698     inductive_set
  4699       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4700       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4701       for z_1 :: U_1 and ... and z_n :: U_m
  4702     where
  4703       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4704     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4705     | ...
  4706 
  4707   if the additional syntax "p ..." is required.
  4708 
  4709   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4710   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4711 
  4712   INCOMPATIBILITIES:
  4713 
  4714   - Since declaration and definition of inductive sets or predicates
  4715     is no longer separated, abbreviations involving the newly
  4716     introduced sets or predicates must be specified together with the
  4717     introduction rules after the 'where' keyword (see above), rather
  4718     than before the actual inductive definition.
  4719 
  4720   - The variables in induction and elimination rules are now
  4721     quantified in the order of their occurrence in the introduction
  4722     rules, rather than in alphabetical order. Since this may break
  4723     some proofs, these proofs either have to be repaired, e.g. by
  4724     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4725     statements of the form
  4726 
  4727       case (rule_i a_i_1 ... a_i_{k_i})
  4728 
  4729     or the old order of quantification has to be restored by explicitly adding
  4730     meta-level quantifiers in the introduction rules, i.e.
  4731 
  4732       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4733 
  4734   - The format of the elimination rules is now
  4735 
  4736       p z_1 ... z_m x_1 ... x_n ==>
  4737         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4738         ==> ... ==> P
  4739 
  4740     for predicates and
  4741 
  4742       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4743         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4744         ==> ... ==> P
  4745 
  4746     for sets rather than
  4747 
  4748       x : s z_1 ... z_m ==>
  4749         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4750         ==> ... ==> P
  4751 
  4752     This may require terms in goals to be expanded to n-tuples
  4753     (e.g. using case_tac or simplification with the split_paired_all
  4754     rule) before the above elimination rule is applicable.
  4755 
  4756   - The elimination or case analysis rules for (mutually) inductive
  4757     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4758     list of rules "p_1_..._p_k.elims" is no longer available.
  4759 
  4760 * New package "function"/"fun" for general recursive functions,
  4761 supporting mutual and nested recursion, definitions in local contexts,
  4762 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4763 for small examples, and the separate tutorial on the function
  4764 package. The old recdef "package" is still available as before, but
  4765 users are encouraged to use the new package.
  4766 
  4767 * Method "lexicographic_order" automatically synthesizes termination
  4768 relations as lexicographic combinations of size measures. 
  4769 
  4770 * Case-expressions allow arbitrary constructor-patterns (including
  4771 "_") and take their order into account, like in functional
  4772 programming.  Internally, this is translated into nested
  4773 case-expressions; missing cases are added and mapped to the predefined
  4774 constant "undefined". In complicated cases printing may no longer show
  4775 the original input but the internal form. Lambda-abstractions allow
  4776 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4777 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4778 variable.
  4779 
  4780 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4781 is an abbreviation for "of_nat :: nat => int". The simplification
  4782 rules for "of_nat" have been changed to work like "int" did
  4783 previously.  Potential INCOMPATIBILITY:
  4784   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4785   - of_nat_diff and of_nat_mult are no longer default simp rules
  4786 
  4787 * Method "algebra" solves polynomial equations over (semi)rings using
  4788 Groebner bases. The (semi)ring structure is defined by locales and the
  4789 tool setup depends on that generic context. Installing the method for
  4790 a specific type involves instantiating the locale and possibly adding
  4791 declarations for computation on the coefficients.  The method is
  4792 already instantiated for natural numbers and for the axiomatic class
  4793 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4794 CALCULEMUS 2007 for the general principles underlying this
  4795 architecture of context-aware proof-tools.
  4796 
  4797 * Method "ferrack" implements quantifier elimination over
  4798 special-purpose dense linear orders using locales (analogous to
  4799 "algebra"). The method is already installed for class
  4800 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4801 rat, etc.
  4802 
  4803 * Former constant "List.op @" now named "List.append".  Use ML
  4804 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4805 circumvent possible incompatibilities when working on ML level.
  4806 
  4807 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4808 
  4809 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4810 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4811 
  4812 * New syntax for Haskell-like list comprehension (input only), eg.
  4813 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4814 
  4815 * The special syntax for function "filter" has changed from [x :
  4816 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4817 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4818 
  4819 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4820 defined on nat only, as an abbreviation for [a..<Suc b]
  4821 INCOMPATIBILITY.
  4822 
  4823 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4824 
  4825 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4826 
  4827 * New lemma collection field_simps (an extension of ring_simps) for
  4828 manipulating (in)equations involving division. Multiplies with all
  4829 denominators that can be proved to be non-zero (in equations) or
  4830 positive/negative (in inequations).
  4831 
  4832 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4833 have been improved and renamed to ring_simps, group_simps and
  4834 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4835 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4836 
  4837 * Theory Library/Commutative_Ring: switched from recdef to function
  4838 package; constants add, mul, pow now curried.  Infix syntax for
  4839 algebraic operations.
  4840 
  4841 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4842 INCOMPATIBILITY.
  4843 
  4844 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4845 INCOMPATIBILITY.
  4846 
  4847 * HOL/records: generalised field-update to take a function on the
  4848 field rather than the new value: r(|A := x|) is translated to A_update
  4849 (K x) r The K-combinator that is internally used is called K_record.
  4850 INCOMPATIBILITY: Usage of the plain update functions has to be
  4851 adapted.
  4852  
  4853 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4854 * x = 0, which are required for a semiring.  Richer structures do not
  4855 inherit from semiring_0 anymore, because this property is a theorem
  4856 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4857 there is more to prove, but this is mostly trivial.
  4858 
  4859 * Class "recpower" is generalized to arbitrary monoids, not just
  4860 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4861 commutativity or semiring properties additionally.
  4862 
  4863 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4864 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4865 better use 'abbreviation'.
  4866 
  4867 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4868 
  4869 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4870 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4871 significant changes for setting up numeral syntax for types:
  4872   - New constants Numeral.pred and Numeral.succ instead
  4873       of former Numeral.bin_pred and Numeral.bin_succ.
  4874   - Use integer operations instead of bin_add, bin_mult and so on.
  4875   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4876   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4877 
  4878 See src/HOL/Integ/IntArith.thy for an example setup.
  4879 
  4880 * Command 'normal_form' computes the normal form of a term that may
  4881 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4882 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4883 heavy-duty computations because the functions are compiled to ML
  4884 first.  Correspondingly, a method "normalization" is provided.  See
  4885 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4886 
  4887 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4888 25 like -->); output depends on the "iff" print_mode, the default is
  4889 "A = B" (with priority 50).
  4890 
  4891 * Relations less (<) and less_eq (<=) are also available on type bool.
  4892 Modified syntax to disallow nesting without explicit parentheses,
  4893 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4894 INCOMPATIBILITY.
  4895 
  4896 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4897 
  4898 * Relation composition operator "op O" now has precedence 75 and binds
  4899 stronger than union and intersection. INCOMPATIBILITY.
  4900 
  4901 * The old set interval syntax "{m..n(}" (and relatives) has been
  4902 removed.  Use "{m..<n}" (and relatives) instead.
  4903 
  4904 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4905 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4906 ``declare [[simproc del: neq]]''.
  4907 
  4908 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4909 True/False.
  4910 
  4911 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4912 
  4913 * Theorem setsum_mult renamed to setsum_right_distrib.
  4914 
  4915 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4916 ``rule'' method.
  4917 
  4918 * Reimplemented methods "sat" and "satx", with several improvements:
  4919 goals no longer need to be stated as "<prems> ==> False", equivalences
  4920 (i.e. "=" on type bool) are handled, variable names of the form
  4921 "lit_<n>" are no longer reserved, significant speedup.
  4922 
  4923 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4924 zChaff is still supported as well.
  4925 
  4926 * 'inductive' and 'datatype': provide projections of mutual rules,
  4927 bundled as foo_bar.inducts;
  4928 
  4929 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4930 Library.
  4931 
  4932 * Library: moved theory Accessible_Part to main HOL.
  4933 
  4934 * Library: added theory Coinductive_List of potentially infinite lists
  4935 as greatest fixed-point.
  4936 
  4937 * Library: added theory AssocList which implements (finite) maps as
  4938 association lists.
  4939 
  4940 * Method "evaluation" solves goals (i.e. a boolean expression)
  4941 efficiently by compiling it to ML.  The goal is "proved" (via an
  4942 oracle) if it evaluates to True.
  4943 
  4944 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4945 also when invoked by the simplifier.  This results in the Simplifier
  4946 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4947 Configuration option fast_arith_split_limit=0 recovers the old
  4948 behavior.
  4949 
  4950 * Support for hex (0x20) and binary (0b1001) numerals.
  4951 
  4952 * New method: reify eqs (t), where eqs are equations for an
  4953 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4954 parameter, computes a term s::'b and a list xs::'a list and proves the
  4955 theorem I xs s = t. This is also known as reification or quoting. The
  4956 resulting theorem is applied to the subgoal to substitute t with I xs
  4957 s.  If t is omitted, the subgoal itself is reified.
  4958 
  4959 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4960 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4961 where f is supposed to be a computable function (in the sense of code
  4962 generattion). The method uses reify to compute s and xs as above then
  4963 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4964 r and finally gets the theorem t = r, which is again applied to the
  4965 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4966 
  4967 * Reflection: Automatic reification now handels binding, an example is
  4968 available in src/HOL/ex/ReflectionEx.thy
  4969 
  4970 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4971 command 'statespace' that is similar to 'record', but introduces an
  4972 abstract specification based on the locale infrastructure instead of
  4973 HOL types.  This leads to extra flexibility in composing state spaces,
  4974 in particular multiple inheritance and renaming of components.
  4975 
  4976 
  4977 *** HOL-Complex ***
  4978 
  4979 * Hyperreal: Functions root and sqrt are now defined on negative real
  4980 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4981 Nonnegativity side conditions have been removed from many lemmas, so
  4982 that more subgoals may now be solved by simplification; potential
  4983 INCOMPATIBILITY.
  4984 
  4985 * Real: new type classes formalize real normed vector spaces and
  4986 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4987 and norm :: 'a => real.
  4988 
  4989 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4990 reals into other types. The overloaded constant Reals :: 'a set is now
  4991 defined as range of_real; potential INCOMPATIBILITY.
  4992 
  4993 * Real: proper support for ML code generation, including 'quickcheck'.
  4994 Reals are implemented as arbitrary precision rationals.
  4995 
  4996 * Hyperreal: Several constants that previously worked only for the
  4997 reals have been generalized, so they now work over arbitrary vector
  4998 spaces. Type annotations may need to be added in some cases; potential
  4999 INCOMPATIBILITY.
  5000 
  5001   Infinitesimal  :: ('a::real_normed_vector) star set
  5002   HFinite        :: ('a::real_normed_vector) star set
  5003   HInfinite      :: ('a::real_normed_vector) star set
  5004   approx         :: ('a::real_normed_vector) star => 'a star => bool
  5005   monad          :: ('a::real_normed_vector) star => 'a star set
  5006   galaxy         :: ('a::real_normed_vector) star => 'a star set
  5007   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  5008   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  5009   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  5010   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  5011   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5012   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5013   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5014   sgn            :: 'a::real_normed_vector => 'a
  5015   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5016 
  5017 * Complex: Some complex-specific constants are now abbreviations for
  5018 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5019 hnorm.  Other constants have been entirely removed in favor of the
  5020 polymorphic versions (INCOMPATIBILITY):
  5021 
  5022   approx        <-- capprox
  5023   HFinite       <-- CFinite
  5024   HInfinite     <-- CInfinite
  5025   Infinitesimal <-- CInfinitesimal
  5026   monad         <-- cmonad
  5027   galaxy        <-- cgalaxy
  5028   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5029   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5030   (ns)deriv     <-- (ns)cderiv
  5031 
  5032 
  5033 *** HOL-Algebra ***
  5034 
  5035 * Formalisation of ideals and the quotient construction over rings.
  5036 
  5037 * Order and lattice theory no longer based on records.
  5038 INCOMPATIBILITY.
  5039 
  5040 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5041 greatest_closed.  INCOMPATIBILITY.
  5042 
  5043 * Method algebra is now set up via an attribute.  For examples see
  5044 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5045 of algebraic structures.
  5046 
  5047 * Renamed theory CRing to Ring.
  5048 
  5049 
  5050 *** HOL-Nominal ***
  5051 
  5052 * Substantial, yet incomplete support for nominal datatypes (binding
  5053 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5054 src/HOL/Nominal/Examples.  Prospective users should consult
  5055 http://isabelle.in.tum.de/nominal/
  5056 
  5057 
  5058 *** ML ***
  5059 
  5060 * ML basics: just one true type int, which coincides with IntInf.int
  5061 (even on SML/NJ).
  5062 
  5063 * ML within Isar: antiquotations allow to embed statically-checked
  5064 formal entities in the source, referring to the context available at
  5065 compile-time.  For example:
  5066 
  5067 ML {* @{sort "{zero,one}"} *}
  5068 ML {* @{typ "'a => 'b"} *}
  5069 ML {* @{term "%x. x"} *}
  5070 ML {* @{prop "x == y"} *}
  5071 ML {* @{ctyp "'a => 'b"} *}
  5072 ML {* @{cterm "%x. x"} *}
  5073 ML {* @{cprop "x == y"} *}
  5074 ML {* @{thm asm_rl} *}
  5075 ML {* @{thms asm_rl} *}
  5076 ML {* @{type_name c} *}
  5077 ML {* @{type_syntax c} *}
  5078 ML {* @{const_name c} *}
  5079 ML {* @{const_syntax c} *}
  5080 ML {* @{context} *}
  5081 ML {* @{theory} *}
  5082 ML {* @{theory Pure} *}
  5083 ML {* @{theory_ref} *}
  5084 ML {* @{theory_ref Pure} *}
  5085 ML {* @{simpset} *}
  5086 ML {* @{claset} *}
  5087 ML {* @{clasimpset} *}
  5088 
  5089 The same works for sources being ``used'' within an Isar context.
  5090 
  5091 * ML in Isar: improved error reporting; extra verbosity with
  5092 ML_Context.trace enabled.
  5093 
  5094 * Pure/General/table.ML: the join operations now works via exceptions
  5095 DUP/SAME instead of type option. This is simpler in simple cases, and
  5096 admits slightly more efficient complex applications.
  5097 
  5098 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5099 use Context.generic instead of just theory.
  5100 
  5101 * Pure: datatype Context.generic joins theory/Proof.context and
  5102 provides some facilities for code that works in either kind of
  5103 context, notably GenericDataFun for uniform theory and proof data.
  5104 
  5105 * Pure: simplified internal attribute type, which is now always
  5106 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5107 local (Proof.context) attributes have been discontinued, while
  5108 minimizing code duplication. Thm.rule_attribute and
  5109 Thm.declaration_attribute build canonical attributes; see also structure
  5110 Context for further operations on Context.generic, notably
  5111 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5112 declarations and definitions.
  5113 
  5114 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5115 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5116 init only required for impure data. INCOMPATIBILITY: empty really need
  5117 to be empty (no dependencies on theory content!)
  5118 
  5119 * Pure/kernel: consts certification ignores sort constraints given in
  5120 signature declarations. (This information is not relevant to the
  5121 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5122 potential INCOMPATIBILITY.
  5123 
  5124 * Pure: axiomatic type classes are now purely definitional, with
  5125 explicit proofs of class axioms and super class relations performed
  5126 internally. See Pure/axclass.ML for the main internal interfaces --
  5127 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5128 AxClass.axiomatize_class/classrel/arity supersede
  5129 Sign.add_classes/classrel/arities.
  5130 
  5131 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5132 global/local versions on theory vs. Proof.context have been
  5133 discontinued; Attrib.syntax and Method.syntax have been adapted
  5134 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5135 attributes, methods, etc.
  5136 
  5137 * Pure: several functions of signature "... -> theory -> theory * ..."
  5138 have been reoriented to "... -> theory -> ... * theory" in order to
  5139 allow natural usage in combination with the ||>, ||>>, |-> and
  5140 fold_map combinators.
  5141 
  5142 * Pure: official theorem names (closed derivations) and additional
  5143 comments (tags) are now strictly separate.  Name hints -- which are
  5144 maintained as tags -- may be attached any time without affecting the
  5145 derivation.
  5146 
  5147 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5148 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5149 achieve the old behaviour.
  5150 
  5151 * Pure: the "Goal" constant is now called "prop", supporting a
  5152 slightly more general idea of ``protecting'' meta-level rule
  5153 statements.
  5154 
  5155 * Pure: Logic.(un)varify only works in a global context, which is now
  5156 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5157 Logic.legacy_(un)varify as temporary workaround.
  5158 
  5159 * Pure: structure Name provides scalable operations for generating
  5160 internal variable names, notably Name.variants etc.  This replaces
  5161 some popular functions from term.ML:
  5162 
  5163   Term.variant		->  Name.variant
  5164   Term.variantlist	->  Name.variant_list
  5165   Term.invent_names	->  Name.invent_list
  5166 
  5167 Note that low-level renaming rarely occurs in new code -- operations
  5168 from structure Variable are used instead (see below).
  5169 
  5170 * Pure: structure Variable provides fundamental operations for proper
  5171 treatment of fixed/schematic variables in a context.  For example,
  5172 Variable.import introduces fixes for schematics of given facts and
  5173 Variable.export reverses the effect (up to renaming) -- this replaces
  5174 various freeze_thaw operations.
  5175 
  5176 * Pure: structure Goal provides simple interfaces for
  5177 init/conclude/finish and tactical prove operations (replacing former
  5178 Tactic.prove).  Goal.prove is the canonical way to prove results
  5179 within a given context; Goal.prove_global is a degraded version for
  5180 theory level goals, including a global Drule.standard.  Note that
  5181 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5182 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5183 in a locale context).
  5184 
  5185 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5186 and type checking (Syntax.check_term etc.), with common combinations
  5187 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5188 which are considered legacy and await removal.
  5189 
  5190 * Pure/Syntax: generic interfaces for type unchecking
  5191 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5192 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5193 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5194 available for convenience, but refer to the very same operations using
  5195 a mere theory instead of a full context.
  5196 
  5197 * Isar: simplified treatment of user-level errors, using exception
  5198 ERROR of string uniformly.  Function error now merely raises ERROR,
  5199 without any side effect on output channels.  The Isar toplevel takes
  5200 care of proper display of ERROR exceptions.  ML code may use plain
  5201 handle/can/try; cat_error may be used to concatenate errors like this:
  5202 
  5203   ... handle ERROR msg => cat_error msg "..."
  5204 
  5205 Toplevel ML code (run directly or through the Isar toplevel) may be
  5206 embedded into the Isar toplevel with exception display/debug like
  5207 this:
  5208 
  5209   Isar.toplevel (fn () => ...)
  5210 
  5211 INCOMPATIBILITY, removed special transform_error facilities, removed
  5212 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5213 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5214 -- use plain ERROR instead.
  5215 
  5216 * Isar: theory setup now has type (theory -> theory), instead of a
  5217 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5218 
  5219 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5220 ProofContext.debug/verbose flags.
  5221 
  5222 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5223 theory before entering a proof state.  Transactions now always see a
  5224 quasi-functional intermediate checkpoint, both in interactive and
  5225 batch mode.
  5226 
  5227 * Isar: simplified interfaces for outer syntax.  Renamed
  5228 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5229 OuterSyntax.add_parsers -- this functionality is now included in
  5230 OuterSyntax.command etc.  INCOMPATIBILITY.
  5231 
  5232 * Simplifier: the simpset of a running simplification process now
  5233 contains a proof context (cf. Simplifier.the_context), which is the
  5234 very context that the initial simpset has been retrieved from (by
  5235 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5236 (solver, looper etc.) may depend on arbitrary proof data.
  5237 
  5238 * Simplifier.inherit_context inherits the proof context (plus the
  5239 local bounds) of the current simplification process; any simproc
  5240 etc. that calls the Simplifier recursively should do this!  Removed
  5241 former Simplifier.inherit_bounds, which is already included here --
  5242 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5243 specify an explicit context using Simplifier.context/theory_context.
  5244 
  5245 * Simplifier/Classical Reasoner: more abstract interfaces
  5246 change_simpset/claset for modifying the simpset/claset reference of a
  5247 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5248 INCOMPATIBILITY.
  5249 
  5250 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5251 "Trueprop" etc.
  5252 
  5253 
  5254 *** System ***
  5255 
  5256 * settings: the default heap location within ISABELLE_HOME_USER now
  5257 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5258 Isabelle installations.
  5259 
  5260 * isabelle-process: option -S (secure mode) disables some critical
  5261 operations, notably runtime compilation and evaluation of ML source
  5262 code.
  5263 
  5264 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5265 
  5266 * Support for parallel execution, using native multicore support of
  5267 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5268 independent theories, according to the given theory header
  5269 specifications. The maximum number of worker threads is specified via
  5270 usedir option -M or the "max-threads" setting in Proof General. A
  5271 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5272 to 6 on a 8-core machine.  User-code needs to observe certain
  5273 guidelines for thread-safe programming, see appendix A in the Isar
  5274 Implementation manual.
  5275 
  5276 
  5277 
  5278 New in Isabelle2005 (October 2005)
  5279 ----------------------------------
  5280 
  5281 *** General ***
  5282 
  5283 * Theory headers: the new header syntax for Isar theories is
  5284 
  5285   theory <name>
  5286   imports <theory1> ... <theoryN>
  5287   uses <file1> ... <fileM>
  5288   begin
  5289 
  5290 where the 'uses' part is optional.  The previous syntax
  5291 
  5292   theory <name> = <theory1> + ... + <theoryN>:
  5293 
  5294 will disappear in the next release.  Use isatool fixheaders to convert
  5295 existing theory files.  Note that there is no change in ancient
  5296 non-Isar theories now, but these will disappear soon.
  5297 
  5298 * Theory loader: parent theories can now also be referred to via
  5299 relative and absolute paths.
  5300 
  5301 * Command 'find_theorems' searches for a list of criteria instead of a
  5302 list of constants. Known criteria are: intro, elim, dest, name:string,
  5303 simp:term, and any term. Criteria can be preceded by '-' to select
  5304 theorems that do not match. Intro, elim, dest select theorems that
  5305 match the current goal, name:s selects theorems whose fully qualified
  5306 name contain s, and simp:term selects all simplification rules whose
  5307 lhs match term.  Any other term is interpreted as pattern and selects
  5308 all theorems matching the pattern. Available in ProofGeneral under
  5309 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5310 
  5311   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5312 
  5313 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5314 matching the current goal as introduction rule and not having "HOL."
  5315 in their name (i.e. not being defined in theory HOL).
  5316 
  5317 * Command 'thms_containing' has been discontinued in favour of
  5318 'find_theorems'; INCOMPATIBILITY.
  5319 
  5320 * Communication with Proof General is now 8bit clean, which means that
  5321 Unicode text in UTF-8 encoding may be used within theory texts (both
  5322 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5323 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5324 
  5325   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5326   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5327 
  5328 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5329 Classical Reasoner.  Typical big applications run around 2 times
  5330 faster.
  5331 
  5332 
  5333 *** Document preparation ***
  5334 
  5335 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5336 of raw sources.  Only those symbols that do not require additional
  5337 LaTeX packages (depending on comments in isabellesym.sty) are
  5338 displayed properly, everything else is left verbatim.  isatool display
  5339 and isatool print are used as front ends (these are subject to the
  5340 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5341 
  5342 * Command tags control specific markup of certain regions of text,
  5343 notably folding and hiding.  Predefined tags include "theory" (for
  5344 theory begin and end), "proof" for proof commands, and "ML" for
  5345 commands involving ML code; the additional tags "visible" and
  5346 "invisible" are unused by default.  Users may give explicit tag
  5347 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5348 interpretation of tags is determined by the LaTeX job during document
  5349 preparation: see option -V of isatool usedir, or options -n and -t of
  5350 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5351 \isadroptag.
  5352 
  5353 Several document versions may be produced at the same time via isatool
  5354 usedir (the generated index.html will link all of them).  Typical
  5355 specifications include ''-V document=theory,proof,ML'' to present
  5356 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5357 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5358 these parts without any formal replacement text.  The Isabelle site
  5359 default settings produce ''document'' and ''outline'' versions as
  5360 specified above.
  5361 
  5362 * Several new antiquotations:
  5363 
  5364   @{term_type term} prints a term with its type annotated;
  5365 
  5366   @{typeof term} prints the type of a term;
  5367 
  5368   @{const const} is the same as @{term const}, but checks that the
  5369   argument is a known logical constant;
  5370 
  5371   @{term_style style term} and @{thm_style style thm} print a term or
  5372   theorem applying a "style" to it
  5373 
  5374   @{ML text}
  5375 
  5376 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5377 definitions, equations, inequations etc., 'concl' printing only the
  5378 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5379 to print the specified premise.  TermStyle.add_style provides an ML
  5380 interface for introducing further styles.  See also the "LaTeX Sugar"
  5381 document practical applications.  The ML antiquotation prints
  5382 type-checked ML expressions verbatim.
  5383 
  5384 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5385 and 'text' support optional locale specification '(in loc)', which
  5386 specifies the default context for interpreting antiquotations.  For
  5387 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5388 
  5389 * Option 'locale=NAME' of antiquotations specifies an alternative
  5390 context interpreting the subsequent argument.  For example: @{thm
  5391 [locale=lattice] inf_assoc}.
  5392 
  5393 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5394 a proof context.
  5395 
  5396 * Proper output of antiquotations for theory commands involving a
  5397 proof context (such as 'locale' or 'theorem (in loc) ...').
  5398 
  5399 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5400 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5401 
  5402 * isatool usedir: new option -C (default true) controls whether option
  5403 -D should include a copy of the original document directory; -C false
  5404 prevents unwanted effects such as copying of administrative CVS data.
  5405 
  5406 
  5407 *** Pure ***
  5408 
  5409 * Considerably improved version of 'constdefs' command.  Now performs
  5410 automatic type-inference of declared constants; additional support for
  5411 local structure declarations (cf. locales and HOL records), see also
  5412 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5413 sequential dependencies of definitions within a single 'constdefs'
  5414 section; moreover, the declared name needs to be an identifier.  If
  5415 all fails, consider to fall back on 'consts' and 'defs' separately.
  5416 
  5417 * Improved indexed syntax and implicit structures.  First of all,
  5418 indexed syntax provides a notational device for subscripted
  5419 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5420 expressions.  Secondly, in a local context with structure
  5421 declarations, number indexes \<^sub>n or the empty index (default
  5422 number 1) refer to a certain fixed variable implicitly; option
  5423 show_structs controls printing of implicit structures.  Typical
  5424 applications of these concepts involve record types and locales.
  5425 
  5426 * New command 'no_syntax' removes grammar declarations (and
  5427 translations) resulting from the given syntax specification, which is
  5428 interpreted in the same manner as for the 'syntax' command.
  5429 
  5430 * 'Advanced' translation functions (parse_translation etc.) may depend
  5431 on the signature of the theory context being presently used for
  5432 parsing/printing, see also isar-ref manual.
  5433 
  5434 * Improved 'oracle' command provides a type-safe interface to turn an
  5435 ML expression of type theory -> T -> term into a primitive rule of
  5436 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5437 is already included here); see also FOL/ex/IffExample.thy;
  5438 INCOMPATIBILITY.
  5439 
  5440 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5441 before); "cI" is no longer bound, use "c.intro" instead.
  5442 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5443 axclasses vs. locales.
  5444 
  5445 * Improved internal renaming of symbolic identifiers -- attach primes
  5446 instead of base 26 numbers.
  5447 
  5448 * New flag show_question_marks controls printing of leading question
  5449 marks in schematic variable names.
  5450 
  5451 * In schematic variable names, *any* symbol following \<^isub> or
  5452 \<^isup> is now treated as part of the base name.  For example, the
  5453 following works without printing of awkward ".0" indexes:
  5454 
  5455   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5456     by simp
  5457 
  5458 * Inner syntax includes (*(*nested*) comments*).
  5459 
  5460 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5461 annotations as "(00...)".
  5462 
  5463 * Clear separation of logical types and nonterminals, where the latter
  5464 may only occur in 'syntax' specifications or type abbreviations.
  5465 Before that distinction was only partially implemented via type class
  5466 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5467 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5468 exotic syntax specifications may require further adaption
  5469 (e.g. Cube/Cube.thy).
  5470 
  5471 * Removed obsolete type class "logic", use the top sort {} instead.
  5472 Note that non-logical types should be declared as 'nonterminals'
  5473 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5474 specifications.
  5475 
  5476 * Attributes 'induct' and 'cases': type or set names may now be
  5477 locally fixed variables as well.
  5478 
  5479 * Simplifier: can now control the depth to which conditional rewriting
  5480 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5481 Limit.
  5482 
  5483 * Simplifier: simplification procedures may now take the current
  5484 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5485 interface), which is very useful for calling the Simplifier
  5486 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5487 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5488 low-level mk_simproc no longer applies Logic.varify internally, to
  5489 allow for use in a context of fixed variables.
  5490 
  5491 * thin_tac now works even if the assumption being deleted contains !!
  5492 or ==>.  More generally, erule now works even if the major premise of
  5493 the elimination rule contains !! or ==>.
  5494 
  5495 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5496 
  5497 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5498 from Pure, which contains all common declarations already.  Both
  5499 theories are defined via plain Isabelle/Isar .thy files.
  5500 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5501 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5502 use isatool fixcpure to adapt your theory and ML sources.
  5503 
  5504 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5505 selections of theorems in named facts via index ranges.
  5506 
  5507 * 'print_theorems': in theory mode, really print the difference
  5508 wrt. the last state (works for interactive theory development only),
  5509 in proof mode print all local facts (cf. 'print_facts');
  5510 
  5511 * 'hide': option '(open)' hides only base names.
  5512 
  5513 * More efficient treatment of intermediate checkpoints in interactive
  5514 theory development.
  5515 
  5516 * Code generator is now invoked via code_module (incremental code
  5517 generation) and code_library (modular code generation, ML structures
  5518 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5519 must be quoted when used as identifiers.
  5520 
  5521 * New 'value' command for reading, evaluating and printing terms using
  5522 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5523 quoted when used as identifier.
  5524 
  5525 
  5526 *** Locales ***
  5527 
  5528 * New commands for the interpretation of locale expressions in
  5529 theories (1), locales (2) and proof contexts (3).  These generate
  5530 proof obligations from the expression specification.  After the
  5531 obligations have been discharged, theorems of the expression are added
  5532 to the theory, target locale or proof context.  The synopsis of the
  5533 commands is a follows:
  5534 
  5535   (1) interpretation expr inst
  5536   (2) interpretation target < expr
  5537   (3) interpret expr inst
  5538 
  5539 Interpretation in theories and proof contexts require a parameter
  5540 instantiation of terms from the current context.  This is applied to
  5541 specifications and theorems of the interpreted expression.
  5542 Interpretation in locales only permits parameter renaming through the
  5543 locale expression.  Interpretation is smart in that interpretations
  5544 that are active already do not occur in proof obligations, neither are
  5545 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5546 inspect active interpretations of a particular locale.  For details,
  5547 see the Isar Reference manual.  Examples can be found in
  5548 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5549 
  5550 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5551 'interpret' instead.
  5552 
  5553 * New context element 'constrains' for adding type constraints to
  5554 parameters.
  5555 
  5556 * Context expressions: renaming of parameters with syntax
  5557 redeclaration.
  5558 
  5559 * Locale declaration: 'includes' disallowed.
  5560 
  5561 * Proper static binding of attribute syntax -- i.e. types / terms /
  5562 facts mentioned as arguments are always those of the locale definition
  5563 context, independently of the context of later invocations.  Moreover,
  5564 locale operations (renaming and type / term instantiation) are applied
  5565 to attribute arguments as expected.
  5566 
  5567 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5568 actual attributes; rare situations may require Attrib.attribute to
  5569 embed those attributes into Attrib.src that lack concrete syntax.
  5570 Attribute implementations need to cooperate properly with the static
  5571 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5572 Attrib.XXX_thm etc. already do the right thing without further
  5573 intervention.  Only unusual applications -- such as "where" or "of"
  5574 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5575 on the context and the facts involved -- may have to assign parsed
  5576 values to argument tokens explicitly.
  5577 
  5578 * Changed parameter management in theorem generation for long goal
  5579 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5580 theorem statement in rare situations.
  5581 
  5582 * Locale inspection command 'print_locale' omits notes elements.  Use
  5583 'print_locale!' to have them included in the output.
  5584 
  5585 
  5586 *** Provers ***
  5587 
  5588 * Provers/hypsubst.ML: improved version of the subst method, for
  5589 single-step rewriting: it now works in bound variable contexts. New is
  5590 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5591 rewrite a different subterm than the original subst method, which is
  5592 still available as 'simplesubst'.
  5593 
  5594 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5595 and quasi orders.
  5596 
  5597 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5598 reflexive-transitive closure of relations.
  5599 
  5600 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5601 limit (previously hard-coded with a value of 20) user-definable.
  5602 
  5603 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5604 is peformed already.  Object-logics merely need to finish their
  5605 initial simpset configuration as before.  INCOMPATIBILITY.
  5606 
  5607 
  5608 *** HOL ***
  5609 
  5610 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5611 
  5612   syntax (epsilon)
  5613     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5614 
  5615 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5616 and x-symbol; use option '-m epsilon' to get it actually printed.
  5617 Moreover, the mathematically important symbolic identifier \<epsilon>
  5618 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5619 
  5620 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5621 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5622 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5623 support corresponding Isar calculations.
  5624 
  5625 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5626 instead of ":".
  5627 
  5628 * theory SetInterval: changed the syntax for open intervals:
  5629 
  5630   Old       New
  5631   {..n(}    {..<n}
  5632   {)n..}    {n<..}
  5633   {m..n(}   {m..<n}
  5634   {)m..n}   {m<..n}
  5635   {)m..n(}  {m<..<n}
  5636 
  5637 The old syntax is still supported but will disappear in the next
  5638 release.  For conversion use the following Emacs search and replace
  5639 patterns (these are not perfect but work quite well):
  5640 
  5641   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5642   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5643 
  5644 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5645 equalities in commutative rings; method 'algebra' provides a generic
  5646 interface.
  5647 
  5648 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5649 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5650 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5651 be a tuple pattern.
  5652 
  5653 Some new syntax forms are available:
  5654 
  5655   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5656   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5657   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5658   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5659 
  5660 The latter form "\<Sum>x < k. e" used to be based on a separate
  5661 function "Summation", which has been discontinued.
  5662 
  5663 * theory Finite_Set: in structured induction proofs, the insert case
  5664 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5665 (insert F x)'.
  5666 
  5667 * The 'refute' command has been extended to support a much larger
  5668 fragment of HOL, including axiomatic type classes, constdefs and
  5669 typedefs, inductive datatypes and recursion.
  5670 
  5671 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5672 Requires zChaff with proof generation to be installed.  See
  5673 HOL/ex/SAT_Examples.thy for examples.
  5674 
  5675 * Datatype induction via method 'induct' now preserves the name of the
  5676 induction variable. For example, when proving P(xs::'a list) by
  5677 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5678 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5679 in unstructured proof scripts.
  5680 
  5681 * Reworked implementation of records.  Improved scalability for
  5682 records with many fields, avoiding performance problems for type
  5683 inference. Records are no longer composed of nested field types, but
  5684 of nested extension types. Therefore the record type only grows linear
  5685 in the number of extensions and not in the number of fields.  The
  5686 top-level (users) view on records is preserved.  Potential
  5687 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5688 old record representation. The type generated for a record is called
  5689 <record_name>_ext_type.
  5690 
  5691 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5692 proofs triggered by a record definition or a simproc (if
  5693 quick_and_dirty is enabled).  Definitions of large records can take
  5694 quite long.
  5695 
  5696 New simproc record_upd_simproc for simplification of multiple record
  5697 updates enabled by default.  Moreover, trivial updates are also
  5698 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5699 occasionally, since simplification is more powerful by default.
  5700 
  5701 * typedef: proper support for polymorphic sets, which contain extra
  5702 type-variables in the term.
  5703 
  5704 * Simplifier: automatically reasons about transitivity chains
  5705 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5706 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5707 old proofs break occasionally as simplification may now solve more
  5708 goals than previously.
  5709 
  5710 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5711 present.  Works for all partial orders (class "order"), in particular
  5712 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5713 just like y <= x.
  5714 
  5715 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5716 bound variable or a constant then the let is unfolded.  Otherwise
  5717 first a is simplified to b, and then f b is simplified to g. If
  5718 possible we abstract b from g arriving at "let x = b in h x",
  5719 otherwise we unfold the let and arrive at g.  The simproc can be
  5720 enabled/disabled by the reference use_let_simproc.  Potential
  5721 INCOMPATIBILITY since simplification is more powerful by default.
  5722 
  5723 * Classical reasoning: the meson method now accepts theorems as arguments.
  5724 
  5725 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5726 jobs to provide advice on the provability of subgoals.
  5727 
  5728 * Theory OrderedGroup and Ring_and_Field: various additions and
  5729 improvements to faciliate calculations involving equalities and
  5730 inequalities.
  5731 
  5732 The following theorems have been eliminated or modified
  5733 (INCOMPATIBILITY):
  5734 
  5735   abs_eq             now named abs_of_nonneg
  5736   abs_of_ge_0        now named abs_of_nonneg
  5737   abs_minus_eq       now named abs_of_nonpos
  5738   imp_abs_id         now named abs_of_nonneg
  5739   imp_abs_neg_id     now named abs_of_nonpos
  5740   mult_pos           now named mult_pos_pos
  5741   mult_pos_le        now named mult_nonneg_nonneg
  5742   mult_pos_neg_le    now named mult_nonneg_nonpos
  5743   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5744   mult_neg           now named mult_neg_neg
  5745   mult_neg_le        now named mult_nonpos_nonpos
  5746 
  5747 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5748      
  5749      zero_le_square
  5750      not_square_less_zero 
  5751 
  5752   The following lemmas have been deleted from Real/RealPow:
  5753   
  5754      realpow_zero_zero
  5755      realpow_two
  5756      realpow_less
  5757      zero_le_power
  5758      realpow_two_le
  5759      abs_realpow_two
  5760      realpow_two_abs     
  5761 
  5762 * Theory Parity: added rules for simplifying exponents.
  5763 
  5764 * Theory List:
  5765 
  5766 The following theorems have been eliminated or modified
  5767 (INCOMPATIBILITY):
  5768 
  5769   list_all_Nil       now named list_all.simps(1)
  5770   list_all_Cons      now named list_all.simps(2)
  5771   list_all_conv      now named list_all_iff
  5772   set_mem_eq         now named mem_iff
  5773 
  5774 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5775 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5776 
  5777 
  5778 *** HOL-Complex ***
  5779 
  5780 * Theory RealDef: better support for embedding natural numbers and
  5781 integers in the reals.
  5782 
  5783 The following theorems have been eliminated or modified
  5784 (INCOMPATIBILITY):
  5785 
  5786   exp_ge_add_one_self  now requires no hypotheses
  5787   real_of_int_add      reversed direction of equality (use [symmetric])
  5788   real_of_int_minus    reversed direction of equality (use [symmetric])
  5789   real_of_int_diff     reversed direction of equality (use [symmetric])
  5790   real_of_int_mult     reversed direction of equality (use [symmetric])
  5791 
  5792 * Theory RComplete: expanded support for floor and ceiling functions.
  5793 
  5794 * Theory Ln is new, with properties of the natural logarithm
  5795 
  5796 * Hyperreal: There is a new type constructor "star" for making
  5797 nonstandard types.  The old type names are now type synonyms:
  5798 
  5799   hypreal = real star
  5800   hypnat = nat star
  5801   hcomplex = complex star
  5802 
  5803 * Hyperreal: Many groups of similarly-defined constants have been
  5804 replaced by polymorphic versions (INCOMPATIBILITY):
  5805 
  5806   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5807 
  5808   starset      <-- starsetNat, starsetC
  5809   *s*          <-- *sNat*, *sc*
  5810   starset_n    <-- starsetNat_n, starsetC_n
  5811   *sn*         <-- *sNatn*, *scn*
  5812   InternalSets <-- InternalNatSets, InternalCSets
  5813 
  5814   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5815   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5816   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5817   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5818   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5819 
  5820 * Hyperreal: Many type-specific theorems have been removed in favor of
  5821 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5822 
  5823   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5824   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5825   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5826   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5827   right_minus <-- hypreal_add_minus
  5828   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5829   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5830   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5831   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5832   mult_1_right <-- hcomplex_mult_one_right
  5833   mult_zero_left <-- hcomplex_mult_zero_left
  5834   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5835   right_distrib <-- hypnat_add_mult_distrib2
  5836   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5837   right_inverse <-- hypreal_mult_inverse
  5838   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5839   order_refl <-- {hypreal,hypnat}_le_refl
  5840   order_trans <-- {hypreal,hypnat}_le_trans
  5841   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5842   order_less_le <-- {hypreal,hypnat}_less_le
  5843   linorder_linear <-- {hypreal,hypnat}_le_linear
  5844   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5845   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5846   add_nonneg_nonneg <-- hypreal_le_add_order
  5847 
  5848 * Hyperreal: Separate theorems having to do with type-specific
  5849 versions of constants have been merged into theorems that apply to the
  5850 new polymorphic constants (INCOMPATIBILITY):
  5851 
  5852   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5853   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5854   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5855   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5856   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5857   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5858   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5859   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5860   STAR_diff <-- {STAR,STARC}_diff
  5861   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5862     STARC_hcomplex_of_complex}_image_subset
  5863   starset_n_Un <-- starset{Nat,C}_n_Un
  5864   starset_n_Int <-- starset{Nat,C}_n_Int
  5865   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5866   starset_n_diff <-- starset{Nat,C}_n_diff
  5867   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5868   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5869   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5870   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5871   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5872   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5873   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5874   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5875   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5876   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5877   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5878   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5879   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5880   starfun_diff <-- starfun{C,RC,CR}_diff
  5881   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5882   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5883   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5884   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5885   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5886   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5887   starfun_Id <-- starfunC_Id
  5888   starfun_approx <-- starfun{Nat,CR}_approx
  5889   starfun_capprox <-- starfun{C,RC}_capprox
  5890   starfun_abs <-- starfunNat_rabs
  5891   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5892   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5893   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5894   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5895   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5896   starfun_add_approx <-- starfunCR_add_approx
  5897   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5898   starfun_divide <-- starfun{C,CR,RC}_divide
  5899   starfun_n <-- starfun{Nat,C}_n
  5900   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5901   starfun_n_add <-- starfun{Nat,C}_n_add
  5902   starfun_n_add_minus <-- starfunNat_n_add_minus
  5903   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5904   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5905   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5906 
  5907   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5908   star_n_minus <-- {hypreal,hcomplex}_minus
  5909   star_n_diff <-- {hypreal,hcomplex}_diff
  5910   star_n_mult <-- {hypreal,hcomplex}_mult
  5911   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5912   star_n_le <-- {hypreal,hypnat}_le
  5913   star_n_less <-- {hypreal,hypnat}_less
  5914   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5915   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5916   star_n_abs <-- hypreal_hrabs
  5917   star_n_divide <-- hcomplex_divide
  5918 
  5919   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5920   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5921   star_of_diff <-- hypreal_of_real_diff
  5922   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5923   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5924   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5925   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5926   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5927   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5928   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5929   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5930   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5931   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5932   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5933   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5934   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5935   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5936   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5937   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5938   star_of_power <-- hypreal_of_real_power
  5939   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5940 
  5941 * Hyperreal: new method "transfer" that implements the transfer
  5942 principle of nonstandard analysis. With a subgoal that mentions
  5943 nonstandard types like "'a star", the command "apply transfer"
  5944 replaces it with an equivalent one that mentions only standard types.
  5945 To be successful, all free variables must have standard types; non-
  5946 standard variables must have explicit universal quantifiers.
  5947 
  5948 * Hyperreal: A theory of Taylor series.
  5949 
  5950 
  5951 *** HOLCF ***
  5952 
  5953 * Discontinued special version of 'constdefs' (which used to support
  5954 continuous functions) in favor of the general Pure one with full
  5955 type-inference.
  5956 
  5957 * New simplification procedure for solving continuity conditions; it
  5958 is much faster on terms with many nested lambda abstractions (cubic
  5959 instead of exponential time).
  5960 
  5961 * New syntax for domain package: selector names are now optional.
  5962 Parentheses should be omitted unless argument is lazy, for example:
  5963 
  5964   domain 'a stream = cons "'a" (lazy "'a stream")
  5965 
  5966 * New command 'fixrec' for defining recursive functions with pattern
  5967 matching; defining multiple functions with mutual recursion is also
  5968 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5969 sinr, or any data constructor defined by the domain package. The given
  5970 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5971 syntax and examples.
  5972 
  5973 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5974 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5975 but the proof obligation additionally includes an admissibility
  5976 requirement. The packages generate instances of class cpo or pcpo,
  5977 with continuity and strictness theorems for Rep and Abs.
  5978 
  5979 * HOLCF: Many theorems have been renamed according to a more standard naming
  5980 scheme (INCOMPATIBILITY):
  5981 
  5982   foo_inject:  "foo$x = foo$y ==> x = y"
  5983   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5984   foo_less:    "(foo$x << foo$y) = (x << y)"
  5985   foo_strict:  "foo$UU = UU"
  5986   foo_defined: "... ==> foo$x ~= UU"
  5987   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5988 
  5989 
  5990 *** ZF ***
  5991 
  5992 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5993 including the First Isomorphism Theorem (on quotienting by the kernel
  5994 of a homomorphism).
  5995 
  5996 * ZF/Simplifier: install second copy of type solver that actually
  5997 makes use of TC rules declared to Isar proof contexts (or locales);
  5998 the old version is still required for ML proof scripts.
  5999 
  6000 
  6001 *** Cube ***
  6002 
  6003 * Converted to Isar theory format; use locales instead of axiomatic
  6004 theories.
  6005 
  6006 
  6007 *** ML ***
  6008 
  6009 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  6010 for ||>, ||>>, |>>,
  6011 
  6012 * Pure/library.ML no longer defines its own option datatype, but uses
  6013 that of the SML basis, which has constructors NONE and SOME instead of
  6014 None and Some, as well as exception Option.Option instead of OPTION.
  6015 The functions the, if_none, is_some, is_none have been adapted
  6016 accordingly, while Option.map replaces apsome.
  6017 
  6018 * Pure/library.ML: the exception LIST has been given up in favour of
  6019 the standard exceptions Empty and Subscript, as well as
  6020 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6021 superceded by the standard hd and tl functions etc.
  6022 
  6023 A number of basic list functions are no longer exported to the ML
  6024 toplevel, as they are variants of predefined functions.  The following
  6025 suggests how one can translate existing code:
  6026 
  6027     rev_append xs ys = List.revAppend (xs, ys)
  6028     nth_elem (i, xs) = List.nth (xs, i)
  6029     last_elem xs = List.last xs
  6030     flat xss = List.concat xss
  6031     seq fs = List.app fs
  6032     partition P xs = List.partition P xs
  6033     mapfilter f xs = List.mapPartial f xs
  6034 
  6035 * Pure/library.ML: several combinators for linear functional
  6036 transformations, notably reverse application and composition:
  6037 
  6038   x |> f                f #> g
  6039   (x, y) |-> f          f #-> g
  6040 
  6041 * Pure/library.ML: introduced/changed precedence of infix operators:
  6042 
  6043   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6044   infix 2 ?;
  6045   infix 3 o oo ooo oooo;
  6046   infix 4 ~~ upto downto;
  6047 
  6048 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6049 infix operators.
  6050 
  6051 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6052 fold_map support linear functional transformations and nesting.  For
  6053 example:
  6054 
  6055   fold f [x1, ..., xN] y =
  6056     y |> f x1 |> ... |> f xN
  6057 
  6058   (fold o fold) f [xs1, ..., xsN] y =
  6059     y |> fold f xs1 |> ... |> fold f xsN
  6060 
  6061   fold f [x1, ..., xN] =
  6062     f x1 #> ... #> f xN
  6063 
  6064   (fold o fold) f [xs1, ..., xsN] =
  6065     fold f xs1 #> ... #> fold f xsN
  6066 
  6067 * Pure/library.ML: the following selectors on type 'a option are
  6068 available:
  6069 
  6070   the:               'a option -> 'a  (*partial*)
  6071   these:             'a option -> 'a  where 'a = 'b list
  6072   the_default: 'a -> 'a option -> 'a
  6073   the_list:          'a option -> 'a list
  6074 
  6075 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6076 basic operations for association lists, following natural argument
  6077 order; moreover the explicit equality predicate passed here avoids
  6078 potentially expensive polymorphic runtime equality checks.
  6079 The old functions may be expressed as follows:
  6080 
  6081   assoc = uncurry (AList.lookup (op =))
  6082   assocs = these oo AList.lookup (op =)
  6083   overwrite = uncurry (AList.update (op =)) o swap
  6084 
  6085 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6086 
  6087   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6088   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6089 
  6090 replacing make_keylist and keyfilter (occassionally used)
  6091 Naive rewrites:
  6092 
  6093   make_keylist = AList.make
  6094   keyfilter = AList.find (op =)
  6095 
  6096 * eq_fst and eq_snd now take explicit equality parameter, thus
  6097   avoiding eqtypes. Naive rewrites:
  6098 
  6099     eq_fst = eq_fst (op =)
  6100     eq_snd = eq_snd (op =)
  6101 
  6102 * Removed deprecated apl and apr (rarely used).
  6103   Naive rewrites:
  6104 
  6105     apl (n, op) =>>= curry op n
  6106     apr (op, m) =>>= fn n => op (n, m)
  6107 
  6108 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6109 provides a reasonably efficient light-weight implementation of sets as
  6110 lists.
  6111 
  6112 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6113 few new operations; existing lookup and update are now curried to
  6114 follow natural argument order (for use with fold etc.);
  6115 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6116 
  6117 * Pure/General: output via the Isabelle channels of
  6118 writeln/warning/error etc. is now passed through Output.output, with a
  6119 hook for arbitrary transformations depending on the print_mode
  6120 (cf. Output.add_mode -- the first active mode that provides a output
  6121 function wins).  Already formatted output may be embedded into further
  6122 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6123 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6124 accommodate easy composition of diagnostic messages etc.  Programmers
  6125 rarely need to care about Output.output or Output.raw at all, with
  6126 some notable exceptions: Output.output is required when bypassing the
  6127 standard channels (writeln etc.), or in token translations to produce
  6128 properly formatted results; Output.raw is required when capturing
  6129 already output material that will eventually be presented to the user
  6130 a second time.  For the default print mode, both Output.output and
  6131 Output.raw have no effect.
  6132 
  6133 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6134 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6135 cumulative results are displayed at the end of a batch session.
  6136 
  6137 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6138 replaced by File.platform_path and File.shell_path (with appropriate
  6139 hooks).  This provides a clean interface for unusual systems where the
  6140 internal and external process view of file names are different.
  6141 
  6142 * Pure: more efficient orders for basic syntactic entities: added
  6143 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6144 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6145 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6146 orders now -- potential INCOMPATIBILITY for code that depends on a
  6147 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6148 Library.sort_strings on result).
  6149 
  6150 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6151 fold_types traverse types/terms from left to right, observing natural
  6152 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6153 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6154 
  6155 * Pure: name spaces have been refined, with significant changes of the
  6156 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6157 to extern(_table).  The plain name entry path is superceded by a
  6158 general 'naming' context, which also includes the 'policy' to produce
  6159 a fully qualified name and external accesses of a fully qualified
  6160 name; NameSpace.extend is superceded by context dependent
  6161 Sign.declare_name.  Several theory and proof context operations modify
  6162 the naming context.  Especially note Theory.restore_naming and
  6163 ProofContext.restore_naming to get back to a sane state; note that
  6164 Theory.add_path is no longer sufficient to recover from
  6165 Theory.absolute_path in particular.
  6166 
  6167 * Pure: new flags short_names (default false) and unique_names
  6168 (default true) for controlling output of qualified names.  If
  6169 short_names is set, names are printed unqualified.  If unique_names is
  6170 reset, the name prefix is reduced to the minimum required to achieve
  6171 the original result when interning again, even if there is an overlap
  6172 with earlier declarations.
  6173 
  6174 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6175 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6176 (useful for printing error messages).  INCOMPATIBILITY.
  6177 
  6178 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6179 Theory.theory are now identified, referring to the universal
  6180 Context.theory (see Pure/context.ML).  Actual signature and theory
  6181 content is managed as theory data.  The old code and interfaces were
  6182 spread over many files and structures; the new arrangement introduces
  6183 considerable INCOMPATIBILITY to gain more clarity:
  6184 
  6185   Context -- theory management operations (name, identity, inclusion,
  6186     parents, ancestors, merge, etc.), plus generic theory data;
  6187 
  6188   Sign -- logical signature and syntax operations (declaring consts,
  6189     types, etc.), plus certify/read for common entities;
  6190 
  6191   Theory -- logical theory operations (stating axioms, definitions,
  6192     oracles), plus a copy of logical signature operations (consts,
  6193     types, etc.); also a few basic management operations (Theory.copy,
  6194     Theory.merge, etc.)
  6195 
  6196 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6197 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6198 for convenience -- they merely return the theory.
  6199 
  6200 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6201 
  6202 * Pure: the Isar proof context type is already defined early in Pure
  6203 as Context.proof (note that ProofContext.context and Proof.context are
  6204 aliases, where the latter is the preferred name).  This enables other
  6205 Isabelle components to refer to that type even before Isar is present.
  6206 
  6207 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6208 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6209 any of these kinds.  For example, Sign.intern typeK is now
  6210 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6211 Theory.hide_types.  Also note that former
  6212 Theory.hide_classes/types/consts are now
  6213 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6214 internalize their arguments!  INCOMPATIBILITY.
  6215 
  6216 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6217 datatype thmref (with constructors Name and NameSelection) instead of
  6218 plain string -- INCOMPATIBILITY;
  6219 
  6220 * Pure: cases produced by proof methods specify options, where NONE
  6221 means to remove case bindings -- INCOMPATIBILITY in
  6222 (RAW_)METHOD_CASES.
  6223 
  6224 * Pure: the following operations retrieve axioms or theorems from a
  6225 theory node or theory hierarchy, respectively:
  6226 
  6227   Theory.axioms_of: theory -> (string * term) list
  6228   Theory.all_axioms_of: theory -> (string * term) list
  6229   PureThy.thms_of: theory -> (string * thm) list
  6230   PureThy.all_thms_of: theory -> (string * thm) list
  6231 
  6232 * Pure: print_tac now outputs the goal through the trace channel.
  6233 
  6234 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6235 Reference Toplevel.debug (default false) controls detailed printing
  6236 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6237 controls execution profiling -- set to 1 for time and 2 for space
  6238 (both increase the runtime).
  6239 
  6240 * Isar session: The initial use of ROOT.ML is now always timed,
  6241 i.e. the log will show the actual process times, in contrast to the
  6242 elapsed wall-clock time that the outer shell wrapper produces.
  6243 
  6244 * Simplifier: improved handling of bound variables (nameless
  6245 representation, avoid allocating new strings).  Simprocs that invoke
  6246 the Simplifier recursively should use Simplifier.inherit_bounds to
  6247 avoid local name clashes.  Failure to do so produces warnings
  6248 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6249 for further details.
  6250 
  6251 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6252 bindings for all theorems stored within a given theory; this may help
  6253 in porting non-Isar theories to Isar ones, while keeping ML proof
  6254 scripts for the time being.
  6255 
  6256 * ML operator HTML.with_charset specifies the charset begin used for
  6257 generated HTML files.  For example:
  6258 
  6259   HTML.with_charset "utf-8" use_thy "Hebrew";
  6260   HTML.with_charset "utf-8" use_thy "Chinese";
  6261 
  6262 
  6263 *** System ***
  6264 
  6265 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6266 isabelle, isatool etc.).
  6267 
  6268 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6269 isatool doc, isatool mkdir, display_drafts etc.).
  6270 
  6271 * isatool usedir: option -f allows specification of the ML file to be
  6272 used by Isabelle; default is ROOT.ML.
  6273 
  6274 * New isatool version outputs the version identifier of the Isabelle
  6275 distribution being used.
  6276 
  6277 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6278 (containing Boolean satisfiability problems) into Isabelle/HOL
  6279 theories.
  6280 
  6281 
  6282 
  6283 New in Isabelle2004 (April 2004)
  6284 --------------------------------
  6285 
  6286 *** General ***
  6287 
  6288 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6289   Replaces linorder.ML.
  6290 
  6291 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6292   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6293   (\<a>...\<z>), are now considered normal letters, and can therefore
  6294   be used anywhere where an ASCII letter (a...zA...Z) has until
  6295   now. COMPATIBILITY: This obviously changes the parsing of some
  6296   terms, especially where a symbol has been used as a binder, say
  6297   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6298   as an identifier.  Fix it by inserting a space around former
  6299   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6300   existing theory and ML files.
  6301 
  6302 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6303 
  6304 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6305   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6306   a normal (but invisible) letter. For multiple letter subscripts repeat
  6307   \<^isub> like this: x\<^isub>1\<^isub>2.
  6308 
  6309 * Pure: There are now sub-/superscripts that can span more than one
  6310   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6311   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6312   superscript. The new control characters are not identifier parts.
  6313 
  6314 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6315   content of "..." to the latex file instead of \isacntrl... . The "..."
  6316   may consist of any printable characters excluding the end bracket >.
  6317 
  6318 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6319   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6320   declare constants "final", which prevents their being given a definition
  6321   later.  It is useful for constants whose behaviour is fixed axiomatically
  6322   rather than definitionally, such as the meta-logic connectives.
  6323 
  6324 * Pure: 'instance' now handles general arities with general sorts
  6325   (i.e. intersections of classes),
  6326 
  6327 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6328   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6329   It can be changed to alter the colors/layout of generated pages.
  6330 
  6331 
  6332 *** Isar ***
  6333 
  6334 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6335   cut_tac, subgoal_tac and thin_tac:
  6336   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6337     locales are no longer forced to write Isar proof scripts.
  6338     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6339     emulations.
  6340   - INCOMPATIBILITY: names of variables to be instantiated may no
  6341     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6342     This is consistent with the instantiation attribute "where".
  6343 
  6344 * Attributes "where" and "of":
  6345   - Now take type variables of instantiated theorem into account when reading
  6346     the instantiation string.  This fixes a bug that caused instantiated
  6347     theorems to have too special types in some circumstances.
  6348   - "where" permits explicit instantiations of type variables.
  6349 
  6350 * Calculation commands "moreover" and "also" no longer interfere with
  6351   current facts ("this"), admitting arbitrary combinations with "then"
  6352   and derived forms.
  6353 
  6354 * Locales:
  6355   - Goal statements involving the context element "includes" no longer
  6356     generate theorems with internal delta predicates (those ending on
  6357     "_axioms") in the premise.
  6358     Resolve particular premise with <locale>.intro to obtain old form.
  6359   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6360     specification and "includes" elements in goal statement.
  6361   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6362     [intro?] and [elim?] (respectively) by default.
  6363   - Experimental command for instantiation of locales in proof contexts:
  6364         instantiate <label>[<attrs>]: <loc>
  6365     Instantiates locale <loc> and adds all its theorems to the current context
  6366     taking into account their attributes.  Label and attrs are optional
  6367     modifiers, like in theorem declarations.  If present, names of
  6368     instantiated theorems are qualified with <label>, and the attributes
  6369     <attrs> are applied after any attributes these theorems might have already.
  6370       If the locale has assumptions, a chained fact of the form
  6371     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6372     are derived.  The command does not support old-style locales declared
  6373     with "locale (open)".
  6374       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6375 
  6376 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6377   (Isar) contexts.
  6378 
  6379 
  6380 *** HOL ***
  6381 
  6382 * Proof import: new image HOL4 contains the imported library from
  6383   the HOL4 system with about 2500 theorems. It is imported by
  6384   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6385   can be used like any other Isabelle image.  See
  6386   HOL/Import/HOL/README for more information.
  6387 
  6388 * Simplifier:
  6389   - Much improved handling of linear and partial orders.
  6390     Reasoners for linear and partial orders are set up for type classes
  6391     "linorder" and "order" respectively, and are added to the default simpset
  6392     as solvers.  This means that the simplifier can build transitivity chains
  6393     to solve goals from the assumptions.
  6394   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6395     of blast or auto after simplification become unnecessary because the goal
  6396     is solved by simplification already.
  6397 
  6398 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6399     all proved in axiomatic type classes for semirings, rings and fields.
  6400 
  6401 * Numerics:
  6402   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6403     now formalized using the Ring_and_Field theory mentioned above.
  6404   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6405     than before, because now they are set up once in a generic manner.
  6406   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6407     Look for the general versions in Ring_and_Field (and Power if they concern
  6408     exponentiation).
  6409 
  6410 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6411 
  6412 * Records:
  6413   - Record types are now by default printed with their type abbreviation
  6414     instead of the list of all field types. This can be configured via
  6415     the reference "print_record_type_abbr".
  6416   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6417     (not enabled by default).
  6418   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6419     EX x. x = sel r to True (not enabled by default).
  6420   - Tactic "record_split_simp_tac" to split and simplify records added.
  6421 
  6422 * 'specification' command added, allowing for definition by
  6423   specification.  There is also an 'ax_specification' command that
  6424   introduces the new constants axiomatically.
  6425 
  6426 * arith(_tac) is now able to generate counterexamples for reals as well.
  6427 
  6428 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6429 
  6430 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6431   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6432 
  6433 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6434   matrix theory to linear programming.
  6435 
  6436 * Unions and Intersections:
  6437   The latex output syntax of UN and INT has been changed
  6438   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6439   i.e. the index formulae has become a subscript.
  6440   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6441 
  6442 * Unions and Intersections over Intervals:
  6443   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6444   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6445   like in normal math, and corresponding versions for < and for intersection.
  6446 
  6447 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6448   lexicographic dictonary ordering has been added as "lexord".
  6449 
  6450 * ML: the legacy theory structures Int and List have been removed. They had
  6451   conflicted with ML Basis Library structures having the same names.
  6452 
  6453 * 'refute' command added to search for (finite) countermodels.  Only works
  6454   for a fragment of HOL.  The installation of an external SAT solver is
  6455   highly recommended.  See "HOL/Refute.thy" for details.
  6456 
  6457 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6458   formulae under an assignment of free variables to random values.
  6459   In contrast to 'refute', it can deal with inductive datatypes,
  6460   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6461   for examples.
  6462 
  6463 
  6464 *** HOLCF ***
  6465 
  6466 * Streams now come with concatenation and are part of the HOLCF image
  6467 
  6468 
  6469 
  6470 New in Isabelle2003 (May 2003)
  6471 ------------------------------
  6472 
  6473 *** General ***
  6474 
  6475 * Provers/simplifier:
  6476 
  6477   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6478     Assumptions are now subject to complete mutual simplification,
  6479     not just from left to right. The simplifier now preserves
  6480     the order of assumptions.
  6481 
  6482     Potential INCOMPATIBILITY:
  6483 
  6484     -- simp sometimes diverges where the old version did
  6485        not, e.g. invoking simp on the goal
  6486 
  6487         [| P (f x); y = x; f x = f y |] ==> Q
  6488 
  6489        now gives rise to the infinite reduction sequence
  6490 
  6491         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6492 
  6493        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6494        kind of problem.
  6495 
  6496     -- Tactics combining classical reasoner and simplification (such as auto)
  6497        are also affected by this change, because many of them rely on
  6498        simp. They may sometimes diverge as well or yield a different numbers
  6499        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6500        in case of problems. Sometimes subsequent calls to the classical
  6501        reasoner will fail because a preceeding call to the simplifier too
  6502        eagerly simplified the goal, e.g. deleted redundant premises.
  6503 
  6504   - The simplifier trace now shows the names of the applied rewrite rules
  6505 
  6506   - You can limit the number of recursive invocations of the simplifier
  6507     during conditional rewriting (where the simplifie tries to solve the
  6508     conditions before applying the rewrite rule):
  6509     ML "simp_depth_limit := n"
  6510     where n is an integer. Thus you can force termination where previously
  6511     the simplifier would diverge.
  6512 
  6513   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6514 
  6515   - No longer aborts on failed congruence proof.  Instead, the
  6516     congruence is ignored.
  6517 
  6518 * Pure: New generic framework for extracting programs from constructive
  6519   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6520   as HOL/Extraction for some case studies.
  6521 
  6522 * Pure: The main goal of the proof state is no longer shown by default, only
  6523 the subgoals. This behaviour is controlled by a new flag.
  6524    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6525 (ML: Proof.show_main_goal).
  6526 
  6527 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6528 rules whose conclusion matches subgoal 1:
  6529       PG menu: Isabelle/Isar -> Show me -> matching rules
  6530 The rules are ordered by how closely they match the subgoal.
  6531 In particular, rules that solve a subgoal outright are displayed first
  6532 (or rather last, the way they are printed).
  6533 (ML: ProofGeneral.print_intros())
  6534 
  6535 * Pure: New flag trace_unify_fail causes unification to print
  6536 diagnostic information (PG: in trace buffer) when it fails. This is
  6537 useful for figuring out why single step proofs like rule, erule or
  6538 assumption failed.
  6539 
  6540 * Pure: Locale specifications now produce predicate definitions
  6541 according to the body of text (covering assumptions modulo local
  6542 definitions); predicate "loc_axioms" covers newly introduced text,
  6543 while "loc" is cumulative wrt. all included locale expressions; the
  6544 latter view is presented only on export into the global theory
  6545 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6546 on the old view without predicates;
  6547 
  6548 * Pure: predefined locales "var" and "struct" are useful for sharing
  6549 parameters (as in CASL, for example); just specify something like
  6550 ``var x + var y + struct M'' as import;
  6551 
  6552 * Pure: improved thms_containing: proper indexing of facts instead of
  6553 raw theorems; check validity of results wrt. current name space;
  6554 include local facts of proof configuration (also covers active
  6555 locales), cover fixed variables in index; may use "_" in term
  6556 specification; an optional limit for the number of printed facts may
  6557 be given (the default is 40);
  6558 
  6559 * Pure: disallow duplicate fact bindings within new-style theory files
  6560 (batch-mode only);
  6561 
  6562 * Provers: improved induct method: assumptions introduced by case
  6563 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6564 the goal statement); "foo" still refers to all facts collectively;
  6565 
  6566 * Provers: the function blast.overloaded has been removed: all constants
  6567 are regarded as potentially overloaded, which improves robustness in exchange
  6568 for slight decrease in efficiency;
  6569 
  6570 * Provers/linorder: New generic prover for transitivity reasoning over
  6571 linear orders.  Note: this prover is not efficient!
  6572 
  6573 * Isar: preview of problems to finish 'show' now produce an error
  6574 rather than just a warning (in interactive mode);
  6575 
  6576 
  6577 *** HOL ***
  6578 
  6579 * arith(_tac)
  6580 
  6581  - Produces a counter example if it cannot prove a goal.
  6582    Note that the counter example may be spurious if the goal is not a formula
  6583    of quantifier-free linear arithmetic.
  6584    In ProofGeneral the counter example appears in the trace buffer.
  6585 
  6586  - Knows about div k and mod k where k is a numeral of type nat or int.
  6587 
  6588  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6589    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6590    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6591 
  6592 * simp's arithmetic capabilities have been enhanced a bit: it now
  6593 takes ~= in premises into account (by performing a case split);
  6594 
  6595 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6596 are distributed over a sum of terms;
  6597 
  6598 * New tactic "trans_tac" and method "trans" instantiate
  6599 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6600 "<=", "<" and "=").
  6601 
  6602 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6603 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6604 
  6605 * 'typedef' command has new option "open" to suppress the set
  6606 definition;
  6607 
  6608 * functions Min and Max on finite sets have been introduced (theory
  6609 Finite_Set);
  6610 
  6611 * attribute [symmetric] now works for relations as well; it turns
  6612 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6613 
  6614 * induct over a !!-quantified statement (say !!x1..xn):
  6615   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6616 
  6617 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6618 %x. None. Warning: empty_def now refers to the previously hidden definition
  6619 of the empty set.
  6620 
  6621 * Algebra: formalization of classical algebra.  Intended as base for
  6622 any algebraic development in Isabelle.  Currently covers group theory
  6623 (up to Sylow's theorem) and ring theory (Universal Property of
  6624 Univariate Polynomials).  Contributions welcome;
  6625 
  6626 * GroupTheory: deleted, since its material has been moved to Algebra;
  6627 
  6628 * Complex: new directory of the complex numbers with numeric constants,
  6629 nonstandard complex numbers, and some complex analysis, standard and
  6630 nonstandard (Jacques Fleuriot);
  6631 
  6632 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6633 
  6634 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6635 Fleuriot);
  6636 
  6637 * Real/HahnBanach: updated and adapted to locales;
  6638 
  6639 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6640 Gray and Kramer);
  6641 
  6642 * UNITY: added the Meier-Sanders theory of progress sets;
  6643 
  6644 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6645 as abstract algorithms, instantiated to the JVM;
  6646 
  6647 * Bali: Java source language formalization. Type system, operational
  6648 semantics, axiomatic semantics. Supported language features:
  6649 classes, interfaces, objects,virtual methods, static methods,
  6650 static/instance fields, arrays, access modifiers, definite
  6651 assignment, exceptions.
  6652 
  6653 
  6654 *** ZF ***
  6655 
  6656 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6657 universe, etc.);
  6658 
  6659 * Main ZF: virtually all theories converted to new-style format;
  6660 
  6661 
  6662 *** ML ***
  6663 
  6664 * Pure: Tactic.prove provides sane interface for internal proofs;
  6665 omits the infamous "standard" operation, so this is more appropriate
  6666 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6667 
  6668 * Pure: improved error reporting of simprocs;
  6669 
  6670 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6671 up simprocs;
  6672 
  6673 
  6674 *** Document preparation ***
  6675 
  6676 * uses \par instead of \\ for line breaks in theory text. This may
  6677 shift some page breaks in large documents. To get the old behaviour
  6678 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6679 
  6680 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6681 other packages
  6682 
  6683 * \<euro> now needs package babel/greek instead of marvosym (which
  6684 broke \Rightarrow)
  6685 
  6686 * normal size for \<zero>...\<nine> (uses \mathbf instead of
  6687 textcomp package)
  6688 
  6689 
  6690 
  6691 New in Isabelle2002 (March 2002)
  6692 --------------------------------
  6693 
  6694 *** Document preparation ***
  6695 
  6696 * greatly simplified document preparation setup, including more
  6697 graceful interpretation of isatool usedir -i/-d/-D options, and more
  6698 instructive isatool mkdir; users should basically be able to get
  6699 started with "isatool mkdir HOL Test && isatool make"; alternatively,
  6700 users may run a separate document processing stage manually like this:
  6701 "isatool usedir -D output HOL Test && isatool document Test/output";
  6702 
  6703 * theory dependency graph may now be incorporated into documents;
  6704 isatool usedir -g true will produce session_graph.eps/.pdf for use
  6705 with \includegraphics of LaTeX;
  6706 
  6707 * proper spacing of consecutive markup elements, especially text
  6708 blocks after section headings;
  6709 
  6710 * support bold style (for single symbols only), input syntax is like
  6711 this: "\<^bold>\<alpha>" or "\<^bold>A";
  6712 
  6713 * \<bullet> is now output as bold \cdot by default, which looks much
  6714 better in printed text;
  6715 
  6716 * added default LaTeX bindings for \<tturnstile> and \<TTurnstile>;
  6717 note that these symbols are currently unavailable in Proof General /
  6718 X-Symbol; new symbols \<zero>, \<one>, ..., \<nine>, and \<euro>;
  6719 
  6720 * isatool latex no longer depends on changed TEXINPUTS, instead
  6721 isatool document copies the Isabelle style files to the target
  6722 location;
  6723 
  6724 
  6725 *** Isar ***
  6726 
  6727 * Pure/Provers: improved proof by cases and induction;
  6728   - 'case' command admits impromptu naming of parameters (such as
  6729     "case (Suc n)");
  6730   - 'induct' method divinates rule instantiation from the inductive
  6731     claim; no longer requires excessive ?P bindings for proper
  6732     instantiation of cases;
  6733   - 'induct' method properly enumerates all possibilities of set/type
  6734     rules; as a consequence facts may be also passed through *type*
  6735     rules without further ado;
  6736   - 'induct' method now derives symbolic cases from the *rulified*
  6737     rule (before it used to rulify cases stemming from the internal
  6738     atomized version); this means that the context of a non-atomic
  6739     statement becomes is included in the hypothesis, avoiding the
  6740     slightly cumbersome show "PROP ?case" form;
  6741   - 'induct' may now use elim-style induction rules without chaining
  6742     facts, using ``missing'' premises from the goal state; this allows
  6743     rules stemming from inductive sets to be applied in unstructured
  6744     scripts, while still benefitting from proper handling of non-atomic
  6745     statements; NB: major inductive premises need to be put first, all
  6746     the rest of the goal is passed through the induction;
  6747   - 'induct' proper support for mutual induction involving non-atomic
  6748     rule statements (uses the new concept of simultaneous goals, see
  6749     below);
  6750   - append all possible rule selections, but only use the first
  6751     success (no backtracking);
  6752   - removed obsolete "(simplified)" and "(stripped)" options of methods;
  6753   - undeclared rule case names default to numbers 1, 2, 3, ...;
  6754   - added 'print_induct_rules' (covered by help item in recent Proof
  6755     General versions);
  6756   - moved induct/cases attributes to Pure, methods to Provers;
  6757   - generic method setup instantiated for FOL and HOL;
  6758 
  6759 * Pure: support multiple simultaneous goal statements, for example
  6760 "have a: A and b: B" (same for 'theorem' etc.); being a pure
  6761 meta-level mechanism, this acts as if several individual goals had
  6762 been stated separately; in particular common proof methods need to be
  6763 repeated in order to cover all claims; note that a single elimination
  6764 step is *not* sufficient to establish the two conjunctions, so this
  6765 fails:
  6766 
  6767   assume "A & B" then have A and B ..   (*".." fails*)
  6768 
  6769 better use "obtain" in situations as above; alternative refer to
  6770 multi-step methods like 'auto', 'simp_all', 'blast+' etc.;
  6771 
  6772 * Pure: proper integration with ``locales''; unlike the original
  6773 version by Florian Kammller, Isar locales package high-level proof
  6774 contexts rather than raw logical ones (e.g. we admit to include
  6775 attributes everywhere); operations on locales include merge and
  6776 rename; support for implicit arguments (``structures''); simultaneous
  6777 type-inference over imports and text; see also HOL/ex/Locales.thy for
  6778 some examples;
  6779 
  6780 * Pure: the following commands have been ``localized'', supporting a
  6781 target locale specification "(in name)": 'lemma', 'theorem',
  6782 'corollary', 'lemmas', 'theorems', 'declare'; the results will be
  6783 stored both within the locale and at the theory level (exported and
  6784 qualified by the locale name);
  6785 
  6786 * Pure: theory goals may now be specified in ``long'' form, with
  6787 ad-hoc contexts consisting of arbitrary locale elements. for example
  6788 ``lemma foo: fixes x assumes "A x" shows "B x"'' (local syntax and
  6789 definitions may be given, too); the result is a meta-level rule with
  6790 the context elements being discharged in the obvious way;
  6791 
  6792 * Pure: new proof command 'using' allows to augment currently used
  6793 facts after a goal statement ('using' is syntactically analogous to
  6794 'apply', but acts on the goal's facts only); this allows chained facts
  6795 to be separated into parts given before and after a claim, as in
  6796 ``from a and b have C using d and e <proof>'';
  6797 
  6798 * Pure: renamed "antecedent" case to "rule_context";
  6799 
  6800 * Pure: new 'judgment' command records explicit information about the
  6801 object-logic embedding (used by several tools internally); no longer
  6802 use hard-wired "Trueprop";
  6803 
  6804 * Pure: added 'corollary' command;
  6805 
  6806 * Pure: fixed 'token_translation' command;
  6807 
  6808 * Pure: removed obsolete 'exported' attribute;
  6809 
  6810 * Pure: dummy pattern "_" in is/let is now automatically lifted over
  6811 bound variables: "ALL x. P x --> Q x" (is "ALL x. _ --> ?C x")
  6812 supersedes more cumbersome ... (is "ALL x. _ x --> ?C x");
  6813 
  6814 * Pure: method 'atomize' presents local goal premises as object-level
  6815 statements (atomic meta-level propositions); setup controlled via
  6816 rewrite rules declarations of 'atomize' attribute; example
  6817 application: 'induct' method with proper rule statements in improper
  6818 proof *scripts*;
  6819 
  6820 * Pure: emulation of instantiation tactics (rule_tac, cut_tac, etc.)
  6821 now consider the syntactic context of assumptions, giving a better
  6822 chance to get type-inference of the arguments right (this is
  6823 especially important for locales);
  6824 
  6825 * Pure: "sorry" no longer requires quick_and_dirty in interactive
  6826 mode;
  6827 
  6828 * Pure/obtain: the formal conclusion "thesis", being marked as
  6829 ``internal'', may no longer be reference directly in the text;
  6830 potential INCOMPATIBILITY, may need to use "?thesis" in rare
  6831 situations;
  6832 
  6833 * Pure: generic 'sym' attribute which declares a rule both as pure
  6834 'elim?' and for the 'symmetric' operation;
  6835 
  6836 * Pure: marginal comments ``--'' may now occur just anywhere in the
  6837 text; the fixed correlation with particular command syntax has been
  6838 discontinued;
  6839 
  6840 * Pure: new method 'rules' is particularly well-suited for proof
  6841 search in intuitionistic logic; a bit slower than 'blast' or 'fast',
  6842 but often produces more compact proof terms with less detours;
  6843 
  6844 * Pure/Provers/classical: simplified integration with pure rule
  6845 attributes and methods; the classical "intro?/elim?/dest?"
  6846 declarations coincide with the pure ones; the "rule" method no longer
  6847 includes classically swapped intros; "intro" and "elim" methods no
  6848 longer pick rules from the context; also got rid of ML declarations
  6849 AddXIs/AddXEs/AddXDs; all of this has some potential for
  6850 INCOMPATIBILITY;
  6851 
  6852 * Provers/classical: attribute 'swapped' produces classical inversions
  6853 of introduction rules;
  6854 
  6855 * Provers/simplifier: 'simplified' attribute may refer to explicit
  6856 rules instead of full simplifier context; 'iff' attribute handles
  6857 conditional rules;
  6858 
  6859 * HOL: 'typedef' now allows alternative names for Rep/Abs morphisms;
  6860 
  6861 * HOL: 'recdef' now fails on unfinished automated proofs, use
  6862 "(permissive)" option to recover old behavior;
  6863 
  6864 * HOL: 'inductive' no longer features separate (collective) attributes
  6865 for 'intros' (was found too confusing);
  6866 
  6867 * HOL: properly declared induction rules less_induct and
  6868 wf_induct_rule;
  6869 
  6870 
  6871 *** HOL ***
  6872 
  6873 * HOL: moved over to sane numeral syntax; the new policy is as
  6874 follows:
  6875 
  6876   - 0 and 1 are polymorphic constants, which are defined on any
  6877   numeric type (nat, int, real etc.);
  6878 
  6879   - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
  6880   binary representation internally;
  6881 
  6882   - type nat has special constructor Suc, and generally prefers Suc 0
  6883   over 1::nat and Suc (Suc 0) over 2::nat;
  6884 
  6885 This change may cause significant problems of INCOMPATIBILITY; here
  6886 are some hints on converting existing sources:
  6887 
  6888   - due to the new "num" token, "-0" and "-1" etc. are now atomic
  6889   entities, so expressions involving "-" (unary or binary minus) need
  6890   to be spaced properly;
  6891 
  6892   - existing occurrences of "1" may need to be constraint "1::nat" or
  6893   even replaced by Suc 0; similar for old "2";
  6894 
  6895   - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
  6896 
  6897   - remove all special provisions on numerals in proofs;
  6898 
  6899 * HOL: simp rules nat_number expand numerals on nat to Suc/0
  6900 representation (depends on bin_arith_simps in the default context);
  6901 
  6902 * HOL: symbolic syntax for x^2 (numeral 2);
  6903 
  6904 * HOL: the class of all HOL types is now called "type" rather than
  6905 "term"; INCOMPATIBILITY, need to adapt references to this type class
  6906 in axclass/classes, instance/arities, and (usually rare) occurrences
  6907 in typings (of consts etc.); internally the class is called
  6908 "HOL.type", ML programs should refer to HOLogic.typeS;
  6909 
  6910 * HOL/record package improvements:
  6911   - new derived operations "fields" to build a partial record section,
  6912     "extend" to promote a fixed record to a record scheme, and
  6913     "truncate" for the reverse; cf. theorems "xxx.defs", which are *not*
  6914     declared as simp by default;
  6915   - shared operations ("more", "fields", etc.) now need to be always
  6916     qualified) --- potential INCOMPATIBILITY;
  6917   - removed "make_scheme" operations (use "make" with "extend") --
  6918     INCOMPATIBILITY;
  6919   - removed "more" class (simply use "term") -- INCOMPATIBILITY;
  6920   - provides cases/induct rules for use with corresponding Isar
  6921     methods (for concrete records, record schemes, concrete more
  6922     parts, and schematic more parts -- in that order);
  6923   - internal definitions directly based on a light-weight abstract
  6924     theory of product types over typedef rather than datatype;
  6925 
  6926 * HOL: generic code generator for generating executable ML code from
  6927 specifications; specific support for HOL constructs such as inductive
  6928 datatypes and sets, as well as recursive functions; can be invoked
  6929 via 'generate_code' theory section;
  6930 
  6931 * HOL: canonical cases/induct rules for n-tuples (n = 3..7);
  6932 
  6933 * HOL: consolidated and renamed several theories.  In particular:
  6934         Ord.thy has been absorbed into HOL.thy
  6935         String.thy has been absorbed into List.thy
  6936 
  6937 * HOL: concrete setsum syntax "\<Sum>i:A. b" == "setsum (%i. b) A"
  6938 (beware of argument permutation!);
  6939 
  6940 * HOL: linorder_less_split superseded by linorder_cases;
  6941 
  6942 * HOL/List: "nodups" renamed to "distinct";
  6943 
  6944 * HOL: added "The" definite description operator; move Hilbert's "Eps"
  6945 to peripheral theory "Hilbert_Choice"; some INCOMPATIBILITIES:
  6946   - Ex_def has changed, now need to use some_eq_ex
  6947 
  6948 * HOL: made split_all_tac safe; EXISTING PROOFS MAY FAIL OR LOOP, so
  6949 in this (rare) case use:
  6950 
  6951   delSWrapper "split_all_tac"
  6952   addSbefore ("unsafe_split_all_tac", unsafe_split_all_tac)
  6953 
  6954 * HOL: added safe wrapper "split_conv_tac" to claset; EXISTING PROOFS
  6955 MAY FAIL;
  6956 
  6957 * HOL: introduced f^n = f o ... o f; warning: due to the limits of
  6958 Isabelle's type classes, ^ on functions and relations has too general
  6959 a domain, namely ('a * 'b) set and 'a => 'b; this means that it may be
  6960 necessary to attach explicit type constraints;
  6961 
  6962 * HOL/Relation: the prefix name of the infix "O" has been changed from
  6963 "comp" to "rel_comp"; INCOMPATIBILITY: a few theorems have been
  6964 renamed accordingly (eg "compI" -> "rel_compI").
  6965 
  6966 * HOL: syntax translations now work properly with numerals and records
  6967 expressions;
  6968 
  6969 * HOL: bounded abstraction now uses syntax "%" / "\<lambda>" instead
  6970 of "lam" -- INCOMPATIBILITY;
  6971 
  6972 * HOL: got rid of some global declarations (potential INCOMPATIBILITY
  6973 for ML tools): const "()" renamed "Product_Type.Unity", type "unit"
  6974 renamed "Product_Type.unit";
  6975 
  6976 * HOL: renamed rtrancl_into_rtrancl2 to converse_rtrancl_into_rtrancl
  6977 
  6978 * HOL: removed obsolete theorem "optionE" (use "option.exhaust", or
  6979 the "cases" method);
  6980 
  6981 * HOL/GroupTheory: group theory examples including Sylow's theorem (by
  6982 Florian Kammller);
  6983 
  6984 * HOL/IMP: updated and converted to new-style theory format; several
  6985 parts turned into readable document, with proper Isar proof texts and
  6986 some explanations (by Gerwin Klein);
  6987 
  6988 * HOL-Real: added Complex_Numbers (by Gertrud Bauer);
  6989 
  6990 * HOL-Hyperreal is now a logic image;
  6991 
  6992 
  6993 *** HOLCF ***
  6994 
  6995 * Isar: consts/constdefs supports mixfix syntax for continuous
  6996 operations;
  6997 
  6998 * Isar: domain package adapted to new-style theory format, e.g. see
  6999 HOLCF/ex/Dnat.thy;
  7000 
  7001 * theory Lift: proper use of rep_datatype lift instead of ML hacks --
  7002 potential INCOMPATIBILITY; now use plain induct_tac instead of former
  7003 lift.induct_tac, always use UU instead of Undef;
  7004 
  7005 * HOLCF/IMP: updated and converted to new-style theory;
  7006 
  7007 
  7008 *** ZF ***
  7009 
  7010 * Isar: proper integration of logic-specific tools and packages,
  7011 including theory commands '(co)inductive', '(co)datatype',
  7012 'rep_datatype', 'inductive_cases', as well as methods 'ind_cases',
  7013 'induct_tac', 'case_tac', and 'typecheck' (with attribute 'TC');
  7014 
  7015 * theory Main no longer includes AC; for the Axiom of Choice, base
  7016 your theory on Main_ZFC;
  7017 
  7018 * the integer library now covers quotients and remainders, with many
  7019 laws relating division to addition, multiplication, etc.;
  7020 
  7021 * ZF/UNITY: Chandy and Misra's UNITY is now available in ZF, giving a
  7022 typeless version of the formalism;
  7023 
  7024 * ZF/AC, Coind, IMP, Resid: updated and converted to new-style theory
  7025 format;
  7026 
  7027 * ZF/Induct: new directory for examples of inductive definitions,
  7028 including theory Multiset for multiset orderings; converted to
  7029 new-style theory format;
  7030 
  7031 * ZF: many new theorems about lists, ordinals, etc.;
  7032 
  7033 
  7034 *** General ***
  7035 
  7036 * Pure/kernel: meta-level proof terms (by Stefan Berghofer); reference
  7037 variable proof controls level of detail: 0 = no proofs (only oracle
  7038 dependencies), 1 = lemma dependencies, 2 = compact proof terms; see
  7039 also ref manual for further ML interfaces;
  7040 
  7041 * Pure/axclass: removed obsolete ML interface
  7042 goal_subclass/goal_arity;
  7043 
  7044 * Pure/syntax: new token syntax "num" for plain numerals (without "#"
  7045 of "xnum"); potential INCOMPATIBILITY, since -0, -1 etc. are now
  7046 separate tokens, so expressions involving minus need to be spaced
  7047 properly;
  7048 
  7049 * Pure/syntax: support non-oriented infixes, using keyword "infix"
  7050 rather than "infixl" or "infixr";
  7051 
  7052 * Pure/syntax: concrete syntax for dummy type variables admits genuine
  7053 sort constraint specifications in type inference; e.g. "x::_::foo"
  7054 ensures that the type of "x" is of sort "foo" (but not necessarily a
  7055 type variable);
  7056 
  7057 * Pure/syntax: print modes "type_brackets" and "no_type_brackets"
  7058 control output of nested => (types); the default behavior is
  7059 "type_brackets";
  7060 
  7061 * Pure/syntax: builtin parse translation for "_constify" turns valued
  7062 tokens into AST constants;
  7063 
  7064 * Pure/syntax: prefer later declarations of translations and print
  7065 translation functions; potential INCOMPATIBILITY: need to reverse
  7066 multiple declarations for same syntax element constant;
  7067 
  7068 * Pure/show_hyps reset by default (in accordance to existing Isar
  7069 practice);
  7070 
  7071 * Provers/classical: renamed addaltern to addafter, addSaltern to
  7072 addSafter;
  7073 
  7074 * Provers/clasimp: ``iff'' declarations now handle conditional rules
  7075 as well;
  7076 
  7077 * system: tested support for MacOS X; should be able to get Isabelle +
  7078 Proof General to work in a plain Terminal after installing Poly/ML
  7079 (e.g. from the Isabelle distribution area) and GNU bash alone
  7080 (e.g. from http://www.apple.com); full X11, XEmacs and X-Symbol
  7081 support requires further installations, e.g. from
  7082 http://fink.sourceforge.net/);
  7083 
  7084 * system: support Poly/ML 4.1.1 (able to manage larger heaps);
  7085 
  7086 * system: reduced base memory usage by Poly/ML (approx. 20 MB instead
  7087 of 40 MB), cf. ML_OPTIONS;
  7088 
  7089 * system: Proof General keywords specification is now part of the
  7090 Isabelle distribution (see etc/isar-keywords.el);
  7091 
  7092 * system: support for persistent Proof General sessions (refrain from
  7093 outdating all loaded theories on startup); user may create writable
  7094 logic images like this: ``isabelle -q HOL Test'';
  7095 
  7096 * system: smart selection of Isabelle process versus Isabelle
  7097 interface, accommodates case-insensitive file systems (e.g. HFS+); may
  7098 run both "isabelle" and "Isabelle" even if file names are badly
  7099 damaged (executable inspects the case of the first letter of its own
  7100 name); added separate "isabelle-process" and "isabelle-interface";
  7101 
  7102 * system: refrain from any attempt at filtering input streams; no
  7103 longer support ``8bit'' encoding of old isabelle font, instead proper
  7104 iso-latin characters may now be used; the related isatools
  7105 "symbolinput" and "nonascii" have disappeared as well;
  7106 
  7107 * system: removed old "xterm" interface (the print modes "xterm" and
  7108 "xterm_color" are still available for direct use in a suitable
  7109 terminal);
  7110 
  7111 
  7112 
  7113 New in Isabelle99-2 (February 2001)
  7114 -----------------------------------
  7115 
  7116 *** Overview of INCOMPATIBILITIES ***
  7117 
  7118 * HOL: please note that theories in the Library and elsewhere often use the
  7119 new-style (Isar) format; to refer to their theorems in an ML script you must
  7120 bind them to ML identifers by e.g.      val thm_name = thm "thm_name";
  7121 
  7122 * HOL: inductive package no longer splits induction rule aggressively,
  7123 but only as far as specified by the introductions given; the old
  7124 format may be recovered via ML function complete_split_rule or attribute
  7125 'split_rule (complete)';
  7126 
  7127 * HOL: induct renamed to lfp_induct, lfp_Tarski to lfp_unfold,
  7128 gfp_Tarski to gfp_unfold;
  7129 
  7130 * HOL: contrapos, contrapos2 renamed to contrapos_nn, contrapos_pp;
  7131 
  7132 * HOL: infix "dvd" now has priority 50 rather than 70 (because it is a
  7133 relation); infix "^^" has been renamed "``"; infix "``" has been
  7134 renamed "`"; "univalent" has been renamed "single_valued";
  7135 
  7136 * HOL/Real: "rinv" and "hrinv" replaced by overloaded "inverse"
  7137 operation;
  7138 
  7139 * HOLCF: infix "`" has been renamed "$"; the symbol syntax is \<cdot>;
  7140 
  7141 * Isar: 'obtain' no longer declares "that" fact as simp/intro;
  7142 
  7143 * Isar/HOL: method 'induct' now handles non-atomic goals; as a
  7144 consequence, it is no longer monotonic wrt. the local goal context
  7145 (which is now passed through the inductive cases);
  7146 
  7147 * Document preparation: renamed standard symbols \<ll> to \<lless> and
  7148 \<gg> to \<ggreater>;
  7149 
  7150 
  7151 *** Document preparation ***
  7152 
  7153 * \isabellestyle{NAME} selects version of Isabelle output (currently
  7154 available: are "it" for near math-mode best-style output, "sl" for
  7155 slanted text style, and "tt" for plain type-writer; if no
  7156 \isabellestyle command is given, output is according to slanted
  7157 type-writer);
  7158 
  7159 * support sub/super scripts (for single symbols only), input syntax is
  7160 like this: "A\<^sup>*" or "A\<^sup>\<star>";
  7161 
  7162 * some more standard symbols; see Appendix A of the system manual for
  7163 the complete list of symbols defined in isabellesym.sty;
  7164 
  7165 * improved isabelle style files; more abstract symbol implementation
  7166 (should now use \isamath{...} and \isatext{...} in custom symbol
  7167 definitions);
  7168 
  7169 * antiquotation @{goals} and @{subgoals} for output of *dynamic* goals
  7170 state; Note that presentation of goal states does not conform to
  7171 actual human-readable proof documents.  Please do not include goal
  7172 states into document output unless you really know what you are doing!
  7173 
  7174 * proper indentation of antiquoted output with proportional LaTeX
  7175 fonts;
  7176 
  7177 * no_document ML operator temporarily disables LaTeX document
  7178 generation;
  7179 
  7180 * isatool unsymbolize tunes sources for plain ASCII communication;
  7181 
  7182 
  7183 *** Isar ***
  7184 
  7185 * Pure: Isar now suffers initial goal statements to contain unbound
  7186 schematic variables (this does not conform to actual readable proof
  7187 documents, due to unpredictable outcome and non-compositional proof
  7188 checking); users who know what they are doing may use schematic goals
  7189 for Prolog-style synthesis of proven results;
  7190 
  7191 * Pure: assumption method (an implicit finishing) now handles actual
  7192 rules as well;
  7193 
  7194 * Pure: improved 'obtain' --- moved to Pure, insert "that" into
  7195 initial goal, declare "that" only as Pure intro (only for single
  7196 steps); the "that" rule assumption may now be involved in implicit
  7197 finishing, thus ".." becomes a feasible for trivial obtains;
  7198 
  7199 * Pure: default proof step now includes 'intro_classes'; thus trivial
  7200 instance proofs may be performed by "..";
  7201 
  7202 * Pure: ?thesis / ?this / "..." now work for pure meta-level
  7203 statements as well;
  7204 
  7205 * Pure: more robust selection of calculational rules;
  7206 
  7207 * Pure: the builtin notion of 'finished' goal now includes the ==-refl
  7208 rule (as well as the assumption rule);
  7209 
  7210 * Pure: 'thm_deps' command visualizes dependencies of theorems and
  7211 lemmas, using the graph browser tool;
  7212 
  7213 * Pure: predict failure of "show" in interactive mode;
  7214 
  7215 * Pure: 'thms_containing' now takes actual terms as arguments;
  7216 
  7217 * HOL: improved method 'induct' --- now handles non-atomic goals
  7218 (potential INCOMPATIBILITY); tuned error handling;
  7219 
  7220 * HOL: cases and induct rules now provide explicit hints about the
  7221 number of facts to be consumed (0 for "type" and 1 for "set" rules);
  7222 any remaining facts are inserted into the goal verbatim;
  7223 
  7224 * HOL: local contexts (aka cases) may now contain term bindings as
  7225 well; the 'cases' and 'induct' methods new provide a ?case binding for
  7226 the result to be shown in each case;
  7227 
  7228 * HOL: added 'recdef_tc' command;
  7229 
  7230 * isatool convert assists in eliminating legacy ML scripts;
  7231 
  7232 
  7233 *** HOL ***
  7234 
  7235 * HOL/Library: a collection of generic theories to be used together
  7236 with main HOL; the theory loader path already includes this directory
  7237 by default; the following existing theories have been moved here:
  7238 HOL/Induct/Multiset, HOL/Induct/Acc (as Accessible_Part), HOL/While
  7239 (as While_Combinator), HOL/Lex/Prefix (as List_Prefix);
  7240 
  7241 * HOL/Unix: "Some aspects of Unix file-system security", a typical
  7242 modelling and verification task performed in Isabelle/HOL +
  7243 Isabelle/Isar + Isabelle document preparation (by Markus Wenzel).
  7244 
  7245 * HOL/Algebra: special summation operator SUM no longer exists, it has
  7246 been replaced by setsum; infix 'assoc' now has priority 50 (like
  7247 'dvd'); axiom 'one_not_zero' has been moved from axclass 'ring' to
  7248 'domain', this makes the theory consistent with mathematical
  7249 literature;
  7250 
  7251 * HOL basics: added overloaded operations "inverse" and "divide"
  7252 (infix "/"), syntax for generic "abs" operation, generic summation
  7253 operator \<Sum>;
  7254 
  7255 * HOL/typedef: simplified package, provide more useful rules (see also
  7256 HOL/subset.thy);
  7257 
  7258 * HOL/datatype: induction rule for arbitrarily branching datatypes is
  7259 now expressed as a proper nested rule (old-style tactic scripts may
  7260 require atomize_strip_tac to cope with non-atomic premises);
  7261 
  7262 * HOL: renamed theory "Prod" to "Product_Type", renamed "split" rule
  7263 to "split_conv" (old name still available for compatibility);
  7264 
  7265 * HOL: improved concrete syntax for strings (e.g. allows translation
  7266 rules with string literals);
  7267 
  7268 * HOL-Real-Hyperreal: this extends HOL-Real with the hyperreals
  7269  and Fleuriot's mechanization of analysis, including the transcendental
  7270  functions for the reals;
  7271 
  7272 * HOL/Real, HOL/Hyperreal: improved arithmetic simplification;
  7273 
  7274 
  7275 *** CTT ***
  7276 
  7277 * CTT: x-symbol support for Pi, Sigma, -->, : (membership); note that
  7278 "lam" is displayed as TWO lambda-symbols
  7279 
  7280 * CTT: theory Main now available, containing everything (that is, Bool
  7281 and Arith);
  7282 
  7283 
  7284 *** General ***
  7285 
  7286 * Pure: the Simplifier has been implemented properly as a derived rule
  7287 outside of the actual kernel (at last!); the overall performance
  7288 penalty in practical applications is about 50%, while reliability of
  7289 the Isabelle inference kernel has been greatly improved;
  7290 
  7291 * print modes "brackets" and "no_brackets" control output of nested =>
  7292 (types) and ==> (props); the default behaviour is "brackets";
  7293 
  7294 * Provers: fast_tac (and friends) now handle actual object-logic rules
  7295 as assumptions as well;
  7296 
  7297 * system: support Poly/ML 4.0;
  7298 
  7299 * system: isatool install handles KDE version 1 or 2;
  7300 
  7301 
  7302 
  7303 New in Isabelle99-1 (October 2000)
  7304 ----------------------------------
  7305 
  7306 *** Overview of INCOMPATIBILITIES ***
  7307 
  7308 * HOL: simplification of natural numbers is much changed; to partly
  7309 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
  7310 issue the following ML commands:
  7311 
  7312   Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
  7313   Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
  7314 
  7315 * HOL: simplification no longer dives into case-expressions; this is
  7316 controlled by "t.weak_case_cong" for each datatype t;
  7317 
  7318 * HOL: nat_less_induct renamed to less_induct;
  7319 
  7320 * HOL: systematic renaming of the SOME (Eps) rules, may use isatool
  7321 fixsome to patch .thy and .ML sources automatically;
  7322 
  7323   select_equality  -> some_equality
  7324   select_eq_Ex     -> some_eq_ex
  7325   selectI2EX       -> someI2_ex
  7326   selectI2         -> someI2
  7327   selectI          -> someI
  7328   select1_equality -> some1_equality
  7329   Eps_sym_eq       -> some_sym_eq_trivial
  7330   Eps_eq           -> some_eq_trivial
  7331 
  7332 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
  7333 
  7334 * HOL: removed obsolete theorem binding expand_if (refer to split_if
  7335 instead);
  7336 
  7337 * HOL: the recursion equations generated by 'recdef' are now called
  7338 f.simps instead of f.rules;
  7339 
  7340 * HOL: qed_spec_mp now also handles bounded ALL as well;
  7341 
  7342 * HOL: 0 is now overloaded, so the type constraint ":: nat" may
  7343 sometimes be needed;
  7344 
  7345 * HOL: the constant for "f``x" is now "image" rather than "op ``";
  7346 
  7347 * HOL: the constant for "f-``x" is now "vimage" rather than "op -``";
  7348 
  7349 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
  7350 product is now "<*>" instead of "Times"; the lexicographic product is
  7351 now "<*lex*>" instead of "**";
  7352 
  7353 * HOL: theory Sexp is now in HOL/Induct examples (it used to be part
  7354 of main HOL, but was unused); better use HOL's datatype package;
  7355 
  7356 * HOL: removed "symbols" syntax for constant "override" of theory Map;
  7357 the old syntax may be recovered as follows:
  7358 
  7359   syntax (symbols)
  7360     override  :: "('a ~=> 'b) => ('a ~=> 'b) => ('a ~=> 'b)"
  7361       (infixl "\\<oplus>" 100)
  7362 
  7363 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7364 
  7365 * HOL/ML: even fewer consts are declared as global (see theories Ord,
  7366 Lfp, Gfp, WF); this only affects ML packages that refer to const names
  7367 internally;
  7368 
  7369 * HOL and ZF: syntax for quotienting wrt an equivalence relation
  7370 changed from A/r to A//r;
  7371 
  7372 * ZF: new treatment of arithmetic (nat & int) may break some old
  7373 proofs;
  7374 
  7375 * Isar: renamed some attributes (RS -> THEN, simplify -> simplified,
  7376 rulify -> rule_format, elimify -> elim_format, ...);
  7377 
  7378 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7379 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
  7380 should have to change intro!! to intro? only); replaced "delrule" by
  7381 "rule del";
  7382 
  7383 * Isar/HOL: renamed "intrs" to "intros" in inductive definitions;
  7384 
  7385 * Provers: strengthened force_tac by using new first_best_tac;
  7386 
  7387 * LaTeX document preparation: several changes of isabelle.sty (see
  7388 lib/texinputs);
  7389 
  7390 
  7391 *** Document preparation ***
  7392 
  7393 * formal comments (text blocks etc.) in new-style theories may now
  7394 contain antiquotations of thm/prop/term/typ/text to be presented
  7395 according to latex print mode; concrete syntax is like this:
  7396 @{term[show_types] "f(x) = a + x"};
  7397 
  7398 * isatool mkdir provides easy setup of Isabelle session directories,
  7399 including proper document sources;
  7400 
  7401 * generated LaTeX sources are now deleted after successful run
  7402 (isatool document -c); may retain a copy somewhere else via -D option
  7403 of isatool usedir;
  7404 
  7405 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
  7406 style files, achieving self-contained LaTeX sources and simplifying
  7407 LaTeX debugging;
  7408 
  7409 * old-style theories now produce (crude) LaTeX output as well;
  7410 
  7411 * browser info session directories are now self-contained (may be put
  7412 on WWW server seperately); improved graphs of nested sessions; removed
  7413 graph for 'all sessions';
  7414 
  7415 * several improvements in isabelle style files; \isabellestyle{it}
  7416 produces fake math mode output; \isamarkupheader is now \section by
  7417 default; see lib/texinputs/isabelle.sty etc.;
  7418 
  7419 
  7420 *** Isar ***
  7421 
  7422 * Isar/Pure: local results and corresponding term bindings are now
  7423 subject to Hindley-Milner polymorphism (similar to ML); this
  7424 accommodates incremental type-inference very nicely;
  7425 
  7426 * Isar/Pure: new derived language element 'obtain' supports
  7427 generalized existence reasoning;
  7428 
  7429 * Isar/Pure: new calculational elements 'moreover' and 'ultimately'
  7430 support accumulation of results, without applying any rules yet;
  7431 useful to collect intermediate results without explicit name
  7432 references, and for use with transitivity rules with more than 2
  7433 premises;
  7434 
  7435 * Isar/Pure: scalable support for case-analysis type proofs: new
  7436 'case' language element refers to local contexts symbolically, as
  7437 produced by certain proof methods; internally, case names are attached
  7438 to theorems as "tags";
  7439 
  7440 * Isar/Pure: theory command 'hide' removes declarations from
  7441 class/type/const name spaces;
  7442 
  7443 * Isar/Pure: theory command 'defs' supports option "(overloaded)" to
  7444 indicate potential overloading;
  7445 
  7446 * Isar/Pure: changed syntax of local blocks from {{ }} to { };
  7447 
  7448 * Isar/Pure: syntax of sorts made 'inner', i.e. have to write
  7449 "{a,b,c}" instead of {a,b,c};
  7450 
  7451 * Isar/Pure now provides its own version of intro/elim/dest
  7452 attributes; useful for building new logics, but beware of confusion
  7453 with the version in Provers/classical;
  7454 
  7455 * Isar/Pure: the local context of (non-atomic) goals is provided via
  7456 case name 'antecedent';
  7457 
  7458 * Isar/Pure: removed obsolete 'transfer' attribute (transfer of thms
  7459 to the current context is now done automatically);
  7460 
  7461 * Isar/Pure: theory command 'method_setup' provides a simple interface
  7462 for definining proof methods in ML;
  7463 
  7464 * Isar/Provers: intro/elim/dest attributes changed; renamed
  7465 intro/intro!/intro!! flags to intro!/intro/intro? (INCOMPATIBILITY, in
  7466 most cases, one should have to change intro!! to intro? only);
  7467 replaced "delrule" by "rule del";
  7468 
  7469 * Isar/Provers: new 'hypsubst' method, plain 'subst' method and
  7470 'symmetric' attribute (the latter supercedes [RS sym]);
  7471 
  7472 * Isar/Provers: splitter support (via 'split' attribute and 'simp'
  7473 method modifier); 'simp' method: 'only:' modifier removes loopers as
  7474 well (including splits);
  7475 
  7476 * Isar/Provers: Simplifier and Classical methods now support all kind
  7477 of modifiers used in the past, including 'cong', 'iff', etc.
  7478 
  7479 * Isar/Provers: added 'fastsimp' and 'clarsimp' methods (combination
  7480 of Simplifier and Classical reasoner);
  7481 
  7482 * Isar/HOL: new proof method 'cases' and improved version of 'induct'
  7483 now support named cases; major packages (inductive, datatype, primrec,
  7484 recdef) support case names and properly name parameters;
  7485 
  7486 * Isar/HOL: new transitivity rules for substitution in inequalities --
  7487 monotonicity conditions are extracted to be proven at end of
  7488 calculations;
  7489 
  7490 * Isar/HOL: removed 'case_split' thm binding, should use 'cases' proof
  7491 method anyway;
  7492 
  7493 * Isar/HOL: removed old expand_if = split_if; theorems if_splits =
  7494 split_if split_if_asm; datatype package provides theorems foo.splits =
  7495 foo.split foo.split_asm for each datatype;
  7496 
  7497 * Isar/HOL: tuned inductive package, rename "intrs" to "intros"
  7498 (potential INCOMPATIBILITY), emulation of mk_cases feature for proof
  7499 scripts: new 'inductive_cases' command and 'ind_cases' method; (Note:
  7500 use "(cases (simplified))" method in proper proof texts);
  7501 
  7502 * Isar/HOL: added global 'arith_split' attribute for 'arith' method;
  7503 
  7504 * Isar: names of theorems etc. may be natural numbers as well;
  7505 
  7506 * Isar: 'pr' command: optional arguments for goals_limit and
  7507 ProofContext.prems_limit; no longer prints theory contexts, but only
  7508 proof states;
  7509 
  7510 * Isar: diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
  7511 additional print modes to be specified; e.g. "pr(latex)" will print
  7512 proof state according to the Isabelle LaTeX style;
  7513 
  7514 * Isar: improved support for emulating tactic scripts, including proof
  7515 methods 'rule_tac' etc., 'cut_tac', 'thin_tac', 'subgoal_tac',
  7516 'rename_tac', 'rotate_tac', 'tactic', and 'case_tac' / 'induct_tac'
  7517 (for HOL datatypes);
  7518 
  7519 * Isar: simplified (more robust) goal selection of proof methods: 1st
  7520 goal, all goals, or explicit goal specifier (tactic emulation); thus
  7521 'proof method scripts' have to be in depth-first order;
  7522 
  7523 * Isar: tuned 'let' syntax: replaced 'as' keyword by 'and';
  7524 
  7525 * Isar: removed 'help' command, which hasn't been too helpful anyway;
  7526 should instead use individual commands for printing items
  7527 (print_commands, print_methods etc.);
  7528 
  7529 * Isar: added 'nothing' --- the empty list of theorems;
  7530 
  7531 
  7532 *** HOL ***
  7533 
  7534 * HOL/MicroJava: formalization of a fragment of Java, together with a
  7535 corresponding virtual machine and a specification of its bytecode
  7536 verifier and a lightweight bytecode verifier, including proofs of
  7537 type-safety; by Gerwin Klein, Tobias Nipkow, David von Oheimb, and
  7538 Cornelia Pusch (see also the homepage of project Bali at
  7539 http://isabelle.in.tum.de/Bali/);
  7540 
  7541 * HOL/Algebra: new theory of rings and univariate polynomials, by
  7542 Clemens Ballarin;
  7543 
  7544 * HOL/NumberTheory: fundamental Theorem of Arithmetic, Chinese
  7545 Remainder Theorem, Fermat/Euler Theorem, Wilson's Theorem, by Thomas M
  7546 Rasmussen;
  7547 
  7548 * HOL/Lattice: fundamental concepts of lattice theory and order
  7549 structures, including duals, properties of bounds versus algebraic
  7550 laws, lattice operations versus set-theoretic ones, the Knaster-Tarski
  7551 Theorem for complete lattices etc.; may also serve as a demonstration
  7552 for abstract algebraic reasoning using axiomatic type classes, and
  7553 mathematics-style proof in Isabelle/Isar; by Markus Wenzel;
  7554 
  7555 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog, by David
  7556 von Oheimb;
  7557 
  7558 * HOL/IMPP: extension of IMP with local variables and mutually
  7559 recursive procedures, by David von Oheimb;
  7560 
  7561 * HOL/Lambda: converted into new-style theory and document;
  7562 
  7563 * HOL/ex/Multiquote: example of multiple nested quotations and
  7564 anti-quotations -- basically a generalized version of de-Bruijn
  7565 representation; very useful in avoiding lifting of operations;
  7566 
  7567 * HOL/record: added general record equality rule to simpset; fixed
  7568 select-update simplification procedure to handle extended records as
  7569 well; admit "r" as field name;
  7570 
  7571 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
  7572 other numeric types and also as the identity of groups, rings, etc.;
  7573 
  7574 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
  7575 Types nat and int belong to this axclass;
  7576 
  7577 * HOL: greatly improved simplification involving numerals of type nat, int, real:
  7578    (i + #8 + j) = Suc k simplifies to  #7 + (i + j) = k
  7579    i*j + k + j*#3*i     simplifies to  #4*(i*j) + k
  7580   two terms #m*u and #n*u are replaced by #(m+n)*u
  7581     (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
  7582   and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
  7583     or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
  7584 
  7585 * HOL: meson_tac is available (previously in ex/meson.ML); it is a
  7586 powerful prover for predicate logic but knows nothing of clasets; see
  7587 ex/mesontest.ML and ex/mesontest2.ML for example applications;
  7588 
  7589 * HOL: new version of "case_tac" subsumes both boolean case split and
  7590 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
  7591 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
  7592 
  7593 * HOL: simplification no longer dives into case-expressions: only the
  7594 selector expression is simplified, but not the remaining arms; to
  7595 enable full simplification of case-expressions for datatype t, you may
  7596 remove t.weak_case_cong from the simpset, either globally (Delcongs
  7597 [thm"t.weak_case_cong"];) or locally (delcongs [...]).
  7598 
  7599 * HOL/recdef: the recursion equations generated by 'recdef' for
  7600 function 'f' are now called f.simps instead of f.rules; if all
  7601 termination conditions are proved automatically, these simplification
  7602 rules are added to the simpset, as in primrec; rules may be named
  7603 individually as well, resulting in a separate list of theorems for
  7604 each equation;
  7605 
  7606 * HOL/While is a new theory that provides a while-combinator. It
  7607 permits the definition of tail-recursive functions without the
  7608 provision of a termination measure. The latter is necessary once the
  7609 invariant proof rule for while is applied.
  7610 
  7611 * HOL: new (overloaded) notation for the set of elements below/above
  7612 some element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
  7613 
  7614 * HOL: theorems impI, allI, ballI bound as "strip";
  7615 
  7616 * HOL: new tactic induct_thm_tac: thm -> string -> int -> tactic
  7617 induct_tac th "x1 ... xn" expects th to have a conclusion of the form
  7618 P v1 ... vn and abbreviates res_inst_tac [("v1","x1"),...,("vn","xn")] th;
  7619 
  7620 * HOL/Real: "rabs" replaced by overloaded "abs" function;
  7621 
  7622 * HOL: theory Sexp now in HOL/Induct examples (it used to be part of
  7623 main HOL, but was unused);
  7624 
  7625 * HOL: fewer consts declared as global (e.g. have to refer to
  7626 "Lfp.lfp" instead of "lfp" internally; affects ML packages only);
  7627 
  7628 * HOL: tuned AST representation of nested pairs, avoiding bogus output
  7629 in case of overlap with user translations (e.g. judgements over
  7630 tuples); (note that the underlying logical represenation is still
  7631 bogus);
  7632 
  7633 
  7634 *** ZF ***
  7635 
  7636 * ZF: simplification automatically cancels common terms in arithmetic
  7637 expressions over nat and int;
  7638 
  7639 * ZF: new treatment of nat to minimize type-checking: all operators
  7640 coerce their operands to a natural number using the function natify,
  7641 making the algebraic laws unconditional;
  7642 
  7643 * ZF: as above, for int: operators coerce their operands to an integer
  7644 using the function intify;
  7645 
  7646 * ZF: the integer library now contains many of the usual laws for the
  7647 orderings, including $<=, and monotonicity laws for $+ and $*;
  7648 
  7649 * ZF: new example ZF/ex/NatSum to demonstrate integer arithmetic
  7650 simplification;
  7651 
  7652 * FOL and ZF: AddIffs now available, giving theorems of the form P<->Q
  7653 to the simplifier and classical reasoner simultaneously;
  7654 
  7655 
  7656 *** General ***
  7657 
  7658 * Provers: blast_tac now handles actual object-logic rules as
  7659 assumptions; note that auto_tac uses blast_tac internally as well;
  7660 
  7661 * Provers: new functions rulify/rulify_no_asm: thm -> thm for turning
  7662 outer -->/All/Ball into ==>/!!; qed_spec_mp now uses rulify_no_asm;
  7663 
  7664 * Provers: delrules now handles destruct rules as well (no longer need
  7665 explicit make_elim);
  7666 
  7667 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
  7668   [| inj ?f;          ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7669 use instead the strong form,
  7670   [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
  7671 in HOL, FOL and ZF the function cla_make_elim will create such rules
  7672 from destruct-rules;
  7673 
  7674 * Provers: Simplifier.easy_setup provides a fast path to basic
  7675 Simplifier setup for new object-logics;
  7676 
  7677 * Pure: AST translation rules no longer require constant head on LHS;
  7678 
  7679 * Pure: improved name spaces: ambiguous output is qualified; support
  7680 for hiding of names;
  7681 
  7682 * system: smart setup of canonical ML_HOME, ISABELLE_INTERFACE, and
  7683 XSYMBOL_HOME; no longer need to do manual configuration in most
  7684 situations;
  7685 
  7686 * system: compression of ML heaps images may now be controlled via -c
  7687 option of isabelle and isatool usedir (currently only observed by
  7688 Poly/ML);
  7689 
  7690 * system: isatool installfonts may handle X-Symbol fonts as well (very
  7691 useful for remote X11);
  7692 
  7693 * system: provide TAGS file for Isabelle sources;
  7694 
  7695 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
  7696 order;
  7697 
  7698 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
  7699 timing flag supersedes proof_timing and Toplevel.trace;
  7700 
  7701 * ML: new combinators |>> and |>>> for incremental transformations
  7702 with secondary results (e.g. certain theory extensions):
  7703 
  7704 * ML: PureThy.add_defs gets additional argument to indicate potential
  7705 overloading (usually false);
  7706 
  7707 * ML: PureThy.add_thms/add_axioms/add_defs now return theorems as
  7708 results;
  7709 
  7710 
  7711 
  7712 New in Isabelle99 (October 1999)
  7713 --------------------------------
  7714 
  7715 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  7716 
  7717 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
  7718 are no longer simplified.  (This allows the simplifier to unfold recursive
  7719 functional programs.)  To restore the old behaviour, declare
  7720 
  7721     Delcongs [if_weak_cong];
  7722 
  7723 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
  7724 complement;
  7725 
  7726 * HOL: the predicate "inj" is now defined by translation to "inj_on";
  7727 
  7728 * HOL/datatype: mutual_induct_tac no longer exists --
  7729   use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
  7730 
  7731 * HOL/typedef: fixed type inference for representing set; type
  7732 arguments now have to occur explicitly on the rhs as type constraints;
  7733 
  7734 * ZF: The con_defs part of an inductive definition may no longer refer
  7735 to constants declared in the same theory;
  7736 
  7737 * HOL, ZF: the function mk_cases, generated by the inductive
  7738 definition package, has lost an argument.  To simplify its result, it
  7739 uses the default simpset instead of a supplied list of theorems.
  7740 
  7741 * HOL/List: the constructors of type list are now Nil and Cons;
  7742 
  7743 * Simplifier: the type of the infix ML functions
  7744         setSSolver addSSolver setSolver addSolver
  7745 is now  simpset * solver -> simpset  where `solver' is a new abstract type
  7746 for packaging solvers. A solver is created via
  7747         mk_solver: string -> (thm list -> int -> tactic) -> solver
  7748 where the string argument is only a comment.
  7749 
  7750 
  7751 *** Proof tools ***
  7752 
  7753 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
  7754 decision procedure for linear arithmetic. Currently it is used for
  7755 types `nat', `int', and `real' in HOL (see below); it can, should and
  7756 will be instantiated for other types and logics as well.
  7757 
  7758 * The simplifier now accepts rewrite rules with flexible heads, eg
  7759      hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
  7760   They are applied like any rule with a non-pattern lhs, i.e. by first-order
  7761   matching.
  7762 
  7763 
  7764 *** General ***
  7765 
  7766 * New Isabelle/Isar subsystem provides an alternative to traditional
  7767 tactical theorem proving; together with the ProofGeneral/isar user
  7768 interface it offers an interactive environment for developing human
  7769 readable proof documents (Isar == Intelligible semi-automated
  7770 reasoning); for further information see isatool doc isar-ref,
  7771 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
  7772 
  7773 * improved and simplified presentation of theories: better HTML markup
  7774 (including colors), graph views in several sizes; isatool usedir now
  7775 provides a proper interface for user theories (via -P option); actual
  7776 document preparation based on (PDF)LaTeX is available as well (for
  7777 new-style theories only); see isatool doc system for more information;
  7778 
  7779 * native support for Proof General, both for classic Isabelle and
  7780 Isabelle/Isar;
  7781 
  7782 * ML function thm_deps visualizes dependencies of theorems and lemmas,
  7783 using the graph browser tool;
  7784 
  7785 * Isabelle manuals now also available as PDF;
  7786 
  7787 * theory loader rewritten from scratch (may not be fully
  7788 bug-compatible); old loadpath variable has been replaced by show_path,
  7789 add_path, del_path, reset_path functions; new operations such as
  7790 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
  7791 isatool doc ref);
  7792 
  7793 * improved isatool install: option -k creates KDE application icon,
  7794 option -p DIR installs standalone binaries;
  7795 
  7796 * added ML_PLATFORM setting (useful for cross-platform installations);
  7797 more robust handling of platform specific ML images for SML/NJ;
  7798 
  7799 * the settings environment is now statically scoped, i.e. it is never
  7800 created again in sub-processes invoked from isabelle, isatool, or
  7801 Isabelle;
  7802 
  7803 * path element specification '~~' refers to '$ISABELLE_HOME';
  7804 
  7805 * in locales, the "assumes" and "defines" parts may be omitted if
  7806 empty;
  7807 
  7808 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
  7809 long arrows);
  7810 
  7811 * new print_mode "HTML";
  7812 
  7813 * new flag show_tags controls display of tags of theorems (which are
  7814 basically just comments that may be attached by some tools);
  7815 
  7816 * Isamode 2.6 requires patch to accomodate change of Isabelle font
  7817 mode and goal output format:
  7818 
  7819 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
  7820 244c244
  7821 <       (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
  7822 ---
  7823 >       (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
  7824 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
  7825 181c181
  7826 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
  7827 ---
  7828 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
  7829 
  7830 * function bind_thms stores lists of theorems (cf. bind_thm);
  7831 
  7832 * new shorthand tactics ftac, eatac, datac, fatac;
  7833 
  7834 * qed (and friends) now accept "" as result name; in that case the
  7835 theorem is not stored, but proper checks and presentation of the
  7836 result still apply;
  7837 
  7838 * theorem database now also indexes constants "Trueprop", "all",
  7839 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
  7840 
  7841 
  7842 *** HOL ***
  7843 
  7844 ** HOL arithmetic **
  7845 
  7846 * There are now decision procedures for linear arithmetic over nat and
  7847 int:
  7848 
  7849 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
  7850 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
  7851 are treated as atomic; subformulae not involving type `nat' or `int'
  7852 are ignored; quantified subformulae are ignored unless they are
  7853 positive universal or negative existential. The tactic has to be
  7854 invoked by hand and can be a little bit slow. In particular, the
  7855 running time is exponential in the number of occurrences of `min' and
  7856 `max', and `-' on `nat'.
  7857 
  7858 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
  7859 (negated) (in)equalities among the premises and the conclusion into
  7860 account (i.e. no compound formulae) and does not know about `min' and
  7861 `max', and `-' on `nat'. It is fast and is used automatically by the
  7862 simplifier.
  7863 
  7864 NB: At the moment, these decision procedures do not cope with mixed
  7865 nat/int formulae where the two parts interact, such as `m < n ==>
  7866 int(m) < int(n)'.
  7867 
  7868 * HOL/Numeral provides a generic theory of numerals (encoded
  7869 efficiently as bit strings); setup for types nat/int/real is in place;
  7870 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
  7871 int, existing theories and proof scripts may require a few additional
  7872 type constraints;
  7873 
  7874 * integer division and remainder can now be performed on constant
  7875 arguments;
  7876 
  7877 * many properties of integer multiplication, division and remainder
  7878 are now available;
  7879 
  7880 * An interface to the Stanford Validity Checker (SVC) is available through the
  7881 tactic svc_tac.  Propositional tautologies and theorems of linear arithmetic
  7882 are proved automatically.  SVC must be installed separately, and its results
  7883 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
  7884 invocation of the underlying oracle).  For SVC see
  7885   http://verify.stanford.edu/SVC
  7886 
  7887 * IsaMakefile: the HOL-Real target now builds an actual image;
  7888 
  7889 
  7890 ** HOL misc **
  7891 
  7892 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
  7893 (in Isabelle/Isar) -- by Gertrud Bauer;
  7894 
  7895 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
  7896 analysis for assembly languages with subtypes;
  7897 
  7898 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
  7899 -- avoids syntactic ambiguities and treats state, transition, and
  7900 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
  7901 changed syntax and (many) tactics;
  7902 
  7903 * HOL/inductive: Now also handles more general introduction rules such
  7904   as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
  7905   theorems are now maintained within the theory (maintained via the
  7906   "mono" attribute);
  7907 
  7908 * HOL/datatype: Now also handles arbitrarily branching datatypes
  7909   (using function types) such as
  7910 
  7911   datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
  7912 
  7913 * HOL/record: record_simproc (part of the default simpset) takes care
  7914 of selectors applied to updated records; record_split_tac is no longer
  7915 part of the default claset; update_defs may now be removed from the
  7916 simpset in many cases; COMPATIBILITY: old behavior achieved by
  7917 
  7918   claset_ref () := claset() addSWrapper record_split_wrapper;
  7919   Delsimprocs [record_simproc]
  7920 
  7921 * HOL/typedef: fixed type inference for representing set; type
  7922 arguments now have to occur explicitly on the rhs as type constraints;
  7923 
  7924 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
  7925 names rather than an ML expression;
  7926 
  7927 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
  7928 supplied later.  Program schemes can be defined, such as
  7929     "While B C s = (if B s then While B C (C s) else s)"
  7930 where the well-founded relation can be chosen after B and C have been given.
  7931 
  7932 * HOL/List: the constructors of type list are now Nil and Cons;
  7933 INCOMPATIBILITY: while [] and infix # syntax is still there, of
  7934 course, ML tools referring to List.list.op # etc. have to be adapted;
  7935 
  7936 * HOL_quantifiers flag superseded by "HOL" print mode, which is
  7937 disabled by default; run isabelle with option -m HOL to get back to
  7938 the original Gordon/HOL-style output;
  7939 
  7940 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
  7941 ALL x<=y. P, EX x<y. P, EX x<=y. P;
  7942 
  7943 * HOL basic syntax simplified (more orthogonal): all variants of
  7944 All/Ex now support plain / symbolic / HOL notation; plain syntax for
  7945 Eps operator is provided as well: "SOME x. P[x]";
  7946 
  7947 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
  7948 
  7949 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
  7950 thus available for user theories;
  7951 
  7952 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
  7953 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
  7954 time;
  7955 
  7956 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
  7957 several times and then mp;
  7958 
  7959 
  7960 *** LK ***
  7961 
  7962 * the notation <<...>> is now available as a notation for sequences of
  7963 formulas;
  7964 
  7965 * the simplifier is now installed
  7966 
  7967 * the axiom system has been generalized (thanks to Soren Heilmann)
  7968 
  7969 * the classical reasoner now has a default rule database
  7970 
  7971 
  7972 *** ZF ***
  7973 
  7974 * new primrec section allows primitive recursive functions to be given
  7975 directly (as in HOL) over datatypes and the natural numbers;
  7976 
  7977 * new tactics induct_tac and exhaust_tac for induction (or case
  7978 analysis) over datatypes and the natural numbers;
  7979 
  7980 * the datatype declaration of type T now defines the recursor T_rec;
  7981 
  7982 * simplification automatically does freeness reasoning for datatype
  7983 constructors;
  7984 
  7985 * automatic type-inference, with AddTCs command to insert new
  7986 type-checking rules;
  7987 
  7988 * datatype introduction rules are now added as Safe Introduction rules
  7989 to the claset;
  7990 
  7991 * the syntax "if P then x else y" is now available in addition to
  7992 if(P,x,y);
  7993 
  7994 
  7995 *** Internal programming interfaces ***
  7996 
  7997 * tuned simplifier trace output; new flag debug_simp;
  7998 
  7999 * structures Vartab / Termtab (instances of TableFun) offer efficient
  8000 tables indexed by indexname_ord / term_ord (compatible with aconv);
  8001 
  8002 * AxClass.axclass_tac lost the theory argument;
  8003 
  8004 * tuned current_goals_markers semantics: begin / end goal avoids
  8005 printing empty lines;
  8006 
  8007 * removed prs and prs_fn hook, which was broken because it did not
  8008 include \n in its semantics, forcing writeln to add one
  8009 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
  8010 string -> unit if you really want to output text without newline;
  8011 
  8012 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
  8013 plain output, interface builders may have to enable 'isabelle_font'
  8014 mode to get Isabelle font glyphs as before;
  8015 
  8016 * refined token_translation interface; INCOMPATIBILITY: output length
  8017 now of type real instead of int;
  8018 
  8019 * theory loader actions may be traced via new ThyInfo.add_hook
  8020 interface (see src/Pure/Thy/thy_info.ML); example application: keep
  8021 your own database of information attached to *whole* theories -- as
  8022 opposed to intra-theory data slots offered via TheoryDataFun;
  8023 
  8024 * proper handling of dangling sort hypotheses (at last!);
  8025 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
  8026 extra sort hypotheses that can be witnessed from the type signature;
  8027 the force_strip_shyps flag is gone, any remaining shyps are simply
  8028 left in the theorem (with a warning issued by strip_shyps_warning);
  8029 
  8030 
  8031 
  8032 New in Isabelle98-1 (October 1998)
  8033 ----------------------------------
  8034 
  8035 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8036 
  8037 * several changes of automated proof tools;
  8038 
  8039 * HOL: major changes to the inductive and datatype packages, including
  8040 some minor incompatibilities of theory syntax;
  8041 
  8042 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
  8043 called `inj_on';
  8044 
  8045 * HOL: removed duplicate thms in Arith:
  8046   less_imp_add_less  should be replaced by  trans_less_add1
  8047   le_imp_add_le      should be replaced by  trans_le_add1
  8048 
  8049 * HOL: unary minus is now overloaded (new type constraints may be
  8050 required);
  8051 
  8052 * HOL and ZF: unary minus for integers is now #- instead of #~.  In
  8053 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
  8054 now taken as an integer constant.
  8055 
  8056 * Pure: ML function 'theory_of' renamed to 'theory';
  8057 
  8058 
  8059 *** Proof tools ***
  8060 
  8061 * Simplifier:
  8062   1. Asm_full_simp_tac is now more aggressive.
  8063      1. It will sometimes reorient premises if that increases their power to
  8064         simplify.
  8065      2. It does no longer proceed strictly from left to right but may also
  8066         rotate premises to achieve further simplification.
  8067      For compatibility reasons there is now Asm_lr_simp_tac which is like the
  8068      old Asm_full_simp_tac in that it does not rotate premises.
  8069   2. The simplifier now knows a little bit about nat-arithmetic.
  8070 
  8071 * Classical reasoner: wrapper mechanism for the classical reasoner now
  8072 allows for selected deletion of wrappers, by introduction of names for
  8073 wrapper functionals.  This implies that addbefore, addSbefore,
  8074 addaltern, and addSaltern now take a pair (name, tactic) as argument,
  8075 and that adding two tactics with the same name overwrites the first
  8076 one (emitting a warning).
  8077   type wrapper = (int -> tactic) -> (int -> tactic)
  8078   setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
  8079   addWrapper, addSWrapper: claset * (string * wrapper) -> claset
  8080   delWrapper, delSWrapper: claset *  string            -> claset
  8081   getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
  8082 
  8083 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
  8084 semantics; addbefore now affects only the unsafe part of step_tac
  8085 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
  8086 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
  8087 by Force_tac;
  8088 
  8089 * Classical reasoner: setwrapper to setWrapper and compwrapper to
  8090 compWrapper; added safe wrapper (and access functions for it);
  8091 
  8092 * HOL/split_all_tac is now much faster and fails if there is nothing
  8093 to split.  Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
  8094 and the names of the automatically generated variables have changed.
  8095 split_all_tac has moved within claset() from unsafe wrappers to safe
  8096 wrappers, which means that !!-bound variables are split much more
  8097 aggressively, and safe_tac and clarify_tac now split such variables.
  8098 If this splitting is not appropriate, use delSWrapper "split_all_tac".
  8099 Note: the same holds for record_split_tac, which does the job of
  8100 split_all_tac for record fields.
  8101 
  8102 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
  8103 permanently to the default simpset using Addsplits just like
  8104 Addsimps. They can be removed via Delsplits just like
  8105 Delsimps. Lower-case versions are also available.
  8106 
  8107 * HOL/Simplifier: The rule split_if is now part of the default
  8108 simpset. This means that the simplifier will eliminate all occurrences
  8109 of if-then-else in the conclusion of a goal. To prevent this, you can
  8110 either remove split_if completely from the default simpset by
  8111 `Delsplits [split_if]' or remove it in a specific call of the
  8112 simplifier using `... delsplits [split_if]'.  You can also add/delete
  8113 other case splitting rules to/from the default simpset: every datatype
  8114 generates suitable rules `split_t_case' and `split_t_case_asm' (where
  8115 t is the name of the datatype).
  8116 
  8117 * Classical reasoner / Simplifier combination: new force_tac (and
  8118 derivatives Force_tac, force) combines rewriting and classical
  8119 reasoning (and whatever other tools) similarly to auto_tac, but is
  8120 aimed to solve the given subgoal completely.
  8121 
  8122 
  8123 *** General ***
  8124 
  8125 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
  8126 and `goalw': the theory is no longer needed as an explicit argument -
  8127 the current theory context is used; assumptions are no longer returned
  8128 at the ML-level unless one of them starts with ==> or !!; it is
  8129 recommended to convert to these new commands using isatool fixgoal
  8130 (backup your sources first!);
  8131 
  8132 * new top-level commands 'thm' and 'thms' for retrieving theorems from
  8133 the current theory context, and 'theory' to lookup stored theories;
  8134 
  8135 * new theory section 'locale' for declaring constants, assumptions and
  8136 definitions that have local scope;
  8137 
  8138 * new theory section 'nonterminals' for purely syntactic types;
  8139 
  8140 * new theory section 'setup' for generic ML setup functions
  8141 (e.g. package initialization);
  8142 
  8143 * the distribution now includes Isabelle icons: see
  8144 lib/logo/isabelle-{small,tiny}.xpm;
  8145 
  8146 * isatool install - install binaries with absolute references to
  8147 ISABELLE_HOME/bin;
  8148 
  8149 * isatool logo -- create instances of the Isabelle logo (as EPS);
  8150 
  8151 * print mode 'emacs' reserved for Isamode;
  8152 
  8153 * support multiple print (ast) translations per constant name;
  8154 
  8155 * theorems involving oracles are now printed with a suffixed [!];
  8156 
  8157 
  8158 *** HOL ***
  8159 
  8160 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
  8161 
  8162 * HOL/inductive package reorganized and improved: now supports mutual
  8163 definitions such as
  8164 
  8165   inductive EVEN ODD
  8166     intrs
  8167       null "0 : EVEN"
  8168       oddI "n : EVEN ==> Suc n : ODD"
  8169       evenI "n : ODD ==> Suc n : EVEN"
  8170 
  8171 new theorem list "elims" contains an elimination rule for each of the
  8172 recursive sets; inductive definitions now handle disjunctive premises
  8173 correctly (also ZF);
  8174 
  8175 INCOMPATIBILITIES: requires Inductive as an ancestor; component
  8176 "mutual_induct" no longer exists - the induction rule is always
  8177 contained in "induct";
  8178 
  8179 
  8180 * HOL/datatype package re-implemented and greatly improved: now
  8181 supports mutually recursive datatypes such as
  8182 
  8183   datatype
  8184     'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
  8185             | SUM ('a aexp) ('a aexp)
  8186             | DIFF ('a aexp) ('a aexp)
  8187             | NUM 'a
  8188   and
  8189     'a bexp = LESS ('a aexp) ('a aexp)
  8190             | AND ('a bexp) ('a bexp)
  8191             | OR ('a bexp) ('a bexp)
  8192 
  8193 as well as indirectly recursive datatypes such as
  8194 
  8195   datatype
  8196     ('a, 'b) term = Var 'a
  8197                   | App 'b ((('a, 'b) term) list)
  8198 
  8199 The new tactic  mutual_induct_tac [<var_1>, ..., <var_n>] i  performs
  8200 induction on mutually / indirectly recursive datatypes.
  8201 
  8202 Primrec equations are now stored in theory and can be accessed via
  8203 <function_name>.simps.
  8204 
  8205 INCOMPATIBILITIES:
  8206 
  8207   - Theories using datatypes must now have theory Datatype as an
  8208     ancestor.
  8209   - The specific <typename>.induct_tac no longer exists - use the
  8210     generic induct_tac instead.
  8211   - natE has been renamed to nat.exhaust - use exhaust_tac
  8212     instead of res_inst_tac ... natE. Note that the variable
  8213     names in nat.exhaust differ from the names in natE, this
  8214     may cause some "fragile" proofs to fail.
  8215   - The theorems split_<typename>_case and split_<typename>_case_asm
  8216     have been renamed to <typename>.split and <typename>.split_asm.
  8217   - Since default sorts of type variables are now handled correctly,
  8218     some datatype definitions may have to be annotated with explicit
  8219     sort constraints.
  8220   - Primrec definitions no longer require function name and type
  8221     of recursive argument.
  8222 
  8223 Consider using isatool fixdatatype to adapt your theories and proof
  8224 scripts to the new package (backup your sources first!).
  8225 
  8226 
  8227 * HOL/record package: considerably improved implementation; now
  8228 includes concrete syntax for record types, terms, updates; theorems
  8229 for surjective pairing and splitting !!-bound record variables; proof
  8230 support is as follows:
  8231 
  8232   1) standard conversions (selectors or updates applied to record
  8233 constructor terms) are part of the standard simpset;
  8234 
  8235   2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
  8236 made part of standard simpset and claset via addIffs;
  8237 
  8238   3) a tactic for record field splitting (record_split_tac) is part of
  8239 the standard claset (addSWrapper);
  8240 
  8241 To get a better idea about these rules you may retrieve them via
  8242 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
  8243 the name of your record type.
  8244 
  8245 The split tactic 3) conceptually simplifies by the following rule:
  8246 
  8247   "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
  8248 
  8249 Thus any record variable that is bound by meta-all will automatically
  8250 blow up into some record constructor term, consequently the
  8251 simplifications of 1), 2) apply.  Thus force_tac, auto_tac etc. shall
  8252 solve record problems automatically.
  8253 
  8254 
  8255 * reorganized the main HOL image: HOL/Integ and String loaded by
  8256 default; theory Main includes everything;
  8257 
  8258 * automatic simplification of integer sums and comparisons, using cancellation;
  8259 
  8260 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
  8261 
  8262 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
  8263 
  8264 * many new identities for unions, intersections, set difference, etc.;
  8265 
  8266 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
  8267 called split_if, split_split, split_sum_case and split_nat_case (to go
  8268 with add/delsplits);
  8269 
  8270 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
  8271 (?x::unit) = (); this is made part of the default simpset, which COULD
  8272 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
  8273 'Delsimprocs [unit_eq_proc];' as last resort); also note that
  8274 unit_abs_eta_conv is added in order to counter the effect of
  8275 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
  8276 %u.f();
  8277 
  8278 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
  8279 makes more sense);
  8280 
  8281 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8282   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8283   disjointness reasoning but breaking a few old proofs.
  8284 
  8285 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
  8286 to 'converse' from 'inverse' (for compatibility with ZF and some
  8287 literature);
  8288 
  8289 * HOL/recdef can now declare non-recursive functions, with {} supplied as
  8290 the well-founded relation;
  8291 
  8292 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
  8293     Compl A.  The "Compl" syntax remains available as input syntax for this
  8294     release ONLY.
  8295 
  8296 * HOL/Update: new theory of function updates:
  8297     f(a:=b) == %x. if x=a then b else f x
  8298 may also be iterated as in f(a:=b,c:=d,...);
  8299 
  8300 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
  8301 
  8302 * HOL/List:
  8303   - new function list_update written xs[i:=v] that updates the i-th
  8304     list position. May also be iterated as in xs[i:=a,j:=b,...].
  8305   - new function `upt' written [i..j(] which generates the list
  8306     [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
  8307     bound write [i..j], which is a shorthand for [i..j+1(].
  8308   - new lexicographic orderings and corresponding wellfoundedness theorems.
  8309 
  8310 * HOL/Arith:
  8311   - removed 'pred' (predecessor) function;
  8312   - generalized some theorems about n-1;
  8313   - many new laws about "div" and "mod";
  8314   - new laws about greatest common divisors (see theory ex/Primes);
  8315 
  8316 * HOL/Relation: renamed the relational operator r^-1 "converse"
  8317 instead of "inverse";
  8318 
  8319 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
  8320   of the multiset ordering;
  8321 
  8322 * directory HOL/Real: a construction of the reals using Dedekind cuts
  8323   (not included by default);
  8324 
  8325 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
  8326 
  8327 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
  8328   programs, i.e. different program variables may have different types.
  8329 
  8330 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8331   [previously, this check worked only if the rewrite rule was unconditional]
  8332   Now rew can involve either definitions or equalities (either == or =).
  8333 
  8334 
  8335 *** ZF ***
  8336 
  8337 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
  8338   only the theorems proved on ZF.ML;
  8339 
  8340 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
  8341   It and 'sym RS equals0D' are now in the default  claset, giving automatic
  8342   disjointness reasoning but breaking a few old proofs.
  8343 
  8344 * ZF/Update: new theory of function updates
  8345     with default rewrite rule  f(x:=y) ` z = if(z=x, y, f`z)
  8346   may also be iterated as in f(a:=b,c:=d,...);
  8347 
  8348 * in  let x=t in u(x), neither t nor u(x) has to be an FOL term.
  8349 
  8350 * calling (stac rew i) now fails if "rew" has no effect on the goal
  8351   [previously, this check worked only if the rewrite rule was unconditional]
  8352   Now rew can involve either definitions or equalities (either == or =).
  8353 
  8354 * case_tac provided for compatibility with HOL
  8355     (like the old excluded_middle_tac, but with subgoals swapped)
  8356 
  8357 
  8358 *** Internal programming interfaces ***
  8359 
  8360 * Pure: several new basic modules made available for general use, see
  8361 also src/Pure/README;
  8362 
  8363 * improved the theory data mechanism to support encapsulation (data
  8364 kind name replaced by private Object.kind, acting as authorization
  8365 key); new type-safe user interface via functor TheoryDataFun; generic
  8366 print_data function becomes basically useless;
  8367 
  8368 * removed global_names compatibility flag -- all theory declarations
  8369 are qualified by default;
  8370 
  8371 * module Pure/Syntax now offers quote / antiquote translation
  8372 functions (useful for Hoare logic etc. with implicit dependencies);
  8373 see HOL/ex/Antiquote for an example use;
  8374 
  8375 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
  8376 cterm -> thm;
  8377 
  8378 * new tactical CHANGED_GOAL for checking that a tactic modifies a
  8379 subgoal;
  8380 
  8381 * Display.print_goals function moved to Locale.print_goals;
  8382 
  8383 * standard print function for goals supports current_goals_markers
  8384 variable for marking begin of proof, end of proof, start of goal; the
  8385 default is ("", "", ""); setting current_goals_markers := ("<proof>",
  8386 "</proof>", "<goal>") causes SGML like tagged proof state printing,
  8387 for example;
  8388 
  8389 
  8390 
  8391 New in Isabelle98 (January 1998)
  8392 --------------------------------
  8393 
  8394 *** Overview of INCOMPATIBILITIES (see below for more details) ***
  8395 
  8396 * changed lexical syntax of terms / types: dots made part of long
  8397 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
  8398 
  8399 * simpset (and claset) reference variable replaced by functions
  8400 simpset / simpset_ref;
  8401 
  8402 * no longer supports theory aliases (via merge) and non-trivial
  8403 implicit merge of thms' signatures;
  8404 
  8405 * most internal names of constants changed due to qualified names;
  8406 
  8407 * changed Pure/Sequence interface (see Pure/seq.ML);
  8408 
  8409 
  8410 *** General Changes ***
  8411 
  8412 * hierachically structured name spaces (for consts, types, axms, thms
  8413 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
  8414 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
  8415 isatool fixdots ensures space after dots (e.g. "%x. x"); set
  8416 long_names for fully qualified output names; NOTE: ML programs
  8417 (special tactics, packages etc.) referring to internal names may have
  8418 to be adapted to cope with fully qualified names; in case of severe
  8419 backward campatibility problems try setting 'global_names' at compile
  8420 time to have enrything declared within a flat name space; one may also
  8421 fine tune name declarations in theories via the 'global' and 'local'
  8422 section;
  8423 
  8424 * reimplemented the implicit simpset and claset using the new anytype
  8425 data filed in signatures; references simpset:simpset ref etc. are
  8426 replaced by functions simpset:unit->simpset and
  8427 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
  8428 to patch your ML files accordingly;
  8429 
  8430 * HTML output now includes theory graph data for display with Java
  8431 applet or isatool browser; data generated automatically via isatool
  8432 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
  8433 
  8434 * defs may now be conditional; improved rewrite_goals_tac to handle
  8435 conditional equations;
  8436 
  8437 * defs now admits additional type arguments, using TYPE('a) syntax;
  8438 
  8439 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
  8440 creates a new theory node; implicit merge of thms' signatures is
  8441 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
  8442 transfer:theory->thm->thm in (rare) cases;
  8443 
  8444 * improved handling of draft signatures / theories; draft thms (and
  8445 ctyps, cterms) are automatically promoted to real ones;
  8446 
  8447 * slightly changed interfaces for oracles: admit many per theory, named
  8448 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
  8449 
  8450 * print_goals: optional output of const types (set show_consts and
  8451 show_types);
  8452 
  8453 * improved output of warnings (###) and errors (***);
  8454 
  8455 * subgoal_tac displays a warning if the new subgoal has type variables;
  8456 
  8457 * removed old README and Makefiles;
  8458 
  8459 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
  8460 
  8461 * removed obsolete init_pps and init_database;
  8462 
  8463 * deleted the obsolete tactical STATE, which was declared by
  8464     fun STATE tacfun st = tacfun st st;
  8465 
  8466 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
  8467 (which abbreviates $HOME);
  8468 
  8469 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
  8470 use isatool fixseq to adapt your ML programs (this works for fully
  8471 qualified references to the Sequence structure only!);
  8472 
  8473 * use_thy no longer requires writable current directory; it always
  8474 reloads .ML *and* .thy file, if either one is out of date;
  8475 
  8476 
  8477 *** Classical Reasoner ***
  8478 
  8479 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
  8480 tactics that use classical reasoning to simplify a subgoal without
  8481 splitting it into several subgoals;
  8482 
  8483 * Safe_tac: like safe_tac but uses the default claset;
  8484 
  8485 
  8486 *** Simplifier ***
  8487 
  8488 * added simplification meta rules:
  8489     (asm_)(full_)simplify: simpset -> thm -> thm;
  8490 
  8491 * simplifier.ML no longer part of Pure -- has to be loaded by object
  8492 logics (again);
  8493 
  8494 * added prems argument to simplification procedures;
  8495 
  8496 * HOL, FOL, ZF: added infix function `addsplits':
  8497   instead of `<simpset> setloop (split_tac <thms>)'
  8498   you can simply write `<simpset> addsplits <thms>'
  8499 
  8500 
  8501 *** Syntax ***
  8502 
  8503 * TYPE('a) syntax for type reflection terms;
  8504 
  8505 * no longer handles consts with name "" -- declare as 'syntax' instead;
  8506 
  8507 * pretty printer: changed order of mixfix annotation preference (again!);
  8508 
  8509 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
  8510 
  8511 
  8512 *** HOL ***
  8513 
  8514 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8515   with `addloop' of the simplifier to faciliate case splitting in premises.
  8516 
  8517 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
  8518 
  8519 * HOL/Auth: new protocol proofs including some for the Internet
  8520   protocol TLS;
  8521 
  8522 * HOL/Map: new theory of `maps' a la VDM;
  8523 
  8524 * HOL/simplifier: simplification procedures nat_cancel_sums for
  8525 cancelling out common nat summands from =, <, <= (in)equalities, or
  8526 differences; simplification procedures nat_cancel_factor for
  8527 cancelling common factor from =, <, <= (in)equalities over natural
  8528 sums; nat_cancel contains both kinds of procedures, it is installed by
  8529 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
  8530 
  8531 * HOL/simplifier: terms of the form
  8532   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
  8533   are rewritten to
  8534   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
  8535   and those of the form
  8536   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
  8537   are rewritten to
  8538   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
  8539 
  8540 * HOL/datatype
  8541   Each datatype `t' now comes with a theorem `split_t_case' of the form
  8542 
  8543   P(t_case f1 ... fn x) =
  8544      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
  8545         ...
  8546        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
  8547      )
  8548 
  8549   and a theorem `split_t_case_asm' of the form
  8550 
  8551   P(t_case f1 ... fn x) =
  8552     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
  8553         ...
  8554        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
  8555      )
  8556   which can be added to a simpset via `addsplits'. The existing theorems
  8557   expand_list_case and expand_option_case have been renamed to
  8558   split_list_case and split_option_case.
  8559 
  8560 * HOL/Arithmetic:
  8561   - `pred n' is automatically converted to `n-1'.
  8562     Users are strongly encouraged not to use `pred' any longer,
  8563     because it will disappear altogether at some point.
  8564   - Users are strongly encouraged to write "0 < n" rather than
  8565     "n ~= 0". Theorems and proof tools have been modified towards this
  8566     `standard'.
  8567 
  8568 * HOL/Lists:
  8569   the function "set_of_list" has been renamed "set" (and its theorems too);
  8570   the function "nth" now takes its arguments in the reverse order and
  8571   has acquired the infix notation "!" as in "xs!n".
  8572 
  8573 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
  8574 
  8575 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
  8576   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
  8577 
  8578 * HOL/record: extensible records with schematic structural subtyping
  8579 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
  8580 still lacks various theorems and concrete record syntax;
  8581 
  8582 
  8583 *** HOLCF ***
  8584 
  8585 * removed "axioms" and "generated by" sections;
  8586 
  8587 * replaced "ops" section by extended "consts" section, which is capable of
  8588   handling the continuous function space "->" directly;
  8589 
  8590 * domain package:
  8591   . proves theorems immediately and stores them in the theory,
  8592   . creates hierachical name space,
  8593   . now uses normal mixfix annotations (instead of cinfix...),
  8594   . minor changes to some names and values (for consistency),
  8595   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
  8596   . separator between mutual domain defs: changed "," to "and",
  8597   . improved handling of sort constraints;  now they have to
  8598     appear on the left-hand side of the equations only;
  8599 
  8600 * fixed LAM <x,y,zs>.b syntax;
  8601 
  8602 * added extended adm_tac to simplifier in HOLCF -- can now discharge
  8603 adm (%x. P (t x)), where P is chainfinite and t continuous;
  8604 
  8605 
  8606 *** FOL and ZF ***
  8607 
  8608 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
  8609   with `addloop' of the simplifier to faciliate case splitting in premises.
  8610 
  8611 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
  8612 in HOL, they strip ALL and --> from proved theorems;
  8613 
  8614 
  8615 
  8616 New in Isabelle94-8 (May 1997)
  8617 ------------------------------
  8618 
  8619 *** General Changes ***
  8620 
  8621 * new utilities to build / run / maintain Isabelle etc. (in parts
  8622 still somewhat experimental); old Makefiles etc. still functional;
  8623 
  8624 * new 'Isabelle System Manual';
  8625 
  8626 * INSTALL text, together with ./configure and ./build scripts;
  8627 
  8628 * reimplemented type inference for greater efficiency, better error
  8629 messages and clean internal interface;
  8630 
  8631 * prlim command for dealing with lots of subgoals (an easier way of
  8632 setting goals_limit);
  8633 
  8634 
  8635 *** Syntax ***
  8636 
  8637 * supports alternative (named) syntax tables (parser and pretty
  8638 printer); internal interface is provided by add_modesyntax(_i);
  8639 
  8640 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
  8641 be used in conjunction with the Isabelle symbol font; uses the
  8642 "symbols" syntax table;
  8643 
  8644 * added token_translation interface (may translate name tokens in
  8645 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
  8646 the current print_mode); IMPORTANT: user print translation functions
  8647 are responsible for marking newly introduced bounds
  8648 (Syntax.mark_boundT);
  8649 
  8650 * token translations for modes "xterm" and "xterm_color" that display
  8651 names in bold, underline etc. or colors (which requires a color
  8652 version of xterm);
  8653 
  8654 * infixes may now be declared with names independent of their syntax;
  8655 
  8656 * added typed_print_translation (like print_translation, but may
  8657 access type of constant);
  8658 
  8659 
  8660 *** Classical Reasoner ***
  8661 
  8662 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
  8663 some limitations.  Blast_tac...
  8664   + ignores addss, addbefore, addafter; this restriction is intrinsic
  8665   + ignores elimination rules that don't have the correct format
  8666         (the conclusion MUST be a formula variable)
  8667   + ignores types, which can make HOL proofs fail
  8668   + rules must not require higher-order unification, e.g. apply_type in ZF
  8669     [message "Function Var's argument not a bound variable" relates to this]
  8670   + its proof strategy is more general but can actually be slower
  8671 
  8672 * substitution with equality assumptions no longer permutes other
  8673 assumptions;
  8674 
  8675 * minor changes in semantics of addafter (now called addaltern); renamed
  8676 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
  8677 (and access functions for it);
  8678 
  8679 * improved combination of classical reasoner and simplifier:
  8680   + functions for handling clasimpsets
  8681   + improvement of addss: now the simplifier is called _after_ the
  8682     safe steps.
  8683   + safe variant of addss called addSss: uses safe simplifications
  8684     _during_ the safe steps. It is more complete as it allows multiple
  8685     instantiations of unknowns (e.g. with slow_tac).
  8686 
  8687 *** Simplifier ***
  8688 
  8689 * added interface for simplification procedures (functions that
  8690 produce *proven* rewrite rules on the fly, depending on current
  8691 redex);
  8692 
  8693 * ordering on terms as parameter (used for ordered rewriting);
  8694 
  8695 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
  8696 
  8697 * the solver is now split into a safe and an unsafe part.
  8698 This should be invisible for the normal user, except that the
  8699 functions setsolver and addsolver have been renamed to setSolver and
  8700 addSolver; added safe_asm_full_simp_tac;
  8701 
  8702 
  8703 *** HOL ***
  8704 
  8705 * a generic induction tactic `induct_tac' which works for all datatypes and
  8706 also for type `nat';
  8707 
  8708 * a generic case distinction tactic `exhaust_tac' which works for all
  8709 datatypes and also for type `nat';
  8710 
  8711 * each datatype comes with a function `size';
  8712 
  8713 * patterns in case expressions allow tuple patterns as arguments to
  8714 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
  8715 
  8716 * primrec now also works with type nat;
  8717 
  8718 * recdef: a new declaration form, allows general recursive functions to be
  8719 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
  8720 
  8721 * the constant for negation has been renamed from "not" to "Not" to
  8722 harmonize with FOL, ZF, LK, etc.;
  8723 
  8724 * HOL/ex/LFilter theory of a corecursive "filter" functional for
  8725 infinite lists;
  8726 
  8727 * HOL/Modelcheck demonstrates invocation of model checker oracle;
  8728 
  8729 * HOL/ex/Ring.thy declares cring_simp, which solves equational
  8730 problems in commutative rings, using axiomatic type classes for + and *;
  8731 
  8732 * more examples in HOL/MiniML and HOL/Auth;
  8733 
  8734 * more default rewrite rules for quantifiers, union/intersection;
  8735 
  8736 * a new constant `arbitrary == @x.False';
  8737 
  8738 * HOLCF/IOA replaces old HOL/IOA;
  8739 
  8740 * HOLCF changes: derived all rules and arities
  8741   + axiomatic type classes instead of classes
  8742   + typedef instead of faking type definitions
  8743   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
  8744   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
  8745   + eliminated the types void, one, tr
  8746   + use unit lift and bool lift (with translations) instead of one and tr
  8747   + eliminated blift from Lift3.thy (use Def instead of blift)
  8748   all eliminated rules are derived as theorems --> no visible changes ;
  8749 
  8750 
  8751 *** ZF ***
  8752 
  8753 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
  8754 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
  8755 as ZF_cs addSIs [equalityI];
  8756 
  8757 
  8758 
  8759 New in Isabelle94-7 (November 96)
  8760 ---------------------------------
  8761 
  8762 * allowing negative levels (as offsets) in prlev and choplev;
  8763 
  8764 * super-linear speedup for large simplifications;
  8765 
  8766 * FOL, ZF and HOL now use miniscoping: rewriting pushes
  8767 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
  8768 FAIL); can suppress it using the command Delsimps (ex_simps @
  8769 all_simps); De Morgan laws are also now included, by default;
  8770 
  8771 * improved printing of ==>  :  ~:
  8772 
  8773 * new object-logic "Sequents" adds linear logic, while replacing LK
  8774 and Modal (thanks to Sara Kalvala);
  8775 
  8776 * HOL/Auth: correctness proofs for authentication protocols;
  8777 
  8778 * HOL: new auto_tac combines rewriting and classical reasoning (many
  8779 examples on HOL/Auth);
  8780 
  8781 * HOL: new command AddIffs for declaring theorems of the form P=Q to
  8782 the rewriter and classical reasoner simultaneously;
  8783 
  8784 * function uresult no longer returns theorems in "standard" format;
  8785 regain previous version by: val uresult = standard o uresult;
  8786 
  8787 
  8788 
  8789 New in Isabelle94-6
  8790 -------------------
  8791 
  8792 * oracles -- these establish an interface between Isabelle and trusted
  8793 external reasoners, which may deliver results as theorems;
  8794 
  8795 * proof objects (in particular record all uses of oracles);
  8796 
  8797 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
  8798 
  8799 * "constdefs" section in theory files;
  8800 
  8801 * "primrec" section (HOL) no longer requires names;
  8802 
  8803 * internal type "tactic" now simply "thm -> thm Sequence.seq";
  8804 
  8805 
  8806 
  8807 New in Isabelle94-5
  8808 -------------------
  8809 
  8810 * reduced space requirements;
  8811 
  8812 * automatic HTML generation from theories;
  8813 
  8814 * theory files no longer require "..." (quotes) around most types;
  8815 
  8816 * new examples, including two proofs of the Church-Rosser theorem;
  8817 
  8818 * non-curried (1994) version of HOL is no longer distributed;
  8819 
  8820 
  8821 
  8822 New in Isabelle94-4
  8823 -------------------
  8824 
  8825 * greatly reduced space requirements;
  8826 
  8827 * theory files (.thy) no longer require \...\ escapes at line breaks;
  8828 
  8829 * searchable theorem database (see the section "Retrieving theorems" on
  8830 page 8 of the Reference Manual);
  8831 
  8832 * new examples, including Grabczewski's monumental case study of the
  8833 Axiom of Choice;
  8834 
  8835 * The previous version of HOL renamed to Old_HOL;
  8836 
  8837 * The new version of HOL (previously called CHOL) uses a curried syntax
  8838 for functions.  Application looks like f a b instead of f(a,b);
  8839 
  8840 * Mutually recursive inductive definitions finally work in HOL;
  8841 
  8842 * In ZF, pattern-matching on tuples is now available in all abstractions and
  8843 translates to the operator "split";
  8844 
  8845 
  8846 
  8847 New in Isabelle94-3
  8848 -------------------
  8849 
  8850 * new infix operator, addss, allowing the classical reasoner to
  8851 perform simplification at each step of its search.  Example:
  8852         fast_tac (cs addss ss)
  8853 
  8854 * a new logic, CHOL, the same as HOL, but with a curried syntax
  8855 for functions.  Application looks like f a b instead of f(a,b).  Also pairs
  8856 look like (a,b) instead of <a,b>;
  8857 
  8858 * PLEASE NOTE: CHOL will eventually replace HOL!
  8859 
  8860 * In CHOL, pattern-matching on tuples is now available in all abstractions.
  8861 It translates to the operator "split".  A new theory of integers is available;
  8862 
  8863 * In ZF, integer numerals now denote two's-complement binary integers.
  8864 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
  8865 
  8866 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
  8867 of the Axiom of Choice;
  8868 
  8869 
  8870 
  8871 New in Isabelle94-2
  8872 -------------------
  8873 
  8874 * Significantly faster resolution;
  8875 
  8876 * the different sections in a .thy file can now be mixed and repeated
  8877 freely;
  8878 
  8879 * Database of theorems for FOL, HOL and ZF.  New
  8880 commands including qed, qed_goal and bind_thm store theorems in the database.
  8881 
  8882 * Simple database queries: return a named theorem (get_thm) or all theorems of
  8883 a given theory (thms_of), or find out what theory a theorem was proved in
  8884 (theory_of_thm);
  8885 
  8886 * Bugs fixed in the inductive definition and datatype packages;
  8887 
  8888 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
  8889 and HOL_dup_cs obsolete;
  8890 
  8891 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
  8892 have been removed;
  8893 
  8894 * Simpler definition of function space in ZF;
  8895 
  8896 * new results about cardinal and ordinal arithmetic in ZF;
  8897 
  8898 * 'subtype' facility in HOL for introducing new types as subsets of existing
  8899 types;
  8900 
  8901 :mode=text:wrap=hard:maxLineLen=72: