NEWS
author bulwahn
Tue Dec 20 17:40:18 2011 +0100 (2011-12-20)
changeset 45928 874845660119
parent 45874 ab10ce781e34
child 45941 2fd0bbf8be13
permissions -rw-r--r--
adding quickcheck generators in some HOL-Library theories
     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 * Theory HOL/Library/AList has been renamed to AList_Impl. INCOMPABILITY.
    57 
    58 * 'datatype' specifications allow explicit sort constraints.
    59 
    60 * Theory HOL/Library/Diagonalize has been removed. INCOMPATIBILITY, use
    61 theory HOL/Library/Nat_Bijection instead.
    62 
    63 * Session HOL-Word: Discontinued many redundant theorems specific to type
    64 'a word. INCOMPATIBILITY, use the corresponding generic theorems instead.
    65 
    66   word_sub_alt ~> word_sub_wi
    67   word_add_alt ~> word_add_def
    68   word_mult_alt ~> word_mult_def
    69   word_minus_alt ~> word_minus_def
    70   word_0_alt ~> word_0_wi
    71   word_1_alt ~> word_1_wi
    72   word_add_0 ~> add_0_left
    73   word_add_0_right ~> add_0_right
    74   word_mult_1 ~> mult_1_left
    75   word_mult_1_right ~> mult_1_right
    76   word_add_commute ~> add_commute
    77   word_add_assoc ~> add_assoc
    78   word_add_left_commute ~> add_left_commute
    79   word_mult_commute ~> mult_commute
    80   word_mult_assoc ~> mult_assoc
    81   word_mult_left_commute ~> mult_left_commute
    82   word_left_distrib ~> left_distrib
    83   word_right_distrib ~> right_distrib
    84   word_left_minus ~> left_minus
    85   word_diff_0_right ~> diff_0_right
    86   word_diff_self ~> diff_self
    87   word_diff_minus ~> diff_minus
    88   word_add_ac ~> add_ac
    89   word_mult_ac ~> mult_ac
    90   word_plus_ac0 ~> add_0_left add_0_right add_ac
    91   word_times_ac1 ~> mult_1_left mult_1_right mult_ac
    92   word_order_trans ~> order_trans
    93   word_order_refl ~> order_refl
    94   word_order_antisym ~> order_antisym
    95   word_order_linear ~> linorder_linear
    96   lenw1_zero_neq_one ~> zero_neq_one
    97   word_number_of_eq ~> number_of_eq
    98 
    99 * Clarified attribute "mono_set": pure declararation without modifying
   100 the result of the fact expression.
   101 
   102 * "Transitive_Closure.ntrancl": bounded transitive closure on
   103 relations.
   104 
   105 * Constant "Set.not_member" now qualifed.  INCOMPATIBILITY.
   106 
   107 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
   108 
   109 * Theory Int: Discontinued many legacy theorems specific to type int.
   110 INCOMPATIBILITY, use the corresponding generic theorems instead.
   111 
   112   zminus_zminus ~> minus_minus
   113   zminus_0 ~> minus_zero
   114   zminus_zadd_distrib ~> minus_add_distrib
   115   zadd_commute ~> add_commute
   116   zadd_assoc ~> add_assoc
   117   zadd_left_commute ~> add_left_commute
   118   zadd_ac ~> add_ac
   119   zmult_ac ~> mult_ac
   120   zadd_0 ~> add_0_left
   121   zadd_0_right ~> add_0_right
   122   zadd_zminus_inverse2 ~> left_minus
   123   zmult_zminus ~> mult_minus_left
   124   zmult_commute ~> mult_commute
   125   zmult_assoc ~> mult_assoc
   126   zadd_zmult_distrib ~> left_distrib
   127   zadd_zmult_distrib2 ~> right_distrib
   128   zdiff_zmult_distrib ~> left_diff_distrib
   129   zdiff_zmult_distrib2 ~> right_diff_distrib
   130   zmult_1 ~> mult_1_left
   131   zmult_1_right ~> mult_1_right
   132   zle_refl ~> order_refl
   133   zle_trans ~> order_trans
   134   zle_antisym ~> order_antisym
   135   zle_linear ~> linorder_linear
   136   zless_linear ~> linorder_less_linear
   137   zadd_left_mono ~> add_left_mono
   138   zadd_strict_right_mono ~> add_strict_right_mono
   139   zadd_zless_mono ~> add_less_le_mono
   140   int_0_less_1 ~> zero_less_one
   141   int_0_neq_1 ~> zero_neq_one
   142   zless_le ~> less_le
   143   zpower_zadd_distrib ~> power_add
   144   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
   145   zero_le_zpower_abs ~> zero_le_power_abs
   146 
   147 * Theory Deriv: Renamed
   148 
   149   DERIV_nonneg_imp_nonincreasing ~> DERIV_nonneg_imp_nondecreasing
   150 
   151 * New "case_product" attribute to generate a case rule doing multiple
   152 case distinctions at the same time.  E.g.
   153 
   154   list.exhaust [case_product nat.exhaust]
   155 
   156 produces a rule which can be used to perform case distinction on both
   157 a list and a nat.
   158 
   159 * Quickcheck:
   160   - Quickcheck returns variable assignments as counterexamples, which
   161     allows to reveal the underspecification of functions under test.
   162     For example, refuting "hd xs = x", it presents the variable
   163     assignment xs = [] and x = a1 as a counterexample, assuming that
   164     any property is false whenever "hd []" occurs in it.
   165     These counterexample are marked as potentially spurious, as
   166     Quickcheck also returns "xs = []" as a counterexample to the
   167     obvious theorem "hd xs = hd xs".
   168     After finding a potentially spurious counterexample, Quickcheck
   169     continues searching for genuine ones.
   170     By default, Quickcheck shows potentially spurious and genuine
   171     counterexamples. The option "genuine_only" sets quickcheck to
   172     only show genuine counterexamples.
   173  
   174 * Nitpick:
   175   - Fixed infinite loop caused by the 'peephole_optim' option and
   176     affecting 'rat' and 'real'.
   177 
   178 * Sledgehammer:
   179   - Added "lam_trans" and "minimize" options.
   180   - Renamed "slicing" ("no_slicing") option to "slice" ("dont_slice").
   181 
   182 * Metis:
   183   - Added possibility to specify lambda translations scheme as a
   184     parenthesized argument (e.g., "by (metis (lam_lifting) ...)").
   185 
   186 
   187 *** FOL ***
   188 
   189 * New "case_product" attribute (see HOL).
   190 
   191 
   192 *** ML ***
   193 
   194 * Antiquotation @{attributes [...]} embeds attribute source
   195 representation into the ML text, which is particularly useful with
   196 declarations like Local_Theory.note.
   197 
   198 * Structure Proof_Context follows standard naming scheme.  Old
   199 ProofContext has been discontinued.  INCOMPATIBILITY.
   200 
   201 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   202 change of semantics: update is applied to auxiliary local theory
   203 context as well.
   204 
   205 * Modernized some old-style infix operations:
   206 
   207   addeqcongs    ~> Simplifier.add_eqcong
   208   deleqcongs    ~> Simplifier.del_eqcong
   209   addcongs      ~> Simplifier.add_cong
   210   delcongs      ~> Simplifier.del_cong
   211   setmksimps    ~> Simplifier.set_mksimps
   212   setmkcong     ~> Simplifier.set_mkcong
   213   setmksym      ~> Simplifier.set_mksym
   214   setmkeqTrue   ~> Simplifier.set_mkeqTrue
   215   settermless   ~> Simplifier.set_termless
   216   setsubgoaler  ~> Simplifier.set_subgoaler
   217   addsplits     ~> Splitter.add_split
   218   delsplits     ~> Splitter.del_split
   219 
   220 
   221 
   222 New in Isabelle2011-1 (October 2011)
   223 ------------------------------------
   224 
   225 *** General ***
   226 
   227 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   228 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   229 
   230   - Management of multiple theory files directly from the editor
   231     buffer store -- bypassing the file-system (no requirement to save
   232     files for checking).
   233 
   234   - Markup of formal entities within the text buffer, with semantic
   235     highlighting, tooltips and hyperlinks to jump to defining source
   236     positions.
   237 
   238   - Improved text rendering, with sub/superscripts in the source
   239     buffer (including support for copy/paste wrt. output panel, HTML
   240     theory output and other non-Isabelle text boxes).
   241 
   242   - Refined scheduling of proof checking and printing of results,
   243     based on interactive editor view.  (Note: jEdit folding and
   244     narrowing allows to restrict buffer perspectives explicitly.)
   245 
   246   - Reduced CPU performance requirements, usable on machines with few
   247     cores.
   248 
   249   - Reduced memory requirements due to pruning of unused document
   250     versions (garbage collection).
   251 
   252 See also ~~/src/Tools/jEdit/README.html for further information,
   253 including some remaining limitations.
   254 
   255 * Theory loader: source files are exclusively located via the master
   256 directory of each theory node (where the .thy file itself resides).
   257 The global load path (such as src/HOL/Library) has been discontinued.
   258 Note that the path element ~~ may be used to reference theories in the
   259 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   260 INCOMPATIBILITY.
   261 
   262 * Theory loader: source files are identified by content via SHA1
   263 digests.  Discontinued former path/modtime identification and optional
   264 ISABELLE_FILE_IDENT plugin scripts.
   265 
   266 * Parallelization of nested Isar proofs is subject to
   267 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   268 usedir option -Q.
   269 
   270 * Name space: former unsynchronized references are now proper
   271 configuration options, with more conventional names:
   272 
   273   long_names   ~> names_long
   274   short_names  ~> names_short
   275   unique_names ~> names_unique
   276 
   277 Minor INCOMPATIBILITY, need to declare options in context like this:
   278 
   279   declare [[names_unique = false]]
   280 
   281 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   282 that the result needs to be unique, which means fact specifications
   283 may have to be refined after enriching a proof context.
   284 
   285 * Attribute "case_names" has been refined: the assumptions in each case
   286 can be named now by following the case name with [name1 name2 ...].
   287 
   288 * Isabelle/Isar reference manual has been updated and extended:
   289   - "Synopsis" provides a catalog of main Isar language concepts.
   290   - Formal references in syntax diagrams, via @{rail} antiquotation.
   291   - Updated material from classic "ref" manual, notably about
   292     "Classical Reasoner".
   293 
   294 
   295 *** HOL ***
   296 
   297 * Class bot and top require underlying partial order rather than
   298 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   299 
   300 * Class complete_lattice: generalized a couple of lemmas from sets;
   301 generalized theorems INF_cong and SUP_cong.  New type classes for
   302 complete boolean algebras and complete linear orders.  Lemmas
   303 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   304 class complete_linorder.
   305 
   306 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   307 Sup_fun_def, Inf_apply, Sup_apply.
   308 
   309 Removed redundant lemmas (the right hand side gives hints how to
   310 replace them for (metis ...), or (simp only: ...) proofs):
   311 
   312   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   313   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   314   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   315   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   316   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   317   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   318   Inter_def ~> INF_def, image_def
   319   Union_def ~> SUP_def, image_def
   320   INT_eq ~> INF_def, and image_def
   321   UN_eq ~> SUP_def, and image_def
   322   INF_subset ~> INF_superset_mono [OF _ order_refl]
   323 
   324 More consistent and comprehensive names:
   325 
   326   INTER_eq_Inter_image ~> INF_def
   327   UNION_eq_Union_image ~> SUP_def
   328   INFI_def ~> INF_def
   329   SUPR_def ~> SUP_def
   330   INF_leI ~> INF_lower
   331   INF_leI2 ~> INF_lower2
   332   le_INFI ~> INF_greatest
   333   le_SUPI ~> SUP_upper
   334   le_SUPI2 ~> SUP_upper2
   335   SUP_leI ~> SUP_least
   336   INFI_bool_eq ~> INF_bool_eq
   337   SUPR_bool_eq ~> SUP_bool_eq
   338   INFI_apply ~> INF_apply
   339   SUPR_apply ~> SUP_apply
   340   INTER_def ~> INTER_eq
   341   UNION_def ~> UNION_eq
   342 
   343 INCOMPATIBILITY.
   344 
   345 * Renamed theory Complete_Lattice to Complete_Lattices.
   346 INCOMPATIBILITY.
   347 
   348 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   349 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   350 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   351 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   352 
   353 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   354 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   355 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   356 INCOMPATIBILITY.
   357 
   358 * Added syntactic classes "inf" and "sup" for the respective
   359 constants.  INCOMPATIBILITY: Changes in the argument order of the
   360 (mostly internal) locale predicates for some derived classes.
   361 
   362 * Theorem collections ball_simps and bex_simps do not contain theorems
   363 referring to UNION any longer; these have been moved to collection
   364 UN_ball_bex_simps.  INCOMPATIBILITY.
   365 
   366 * Theory Archimedean_Field: floor now is defined as parameter of a
   367 separate type class floor_ceiling.
   368 
   369 * Theory Finite_Set: more coherent development of fold_set locales:
   370 
   371     locale fun_left_comm ~> locale comp_fun_commute
   372     locale fun_left_comm_idem ~> locale comp_fun_idem
   373 
   374 Both use point-free characterization; interpretation proofs may need
   375 adjustment.  INCOMPATIBILITY.
   376 
   377 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   378 accordance with standard mathematical terminology. INCOMPATIBILITY.
   379 
   380 * Theory Complex_Main: The locale interpretations for the
   381 bounded_linear and bounded_bilinear locales have been removed, in
   382 order to reduce the number of duplicate lemmas. Users must use the
   383 original names for distributivity theorems, potential INCOMPATIBILITY.
   384 
   385   divide.add ~> add_divide_distrib
   386   divide.diff ~> diff_divide_distrib
   387   divide.setsum ~> setsum_divide_distrib
   388   mult.add_right ~> right_distrib
   389   mult.diff_right ~> right_diff_distrib
   390   mult_right.setsum ~> setsum_right_distrib
   391   mult_left.diff ~> left_diff_distrib
   392 
   393 * Theory Complex_Main: Several redundant theorems have been removed or
   394 replaced by more general versions. INCOMPATIBILITY.
   395 
   396   real_diff_def ~> minus_real_def
   397   real_divide_def ~> divide_real_def
   398   real_less_def ~> less_le
   399   real_abs_def ~> abs_real_def
   400   real_sgn_def ~> sgn_real_def
   401   real_mult_commute ~> mult_commute
   402   real_mult_assoc ~> mult_assoc
   403   real_mult_1 ~> mult_1_left
   404   real_add_mult_distrib ~> left_distrib
   405   real_zero_not_eq_one ~> zero_neq_one
   406   real_mult_inverse_left ~> left_inverse
   407   INVERSE_ZERO ~> inverse_zero
   408   real_le_refl ~> order_refl
   409   real_le_antisym ~> order_antisym
   410   real_le_trans ~> order_trans
   411   real_le_linear ~> linear
   412   real_le_eq_diff ~> le_iff_diff_le_0
   413   real_add_left_mono ~> add_left_mono
   414   real_mult_order ~> mult_pos_pos
   415   real_mult_less_mono2 ~> mult_strict_left_mono
   416   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   417   real_0_le_divide_iff ~> zero_le_divide_iff
   418   realpow_two_disj ~> power2_eq_iff
   419   real_squared_diff_one_factored ~> square_diff_one_factored
   420   realpow_two_diff ~> square_diff_square_factored
   421   reals_complete2 ~> complete_real
   422   real_sum_squared_expand ~> power2_sum
   423   exp_ln_eq ~> ln_unique
   424   expi_add ~> exp_add
   425   expi_zero ~> exp_zero
   426   lemma_DERIV_subst ~> DERIV_cong
   427   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   428   LIMSEQ_const ~> tendsto_const
   429   LIMSEQ_norm ~> tendsto_norm
   430   LIMSEQ_add ~> tendsto_add
   431   LIMSEQ_minus ~> tendsto_minus
   432   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   433   LIMSEQ_diff ~> tendsto_diff
   434   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   435   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   436   LIMSEQ_mult ~> tendsto_mult
   437   LIMSEQ_inverse ~> tendsto_inverse
   438   LIMSEQ_divide ~> tendsto_divide
   439   LIMSEQ_pow ~> tendsto_power
   440   LIMSEQ_setsum ~> tendsto_setsum
   441   LIMSEQ_setprod ~> tendsto_setprod
   442   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   443   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   444   LIMSEQ_imp_rabs ~> tendsto_rabs
   445   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   446   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   447   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   448   LIMSEQ_Complex ~> tendsto_Complex
   449   LIM_ident ~> tendsto_ident_at
   450   LIM_const ~> tendsto_const
   451   LIM_add ~> tendsto_add
   452   LIM_add_zero ~> tendsto_add_zero
   453   LIM_minus ~> tendsto_minus
   454   LIM_diff ~> tendsto_diff
   455   LIM_norm ~> tendsto_norm
   456   LIM_norm_zero ~> tendsto_norm_zero
   457   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   458   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   459   LIM_rabs ~> tendsto_rabs
   460   LIM_rabs_zero ~> tendsto_rabs_zero
   461   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   462   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   463   LIM_compose ~> tendsto_compose
   464   LIM_mult ~> tendsto_mult
   465   LIM_scaleR ~> tendsto_scaleR
   466   LIM_of_real ~> tendsto_of_real
   467   LIM_power ~> tendsto_power
   468   LIM_inverse ~> tendsto_inverse
   469   LIM_sgn ~> tendsto_sgn
   470   isCont_LIM_compose ~> isCont_tendsto_compose
   471   bounded_linear.LIM ~> bounded_linear.tendsto
   472   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   473   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   474   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   475   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   476   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   477   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   478 
   479 * Theory Complex_Main: The definition of infinite series was
   480 generalized.  Now it is defined on the type class {topological_space,
   481 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   482 
   483 * Theory Complex_Main: The complex exponential function "expi" is now
   484 a type-constrained abbreviation for "exp :: complex => complex"; thus
   485 several polymorphic lemmas about "exp" are now applicable to "expi".
   486 
   487 * Code generation:
   488 
   489   - Theory Library/Code_Char_ord provides native ordering of
   490     characters in the target language.
   491 
   492   - Commands code_module and code_library are legacy, use export_code
   493     instead.
   494 
   495   - Method "evaluation" is legacy, use method "eval" instead.
   496 
   497   - Legacy evaluator "SML" is deactivated by default.  May be
   498     reactivated by the following theory command:
   499 
   500       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   501 
   502 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   503 
   504 * New proof method "induction" that gives induction hypotheses the
   505 name "IH", thus distinguishing them from further hypotheses that come
   506 from rule induction.  The latter are still called "hyps".  Method
   507 "induction" is a thin wrapper around "induct" and follows the same
   508 syntax.
   509 
   510 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
   511 still available as a legacy feature for some time.
   512 
   513 * Nitpick:
   514   - Added "need" and "total_consts" options.
   515   - Reintroduced "show_skolems" option by popular demand.
   516   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   517     INCOMPATIBILITY.
   518 
   519 * Sledgehammer:
   520   - Use quasi-sound (and efficient) translations by default.
   521   - Added support for the following provers: E-ToFoF, LEO-II,
   522     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
   523   - Automatically preplay and minimize proofs before showing them if
   524     this can be done within reasonable time.
   525   - sledgehammer available_provers ~> sledgehammer supported_provers.
   526     INCOMPATIBILITY.
   527   - Added "preplay_timeout", "slicing", "type_enc", "sound",
   528     "max_mono_iters", and "max_new_mono_instances" options.
   529   - Removed "explicit_apply" and "full_types" options as well as "Full
   530     Types" Proof General menu item. INCOMPATIBILITY.
   531 
   532 * Metis:
   533   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   534   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
   535     INCOMPATIBILITY.
   536 
   537 * Command 'try':
   538   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
   539     "elim:" options. INCOMPATIBILITY.
   540   - Introduced 'try' that not only runs 'try_methods' but also
   541     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
   542 
   543 * Quickcheck:
   544   - Added "eval" option to evaluate terms for the found counterexample
   545     (currently only supported by the default (exhaustive) tester).
   546   - Added post-processing of terms to obtain readable counterexamples
   547     (currently only supported by the default (exhaustive) tester).
   548   - New counterexample generator quickcheck[narrowing] enables
   549     narrowing-based testing.  Requires the Glasgow Haskell compiler
   550     with its installation location defined in the Isabelle settings
   551     environment as ISABELLE_GHC.
   552   - Removed quickcheck tester "SML" based on the SML code generator
   553     (formly in HOL/Library).
   554 
   555 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
   556 use 'partial_function' instead.
   557 
   558 * Theory Library/Extended_Reals replaces now the positive extended
   559 reals found in probability theory. This file is extended by
   560 Multivariate_Analysis/Extended_Real_Limits.
   561 
   562 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
   563 from where it must be imported explicitly if it is really required.
   564 INCOMPATIBILITY.
   565 
   566 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
   567 been moved here.  INCOMPATIBILITY.
   568 
   569 * Theory Library/Saturated provides type of numbers with saturated
   570 arithmetic.
   571 
   572 * Theory Library/Product_Lattice defines a pointwise ordering for the
   573 product type 'a * 'b, and provides instance proofs for various order
   574 and lattice type classes.
   575 
   576 * Theory Library/Countable now provides the "countable_datatype" proof
   577 method for proving "countable" class instances for datatypes.
   578 
   579 * Theory Library/Cset_Monad allows do notation for computable sets
   580 (cset) via the generic monad ad-hoc overloading facility.
   581 
   582 * Library: Theories of common data structures are split into theories
   583 for implementation, an invariant-ensuring type, and connection to an
   584 abstract type. INCOMPATIBILITY.
   585 
   586   - RBT is split into RBT and RBT_Mapping.
   587   - AssocList is split and renamed into AList and AList_Mapping.
   588   - DList is split into DList_Impl, DList, and DList_Cset.
   589   - Cset is split into Cset and List_Cset.
   590 
   591 * Theory Library/Nat_Infinity has been renamed to
   592 Library/Extended_Nat, with name changes of the following types and
   593 constants:
   594 
   595   type inat   ~> type enat
   596   Fin         ~> enat
   597   Infty       ~> infinity (overloaded)
   598   iSuc        ~> eSuc
   599   the_Fin     ~> the_enat
   600 
   601 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   602 been renamed accordingly. INCOMPATIBILITY.
   603 
   604 * Session Multivariate_Analysis: The euclidean_space type class now
   605 fixes a constant "Basis :: 'a set" consisting of the standard
   606 orthonormal basis for the type. Users now have the option of
   607 quantifying over this set instead of using the "basis" function, e.g.
   608 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
   609 
   610 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   611 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   612 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   613 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   614 changed to match. Definition theorems for overloaded constants now use
   615 the standard "foo_vec_def" naming scheme. A few other theorems have
   616 been renamed as follows (INCOMPATIBILITY):
   617 
   618   Cart_eq          ~> vec_eq_iff
   619   dist_nth_le_cart ~> dist_vec_nth_le
   620   tendsto_vector   ~> vec_tendstoI
   621   Cauchy_vector    ~> vec_CauchyI
   622 
   623 * Session Multivariate_Analysis: Several duplicate theorems have been
   624 removed, and other theorems have been renamed or replaced with more
   625 general versions. INCOMPATIBILITY.
   626 
   627   finite_choice ~> finite_set_choice
   628   eventually_conjI ~> eventually_conj
   629   eventually_and ~> eventually_conj_iff
   630   eventually_false ~> eventually_False
   631   setsum_norm ~> norm_setsum
   632   Lim_sequentially ~> LIMSEQ_def
   633   Lim_ident_at ~> LIM_ident
   634   Lim_const ~> tendsto_const
   635   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   636   Lim_neg ~> tendsto_minus
   637   Lim_add ~> tendsto_add
   638   Lim_sub ~> tendsto_diff
   639   Lim_mul ~> tendsto_scaleR
   640   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   641   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   642   Lim_linear ~> bounded_linear.tendsto
   643   Lim_component ~> tendsto_euclidean_component
   644   Lim_component_cart ~> tendsto_vec_nth
   645   Lim_inner ~> tendsto_inner [OF tendsto_const]
   646   dot_lsum ~> inner_setsum_left
   647   dot_rsum ~> inner_setsum_right
   648   continuous_cmul ~> continuous_scaleR [OF continuous_const]
   649   continuous_neg ~> continuous_minus
   650   continuous_sub ~> continuous_diff
   651   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
   652   continuous_mul ~> continuous_scaleR
   653   continuous_inv ~> continuous_inverse
   654   continuous_at_within_inv ~> continuous_at_within_inverse
   655   continuous_at_inv ~> continuous_at_inverse
   656   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
   657   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
   658   continuous_at_component ~> continuous_component [OF continuous_at_id]
   659   continuous_on_neg ~> continuous_on_minus
   660   continuous_on_sub ~> continuous_on_diff
   661   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   662   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   663   continuous_on_mul ~> continuous_on_scaleR
   664   continuous_on_mul_real ~> continuous_on_mult
   665   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   666   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
   667   continuous_on_inverse ~> continuous_on_inv
   668   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
   669   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
   670   subset_interior ~> interior_mono
   671   subset_closure ~> closure_mono
   672   closure_univ ~> closure_UNIV
   673   real_arch_lt ~> reals_Archimedean2
   674   real_arch ~> reals_Archimedean3
   675   real_abs_norm ~> abs_norm_cancel
   676   real_abs_sub_norm ~> norm_triangle_ineq3
   677   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
   678 
   679 * Session HOL-Probability:
   680   - Caratheodory's extension lemma is now proved for ring_of_sets.
   681   - Infinite products of probability measures are now available.
   682   - Sigma closure is independent, if the generator is independent
   683   - Use extended reals instead of positive extended
   684     reals. INCOMPATIBILITY.
   685 
   686 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
   687 
   688   expand_fun_below ~> fun_below_iff
   689   below_fun_ext ~> fun_belowI
   690   expand_cfun_eq ~> cfun_eq_iff
   691   ext_cfun ~> cfun_eqI
   692   expand_cfun_below ~> cfun_below_iff
   693   below_cfun_ext ~> cfun_belowI
   694   monofun_fun_fun ~> fun_belowD
   695   monofun_fun_arg ~> monofunE
   696   monofun_lub_fun ~> adm_monofun [THEN admD]
   697   cont_lub_fun ~> adm_cont [THEN admD]
   698   cont2cont_Rep_CFun ~> cont2cont_APP
   699   cont_Rep_CFun_app ~> cont_APP_app
   700   cont_Rep_CFun_app_app ~> cont_APP_app_app
   701   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
   702   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
   703   contlub_cfun ~> lub_APP [symmetric]
   704   contlub_LAM ~> lub_LAM [symmetric]
   705   thelubI ~> lub_eqI
   706   UU_I ~> bottomI
   707   lift_distinct1 ~> lift.distinct(1)
   708   lift_distinct2 ~> lift.distinct(2)
   709   Def_not_UU ~> lift.distinct(2)
   710   Def_inject ~> lift.inject
   711   below_UU_iff ~> below_bottom_iff
   712   eq_UU_iff ~> eq_bottom_iff
   713 
   714 
   715 *** Document preparation ***
   716 
   717 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   718 isar-ref manual, both for description and actual application of the
   719 same.
   720 
   721 * Antiquotation @{value} evaluates the given term and presents its
   722 result.
   723 
   724 * Antiquotations: term style "isub" provides ad-hoc conversion of
   725 variables x1, y23 into subscripted form x\<^isub>1,
   726 y\<^isub>2\<^isub>3.
   727 
   728 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   729 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   730 
   731 * Localized \isabellestyle switch can be used within blocks or groups
   732 like this:
   733 
   734   \isabellestyle{it}  %preferred default
   735   {\isabellestylett @{text "typewriter stuff"}}
   736 
   737 * Discontinued special treatment of hard tabulators.  Implicit
   738 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
   739 layouts.
   740 
   741 
   742 *** ML ***
   743 
   744 * The inner syntax of sort/type/term/prop supports inlined YXML
   745 representations within quoted string tokens.  By encoding logical
   746 entities via Term_XML (in ML or Scala) concrete syntax can be
   747 bypassed, which is particularly useful for producing bits of text
   748 under external program control.
   749 
   750 * Antiquotations for ML and document preparation are managed as theory
   751 data, which requires explicit setup.
   752 
   753 * Isabelle_Process.is_active allows tools to check if the official
   754 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   755 (better known as Proof General).
   756 
   757 * Structure Proof_Context follows standard naming scheme.  Old
   758 ProofContext is still available for some time as legacy alias.
   759 
   760 * Structure Timing provides various operations for timing; supersedes
   761 former start_timing/end_timing etc.
   762 
   763 * Path.print is the official way to show file-system paths to users
   764 (including quotes etc.).
   765 
   766 * Inner syntax: identifiers in parse trees of generic categories
   767 "logic", "aprop", "idt" etc. carry position information (disguised as
   768 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   769 translations that choke on unexpected type constraints.  Positions can
   770 be stripped in ML translations via Syntax.strip_positions /
   771 Syntax.strip_positions_ast, or via the syntax constant
   772 "_strip_positions" within parse trees.  As last resort, positions can
   773 be disabled via the configuration option Syntax.positions, which is
   774 called "syntax_positions" in Isar attribute syntax.
   775 
   776 * Discontinued special status of various ML structures that contribute
   777 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   778 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   779 refer directly to Ast.Constant, Lexicon.is_identifier,
   780 Syntax_Trans.mk_binder_tr etc.
   781 
   782 * Typed print translation: discontinued show_sorts argument, which is
   783 already available via context of "advanced" translation.
   784 
   785 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   786 goal states; body tactic needs to address all subgoals uniformly.
   787 
   788 * Slightly more special eq_list/eq_set, with shortcut involving
   789 pointer equality (assumes that eq relation is reflexive).
   790 
   791 * Classical tactics use proper Proof.context instead of historic types
   792 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   793 operate directly on Proof.context.  Raw type claset retains its use as
   794 snapshot of the classical context, which can be recovered via
   795 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   796 INCOMPATIBILITY, classical tactics and derived proof methods require
   797 proper Proof.context.
   798 
   799 
   800 *** System ***
   801 
   802 * Discontinued support for Poly/ML 5.2, which was the last version
   803 without proper multithreading and TimeLimit implementation.
   804 
   805 * Discontinued old lib/scripts/polyml-platform, which has been
   806 obsolete since Isabelle2009-2.
   807 
   808 * Various optional external tools are referenced more robustly and
   809 uniformly by explicit Isabelle settings as follows:
   810 
   811   ISABELLE_CSDP   (formerly CSDP_EXE)
   812   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
   813   ISABELLE_OCAML  (formerly EXEC_OCAML)
   814   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
   815   ISABELLE_YAP    (formerly EXEC_YAP)
   816 
   817 Note that automated detection from the file-system or search path has
   818 been discontinued.  INCOMPATIBILITY.
   819 
   820 * Scala layer provides JVM method invocation service for static
   821 methods of type (String)String, see Invoke_Scala.method in ML.  For
   822 example:
   823 
   824   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   825 
   826 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
   827 this allows to pass structured values between ML and Scala.
   828 
   829 * The IsabelleText fonts includes some further glyphs to support the
   830 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
   831 installed a local copy (which is normally *not* required) need to
   832 delete or update it from ~~/lib/fonts/.
   833 
   834 
   835 
   836 New in Isabelle2011 (January 2011)
   837 ----------------------------------
   838 
   839 *** General ***
   840 
   841 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   842 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   843 useful tooltips and hyperlinks produced from its static analysis.  The
   844 bundled component provides an executable Isabelle tool that can be run
   845 like this:
   846 
   847   Isabelle2011/bin/isabelle jedit
   848 
   849 * Significantly improved Isabelle/Isar implementation manual.
   850 
   851 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   852 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   853 while the default heap location within that directory lacks that extra
   854 suffix.  This isolates multiple Isabelle installations from each
   855 other, avoiding problems with old settings in new versions.
   856 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   857 
   858 * Source files are always encoded as UTF-8, instead of old-fashioned
   859 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   860 the following package declarations:
   861 
   862   \usepackage[utf8]{inputenc}
   863   \usepackage{textcomp}
   864 
   865 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   866 a Unicode character is treated as a single symbol, not a sequence of
   867 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   868 contain symbols without further backslash escapes, Unicode can now be
   869 used here as well.  Recall that Symbol.explode in ML provides a
   870 consistent view on symbols, while raw explode (or String.explode)
   871 merely give a byte-oriented representation.
   872 
   873 * Theory loader: source files are primarily located via the master
   874 directory of each theory node (where the .thy file itself resides).
   875 The global load path is still partially available as legacy feature.
   876 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   877 explicit paths, relatively to the theory.
   878 
   879 * Special treatment of ML file names has been discontinued.
   880 Historically, optional extensions .ML or .sml were added on demand --
   881 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   882 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   883 
   884 * Various options that affect pretty printing etc. are now properly
   885 handled within the context via configuration options, instead of
   886 unsynchronized references or print modes.  There are both ML Config.T
   887 entities and Isar declaration attributes to access these.
   888 
   889   ML (Config.T)                 Isar (attribute)
   890 
   891   eta_contract                  eta_contract
   892   show_brackets                 show_brackets
   893   show_sorts                    show_sorts
   894   show_types                    show_types
   895   show_question_marks           show_question_marks
   896   show_consts                   show_consts
   897   show_abbrevs                  show_abbrevs
   898 
   899   Syntax.ast_trace              syntax_ast_trace
   900   Syntax.ast_stat               syntax_ast_stat
   901   Syntax.ambiguity_level        syntax_ambiguity_level
   902 
   903   Goal_Display.goals_limit      goals_limit
   904   Goal_Display.show_main_goal   show_main_goal
   905 
   906   Method.rule_trace             rule_trace
   907 
   908   Thy_Output.display            thy_output_display
   909   Thy_Output.quotes             thy_output_quotes
   910   Thy_Output.indent             thy_output_indent
   911   Thy_Output.source             thy_output_source
   912   Thy_Output.break              thy_output_break
   913 
   914 Note that corresponding "..._default" references in ML may only be
   915 changed globally at the ROOT session setup, but *not* within a theory.
   916 The option "show_abbrevs" supersedes the former print mode
   917 "no_abbrevs" with inverted meaning.
   918 
   919 * More systematic naming of some configuration options.
   920 INCOMPATIBILITY.
   921 
   922   trace_simp  ~>  simp_trace
   923   debug_simp  ~>  simp_debug
   924 
   925 * Support for real valued configuration options, using simplistic
   926 floating-point notation that coincides with the inner syntax for
   927 float_token.
   928 
   929 * Support for real valued preferences (with approximative PGIP type):
   930 front-ends need to accept "pgint" values in float notation.
   931 INCOMPATIBILITY.
   932 
   933 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   934 DejaVu Sans.
   935 
   936 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   937 
   938 
   939 *** Pure ***
   940 
   941 * Command 'type_synonym' (with single argument) replaces somewhat
   942 outdated 'types', which is still available as legacy feature for some
   943 time.
   944 
   945 * Command 'nonterminal' (with 'and' separated list of arguments)
   946 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   947 
   948 * Command 'notepad' replaces former 'example_proof' for
   949 experimentation in Isar without any result.  INCOMPATIBILITY.
   950 
   951 * Locale interpretation commands 'interpret' and 'sublocale' accept
   952 lists of equations to map definitions in a locale to appropriate
   953 entities in the context of the interpretation.  The 'interpretation'
   954 command already provided this functionality.
   955 
   956 * Diagnostic command 'print_dependencies' prints the locale instances
   957 that would be activated if the specified expression was interpreted in
   958 the current context.  Variant "print_dependencies!" assumes a context
   959 without interpretations.
   960 
   961 * Diagnostic command 'print_interps' prints interpretations in proofs
   962 in addition to interpretations in theories.
   963 
   964 * Discontinued obsolete 'global' and 'local' commands to manipulate
   965 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   966 Sign.root_path and Sign.local_path may be applied directly where this
   967 feature is still required for historical reasons.
   968 
   969 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   970 'definition' instead.
   971 
   972 * The "prems" fact, which refers to the accidental collection of
   973 foundational premises in the context, is now explicitly marked as
   974 legacy feature and will be discontinued soon.  Consider using "assms"
   975 of the head statement or reference facts by explicit names.
   976 
   977 * Document antiquotations @{class} and @{type} print classes and type
   978 constructors.
   979 
   980 * Document antiquotation @{file} checks file/directory entries within
   981 the local file system.
   982 
   983 
   984 *** HOL ***
   985 
   986 * Coercive subtyping: functions can be declared as coercions and type
   987 inference will add them as necessary upon input of a term.  Theory
   988 Complex_Main declares real :: nat => real and real :: int => real as
   989 coercions. A coercion function f is declared like this:
   990 
   991   declare [[coercion f]]
   992 
   993 To lift coercions through type constructors (e.g. from nat => real to
   994 nat list => real list), map functions can be declared, e.g.
   995 
   996   declare [[coercion_map map]]
   997 
   998 Currently coercion inference is activated only in theories including
   999 real numbers, i.e. descendants of Complex_Main.  This is controlled by
  1000 the configuration option "coercion_enabled", e.g. it can be enabled in
  1001 other theories like this:
  1002 
  1003   declare [[coercion_enabled]]
  1004 
  1005 * Command 'partial_function' provides basic support for recursive
  1006 function definitions over complete partial orders.  Concrete instances
  1007 are provided for i) the option type, ii) tail recursion on arbitrary
  1008 types, and iii) the heap monad of Imperative_HOL.  See
  1009 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
  1010 for examples.
  1011 
  1012 * Function package: f.psimps rules are no longer implicitly declared
  1013 as [simp].  INCOMPATIBILITY.
  1014 
  1015 * Datatype package: theorems generated for executable equality (class
  1016 "eq") carry proper names and are treated as default code equations.
  1017 
  1018 * Inductive package: now offers command 'inductive_simps' to
  1019 automatically derive instantiated and simplified equations for
  1020 inductive predicates, similar to 'inductive_cases'.
  1021 
  1022 * Command 'enriched_type' allows to register properties of the
  1023 functorial structure of types.
  1024 
  1025 * Improved infrastructure for term evaluation using code generator
  1026 techniques, in particular static evaluation conversions.
  1027 
  1028 * Code generator: Scala (2.8 or higher) has been added to the target
  1029 languages.
  1030 
  1031 * Code generator: globbing constant expressions "*" and "Theory.*"
  1032 have been replaced by the more idiomatic "_" and "Theory._".
  1033 INCOMPATIBILITY.
  1034 
  1035 * Code generator: export_code without explicit file declaration prints
  1036 to standard output.  INCOMPATIBILITY.
  1037 
  1038 * Code generator: do not print function definitions for case
  1039 combinators any longer.
  1040 
  1041 * Code generator: simplification with rules determined with
  1042 src/Tools/Code/code_simp.ML and method "code_simp".
  1043 
  1044 * Code generator for records: more idiomatic representation of record
  1045 types.  Warning: records are not covered by ancient SML code
  1046 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
  1047 rep_datatype declaration helps to succeed then:
  1048 
  1049   record 'a foo = ...
  1050   ...
  1051   rep_datatype foo_ext ...
  1052 
  1053 * Records: logical foundation type for records does not carry a
  1054 '_type' suffix any longer (obsolete due to authentic syntax).
  1055 INCOMPATIBILITY.
  1056 
  1057 * Quickcheck now by default uses exhaustive testing instead of random
  1058 testing.  Random testing can be invoked by "quickcheck [random]",
  1059 exhaustive testing by "quickcheck [exhaustive]".
  1060 
  1061 * Quickcheck instantiates polymorphic types with small finite
  1062 datatypes by default. This enables a simple execution mechanism to
  1063 handle quantifiers and function equality over the finite datatypes.
  1064 
  1065 * Quickcheck random generator has been renamed from "code" to
  1066 "random".  INCOMPATIBILITY.
  1067 
  1068 * Quickcheck now has a configurable time limit which is set to 30
  1069 seconds by default. This can be changed by adding [timeout = n] to the
  1070 quickcheck command. The time limit for Auto Quickcheck is still set
  1071 independently.
  1072 
  1073 * Quickcheck in locales considers interpretations of that locale for
  1074 counter example search.
  1075 
  1076 * Sledgehammer:
  1077   - Added "smt" and "remote_smt" provers based on the "smt" proof
  1078     method. See the Sledgehammer manual for details ("isabelle doc
  1079     sledgehammer").
  1080   - Renamed commands:
  1081     sledgehammer atp_info ~> sledgehammer running_provers
  1082     sledgehammer atp_kill ~> sledgehammer kill_provers
  1083     sledgehammer available_atps ~> sledgehammer available_provers
  1084     INCOMPATIBILITY.
  1085   - Renamed options:
  1086     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
  1087     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
  1088     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
  1089     (and "ms" and "min" are no longer supported)
  1090     INCOMPATIBILITY.
  1091 
  1092 * Nitpick:
  1093   - Renamed options:
  1094     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
  1095     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
  1096     INCOMPATIBILITY.
  1097   - Added support for partial quotient types.
  1098   - Added local versions of the "Nitpick.register_xxx" functions.
  1099   - Added "whack" option.
  1100   - Allow registration of quotient types as codatatypes.
  1101   - Improved "merge_type_vars" option to merge more types.
  1102   - Removed unsound "fast_descrs" option.
  1103   - Added custom symmetry breaking for datatypes, making it possible to reach
  1104     higher cardinalities.
  1105   - Prevent the expansion of too large definitions.
  1106 
  1107 * Proof methods "metis" and "meson" now have configuration options
  1108 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
  1109 to diagnose these tools. E.g.
  1110 
  1111     using [[metis_trace = true]]
  1112 
  1113 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1114 manually as command 'solve_direct'.
  1115 
  1116 * The default SMT solver Z3 must be enabled explicitly (due to
  1117 licensing issues) by setting the environment variable
  1118 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1119 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1120 changing the SMT solver is done via the configuration option
  1121 "smt_solver".
  1122 
  1123 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1124 i.e. "remote_cvc3" and "remote_z3".
  1125 
  1126 * Added basic SMT support for datatypes, records, and typedefs using
  1127 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1128 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1129 support for a similar behavior).  Minor INCOMPATIBILITY.
  1130 
  1131 * Changed SMT configuration options:
  1132   - Renamed:
  1133     z3_proofs ~> smt_oracle (with inverted meaning)
  1134     z3_trace_assms ~> smt_trace_used_facts
  1135     INCOMPATIBILITY.
  1136   - Added:
  1137     smt_verbose
  1138     smt_random_seed
  1139     smt_datatypes
  1140     smt_infer_triggers
  1141     smt_monomorph_limit
  1142     cvc3_options
  1143     remote_cvc3_options
  1144     remote_z3_options
  1145     yices_options
  1146 
  1147 * Boogie output files (.b2i files) need to be declared in the theory
  1148 header.
  1149 
  1150 * Simplification procedure "list_to_set_comprehension" rewrites list
  1151 comprehensions applied to List.set to set comprehensions.  Occasional
  1152 INCOMPATIBILITY, may be deactivated like this:
  1153 
  1154   declare [[simproc del: list_to_set_comprehension]]
  1155 
  1156 * Removed old version of primrec package.  INCOMPATIBILITY.
  1157 
  1158 * Removed simplifier congruence rule of "prod_case", as has for long
  1159 been the case with "split".  INCOMPATIBILITY.
  1160 
  1161 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1162 
  1163 * Removed [split_format ... and ... and ...] version of
  1164 [split_format].  Potential INCOMPATIBILITY.
  1165 
  1166 * Predicate "sorted" now defined inductively, with nice induction
  1167 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1168 
  1169 * Constant "contents" renamed to "the_elem", to free the generic name
  1170 contents for other uses.  INCOMPATIBILITY.
  1171 
  1172 * Renamed class eq and constant eq (for code generation) to class
  1173 equal and constant equal, plus renaming of related facts and various
  1174 tuning.  INCOMPATIBILITY.
  1175 
  1176 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1177 
  1178 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1179 INCOMPATIBILITY.
  1180 
  1181 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1182 avoid confusion with finite sets.  INCOMPATIBILITY.
  1183 
  1184 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1185 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1186 for congruent(2)).
  1187 
  1188 * Some previously unqualified names have been qualified:
  1189 
  1190   types
  1191     bool ~> HOL.bool
  1192     nat ~> Nat.nat
  1193 
  1194   constants
  1195     Trueprop ~> HOL.Trueprop
  1196     True ~> HOL.True
  1197     False ~> HOL.False
  1198     op & ~> HOL.conj
  1199     op | ~> HOL.disj
  1200     op --> ~> HOL.implies
  1201     op = ~> HOL.eq
  1202     Not ~> HOL.Not
  1203     The ~> HOL.The
  1204     All ~> HOL.All
  1205     Ex ~> HOL.Ex
  1206     Ex1 ~> HOL.Ex1
  1207     Let ~> HOL.Let
  1208     If ~> HOL.If
  1209     Ball ~> Set.Ball
  1210     Bex ~> Set.Bex
  1211     Suc ~> Nat.Suc
  1212     Pair ~> Product_Type.Pair
  1213     fst ~> Product_Type.fst
  1214     snd ~> Product_Type.snd
  1215     curry ~> Product_Type.curry
  1216     op : ~> Set.member
  1217     Collect ~> Set.Collect
  1218 
  1219 INCOMPATIBILITY.
  1220 
  1221 * More canonical naming convention for some fundamental definitions:
  1222 
  1223     bot_bool_eq ~> bot_bool_def
  1224     top_bool_eq ~> top_bool_def
  1225     inf_bool_eq ~> inf_bool_def
  1226     sup_bool_eq ~> sup_bool_def
  1227     bot_fun_eq  ~> bot_fun_def
  1228     top_fun_eq  ~> top_fun_def
  1229     inf_fun_eq  ~> inf_fun_def
  1230     sup_fun_eq  ~> sup_fun_def
  1231 
  1232 INCOMPATIBILITY.
  1233 
  1234 * More stylized fact names:
  1235 
  1236   expand_fun_eq ~> fun_eq_iff
  1237   expand_set_eq ~> set_eq_iff
  1238   set_ext       ~> set_eqI
  1239   nat_number    ~> eval_nat_numeral
  1240 
  1241 INCOMPATIBILITY.
  1242 
  1243 * Refactoring of code-generation specific operations in theory List:
  1244 
  1245   constants
  1246     null ~> List.null
  1247 
  1248   facts
  1249     mem_iff ~> member_def
  1250     null_empty ~> null_def
  1251 
  1252 INCOMPATIBILITY.  Note that these were not supposed to be used
  1253 regularly unless for striking reasons; their main purpose was code
  1254 generation.
  1255 
  1256 Various operations from the Haskell prelude are used for generating
  1257 Haskell code.
  1258 
  1259 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1260 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1261 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1262 
  1263 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1264 "*" and "+" respectively.  INCOMPATIBILITY.
  1265 
  1266 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1267 "Sum_Type.Plus" instead.
  1268 
  1269 * Constant "split" has been merged with constant "prod_case"; names of
  1270 ML functions, facts etc. involving split have been retained so far,
  1271 though.  INCOMPATIBILITY.
  1272 
  1273 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1274 instead.  INCOMPATIBILITY.
  1275 
  1276 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1277 INCOMPATIBILITY.
  1278 
  1279 * Former theory Library/Enum is now part of the HOL-Main image.
  1280 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1281 referred to by its qualified name.
  1282 
  1283   enum    ~>  Enum.enum
  1284   nlists  ~>  Enum.nlists
  1285   product ~>  Enum.product
  1286 
  1287 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1288 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1289 INCOMPATIBILITY.
  1290 
  1291 * Theory Library/SetsAndFunctions has been split into
  1292 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1293 for instance definitions for functions; various improvements.
  1294 INCOMPATIBILITY.
  1295 
  1296 * Theory Library/Multiset provides stable quicksort implementation of
  1297 sort_key.
  1298 
  1299 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1300 INCOMPATIBILITY.
  1301 
  1302 * Session Multivariate_Analysis: introduced a type class for euclidean
  1303 space.  Most theorems are now stated in terms of euclidean spaces
  1304 instead of finite cartesian products.
  1305 
  1306   types
  1307     real ^ 'n ~>  'a::real_vector
  1308               ~>  'a::euclidean_space
  1309               ~>  'a::ordered_euclidean_space
  1310         (depends on your needs)
  1311 
  1312   constants
  1313      _ $ _        ~> _ $$ _
  1314      \<chi> x. _  ~> \<chi>\<chi> x. _
  1315      CARD('n)     ~> DIM('a)
  1316 
  1317 Also note that the indices are now natural numbers and not from some
  1318 finite type. Finite cartesian products of euclidean spaces, products
  1319 of euclidean spaces the real and complex numbers are instantiated to
  1320 be euclidean_spaces.  INCOMPATIBILITY.
  1321 
  1322 * Session Probability: introduced pextreal as positive extended real
  1323 numbers.  Use pextreal as value for measures.  Introduce the
  1324 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1325 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1326 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1327 
  1328 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1329 INCOMPATIBILITY.
  1330 
  1331 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1332 prove verification conditions generated by the SPARK Ada program
  1333 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1334 
  1335 
  1336 *** HOL-Algebra ***
  1337 
  1338 * Theorems for additive ring operations (locale abelian_monoid and
  1339 descendants) are generated by interpretation from their multiplicative
  1340 counterparts.  Names (in particular theorem names) have the mandatory
  1341 qualifier 'add'.  Previous theorem names are redeclared for
  1342 compatibility.
  1343 
  1344 * Structure "int_ring" is now an abbreviation (previously a
  1345 definition).  This fits more natural with advanced interpretations.
  1346 
  1347 
  1348 *** HOLCF ***
  1349 
  1350 * The domain package now runs in definitional mode by default: The
  1351 former command 'new_domain' is now called 'domain'.  To use the domain
  1352 package in its original axiomatic mode, use 'domain (unsafe)'.
  1353 INCOMPATIBILITY.
  1354 
  1355 * The new class "domain" is now the default sort.  Class "predomain"
  1356 is an unpointed version of "domain". Theories can be updated by
  1357 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1358 
  1359   'a::type ~> 'a::countable
  1360   'a::cpo  ~> 'a::predomain
  1361   'a::pcpo ~> 'a::domain
  1362 
  1363 * The old type class "rep" has been superseded by class "domain".
  1364 Accordingly, users of the definitional package must remove any
  1365 "default_sort rep" declarations.  INCOMPATIBILITY.
  1366 
  1367 * The domain package (definitional mode) now supports unpointed
  1368 predomain argument types, as long as they are marked 'lazy'. (Strict
  1369 arguments must be in class "domain".) For example, the following
  1370 domain definition now works:
  1371 
  1372   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1373 
  1374 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1375 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1376 'a option, and 'a list.  Additionally, it configures fixrec and the
  1377 domain package to work with these types.  For example:
  1378 
  1379   fixrec isInl :: "('a + 'b) u -> tr"
  1380     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1381 
  1382   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1383 
  1384 * The "(permissive)" option of fixrec has been replaced with a
  1385 per-equation "(unchecked)" option. See
  1386 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1387 
  1388 * The "bifinite" class no longer fixes a constant "approx"; the class
  1389 now just asserts that such a function exists.  INCOMPATIBILITY.
  1390 
  1391 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1392 defines an embedding of type 'a defl into udom by default; instances
  1393 of "bifinite" and "domain" classes are available in
  1394 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1395 
  1396 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1397 
  1398 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1399 
  1400 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1401 
  1402 * The function "cprod_map" has been renamed to "prod_map".
  1403 INCOMPATIBILITY.
  1404 
  1405 * The monadic bind operator on each powerdomain has new binder syntax
  1406 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1407 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1408 
  1409 * The infix syntax for binary union on each powerdomain has changed
  1410 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1411 syntax.  INCOMPATIBILITY.
  1412 
  1413 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1414 still supported as an input translation.
  1415 
  1416 * Renamed some theorems (the original names are also still available).
  1417 
  1418   expand_fun_below   ~> fun_below_iff
  1419   below_fun_ext      ~> fun_belowI
  1420   expand_cfun_eq     ~> cfun_eq_iff
  1421   ext_cfun           ~> cfun_eqI
  1422   expand_cfun_below  ~> cfun_below_iff
  1423   below_cfun_ext     ~> cfun_belowI
  1424   cont2cont_Rep_CFun ~> cont2cont_APP
  1425 
  1426 * The Abs and Rep functions for various types have changed names.
  1427 Related theorem names have also changed to match. INCOMPATIBILITY.
  1428 
  1429   Rep_CFun  ~> Rep_cfun
  1430   Abs_CFun  ~> Abs_cfun
  1431   Rep_Sprod ~> Rep_sprod
  1432   Abs_Sprod ~> Abs_sprod
  1433   Rep_Ssum  ~> Rep_ssum
  1434   Abs_Ssum  ~> Abs_ssum
  1435 
  1436 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1437 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1438 
  1439 * Various changes to bisimulation/coinduction with domain package:
  1440 
  1441   - Definitions of "bisim" constants no longer mention definedness.
  1442   - With mutual recursion, "bisim" predicate is now curried.
  1443   - With mutual recursion, each type gets a separate coind theorem.
  1444   - Variable names in bisim_def and coinduct rules have changed.
  1445 
  1446 INCOMPATIBILITY.
  1447 
  1448 * Case combinators generated by the domain package for type "foo" are
  1449 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1450 
  1451 * Several theorems have been renamed to more accurately reflect the
  1452 names of constants and types involved.  INCOMPATIBILITY.
  1453 
  1454   thelub_const    ~> lub_const
  1455   lub_const       ~> is_lub_const
  1456   thelubI         ~> lub_eqI
  1457   is_lub_lub      ~> is_lubD2
  1458   lubI            ~> is_lub_lub
  1459   unique_lub      ~> is_lub_unique
  1460   is_ub_lub       ~> is_lub_rangeD1
  1461   lub_bin_chain   ~> is_lub_bin_chain
  1462   lub_fun         ~> is_lub_fun
  1463   thelub_fun      ~> lub_fun
  1464   thelub_cfun     ~> lub_cfun
  1465   thelub_Pair     ~> lub_Pair
  1466   lub_cprod       ~> is_lub_prod
  1467   thelub_cprod    ~> lub_prod
  1468   minimal_cprod   ~> minimal_prod
  1469   inst_cprod_pcpo ~> inst_prod_pcpo
  1470   UU_I            ~> bottomI
  1471   compact_UU      ~> compact_bottom
  1472   deflation_UU    ~> deflation_bottom
  1473   finite_deflation_UU ~> finite_deflation_bottom
  1474 
  1475 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1476 
  1477   sq_ord_less_eq_trans ~> below_eq_trans
  1478   sq_ord_eq_less_trans ~> eq_below_trans
  1479   refl_less            ~> below_refl
  1480   trans_less           ~> below_trans
  1481   antisym_less         ~> below_antisym
  1482   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1483   box_less             ~> box_below
  1484   rev_trans_less       ~> rev_below_trans
  1485   not_less2not_eq      ~> not_below2not_eq
  1486   less_UU_iff          ~> below_UU_iff
  1487   flat_less_iff        ~> flat_below_iff
  1488   adm_less             ~> adm_below
  1489   adm_not_less         ~> adm_not_below
  1490   adm_compact_not_less ~> adm_compact_not_below
  1491   less_fun_def         ~> below_fun_def
  1492   expand_fun_less      ~> fun_below_iff
  1493   less_fun_ext         ~> fun_belowI
  1494   less_discr_def       ~> below_discr_def
  1495   discr_less_eq        ~> discr_below_eq
  1496   less_unit_def        ~> below_unit_def
  1497   less_cprod_def       ~> below_prod_def
  1498   prod_lessI           ~> prod_belowI
  1499   Pair_less_iff        ~> Pair_below_iff
  1500   fst_less_iff         ~> fst_below_iff
  1501   snd_less_iff         ~> snd_below_iff
  1502   expand_cfun_less     ~> cfun_below_iff
  1503   less_cfun_ext        ~> cfun_belowI
  1504   injection_less       ~> injection_below
  1505   less_up_def          ~> below_up_def
  1506   not_Iup_less         ~> not_Iup_below
  1507   Iup_less             ~> Iup_below
  1508   up_less              ~> up_below
  1509   Def_inject_less_eq   ~> Def_below_Def
  1510   Def_less_is_eq       ~> Def_below_iff
  1511   spair_less_iff       ~> spair_below_iff
  1512   less_sprod           ~> below_sprod
  1513   spair_less           ~> spair_below
  1514   sfst_less_iff        ~> sfst_below_iff
  1515   ssnd_less_iff        ~> ssnd_below_iff
  1516   fix_least_less       ~> fix_least_below
  1517   dist_less_one        ~> dist_below_one
  1518   less_ONE             ~> below_ONE
  1519   ONE_less_iff         ~> ONE_below_iff
  1520   less_sinlD           ~> below_sinlD
  1521   less_sinrD           ~> below_sinrD
  1522 
  1523 
  1524 *** FOL and ZF ***
  1525 
  1526 * All constant names are now qualified internally and use proper
  1527 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1528 
  1529 
  1530 *** ML ***
  1531 
  1532 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1533 Fail if the argument is false.  Due to inlining the source position of
  1534 failed assertions is included in the error output.
  1535 
  1536 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1537 text is in practice always evaluated with a stable theory checkpoint.
  1538 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1539 
  1540 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1541 the current context, not any accidental theory loader state as before.
  1542 Potential INCOMPATIBILITY, subtle change in semantics.
  1543 
  1544 * Syntax.pretty_priority (default 0) configures the required priority
  1545 of pretty-printed output and thus affects insertion of parentheses.
  1546 
  1547 * Syntax.default_root (default "any") configures the inner syntax
  1548 category (nonterminal symbol) for parsing of terms.
  1549 
  1550 * Former exception Library.UnequalLengths now coincides with
  1551 ListPair.UnequalLengths.
  1552 
  1553 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1554 main functionality is provided by structure Simplifier.
  1555 
  1556 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1557 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1558 almost all situations.
  1559 
  1560 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1561 See implementation manual for further details on exceptions in
  1562 Isabelle/ML.
  1563 
  1564 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1565 meaning.
  1566 
  1567 * Renamed structure PureThy to Pure_Thy and moved most of its
  1568 operations to structure Global_Theory, to emphasize that this is
  1569 rarely-used global-only stuff.
  1570 
  1571 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1572 instead (or tracing for high-volume output).
  1573 
  1574 * Configuration option show_question_marks only affects regular pretty
  1575 printing of types and terms, not raw Term.string_of_vname.
  1576 
  1577 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1578 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1579 @{thms} for most purposes.
  1580 
  1581 * ML structure Unsynchronized is never opened, not even in Isar
  1582 interaction mode as before.  Old Unsynchronized.set etc. have been
  1583 discontinued -- use plain := instead.  This should be *rare* anyway,
  1584 since modern tools always work via official context data, notably
  1585 configuration options.
  1586 
  1587 * Parallel and asynchronous execution requires special care concerning
  1588 interrupts.  Structure Exn provides some convenience functions that
  1589 avoid working directly with raw Interrupt.  User code must not absorb
  1590 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1591 followed by re-raising of the original exception.  Another common
  1592 source of mistakes are "handle _" patterns, which make the meaning of
  1593 the program subject to physical effects of the environment.
  1594 
  1595 
  1596 
  1597 New in Isabelle2009-2 (June 2010)
  1598 ---------------------------------
  1599 
  1600 *** General ***
  1601 
  1602 * Authentic syntax for *all* logical entities (type classes, type
  1603 constructors, term constants): provides simple and robust
  1604 correspondence between formal entities and concrete syntax.  Within
  1605 the parse tree / AST representations, "constants" are decorated by
  1606 their category (class, type, const) and spelled out explicitly with
  1607 their full internal name.
  1608 
  1609 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1610 and translations (translation rules and translation functions in ML).
  1611 Some hints on upgrading:
  1612 
  1613   - Many existing uses of 'syntax' and 'translations' can be replaced
  1614     by more modern 'type_notation', 'notation' and 'abbreviation',
  1615     which are independent of this issue.
  1616 
  1617   - 'translations' require markup within the AST; the term syntax
  1618     provides the following special forms:
  1619 
  1620       CONST c   -- produces syntax version of constant c from context
  1621       XCONST c  -- literally c, checked as constant from context
  1622       c         -- literally c, if declared by 'syntax'
  1623 
  1624     Plain identifiers are treated as AST variables -- occasionally the
  1625     system indicates accidental variables via the error "rhs contains
  1626     extra variables".
  1627 
  1628     Type classes and type constructors are marked according to their
  1629     concrete syntax.  Some old translations rules need to be written
  1630     for the "type" category, using type constructor application
  1631     instead of pseudo-term application of the default category
  1632     "logic".
  1633 
  1634   - 'parse_translation' etc. in ML may use the following
  1635     antiquotations:
  1636 
  1637       @{class_syntax c}   -- type class c within parse tree / AST
  1638       @{term_syntax c}    -- type constructor c within parse tree / AST
  1639       @{const_syntax c}   -- ML version of "CONST c" above
  1640       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1641 
  1642   - Literal types within 'typed_print_translations', i.e. those *not*
  1643     represented as pseudo-terms are represented verbatim.  Use @{class
  1644     c} or @{type_name c} here instead of the above syntax
  1645     antiquotations.
  1646 
  1647 Note that old non-authentic syntax was based on unqualified base
  1648 names, so all of the above "constant" names would coincide.  Recall
  1649 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1650 diagnose syntax problems.
  1651 
  1652 * Type constructors admit general mixfix syntax, not just infix.
  1653 
  1654 * Concrete syntax may be attached to local entities without a proof
  1655 body, too.  This works via regular mixfix annotations for 'fix',
  1656 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1657 similar to the 'notation' command in theory specifications.
  1658 
  1659 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1660 need to specify constant name and syntax separately.  Internal ML
  1661 datatype constructors have been renamed from InfixName to Infix etc.
  1662 Minor INCOMPATIBILITY.
  1663 
  1664 * Schematic theorem statements need to be explicitly markup as such,
  1665 via commands 'schematic_lemma', 'schematic_theorem',
  1666 'schematic_corollary'.  Thus the relevance of the proof is made
  1667 syntactically clear, which impacts performance in a parallel or
  1668 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1669 
  1670 * Use of cumulative prems via "!" in some proof methods has been
  1671 discontinued (old legacy feature).
  1672 
  1673 * References 'trace_simp' and 'debug_simp' have been replaced by
  1674 configuration options stored in the context. Enabling tracing (the
  1675 case of debugging is similar) in proofs works via
  1676 
  1677   using [[trace_simp = true]]
  1678 
  1679 Tracing is then active for all invocations of the simplifier in
  1680 subsequent goal refinement steps. Tracing may also still be enabled or
  1681 disabled via the ProofGeneral settings menu.
  1682 
  1683 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1684 'hide_fact' replace the former 'hide' KIND command.  Minor
  1685 INCOMPATIBILITY.
  1686 
  1687 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1688 more efficient than combinations with -q1 or -q2.
  1689 
  1690 
  1691 *** Pure ***
  1692 
  1693 * Proofterms record type-class reasoning explicitly, using the
  1694 "unconstrain" operation internally.  This eliminates all sort
  1695 constraints from a theorem and proof, introducing explicit
  1696 OFCLASS-premises.  On the proof term level, this operation is
  1697 automatically applied at theorem boundaries, such that closed proofs
  1698 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1699 inspect proof terms.
  1700 
  1701 * Local theory specifications may depend on extra type variables that
  1702 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1703 are added internally.  For example:
  1704 
  1705   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1706 
  1707 * Predicates of locales introduced by classes carry a mandatory
  1708 "class" prefix.  INCOMPATIBILITY.
  1709 
  1710 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1711 
  1712 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1713 'class' instead.
  1714 
  1715 * Command 'code_reflect' allows to incorporate generated ML code into
  1716 runtime environment; replaces immature code_datatype antiquotation.
  1717 INCOMPATIBILITY.
  1718 
  1719 * Code generator: simple concept for abstract datatypes obeying
  1720 invariants.
  1721 
  1722 * Code generator: details of internal data cache have no impact on the
  1723 user space functionality any longer.
  1724 
  1725 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1726 subgoals.  This is more appropriate for interpretations with 'where'.
  1727 INCOMPATIBILITY.
  1728 
  1729 * Command 'example_proof' opens an empty proof body.  This allows to
  1730 experiment with Isar, without producing any persistent result.
  1731 
  1732 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1733 within a local theory context, with explicit checking of the
  1734 constructors involved (in contrast to the raw 'syntax' versions).
  1735 
  1736 * Commands 'types' and 'typedecl' now work within a local theory
  1737 context -- without introducing dependencies on parameters or
  1738 assumptions, which is not possible in Isabelle/Pure.
  1739 
  1740 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1741 within a local theory context.  Minor INCOMPATIBILITY.
  1742 
  1743 
  1744 *** HOL ***
  1745 
  1746 * Command 'typedef' now works within a local theory context -- without
  1747 introducing dependencies on parameters or assumptions, which is not
  1748 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1749 contain multiple interpretations of local typedefs (with different
  1750 non-emptiness proofs), even in a global theory context.
  1751 
  1752 * New package for quotient types.  Commands 'quotient_type' and
  1753 'quotient_definition' may be used for defining types and constants by
  1754 quotient constructions.  An example is the type of integers created by
  1755 quotienting pairs of natural numbers:
  1756 
  1757   fun
  1758     intrel :: "(nat * nat) => (nat * nat) => bool"
  1759   where
  1760     "intrel (x, y) (u, v) = (x + v = u + y)"
  1761 
  1762   quotient_type int = "nat * nat" / intrel
  1763     by (auto simp add: equivp_def expand_fun_eq)
  1764 
  1765   quotient_definition
  1766     "0::int" is "(0::nat, 0::nat)"
  1767 
  1768 The method "lifting" can be used to lift of theorems from the
  1769 underlying "raw" type to the quotient type.  The example
  1770 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1771 construction and provides a reasoning infrastructure for finite sets.
  1772 
  1773 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1774 clash with new theory Quotient in Main HOL.
  1775 
  1776 * Moved the SMT binding into the main HOL session, eliminating
  1777 separate HOL-SMT session.
  1778 
  1779 * List membership infix mem operation is only an input abbreviation.
  1780 INCOMPATIBILITY.
  1781 
  1782 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1783 for future developements; former Library/Word.thy is still present in
  1784 the AFP entry RSAPPS.
  1785 
  1786 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1787 longer shadowed.  INCOMPATIBILITY.
  1788 
  1789 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1790 INCOMPATIBILITY.
  1791 
  1792 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1793 INCOMPATIBILITY.
  1794 
  1795 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1796 instead.  INCOMPATIBILITY.
  1797 
  1798 * Dropped several real-specific versions of lemmas about floor and
  1799 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1800 instead.  INCOMPATIBILITY.
  1801 
  1802   floor_number_of_eq         ~> floor_number_of
  1803   le_floor_eq_number_of      ~> number_of_le_floor
  1804   le_floor_eq_zero           ~> zero_le_floor
  1805   le_floor_eq_one            ~> one_le_floor
  1806   floor_less_eq_number_of    ~> floor_less_number_of
  1807   floor_less_eq_zero         ~> floor_less_zero
  1808   floor_less_eq_one          ~> floor_less_one
  1809   less_floor_eq_number_of    ~> number_of_less_floor
  1810   less_floor_eq_zero         ~> zero_less_floor
  1811   less_floor_eq_one          ~> one_less_floor
  1812   floor_le_eq_number_of      ~> floor_le_number_of
  1813   floor_le_eq_zero           ~> floor_le_zero
  1814   floor_le_eq_one            ~> floor_le_one
  1815   floor_subtract_number_of   ~> floor_diff_number_of
  1816   floor_subtract_one         ~> floor_diff_one
  1817   ceiling_number_of_eq       ~> ceiling_number_of
  1818   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1819   ceiling_le_zero_eq         ~> ceiling_le_zero
  1820   ceiling_le_eq_one          ~> ceiling_le_one
  1821   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1822   less_ceiling_eq_zero       ~> zero_less_ceiling
  1823   less_ceiling_eq_one        ~> one_less_ceiling
  1824   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1825   ceiling_less_eq_zero       ~> ceiling_less_zero
  1826   ceiling_less_eq_one        ~> ceiling_less_one
  1827   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1828   le_ceiling_eq_zero         ~> zero_le_ceiling
  1829   le_ceiling_eq_one          ~> one_le_ceiling
  1830   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1831   ceiling_subtract_one       ~> ceiling_diff_one
  1832 
  1833 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1834 application of the various fold combinators on finite sets.
  1835 
  1836 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1837 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1838 implementation.  INCOMPATIBILTY.
  1839 
  1840 * Theory Library/Coinductive_List has been removed -- superseded by
  1841 AFP/thys/Coinductive.
  1842 
  1843 * Theory PReal, including the type "preal" and related operations, has
  1844 been removed.  INCOMPATIBILITY.
  1845 
  1846 * Real: new development using Cauchy Sequences.
  1847 
  1848 * Split off theory "Big_Operators" containing setsum, setprod,
  1849 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1850 
  1851 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1852 "Int" etc.  INCOMPATIBILITY.
  1853 
  1854 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1855 
  1856 * New set of rules "ac_simps" provides combined assoc / commute
  1857 rewrites for all interpretations of the appropriate generic locales.
  1858 
  1859 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1860 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1861 appropriate and more consistent names suitable for name prefixes
  1862 within the HOL theories.  INCOMPATIBILITY.
  1863 
  1864 * Some generic constants have been put to appropriate theories:
  1865   - less_eq, less: Orderings
  1866   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1867   - inverse, divide: Rings
  1868 INCOMPATIBILITY.
  1869 
  1870 * More consistent naming of type classes involving orderings (and
  1871 lattices):
  1872 
  1873     lower_semilattice                   ~> semilattice_inf
  1874     upper_semilattice                   ~> semilattice_sup
  1875 
  1876     dense_linear_order                  ~> dense_linorder
  1877 
  1878     pordered_ab_group_add               ~> ordered_ab_group_add
  1879     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1880     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1881     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1882     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1883     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1884     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1885     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1886     pordered_comm_ring                  ~> ordered_comm_ring
  1887     pordered_comm_semiring              ~> ordered_comm_semiring
  1888     pordered_ring                       ~> ordered_ring
  1889     pordered_ring_abs                   ~> ordered_ring_abs
  1890     pordered_semiring                   ~> ordered_semiring
  1891 
  1892     ordered_ab_group_add                ~> linordered_ab_group_add
  1893     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1894     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1895     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1896     ordered_field                       ~> linordered_field
  1897     ordered_field_no_lb                 ~> linordered_field_no_lb
  1898     ordered_field_no_ub                 ~> linordered_field_no_ub
  1899     ordered_field_dense_linear_order    ~> dense_linordered_field
  1900     ordered_idom                        ~> linordered_idom
  1901     ordered_ring                        ~> linordered_ring
  1902     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1903     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1904     ordered_ring_strict                 ~> linordered_ring_strict
  1905     ordered_semidom                     ~> linordered_semidom
  1906     ordered_semiring                    ~> linordered_semiring
  1907     ordered_semiring_1                  ~> linordered_semiring_1
  1908     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1909     ordered_semiring_strict             ~> linordered_semiring_strict
  1910 
  1911   The following slightly odd type classes have been moved to a
  1912   separate theory Library/Lattice_Algebras:
  1913 
  1914     lordered_ab_group_add               ~> lattice_ab_group_add
  1915     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1916     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1917     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1918     lordered_ring                       ~> lattice_ring
  1919 
  1920 INCOMPATIBILITY.
  1921 
  1922 * Refined field classes:
  1923   - classes division_ring_inverse_zero, field_inverse_zero,
  1924     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1925     subsumes former division_by_zero class;
  1926   - numerous lemmas have been ported from field to division_ring.
  1927 INCOMPATIBILITY.
  1928 
  1929 * Refined algebra theorem collections:
  1930   - dropped theorem group group_simps, use algebra_simps instead;
  1931   - dropped theorem group ring_simps, use field_simps instead;
  1932   - proper theorem collection field_simps subsumes former theorem
  1933     groups field_eq_simps and field_simps;
  1934   - dropped lemma eq_minus_self_iff which is a duplicate for
  1935     equal_neg_zero.
  1936 INCOMPATIBILITY.
  1937 
  1938 * Theory Finite_Set and List: some lemmas have been generalized from
  1939 sets to lattices:
  1940 
  1941   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1942   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1943   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1944   union_Union_fold_union        ~> sup_Sup_fold_sup
  1945   Inter_fold_inter              ~> Inf_fold_inf
  1946   Union_fold_union              ~> Sup_fold_sup
  1947   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1948   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1949   INTER_fold_inter              ~> INFI_fold_inf
  1950   UNION_fold_union              ~> SUPR_fold_sup
  1951 
  1952 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1953 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1954 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1955 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1956 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1957 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1958 
  1959 * Reorganized theory Multiset: swapped notation of pointwise and
  1960 multiset order:
  1961 
  1962   - pointwise ordering is instance of class order with standard syntax
  1963     <= and <;
  1964   - multiset ordering has syntax <=# and <#; partial order properties
  1965     are provided by means of interpretation with prefix
  1966     multiset_order;
  1967   - less duplication, less historical organization of sections,
  1968     conversion from associations lists to multisets, rudimentary code
  1969     generation;
  1970   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1971     if needed.
  1972 
  1973 Renamed:
  1974 
  1975   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1976   multi_count_ext  ~>  multiset_ext
  1977   diff_union_inverse2  ~>  diff_union_cancelR
  1978 
  1979 INCOMPATIBILITY.
  1980 
  1981 * Theory Permutation: replaced local "remove" by List.remove1.
  1982 
  1983 * Code generation: ML and OCaml code is decorated with signatures.
  1984 
  1985 * Theory List: added transpose.
  1986 
  1987 * Library/Nat_Bijection.thy is a collection of bijective functions
  1988 between nat and other types, which supersedes the older libraries
  1989 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1990 
  1991   Constants:
  1992   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1993   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1994   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1995   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1996   Countable.pair_encode           ~> prod_encode
  1997   NatIso.prod2nat                 ~> prod_encode
  1998   NatIso.nat2prod                 ~> prod_decode
  1999   NatIso.sum2nat                  ~> sum_encode
  2000   NatIso.nat2sum                  ~> sum_decode
  2001   NatIso.list2nat                 ~> list_encode
  2002   NatIso.nat2list                 ~> list_decode
  2003   NatIso.set2nat                  ~> set_encode
  2004   NatIso.nat2set                  ~> set_decode
  2005 
  2006   Lemmas:
  2007   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  2008   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  2009   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  2010   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  2011   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  2012   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  2013   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  2014   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  2015   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  2016   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  2017   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  2018   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  2019   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  2020 
  2021 * Sledgehammer:
  2022   - Renamed ATP commands:
  2023     atp_info     ~> sledgehammer running_atps
  2024     atp_kill     ~> sledgehammer kill_atps
  2025     atp_messages ~> sledgehammer messages
  2026     atp_minimize ~> sledgehammer minimize
  2027     print_atps   ~> sledgehammer available_atps
  2028     INCOMPATIBILITY.
  2029   - Added user's manual ("isabelle doc sledgehammer").
  2030   - Added option syntax and "sledgehammer_params" to customize
  2031     Sledgehammer's behavior.  See the manual for details.
  2032   - Modified the Isar proof reconstruction code so that it produces
  2033     direct proofs rather than proofs by contradiction.  (This feature
  2034     is still experimental.)
  2035   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  2036     full-typed mode.
  2037   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  2038 
  2039 * Nitpick:
  2040   - Added and implemented "binary_ints" and "bits" options.
  2041   - Added "std" option and implemented support for nonstandard models.
  2042   - Added and implemented "finitize" option to improve the precision
  2043     of infinite datatypes based on a monotonicity analysis.
  2044   - Added support for quotient types.
  2045   - Added support for "specification" and "ax_specification"
  2046     constructs.
  2047   - Added support for local definitions (for "function" and
  2048     "termination" proofs).
  2049   - Added support for term postprocessors.
  2050   - Optimized "Multiset.multiset" and "FinFun.finfun".
  2051   - Improved efficiency of "destroy_constrs" optimization.
  2052   - Fixed soundness bugs related to "destroy_constrs" optimization and
  2053     record getters.
  2054   - Fixed soundness bug related to higher-order constructors.
  2055   - Fixed soundness bug when "full_descrs" is enabled.
  2056   - Improved precision of set constructs.
  2057   - Added "atoms" option.
  2058   - Added cache to speed up repeated Kodkod invocations on the same
  2059     problems.
  2060   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  2061     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  2062     "SAT4J_Light".  INCOMPATIBILITY.
  2063   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  2064     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  2065   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  2066 
  2067 * Method "induct" now takes instantiations of the form t, where t is not
  2068   a variable, as a shorthand for "x == t", where x is a fresh variable.
  2069   If this is not intended, t has to be enclosed in parentheses.
  2070   By default, the equalities generated by definitional instantiations
  2071   are pre-simplified, which may cause parameters of inductive cases
  2072   to disappear, or may even delete some of the inductive cases.
  2073   Use "induct (no_simp)" instead of "induct" to restore the old
  2074   behaviour. The (no_simp) option is also understood by the "cases"
  2075   and "nominal_induct" methods, which now perform pre-simplification, too.
  2076   INCOMPATIBILITY.
  2077 
  2078 
  2079 *** HOLCF ***
  2080 
  2081 * Variable names in lemmas generated by the domain package have
  2082 changed; the naming scheme is now consistent with the HOL datatype
  2083 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  2084 
  2085 * The domain package no longer defines the function "foo_copy" for
  2086 recursive domain "foo".  The reach lemma is now stated directly in
  2087 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  2088 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  2089 
  2090 * Most definedness lemmas generated by the domain package (previously
  2091 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  2092 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  2093 Proofs that used definedness lemmas as intro rules may break,
  2094 potential INCOMPATIBILITY.
  2095 
  2096 * Induction and casedist rules generated by the domain package now
  2097 declare proper case_names (one called "bottom", and one named for each
  2098 constructor).  INCOMPATIBILITY.
  2099 
  2100 * For mutually-recursive domains, separate "reach" and "take_lemma"
  2101 rules are generated for each domain, INCOMPATIBILITY.
  2102 
  2103   foo_bar.reach       ~> foo.reach  bar.reach
  2104   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  2105 
  2106 * Some lemmas generated by the domain package have been renamed for
  2107 consistency with the datatype package, INCOMPATIBILITY.
  2108 
  2109   foo.ind        ~> foo.induct
  2110   foo.finite_ind ~> foo.finite_induct
  2111   foo.coind      ~> foo.coinduct
  2112   foo.casedist   ~> foo.exhaust
  2113   foo.exhaust    ~> foo.nchotomy
  2114 
  2115 * For consistency with other definition packages, the fixrec package
  2116 now generates qualified theorem names, INCOMPATIBILITY.
  2117 
  2118   foo_simps  ~> foo.simps
  2119   foo_unfold ~> foo.unfold
  2120   foo_induct ~> foo.induct
  2121 
  2122 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2123 method and internal fixrec proofs now use the default simpset instead.
  2124 INCOMPATIBILITY.
  2125 
  2126 * The "contlub" predicate has been removed.  Proof scripts should use
  2127 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2128 
  2129 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2130 
  2131 * The constants cpair, cfst, and csnd have been removed in favor of
  2132 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2133 
  2134 
  2135 *** ML ***
  2136 
  2137 * Antiquotations for basic formal entities:
  2138 
  2139     @{class NAME}         -- type class
  2140     @{class_syntax NAME}  -- syntax representation of the above
  2141 
  2142     @{type_name NAME}     -- logical type
  2143     @{type_abbrev NAME}   -- type abbreviation
  2144     @{nonterminal NAME}   -- type of concrete syntactic category
  2145     @{type_syntax NAME}   -- syntax representation of any of the above
  2146 
  2147     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2148     @{const_abbrev NAME}  -- abbreviated constant
  2149     @{const_syntax NAME}  -- syntax representation of any of the above
  2150 
  2151 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2152 syntax constant (cf. 'syntax' command).
  2153 
  2154 * Antiquotation @{make_string} inlines a function to print arbitrary
  2155 values similar to the ML toplevel.  The result is compiler dependent
  2156 and may fall back on "?" in certain situations.
  2157 
  2158 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2159 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2160 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2161 not work with the asynchronous Isar document model.
  2162 
  2163 * Configuration options now admit dynamic default values, depending on
  2164 the context or even global references.
  2165 
  2166 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2167 uses an efficient external library if available (for Poly/ML).
  2168 
  2169 * Renamed some important ML structures, while keeping the old names
  2170 for some time as aliases within the structure Legacy:
  2171 
  2172   OuterKeyword  ~>  Keyword
  2173   OuterLex      ~>  Token
  2174   OuterParse    ~>  Parse
  2175   OuterSyntax   ~>  Outer_Syntax
  2176   PrintMode     ~>  Print_Mode
  2177   SpecParse     ~>  Parse_Spec
  2178   ThyInfo       ~>  Thy_Info
  2179   ThyLoad       ~>  Thy_Load
  2180   ThyOutput     ~>  Thy_Output
  2181   TypeInfer     ~>  Type_Infer
  2182 
  2183 Note that "open Legacy" simplifies porting of sources, but forgetting
  2184 to remove it again will complicate porting again in the future.
  2185 
  2186 * Most operations that refer to a global context are named
  2187 accordingly, e.g. Simplifier.global_context or
  2188 ProofContext.init_global.  There are some situations where a global
  2189 context actually works, but under normal circumstances one needs to
  2190 pass the proper local context through the code!
  2191 
  2192 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2193 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2194 Pretty.pp argument to merge, which is absent in the standard
  2195 Theory_Data version.
  2196 
  2197 * Sorts.certify_sort and derived "cert" operations for types and terms
  2198 no longer minimize sorts.  Thus certification at the boundary of the
  2199 inference kernel becomes invariant under addition of class relations,
  2200 which is an important monotonicity principle.  Sorts are now minimized
  2201 in the syntax layer only, at the boundary between the end-user and the
  2202 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2203 explicitly in rare situations.
  2204 
  2205 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2206 emphasize that this is in no way a standard operation.
  2207 INCOMPATIBILITY.
  2208 
  2209 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2210 usual for resolution.  Rare INCOMPATIBILITY.
  2211 
  2212 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2213 to emphasize that these only work in a global situation (which is
  2214 quite rare).
  2215 
  2216 * Curried take and drop in library.ML; negative length is interpreted
  2217 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2218 
  2219 * Proof terms: type substitutions on proof constants now use canonical
  2220 order of type variables.  INCOMPATIBILITY for tools working with proof
  2221 terms.
  2222 
  2223 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2224 may no longer carry premises.  User-level specifications are
  2225 transformed accordingly by Thm.add_axiom/add_def.
  2226 
  2227 
  2228 *** System ***
  2229 
  2230 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2231 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2232 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2233 
  2234 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2235 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2236 respectively.
  2237 
  2238 * Old lib/scripts/polyml-platform is superseded by the
  2239 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2240 variant, even on a 64 bit machine.  The following example setting
  2241 prefers 64 bit if available:
  2242 
  2243   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2244 
  2245 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2246 Isabelle/Scala layer for advanced prover interaction and integration.
  2247 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2248 component.
  2249 
  2250 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2251 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2252 similar to the default assignment of the document preparation system
  2253 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2254 provides some operations for direct access to the font without asking
  2255 the user for manual installation.
  2256 
  2257 
  2258 
  2259 New in Isabelle2009-1 (December 2009)
  2260 -------------------------------------
  2261 
  2262 *** General ***
  2263 
  2264 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2265 one backslash should be used, even in ML sources.
  2266 
  2267 
  2268 *** Pure ***
  2269 
  2270 * Locale interpretation propagates mixins along the locale hierarchy.
  2271 The currently only available mixins are the equations used to map
  2272 local definitions to terms of the target domain of an interpretation.
  2273 
  2274 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2275 loc" to print all interpretations of locale "loc" in the theory.
  2276 Interpretations in proofs are not shown.
  2277 
  2278 * Thoroughly revised locales tutorial.  New section on conditional
  2279 interpretation.
  2280 
  2281 * On instantiation of classes, remaining undefined class parameters
  2282 are formally declared.  INCOMPATIBILITY.
  2283 
  2284 
  2285 *** Document preparation ***
  2286 
  2287 * New generalized style concept for printing terms: @{foo (style) ...}
  2288 instead of @{foo_style style ...}  (old form is still retained for
  2289 backward compatibility).  Styles can be also applied for
  2290 antiquotations prop, term_type and typeof.
  2291 
  2292 
  2293 *** HOL ***
  2294 
  2295 * New proof method "smt" for a combination of first-order logic with
  2296 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2297 fixed-size bitvectors; there is also basic support for higher-order
  2298 features (esp. lambda abstractions).  It is an incomplete decision
  2299 procedure based on external SMT solvers using the oracle mechanism;
  2300 for the SMT solver Z3, this method is proof-producing.  Certificates
  2301 are provided to avoid calling the external solvers solely for
  2302 re-checking proofs.  Due to a remote SMT service there is no need for
  2303 installing SMT solvers locally.  See src/HOL/SMT.
  2304 
  2305 * New commands to load and prove verification conditions generated by
  2306 the Boogie program verifier or derived systems (e.g. the Verifying C
  2307 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2308 
  2309 * New counterexample generator tool 'nitpick' based on the Kodkod
  2310 relational model finder.  See src/HOL/Tools/Nitpick and
  2311 src/HOL/Nitpick_Examples.
  2312 
  2313 * New commands 'code_pred' and 'values' to invoke the predicate
  2314 compiler and to enumerate values of inductive predicates.
  2315 
  2316 * A tabled implementation of the reflexive transitive closure.
  2317 
  2318 * New implementation of quickcheck uses generic code generator;
  2319 default generators are provided for all suitable HOL types, records
  2320 and datatypes.  Old quickcheck can be re-activated importing theory
  2321 Library/SML_Quickcheck.
  2322 
  2323 * New testing tool Mirabelle for automated proof tools.  Applies
  2324 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2325 every proof step in a theory.  To be used in batch mode via the
  2326 "mirabelle" utility.
  2327 
  2328 * New proof method "sos" (sum of squares) for nonlinear real
  2329 arithmetic (originally due to John Harison). It requires theory
  2330 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2331 works well in practice on quantifier-free real arithmetic with +, -,
  2332 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2333 inequalities between polynomials.  It makes use of external
  2334 semidefinite programming solvers.  Method "sos" generates a
  2335 certificate that can be pasted into the proof thus avoiding the need
  2336 to call an external tool every time the proof is checked.  See
  2337 src/HOL/Library/Sum_Of_Squares.
  2338 
  2339 * New method "linarith" invokes existing linear arithmetic decision
  2340 procedure only.
  2341 
  2342 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2343 
  2344 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2345 Causes full type information to be output to the ATPs.  This slows
  2346 ATPs down considerably but eliminates a source of unsound "proofs"
  2347 that fail later.
  2348 
  2349 * New method "metisFT": A version of metis that uses full type
  2350 information in order to avoid failures of proof reconstruction.
  2351 
  2352 * New evaluator "approximate" approximates an real valued term using
  2353 the same method as the approximation method.
  2354 
  2355 * Method "approximate" now supports arithmetic expressions as
  2356 boundaries of intervals and implements interval splitting and Taylor
  2357 series expansion.
  2358 
  2359 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2360 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2361 
  2362 * New theory SupInf of the supremum and infimum operators for sets of
  2363 reals.
  2364 
  2365 * New theory Probability, which contains a development of measure
  2366 theory, eventually leading to Lebesgue integration and probability.
  2367 
  2368 * Extended Multivariate Analysis to include derivation and Brouwer's
  2369 fixpoint theorem.
  2370 
  2371 * Reorganization of number theory, INCOMPATIBILITY:
  2372   - new number theory development for nat and int, in theories Divides
  2373     and GCD as well as in new session Number_Theory
  2374   - some constants and facts now suffixed with _nat and _int
  2375     accordingly
  2376   - former session NumberTheory now named Old_Number_Theory, including
  2377     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2378   - moved theory Pocklington from src/HOL/Library to
  2379     src/HOL/Old_Number_Theory
  2380 
  2381 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2382 lcm of finite and infinite sets. It is shown that they form a complete
  2383 lattice.
  2384 
  2385 * Class semiring_div requires superclass no_zero_divisors and proof of
  2386 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2387 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2388 generalized to class semiring_div, subsuming former theorems
  2389 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2390 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2391 INCOMPATIBILITY.
  2392 
  2393 * Refinements to lattice classes and sets:
  2394   - less default intro/elim rules in locale variant, more default
  2395     intro/elim rules in class variant: more uniformity
  2396   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2397     le_inf_iff
  2398   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2399     sup_aci)
  2400   - renamed ACI to inf_sup_aci
  2401   - new class "boolean_algebra"
  2402   - class "complete_lattice" moved to separate theory
  2403     "Complete_Lattice"; corresponding constants (and abbreviations)
  2404     renamed and with authentic syntax:
  2405     Set.Inf ~>    Complete_Lattice.Inf
  2406     Set.Sup ~>    Complete_Lattice.Sup
  2407     Set.INFI ~>   Complete_Lattice.INFI
  2408     Set.SUPR ~>   Complete_Lattice.SUPR
  2409     Set.Inter ~>  Complete_Lattice.Inter
  2410     Set.Union ~>  Complete_Lattice.Union
  2411     Set.INTER ~>  Complete_Lattice.INTER
  2412     Set.UNION ~>  Complete_Lattice.UNION
  2413   - authentic syntax for
  2414     Set.Pow
  2415     Set.image
  2416   - mere abbreviations:
  2417     Set.empty               (for bot)
  2418     Set.UNIV                (for top)
  2419     Set.inter               (for inf, formerly Set.Int)
  2420     Set.union               (for sup, formerly Set.Un)
  2421     Complete_Lattice.Inter  (for Inf)
  2422     Complete_Lattice.Union  (for Sup)
  2423     Complete_Lattice.INTER  (for INFI)
  2424     Complete_Lattice.UNION  (for SUPR)
  2425   - object-logic definitions as far as appropriate
  2426 
  2427 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2428 Un_subset_iff are explicitly deleted as default simp rules; then also
  2429 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2430 deleted to achieve the desired effect.
  2431 
  2432 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2433 rules by default any longer; the same applies to min_max.inf_absorb1
  2434 etc.  INCOMPATIBILITY.
  2435 
  2436 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2437 pred_set_conv by default.  INCOMPATIBILITY.
  2438 
  2439 * Power operations on relations and functions are now one dedicated
  2440 constant "compow" with infix syntax "^^".  Power operation on
  2441 multiplicative monoids retains syntax "^" and is now defined generic
  2442 in class power.  INCOMPATIBILITY.
  2443 
  2444 * Relation composition "R O S" now has a more standard argument order:
  2445 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2446 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2447 break, since the O_assoc rule was not rewritten like this.  Fix using
  2448 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2449 
  2450 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2451 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2452 INCOMPATIBILITY.
  2453 
  2454 * Most rules produced by inductive and datatype package have mandatory
  2455 prefixes.  INCOMPATIBILITY.
  2456 
  2457 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2458 the attribute of the same name.  Each of the theorems in the list
  2459 DERIV_intros assumes composition with an additional function and
  2460 matches a variable to the derivative, which has to be solved by the
  2461 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2462 of most elementary terms.  Former Maclauren.DERIV_tac and
  2463 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2464 INCOMPATIBILITY.
  2465 
  2466 * Code generator attributes follow the usual underscore convention:
  2467     code_unfold     replaces    code unfold
  2468     code_post       replaces    code post
  2469     etc.
  2470   INCOMPATIBILITY.
  2471 
  2472 * Renamed methods:
  2473     sizechange -> size_change
  2474     induct_scheme -> induction_schema
  2475   INCOMPATIBILITY.
  2476 
  2477 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2478 INCOMPATIBILITY, use "undefined" directly.
  2479 
  2480 * Renamed theorems:
  2481     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2482     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2483     Suc_plus1 -> Suc_eq_plus1
  2484     *anti_sym -> *antisym*
  2485     vector_less_eq_def -> vector_le_def
  2486   INCOMPATIBILITY.
  2487 
  2488 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2489 INCOMPATIBILITY.
  2490 
  2491 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2492 INCOMPATIBILITY.
  2493 
  2494 
  2495 *** HOLCF ***
  2496 
  2497 * Theory Representable defines a class "rep" of domains that are
  2498 representable (via an ep-pair) in the universal domain type "udom".
  2499 Instances are provided for all type constructors defined in HOLCF.
  2500 
  2501 * The 'new_domain' command is a purely definitional version of the
  2502 domain package, for representable domains.  Syntax is identical to the
  2503 old domain package.  The 'new_domain' package also supports indirect
  2504 recursion using previously-defined type constructors.  See
  2505 src/HOLCF/ex/New_Domain.thy for examples.
  2506 
  2507 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2508 on the left-hand side of an equation, and then performs
  2509 simplification.  Rewriting is done using rules declared with the
  2510 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2511 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2512 
  2513 * The pattern-match compiler in 'fixrec' can now handle constructors
  2514 with HOL function types.  Pattern-match combinators for the Pair
  2515 constructor are pre-configured.
  2516 
  2517 * The 'fixrec' package now produces better fixed-point induction rules
  2518 for mutually-recursive definitions:  Induction rules have conclusions
  2519 of the form "P foo bar" instead of "P <foo, bar>".
  2520 
  2521 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2522 been renamed to "below".  The name "below" now replaces "less" in many
  2523 theorem names.  (Legacy theorem names using "less" are still supported
  2524 as well.)
  2525 
  2526 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2527 patterns can be used to generate strictness rules, or to make
  2528 functions more strict (much like the bang-patterns supported by the
  2529 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2530 examples.
  2531 
  2532 
  2533 *** ML ***
  2534 
  2535 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2536 errors and run-time exceptions, including detailed source positions.
  2537 
  2538 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2539 identified entries, with some additional information such as source
  2540 position, logical grouping etc.
  2541 
  2542 * Theory and context data is now introduced by the simplified and
  2543 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2544 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2545 copy operation) is still available for some time.
  2546 
  2547 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2548 provides a high-level programming interface to synchronized state
  2549 variables with atomic update.  This works via pure function
  2550 application within a critical section -- its runtime should be as
  2551 short as possible; beware of deadlocks if critical code is nested,
  2552 either directly or indirectly via other synchronized variables!
  2553 
  2554 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2555 wraps raw ML references, explicitly indicating their non-thread-safe
  2556 behaviour.  The Isar toplevel keeps this structure open, to
  2557 accommodate Proof General as well as quick and dirty interactive
  2558 experiments with references.
  2559 
  2560 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2561 parallel tactical reasoning.
  2562 
  2563 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2564 are similar to SUBPROOF, but are slightly more flexible: only the
  2565 specified parts of the subgoal are imported into the context, and the
  2566 body tactic may introduce new subgoals and schematic variables.
  2567 
  2568 * Old tactical METAHYPS, which does not observe the proof context, has
  2569 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2570 or Subgoal.FOCUS etc.
  2571 
  2572 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2573 functors have their own ML name space there is no point to mark them
  2574 separately.)  Minor INCOMPATIBILITY.
  2575 
  2576 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2577 
  2578 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2579 INCOMPATIBILITY.
  2580 
  2581 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2582 mode, which avoids critical setmp.
  2583 
  2584 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2585 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2586 Attrib/Method.setup introduced in Isabelle2009.
  2587 
  2588 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2589 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2590 last resort.  INCOMPATIBILITY.
  2591 
  2592 * Display.pretty_thm now requires a proper context (cf. former
  2593 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2594 or even Display.pretty_thm_without_context as last resort.
  2595 INCOMPATIBILITY.
  2596 
  2597 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2598 Syntax.pretty_typ/term directly, preferably with proper context
  2599 instead of global theory.
  2600 
  2601 
  2602 *** System ***
  2603 
  2604 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2605 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2606 usedir option -q.
  2607 
  2608 * Support for additional "Isabelle components" via etc/components, see
  2609 also the system manual.
  2610 
  2611 * The isabelle makeall tool now operates on all components with
  2612 IsaMakefile, not just hardwired "logics".
  2613 
  2614 * Removed "compress" option from isabelle-process and isabelle usedir;
  2615 this is always enabled.
  2616 
  2617 * Discontinued support for Poly/ML 4.x versions.
  2618 
  2619 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2620 on a given logic image.  This requires the lighttpd webserver and is
  2621 currently supported on Linux only.
  2622 
  2623 
  2624 
  2625 New in Isabelle2009 (April 2009)
  2626 --------------------------------
  2627 
  2628 *** General ***
  2629 
  2630 * Simplified main Isabelle executables, with less surprises on
  2631 case-insensitive file-systems (such as Mac OS).
  2632 
  2633   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2634     "isatool."
  2635 
  2636   - The former "isabelle" alias for "isabelle-process" has been
  2637     removed (should rarely occur to regular users).
  2638 
  2639   - The former "isabelle-interface" and its alias "Isabelle" have been
  2640     removed (interfaces are now regular Isabelle tools).
  2641 
  2642 Within scripts and make files, the Isabelle environment variables
  2643 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2644 respectively.  (The latter are still available as legacy feature.)
  2645 
  2646 The old isabelle-interface wrapper could react in confusing ways if
  2647 the interface was uninstalled or changed otherwise.  Individual
  2648 interface tool configuration is now more explicit, see also the
  2649 Isabelle system manual.  In particular, Proof General is now available
  2650 via "isabelle emacs".
  2651 
  2652 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2653 purge installed copies of Isabelle executables and re-run "isabelle
  2654 install -p ...", or use symlinks.
  2655 
  2656 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2657 old ~/isabelle, which was slightly non-standard and apt to cause
  2658 surprises on case-insensitive file-systems (such as Mac OS).
  2659 
  2660 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2661 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2662 care is required when using older releases of Isabelle.  Note that
  2663 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2664 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2665 
  2666 * Proofs of fully specified statements are run in parallel on
  2667 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2668 a regular 4-core machine, if the initial heap space is made reasonably
  2669 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2670 
  2671 * The main reference manuals ("isar-ref", "implementation", and
  2672 "system") have been updated and extended.  Formally checked references
  2673 as hyperlinks are now available uniformly.
  2674 
  2675 
  2676 *** Pure ***
  2677 
  2678 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2679 respects.  The most important changes are listed below.  See the
  2680 Tutorial on Locales ("locales" manual) for details.
  2681 
  2682 - In locale expressions, instantiation replaces renaming.  Parameters
  2683 must be declared in a for clause.  To aid compatibility with previous
  2684 parameter inheritance, in locale declarations, parameters that are not
  2685 'touched' (instantiation position "_" or omitted) are implicitly added
  2686 with their syntax at the beginning of the for clause.
  2687 
  2688 - Syntax from abbreviations and definitions in locales is available in
  2689 locale expressions and context elements.  The latter is particularly
  2690 useful in locale declarations.
  2691 
  2692 - More flexible mechanisms to qualify names generated by locale
  2693 expressions.  Qualifiers (prefixes) may be specified in locale
  2694 expressions, and can be marked as mandatory (syntax: "name!:") or
  2695 optional (syntax "name?:").  The default depends for plain "name:"
  2696 depends on the situation where a locale expression is used: in
  2697 commands 'locale' and 'sublocale' prefixes are optional, in
  2698 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2699 implicit qualifiers derived from the parameter names of a locale are
  2700 no longer generated.
  2701 
  2702 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2703 instantiation clause in "interpretation" and "interpret" (square
  2704 brackets) is no longer available.  Use locale expressions.
  2705 
  2706 - When converting proof scripts, mandatory qualifiers in
  2707 'interpretation' and 'interpret' should be retained by default, even
  2708 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2709 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2710 in locale expressions range over a single locale instance only.
  2711 
  2712 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2713 In existing theorem specifications replace the includes element by the
  2714 respective context elements of the included locale, omitting those
  2715 that are already present in the theorem specification.  Multiple
  2716 assume elements of a locale should be replaced by a single one
  2717 involving the locale predicate.  In the proof body, declarations (most
  2718 notably theorems) may be regained by interpreting the respective
  2719 locales in the proof context as required (command "interpret").
  2720 
  2721 If using "includes" in replacement of a target solely because the
  2722 parameter types in the theorem are not as general as in the target,
  2723 consider declaring a new locale with additional type constraints on
  2724 the parameters (context element "constrains").
  2725 
  2726 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2727 
  2728 - Locale interpretation commands no longer attempt to simplify goal.
  2729 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2730 methods intro_locales and unfold_locales to clarify.
  2731 
  2732 - Locale interpretation commands no longer accept interpretation
  2733 attributes.  INCOMPATIBILITY.
  2734 
  2735 * Class declaration: so-called "base sort" must not be given in import
  2736 list any longer, but is inferred from the specification.  Particularly
  2737 in HOL, write
  2738 
  2739     class foo = ...
  2740 
  2741 instead of
  2742 
  2743     class foo = type + ...
  2744 
  2745 * Class target: global versions of theorems stemming do not carry a
  2746 parameter prefix any longer.  INCOMPATIBILITY.
  2747 
  2748 * Class 'instance' command no longer accepts attached definitions.
  2749 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2750 
  2751 * Recovered hiding of consts, which was accidentally broken in
  2752 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2753 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2754 
  2755 * Slightly more coherent Pure syntax, with updated documentation in
  2756 isar-ref manual.  Removed locales meta_term_syntax and
  2757 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2758 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2759 directly in regular applications.
  2760 
  2761 * There is a new syntactic category "float_const" for signed decimal
  2762 fractions (e.g. 123.45 or -123.45).
  2763 
  2764 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2765 interface with 'setup' command instead.
  2766 
  2767 * Command 'local_setup' is similar to 'setup', but operates on a local
  2768 theory context.
  2769 
  2770 * The 'axiomatization' command now only works within a global theory
  2771 context.  INCOMPATIBILITY.
  2772 
  2773 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2774 hypotheses.  Sorts required in the course of reasoning need to be
  2775 covered by the constraints in the initial statement, completed by the
  2776 type instance information of the background theory.  Non-trivial sort
  2777 hypotheses, which rarely occur in practice, may be specified via
  2778 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2779 
  2780   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2781 
  2782 The result contains an implicit sort hypotheses as before --
  2783 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2784 normalization.
  2785 
  2786 * Generalized Isar history, with support for linear undo, direct state
  2787 addressing etc.
  2788 
  2789 * Changed defaults for unify configuration options:
  2790 
  2791   unify_trace_bound = 50 (formerly 25)
  2792   unify_search_bound = 60 (formerly 30)
  2793 
  2794 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2795 
  2796   a) On theory merge, the last set of code equations for a particular
  2797      constant is taken (in accordance with the policy applied by other
  2798      parts of the code generator framework).
  2799 
  2800   b) Code equations stemming from explicit declarations (e.g. code
  2801      attribute) gain priority over default code equations stemming
  2802      from definition, primrec, fun etc.
  2803 
  2804 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2805 
  2806 * Unified theorem tables for both code generators.  Thus [code
  2807 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2808 
  2809 * Command 'find_consts' searches for constants based on type and name
  2810 patterns, e.g.
  2811 
  2812     find_consts "_ => bool"
  2813 
  2814 By default, matching is against subtypes, but it may be restricted to
  2815 the whole type.  Searching by name is possible.  Multiple queries are
  2816 conjunctive and queries may be negated by prefixing them with a
  2817 hyphen:
  2818 
  2819     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2820 
  2821 * New 'find_theorems' criterion "solves" matches theorems that
  2822 directly solve the current goal (modulo higher-order unification).
  2823 
  2824 * Auto solve feature for main theorem statements: whenever a new goal
  2825 is stated, "find_theorems solves" is called; any theorems that could
  2826 solve the lemma directly are listed as part of the goal state.
  2827 Cf. associated options in Proof General Isabelle settings menu,
  2828 enabled by default, with reasonable timeout for pathological cases of
  2829 higher-order unification.
  2830 
  2831 
  2832 *** Document preparation ***
  2833 
  2834 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2835 demanding keyword 'by' and supporting the full method expression
  2836 syntax just like the Isar command 'by'.
  2837 
  2838 
  2839 *** HOL ***
  2840 
  2841 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2842 points Main and Complex_Main remain as before.
  2843 
  2844 * Logic image HOL-Plain provides a minimal HOL with the most important
  2845 tools available (inductive, datatype, primrec, ...).  This facilitates
  2846 experimentation and tool development.  Note that user applications
  2847 (and library theories) should never refer to anything below theory
  2848 Main, as before.
  2849 
  2850 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2851 experimentation due to shorter build times.
  2852 
  2853 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2854 were previously part of former HOL-Complex.  Entry point Hyperreal
  2855 remains valid, but theories formerly using Complex_Main should now use
  2856 new entry point Hypercomplex.
  2857 
  2858 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2859 Posix processes.  Avoids potentially expensive forking of the ML
  2860 process.  New thread-based implementation also works on non-Unix
  2861 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2862 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2863 commands are covered in the isar-ref manual.
  2864 
  2865 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2866 sledgehammer without local ATP installation (Vampire etc.). Other
  2867 provers may be included via suitable ML wrappers, see also
  2868 src/HOL/ATP_Linkup.thy.
  2869 
  2870 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2871 menu.
  2872 
  2873 * The metis method no longer fails because the theorem is too trivial
  2874 (contains the empty clause).
  2875 
  2876 * The metis method now fails in the usual manner, rather than raising
  2877 an exception, if it determines that it cannot prove the theorem.
  2878 
  2879 * Method "coherent" implements a prover for coherent logic (see also
  2880 src/Tools/coherent.ML).
  2881 
  2882 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2883 "undefined" is the right choice to replace "arbitrary", though
  2884 logically there is no difference.  INCOMPATIBILITY.
  2885 
  2886 * Command "value" now integrates different evaluation mechanisms.  The
  2887 result of the first successful evaluation mechanism is printed.  In
  2888 square brackets a particular named evaluation mechanisms may be
  2889 specified (currently, [SML], [code] or [nbe]).  See further
  2890 src/HOL/ex/Eval_Examples.thy.
  2891 
  2892 * Normalization by evaluation now allows non-leftlinear equations.
  2893 Declare with attribute [code nbe].
  2894 
  2895 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2896 as the structured Isar versions "cases" and "induct", cf. the
  2897 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2898 are now presented as a list of individual projections
  2899 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2900 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2901 rare situations a different rule is selected --- notably nested tuple
  2902 elimination instead of former prod.exhaust: use explicit (case_tac t
  2903 rule: prod.exhaust) here.
  2904 
  2905 * Attributes "cases", "induct", "coinduct" support "del" option.
  2906 
  2907 * Removed fact "case_split_thm", which duplicates "case_split".
  2908 
  2909 * The option datatype has been moved to a new theory Option.  Renamed
  2910 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2911 
  2912 * New predicate "strict_mono" classifies strict functions on partial
  2913 orders.  With strict functions on linear orders, reasoning about
  2914 (in)equalities is facilitated by theorems "strict_mono_eq",
  2915 "strict_mono_less_eq" and "strict_mono_less".
  2916 
  2917 * Some set operations are now proper qualified constants with
  2918 authentic syntax.  INCOMPATIBILITY:
  2919 
  2920     op Int ~>   Set.Int
  2921     op Un ~>    Set.Un
  2922     INTER ~>    Set.INTER
  2923     UNION ~>    Set.UNION
  2924     Inter ~>    Set.Inter
  2925     Union ~>    Set.Union
  2926     {} ~>       Set.empty
  2927     UNIV ~>     Set.UNIV
  2928 
  2929 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2930 theory Set.
  2931 
  2932 * Auxiliary class "itself" has disappeared -- classes without any
  2933 parameter are treated as expected by the 'class' command.
  2934 
  2935 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2936 
  2937 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2938 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2939 
  2940 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2941 method "approximation".  It proves formulas on real values by using
  2942 interval arithmetic.  In the formulas are also the transcendental
  2943 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2944 allowed. For examples see
  2945 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2946 
  2947 * Theory "Reflection" now resides in HOL/Library.
  2948 
  2949 * Entry point to Word library now simply named "Word".
  2950 INCOMPATIBILITY.
  2951 
  2952 * Made source layout more coherent with logical distribution
  2953 structure:
  2954 
  2955     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2956     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2957     src/HOL/Library/GCD.thy ~> src/HOL/
  2958     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2959     src/HOL/Library/Parity.thy ~> src/HOL/
  2960     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2961     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2962     src/HOL/Real/Lubs.thy ~> src/HOL/
  2963     src/HOL/Real/PReal.thy ~> src/HOL/
  2964     src/HOL/Real/Rational.thy ~> src/HOL/
  2965     src/HOL/Real/RComplete.thy ~> src/HOL/
  2966     src/HOL/Real/RealDef.thy ~> src/HOL/
  2967     src/HOL/Real/RealPow.thy ~> src/HOL/
  2968     src/HOL/Real/Real.thy ~> src/HOL/
  2969     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2970     src/HOL/Complex/Complex.thy ~> src/HOL/
  2971     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2972     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2973     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2974     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2975     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2976     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2977     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2978     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2979     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2980     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2981     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2982     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2983     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2984     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2985     src/HOL/Real/Float ~> src/HOL/Library/
  2986     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2987     src/HOL/Real/RealVector.thy ~> src/HOL/
  2988 
  2989     src/HOL/arith_data.ML ~> src/HOL/Tools
  2990     src/HOL/hologic.ML ~> src/HOL/Tools
  2991     src/HOL/simpdata.ML ~> src/HOL/Tools
  2992     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2993     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2994     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2995     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2996     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2997     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2998     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2999 
  3000     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  3001     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  3002     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  3003     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  3004     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  3005     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  3006 
  3007 * If methods "eval" and "evaluation" encounter a structured proof
  3008 state with !!/==>, only the conclusion is evaluated to True (if
  3009 possible), avoiding strange error messages.
  3010 
  3011 * Method "sizechange" automates termination proofs using (a
  3012 modification of) the size-change principle.  Requires SAT solver.  See
  3013 src/HOL/ex/Termination.thy for examples.
  3014 
  3015 * Simplifier: simproc for let expressions now unfolds if bound
  3016 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  3017 
  3018 * Method "arith": Linear arithmetic now ignores all inequalities when
  3019 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  3020 
  3021 * New attribute "arith" for facts that should always be used
  3022 automatically by arithmetic. It is intended to be used locally in
  3023 proofs, e.g.
  3024 
  3025   assumes [arith]: "x > 0"
  3026 
  3027 Global usage is discouraged because of possible performance impact.
  3028 
  3029 * New classes "top" and "bot" with corresponding operations "top" and
  3030 "bot" in theory Orderings; instantiation of class "complete_lattice"
  3031 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  3032 
  3033 * Changed definition lemma "less_fun_def" in order to provide an
  3034 instance for preorders on functions; use lemma "less_le" instead.
  3035 INCOMPATIBILITY.
  3036 
  3037 * Theory Orderings: class "wellorder" moved here, with explicit
  3038 induction rule "less_induct" as assumption.  For instantiation of
  3039 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  3040 INCOMPATIBILITY.
  3041 
  3042 * Theory Orderings: added class "preorder" as superclass of "order".
  3043 INCOMPATIBILITY: Instantiation proofs for order, linorder
  3044 etc. slightly changed.  Some theorems named order_class.* now named
  3045 preorder_class.*.
  3046 
  3047 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  3048 "diag" to "Id_on".
  3049 
  3050 * Theory Finite_Set: added a new fold combinator of type
  3051 
  3052   ('a => 'b => 'b) => 'b => 'a set => 'b
  3053 
  3054 Occasionally this is more convenient than the old fold combinator
  3055 which is now defined in terms of the new one and renamed to
  3056 fold_image.
  3057 
  3058 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  3059 and "ring_simps" have been replaced by "algebra_simps" (which can be
  3060 extended with further lemmas!).  At the moment both still exist but
  3061 the former will disappear at some point.
  3062 
  3063 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  3064 class recpower.  Type-specific simp rules for various recpower types
  3065 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  3066 
  3067 rat_power_0    -> power_0
  3068 rat_power_Suc  -> power_Suc
  3069 realpow_0      -> power_0
  3070 realpow_Suc    -> power_Suc
  3071 complexpow_0   -> power_0
  3072 complexpow_Suc -> power_Suc
  3073 power_poly_0   -> power_0
  3074 power_poly_Suc -> power_Suc
  3075 
  3076 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  3077 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  3078 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  3079 of lemmas from Divides has been generalized from nat to class
  3080 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  3081 renames resulting from duplicate elimination:
  3082 
  3083     dvd_def_mod ~>          dvd_eq_mod_eq_0
  3084     zero_dvd_iff ~>         dvd_0_left_iff
  3085     dvd_0 ~>                dvd_0_right
  3086     DIVISION_BY_ZERO_DIV ~> div_by_0
  3087     DIVISION_BY_ZERO_MOD ~> mod_by_0
  3088     mult_div ~>             div_mult_self2_is_id
  3089     mult_mod ~>             mod_mult_self2_is_0
  3090 
  3091 * Theory IntDiv: removed many lemmas that are instances of class-based
  3092 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  3093 rename old lemmas as follows:
  3094 
  3095 dvd_diff               -> nat_dvd_diff
  3096 dvd_zminus_iff         -> dvd_minus_iff
  3097 mod_add1_eq            -> mod_add_eq
  3098 mod_mult1_eq           -> mod_mult_right_eq
  3099 mod_mult1_eq'          -> mod_mult_left_eq
  3100 mod_mult_distrib_mod   -> mod_mult_eq
  3101 nat_mod_add_left_eq    -> mod_add_left_eq
  3102 nat_mod_add_right_eq   -> mod_add_right_eq
  3103 nat_mod_div_trivial    -> mod_div_trivial
  3104 nat_mod_mod_trivial    -> mod_mod_trivial
  3105 zdiv_zadd_self1        -> div_add_self1
  3106 zdiv_zadd_self2        -> div_add_self2
  3107 zdiv_zmult_self1       -> div_mult_self2_is_id
  3108 zdiv_zmult_self2       -> div_mult_self1_is_id
  3109 zdvd_triv_left         -> dvd_triv_left
  3110 zdvd_triv_right        -> dvd_triv_right
  3111 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3112 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3113 zmod_zadd_left_eq      -> mod_add_left_eq
  3114 zmod_zadd_right_eq     -> mod_add_right_eq
  3115 zmod_zadd_self1        -> mod_add_self1
  3116 zmod_zadd_self2        -> mod_add_self2
  3117 zmod_zadd1_eq          -> mod_add_eq
  3118 zmod_zdiff1_eq         -> mod_diff_eq
  3119 zmod_zdvd_zmod         -> mod_mod_cancel
  3120 zmod_zmod_cancel       -> mod_mod_cancel
  3121 zmod_zmult_self1       -> mod_mult_self2_is_0
  3122 zmod_zmult_self2       -> mod_mult_self1_is_0
  3123 zmod_1                 -> mod_by_1
  3124 zdiv_1                 -> div_by_1
  3125 zdvd_abs1              -> abs_dvd_iff
  3126 zdvd_abs2              -> dvd_abs_iff
  3127 zdvd_refl              -> dvd_refl
  3128 zdvd_trans             -> dvd_trans
  3129 zdvd_zadd              -> dvd_add
  3130 zdvd_zdiff             -> dvd_diff
  3131 zdvd_zminus_iff        -> dvd_minus_iff
  3132 zdvd_zminus2_iff       -> minus_dvd_iff
  3133 zdvd_zmultD            -> dvd_mult_right
  3134 zdvd_zmultD2           -> dvd_mult_left
  3135 zdvd_zmult_mono        -> mult_dvd_mono
  3136 zdvd_0_right           -> dvd_0_right
  3137 zdvd_0_left            -> dvd_0_left_iff
  3138 zdvd_1_left            -> one_dvd
  3139 zminus_dvd_iff         -> minus_dvd_iff
  3140 
  3141 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3142 
  3143 * The real numbers offer decimal input syntax: 12.34 is translated
  3144 into 1234/10^2. This translation is not reversed upon output.
  3145 
  3146 * Theory Library/Polynomial defines an abstract type 'a poly of
  3147 univariate polynomials with coefficients of type 'a.  In addition to
  3148 the standard ring operations, it also supports div and mod.  Code
  3149 generation is also supported, using list-style constructors.
  3150 
  3151 * Theory Library/Inner_Product defines a class of real_inner for real
  3152 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3153 => real.  Class real_inner is a subclass of real_normed_vector from
  3154 theory RealVector.
  3155 
  3156 * Theory Library/Product_Vector provides instances for the product
  3157 type 'a * 'b of several classes from RealVector and Inner_Product.
  3158 Definitions of addition, subtraction, scalar multiplication, norms,
  3159 and inner products are included.
  3160 
  3161 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3162 addition to the field operations, numerals and case syntax are also
  3163 supported.
  3164 
  3165 * Theory Library/Diagonalize provides constructive version of Cantor's
  3166 first diagonalization argument.
  3167 
  3168 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3169 zlcm (for int); carried together from various gcd/lcm developements in
  3170 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3171 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3172 may recover tupled syntax as follows:
  3173 
  3174     hide (open) const gcd
  3175     abbreviation gcd where
  3176       "gcd == (%(a, b). GCD.gcd a b)"
  3177     notation (output)
  3178       GCD.gcd ("gcd '(_, _')")
  3179 
  3180 The same works for lcm, zgcd, zlcm.
  3181 
  3182 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3183 instantiations for algebraic structures.  Removed some duplicate
  3184 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3185 
  3186 * ML antiquotation @{code} takes a constant as argument and generates
  3187 corresponding code in background and inserts name of the corresponding
  3188 resulting ML value/function/datatype constructor binding in place.
  3189 All occurrences of @{code} with a single ML block are generated
  3190 simultaneously.  Provides a generic and safe interface for
  3191 instrumentalizing code generation.  See
  3192 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3193 In future you ought to refrain from ad-hoc compiling generated SML
  3194 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3195 cannot refer to constants for which user-defined serializations are
  3196 set.  Refer to the corresponding ML counterpart directly in that
  3197 cases.
  3198 
  3199 * Command 'rep_datatype': instead of theorem names the command now
  3200 takes a list of terms denoting the constructors of the type to be
  3201 represented as datatype.  The characteristic theorems have to be
  3202 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3203 have disappeared in favour of existing ones:
  3204 
  3205     unit_induct                 ~> unit.induct
  3206     prod_induct                 ~> prod.induct
  3207     sum_induct                  ~> sum.induct
  3208     Suc_Suc_eq                  ~> nat.inject
  3209     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3210 
  3211 
  3212 *** HOL-Algebra ***
  3213 
  3214 * New locales for orders and lattices where the equivalence relation
  3215 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3216 locales use a record structure with field eq for the equivalence.
  3217 
  3218 * New theory of factorial domains.
  3219 
  3220 * Units_l_inv and Units_r_inv are now simp rules by default.
  3221 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3222 and/or r_inv will now also require deletion of these lemmas.
  3223 
  3224 * Renamed the following theorems, INCOMPATIBILITY:
  3225 
  3226 UpperD ~> Upper_memD
  3227 LowerD ~> Lower_memD
  3228 least_carrier ~> least_closed
  3229 greatest_carrier ~> greatest_closed
  3230 greatest_Lower_above ~> greatest_Lower_below
  3231 one_zero ~> carrier_one_zero
  3232 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3233 
  3234 
  3235 *** HOL-Nominal ***
  3236 
  3237 * Nominal datatypes can now contain type-variables.
  3238 
  3239 * Commands 'nominal_inductive' and 'equivariance' work with local
  3240 theory targets.
  3241 
  3242 * Nominal primrec can now works with local theory targets and its
  3243 specification syntax now conforms to the general format as seen in
  3244 'inductive' etc.
  3245 
  3246 * Method "perm_simp" honours the standard simplifier attributes
  3247 (no_asm), (no_asm_use) etc.
  3248 
  3249 * The new predicate #* is defined like freshness, except that on the
  3250 left hand side can be a set or list of atoms.
  3251 
  3252 * Experimental command 'nominal_inductive2' derives strong induction
  3253 principles for inductive definitions.  In contrast to
  3254 'nominal_inductive', which can only deal with a fixed number of
  3255 binders, it can deal with arbitrary expressions standing for sets of
  3256 atoms to be avoided.  The only inductive definition we have at the
  3257 moment that needs this generalisation is the typing rule for Lets in
  3258 the algorithm W:
  3259 
  3260  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3261  -----------------------------------------------------------------
  3262          Gamma |- Let x be t1 in t2 : T2
  3263 
  3264 In this rule one wants to avoid all the binders that are introduced by
  3265 "close Gamma T1".  We are looking for other examples where this
  3266 feature might be useful.  Please let us know.
  3267 
  3268 
  3269 *** HOLCF ***
  3270 
  3271 * Reimplemented the simplification procedure for proving continuity
  3272 subgoals.  The new simproc is extensible; users can declare additional
  3273 continuity introduction rules with the attribute [cont2cont].
  3274 
  3275 * The continuity simproc now uses a different introduction rule for
  3276 solving continuity subgoals on terms with lambda abstractions.  In
  3277 some rare cases the new simproc may fail to solve subgoals that the
  3278 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3279 Potential INCOMPATIBILITY.
  3280 
  3281 * Command 'fixrec': specification syntax now conforms to the general
  3282 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3283 examples.  INCOMPATIBILITY.
  3284 
  3285 
  3286 *** ZF ***
  3287 
  3288 * Proof of Zorn's Lemma for partial orders.
  3289 
  3290 
  3291 *** ML ***
  3292 
  3293 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3294 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3295 depends on multithreading, so timouts will not work before Poly/ML
  3296 5.2.1!
  3297 
  3298 * High-level support for concurrent ML programming, see
  3299 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3300 particularly convenient to organize independent functional
  3301 computations.  The concept of "synchronized variables" provides a
  3302 higher-order interface for components with shared state, avoiding the
  3303 delicate details of mutexes and condition variables.  (Requires
  3304 Poly/ML 5.2.1 or later.)
  3305 
  3306 * ML bindings produced via Isar commands are stored within the Isar
  3307 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3308 become thread-safe and work with undo as expected (concerning
  3309 top-level bindings, not side-effects on global references).
  3310 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3311 compiler at runtime; really global bindings need to be given outside a
  3312 theory.  (Requires Poly/ML 5.2 or later.)
  3313 
  3314 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3315 context.  Top-level ML bindings are stored within the proof context in
  3316 a purely sequential fashion, disregarding the nested proof structure.
  3317 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3318 proof.  (Requires Poly/ML 5.2 or later.)
  3319 
  3320 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3321 and Method.setup, as well as Isar commands 'attribute_setup' and
  3322 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3323 existing code accordingly, or use plain 'setup' together with old
  3324 Method.add_method.
  3325 
  3326 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3327 to 'a -> thm, while results are always tagged with an authentic oracle
  3328 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3329 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3330 accordingly.  Note that extra performance may be gained by producing
  3331 the cterm carefully, avoiding slow Thm.cterm_of.
  3332 
  3333 * Simplified interface for defining document antiquotations via
  3334 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3335 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3336 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3337 examples.
  3338 
  3339 * More systematic treatment of long names, abstract name bindings, and
  3340 name space operations.  Basic operations on qualified names have been
  3341 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3342 Long_Name.append.  Old type bstring has been mostly replaced by
  3343 abstract type binding (see structure Binding), which supports precise
  3344 qualification by packages and local theory targets, as well as proper
  3345 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3346 bstring values into Binding.name, or better pass through abstract
  3347 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3348 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3349 
  3350 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3351 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3352 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3353 
  3354 * Disposed old type and term read functions (Sign.read_def_typ,
  3355 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3356 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3357 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3358 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3359 resort for legacy applications.
  3360 
  3361 * Disposed old declarations, tactics, tactic combinators that refer to
  3362 the simpset or claset of an implicit theory (such as Addsimps,
  3363 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3364 embedded ML text, or local_simpset_of with a proper context passed as
  3365 explicit runtime argument.
  3366 
  3367 * Rules and tactics that read instantiations (read_instantiate,
  3368 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3369 context, which is required for parsing and type-checking.  Moreover,
  3370 the variables are specified as plain indexnames, not string encodings
  3371 thereof.  INCOMPATIBILITY.
  3372 
  3373 * Generic Toplevel.add_hook interface allows to analyze the result of
  3374 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3375 for theorem dependency output of transactions resulting in a new
  3376 theory state.
  3377 
  3378 * ML antiquotations: block-structured compilation context indicated by
  3379 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3380 
  3381   @{binding name}                         - basic name binding
  3382   @{let ?pat = term}                      - term abbreviation (HO matching)
  3383   @{note name = fact}                     - fact abbreviation
  3384   @{thm fact}                             - singleton fact (with attributes)
  3385   @{thms fact}                            - general fact (with attributes)
  3386   @{lemma prop by method}                 - singleton goal
  3387   @{lemma prop by meth1 meth2}            - singleton goal
  3388   @{lemma prop1 ... propN by method}      - general goal
  3389   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3390   @{lemma (open) ...}                     - open derivation
  3391 
  3392 
  3393 *** System ***
  3394 
  3395 * The Isabelle "emacs" tool provides a specific interface to invoke
  3396 Proof General / Emacs, with more explicit failure if that is not
  3397 installed (the old isabelle-interface script silently falls back on
  3398 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3399 installation location of the Proof General distribution.
  3400 
  3401 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3402 the Isabelle process into a JVM/Scala application.  See
  3403 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3404 process wrapper has been discontinued.)
  3405 
  3406 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3407 
  3408 * Various status messages (with exact source position information) are
  3409 emitted, if proper markup print mode is enabled.  This allows
  3410 user-interface components to provide detailed feedback on internal
  3411 prover operations.
  3412 
  3413 
  3414 
  3415 New in Isabelle2008 (June 2008)
  3416 -------------------------------
  3417 
  3418 *** General ***
  3419 
  3420 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3421 and updated, with formally checked references as hyperlinks.
  3422 
  3423 * Theory loader: use_thy (and similar operations) no longer set the
  3424 implicit ML context, which was occasionally hard to predict and in
  3425 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3426 provides a proper context already.
  3427 
  3428 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3429 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3430 'use' within a theory file will do the job.
  3431 
  3432 * Name space merge now observes canonical order, i.e. the second space
  3433 is inserted into the first one, while existing entries in the first
  3434 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3435 swap theory imports.
  3436 
  3437 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3438 INCOMPATIBILITY in identifier syntax etc.
  3439 
  3440 * Outer syntax: string tokens no longer admit escaped white space,
  3441 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3442 white space without escapes.
  3443 
  3444 * Outer syntax: string tokens may contain arbitrary character codes
  3445 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3446 "foo_bar".
  3447 
  3448 
  3449 *** Pure ***
  3450 
  3451 * Context-dependent token translations.  Default setup reverts locally
  3452 fixed variables, and adds hilite markup for undeclared frees.
  3453 
  3454 * Unused theorems can be found using the new command 'unused_thms'.
  3455 There are three ways of invoking it:
  3456 
  3457 (1) unused_thms
  3458      Only finds unused theorems in the current theory.
  3459 
  3460 (2) unused_thms thy_1 ... thy_n -
  3461      Finds unused theorems in the current theory and all of its ancestors,
  3462      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3463 
  3464 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3465      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3466      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3467      their ancestors.
  3468 
  3469 In order to increase the readability of the list produced by
  3470 unused_thms, theorems that have been created by a particular instance
  3471 of a theory command such as 'inductive' or 'function' are considered
  3472 to belong to the same "group", meaning that if at least one theorem in
  3473 this group is used, the other theorems in the same group are no longer
  3474 reported as unused.  Moreover, if all theorems in the group are
  3475 unused, only one theorem in the group is displayed.
  3476 
  3477 Note that proof objects have to be switched on in order for
  3478 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3479 usually the case when using Proof General with the default settings).
  3480 
  3481 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3482 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3483 duplicate fact bindings, or even accidental fact duplications.  Note
  3484 that tools may maintain dynamically scoped facts systematically, using
  3485 PureThy.add_thms_dynamic.
  3486 
  3487 * Command 'hide' now allows to hide from "fact" name space as well.
  3488 
  3489 * Eliminated destructive theorem database, simpset, claset, and
  3490 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3491 update of theories within ML code.
  3492 
  3493 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3494 INCOMPATIBILITY, object-logics depending on former Pure require
  3495 additional setup PureThy.old_appl_syntax_setup; object-logics
  3496 depending on former CPure need to refer to Pure.
  3497 
  3498 * Commands 'use' and 'ML' are now purely functional, operating on
  3499 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3500 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3501 INCOMPATIBILITY.
  3502 
  3503 * Command 'setup': discontinued implicit version with ML reference.
  3504 
  3505 * Instantiation target allows for simultaneous specification of class
  3506 instance operations together with an instantiation proof.
  3507 Type-checking phase allows to refer to class operations uniformly.
  3508 See src/HOL/Complex/Complex.thy for an Isar example and
  3509 src/HOL/Library/Eval.thy for an ML example.
  3510 
  3511 * Indexing of literal facts: be more serious about including only
  3512 facts from the visible specification/proof context, but not the
  3513 background context (locale etc.).  Affects `prop` notation and method
  3514 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3515 situations.
  3516 
  3517 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3518 "(open)" option, which used to expose internal bound variables to the
  3519 proof text.
  3520 
  3521 * Isar statements: removed obsolete case "rule_context".
  3522 INCOMPATIBILITY, better use explicit fixes/assumes.
  3523 
  3524 * Locale proofs: default proof step now includes 'unfold_locales';
  3525 hence 'proof' without argument may be used to unfold locale
  3526 predicates.
  3527 
  3528 
  3529 *** Document preparation ***
  3530 
  3531 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3532 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3533 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3534 spot); renamed link color from "darkblue" to "linkcolor" (default
  3535 value unchanged, can be redefined via \definecolor); no longer sets
  3536 "a4paper" option (unnecessary or even intrusive).
  3537 
  3538 * Antiquotation @{lemma A method} proves proposition A by the given
  3539 method (either a method name or a method name plus (optional) method
  3540 arguments in parentheses) and prints A just like @{prop A}.
  3541 
  3542 
  3543 *** HOL ***
  3544 
  3545 * New primrec package.  Specification syntax conforms in style to
  3546 definition/function/....  No separate induction rule is provided.  The
  3547 "primrec" command distinguishes old-style and new-style specifications
  3548 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3549 When adjusting theories, beware: constants stemming from new-style
  3550 primrec specifications have authentic syntax.
  3551 
  3552 * Metis prover is now an order of magnitude faster, and also works
  3553 with multithreading.
  3554 
  3555 * Metis: the maximum number of clauses that can be produced from a
  3556 theorem is now given by the attribute max_clauses.  Theorems that
  3557 exceed this number are ignored, with a warning printed.
  3558 
  3559 * Sledgehammer no longer produces structured proofs by default. To
  3560 enable, declare [[sledgehammer_full = true]].  Attributes
  3561 reconstruction_modulus, reconstruction_sorts renamed
  3562 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3563 
  3564 * Method "induct_scheme" derives user-specified induction rules
  3565 from well-founded induction and completeness of patterns. This factors
  3566 out some operations that are done internally by the function package
  3567 and makes them available separately.  See
  3568 src/HOL/ex/Induction_Scheme.thy for examples.
  3569 
  3570 * More flexible generation of measure functions for termination
  3571 proofs: Measure functions can be declared by proving a rule of the
  3572 form "is_measure f" and giving it the [measure_function] attribute.
  3573 The "is_measure" predicate is logically meaningless (always true), and
  3574 just guides the heuristic.  To find suitable measure functions, the
  3575 termination prover sets up the goal "is_measure ?f" of the appropriate
  3576 type and generates all solutions by prolog-style backwards proof using
  3577 the declared rules.
  3578 
  3579 This setup also deals with rules like 
  3580 
  3581   "is_measure f ==> is_measure (list_size f)"
  3582 
  3583 which accommodates nested datatypes that recurse through lists.
  3584 Similar rules are predeclared for products and option types.
  3585 
  3586 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3587 
  3588   INCOMPATIBILITIES:
  3589 
  3590   - Definitions of overloaded constants on sets have to be replaced by
  3591     definitions on => and bool.
  3592 
  3593   - Some definitions of overloaded operators on sets can now be proved
  3594     using the definitions of the operators on => and bool.  Therefore,
  3595     the following theorems have been renamed:
  3596 
  3597       subset_def   -> subset_eq
  3598       psubset_def  -> psubset_eq
  3599       set_diff_def -> set_diff_eq
  3600       Compl_def    -> Compl_eq
  3601       Sup_set_def  -> Sup_set_eq
  3602       Inf_set_def  -> Inf_set_eq
  3603       sup_set_def  -> sup_set_eq
  3604       inf_set_def  -> inf_set_eq
  3605 
  3606   - Due to the incompleteness of the HO unification algorithm, some
  3607     rules such as subst may require manual instantiation, if some of
  3608     the unknowns in the rule is a set.
  3609 
  3610   - Higher order unification and forward proofs:
  3611     The proof pattern
  3612 
  3613       have "P (S::'a set)" <...>
  3614       then have "EX S. P S" ..
  3615 
  3616     no longer works (due to the incompleteness of the HO unification
  3617     algorithm) and must be replaced by the pattern
  3618 
  3619       have "EX S. P S"
  3620       proof
  3621         show "P S" <...>
  3622       qed
  3623 
  3624   - Calculational reasoning with subst (or similar rules):
  3625     The proof pattern
  3626 
  3627       have "P (S::'a set)" <...>
  3628       also have "S = T" <...>
  3629       finally have "P T" .
  3630 
  3631     no longer works (for similar reasons as the previous example) and
  3632     must be replaced by something like
  3633 
  3634       have "P (S::'a set)" <...>
  3635       moreover have "S = T" <...>
  3636       ultimately have "P T" by simp
  3637 
  3638   - Tactics or packages written in ML code:
  3639     Code performing pattern matching on types via
  3640 
  3641       Type ("set", [T]) => ...
  3642 
  3643     must be rewritten. Moreover, functions like strip_type or
  3644     binder_types no longer return the right value when applied to a
  3645     type of the form
  3646 
  3647       T1 => ... => Tn => U => bool
  3648 
  3649     rather than
  3650 
  3651       T1 => ... => Tn => U set
  3652 
  3653 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3654 Wellfounded_Relations to theory Wellfounded.
  3655 
  3656 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3657 
  3658 * Class finite no longer treats UNIV as class parameter.  Use class
  3659 enum from theory Library/Enum instead to achieve a similar effect.
  3660 INCOMPATIBILITY.
  3661 
  3662 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3663 and "Cons".  INCOMPATIBILITY.
  3664 
  3665 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3666 Potential INCOMPATIBILITY.
  3667 
  3668 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3669 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3670 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3671 
  3672 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3673 the same name in theory Orderings:
  3674 
  3675   less_trans
  3676   less_linear
  3677   le_imp_less_or_eq
  3678   le_less_trans
  3679   less_le_trans
  3680   less_not_sym
  3681   less_asym
  3682 
  3683 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3684 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3685 and different variable names.
  3686 
  3687 * Library/Option_ord.thy: Canonical order on option type.
  3688 
  3689 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3690 finite maps.
  3691 
  3692 * Library/Countable.thy: Type class for countable types.
  3693 
  3694 * Theory Int: The representation of numerals has changed.  The infix
  3695 operator BIT and the bit datatype with constructors B0 and B1 have
  3696 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3697 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3698 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3699 accordingly.
  3700 
  3701 * Theory Nat: definition of <= and < on natural numbers no longer
  3702 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3703 le_def and less_def have disappeared.  Consider lemmas not_less
  3704 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3705 
  3706 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3707 (whose purpose mainly is for various fold_set functionals) have been
  3708 abandoned in favor of the existing algebraic classes
  3709 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3710 lower_semilattice (resp. upper_semilattice) and linorder.
  3711 INCOMPATIBILITY.
  3712 
  3713 * Theory Transitive_Closure: induct and cases rules now declare proper
  3714 case_names ("base" and "step").  INCOMPATIBILITY.
  3715 
  3716 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3717 lattices.  The form set-specific version is available as
  3718 Inductive.lfp_ordinal_induct_set.
  3719 
  3720 * Renamed theorems "power.simps" to "power_int.simps".
  3721 INCOMPATIBILITY.
  3722 
  3723 * Class semiring_div provides basic abstract properties of semirings
  3724 with division and modulo operations.  Subsumes former class dvd_mod.
  3725 
  3726 * Merged theories IntDef, Numeral and IntArith into unified theory
  3727 Int.  INCOMPATIBILITY.
  3728 
  3729 * Theory Library/Code_Index: type "index" now represents natural
  3730 numbers rather than integers.  INCOMPATIBILITY.
  3731 
  3732 * New class "uminus" with operation "uminus" (split of from class
  3733 "minus" which now only has operation "minus", binary).
  3734 INCOMPATIBILITY.
  3735 
  3736 * Constants "card", "internal_split", "option_map" now with authentic
  3737 syntax.  INCOMPATIBILITY.
  3738 
  3739 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3740 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3741 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3742 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3743 Sup_set_def, le_def, less_def, option_map_def now with object
  3744 equality.  INCOMPATIBILITY.
  3745 
  3746 * Records. Removed K_record, and replaced it by pure lambda term
  3747 %x. c. The simplifier setup is now more robust against eta expansion.
  3748 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3749 
  3750 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3751 
  3752 * Library/ListVector: new theory of arithmetic vector operations.
  3753 
  3754 * Library/Order_Relation: new theory of various orderings as sets of
  3755 pairs.  Defines preorders, partial orders, linear orders and
  3756 well-orders on sets and on types.
  3757 
  3758 
  3759 *** ZF ***
  3760 
  3761 * Renamed some theories to allow to loading both ZF and HOL in the
  3762 same session:
  3763 
  3764   Datatype  -> Datatype_ZF
  3765   Inductive -> Inductive_ZF
  3766   Int       -> Int_ZF
  3767   IntDiv    -> IntDiv_ZF
  3768   Nat       -> Nat_ZF
  3769   List      -> List_ZF
  3770   Main      -> Main_ZF
  3771 
  3772 INCOMPATIBILITY: ZF theories that import individual theories below
  3773 Main might need to be adapted.  Regular theory Main is still
  3774 available, as trivial extension of Main_ZF.
  3775 
  3776 
  3777 *** ML ***
  3778 
  3779 * ML within Isar: antiquotation @{const name} or @{const
  3780 name(typargs)} produces statically-checked Const term.
  3781 
  3782 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3783 (of the same name).  Removed obsolete print command.
  3784 
  3785 * Removed obsolete "use_legacy_bindings" function.
  3786 
  3787 * The ``print mode'' is now a thread-local value derived from a global
  3788 template (the former print_mode reference), thus access becomes
  3789 non-critical.  The global print_mode reference is for session
  3790 management only; user-code should use print_mode_value,
  3791 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3792 
  3793 * Functions system/system_out provide a robust way to invoke external
  3794 shell commands, with propagation of interrupts (requires Poly/ML
  3795 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3796 
  3797 
  3798 *** System ***
  3799 
  3800 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3801 in accordance with Proof General 3.7, which prefers GNU emacs.
  3802 
  3803 * isatool tty runs Isabelle process with plain tty interaction;
  3804 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3805 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3806 
  3807 * isatool browser now works with Cygwin as well, using general
  3808 "javapath" function defined in Isabelle process environment.
  3809 
  3810 * YXML notation provides a simple and efficient alternative to
  3811 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3812 isatool yxml as described in the Isabelle system manual.
  3813 
  3814 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3815 provides general wrapper for managing an Isabelle process in a robust
  3816 fashion, with ``cooked'' output from stdin/stderr.
  3817 
  3818 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3819 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3820 
  3821 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3822 way of changing the user's settings is via
  3823 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3824 script.
  3825 
  3826 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3827 cores of the underlying machine, which is a good starting point for
  3828 optimal performance tuning.  The corresponding usedir option -M allows
  3829 "max" as an alias for "0".  WARNING: does not work on certain versions
  3830 of Mac OS (with Poly/ML 5.1).
  3831 
  3832 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3833 adverse effect of Isabelle flooding interactive front-ends (notably
  3834 ProofGeneral / XEmacs).
  3835 
  3836 
  3837 
  3838 New in Isabelle2007 (November 2007)
  3839 -----------------------------------
  3840 
  3841 *** General ***
  3842 
  3843 * More uniform information about legacy features, notably a
  3844 warning/error of "Legacy feature: ...", depending on the state of the
  3845 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3846 legacy features will disappear eventually.
  3847 
  3848 * Theory syntax: the header format ``theory A = B + C:'' has been
  3849 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3850 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3851 
  3852 * Theory syntax: the old non-Isar theory file format has been
  3853 discontinued altogether.  Note that ML proof scripts may still be used
  3854 with Isar theories; migration is usually quite simple with the ML
  3855 function use_legacy_bindings.  INCOMPATIBILITY.
  3856 
  3857 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3858 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3859 quotes.
  3860 
  3861 * Theory loader: be more serious about observing the static theory
  3862 header specifications (including optional directories), but not the
  3863 accidental file locations of previously successful loads.  The strict
  3864 update policy of former update_thy is now already performed by
  3865 use_thy, so the former has been removed; use_thys updates several
  3866 theories simultaneously, just as 'imports' within a theory header
  3867 specification, but without merging the results.  Potential
  3868 INCOMPATIBILITY: may need to refine theory headers and commands
  3869 ROOT.ML which depend on load order.
  3870 
  3871 * Theory loader: optional support for content-based file
  3872 identification, instead of the traditional scheme of full physical
  3873 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3874 (cf. the system manual).  The new scheme allows to work with
  3875 non-finished theories in persistent session images, such that source
  3876 files may be moved later on without requiring reloads.
  3877 
  3878 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3879 file (with the same base name as the theory) are considered a legacy
  3880 feature, which will disappear eventually. Even now, the theory loader
  3881 no longer maintains dependencies on such files.
  3882 
  3883 * Syntax: the scope for resolving ambiguities via type-inference is
  3884 now limited to individual terms, instead of whole simultaneous
  3885 specifications as before. This greatly reduces the complexity of the
  3886 syntax module and improves flexibility by separating parsing and
  3887 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3888 'fixes' etc.) are required in rare situations.
  3889 
  3890 * Syntax: constants introduced by new-style packages ('definition',
  3891 'abbreviation' etc.) are passed through the syntax module in
  3892 ``authentic mode''. This means that associated mixfix annotations
  3893 really stick to such constants, independently of potential name space
  3894 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3895 trees are represented slightly differently, may need to adapt syntax
  3896 translations accordingly. Use CONST marker in 'translations' and
  3897 @{const_syntax} antiquotation in 'parse_translation' etc.
  3898 
  3899 * Legacy goal package: reduced interface to the bare minimum required
  3900 to keep existing proof scripts running.  Most other user-level
  3901 functions are now part of the OldGoals structure, which is *not* open
  3902 by default (consider isatool expandshort before open OldGoals).
  3903 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3904 these tend to cause confusion about the actual goal (!) context being
  3905 used here, which is not necessarily the same as the_context().
  3906 
  3907 * Command 'find_theorems': supports "*" wild-card in "name:"
  3908 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3909 support a specific search form (see ProofGeneral/CHANGES).
  3910 
  3911 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3912 by default, which means that "prems" (and also "fixed variables") are
  3913 suppressed from proof state output.  Note that the ProofGeneral
  3914 settings mechanism allows to change and save options persistently, but
  3915 older versions of Isabelle will fail to start up if a negative prems
  3916 limit is imposed.
  3917 
  3918 * Local theory targets may be specified by non-nested blocks of
  3919 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3920 contain definitions, theorems etc., including any derived mechanism
  3921 that has been implemented on top of these primitives.  This concept
  3922 generalizes the existing ``theorem (in ...)'' towards more versatility
  3923 and scalability.
  3924 
  3925 * Proof General interface: proper undo of final 'end' command;
  3926 discontinued Isabelle/classic mode (ML proof scripts).
  3927 
  3928 
  3929 *** Document preparation ***
  3930 
  3931 * Added antiquotation @{theory name} which prints the given name,
  3932 after checking that it refers to a valid ancestor theory in the
  3933 current context.
  3934 
  3935 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3936 check the given source text as ML type/structure, printing verbatim.
  3937 
  3938 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3939 "c args == rhs" given in the current context.  (Any number of
  3940 arguments may be given on the LHS.)
  3941 
  3942 
  3943 *** Pure ***
  3944 
  3945 * The 'class' package offers a combination of axclass and locale to
  3946 achieve Haskell-like type classes in Isabelle.  Definitions and
  3947 theorems within a class context produce both relative results (with
  3948 implicit parameters according to the locale context), and polymorphic
  3949 constants with qualified polymorphism (according to the class
  3950 context).  Within the body context of a 'class' target, a separate
  3951 syntax layer ("user space type system") takes care of converting
  3952 between global polymorphic consts and internal locale representation.
  3953 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3954 "isatool doc classes" provides a tutorial.
  3955 
  3956 * Generic code generator framework allows to generate executable
  3957 code for ML and Haskell (including Isabelle classes).  A short usage
  3958 sketch:
  3959 
  3960     internal compilation:
  3961         export_code <list of constants (term syntax)> in SML
  3962     writing SML code to a file:
  3963         export_code <list of constants (term syntax)> in SML <filename>
  3964     writing OCaml code to a file:
  3965         export_code <list of constants (term syntax)> in OCaml <filename>
  3966     writing Haskell code to a bunch of files:
  3967         export_code <list of constants (term syntax)> in Haskell <filename>
  3968 
  3969     evaluating closed propositions to True/False using code generation:
  3970         method ``eval''
  3971 
  3972 Reasonable default setup of framework in HOL.
  3973 
  3974 Theorem attributs for selecting and transforming function equations theorems:
  3975 
  3976     [code fun]:        select a theorem as function equation for a specific constant
  3977     [code fun del]:    deselect a theorem as function equation for a specific constant
  3978     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3979     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3980 
  3981 User-defined serializations (target in {SML, OCaml, Haskell}):
  3982 
  3983     code_const <and-list of constants (term syntax)>
  3984       {(target) <and-list of const target syntax>}+
  3985 
  3986     code_type <and-list of type constructors>
  3987       {(target) <and-list of type target syntax>}+
  3988 
  3989     code_instance <and-list of instances>
  3990       {(target)}+
  3991         where instance ::= <type constructor> :: <class>
  3992 
  3993     code_class <and_list of classes>
  3994       {(target) <and-list of class target syntax>}+
  3995         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3996 
  3997 code_instance and code_class only are effective to target Haskell.
  3998 
  3999 For example usage see src/HOL/ex/Codegenerator.thy and
  4000 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  4001 generation from Isabelle/HOL theories is available via "isatool doc
  4002 codegen".
  4003 
  4004 * Code generator: consts in 'consts_code' Isar commands are now
  4005 referred to by usual term syntax (including optional type
  4006 annotations).
  4007 
  4008 * Command 'no_translations' removes translation rules from theory
  4009 syntax.
  4010 
  4011 * Overloaded definitions are now actually checked for acyclic
  4012 dependencies.  The overloading scheme is slightly more general than
  4013 that of Haskell98, although Isabelle does not demand an exact
  4014 correspondence to type class and instance declarations.
  4015 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  4016 exotic versions of overloading -- at the discretion of the user!
  4017 
  4018 Polymorphic constants are represented via type arguments, i.e. the
  4019 instantiation that matches an instance against the most general
  4020 declaration given in the signature.  For example, with the declaration
  4021 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  4022 as c(nat).  Overloading is essentially simultaneous structural
  4023 recursion over such type arguments.  Incomplete specification patterns
  4024 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  4025 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  4026 Command 'print_theory' outputs the normalized system of recursive
  4027 equations, see section "definitions".
  4028 
  4029 * Configuration options are maintained within the theory or proof
  4030 context (with name and type bool/int/string), providing a very simple
  4031 interface to a poor-man's version of general context data.  Tools may
  4032 declare options in ML (e.g. using Attrib.config_int) and then refer to
  4033 these values using Config.get etc.  Users may change options via an
  4034 associated attribute of the same name.  This form of context
  4035 declaration works particularly well with commands 'declare' or
  4036 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  4037 very easy to avoid global references, which would not observe Isar
  4038 toplevel undo/redo and fail to work with multithreading.
  4039 
  4040 Various global ML references of Pure and HOL have been turned into
  4041 configuration options:
  4042 
  4043   Unify.search_bound		unify_search_bound
  4044   Unify.trace_bound		unify_trace_bound
  4045   Unify.trace_simp		unify_trace_simp
  4046   Unify.trace_types		unify_trace_types
  4047   Simplifier.simp_depth_limit	simp_depth_limit
  4048   Blast.depth_limit		blast_depth_limit
  4049   DatatypeProp.dtK		datatype_distinctness_limit
  4050   fast_arith_neq_limit  	fast_arith_neq_limit
  4051   fast_arith_split_limit	fast_arith_split_limit
  4052 
  4053 * Named collections of theorems may be easily installed as context
  4054 data using the functor NamedThmsFun (see also
  4055 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  4056 attributes; there is also a toplevel print command.  This facility is
  4057 just a common case of general context data, which is the preferred way
  4058 for anything more complex than just a list of facts in canonical
  4059 order.
  4060 
  4061 * Isar: command 'declaration' augments a local theory by generic
  4062 declaration functions written in ML.  This enables arbitrary content
  4063 being added to the context, depending on a morphism that tells the
  4064 difference of the original declaration context wrt. the application
  4065 context encountered later on.
  4066 
  4067 * Isar: proper interfaces for simplification procedures.  Command
  4068 'simproc_setup' declares named simprocs (with match patterns, and body
  4069 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  4070 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  4071 
  4072 * Isar: an extra pair of brackets around attribute declarations
  4073 abbreviates a theorem reference involving an internal dummy fact,
  4074 which will be ignored later --- only the effect of the attribute on
  4075 the background context will persist.  This form of in-place
  4076 declarations is particularly useful with commands like 'declare' and
  4077 'using', for example ``have A using [[simproc a]] by simp''.
  4078 
  4079 * Isar: method "assumption" (and implicit closing of subproofs) now
  4080 takes simple non-atomic goal assumptions into account: after applying
  4081 an assumption as a rule the resulting subgoals are solved by atomic
  4082 assumption steps.  This is particularly useful to finish 'obtain'
  4083 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  4084 without referring to the original premise "!!x. P x ==> thesis" in the
  4085 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  4086 more permissive.
  4087 
  4088 * Isar: implicit use of prems from the Isar proof context is
  4089 considered a legacy feature.  Common applications like ``have A .''
  4090 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  4091 referencing facts explicitly here improves readability and
  4092 maintainability of proof texts.
  4093 
  4094 * Isar: improper proof element 'guess' is like 'obtain', but derives
  4095 the obtained context from the course of reasoning!  For example:
  4096 
  4097   assume "EX x y. A x & B y"   -- "any previous fact"
  4098   then guess x and y by clarify
  4099 
  4100 This technique is potentially adventurous, depending on the facts and
  4101 proof tools being involved here.
  4102 
  4103 * Isar: known facts from the proof context may be specified as literal
  4104 propositions, using ASCII back-quote syntax.  This works wherever
  4105 named facts used to be allowed so far, in proof commands, proof
  4106 methods, attributes etc.  Literal facts are retrieved from the context
  4107 according to unification of type and term parameters.  For example,
  4108 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  4109 theorems in the current context, then these are valid literal facts:
  4110 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  4111 
  4112 There is also a proof method "fact" which does the same composition
  4113 for explicit goal states, e.g. the following proof texts coincide with
  4114 certain special cases of literal facts:
  4115 
  4116   have "A" by fact                 ==  note `A`
  4117   have "A ==> B" by fact           ==  note `A ==> B`
  4118   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4119   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4120 
  4121 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4122 outer syntax.  Thus symbolic identifiers may be used without
  4123 additional white space in declarations like this: ``assume *: A''.
  4124 
  4125 * Isar: 'print_facts' prints all local facts of the current context,
  4126 both named and unnamed ones.
  4127 
  4128 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4129 
  4130   def x == "t" and y == "u"
  4131 
  4132 * Isar: added command 'unfolding', which is structurally similar to
  4133 'using', but affects both the goal state and facts by unfolding given
  4134 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4135 'unfolded' attribute may be replaced by first-class proof text.
  4136 
  4137 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4138 and command 'unfolding' now all support object-level equalities
  4139 (potentially conditional).  The underlying notion of rewrite rule is
  4140 analogous to the 'rule_format' attribute, but *not* that of the
  4141 Simplifier (which is usually more generous).
  4142 
  4143 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4144 premises of a theorem by n. Useful in conjunction with drule.
  4145 
  4146 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4147 method expression within a sandbox consisting of the first N
  4148 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4149 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4150 simplifies all new goals that emerge from applying rule foo to the
  4151 originally first one.
  4152 
  4153 * Isar: schematic goals are no longer restricted to higher-order
  4154 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4155 expected.
  4156 
  4157 * Isar: the conclusion of a long theorem statement is now either
  4158 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4159 (essentially a disjunction of cases with local parameters and
  4160 assumptions).  The latter allows to express general elimination rules
  4161 adequately; in this notation common elimination rules look like this:
  4162 
  4163   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4164     assumes "EX x. P x"
  4165     obtains x where "P x"
  4166 
  4167   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4168     assumes "A & B"
  4169     obtains A and B
  4170 
  4171   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4172     assumes "A | B"
  4173     obtains
  4174       A
  4175     | B
  4176 
  4177 The subsequent classical rules even refer to the formal "thesis"
  4178 explicitly:
  4179 
  4180   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4181     obtains "~ thesis"
  4182 
  4183   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4184     obtains "thesis ==> something"
  4185 
  4186 The actual proof of an 'obtains' statement is analogous to that of the
  4187 Isar proof element 'obtain', only that there may be several cases.
  4188 Optional case names may be specified in parentheses; these will be
  4189 available both in the present proof and as annotations in the
  4190 resulting rule, for later use with the 'cases' method (cf. attribute
  4191 case_names).
  4192 
  4193 * Isar: the assumptions of a long theorem statement are available as
  4194 "assms" fact in the proof context.  This is more appropriate than the
  4195 (historical) "prems", which refers to all assumptions of the current
  4196 context, including those from the target locale, proof body etc.
  4197 
  4198 * Isar: 'print_statement' prints theorems from the current theory or
  4199 proof context in long statement form, according to the syntax of a
  4200 top-level lemma.
  4201 
  4202 * Isar: 'obtain' takes an optional case name for the local context
  4203 introduction rule (default "that").
  4204 
  4205 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4206 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4207 to occur.
  4208 
  4209 * Pure: syntax "CONST name" produces a fully internalized constant
  4210 according to the current context.  This is particularly useful for
  4211 syntax translations that should refer to internal constant
  4212 representations independently of name spaces.
  4213 
  4214 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4215 instead of "FOO ". This allows multiple binder declarations to coexist
  4216 in the same context.  INCOMPATIBILITY.
  4217 
  4218 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4219 primitive that also works in a locale context (both for constants and
  4220 fixed variables). Type declaration and internal syntactic representation
  4221 of given constants retrieved from the context. Likewise, the
  4222 'no_notation' command allows to remove given syntax annotations from the
  4223 current context.
  4224 
  4225 * Isar/locales: new derived specification elements 'axiomatization',
  4226 'definition', 'abbreviation', which support type-inference, admit
  4227 object-level specifications (equality, equivalence).  See also the
  4228 isar-ref manual.  Examples:
  4229 
  4230   axiomatization
  4231     eq  (infix "===" 50) where
  4232     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4233 
  4234   definition "f x y = x + y + 1"
  4235   definition g where "g x = f x x"
  4236 
  4237   abbreviation
  4238     neq  (infix "=!=" 50) where
  4239     "x =!= y == ~ (x === y)"
  4240 
  4241 These specifications may be also used in a locale context.  Then the
  4242 constants being introduced depend on certain fixed parameters, and the
  4243 constant name is qualified by the locale base name.  An internal
  4244 abbreviation takes care for convenient input and output, making the
  4245 parameters implicit and using the original short name.  See also
  4246 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4247 entities from a monomorphic theory.
  4248 
  4249 Presently, abbreviations are only available 'in' a target locale, but
  4250 not inherited by general import expressions.  Also note that
  4251 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4252 'translations' in common applications.  The "no_abbrevs" print mode
  4253 prevents folding of abbreviations in term output.
  4254 
  4255 Concrete syntax is attached to specified constants in internal form,
  4256 independently of name spaces.  The parse tree representation is
  4257 slightly different -- use 'notation' instead of raw 'syntax', and
  4258 'translations' with explicit "CONST" markup to accommodate this.
  4259 
  4260 * Pure/Isar: unified syntax for new-style specification mechanisms
  4261 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4262 full type inference and dummy patterns ("_").  For example:
  4263 
  4264   definition "K x _ = x"
  4265 
  4266   inductive conj for A B
  4267   where "A ==> B ==> conj A B"
  4268 
  4269 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4270 the current context.  Print mode "no_abbrevs" prevents inversion of
  4271 abbreviations on output.
  4272 
  4273 * Isar/locales: improved parameter handling: use of locales "var" and
  4274 "struct" no longer necessary; - parameter renamings are no longer
  4275 required to be injective.  For example, this allows to define
  4276 endomorphisms as locale endom = homom mult mult h.
  4277 
  4278 * Isar/locales: changed the way locales with predicates are defined.
  4279 Instead of accumulating the specification, the imported expression is
  4280 now an interpretation.  INCOMPATIBILITY: different normal form of
  4281 locale expressions.  In particular, in interpretations of locales with
  4282 predicates, goals repesenting already interpreted fragments are not
  4283 removed automatically.  Use methods `intro_locales' and
  4284 `unfold_locales'; see below.
  4285 
  4286 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4287 provide backward reasoning on locales predicates.  The methods are
  4288 aware of interpretations and discharge corresponding goals.
  4289 `intro_locales' is less aggressive then `unfold_locales' and does not
  4290 unfold predicates to assumptions.
  4291 
  4292 * Isar/locales: the order in which locale fragments are accumulated
  4293 has changed.  This enables to override declarations from fragments due
  4294 to interpretations -- for example, unwanted simp rules.
  4295 
  4296 * Isar/locales: interpretation in theories and proof contexts has been
  4297 extended.  One may now specify (and prove) equations, which are
  4298 unfolded in interpreted theorems.  This is useful for replacing
  4299 defined concepts (constants depending on locale parameters) by
  4300 concepts already existing in the target context.  Example:
  4301 
  4302   interpretation partial_order ["op <= :: [int, int] => bool"]
  4303     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4304 
  4305 Typically, the constant `partial_order.less' is created by a
  4306 definition specification element in the context of locale
  4307 partial_order.
  4308 
  4309 * Method "induct": improved internal context management to support
  4310 local fixes and defines on-the-fly. Thus explicit meta-level
  4311 connectives !!  and ==> are rarely required anymore in inductive goals
  4312 (using object-logic connectives for this purpose has been long
  4313 obsolete anyway). Common proof patterns are explained in
  4314 src/HOL/Induct/Common_Patterns.thy, see also
  4315 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4316 examples.
  4317 
  4318 * Method "induct": improved handling of simultaneous goals. Instead of
  4319 introducing object-level conjunction, the statement is now split into
  4320 several conclusions, while the corresponding symbolic cases are nested
  4321 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4322 see src/HOL/Induct/Common_Patterns.thy, for example.
  4323 
  4324 * Method "induct": mutual induction rules are now specified as a list
  4325 of rule sharing the same induction cases. HOL packages usually provide
  4326 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4327 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4328 mutual induction rules differently, i.e. like this:
  4329 
  4330   (induct rule: foo_bar.inducts)
  4331   (induct set: foo bar)
  4332   (induct pred: foo bar)
  4333   (induct type: foo bar)
  4334 
  4335 The ML function ProjectRule.projections turns old-style rules into the
  4336 new format.
  4337 
  4338 * Method "coinduct": dual of induction, see
  4339 src/HOL/Library/Coinductive_List.thy for various examples.
  4340 
  4341 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4342 considered a legacy feature.
  4343 
  4344 * Attribute "symmetric" produces result with standardized schematic
  4345 variables (index 0).  Potential INCOMPATIBILITY.
  4346 
  4347 * Simplifier: by default the simplifier trace only shows top level
  4348 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4349 default. Thus there is less danger of being flooded by the trace. The
  4350 trace indicates where parts have been suppressed.
  4351   
  4352 * Provers/classical: removed obsolete classical version of elim_format
  4353 attribute; classical elim/dest rules are now treated uniformly when
  4354 manipulating the claset.
  4355 
  4356 * Provers/classical: stricter checks to ensure that supplied intro,
  4357 dest and elim rules are well-formed; dest and elim rules must have at
  4358 least one premise.
  4359 
  4360 * Provers/classical: attributes dest/elim/intro take an optional
  4361 weight argument for the rule (just as the Pure versions).  Weights are
  4362 ignored by automated tools, but determine the search order of single
  4363 rule steps.
  4364 
  4365 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4366 where the body does not mention the bound variable.  Note that dummy
  4367 patterns implicitly depend on their context of bounds, which makes
  4368 "{_. _}" match any set comprehension as expected.  Potential
  4369 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4370 constant "_idtdummy" in the binding position.
  4371 
  4372 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4373 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4374 for example "A -> B" => "Pi A (%_. B)".
  4375 
  4376 * Pure: 'class_deps' command visualizes the subclass relation, using
  4377 the graph browser tool.
  4378 
  4379 * Pure: 'print_theory' now suppresses certain internal declarations by
  4380 default; use '!' option for full details.
  4381 
  4382 
  4383 *** HOL ***
  4384 
  4385 * Method "metis" proves goals by applying the Metis general-purpose
  4386 resolution prover (see also http://gilith.com/software/metis/).
  4387 Examples are in the directory MetisExamples.  WARNING: the
  4388 Isabelle/HOL-Metis integration does not yet work properly with
  4389 multi-threading.
  4390   
  4391 * Command 'sledgehammer' invokes external automatic theorem provers as
  4392 background processes.  It generates calls to the "metis" method if
  4393 successful. These can be pasted into the proof.  Users do not have to
  4394 wait for the automatic provers to return.  WARNING: does not really
  4395 work with multi-threading.
  4396 
  4397 * New "auto_quickcheck" feature tests outermost goal statements for
  4398 potential counter-examples.  Controlled by ML references
  4399 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4400 5000 milliseconds).  Fails silently if statements is outside of
  4401 executable fragment, or any other codgenerator problem occurs.
  4402 
  4403 * New constant "undefined" with axiom "undefined x = undefined".
  4404 
  4405 * Added class "HOL.eq", allowing for code generation with polymorphic
  4406 equality.
  4407 
  4408 * Some renaming of class constants due to canonical name prefixing in
  4409 the new 'class' package:
  4410 
  4411     HOL.abs ~> HOL.abs_class.abs
  4412     HOL.divide ~> HOL.divide_class.divide
  4413     0 ~> HOL.zero_class.zero
  4414     1 ~> HOL.one_class.one
  4415     op + ~> HOL.plus_class.plus
  4416     op - ~> HOL.minus_class.minus
  4417     uminus ~> HOL.minus_class.uminus
  4418     op * ~> HOL.times_class.times
  4419     op < ~> HOL.ord_class.less
  4420     op <= > HOL.ord_class.less_eq
  4421     Nat.power ~> Power.power_class.power
  4422     Nat.size ~> Nat.size_class.size
  4423     Numeral.number_of ~> Numeral.number_class.number_of
  4424     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4425     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4426     Orderings.min ~> Orderings.ord_class.min
  4427     Orderings.max ~> Orderings.ord_class.max
  4428     Divides.op div ~> Divides.div_class.div
  4429     Divides.op mod ~> Divides.div_class.mod
  4430     Divides.op dvd ~> Divides.div_class.dvd
  4431 
  4432 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4433 
  4434 a) User-defined constants using any of the names "plus", "minus",
  4435 "times", "less" or "less_eq". The standard syntax translations for
  4436 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4437 names.
  4438 
  4439 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4440 INCOMPATIBILITY: use more specific names.
  4441 
  4442 c) Permutative equations (e.g. "a + b = b + a")
  4443 Since the change of names also changes the order of terms, permutative
  4444 rewrite rules may get applied in a different order. Experience shows
  4445 that this is rarely the case (only two adaptions in the whole Isabelle
  4446 distribution).  INCOMPATIBILITY: rewrite proofs
  4447 
  4448 d) ML code directly refering to constant names
  4449 This in general only affects hand-written proof tactics, simprocs and
  4450 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4451 Consider using @{const_name} antiquotation.
  4452 
  4453 * New class "default" with associated constant "default".
  4454 
  4455 * Function "sgn" is now overloaded and available on int, real, complex
  4456 (and other numeric types), using class "sgn".  Two possible defs of
  4457 sgn are given as equational assumptions in the classes sgn_if and
  4458 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4459 INCOMPATIBILITY.
  4460 
  4461 * Locale "partial_order" now unified with class "order" (cf. theory
  4462 Orderings), added parameter "less".  INCOMPATIBILITY.
  4463 
  4464 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4465 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4466 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4467 
  4468 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4469 changed order of proof goals in instance proofs.
  4470 
  4471 * The transitivity reasoner for partial and linear orders is set up
  4472 for classes "order" and "linorder".  Instances of the reasoner are available
  4473 in all contexts importing or interpreting the corresponding locales.
  4474 Method "order" invokes the reasoner separately; the reasoner
  4475 is also integrated with the Simplifier as a solver.  Diagnostic
  4476 command 'print_orders' shows the available instances of the reasoner
  4477 in the current context.
  4478 
  4479 * Localized monotonicity predicate in theory "Orderings"; integrated
  4480 lemmas max_of_mono and min_of_mono with this predicate.
  4481 INCOMPATIBILITY.
  4482 
  4483 * Formulation of theorem "dense" changed slightly due to integration
  4484 with new class dense_linear_order.
  4485 
  4486 * Uniform lattice theory development in HOL.
  4487 
  4488     constants "meet" and "join" now named "inf" and "sup"
  4489     constant "Meet" now named "Inf"
  4490 
  4491     classes "meet_semilorder" and "join_semilorder" now named
  4492       "lower_semilattice" and "upper_semilattice"
  4493     class "lorder" now named "lattice"
  4494     class "comp_lat" now named "complete_lattice"
  4495 
  4496     Instantiation of lattice classes allows explicit definitions
  4497     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4498 
  4499   INCOMPATIBILITY.  Theorem renames:
  4500 
  4501     meet_left_le            ~> inf_le1
  4502     meet_right_le           ~> inf_le2
  4503     join_left_le            ~> sup_ge1
  4504     join_right_le           ~> sup_ge2
  4505     meet_join_le            ~> inf_sup_ord
  4506     le_meetI                ~> le_infI
  4507     join_leI                ~> le_supI
  4508     le_meet                 ~> le_inf_iff
  4509     le_join                 ~> ge_sup_conv
  4510     meet_idempotent         ~> inf_idem
  4511     join_idempotent         ~> sup_idem
  4512     meet_comm               ~> inf_commute
  4513     join_comm               ~> sup_commute
  4514     meet_leI1               ~> le_infI1
  4515     meet_leI2               ~> le_infI2
  4516     le_joinI1               ~> le_supI1
  4517     le_joinI2               ~> le_supI2
  4518     meet_assoc              ~> inf_assoc
  4519     join_assoc              ~> sup_assoc
  4520     meet_left_comm          ~> inf_left_commute
  4521     meet_left_idempotent    ~> inf_left_idem
  4522     join_left_comm          ~> sup_left_commute
  4523     join_left_idempotent    ~> sup_left_idem
  4524     meet_aci                ~> inf_aci
  4525     join_aci                ~> sup_aci
  4526     le_def_meet             ~> le_iff_inf
  4527     le_def_join             ~> le_iff_sup
  4528     join_absorp2            ~> sup_absorb2
  4529     join_absorp1            ~> sup_absorb1
  4530     meet_absorp1            ~> inf_absorb1
  4531     meet_absorp2            ~> inf_absorb2
  4532     meet_join_absorp        ~> inf_sup_absorb
  4533     join_meet_absorp        ~> sup_inf_absorb
  4534     distrib_join_le         ~> distrib_sup_le
  4535     distrib_meet_le         ~> distrib_inf_le
  4536 
  4537     add_meet_distrib_left   ~> add_inf_distrib_left
  4538     add_join_distrib_left   ~> add_sup_distrib_left
  4539     is_join_neg_meet        ~> is_join_neg_inf
  4540     is_meet_neg_join        ~> is_meet_neg_sup
  4541     add_meet_distrib_right  ~> add_inf_distrib_right
  4542     add_join_distrib_right  ~> add_sup_distrib_right
  4543     add_meet_join_distribs  ~> add_sup_inf_distribs
  4544     join_eq_neg_meet        ~> sup_eq_neg_inf
  4545     meet_eq_neg_join        ~> inf_eq_neg_sup
  4546     add_eq_meet_join        ~> add_eq_inf_sup
  4547     meet_0_imp_0            ~> inf_0_imp_0
  4548     join_0_imp_0            ~> sup_0_imp_0
  4549     meet_0_eq_0             ~> inf_0_eq_0
  4550     join_0_eq_0             ~> sup_0_eq_0
  4551     neg_meet_eq_join        ~> neg_inf_eq_sup
  4552     neg_join_eq_meet        ~> neg_sup_eq_inf
  4553     join_eq_if              ~> sup_eq_if
  4554 
  4555     mono_meet               ~> mono_inf
  4556     mono_join               ~> mono_sup
  4557     meet_bool_eq            ~> inf_bool_eq
  4558     join_bool_eq            ~> sup_bool_eq
  4559     meet_fun_eq             ~> inf_fun_eq
  4560     join_fun_eq             ~> sup_fun_eq
  4561     meet_set_eq             ~> inf_set_eq
  4562     join_set_eq             ~> sup_set_eq
  4563     meet1_iff               ~> inf1_iff
  4564     meet2_iff               ~> inf2_iff
  4565     meet1I                  ~> inf1I
  4566     meet2I                  ~> inf2I
  4567     meet1D1                 ~> inf1D1
  4568     meet2D1                 ~> inf2D1
  4569     meet1D2                 ~> inf1D2
  4570     meet2D2                 ~> inf2D2
  4571     meet1E                  ~> inf1E
  4572     meet2E                  ~> inf2E
  4573     join1_iff               ~> sup1_iff
  4574     join2_iff               ~> sup2_iff
  4575     join1I1                 ~> sup1I1
  4576     join2I1                 ~> sup2I1
  4577     join1I1                 ~> sup1I1
  4578     join2I2                 ~> sup1I2
  4579     join1CI                 ~> sup1CI
  4580     join2CI                 ~> sup2CI
  4581     join1E                  ~> sup1E
  4582     join2E                  ~> sup2E
  4583 
  4584     is_meet_Meet            ~> is_meet_Inf
  4585     Meet_bool_def           ~> Inf_bool_def
  4586     Meet_fun_def            ~> Inf_fun_def
  4587     Meet_greatest           ~> Inf_greatest
  4588     Meet_lower              ~> Inf_lower
  4589     Meet_set_def            ~> Inf_set_def
  4590 
  4591     Sup_def                 ~> Sup_Inf
  4592     Sup_bool_eq             ~> Sup_bool_def
  4593     Sup_fun_eq              ~> Sup_fun_def
  4594     Sup_set_eq              ~> Sup_set_def
  4595 
  4596     listsp_meetI            ~> listsp_infI
  4597     listsp_meet_eq          ~> listsp_inf_eq
  4598 
  4599     meet_min                ~> inf_min
  4600     join_max                ~> sup_max
  4601 
  4602 * Added syntactic class "size"; overloaded constant "size" now has
  4603 type "'a::size ==> bool"
  4604 
  4605 * Internal reorganisation of `size' of datatypes: size theorems
  4606 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4607 simplification rules by default!); theorems "prod.size" now named
  4608 "*.size".
  4609 
  4610 * Class "div" now inherits from class "times" rather than "type".
  4611 INCOMPATIBILITY.
  4612 
  4613 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4614 Linorder etc.  have disappeared; operations defined in terms of
  4615 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4616 
  4617 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4618 
  4619 * HOL-Word: New extensive library and type for generic, fixed size
  4620 machine words, with arithemtic, bit-wise, shifting and rotating
  4621 operations, reflection into int, nat, and bool lists, automation for
  4622 linear arithmetic (by automatic reflection into nat or int), including
  4623 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4624 arithmetic type classes, supporting automatic simplification of
  4625 numerals on all operations.
  4626 
  4627 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4628 
  4629 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4630 
  4631 * Code generator library theories:
  4632   - Code_Integer represents HOL integers by big integer literals in target
  4633     languages.
  4634   - Code_Char represents HOL characters by character literals in target
  4635     languages.
  4636   - Code_Char_chr like Code_Char, but also offers treatment of character
  4637     codes; includes Code_Integer.
  4638   - Executable_Set allows to generate code for finite sets using lists.
  4639   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4640     denominator).
  4641   - Executable_Real implements a subset of real numbers, namly those
  4642     representable by rational numbers.
  4643   - Efficient_Nat implements natural numbers by integers, which in general will
  4644     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4645     includes Code_Integer.
  4646   - Code_Index provides an additional datatype index which is mapped to
  4647     target-language built-in integers.
  4648   - Code_Message provides an additional datatype message_string which is isomorphic to
  4649     strings; messages are mapped to target-language strings.
  4650 
  4651 * New package for inductive predicates
  4652 
  4653   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4654 
  4655     inductive
  4656       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4657       for z_1 :: U_1 and ... and z_n :: U_m
  4658     where
  4659       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4660     | ...
  4661 
  4662   with full support for type-inference, rather than
  4663 
  4664     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4665 
  4666     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4667     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4668 
  4669     inductive "s z_1 ... z_m"
  4670     intros
  4671       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4672       ...
  4673 
  4674   For backward compatibility, there is a wrapper allowing inductive
  4675   sets to be defined with the new package via
  4676 
  4677     inductive_set
  4678       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4679       for z_1 :: U_1 and ... and z_n :: U_m
  4680     where
  4681       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4682     | ...
  4683 
  4684   or
  4685 
  4686     inductive_set
  4687       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4688       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4689       for z_1 :: U_1 and ... and z_n :: U_m
  4690     where
  4691       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4692     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4693     | ...
  4694 
  4695   if the additional syntax "p ..." is required.
  4696 
  4697   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4698   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4699 
  4700   INCOMPATIBILITIES:
  4701 
  4702   - Since declaration and definition of inductive sets or predicates
  4703     is no longer separated, abbreviations involving the newly
  4704     introduced sets or predicates must be specified together with the
  4705     introduction rules after the 'where' keyword (see above), rather
  4706     than before the actual inductive definition.
  4707 
  4708   - The variables in induction and elimination rules are now
  4709     quantified in the order of their occurrence in the introduction
  4710     rules, rather than in alphabetical order. Since this may break
  4711     some proofs, these proofs either have to be repaired, e.g. by
  4712     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4713     statements of the form
  4714 
  4715       case (rule_i a_i_1 ... a_i_{k_i})
  4716 
  4717     or the old order of quantification has to be restored by explicitly adding
  4718     meta-level quantifiers in the introduction rules, i.e.
  4719 
  4720       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4721 
  4722   - The format of the elimination rules is now
  4723 
  4724       p z_1 ... z_m x_1 ... x_n ==>
  4725         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4726         ==> ... ==> P
  4727 
  4728     for predicates and
  4729 
  4730       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4731         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4732         ==> ... ==> P
  4733 
  4734     for sets rather than
  4735 
  4736       x : s z_1 ... z_m ==>
  4737         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4738         ==> ... ==> P
  4739 
  4740     This may require terms in goals to be expanded to n-tuples
  4741     (e.g. using case_tac or simplification with the split_paired_all
  4742     rule) before the above elimination rule is applicable.
  4743 
  4744   - The elimination or case analysis rules for (mutually) inductive
  4745     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4746     list of rules "p_1_..._p_k.elims" is no longer available.
  4747 
  4748 * New package "function"/"fun" for general recursive functions,
  4749 supporting mutual and nested recursion, definitions in local contexts,
  4750 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4751 for small examples, and the separate tutorial on the function
  4752 package. The old recdef "package" is still available as before, but
  4753 users are encouraged to use the new package.
  4754 
  4755 * Method "lexicographic_order" automatically synthesizes termination
  4756 relations as lexicographic combinations of size measures. 
  4757 
  4758 * Case-expressions allow arbitrary constructor-patterns (including
  4759 "_") and take their order into account, like in functional
  4760 programming.  Internally, this is translated into nested
  4761 case-expressions; missing cases are added and mapped to the predefined
  4762 constant "undefined". In complicated cases printing may no longer show
  4763 the original input but the internal form. Lambda-abstractions allow
  4764 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4765 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4766 variable.
  4767 
  4768 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4769 is an abbreviation for "of_nat :: nat => int". The simplification
  4770 rules for "of_nat" have been changed to work like "int" did
  4771 previously.  Potential INCOMPATIBILITY:
  4772   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4773   - of_nat_diff and of_nat_mult are no longer default simp rules
  4774 
  4775 * Method "algebra" solves polynomial equations over (semi)rings using
  4776 Groebner bases. The (semi)ring structure is defined by locales and the
  4777 tool setup depends on that generic context. Installing the method for
  4778 a specific type involves instantiating the locale and possibly adding
  4779 declarations for computation on the coefficients.  The method is
  4780 already instantiated for natural numbers and for the axiomatic class
  4781 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4782 CALCULEMUS 2007 for the general principles underlying this
  4783 architecture of context-aware proof-tools.
  4784 
  4785 * Method "ferrack" implements quantifier elimination over
  4786 special-purpose dense linear orders using locales (analogous to
  4787 "algebra"). The method is already installed for class
  4788 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4789 rat, etc.
  4790 
  4791 * Former constant "List.op @" now named "List.append".  Use ML
  4792 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4793 circumvent possible incompatibilities when working on ML level.
  4794 
  4795 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4796 
  4797 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4798 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4799 
  4800 * New syntax for Haskell-like list comprehension (input only), eg.
  4801 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4802 
  4803 * The special syntax for function "filter" has changed from [x :
  4804 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4805 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4806 
  4807 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4808 defined on nat only, as an abbreviation for [a..<Suc b]
  4809 INCOMPATIBILITY.
  4810 
  4811 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4812 
  4813 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4814 
  4815 * New lemma collection field_simps (an extension of ring_simps) for
  4816 manipulating (in)equations involving division. Multiplies with all
  4817 denominators that can be proved to be non-zero (in equations) or
  4818 positive/negative (in inequations).
  4819 
  4820 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4821 have been improved and renamed to ring_simps, group_simps and
  4822 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4823 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4824 
  4825 * Theory Library/Commutative_Ring: switched from recdef to function
  4826 package; constants add, mul, pow now curried.  Infix syntax for
  4827 algebraic operations.
  4828 
  4829 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4830 INCOMPATIBILITY.
  4831 
  4832 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4833 INCOMPATIBILITY.
  4834 
  4835 * HOL/records: generalised field-update to take a function on the
  4836 field rather than the new value: r(|A := x|) is translated to A_update
  4837 (K x) r The K-combinator that is internally used is called K_record.
  4838 INCOMPATIBILITY: Usage of the plain update functions has to be
  4839 adapted.
  4840  
  4841 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4842 * x = 0, which are required for a semiring.  Richer structures do not
  4843 inherit from semiring_0 anymore, because this property is a theorem
  4844 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4845 there is more to prove, but this is mostly trivial.
  4846 
  4847 * Class "recpower" is generalized to arbitrary monoids, not just
  4848 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4849 commutativity or semiring properties additionally.
  4850 
  4851 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4852 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4853 better use 'abbreviation'.
  4854 
  4855 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4856 
  4857 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4858 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4859 significant changes for setting up numeral syntax for types:
  4860   - New constants Numeral.pred and Numeral.succ instead
  4861       of former Numeral.bin_pred and Numeral.bin_succ.
  4862   - Use integer operations instead of bin_add, bin_mult and so on.
  4863   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4864   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4865 
  4866 See src/HOL/Integ/IntArith.thy for an example setup.
  4867 
  4868 * Command 'normal_form' computes the normal form of a term that may
  4869 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4870 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4871 heavy-duty computations because the functions are compiled to ML
  4872 first.  Correspondingly, a method "normalization" is provided.  See
  4873 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4874 
  4875 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4876 25 like -->); output depends on the "iff" print_mode, the default is
  4877 "A = B" (with priority 50).
  4878 
  4879 * Relations less (<) and less_eq (<=) are also available on type bool.
  4880 Modified syntax to disallow nesting without explicit parentheses,
  4881 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4882 INCOMPATIBILITY.
  4883 
  4884 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4885 
  4886 * Relation composition operator "op O" now has precedence 75 and binds
  4887 stronger than union and intersection. INCOMPATIBILITY.
  4888 
  4889 * The old set interval syntax "{m..n(}" (and relatives) has been
  4890 removed.  Use "{m..<n}" (and relatives) instead.
  4891 
  4892 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4893 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4894 ``declare [[simproc del: neq]]''.
  4895 
  4896 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4897 True/False.
  4898 
  4899 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4900 
  4901 * Theorem setsum_mult renamed to setsum_right_distrib.
  4902 
  4903 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4904 ``rule'' method.
  4905 
  4906 * Reimplemented methods "sat" and "satx", with several improvements:
  4907 goals no longer need to be stated as "<prems> ==> False", equivalences
  4908 (i.e. "=" on type bool) are handled, variable names of the form
  4909 "lit_<n>" are no longer reserved, significant speedup.
  4910 
  4911 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4912 zChaff is still supported as well.
  4913 
  4914 * 'inductive' and 'datatype': provide projections of mutual rules,
  4915 bundled as foo_bar.inducts;
  4916 
  4917 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4918 Library.
  4919 
  4920 * Library: moved theory Accessible_Part to main HOL.
  4921 
  4922 * Library: added theory Coinductive_List of potentially infinite lists
  4923 as greatest fixed-point.
  4924 
  4925 * Library: added theory AssocList which implements (finite) maps as
  4926 association lists.
  4927 
  4928 * Method "evaluation" solves goals (i.e. a boolean expression)
  4929 efficiently by compiling it to ML.  The goal is "proved" (via an
  4930 oracle) if it evaluates to True.
  4931 
  4932 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4933 also when invoked by the simplifier.  This results in the Simplifier
  4934 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4935 Configuration option fast_arith_split_limit=0 recovers the old
  4936 behavior.
  4937 
  4938 * Support for hex (0x20) and binary (0b1001) numerals.
  4939 
  4940 * New method: reify eqs (t), where eqs are equations for an
  4941 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4942 parameter, computes a term s::'b and a list xs::'a list and proves the
  4943 theorem I xs s = t. This is also known as reification or quoting. The
  4944 resulting theorem is applied to the subgoal to substitute t with I xs
  4945 s.  If t is omitted, the subgoal itself is reified.
  4946 
  4947 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4948 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4949 where f is supposed to be a computable function (in the sense of code
  4950 generattion). The method uses reify to compute s and xs as above then
  4951 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4952 r and finally gets the theorem t = r, which is again applied to the
  4953 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4954 
  4955 * Reflection: Automatic reification now handels binding, an example is
  4956 available in src/HOL/ex/ReflectionEx.thy
  4957 
  4958 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4959 command 'statespace' that is similar to 'record', but introduces an
  4960 abstract specification based on the locale infrastructure instead of
  4961 HOL types.  This leads to extra flexibility in composing state spaces,
  4962 in particular multiple inheritance and renaming of components.
  4963 
  4964 
  4965 *** HOL-Complex ***
  4966 
  4967 * Hyperreal: Functions root and sqrt are now defined on negative real
  4968 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4969 Nonnegativity side conditions have been removed from many lemmas, so
  4970 that more subgoals may now be solved by simplification; potential
  4971 INCOMPATIBILITY.
  4972 
  4973 * Real: new type classes formalize real normed vector spaces and
  4974 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4975 and norm :: 'a => real.
  4976 
  4977 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4978 reals into other types. The overloaded constant Reals :: 'a set is now
  4979 defined as range of_real; potential INCOMPATIBILITY.
  4980 
  4981 * Real: proper support for ML code generation, including 'quickcheck'.
  4982 Reals are implemented as arbitrary precision rationals.
  4983 
  4984 * Hyperreal: Several constants that previously worked only for the
  4985 reals have been generalized, so they now work over arbitrary vector
  4986 spaces. Type annotations may need to be added in some cases; potential
  4987 INCOMPATIBILITY.
  4988 
  4989   Infinitesimal  :: ('a::real_normed_vector) star set
  4990   HFinite        :: ('a::real_normed_vector) star set
  4991   HInfinite      :: ('a::real_normed_vector) star set
  4992   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4993   monad          :: ('a::real_normed_vector) star => 'a star set
  4994   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4995   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4996   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4997   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4998   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4999   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  5000   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  5001   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  5002   sgn            :: 'a::real_normed_vector => 'a
  5003   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  5004 
  5005 * Complex: Some complex-specific constants are now abbreviations for
  5006 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  5007 hnorm.  Other constants have been entirely removed in favor of the
  5008 polymorphic versions (INCOMPATIBILITY):
  5009 
  5010   approx        <-- capprox
  5011   HFinite       <-- CFinite
  5012   HInfinite     <-- CInfinite
  5013   Infinitesimal <-- CInfinitesimal
  5014   monad         <-- cmonad
  5015   galaxy        <-- cgalaxy
  5016   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  5017   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  5018   (ns)deriv     <-- (ns)cderiv
  5019 
  5020 
  5021 *** HOL-Algebra ***
  5022 
  5023 * Formalisation of ideals and the quotient construction over rings.
  5024 
  5025 * Order and lattice theory no longer based on records.
  5026 INCOMPATIBILITY.
  5027 
  5028 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  5029 greatest_closed.  INCOMPATIBILITY.
  5030 
  5031 * Method algebra is now set up via an attribute.  For examples see
  5032 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  5033 of algebraic structures.
  5034 
  5035 * Renamed theory CRing to Ring.
  5036 
  5037 
  5038 *** HOL-Nominal ***
  5039 
  5040 * Substantial, yet incomplete support for nominal datatypes (binding
  5041 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  5042 src/HOL/Nominal/Examples.  Prospective users should consult
  5043 http://isabelle.in.tum.de/nominal/
  5044 
  5045 
  5046 *** ML ***
  5047 
  5048 * ML basics: just one true type int, which coincides with IntInf.int
  5049 (even on SML/NJ).
  5050 
  5051 * ML within Isar: antiquotations allow to embed statically-checked
  5052 formal entities in the source, referring to the context available at
  5053 compile-time.  For example:
  5054 
  5055 ML {* @{sort "{zero,one}"} *}
  5056 ML {* @{typ "'a => 'b"} *}
  5057 ML {* @{term "%x. x"} *}
  5058 ML {* @{prop "x == y"} *}
  5059 ML {* @{ctyp "'a => 'b"} *}
  5060 ML {* @{cterm "%x. x"} *}
  5061 ML {* @{cprop "x == y"} *}
  5062 ML {* @{thm asm_rl} *}
  5063 ML {* @{thms asm_rl} *}
  5064 ML {* @{type_name c} *}
  5065 ML {* @{type_syntax c} *}
  5066 ML {* @{const_name c} *}
  5067 ML {* @{const_syntax c} *}
  5068 ML {* @{context} *}
  5069 ML {* @{theory} *}
  5070 ML {* @{theory Pure} *}
  5071 ML {* @{theory_ref} *}
  5072 ML {* @{theory_ref Pure} *}
  5073 ML {* @{simpset} *}
  5074 ML {* @{claset} *}
  5075 ML {* @{clasimpset} *}
  5076 
  5077 The same works for sources being ``used'' within an Isar context.
  5078 
  5079 * ML in Isar: improved error reporting; extra verbosity with
  5080 ML_Context.trace enabled.
  5081 
  5082 * Pure/General/table.ML: the join operations now works via exceptions
  5083 DUP/SAME instead of type option. This is simpler in simple cases, and
  5084 admits slightly more efficient complex applications.
  5085 
  5086 * Pure: 'advanced' translation functions (parse_translation etc.) now
  5087 use Context.generic instead of just theory.
  5088 
  5089 * Pure: datatype Context.generic joins theory/Proof.context and
  5090 provides some facilities for code that works in either kind of
  5091 context, notably GenericDataFun for uniform theory and proof data.
  5092 
  5093 * Pure: simplified internal attribute type, which is now always
  5094 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  5095 local (Proof.context) attributes have been discontinued, while
  5096 minimizing code duplication. Thm.rule_attribute and
  5097 Thm.declaration_attribute build canonical attributes; see also structure
  5098 Context for further operations on Context.generic, notably
  5099 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  5100 declarations and definitions.
  5101 
  5102 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  5103 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  5104 init only required for impure data. INCOMPATIBILITY: empty really need
  5105 to be empty (no dependencies on theory content!)
  5106 
  5107 * Pure/kernel: consts certification ignores sort constraints given in
  5108 signature declarations. (This information is not relevant to the
  5109 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  5110 potential INCOMPATIBILITY.
  5111 
  5112 * Pure: axiomatic type classes are now purely definitional, with
  5113 explicit proofs of class axioms and super class relations performed
  5114 internally. See Pure/axclass.ML for the main internal interfaces --
  5115 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5116 AxClass.axiomatize_class/classrel/arity supersede
  5117 Sign.add_classes/classrel/arities.
  5118 
  5119 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5120 global/local versions on theory vs. Proof.context have been
  5121 discontinued; Attrib.syntax and Method.syntax have been adapted
  5122 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5123 attributes, methods, etc.
  5124 
  5125 * Pure: several functions of signature "... -> theory -> theory * ..."
  5126 have been reoriented to "... -> theory -> ... * theory" in order to
  5127 allow natural usage in combination with the ||>, ||>>, |-> and
  5128 fold_map combinators.
  5129 
  5130 * Pure: official theorem names (closed derivations) and additional
  5131 comments (tags) are now strictly separate.  Name hints -- which are
  5132 maintained as tags -- may be attached any time without affecting the
  5133 derivation.
  5134 
  5135 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5136 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5137 achieve the old behaviour.
  5138 
  5139 * Pure: the "Goal" constant is now called "prop", supporting a
  5140 slightly more general idea of ``protecting'' meta-level rule
  5141 statements.
  5142 
  5143 * Pure: Logic.(un)varify only works in a global context, which is now
  5144 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5145 Logic.legacy_(un)varify as temporary workaround.
  5146 
  5147 * Pure: structure Name provides scalable operations for generating
  5148 internal variable names, notably Name.variants etc.  This replaces
  5149 some popular functions from term.ML:
  5150 
  5151   Term.variant		->  Name.variant
  5152   Term.variantlist	->  Name.variant_list
  5153   Term.invent_names	->  Name.invent_list
  5154 
  5155 Note that low-level renaming rarely occurs in new code -- operations
  5156 from structure Variable are used instead (see below).
  5157 
  5158 * Pure: structure Variable provides fundamental operations for proper
  5159 treatment of fixed/schematic variables in a context.  For example,
  5160 Variable.import introduces fixes for schematics of given facts and
  5161 Variable.export reverses the effect (up to renaming) -- this replaces
  5162 various freeze_thaw operations.
  5163 
  5164 * Pure: structure Goal provides simple interfaces for
  5165 init/conclude/finish and tactical prove operations (replacing former
  5166 Tactic.prove).  Goal.prove is the canonical way to prove results
  5167 within a given context; Goal.prove_global is a degraded version for
  5168 theory level goals, including a global Drule.standard.  Note that
  5169 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5170 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5171 in a locale context).
  5172 
  5173 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5174 and type checking (Syntax.check_term etc.), with common combinations
  5175 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5176 which are considered legacy and await removal.
  5177 
  5178 * Pure/Syntax: generic interfaces for type unchecking
  5179 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5180 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5181 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5182 available for convenience, but refer to the very same operations using
  5183 a mere theory instead of a full context.
  5184 
  5185 * Isar: simplified treatment of user-level errors, using exception
  5186 ERROR of string uniformly.  Function error now merely raises ERROR,
  5187 without any side effect on output channels.  The Isar toplevel takes
  5188 care of proper display of ERROR exceptions.  ML code may use plain
  5189 handle/can/try; cat_error may be used to concatenate errors like this:
  5190 
  5191   ... handle ERROR msg => cat_error msg "..."
  5192 
  5193 Toplevel ML code (run directly or through the Isar toplevel) may be
  5194 embedded into the Isar toplevel with exception display/debug like
  5195 this:
  5196 
  5197   Isar.toplevel (fn () => ...)
  5198 
  5199 INCOMPATIBILITY, removed special transform_error facilities, removed
  5200 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5201 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5202 -- use plain ERROR instead.
  5203 
  5204 * Isar: theory setup now has type (theory -> theory), instead of a
  5205 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5206 
  5207 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5208 ProofContext.debug/verbose flags.
  5209 
  5210 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5211 theory before entering a proof state.  Transactions now always see a
  5212 quasi-functional intermediate checkpoint, both in interactive and
  5213 batch mode.
  5214 
  5215 * Isar: simplified interfaces for outer syntax.  Renamed
  5216 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5217 OuterSyntax.add_parsers -- this functionality is now included in
  5218 OuterSyntax.command etc.  INCOMPATIBILITY.
  5219 
  5220 * Simplifier: the simpset of a running simplification process now
  5221 contains a proof context (cf. Simplifier.the_context), which is the
  5222 very context that the initial simpset has been retrieved from (by
  5223 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5224 (solver, looper etc.) may depend on arbitrary proof data.
  5225 
  5226 * Simplifier.inherit_context inherits the proof context (plus the
  5227 local bounds) of the current simplification process; any simproc
  5228 etc. that calls the Simplifier recursively should do this!  Removed
  5229 former Simplifier.inherit_bounds, which is already included here --
  5230 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5231 specify an explicit context using Simplifier.context/theory_context.
  5232 
  5233 * Simplifier/Classical Reasoner: more abstract interfaces
  5234 change_simpset/claset for modifying the simpset/claset reference of a
  5235 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5236 INCOMPATIBILITY.
  5237 
  5238 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5239 "Trueprop" etc.
  5240 
  5241 
  5242 *** System ***
  5243 
  5244 * settings: the default heap location within ISABELLE_HOME_USER now
  5245 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5246 Isabelle installations.
  5247 
  5248 * isabelle-process: option -S (secure mode) disables some critical
  5249 operations, notably runtime compilation and evaluation of ML source
  5250 code.
  5251 
  5252 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5253 
  5254 * Support for parallel execution, using native multicore support of
  5255 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5256 independent theories, according to the given theory header
  5257 specifications. The maximum number of worker threads is specified via
  5258 usedir option -M or the "max-threads" setting in Proof General. A
  5259 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5260 to 6 on a 8-core machine.  User-code needs to observe certain
  5261 guidelines for thread-safe programming, see appendix A in the Isar
  5262 Implementation manual.
  5263 
  5264 
  5265 
  5266 New in Isabelle2005 (October 2005)
  5267 ----------------------------------
  5268 
  5269 *** General ***
  5270 
  5271 * Theory headers: the new header syntax for Isar theories is
  5272 
  5273   theory <name>
  5274   imports <theory1> ... <theoryN>
  5275   uses <file1> ... <fileM>
  5276   begin
  5277 
  5278 where the 'uses' part is optional.  The previous syntax
  5279 
  5280   theory <name> = <theory1> + ... + <theoryN>:
  5281 
  5282 will disappear in the next release.  Use isatool fixheaders to convert
  5283 existing theory files.  Note that there is no change in ancient
  5284 non-Isar theories now, but these will disappear soon.
  5285 
  5286 * Theory loader: parent theories can now also be referred to via
  5287 relative and absolute paths.
  5288 
  5289 * Command 'find_theorems' searches for a list of criteria instead of a
  5290 list of constants. Known criteria are: intro, elim, dest, name:string,
  5291 simp:term, and any term. Criteria can be preceded by '-' to select
  5292 theorems that do not match. Intro, elim, dest select theorems that
  5293 match the current goal, name:s selects theorems whose fully qualified
  5294 name contain s, and simp:term selects all simplification rules whose
  5295 lhs match term.  Any other term is interpreted as pattern and selects
  5296 all theorems matching the pattern. Available in ProofGeneral under
  5297 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5298 
  5299   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5300 
  5301 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5302 matching the current goal as introduction rule and not having "HOL."
  5303 in their name (i.e. not being defined in theory HOL).
  5304 
  5305 * Command 'thms_containing' has been discontinued in favour of
  5306 'find_theorems'; INCOMPATIBILITY.
  5307 
  5308 * Communication with Proof General is now 8bit clean, which means that
  5309 Unicode text in UTF-8 encoding may be used within theory texts (both
  5310 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5311 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5312 
  5313   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5314   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5315 
  5316 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5317 Classical Reasoner.  Typical big applications run around 2 times
  5318 faster.
  5319 
  5320 
  5321 *** Document preparation ***
  5322 
  5323 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5324 of raw sources.  Only those symbols that do not require additional
  5325 LaTeX packages (depending on comments in isabellesym.sty) are
  5326 displayed properly, everything else is left verbatim.  isatool display
  5327 and isatool print are used as front ends (these are subject to the
  5328 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5329 
  5330 * Command tags control specific markup of certain regions of text,
  5331 notably folding and hiding.  Predefined tags include "theory" (for
  5332 theory begin and end), "proof" for proof commands, and "ML" for
  5333 commands involving ML code; the additional tags "visible" and
  5334 "invisible" are unused by default.  Users may give explicit tag
  5335 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5336 interpretation of tags is determined by the LaTeX job during document
  5337 preparation: see option -V of isatool usedir, or options -n and -t of
  5338 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5339 \isadroptag.
  5340 
  5341 Several document versions may be produced at the same time via isatool
  5342 usedir (the generated index.html will link all of them).  Typical
  5343 specifications include ''-V document=theory,proof,ML'' to present
  5344 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5345 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5346 these parts without any formal replacement text.  The Isabelle site
  5347 default settings produce ''document'' and ''outline'' versions as
  5348 specified above.
  5349 
  5350 * Several new antiquotations:
  5351 
  5352   @{term_type term} prints a term with its type annotated;
  5353 
  5354   @{typeof term} prints the type of a term;
  5355 
  5356   @{const const} is the same as @{term const}, but checks that the
  5357   argument is a known logical constant;
  5358 
  5359   @{term_style style term} and @{thm_style style thm} print a term or
  5360   theorem applying a "style" to it
  5361 
  5362   @{ML text}
  5363 
  5364 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5365 definitions, equations, inequations etc., 'concl' printing only the
  5366 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5367 to print the specified premise.  TermStyle.add_style provides an ML
  5368 interface for introducing further styles.  See also the "LaTeX Sugar"
  5369 document practical applications.  The ML antiquotation prints
  5370 type-checked ML expressions verbatim.
  5371 
  5372 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5373 and 'text' support optional locale specification '(in loc)', which
  5374 specifies the default context for interpreting antiquotations.  For
  5375 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5376 
  5377 * Option 'locale=NAME' of antiquotations specifies an alternative
  5378 context interpreting the subsequent argument.  For example: @{thm
  5379 [locale=lattice] inf_assoc}.
  5380 
  5381 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5382 a proof context.
  5383 
  5384 * Proper output of antiquotations for theory commands involving a
  5385 proof context (such as 'locale' or 'theorem (in loc) ...').
  5386 
  5387 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5388 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5389 
  5390 * isatool usedir: new option -C (default true) controls whether option
  5391 -D should include a copy of the original document directory; -C false
  5392 prevents unwanted effects such as copying of administrative CVS data.
  5393 
  5394 
  5395 *** Pure ***
  5396 
  5397 * Considerably improved version of 'constdefs' command.  Now performs
  5398 automatic type-inference of declared constants; additional support for
  5399 local structure declarations (cf. locales and HOL records), see also
  5400 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5401 sequential dependencies of definitions within a single 'constdefs'
  5402 section; moreover, the declared name needs to be an identifier.  If
  5403 all fails, consider to fall back on 'consts' and 'defs' separately.
  5404 
  5405 * Improved indexed syntax and implicit structures.  First of all,
  5406 indexed syntax provides a notational device for subscripted
  5407 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5408 expressions.  Secondly, in a local context with structure
  5409 declarations, number indexes \<^sub>n or the empty index (default
  5410 number 1) refer to a certain fixed variable implicitly; option
  5411 show_structs controls printing of implicit structures.  Typical
  5412 applications of these concepts involve record types and locales.
  5413 
  5414 * New command 'no_syntax' removes grammar declarations (and
  5415 translations) resulting from the given syntax specification, which is
  5416 interpreted in the same manner as for the 'syntax' command.
  5417 
  5418 * 'Advanced' translation functions (parse_translation etc.) may depend
  5419 on the signature of the theory context being presently used for
  5420 parsing/printing, see also isar-ref manual.
  5421 
  5422 * Improved 'oracle' command provides a type-safe interface to turn an
  5423 ML expression of type theory -> T -> term into a primitive rule of
  5424 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5425 is already included here); see also FOL/ex/IffExample.thy;
  5426 INCOMPATIBILITY.
  5427 
  5428 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5429 before); "cI" is no longer bound, use "c.intro" instead.
  5430 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5431 axclasses vs. locales.
  5432 
  5433 * Improved internal renaming of symbolic identifiers -- attach primes
  5434 instead of base 26 numbers.
  5435 
  5436 * New flag show_question_marks controls printing of leading question
  5437 marks in schematic variable names.
  5438 
  5439 * In schematic variable names, *any* symbol following \<^isub> or
  5440 \<^isup> is now treated as part of the base name.  For example, the
  5441 following works without printing of awkward ".0" indexes:
  5442 
  5443   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5444     by simp
  5445 
  5446 * Inner syntax includes (*(*nested*) comments*).
  5447 
  5448 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5449 annotations as "(00...)".
  5450 
  5451 * Clear separation of logical types and nonterminals, where the latter
  5452 may only occur in 'syntax' specifications or type abbreviations.
  5453 Before that distinction was only partially implemented via type class
  5454 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5455 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5456 exotic syntax specifications may require further adaption
  5457 (e.g. Cube/Cube.thy).
  5458 
  5459 * Removed obsolete type class "logic", use the top sort {} instead.
  5460 Note that non-logical types should be declared as 'nonterminals'
  5461 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5462 specifications.
  5463 
  5464 * Attributes 'induct' and 'cases': type or set names may now be
  5465 locally fixed variables as well.
  5466 
  5467 * Simplifier: can now control the depth to which conditional rewriting
  5468 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5469 Limit.
  5470 
  5471 * Simplifier: simplification procedures may now take the current
  5472 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5473 interface), which is very useful for calling the Simplifier
  5474 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5475 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5476 low-level mk_simproc no longer applies Logic.varify internally, to
  5477 allow for use in a context of fixed variables.
  5478 
  5479 * thin_tac now works even if the assumption being deleted contains !!
  5480 or ==>.  More generally, erule now works even if the major premise of
  5481 the elimination rule contains !! or ==>.
  5482 
  5483 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5484 
  5485 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5486 from Pure, which contains all common declarations already.  Both
  5487 theories are defined via plain Isabelle/Isar .thy files.
  5488 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5489 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5490 use isatool fixcpure to adapt your theory and ML sources.
  5491 
  5492 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5493 selections of theorems in named facts via index ranges.
  5494 
  5495 * 'print_theorems': in theory mode, really print the difference
  5496 wrt. the last state (works for interactive theory development only),
  5497 in proof mode print all local facts (cf. 'print_facts');
  5498 
  5499 * 'hide': option '(open)' hides only base names.
  5500 
  5501 * More efficient treatment of intermediate checkpoints in interactive
  5502 theory development.
  5503 
  5504 * Code generator is now invoked via code_module (incremental code
  5505 generation) and code_library (modular code generation, ML structures
  5506 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5507 must be quoted when used as identifiers.
  5508 
  5509 * New 'value' command for reading, evaluating and printing terms using
  5510 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5511 quoted when used as identifier.
  5512 
  5513 
  5514 *** Locales ***
  5515 
  5516 * New commands for the interpretation of locale expressions in
  5517 theories (1), locales (2) and proof contexts (3).  These generate
  5518 proof obligations from the expression specification.  After the
  5519 obligations have been discharged, theorems of the expression are added
  5520 to the theory, target locale or proof context.  The synopsis of the
  5521 commands is a follows:
  5522 
  5523   (1) interpretation expr inst
  5524   (2) interpretation target < expr
  5525   (3) interpret expr inst
  5526 
  5527 Interpretation in theories and proof contexts require a parameter
  5528 instantiation of terms from the current context.  This is applied to
  5529 specifications and theorems of the interpreted expression.
  5530 Interpretation in locales only permits parameter renaming through the
  5531 locale expression.  Interpretation is smart in that interpretations
  5532 that are active already do not occur in proof obligations, neither are
  5533 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5534 inspect active interpretations of a particular locale.  For details,
  5535 see the Isar Reference manual.  Examples can be found in
  5536 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5537 
  5538 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5539 'interpret' instead.
  5540 
  5541 * New context element 'constrains' for adding type constraints to
  5542 parameters.
  5543 
  5544 * Context expressions: renaming of parameters with syntax
  5545 redeclaration.
  5546 
  5547 * Locale declaration: 'includes' disallowed.
  5548 
  5549 * Proper static binding of attribute syntax -- i.e. types / terms /
  5550 facts mentioned as arguments are always those of the locale definition
  5551 context, independently of the context of later invocations.  Moreover,
  5552 locale operations (renaming and type / term instantiation) are applied
  5553 to attribute arguments as expected.
  5554 
  5555 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5556 actual attributes; rare situations may require Attrib.attribute to
  5557 embed those attributes into Attrib.src that lack concrete syntax.
  5558 Attribute implementations need to cooperate properly with the static
  5559 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5560 Attrib.XXX_thm etc. already do the right thing without further
  5561 intervention.  Only unusual applications -- such as "where" or "of"
  5562 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5563 on the context and the facts involved -- may have to assign parsed
  5564 values to argument tokens explicitly.
  5565 
  5566 * Changed parameter management in theorem generation for long goal
  5567 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5568 theorem statement in rare situations.
  5569 
  5570 * Locale inspection command 'print_locale' omits notes elements.  Use
  5571 'print_locale!' to have them included in the output.
  5572 
  5573 
  5574 *** Provers ***
  5575 
  5576 * Provers/hypsubst.ML: improved version of the subst method, for
  5577 single-step rewriting: it now works in bound variable contexts. New is
  5578 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5579 rewrite a different subterm than the original subst method, which is
  5580 still available as 'simplesubst'.
  5581 
  5582 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5583 and quasi orders.
  5584 
  5585 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5586 reflexive-transitive closure of relations.
  5587 
  5588 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5589 limit (previously hard-coded with a value of 20) user-definable.
  5590 
  5591 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5592 is peformed already.  Object-logics merely need to finish their
  5593 initial simpset configuration as before.  INCOMPATIBILITY.
  5594 
  5595 
  5596 *** HOL ***
  5597 
  5598 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5599 
  5600   syntax (epsilon)
  5601     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5602 
  5603 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5604 and x-symbol; use option '-m epsilon' to get it actually printed.
  5605 Moreover, the mathematically important symbolic identifier \<epsilon>
  5606 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5607 
  5608 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5609 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5610 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5611 support corresponding Isar calculations.
  5612 
  5613 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5614 instead of ":".
  5615 
  5616 * theory SetInterval: changed the syntax for open intervals:
  5617 
  5618   Old       New
  5619   {..n(}    {..<n}
  5620   {)n..}    {n<..}
  5621   {m..n(}   {m..<n}
  5622   {)m..n}   {m<..n}
  5623   {)m..n(}  {m<..<n}
  5624 
  5625 The old syntax is still supported but will disappear in the next
  5626 release.  For conversion use the following Emacs search and replace
  5627 patterns (these are not perfect but work quite well):
  5628 
  5629   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5630   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5631 
  5632 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5633 equalities in commutative rings; method 'algebra' provides a generic
  5634 interface.
  5635 
  5636 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5637 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5638 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5639 be a tuple pattern.
  5640 
  5641 Some new syntax forms are available:
  5642 
  5643   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5644   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5645   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5646   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5647 
  5648 The latter form "\<Sum>x < k. e" used to be based on a separate
  5649 function "Summation", which has been discontinued.
  5650 
  5651 * theory Finite_Set: in structured induction proofs, the insert case
  5652 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5653 (insert F x)'.
  5654 
  5655 * The 'refute' command has been extended to support a much larger
  5656 fragment of HOL, including axiomatic type classes, constdefs and
  5657 typedefs, inductive datatypes and recursion.
  5658 
  5659 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5660 Requires zChaff with proof generation to be installed.  See
  5661 HOL/ex/SAT_Examples.thy for examples.
  5662 
  5663 * Datatype induction via method 'induct' now preserves the name of the
  5664 induction variable. For example, when proving P(xs::'a list) by
  5665 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5666 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5667 in unstructured proof scripts.
  5668 
  5669 * Reworked implementation of records.  Improved scalability for
  5670 records with many fields, avoiding performance problems for type
  5671 inference. Records are no longer composed of nested field types, but
  5672 of nested extension types. Therefore the record type only grows linear
  5673 in the number of extensions and not in the number of fields.  The
  5674 top-level (users) view on records is preserved.  Potential
  5675 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5676 old record representation. The type generated for a record is called
  5677 <record_name>_ext_type.
  5678 
  5679 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5680 proofs triggered by a record definition or a simproc (if
  5681 quick_and_dirty is enabled).  Definitions of large records can take
  5682 quite long.
  5683 
  5684 New simproc record_upd_simproc for simplification of multiple record
  5685 updates enabled by default.  Moreover, trivial updates are also
  5686 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5687 occasionally, since simplification is more powerful by default.
  5688 
  5689 * typedef: proper support for polymorphic sets, which contain extra
  5690 type-variables in the term.
  5691 
  5692 * Simplifier: automatically reasons about transitivity chains
  5693 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5694 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5695 old proofs break occasionally as simplification may now solve more
  5696 goals than previously.
  5697 
  5698 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5699 present.  Works for all partial orders (class "order"), in particular
  5700 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5701 just like y <= x.
  5702 
  5703 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5704 bound variable or a constant then the let is unfolded.  Otherwise
  5705 first a is simplified to b, and then f b is simplified to g. If
  5706 possible we abstract b from g arriving at "let x = b in h x",
  5707 otherwise we unfold the let and arrive at g.  The simproc can be
  5708 enabled/disabled by the reference use_let_simproc.  Potential
  5709 INCOMPATIBILITY since simplification is more powerful by default.
  5710 
  5711 * Classical reasoning: the meson method now accepts theorems as arguments.
  5712 
  5713 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5714 jobs to provide advice on the provability of subgoals.
  5715 
  5716 * Theory OrderedGroup and Ring_and_Field: various additions and
  5717 improvements to faciliate calculations involving equalities and
  5718 inequalities.
  5719 
  5720 The following theorems have been eliminated or modified
  5721 (INCOMPATIBILITY):
  5722 
  5723   abs_eq             now named abs_of_nonneg
  5724   abs_of_ge_0        now named abs_of_nonneg
  5725   abs_minus_eq       now named abs_of_nonpos
  5726   imp_abs_id         now named abs_of_nonneg
  5727   imp_abs_neg_id     now named abs_of_nonpos
  5728   mult_pos           now named mult_pos_pos
  5729   mult_pos_le        now named mult_nonneg_nonneg
  5730   mult_pos_neg_le    now named mult_nonneg_nonpos
  5731   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5732   mult_neg           now named mult_neg_neg
  5733   mult_neg_le        now named mult_nonpos_nonpos
  5734 
  5735 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5736      
  5737      zero_le_square
  5738      not_square_less_zero 
  5739 
  5740   The following lemmas have been deleted from Real/RealPow:
  5741   
  5742      realpow_zero_zero
  5743      realpow_two
  5744      realpow_less
  5745      zero_le_power
  5746      realpow_two_le
  5747      abs_realpow_two
  5748      realpow_two_abs     
  5749 
  5750 * Theory Parity: added rules for simplifying exponents.
  5751 
  5752 * Theory List:
  5753 
  5754 The following theorems have been eliminated or modified
  5755 (INCOMPATIBILITY):
  5756 
  5757   list_all_Nil       now named list_all.simps(1)
  5758   list_all_Cons      now named list_all.simps(2)
  5759   list_all_conv      now named list_all_iff
  5760   set_mem_eq         now named mem_iff
  5761 
  5762 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5763 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5764 
  5765 
  5766 *** HOL-Complex ***
  5767 
  5768 * Theory RealDef: better support for embedding natural numbers and
  5769 integers in the reals.
  5770 
  5771 The following theorems have been eliminated or modified
  5772 (INCOMPATIBILITY):
  5773 
  5774   exp_ge_add_one_self  now requires no hypotheses
  5775   real_of_int_add      reversed direction of equality (use [symmetric])
  5776   real_of_int_minus    reversed direction of equality (use [symmetric])
  5777   real_of_int_diff     reversed direction of equality (use [symmetric])
  5778   real_of_int_mult     reversed direction of equality (use [symmetric])
  5779 
  5780 * Theory RComplete: expanded support for floor and ceiling functions.
  5781 
  5782 * Theory Ln is new, with properties of the natural logarithm
  5783 
  5784 * Hyperreal: There is a new type constructor "star" for making
  5785 nonstandard types.  The old type names are now type synonyms:
  5786 
  5787   hypreal = real star
  5788   hypnat = nat star
  5789   hcomplex = complex star
  5790 
  5791 * Hyperreal: Many groups of similarly-defined constants have been
  5792 replaced by polymorphic versions (INCOMPATIBILITY):
  5793 
  5794   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5795 
  5796   starset      <-- starsetNat, starsetC
  5797   *s*          <-- *sNat*, *sc*
  5798   starset_n    <-- starsetNat_n, starsetC_n
  5799   *sn*         <-- *sNatn*, *scn*
  5800   InternalSets <-- InternalNatSets, InternalCSets
  5801 
  5802   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5803   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5804   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5805   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5806   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5807 
  5808 * Hyperreal: Many type-specific theorems have been removed in favor of
  5809 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5810 
  5811   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5812   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5813   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5814   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5815   right_minus <-- hypreal_add_minus
  5816   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5817   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5818   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5819   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5820   mult_1_right <-- hcomplex_mult_one_right
  5821   mult_zero_left <-- hcomplex_mult_zero_left
  5822   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5823   right_distrib <-- hypnat_add_mult_distrib2
  5824   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5825   right_inverse <-- hypreal_mult_inverse
  5826   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5827   order_refl <-- {hypreal,hypnat}_le_refl
  5828   order_trans <-- {hypreal,hypnat}_le_trans
  5829   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5830   order_less_le <-- {hypreal,hypnat}_less_le
  5831   linorder_linear <-- {hypreal,hypnat}_le_linear
  5832   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5833   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5834   add_nonneg_nonneg <-- hypreal_le_add_order
  5835 
  5836 * Hyperreal: Separate theorems having to do with type-specific
  5837 versions of constants have been merged into theorems that apply to the
  5838 new polymorphic constants (INCOMPATIBILITY):
  5839 
  5840   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5841   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5842   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5843   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5844   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5845   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5846   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5847   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5848   STAR_diff <-- {STAR,STARC}_diff
  5849   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5850     STARC_hcomplex_of_complex}_image_subset
  5851   starset_n_Un <-- starset{Nat,C}_n_Un
  5852   starset_n_Int <-- starset{Nat,C}_n_Int
  5853   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5854   starset_n_diff <-- starset{Nat,C}_n_diff
  5855   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5856   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5857   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5858   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5859   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5860   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5861   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5862   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5863   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5864   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5865   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5866   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5867   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5868   starfun_diff <-- starfun{C,RC,CR}_diff
  5869   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5870   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5871   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5872   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5873   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5874   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5875   starfun_Id <-- starfunC_Id
  5876   starfun_approx <-- starfun{Nat,CR}_approx
  5877   starfun_capprox <-- starfun{C,RC}_capprox
  5878   starfun_abs <-- starfunNat_rabs
  5879   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5880   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5881   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5882   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5883   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5884   starfun_add_approx <-- starfunCR_add_approx
  5885   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5886   starfun_divide <-- starfun{C,CR,RC}_divide
  5887   starfun_n <-- starfun{Nat,C}_n
  5888   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5889   starfun_n_add <-- starfun{Nat,C}_n_add
  5890   starfun_n_add_minus <-- starfunNat_n_add_minus
  5891   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5892   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5893   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5894 
  5895   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5896   star_n_minus <-- {hypreal,hcomplex}_minus
  5897   star_n_diff <-- {hypreal,hcomplex}_diff
  5898   star_n_mult <-- {hypreal,hcomplex}_mult
  5899   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5900   star_n_le <-- {hypreal,hypnat}_le
  5901   star_n_less <-- {hypreal,hypnat}_less
  5902   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5903   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5904   star_n_abs <-- hypreal_hrabs
  5905   star_n_divide <-- hcomplex_divide
  5906 
  5907   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5908   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5909   star_of_diff <-- hypreal_of_real_diff
  5910   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5911   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5912   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5913   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5914   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5915   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5916   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5917   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5918   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5919   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5920   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5921   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5922   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5923   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5924   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5925   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5926   star_of_power <-- hypreal_of_real_power
  5927   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5928 
  5929 * Hyperreal: new method "transfer" that implements the transfer
  5930 principle of nonstandard analysis. With a subgoal that mentions
  5931 nonstandard types like "'a star", the command "apply transfer"
  5932 replaces it with an equivalent one that mentions only standard types.
  5933 To be successful, all free variables must have standard types; non-
  5934 standard variables must have explicit universal quantifiers.
  5935 
  5936 * Hyperreal: A theory of Taylor series.
  5937 
  5938 
  5939 *** HOLCF ***
  5940 
  5941 * Discontinued special version of 'constdefs' (which used to support
  5942 continuous functions) in favor of the general Pure one with full
  5943 type-inference.
  5944 
  5945 * New simplification procedure for solving continuity conditions; it
  5946 is much faster on terms with many nested lambda abstractions (cubic
  5947 instead of exponential time).
  5948 
  5949 * New syntax for domain package: selector names are now optional.
  5950 Parentheses should be omitted unless argument is lazy, for example:
  5951 
  5952   domain 'a stream = cons "'a" (lazy "'a stream")
  5953 
  5954 * New command 'fixrec' for defining recursive functions with pattern
  5955 matching; defining multiple functions with mutual recursion is also
  5956 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5957 sinr, or any data constructor defined by the domain package. The given
  5958 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5959 syntax and examples.
  5960 
  5961 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5962 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5963 but the proof obligation additionally includes an admissibility
  5964 requirement. The packages generate instances of class cpo or pcpo,
  5965 with continuity and strictness theorems for Rep and Abs.
  5966 
  5967 * HOLCF: Many theorems have been renamed according to a more standard naming
  5968 scheme (INCOMPATIBILITY):
  5969 
  5970   foo_inject:  "foo$x = foo$y ==> x = y"
  5971   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5972   foo_less:    "(foo$x << foo$y) = (x << y)"
  5973   foo_strict:  "foo$UU = UU"
  5974   foo_defined: "... ==> foo$x ~= UU"
  5975   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5976 
  5977 
  5978 *** ZF ***
  5979 
  5980 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5981 including the First Isomorphism Theorem (on quotienting by the kernel
  5982 of a homomorphism).
  5983 
  5984 * ZF/Simplifier: install second copy of type solver that actually
  5985 makes use of TC rules declared to Isar proof contexts (or locales);
  5986 the old version is still required for ML proof scripts.
  5987 
  5988 
  5989 *** Cube ***
  5990 
  5991 * Converted to Isar theory format; use locales instead of axiomatic
  5992 theories.
  5993 
  5994 
  5995 *** ML ***
  5996 
  5997 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5998 for ||>, ||>>, |>>,
  5999 
  6000 * Pure/library.ML no longer defines its own option datatype, but uses
  6001 that of the SML basis, which has constructors NONE and SOME instead of
  6002 None and Some, as well as exception Option.Option instead of OPTION.
  6003 The functions the, if_none, is_some, is_none have been adapted
  6004 accordingly, while Option.map replaces apsome.
  6005 
  6006 * Pure/library.ML: the exception LIST has been given up in favour of
  6007 the standard exceptions Empty and Subscript, as well as
  6008 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  6009 superceded by the standard hd and tl functions etc.
  6010 
  6011 A number of basic list functions are no longer exported to the ML
  6012 toplevel, as they are variants of predefined functions.  The following
  6013 suggests how one can translate existing code:
  6014 
  6015     rev_append xs ys = List.revAppend (xs, ys)
  6016     nth_elem (i, xs) = List.nth (xs, i)
  6017     last_elem xs = List.last xs
  6018     flat xss = List.concat xss
  6019     seq fs = List.app fs
  6020     partition P xs = List.partition P xs
  6021     mapfilter f xs = List.mapPartial f xs
  6022 
  6023 * Pure/library.ML: several combinators for linear functional
  6024 transformations, notably reverse application and composition:
  6025 
  6026   x |> f                f #> g
  6027   (x, y) |-> f          f #-> g
  6028 
  6029 * Pure/library.ML: introduced/changed precedence of infix operators:
  6030 
  6031   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  6032   infix 2 ?;
  6033   infix 3 o oo ooo oooo;
  6034   infix 4 ~~ upto downto;
  6035 
  6036 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  6037 infix operators.
  6038 
  6039 * Pure/library.ML: natural list combinators fold, fold_rev, and
  6040 fold_map support linear functional transformations and nesting.  For
  6041 example:
  6042 
  6043   fold f [x1, ..., xN] y =
  6044     y |> f x1 |> ... |> f xN
  6045 
  6046   (fold o fold) f [xs1, ..., xsN] y =
  6047     y |> fold f xs1 |> ... |> fold f xsN
  6048 
  6049   fold f [x1, ..., xN] =
  6050     f x1 #> ... #> f xN
  6051 
  6052   (fold o fold) f [xs1, ..., xsN] =
  6053     fold f xs1 #> ... #> fold f xsN
  6054 
  6055 * Pure/library.ML: the following selectors on type 'a option are
  6056 available:
  6057 
  6058   the:               'a option -> 'a  (*partial*)
  6059   these:             'a option -> 'a  where 'a = 'b list
  6060   the_default: 'a -> 'a option -> 'a
  6061   the_list:          'a option -> 'a list
  6062 
  6063 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6064 basic operations for association lists, following natural argument
  6065 order; moreover the explicit equality predicate passed here avoids
  6066 potentially expensive polymorphic runtime equality checks.
  6067 The old functions may be expressed as follows:
  6068 
  6069   assoc = uncurry (AList.lookup (op =))
  6070   assocs = these oo AList.lookup (op =)
  6071   overwrite = uncurry (AList.update (op =)) o swap
  6072 
  6073 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  6074 
  6075   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  6076   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  6077 
  6078 replacing make_keylist and keyfilter (occassionally used)
  6079 Naive rewrites:
  6080 
  6081   make_keylist = AList.make
  6082   keyfilter = AList.find (op =)
  6083 
  6084 * eq_fst and eq_snd now take explicit equality parameter, thus
  6085   avoiding eqtypes. Naive rewrites:
  6086 
  6087     eq_fst = eq_fst (op =)
  6088     eq_snd = eq_snd (op =)
  6089 
  6090 * Removed deprecated apl and apr (rarely used).
  6091   Naive rewrites:
  6092 
  6093     apl (n, op) =>>= curry op n
  6094     apr (op, m) =>>= fn n => op (n, m)
  6095 
  6096 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  6097 provides a reasonably efficient light-weight implementation of sets as
  6098 lists.
  6099 
  6100 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  6101 few new operations; existing lookup and update are now curried to
  6102 follow natural argument order (for use with fold etc.);
  6103 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  6104 
  6105 * Pure/General: output via the Isabelle channels of
  6106 writeln/warning/error etc. is now passed through Output.output, with a
  6107 hook for arbitrary transformations depending on the print_mode
  6108 (cf. Output.add_mode -- the first active mode that provides a output
  6109 function wins).  Already formatted output may be embedded into further
  6110 text via Output.raw; the result of Pretty.string_of/str_of and derived
  6111 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6112 accommodate easy composition of diagnostic messages etc.  Programmers
  6113 rarely need to care about Output.output or Output.raw at all, with
  6114 some notable exceptions: Output.output is required when bypassing the
  6115 standard channels (writeln etc.), or in token translations to produce
  6116 properly formatted results; Output.raw is required when capturing
  6117 already output material that will eventually be presented to the user
  6118 a second time.  For the default print mode, both Output.output and
  6119 Output.raw have no effect.
  6120 
  6121 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6122 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6123 cumulative results are displayed at the end of a batch session.
  6124 
  6125 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6126 replaced by File.platform_path and File.shell_path (with appropriate
  6127 hooks).  This provides a clean interface for unusual systems where the
  6128 internal and external process view of file names are different.
  6129 
  6130 * Pure: more efficient orders for basic syntactic entities: added
  6131 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6132 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6133 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6134 orders now -- potential INCOMPATIBILITY for code that depends on a
  6135 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6136 Library.sort_strings on result).
  6137 
  6138 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6139 fold_types traverse types/terms from left to right, observing natural
  6140 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6141 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6142 
  6143 * Pure: name spaces have been refined, with significant changes of the
  6144 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6145 to extern(_table).  The plain name entry path is superceded by a
  6146 general 'naming' context, which also includes the 'policy' to produce
  6147 a fully qualified name and external accesses of a fully qualified
  6148 name; NameSpace.extend is superceded by context dependent
  6149 Sign.declare_name.  Several theory and proof context operations modify
  6150 the naming context.  Especially note Theory.restore_naming and
  6151 ProofContext.restore_naming to get back to a sane state; note that
  6152 Theory.add_path is no longer sufficient to recover from
  6153 Theory.absolute_path in particular.
  6154 
  6155 * Pure: new flags short_names (default false) and unique_names
  6156 (default true) for controlling output of qualified names.  If
  6157 short_names is set, names are printed unqualified.  If unique_names is
  6158 reset, the name prefix is reduced to the minimum required to achieve
  6159 the original result when interning again, even if there is an overlap
  6160 with earlier declarations.
  6161 
  6162 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6163 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6164 (useful for printing error messages).  INCOMPATIBILITY.
  6165 
  6166 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6167 Theory.theory are now identified, referring to the universal
  6168 Context.theory (see Pure/context.ML).  Actual signature and theory
  6169 content is managed as theory data.  The old code and interfaces were
  6170 spread over many files and structures; the new arrangement introduces
  6171 considerable INCOMPATIBILITY to gain more clarity:
  6172 
  6173   Context -- theory management operations (name, identity, inclusion,
  6174     parents, ancestors, merge, etc.), plus generic theory data;
  6175 
  6176   Sign -- logical signature and syntax operations (declaring consts,
  6177     types, etc.), plus certify/read for common entities;
  6178 
  6179   Theory -- logical theory operations (stating axioms, definitions,
  6180     oracles), plus a copy of logical signature operations (consts,
  6181     types, etc.); also a few basic management operations (Theory.copy,
  6182     Theory.merge, etc.)
  6183 
  6184 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6185 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6186 for convenience -- they merely return the theory.
  6187 
  6188 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6189 
  6190 * Pure: the Isar proof context type is already defined early in Pure
  6191 as Context.proof (note that ProofContext.context and Proof.context are
  6192 aliases, where the latter is the preferred name).  This enables other
  6193 Isabelle components to refer to that type even before Isar is present.
  6194 
  6195 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6196 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6197 any of these kinds.  For example, Sign.intern typeK is now
  6198 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6199 Theory.hide_types.  Also note that former
  6200 Theory.hide_classes/types/consts are now
  6201 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6202 internalize their arguments!  INCOMPATIBILITY.
  6203 
  6204 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6205 datatype thmref (with constructors Name and NameSelection) instead of
  6206 plain string -- INCOMPATIBILITY;
  6207 
  6208 * Pure: cases produced by proof methods specify options, where NONE
  6209 means to remove case bindings -- INCOMPATIBILITY in
  6210 (RAW_)METHOD_CASES.
  6211 
  6212 * Pure: the following operations retrieve axioms or theorems from a
  6213 theory node or theory hierarchy, respectively:
  6214 
  6215   Theory.axioms_of: theory -> (string * term) list
  6216   Theory.all_axioms_of: theory -> (string * term) list
  6217   PureThy.thms_of: theory -> (string * thm) list
  6218   PureThy.all_thms_of: theory -> (string * thm) list
  6219 
  6220 * Pure: print_tac now outputs the goal through the trace channel.
  6221 
  6222 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6223 Reference Toplevel.debug (default false) controls detailed printing
  6224 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6225 controls execution profiling -- set to 1 for time and 2 for space
  6226 (both increase the runtime).
  6227 
  6228 * Isar session: The initial use of ROOT.ML is now always timed,
  6229 i.e. the log will show the actual process times, in contrast to the
  6230 elapsed wall-clock time that the outer shell wrapper produces.
  6231 
  6232 * Simplifier: improved handling of bound variables (nameless
  6233 representation, avoid allocating new strings).  Simprocs that invoke
  6234 the Simplifier recursively should use Simplifier.inherit_bounds to
  6235 avoid local name clashes.  Failure to do so produces warnings
  6236 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6237 for further details.
  6238 
  6239 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6240 bindings for all theorems stored within a given theory; this may help
  6241 in porting non-Isar theories to Isar ones, while keeping ML proof
  6242 scripts for the time being.
  6243 
  6244 * ML operator HTML.with_charset specifies the charset begin used for
  6245 generated HTML files.  For example: