NEWS
author wenzelm
Fri Nov 11 22:05:18 2011 +0100 (2011-11-11)
changeset 45460 dcd02d1a25d7
parent 45427 fca432074fb2
child 45516 b2c8422833da
permissions -rw-r--r--
more tooltip content;
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** Pure ***
     8 
     9 * Obsolete command 'types' has been discontinued.  Use 'type_synonym'
    10 instead.  INCOMPATIBILITY.
    11 
    12 * Ancient code generator for SML and its commands 'code_module',
    13 'code_library', 'consts_code', 'types_code' have been discontinued.
    14 Use commands of the generic code generator instead. INCOMPATIBILITY.
    15 
    16 * Redundant attribute 'code_inline' has been discontinued. Use
    17 'code_unfold' instead. INCOMPATIBILITY.
    18 
    19 * Sort constraints are now propagated in simultaneous statements, just
    20 like type constraints.  INCOMPATIBILITY in rare situations, where
    21 distinct sorts used to be assigned accidentally.  For example:
    22 
    23   lemma "P (x::'a::foo)" and "Q (y::'a::bar)"  -- "now illegal"
    24 
    25   lemma "P (x::'a)" and "Q (y::'a::bar)"
    26     -- "now uniform 'a::bar instead of default sort for first occurence (!)"
    27 
    28 
    29 
    30 *** HOL ***
    31 
    32 * Clarified attribute "mono_set": pure declararation without modifying
    33 the result of the fact expression.
    34 
    35 * "Transitive_Closure.ntrancl": bounded transitive closure on
    36 relations.
    37 
    38 * Constant "Set.not_member" now qualifed.  INCOMPATIBILITY.
    39 
    40 * "sublists" moved to theory More_List.  INCOMPATIBILITY.
    41 
    42 * Theory Int: Discontinued many legacy theorems specific to type int.
    43 INCOMPATIBILITY, use the corresponding generic theorems instead.
    44 
    45   zminus_zminus ~> minus_minus
    46   zminus_0 ~> minus_zero
    47   zminus_zadd_distrib ~> minus_add_distrib
    48   zadd_commute ~> add_commute
    49   zadd_assoc ~> add_assoc
    50   zadd_left_commute ~> add_left_commute
    51   zadd_ac ~> add_ac
    52   zmult_ac ~> mult_ac
    53   zadd_0 ~> add_0_left
    54   zadd_0_right ~> add_0_right
    55   zadd_zminus_inverse2 ~> left_minus
    56   zmult_zminus ~> mult_minus_left
    57   zmult_commute ~> mult_commute
    58   zmult_assoc ~> mult_assoc
    59   zadd_zmult_distrib ~> left_distrib
    60   zadd_zmult_distrib2 ~> right_distrib
    61   zdiff_zmult_distrib ~> left_diff_distrib
    62   zdiff_zmult_distrib2 ~> right_diff_distrib
    63   zmult_1 ~> mult_1_left
    64   zmult_1_right ~> mult_1_right
    65   zle_refl ~> order_refl
    66   zle_trans ~> order_trans
    67   zle_antisym ~> order_antisym
    68   zle_linear ~> linorder_linear
    69   zless_linear ~> linorder_less_linear
    70   zadd_left_mono ~> add_left_mono
    71   zadd_strict_right_mono ~> add_strict_right_mono
    72   zadd_zless_mono ~> add_less_le_mono
    73   int_0_less_1 ~> zero_less_one
    74   int_0_neq_1 ~> zero_neq_one
    75   zless_le ~> less_le
    76   zpower_zadd_distrib ~> power_add
    77   zero_less_zpower_abs_iff ~> zero_less_power_abs_iff
    78   zero_le_zpower_abs ~> zero_le_power_abs
    79 
    80 * New "case_product" attribute to generate a case rule doing multiple
    81 case distinctions at the same time.  E.g.
    82 
    83   list.exhaust [case_product nat.exhaust]
    84 
    85 produces a rule which can be used to perform case distinction on both
    86 a list and a nat.
    87 
    88 
    89 * Nitpick:
    90   - Fixed infinite loop caused by the 'peephole_optim' option and affecting
    91     'rat' and 'real'.
    92 
    93 
    94 *** FOL ***
    95 
    96 * New "case_product" attribute (see HOL).
    97 
    98 
    99 *** ML ***
   100 
   101 * Structure Proof_Context follows standard naming scheme.  Old
   102 ProofContext has been discontinued.  INCOMPATIBILITY.
   103 
   104 * Refined Local_Theory.declaration {syntax, pervasive}, with subtle
   105 change of semantics: update is applied to auxiliary local theory
   106 context as well.
   107 
   108 
   109 
   110 New in Isabelle2011-1 (October 2011)
   111 ------------------------------------
   112 
   113 *** General ***
   114 
   115 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
   116 "isabelle jedit" or "ISABELLE_HOME/Isabelle" on the command line.
   117 
   118   - Management of multiple theory files directly from the editor
   119     buffer store -- bypassing the file-system (no requirement to save
   120     files for checking).
   121 
   122   - Markup of formal entities within the text buffer, with semantic
   123     highlighting, tooltips and hyperlinks to jump to defining source
   124     positions.
   125 
   126   - Improved text rendering, with sub/superscripts in the source
   127     buffer (including support for copy/paste wrt. output panel, HTML
   128     theory output and other non-Isabelle text boxes).
   129 
   130   - Refined scheduling of proof checking and printing of results,
   131     based on interactive editor view.  (Note: jEdit folding and
   132     narrowing allows to restrict buffer perspectives explicitly.)
   133 
   134   - Reduced CPU performance requirements, usable on machines with few
   135     cores.
   136 
   137   - Reduced memory requirements due to pruning of unused document
   138     versions (garbage collection).
   139 
   140 See also ~~/src/Tools/jEdit/README.html for further information,
   141 including some remaining limitations.
   142 
   143 * Theory loader: source files are exclusively located via the master
   144 directory of each theory node (where the .thy file itself resides).
   145 The global load path (such as src/HOL/Library) has been discontinued.
   146 Note that the path element ~~ may be used to reference theories in the
   147 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
   148 INCOMPATIBILITY.
   149 
   150 * Theory loader: source files are identified by content via SHA1
   151 digests.  Discontinued former path/modtime identification and optional
   152 ISABELLE_FILE_IDENT plugin scripts.
   153 
   154 * Parallelization of nested Isar proofs is subject to
   155 Goal.parallel_proofs_threshold (default 100).  See also isabelle
   156 usedir option -Q.
   157 
   158 * Name space: former unsynchronized references are now proper
   159 configuration options, with more conventional names:
   160 
   161   long_names   ~> names_long
   162   short_names  ~> names_short
   163   unique_names ~> names_unique
   164 
   165 Minor INCOMPATIBILITY, need to declare options in context like this:
   166 
   167   declare [[names_unique = false]]
   168 
   169 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
   170 that the result needs to be unique, which means fact specifications
   171 may have to be refined after enriching a proof context.
   172 
   173 * Attribute "case_names" has been refined: the assumptions in each case
   174 can be named now by following the case name with [name1 name2 ...].
   175 
   176 * Isabelle/Isar reference manual has been updated and extended:
   177   - "Synopsis" provides a catalog of main Isar language concepts.
   178   - Formal references in syntax diagrams, via @{rail} antiquotation.
   179   - Updated material from classic "ref" manual, notably about
   180     "Classical Reasoner".
   181 
   182 
   183 *** HOL ***
   184 
   185 * Class bot and top require underlying partial order rather than
   186 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
   187 
   188 * Class complete_lattice: generalized a couple of lemmas from sets;
   189 generalized theorems INF_cong and SUP_cong.  New type classes for
   190 complete boolean algebras and complete linear orders.  Lemmas
   191 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   192 class complete_linorder.
   193 
   194 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   195 Sup_fun_def, Inf_apply, Sup_apply.
   196 
   197 Removed redundant lemmas (the right hand side gives hints how to
   198 replace them for (metis ...), or (simp only: ...) proofs):
   199 
   200   Inf_singleton ~> Inf_insert [where A="{}", unfolded Inf_empty inf_top_right]
   201   Sup_singleton ~> Sup_insert [where A="{}", unfolded Sup_empty sup_bot_right]
   202   Inf_binary ~> Inf_insert, Inf_empty, and inf_top_right
   203   Sup_binary ~> Sup_insert, Sup_empty, and sup_bot_right
   204   Int_eq_Inter ~> Inf_insert, Inf_empty, and inf_top_right
   205   Un_eq_Union ~> Sup_insert, Sup_empty, and sup_bot_right
   206   Inter_def ~> INF_def, image_def
   207   Union_def ~> SUP_def, image_def
   208   INT_eq ~> INF_def, and image_def
   209   UN_eq ~> SUP_def, and image_def
   210   INF_subset ~> INF_superset_mono [OF _ order_refl]
   211 
   212 More consistent and comprehensive names:
   213 
   214   INTER_eq_Inter_image ~> INF_def
   215   UNION_eq_Union_image ~> SUP_def
   216   INFI_def ~> INF_def
   217   SUPR_def ~> SUP_def
   218   INF_leI ~> INF_lower
   219   INF_leI2 ~> INF_lower2
   220   le_INFI ~> INF_greatest
   221   le_SUPI ~> SUP_upper
   222   le_SUPI2 ~> SUP_upper2
   223   SUP_leI ~> SUP_least
   224   INFI_bool_eq ~> INF_bool_eq
   225   SUPR_bool_eq ~> SUP_bool_eq
   226   INFI_apply ~> INF_apply
   227   SUPR_apply ~> SUP_apply
   228   INTER_def ~> INTER_eq
   229   UNION_def ~> UNION_eq
   230 
   231 INCOMPATIBILITY.
   232 
   233 * Renamed theory Complete_Lattice to Complete_Lattices.
   234 INCOMPATIBILITY.
   235 
   236 * Theory Complete_Lattices: lemmas Inf_eq_top_iff, INF_eq_top_iff,
   237 INF_image, Inf_insert, INF_top, Inf_top_conv, INF_top_conv, SUP_bot,
   238 Sup_bot_conv, SUP_bot_conv, Sup_eq_top_iff, SUP_eq_top_iff, SUP_image,
   239 Sup_insert are now declared as [simp].  INCOMPATIBILITY.
   240 
   241 * Theory Lattice: lemmas compl_inf_bot, compl_le_comp_iff,
   242 compl_sup_top, inf_idem, inf_left_idem, inf_sup_absorb, sup_idem,
   243 sup_inf_absob, sup_left_idem are now declared as [simp].  Minor
   244 INCOMPATIBILITY.
   245 
   246 * Added syntactic classes "inf" and "sup" for the respective
   247 constants.  INCOMPATIBILITY: Changes in the argument order of the
   248 (mostly internal) locale predicates for some derived classes.
   249 
   250 * Theorem collections ball_simps and bex_simps do not contain theorems
   251 referring to UNION any longer; these have been moved to collection
   252 UN_ball_bex_simps.  INCOMPATIBILITY.
   253 
   254 * Theory Archimedean_Field: floor now is defined as parameter of a
   255 separate type class floor_ceiling.
   256 
   257 * Theory Finite_Set: more coherent development of fold_set locales:
   258 
   259     locale fun_left_comm ~> locale comp_fun_commute
   260     locale fun_left_comm_idem ~> locale comp_fun_idem
   261 
   262 Both use point-free characterization; interpretation proofs may need
   263 adjustment.  INCOMPATIBILITY.
   264 
   265 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   266 accordance with standard mathematical terminology. INCOMPATIBILITY.
   267 
   268 * Theory Complex_Main: The locale interpretations for the
   269 bounded_linear and bounded_bilinear locales have been removed, in
   270 order to reduce the number of duplicate lemmas. Users must use the
   271 original names for distributivity theorems, potential INCOMPATIBILITY.
   272 
   273   divide.add ~> add_divide_distrib
   274   divide.diff ~> diff_divide_distrib
   275   divide.setsum ~> setsum_divide_distrib
   276   mult.add_right ~> right_distrib
   277   mult.diff_right ~> right_diff_distrib
   278   mult_right.setsum ~> setsum_right_distrib
   279   mult_left.diff ~> left_diff_distrib
   280 
   281 * Theory Complex_Main: Several redundant theorems have been removed or
   282 replaced by more general versions. INCOMPATIBILITY.
   283 
   284   real_diff_def ~> minus_real_def
   285   real_divide_def ~> divide_real_def
   286   real_less_def ~> less_le
   287   real_abs_def ~> abs_real_def
   288   real_sgn_def ~> sgn_real_def
   289   real_mult_commute ~> mult_commute
   290   real_mult_assoc ~> mult_assoc
   291   real_mult_1 ~> mult_1_left
   292   real_add_mult_distrib ~> left_distrib
   293   real_zero_not_eq_one ~> zero_neq_one
   294   real_mult_inverse_left ~> left_inverse
   295   INVERSE_ZERO ~> inverse_zero
   296   real_le_refl ~> order_refl
   297   real_le_antisym ~> order_antisym
   298   real_le_trans ~> order_trans
   299   real_le_linear ~> linear
   300   real_le_eq_diff ~> le_iff_diff_le_0
   301   real_add_left_mono ~> add_left_mono
   302   real_mult_order ~> mult_pos_pos
   303   real_mult_less_mono2 ~> mult_strict_left_mono
   304   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   305   real_0_le_divide_iff ~> zero_le_divide_iff
   306   realpow_two_disj ~> power2_eq_iff
   307   real_squared_diff_one_factored ~> square_diff_one_factored
   308   realpow_two_diff ~> square_diff_square_factored
   309   reals_complete2 ~> complete_real
   310   real_sum_squared_expand ~> power2_sum
   311   exp_ln_eq ~> ln_unique
   312   expi_add ~> exp_add
   313   expi_zero ~> exp_zero
   314   lemma_DERIV_subst ~> DERIV_cong
   315   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   316   LIMSEQ_const ~> tendsto_const
   317   LIMSEQ_norm ~> tendsto_norm
   318   LIMSEQ_add ~> tendsto_add
   319   LIMSEQ_minus ~> tendsto_minus
   320   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   321   LIMSEQ_diff ~> tendsto_diff
   322   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   323   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   324   LIMSEQ_mult ~> tendsto_mult
   325   LIMSEQ_inverse ~> tendsto_inverse
   326   LIMSEQ_divide ~> tendsto_divide
   327   LIMSEQ_pow ~> tendsto_power
   328   LIMSEQ_setsum ~> tendsto_setsum
   329   LIMSEQ_setprod ~> tendsto_setprod
   330   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   331   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   332   LIMSEQ_imp_rabs ~> tendsto_rabs
   333   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   334   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   335   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   336   LIMSEQ_Complex ~> tendsto_Complex
   337   LIM_ident ~> tendsto_ident_at
   338   LIM_const ~> tendsto_const
   339   LIM_add ~> tendsto_add
   340   LIM_add_zero ~> tendsto_add_zero
   341   LIM_minus ~> tendsto_minus
   342   LIM_diff ~> tendsto_diff
   343   LIM_norm ~> tendsto_norm
   344   LIM_norm_zero ~> tendsto_norm_zero
   345   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   346   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   347   LIM_rabs ~> tendsto_rabs
   348   LIM_rabs_zero ~> tendsto_rabs_zero
   349   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   350   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   351   LIM_compose ~> tendsto_compose
   352   LIM_mult ~> tendsto_mult
   353   LIM_scaleR ~> tendsto_scaleR
   354   LIM_of_real ~> tendsto_of_real
   355   LIM_power ~> tendsto_power
   356   LIM_inverse ~> tendsto_inverse
   357   LIM_sgn ~> tendsto_sgn
   358   isCont_LIM_compose ~> isCont_tendsto_compose
   359   bounded_linear.LIM ~> bounded_linear.tendsto
   360   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   361   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   362   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   363   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   364   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   365   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   366 
   367 * Theory Complex_Main: The definition of infinite series was
   368 generalized.  Now it is defined on the type class {topological_space,
   369 comm_monoid_add}.  Hence it is useable also for extended real numbers.
   370 
   371 * Theory Complex_Main: The complex exponential function "expi" is now
   372 a type-constrained abbreviation for "exp :: complex => complex"; thus
   373 several polymorphic lemmas about "exp" are now applicable to "expi".
   374 
   375 * Code generation:
   376 
   377   - Theory Library/Code_Char_ord provides native ordering of
   378     characters in the target language.
   379 
   380   - Commands code_module and code_library are legacy, use export_code
   381     instead.
   382 
   383   - Method "evaluation" is legacy, use method "eval" instead.
   384 
   385   - Legacy evaluator "SML" is deactivated by default.  May be
   386     reactivated by the following theory command:
   387 
   388       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   389 
   390 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   391 
   392 * New proof method "induction" that gives induction hypotheses the
   393 name "IH", thus distinguishing them from further hypotheses that come
   394 from rule induction.  The latter are still called "hyps".  Method
   395 "induction" is a thin wrapper around "induct" and follows the same
   396 syntax.
   397 
   398 * Method "fastsimp" has been renamed to "fastforce", but "fastsimp" is
   399 still available as a legacy feature for some time.
   400 
   401 * Nitpick:
   402   - Added "need" and "total_consts" options.
   403   - Reintroduced "show_skolems" option by popular demand.
   404   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   405     INCOMPATIBILITY.
   406 
   407 * Sledgehammer:
   408   - Use quasi-sound (and efficient) translations by default.
   409   - Added support for the following provers: E-ToFoF, LEO-II,
   410     Satallax, SNARK, Waldmeister, and Z3 with TPTP syntax.
   411   - Automatically preplay and minimize proofs before showing them if
   412     this can be done within reasonable time.
   413   - sledgehammer available_provers ~> sledgehammer supported_provers.
   414     INCOMPATIBILITY.
   415   - Added "preplay_timeout", "slicing", "type_enc", "sound",
   416     "max_mono_iters", and "max_new_mono_instances" options.
   417   - Removed "explicit_apply" and "full_types" options as well as "Full
   418     Types" Proof General menu item. INCOMPATIBILITY.
   419 
   420 * Metis:
   421   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   422   - Obsoleted "metisFT" -- use "metis (full_types)" instead.
   423     INCOMPATIBILITY.
   424 
   425 * Command 'try':
   426   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
   427     "elim:" options. INCOMPATIBILITY.
   428   - Introduced 'try' that not only runs 'try_methods' but also
   429     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
   430 
   431 * Quickcheck:
   432   - Added "eval" option to evaluate terms for the found counterexample
   433     (currently only supported by the default (exhaustive) tester).
   434   - Added post-processing of terms to obtain readable counterexamples
   435     (currently only supported by the default (exhaustive) tester).
   436   - New counterexample generator quickcheck[narrowing] enables
   437     narrowing-based testing.  Requires the Glasgow Haskell compiler
   438     with its installation location defined in the Isabelle settings
   439     environment as ISABELLE_GHC.
   440   - Removed quickcheck tester "SML" based on the SML code generator
   441     (formly in HOL/Library).
   442 
   443 * Function package: discontinued option "tailrec".  INCOMPATIBILITY,
   444 use 'partial_function' instead.
   445 
   446 * Theory Library/Extended_Reals replaces now the positive extended
   447 reals found in probability theory. This file is extended by
   448 Multivariate_Analysis/Extended_Real_Limits.
   449 
   450 * Theory Library/Old_Recdef: old 'recdef' package has been moved here,
   451 from where it must be imported explicitly if it is really required.
   452 INCOMPATIBILITY.
   453 
   454 * Theory Library/Wfrec: well-founded recursion combinator "wfrec" has
   455 been moved here.  INCOMPATIBILITY.
   456 
   457 * Theory Library/Saturated provides type of numbers with saturated
   458 arithmetic.
   459 
   460 * Theory Library/Product_Lattice defines a pointwise ordering for the
   461 product type 'a * 'b, and provides instance proofs for various order
   462 and lattice type classes.
   463 
   464 * Theory Library/Countable now provides the "countable_datatype" proof
   465 method for proving "countable" class instances for datatypes.
   466 
   467 * Theory Library/Cset_Monad allows do notation for computable sets
   468 (cset) via the generic monad ad-hoc overloading facility.
   469 
   470 * Library: Theories of common data structures are split into theories
   471 for implementation, an invariant-ensuring type, and connection to an
   472 abstract type. INCOMPATIBILITY.
   473 
   474   - RBT is split into RBT and RBT_Mapping.
   475   - AssocList is split and renamed into AList and AList_Mapping.
   476   - DList is split into DList_Impl, DList, and DList_Cset.
   477   - Cset is split into Cset and List_Cset.
   478 
   479 * Theory Library/Nat_Infinity has been renamed to
   480 Library/Extended_Nat, with name changes of the following types and
   481 constants:
   482 
   483   type inat   ~> type enat
   484   Fin         ~> enat
   485   Infty       ~> infinity (overloaded)
   486   iSuc        ~> eSuc
   487   the_Fin     ~> the_enat
   488 
   489 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   490 been renamed accordingly. INCOMPATIBILITY.
   491 
   492 * Session Multivariate_Analysis: The euclidean_space type class now
   493 fixes a constant "Basis :: 'a set" consisting of the standard
   494 orthonormal basis for the type. Users now have the option of
   495 quantifying over this set instead of using the "basis" function, e.g.
   496 "ALL x:Basis. P x" vs "ALL i<DIM('a). P (basis i)".
   497 
   498 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   499 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   500 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   501 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   502 changed to match. Definition theorems for overloaded constants now use
   503 the standard "foo_vec_def" naming scheme. A few other theorems have
   504 been renamed as follows (INCOMPATIBILITY):
   505 
   506   Cart_eq          ~> vec_eq_iff
   507   dist_nth_le_cart ~> dist_vec_nth_le
   508   tendsto_vector   ~> vec_tendstoI
   509   Cauchy_vector    ~> vec_CauchyI
   510 
   511 * Session Multivariate_Analysis: Several duplicate theorems have been
   512 removed, and other theorems have been renamed or replaced with more
   513 general versions. INCOMPATIBILITY.
   514 
   515   finite_choice ~> finite_set_choice
   516   eventually_conjI ~> eventually_conj
   517   eventually_and ~> eventually_conj_iff
   518   eventually_false ~> eventually_False
   519   setsum_norm ~> norm_setsum
   520   Lim_sequentially ~> LIMSEQ_def
   521   Lim_ident_at ~> LIM_ident
   522   Lim_const ~> tendsto_const
   523   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   524   Lim_neg ~> tendsto_minus
   525   Lim_add ~> tendsto_add
   526   Lim_sub ~> tendsto_diff
   527   Lim_mul ~> tendsto_scaleR
   528   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   529   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   530   Lim_linear ~> bounded_linear.tendsto
   531   Lim_component ~> tendsto_euclidean_component
   532   Lim_component_cart ~> tendsto_vec_nth
   533   Lim_inner ~> tendsto_inner [OF tendsto_const]
   534   dot_lsum ~> inner_setsum_left
   535   dot_rsum ~> inner_setsum_right
   536   continuous_cmul ~> continuous_scaleR [OF continuous_const]
   537   continuous_neg ~> continuous_minus
   538   continuous_sub ~> continuous_diff
   539   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
   540   continuous_mul ~> continuous_scaleR
   541   continuous_inv ~> continuous_inverse
   542   continuous_at_within_inv ~> continuous_at_within_inverse
   543   continuous_at_inv ~> continuous_at_inverse
   544   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
   545   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
   546   continuous_at_component ~> continuous_component [OF continuous_at_id]
   547   continuous_on_neg ~> continuous_on_minus
   548   continuous_on_sub ~> continuous_on_diff
   549   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   550   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   551   continuous_on_mul ~> continuous_on_scaleR
   552   continuous_on_mul_real ~> continuous_on_mult
   553   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   554   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
   555   continuous_on_inverse ~> continuous_on_inv
   556   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
   557   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
   558   subset_interior ~> interior_mono
   559   subset_closure ~> closure_mono
   560   closure_univ ~> closure_UNIV
   561   real_arch_lt ~> reals_Archimedean2
   562   real_arch ~> reals_Archimedean3
   563   real_abs_norm ~> abs_norm_cancel
   564   real_abs_sub_norm ~> norm_triangle_ineq3
   565   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
   566 
   567 * Session HOL-Probability:
   568   - Caratheodory's extension lemma is now proved for ring_of_sets.
   569   - Infinite products of probability measures are now available.
   570   - Sigma closure is independent, if the generator is independent
   571   - Use extended reals instead of positive extended
   572     reals. INCOMPATIBILITY.
   573 
   574 * Session HOLCF: Discontinued legacy theorem names, INCOMPATIBILITY.
   575 
   576   expand_fun_below ~> fun_below_iff
   577   below_fun_ext ~> fun_belowI
   578   expand_cfun_eq ~> cfun_eq_iff
   579   ext_cfun ~> cfun_eqI
   580   expand_cfun_below ~> cfun_below_iff
   581   below_cfun_ext ~> cfun_belowI
   582   monofun_fun_fun ~> fun_belowD
   583   monofun_fun_arg ~> monofunE
   584   monofun_lub_fun ~> adm_monofun [THEN admD]
   585   cont_lub_fun ~> adm_cont [THEN admD]
   586   cont2cont_Rep_CFun ~> cont2cont_APP
   587   cont_Rep_CFun_app ~> cont_APP_app
   588   cont_Rep_CFun_app_app ~> cont_APP_app_app
   589   cont_cfun_fun ~> cont_Rep_cfun1 [THEN contE]
   590   cont_cfun_arg ~> cont_Rep_cfun2 [THEN contE]
   591   contlub_cfun ~> lub_APP [symmetric]
   592   contlub_LAM ~> lub_LAM [symmetric]
   593   thelubI ~> lub_eqI
   594   UU_I ~> bottomI
   595   lift_distinct1 ~> lift.distinct(1)
   596   lift_distinct2 ~> lift.distinct(2)
   597   Def_not_UU ~> lift.distinct(2)
   598   Def_inject ~> lift.inject
   599   below_UU_iff ~> below_bottom_iff
   600   eq_UU_iff ~> eq_bottom_iff
   601 
   602 
   603 *** Document preparation ***
   604 
   605 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   606 isar-ref manual, both for description and actual application of the
   607 same.
   608 
   609 * Antiquotation @{value} evaluates the given term and presents its
   610 result.
   611 
   612 * Antiquotations: term style "isub" provides ad-hoc conversion of
   613 variables x1, y23 into subscripted form x\<^isub>1,
   614 y\<^isub>2\<^isub>3.
   615 
   616 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   617 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   618 
   619 * Localized \isabellestyle switch can be used within blocks or groups
   620 like this:
   621 
   622   \isabellestyle{it}  %preferred default
   623   {\isabellestylett @{text "typewriter stuff"}}
   624 
   625 * Discontinued special treatment of hard tabulators.  Implicit
   626 tab-width is now defined as 1.  Potential INCOMPATIBILITY for visual
   627 layouts.
   628 
   629 
   630 *** ML ***
   631 
   632 * The inner syntax of sort/type/term/prop supports inlined YXML
   633 representations within quoted string tokens.  By encoding logical
   634 entities via Term_XML (in ML or Scala) concrete syntax can be
   635 bypassed, which is particularly useful for producing bits of text
   636 under external program control.
   637 
   638 * Antiquotations for ML and document preparation are managed as theory
   639 data, which requires explicit setup.
   640 
   641 * Isabelle_Process.is_active allows tools to check if the official
   642 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   643 (better known as Proof General).
   644 
   645 * Structure Proof_Context follows standard naming scheme.  Old
   646 ProofContext is still available for some time as legacy alias.
   647 
   648 * Structure Timing provides various operations for timing; supersedes
   649 former start_timing/end_timing etc.
   650 
   651 * Path.print is the official way to show file-system paths to users
   652 (including quotes etc.).
   653 
   654 * Inner syntax: identifiers in parse trees of generic categories
   655 "logic", "aprop", "idt" etc. carry position information (disguised as
   656 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   657 translations that choke on unexpected type constraints.  Positions can
   658 be stripped in ML translations via Syntax.strip_positions /
   659 Syntax.strip_positions_ast, or via the syntax constant
   660 "_strip_positions" within parse trees.  As last resort, positions can
   661 be disabled via the configuration option Syntax.positions, which is
   662 called "syntax_positions" in Isar attribute syntax.
   663 
   664 * Discontinued special status of various ML structures that contribute
   665 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   666 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   667 refer directly to Ast.Constant, Lexicon.is_identifier,
   668 Syntax_Trans.mk_binder_tr etc.
   669 
   670 * Typed print translation: discontinued show_sorts argument, which is
   671 already available via context of "advanced" translation.
   672 
   673 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   674 goal states; body tactic needs to address all subgoals uniformly.
   675 
   676 * Slightly more special eq_list/eq_set, with shortcut involving
   677 pointer equality (assumes that eq relation is reflexive).
   678 
   679 * Classical tactics use proper Proof.context instead of historic types
   680 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   681 operate directly on Proof.context.  Raw type claset retains its use as
   682 snapshot of the classical context, which can be recovered via
   683 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   684 INCOMPATIBILITY, classical tactics and derived proof methods require
   685 proper Proof.context.
   686 
   687 
   688 *** System ***
   689 
   690 * Discontinued support for Poly/ML 5.2, which was the last version
   691 without proper multithreading and TimeLimit implementation.
   692 
   693 * Discontinued old lib/scripts/polyml-platform, which has been
   694 obsolete since Isabelle2009-2.
   695 
   696 * Various optional external tools are referenced more robustly and
   697 uniformly by explicit Isabelle settings as follows:
   698 
   699   ISABELLE_CSDP   (formerly CSDP_EXE)
   700   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
   701   ISABELLE_OCAML  (formerly EXEC_OCAML)
   702   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
   703   ISABELLE_YAP    (formerly EXEC_YAP)
   704 
   705 Note that automated detection from the file-system or search path has
   706 been discontinued.  INCOMPATIBILITY.
   707 
   708 * Scala layer provides JVM method invocation service for static
   709 methods of type (String)String, see Invoke_Scala.method in ML.  For
   710 example:
   711 
   712   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   713 
   714 Together with YXML.string_of_body/parse_body and XML.Encode/Decode
   715 this allows to pass structured values between ML and Scala.
   716 
   717 * The IsabelleText fonts includes some further glyphs to support the
   718 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
   719 installed a local copy (which is normally *not* required) need to
   720 delete or update it from ~~/lib/fonts/.
   721 
   722 
   723 
   724 New in Isabelle2011 (January 2011)
   725 ----------------------------------
   726 
   727 *** General ***
   728 
   729 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   730 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   731 useful tooltips and hyperlinks produced from its static analysis.  The
   732 bundled component provides an executable Isabelle tool that can be run
   733 like this:
   734 
   735   Isabelle2011/bin/isabelle jedit
   736 
   737 * Significantly improved Isabelle/Isar implementation manual.
   738 
   739 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   740 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   741 while the default heap location within that directory lacks that extra
   742 suffix.  This isolates multiple Isabelle installations from each
   743 other, avoiding problems with old settings in new versions.
   744 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   745 
   746 * Source files are always encoded as UTF-8, instead of old-fashioned
   747 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   748 the following package declarations:
   749 
   750   \usepackage[utf8]{inputenc}
   751   \usepackage{textcomp}
   752 
   753 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   754 a Unicode character is treated as a single symbol, not a sequence of
   755 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   756 contain symbols without further backslash escapes, Unicode can now be
   757 used here as well.  Recall that Symbol.explode in ML provides a
   758 consistent view on symbols, while raw explode (or String.explode)
   759 merely give a byte-oriented representation.
   760 
   761 * Theory loader: source files are primarily located via the master
   762 directory of each theory node (where the .thy file itself resides).
   763 The global load path is still partially available as legacy feature.
   764 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   765 explicit paths, relatively to the theory.
   766 
   767 * Special treatment of ML file names has been discontinued.
   768 Historically, optional extensions .ML or .sml were added on demand --
   769 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   770 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   771 
   772 * Various options that affect pretty printing etc. are now properly
   773 handled within the context via configuration options, instead of
   774 unsynchronized references or print modes.  There are both ML Config.T
   775 entities and Isar declaration attributes to access these.
   776 
   777   ML (Config.T)                 Isar (attribute)
   778 
   779   eta_contract                  eta_contract
   780   show_brackets                 show_brackets
   781   show_sorts                    show_sorts
   782   show_types                    show_types
   783   show_question_marks           show_question_marks
   784   show_consts                   show_consts
   785   show_abbrevs                  show_abbrevs
   786 
   787   Syntax.ast_trace              syntax_ast_trace
   788   Syntax.ast_stat               syntax_ast_stat
   789   Syntax.ambiguity_level        syntax_ambiguity_level
   790 
   791   Goal_Display.goals_limit      goals_limit
   792   Goal_Display.show_main_goal   show_main_goal
   793 
   794   Method.rule_trace             rule_trace
   795 
   796   Thy_Output.display            thy_output_display
   797   Thy_Output.quotes             thy_output_quotes
   798   Thy_Output.indent             thy_output_indent
   799   Thy_Output.source             thy_output_source
   800   Thy_Output.break              thy_output_break
   801 
   802 Note that corresponding "..._default" references in ML may only be
   803 changed globally at the ROOT session setup, but *not* within a theory.
   804 The option "show_abbrevs" supersedes the former print mode
   805 "no_abbrevs" with inverted meaning.
   806 
   807 * More systematic naming of some configuration options.
   808 INCOMPATIBILITY.
   809 
   810   trace_simp  ~>  simp_trace
   811   debug_simp  ~>  simp_debug
   812 
   813 * Support for real valued configuration options, using simplistic
   814 floating-point notation that coincides with the inner syntax for
   815 float_token.
   816 
   817 * Support for real valued preferences (with approximative PGIP type):
   818 front-ends need to accept "pgint" values in float notation.
   819 INCOMPATIBILITY.
   820 
   821 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   822 DejaVu Sans.
   823 
   824 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   825 
   826 
   827 *** Pure ***
   828 
   829 * Command 'type_synonym' (with single argument) replaces somewhat
   830 outdated 'types', which is still available as legacy feature for some
   831 time.
   832 
   833 * Command 'nonterminal' (with 'and' separated list of arguments)
   834 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   835 
   836 * Command 'notepad' replaces former 'example_proof' for
   837 experimentation in Isar without any result.  INCOMPATIBILITY.
   838 
   839 * Locale interpretation commands 'interpret' and 'sublocale' accept
   840 lists of equations to map definitions in a locale to appropriate
   841 entities in the context of the interpretation.  The 'interpretation'
   842 command already provided this functionality.
   843 
   844 * Diagnostic command 'print_dependencies' prints the locale instances
   845 that would be activated if the specified expression was interpreted in
   846 the current context.  Variant "print_dependencies!" assumes a context
   847 without interpretations.
   848 
   849 * Diagnostic command 'print_interps' prints interpretations in proofs
   850 in addition to interpretations in theories.
   851 
   852 * Discontinued obsolete 'global' and 'local' commands to manipulate
   853 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   854 Sign.root_path and Sign.local_path may be applied directly where this
   855 feature is still required for historical reasons.
   856 
   857 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   858 'definition' instead.
   859 
   860 * The "prems" fact, which refers to the accidental collection of
   861 foundational premises in the context, is now explicitly marked as
   862 legacy feature and will be discontinued soon.  Consider using "assms"
   863 of the head statement or reference facts by explicit names.
   864 
   865 * Document antiquotations @{class} and @{type} print classes and type
   866 constructors.
   867 
   868 * Document antiquotation @{file} checks file/directory entries within
   869 the local file system.
   870 
   871 
   872 *** HOL ***
   873 
   874 * Coercive subtyping: functions can be declared as coercions and type
   875 inference will add them as necessary upon input of a term.  Theory
   876 Complex_Main declares real :: nat => real and real :: int => real as
   877 coercions. A coercion function f is declared like this:
   878 
   879   declare [[coercion f]]
   880 
   881 To lift coercions through type constructors (e.g. from nat => real to
   882 nat list => real list), map functions can be declared, e.g.
   883 
   884   declare [[coercion_map map]]
   885 
   886 Currently coercion inference is activated only in theories including
   887 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   888 the configuration option "coercion_enabled", e.g. it can be enabled in
   889 other theories like this:
   890 
   891   declare [[coercion_enabled]]
   892 
   893 * Command 'partial_function' provides basic support for recursive
   894 function definitions over complete partial orders.  Concrete instances
   895 are provided for i) the option type, ii) tail recursion on arbitrary
   896 types, and iii) the heap monad of Imperative_HOL.  See
   897 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   898 for examples.
   899 
   900 * Function package: f.psimps rules are no longer implicitly declared
   901 as [simp].  INCOMPATIBILITY.
   902 
   903 * Datatype package: theorems generated for executable equality (class
   904 "eq") carry proper names and are treated as default code equations.
   905 
   906 * Inductive package: now offers command 'inductive_simps' to
   907 automatically derive instantiated and simplified equations for
   908 inductive predicates, similar to 'inductive_cases'.
   909 
   910 * Command 'enriched_type' allows to register properties of the
   911 functorial structure of types.
   912 
   913 * Improved infrastructure for term evaluation using code generator
   914 techniques, in particular static evaluation conversions.
   915 
   916 * Code generator: Scala (2.8 or higher) has been added to the target
   917 languages.
   918 
   919 * Code generator: globbing constant expressions "*" and "Theory.*"
   920 have been replaced by the more idiomatic "_" and "Theory._".
   921 INCOMPATIBILITY.
   922 
   923 * Code generator: export_code without explicit file declaration prints
   924 to standard output.  INCOMPATIBILITY.
   925 
   926 * Code generator: do not print function definitions for case
   927 combinators any longer.
   928 
   929 * Code generator: simplification with rules determined with
   930 src/Tools/Code/code_simp.ML and method "code_simp".
   931 
   932 * Code generator for records: more idiomatic representation of record
   933 types.  Warning: records are not covered by ancient SML code
   934 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   935 rep_datatype declaration helps to succeed then:
   936 
   937   record 'a foo = ...
   938   ...
   939   rep_datatype foo_ext ...
   940 
   941 * Records: logical foundation type for records does not carry a
   942 '_type' suffix any longer (obsolete due to authentic syntax).
   943 INCOMPATIBILITY.
   944 
   945 * Quickcheck now by default uses exhaustive testing instead of random
   946 testing.  Random testing can be invoked by "quickcheck [random]",
   947 exhaustive testing by "quickcheck [exhaustive]".
   948 
   949 * Quickcheck instantiates polymorphic types with small finite
   950 datatypes by default. This enables a simple execution mechanism to
   951 handle quantifiers and function equality over the finite datatypes.
   952 
   953 * Quickcheck random generator has been renamed from "code" to
   954 "random".  INCOMPATIBILITY.
   955 
   956 * Quickcheck now has a configurable time limit which is set to 30
   957 seconds by default. This can be changed by adding [timeout = n] to the
   958 quickcheck command. The time limit for Auto Quickcheck is still set
   959 independently.
   960 
   961 * Quickcheck in locales considers interpretations of that locale for
   962 counter example search.
   963 
   964 * Sledgehammer:
   965   - Added "smt" and "remote_smt" provers based on the "smt" proof
   966     method. See the Sledgehammer manual for details ("isabelle doc
   967     sledgehammer").
   968   - Renamed commands:
   969     sledgehammer atp_info ~> sledgehammer running_provers
   970     sledgehammer atp_kill ~> sledgehammer kill_provers
   971     sledgehammer available_atps ~> sledgehammer available_provers
   972     INCOMPATIBILITY.
   973   - Renamed options:
   974     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   975     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   976     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   977     (and "ms" and "min" are no longer supported)
   978     INCOMPATIBILITY.
   979 
   980 * Nitpick:
   981   - Renamed options:
   982     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   983     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   984     INCOMPATIBILITY.
   985   - Added support for partial quotient types.
   986   - Added local versions of the "Nitpick.register_xxx" functions.
   987   - Added "whack" option.
   988   - Allow registration of quotient types as codatatypes.
   989   - Improved "merge_type_vars" option to merge more types.
   990   - Removed unsound "fast_descrs" option.
   991   - Added custom symmetry breaking for datatypes, making it possible to reach
   992     higher cardinalities.
   993   - Prevent the expansion of too large definitions.
   994 
   995 * Proof methods "metis" and "meson" now have configuration options
   996 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   997 to diagnose these tools. E.g.
   998 
   999     using [[metis_trace = true]]
  1000 
  1001 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
  1002 manually as command 'solve_direct'.
  1003 
  1004 * The default SMT solver Z3 must be enabled explicitly (due to
  1005 licensing issues) by setting the environment variable
  1006 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
  1007 commercial applications, the SMT solver CVC3 is provided as fall-back;
  1008 changing the SMT solver is done via the configuration option
  1009 "smt_solver".
  1010 
  1011 * Remote SMT solvers need to be referred to by the "remote_" prefix,
  1012 i.e. "remote_cvc3" and "remote_z3".
  1013 
  1014 * Added basic SMT support for datatypes, records, and typedefs using
  1015 the oracle mode (no proofs).  Direct support of pairs has been dropped
  1016 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
  1017 support for a similar behavior).  Minor INCOMPATIBILITY.
  1018 
  1019 * Changed SMT configuration options:
  1020   - Renamed:
  1021     z3_proofs ~> smt_oracle (with inverted meaning)
  1022     z3_trace_assms ~> smt_trace_used_facts
  1023     INCOMPATIBILITY.
  1024   - Added:
  1025     smt_verbose
  1026     smt_random_seed
  1027     smt_datatypes
  1028     smt_infer_triggers
  1029     smt_monomorph_limit
  1030     cvc3_options
  1031     remote_cvc3_options
  1032     remote_z3_options
  1033     yices_options
  1034 
  1035 * Boogie output files (.b2i files) need to be declared in the theory
  1036 header.
  1037 
  1038 * Simplification procedure "list_to_set_comprehension" rewrites list
  1039 comprehensions applied to List.set to set comprehensions.  Occasional
  1040 INCOMPATIBILITY, may be deactivated like this:
  1041 
  1042   declare [[simproc del: list_to_set_comprehension]]
  1043 
  1044 * Removed old version of primrec package.  INCOMPATIBILITY.
  1045 
  1046 * Removed simplifier congruence rule of "prod_case", as has for long
  1047 been the case with "split".  INCOMPATIBILITY.
  1048 
  1049 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
  1050 
  1051 * Removed [split_format ... and ... and ...] version of
  1052 [split_format].  Potential INCOMPATIBILITY.
  1053 
  1054 * Predicate "sorted" now defined inductively, with nice induction
  1055 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
  1056 
  1057 * Constant "contents" renamed to "the_elem", to free the generic name
  1058 contents for other uses.  INCOMPATIBILITY.
  1059 
  1060 * Renamed class eq and constant eq (for code generation) to class
  1061 equal and constant equal, plus renaming of related facts and various
  1062 tuning.  INCOMPATIBILITY.
  1063 
  1064 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
  1065 
  1066 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
  1067 INCOMPATIBILITY.
  1068 
  1069 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
  1070 avoid confusion with finite sets.  INCOMPATIBILITY.
  1071 
  1072 * Abandoned locales equiv, congruent and congruent2 for equivalence
  1073 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
  1074 for congruent(2)).
  1075 
  1076 * Some previously unqualified names have been qualified:
  1077 
  1078   types
  1079     bool ~> HOL.bool
  1080     nat ~> Nat.nat
  1081 
  1082   constants
  1083     Trueprop ~> HOL.Trueprop
  1084     True ~> HOL.True
  1085     False ~> HOL.False
  1086     op & ~> HOL.conj
  1087     op | ~> HOL.disj
  1088     op --> ~> HOL.implies
  1089     op = ~> HOL.eq
  1090     Not ~> HOL.Not
  1091     The ~> HOL.The
  1092     All ~> HOL.All
  1093     Ex ~> HOL.Ex
  1094     Ex1 ~> HOL.Ex1
  1095     Let ~> HOL.Let
  1096     If ~> HOL.If
  1097     Ball ~> Set.Ball
  1098     Bex ~> Set.Bex
  1099     Suc ~> Nat.Suc
  1100     Pair ~> Product_Type.Pair
  1101     fst ~> Product_Type.fst
  1102     snd ~> Product_Type.snd
  1103     curry ~> Product_Type.curry
  1104     op : ~> Set.member
  1105     Collect ~> Set.Collect
  1106 
  1107 INCOMPATIBILITY.
  1108 
  1109 * More canonical naming convention for some fundamental definitions:
  1110 
  1111     bot_bool_eq ~> bot_bool_def
  1112     top_bool_eq ~> top_bool_def
  1113     inf_bool_eq ~> inf_bool_def
  1114     sup_bool_eq ~> sup_bool_def
  1115     bot_fun_eq  ~> bot_fun_def
  1116     top_fun_eq  ~> top_fun_def
  1117     inf_fun_eq  ~> inf_fun_def
  1118     sup_fun_eq  ~> sup_fun_def
  1119 
  1120 INCOMPATIBILITY.
  1121 
  1122 * More stylized fact names:
  1123 
  1124   expand_fun_eq ~> fun_eq_iff
  1125   expand_set_eq ~> set_eq_iff
  1126   set_ext       ~> set_eqI
  1127   nat_number    ~> eval_nat_numeral
  1128 
  1129 INCOMPATIBILITY.
  1130 
  1131 * Refactoring of code-generation specific operations in theory List:
  1132 
  1133   constants
  1134     null ~> List.null
  1135 
  1136   facts
  1137     mem_iff ~> member_def
  1138     null_empty ~> null_def
  1139 
  1140 INCOMPATIBILITY.  Note that these were not supposed to be used
  1141 regularly unless for striking reasons; their main purpose was code
  1142 generation.
  1143 
  1144 Various operations from the Haskell prelude are used for generating
  1145 Haskell code.
  1146 
  1147 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
  1148 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
  1149 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
  1150 
  1151 * Abolished some non-alphabetic type names: "prod" and "sum" replace
  1152 "*" and "+" respectively.  INCOMPATIBILITY.
  1153 
  1154 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
  1155 "Sum_Type.Plus" instead.
  1156 
  1157 * Constant "split" has been merged with constant "prod_case"; names of
  1158 ML functions, facts etc. involving split have been retained so far,
  1159 though.  INCOMPATIBILITY.
  1160 
  1161 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
  1162 instead.  INCOMPATIBILITY.
  1163 
  1164 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
  1165 INCOMPATIBILITY.
  1166 
  1167 * Former theory Library/Enum is now part of the HOL-Main image.
  1168 INCOMPATIBILITY: all constants of the Enum theory now have to be
  1169 referred to by its qualified name.
  1170 
  1171   enum    ~>  Enum.enum
  1172   nlists  ~>  Enum.nlists
  1173   product ~>  Enum.product
  1174 
  1175 * Theory Library/Monad_Syntax provides do-syntax for monad types.
  1176 Syntax in Library/State_Monad has been changed to avoid ambiguities.
  1177 INCOMPATIBILITY.
  1178 
  1179 * Theory Library/SetsAndFunctions has been split into
  1180 Library/Function_Algebras and Library/Set_Algebras; canonical names
  1181 for instance definitions for functions; various improvements.
  1182 INCOMPATIBILITY.
  1183 
  1184 * Theory Library/Multiset provides stable quicksort implementation of
  1185 sort_key.
  1186 
  1187 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
  1188 INCOMPATIBILITY.
  1189 
  1190 * Session Multivariate_Analysis: introduced a type class for euclidean
  1191 space.  Most theorems are now stated in terms of euclidean spaces
  1192 instead of finite cartesian products.
  1193 
  1194   types
  1195     real ^ 'n ~>  'a::real_vector
  1196               ~>  'a::euclidean_space
  1197               ~>  'a::ordered_euclidean_space
  1198         (depends on your needs)
  1199 
  1200   constants
  1201      _ $ _        ~> _ $$ _
  1202      \<chi> x. _  ~> \<chi>\<chi> x. _
  1203      CARD('n)     ~> DIM('a)
  1204 
  1205 Also note that the indices are now natural numbers and not from some
  1206 finite type. Finite cartesian products of euclidean spaces, products
  1207 of euclidean spaces the real and complex numbers are instantiated to
  1208 be euclidean_spaces.  INCOMPATIBILITY.
  1209 
  1210 * Session Probability: introduced pextreal as positive extended real
  1211 numbers.  Use pextreal as value for measures.  Introduce the
  1212 Radon-Nikodym derivative, product spaces and Fubini's theorem for
  1213 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
  1214 the integral in Multivariate Analysis.  INCOMPATIBILITY.
  1215 
  1216 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
  1217 INCOMPATIBILITY.
  1218 
  1219 * Session SPARK (with image HOL-SPARK) provides commands to load and
  1220 prove verification conditions generated by the SPARK Ada program
  1221 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
  1222 
  1223 
  1224 *** HOL-Algebra ***
  1225 
  1226 * Theorems for additive ring operations (locale abelian_monoid and
  1227 descendants) are generated by interpretation from their multiplicative
  1228 counterparts.  Names (in particular theorem names) have the mandatory
  1229 qualifier 'add'.  Previous theorem names are redeclared for
  1230 compatibility.
  1231 
  1232 * Structure "int_ring" is now an abbreviation (previously a
  1233 definition).  This fits more natural with advanced interpretations.
  1234 
  1235 
  1236 *** HOLCF ***
  1237 
  1238 * The domain package now runs in definitional mode by default: The
  1239 former command 'new_domain' is now called 'domain'.  To use the domain
  1240 package in its original axiomatic mode, use 'domain (unsafe)'.
  1241 INCOMPATIBILITY.
  1242 
  1243 * The new class "domain" is now the default sort.  Class "predomain"
  1244 is an unpointed version of "domain". Theories can be updated by
  1245 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1246 
  1247   'a::type ~> 'a::countable
  1248   'a::cpo  ~> 'a::predomain
  1249   'a::pcpo ~> 'a::domain
  1250 
  1251 * The old type class "rep" has been superseded by class "domain".
  1252 Accordingly, users of the definitional package must remove any
  1253 "default_sort rep" declarations.  INCOMPATIBILITY.
  1254 
  1255 * The domain package (definitional mode) now supports unpointed
  1256 predomain argument types, as long as they are marked 'lazy'. (Strict
  1257 arguments must be in class "domain".) For example, the following
  1258 domain definition now works:
  1259 
  1260   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1261 
  1262 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1263 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1264 'a option, and 'a list.  Additionally, it configures fixrec and the
  1265 domain package to work with these types.  For example:
  1266 
  1267   fixrec isInl :: "('a + 'b) u -> tr"
  1268     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1269 
  1270   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1271 
  1272 * The "(permissive)" option of fixrec has been replaced with a
  1273 per-equation "(unchecked)" option. See
  1274 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1275 
  1276 * The "bifinite" class no longer fixes a constant "approx"; the class
  1277 now just asserts that such a function exists.  INCOMPATIBILITY.
  1278 
  1279 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1280 defines an embedding of type 'a defl into udom by default; instances
  1281 of "bifinite" and "domain" classes are available in
  1282 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1283 
  1284 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1285 
  1286 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1287 
  1288 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1289 
  1290 * The function "cprod_map" has been renamed to "prod_map".
  1291 INCOMPATIBILITY.
  1292 
  1293 * The monadic bind operator on each powerdomain has new binder syntax
  1294 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1295 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1296 
  1297 * The infix syntax for binary union on each powerdomain has changed
  1298 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1299 syntax.  INCOMPATIBILITY.
  1300 
  1301 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1302 still supported as an input translation.
  1303 
  1304 * Renamed some theorems (the original names are also still available).
  1305 
  1306   expand_fun_below   ~> fun_below_iff
  1307   below_fun_ext      ~> fun_belowI
  1308   expand_cfun_eq     ~> cfun_eq_iff
  1309   ext_cfun           ~> cfun_eqI
  1310   expand_cfun_below  ~> cfun_below_iff
  1311   below_cfun_ext     ~> cfun_belowI
  1312   cont2cont_Rep_CFun ~> cont2cont_APP
  1313 
  1314 * The Abs and Rep functions for various types have changed names.
  1315 Related theorem names have also changed to match. INCOMPATIBILITY.
  1316 
  1317   Rep_CFun  ~> Rep_cfun
  1318   Abs_CFun  ~> Abs_cfun
  1319   Rep_Sprod ~> Rep_sprod
  1320   Abs_Sprod ~> Abs_sprod
  1321   Rep_Ssum  ~> Rep_ssum
  1322   Abs_Ssum  ~> Abs_ssum
  1323 
  1324 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1325 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1326 
  1327 * Various changes to bisimulation/coinduction with domain package:
  1328 
  1329   - Definitions of "bisim" constants no longer mention definedness.
  1330   - With mutual recursion, "bisim" predicate is now curried.
  1331   - With mutual recursion, each type gets a separate coind theorem.
  1332   - Variable names in bisim_def and coinduct rules have changed.
  1333 
  1334 INCOMPATIBILITY.
  1335 
  1336 * Case combinators generated by the domain package for type "foo" are
  1337 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1338 
  1339 * Several theorems have been renamed to more accurately reflect the
  1340 names of constants and types involved.  INCOMPATIBILITY.
  1341 
  1342   thelub_const    ~> lub_const
  1343   lub_const       ~> is_lub_const
  1344   thelubI         ~> lub_eqI
  1345   is_lub_lub      ~> is_lubD2
  1346   lubI            ~> is_lub_lub
  1347   unique_lub      ~> is_lub_unique
  1348   is_ub_lub       ~> is_lub_rangeD1
  1349   lub_bin_chain   ~> is_lub_bin_chain
  1350   lub_fun         ~> is_lub_fun
  1351   thelub_fun      ~> lub_fun
  1352   thelub_cfun     ~> lub_cfun
  1353   thelub_Pair     ~> lub_Pair
  1354   lub_cprod       ~> is_lub_prod
  1355   thelub_cprod    ~> lub_prod
  1356   minimal_cprod   ~> minimal_prod
  1357   inst_cprod_pcpo ~> inst_prod_pcpo
  1358   UU_I            ~> bottomI
  1359   compact_UU      ~> compact_bottom
  1360   deflation_UU    ~> deflation_bottom
  1361   finite_deflation_UU ~> finite_deflation_bottom
  1362 
  1363 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1364 
  1365   sq_ord_less_eq_trans ~> below_eq_trans
  1366   sq_ord_eq_less_trans ~> eq_below_trans
  1367   refl_less            ~> below_refl
  1368   trans_less           ~> below_trans
  1369   antisym_less         ~> below_antisym
  1370   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1371   box_less             ~> box_below
  1372   rev_trans_less       ~> rev_below_trans
  1373   not_less2not_eq      ~> not_below2not_eq
  1374   less_UU_iff          ~> below_UU_iff
  1375   flat_less_iff        ~> flat_below_iff
  1376   adm_less             ~> adm_below
  1377   adm_not_less         ~> adm_not_below
  1378   adm_compact_not_less ~> adm_compact_not_below
  1379   less_fun_def         ~> below_fun_def
  1380   expand_fun_less      ~> fun_below_iff
  1381   less_fun_ext         ~> fun_belowI
  1382   less_discr_def       ~> below_discr_def
  1383   discr_less_eq        ~> discr_below_eq
  1384   less_unit_def        ~> below_unit_def
  1385   less_cprod_def       ~> below_prod_def
  1386   prod_lessI           ~> prod_belowI
  1387   Pair_less_iff        ~> Pair_below_iff
  1388   fst_less_iff         ~> fst_below_iff
  1389   snd_less_iff         ~> snd_below_iff
  1390   expand_cfun_less     ~> cfun_below_iff
  1391   less_cfun_ext        ~> cfun_belowI
  1392   injection_less       ~> injection_below
  1393   less_up_def          ~> below_up_def
  1394   not_Iup_less         ~> not_Iup_below
  1395   Iup_less             ~> Iup_below
  1396   up_less              ~> up_below
  1397   Def_inject_less_eq   ~> Def_below_Def
  1398   Def_less_is_eq       ~> Def_below_iff
  1399   spair_less_iff       ~> spair_below_iff
  1400   less_sprod           ~> below_sprod
  1401   spair_less           ~> spair_below
  1402   sfst_less_iff        ~> sfst_below_iff
  1403   ssnd_less_iff        ~> ssnd_below_iff
  1404   fix_least_less       ~> fix_least_below
  1405   dist_less_one        ~> dist_below_one
  1406   less_ONE             ~> below_ONE
  1407   ONE_less_iff         ~> ONE_below_iff
  1408   less_sinlD           ~> below_sinlD
  1409   less_sinrD           ~> below_sinrD
  1410 
  1411 
  1412 *** FOL and ZF ***
  1413 
  1414 * All constant names are now qualified internally and use proper
  1415 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1416 
  1417 
  1418 *** ML ***
  1419 
  1420 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1421 Fail if the argument is false.  Due to inlining the source position of
  1422 failed assertions is included in the error output.
  1423 
  1424 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1425 text is in practice always evaluated with a stable theory checkpoint.
  1426 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1427 
  1428 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1429 the current context, not any accidental theory loader state as before.
  1430 Potential INCOMPATIBILITY, subtle change in semantics.
  1431 
  1432 * Syntax.pretty_priority (default 0) configures the required priority
  1433 of pretty-printed output and thus affects insertion of parentheses.
  1434 
  1435 * Syntax.default_root (default "any") configures the inner syntax
  1436 category (nonterminal symbol) for parsing of terms.
  1437 
  1438 * Former exception Library.UnequalLengths now coincides with
  1439 ListPair.UnequalLengths.
  1440 
  1441 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1442 main functionality is provided by structure Simplifier.
  1443 
  1444 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1445 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1446 almost all situations.
  1447 
  1448 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1449 See implementation manual for further details on exceptions in
  1450 Isabelle/ML.
  1451 
  1452 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1453 meaning.
  1454 
  1455 * Renamed structure PureThy to Pure_Thy and moved most of its
  1456 operations to structure Global_Theory, to emphasize that this is
  1457 rarely-used global-only stuff.
  1458 
  1459 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1460 instead (or tracing for high-volume output).
  1461 
  1462 * Configuration option show_question_marks only affects regular pretty
  1463 printing of types and terms, not raw Term.string_of_vname.
  1464 
  1465 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1466 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1467 @{thms} for most purposes.
  1468 
  1469 * ML structure Unsynchronized is never opened, not even in Isar
  1470 interaction mode as before.  Old Unsynchronized.set etc. have been
  1471 discontinued -- use plain := instead.  This should be *rare* anyway,
  1472 since modern tools always work via official context data, notably
  1473 configuration options.
  1474 
  1475 * Parallel and asynchronous execution requires special care concerning
  1476 interrupts.  Structure Exn provides some convenience functions that
  1477 avoid working directly with raw Interrupt.  User code must not absorb
  1478 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1479 followed by re-raising of the original exception.  Another common
  1480 source of mistakes are "handle _" patterns, which make the meaning of
  1481 the program subject to physical effects of the environment.
  1482 
  1483 
  1484 
  1485 New in Isabelle2009-2 (June 2010)
  1486 ---------------------------------
  1487 
  1488 *** General ***
  1489 
  1490 * Authentic syntax for *all* logical entities (type classes, type
  1491 constructors, term constants): provides simple and robust
  1492 correspondence between formal entities and concrete syntax.  Within
  1493 the parse tree / AST representations, "constants" are decorated by
  1494 their category (class, type, const) and spelled out explicitly with
  1495 their full internal name.
  1496 
  1497 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1498 and translations (translation rules and translation functions in ML).
  1499 Some hints on upgrading:
  1500 
  1501   - Many existing uses of 'syntax' and 'translations' can be replaced
  1502     by more modern 'type_notation', 'notation' and 'abbreviation',
  1503     which are independent of this issue.
  1504 
  1505   - 'translations' require markup within the AST; the term syntax
  1506     provides the following special forms:
  1507 
  1508       CONST c   -- produces syntax version of constant c from context
  1509       XCONST c  -- literally c, checked as constant from context
  1510       c         -- literally c, if declared by 'syntax'
  1511 
  1512     Plain identifiers are treated as AST variables -- occasionally the
  1513     system indicates accidental variables via the error "rhs contains
  1514     extra variables".
  1515 
  1516     Type classes and type constructors are marked according to their
  1517     concrete syntax.  Some old translations rules need to be written
  1518     for the "type" category, using type constructor application
  1519     instead of pseudo-term application of the default category
  1520     "logic".
  1521 
  1522   - 'parse_translation' etc. in ML may use the following
  1523     antiquotations:
  1524 
  1525       @{class_syntax c}   -- type class c within parse tree / AST
  1526       @{term_syntax c}    -- type constructor c within parse tree / AST
  1527       @{const_syntax c}   -- ML version of "CONST c" above
  1528       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1529 
  1530   - Literal types within 'typed_print_translations', i.e. those *not*
  1531     represented as pseudo-terms are represented verbatim.  Use @{class
  1532     c} or @{type_name c} here instead of the above syntax
  1533     antiquotations.
  1534 
  1535 Note that old non-authentic syntax was based on unqualified base
  1536 names, so all of the above "constant" names would coincide.  Recall
  1537 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1538 diagnose syntax problems.
  1539 
  1540 * Type constructors admit general mixfix syntax, not just infix.
  1541 
  1542 * Concrete syntax may be attached to local entities without a proof
  1543 body, too.  This works via regular mixfix annotations for 'fix',
  1544 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1545 similar to the 'notation' command in theory specifications.
  1546 
  1547 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1548 need to specify constant name and syntax separately.  Internal ML
  1549 datatype constructors have been renamed from InfixName to Infix etc.
  1550 Minor INCOMPATIBILITY.
  1551 
  1552 * Schematic theorem statements need to be explicitly markup as such,
  1553 via commands 'schematic_lemma', 'schematic_theorem',
  1554 'schematic_corollary'.  Thus the relevance of the proof is made
  1555 syntactically clear, which impacts performance in a parallel or
  1556 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1557 
  1558 * Use of cumulative prems via "!" in some proof methods has been
  1559 discontinued (old legacy feature).
  1560 
  1561 * References 'trace_simp' and 'debug_simp' have been replaced by
  1562 configuration options stored in the context. Enabling tracing (the
  1563 case of debugging is similar) in proofs works via
  1564 
  1565   using [[trace_simp = true]]
  1566 
  1567 Tracing is then active for all invocations of the simplifier in
  1568 subsequent goal refinement steps. Tracing may also still be enabled or
  1569 disabled via the ProofGeneral settings menu.
  1570 
  1571 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1572 'hide_fact' replace the former 'hide' KIND command.  Minor
  1573 INCOMPATIBILITY.
  1574 
  1575 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1576 more efficient than combinations with -q1 or -q2.
  1577 
  1578 
  1579 *** Pure ***
  1580 
  1581 * Proofterms record type-class reasoning explicitly, using the
  1582 "unconstrain" operation internally.  This eliminates all sort
  1583 constraints from a theorem and proof, introducing explicit
  1584 OFCLASS-premises.  On the proof term level, this operation is
  1585 automatically applied at theorem boundaries, such that closed proofs
  1586 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1587 inspect proof terms.
  1588 
  1589 * Local theory specifications may depend on extra type variables that
  1590 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1591 are added internally.  For example:
  1592 
  1593   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1594 
  1595 * Predicates of locales introduced by classes carry a mandatory
  1596 "class" prefix.  INCOMPATIBILITY.
  1597 
  1598 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1599 
  1600 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1601 'class' instead.
  1602 
  1603 * Command 'code_reflect' allows to incorporate generated ML code into
  1604 runtime environment; replaces immature code_datatype antiquotation.
  1605 INCOMPATIBILITY.
  1606 
  1607 * Code generator: simple concept for abstract datatypes obeying
  1608 invariants.
  1609 
  1610 * Code generator: details of internal data cache have no impact on the
  1611 user space functionality any longer.
  1612 
  1613 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1614 subgoals.  This is more appropriate for interpretations with 'where'.
  1615 INCOMPATIBILITY.
  1616 
  1617 * Command 'example_proof' opens an empty proof body.  This allows to
  1618 experiment with Isar, without producing any persistent result.
  1619 
  1620 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1621 within a local theory context, with explicit checking of the
  1622 constructors involved (in contrast to the raw 'syntax' versions).
  1623 
  1624 * Commands 'types' and 'typedecl' now work within a local theory
  1625 context -- without introducing dependencies on parameters or
  1626 assumptions, which is not possible in Isabelle/Pure.
  1627 
  1628 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1629 within a local theory context.  Minor INCOMPATIBILITY.
  1630 
  1631 
  1632 *** HOL ***
  1633 
  1634 * Command 'typedef' now works within a local theory context -- without
  1635 introducing dependencies on parameters or assumptions, which is not
  1636 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1637 contain multiple interpretations of local typedefs (with different
  1638 non-emptiness proofs), even in a global theory context.
  1639 
  1640 * New package for quotient types.  Commands 'quotient_type' and
  1641 'quotient_definition' may be used for defining types and constants by
  1642 quotient constructions.  An example is the type of integers created by
  1643 quotienting pairs of natural numbers:
  1644 
  1645   fun
  1646     intrel :: "(nat * nat) => (nat * nat) => bool"
  1647   where
  1648     "intrel (x, y) (u, v) = (x + v = u + y)"
  1649 
  1650   quotient_type int = "nat * nat" / intrel
  1651     by (auto simp add: equivp_def expand_fun_eq)
  1652 
  1653   quotient_definition
  1654     "0::int" is "(0::nat, 0::nat)"
  1655 
  1656 The method "lifting" can be used to lift of theorems from the
  1657 underlying "raw" type to the quotient type.  The example
  1658 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1659 construction and provides a reasoning infrastructure for finite sets.
  1660 
  1661 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1662 clash with new theory Quotient in Main HOL.
  1663 
  1664 * Moved the SMT binding into the main HOL session, eliminating
  1665 separate HOL-SMT session.
  1666 
  1667 * List membership infix mem operation is only an input abbreviation.
  1668 INCOMPATIBILITY.
  1669 
  1670 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1671 for future developements; former Library/Word.thy is still present in
  1672 the AFP entry RSAPPS.
  1673 
  1674 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1675 longer shadowed.  INCOMPATIBILITY.
  1676 
  1677 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1678 INCOMPATIBILITY.
  1679 
  1680 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1681 INCOMPATIBILITY.
  1682 
  1683 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1684 instead.  INCOMPATIBILITY.
  1685 
  1686 * Dropped several real-specific versions of lemmas about floor and
  1687 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1688 instead.  INCOMPATIBILITY.
  1689 
  1690   floor_number_of_eq         ~> floor_number_of
  1691   le_floor_eq_number_of      ~> number_of_le_floor
  1692   le_floor_eq_zero           ~> zero_le_floor
  1693   le_floor_eq_one            ~> one_le_floor
  1694   floor_less_eq_number_of    ~> floor_less_number_of
  1695   floor_less_eq_zero         ~> floor_less_zero
  1696   floor_less_eq_one          ~> floor_less_one
  1697   less_floor_eq_number_of    ~> number_of_less_floor
  1698   less_floor_eq_zero         ~> zero_less_floor
  1699   less_floor_eq_one          ~> one_less_floor
  1700   floor_le_eq_number_of      ~> floor_le_number_of
  1701   floor_le_eq_zero           ~> floor_le_zero
  1702   floor_le_eq_one            ~> floor_le_one
  1703   floor_subtract_number_of   ~> floor_diff_number_of
  1704   floor_subtract_one         ~> floor_diff_one
  1705   ceiling_number_of_eq       ~> ceiling_number_of
  1706   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1707   ceiling_le_zero_eq         ~> ceiling_le_zero
  1708   ceiling_le_eq_one          ~> ceiling_le_one
  1709   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1710   less_ceiling_eq_zero       ~> zero_less_ceiling
  1711   less_ceiling_eq_one        ~> one_less_ceiling
  1712   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1713   ceiling_less_eq_zero       ~> ceiling_less_zero
  1714   ceiling_less_eq_one        ~> ceiling_less_one
  1715   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1716   le_ceiling_eq_zero         ~> zero_le_ceiling
  1717   le_ceiling_eq_one          ~> one_le_ceiling
  1718   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1719   ceiling_subtract_one       ~> ceiling_diff_one
  1720 
  1721 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1722 application of the various fold combinators on finite sets.
  1723 
  1724 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1725 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1726 implementation.  INCOMPATIBILTY.
  1727 
  1728 * Theory Library/Coinductive_List has been removed -- superseded by
  1729 AFP/thys/Coinductive.
  1730 
  1731 * Theory PReal, including the type "preal" and related operations, has
  1732 been removed.  INCOMPATIBILITY.
  1733 
  1734 * Real: new development using Cauchy Sequences.
  1735 
  1736 * Split off theory "Big_Operators" containing setsum, setprod,
  1737 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1738 
  1739 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1740 "Int" etc.  INCOMPATIBILITY.
  1741 
  1742 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1743 
  1744 * New set of rules "ac_simps" provides combined assoc / commute
  1745 rewrites for all interpretations of the appropriate generic locales.
  1746 
  1747 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1748 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1749 appropriate and more consistent names suitable for name prefixes
  1750 within the HOL theories.  INCOMPATIBILITY.
  1751 
  1752 * Some generic constants have been put to appropriate theories:
  1753   - less_eq, less: Orderings
  1754   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1755   - inverse, divide: Rings
  1756 INCOMPATIBILITY.
  1757 
  1758 * More consistent naming of type classes involving orderings (and
  1759 lattices):
  1760 
  1761     lower_semilattice                   ~> semilattice_inf
  1762     upper_semilattice                   ~> semilattice_sup
  1763 
  1764     dense_linear_order                  ~> dense_linorder
  1765 
  1766     pordered_ab_group_add               ~> ordered_ab_group_add
  1767     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1768     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1769     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1770     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1771     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1772     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1773     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1774     pordered_comm_ring                  ~> ordered_comm_ring
  1775     pordered_comm_semiring              ~> ordered_comm_semiring
  1776     pordered_ring                       ~> ordered_ring
  1777     pordered_ring_abs                   ~> ordered_ring_abs
  1778     pordered_semiring                   ~> ordered_semiring
  1779 
  1780     ordered_ab_group_add                ~> linordered_ab_group_add
  1781     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1782     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1783     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1784     ordered_field                       ~> linordered_field
  1785     ordered_field_no_lb                 ~> linordered_field_no_lb
  1786     ordered_field_no_ub                 ~> linordered_field_no_ub
  1787     ordered_field_dense_linear_order    ~> dense_linordered_field
  1788     ordered_idom                        ~> linordered_idom
  1789     ordered_ring                        ~> linordered_ring
  1790     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1791     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1792     ordered_ring_strict                 ~> linordered_ring_strict
  1793     ordered_semidom                     ~> linordered_semidom
  1794     ordered_semiring                    ~> linordered_semiring
  1795     ordered_semiring_1                  ~> linordered_semiring_1
  1796     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1797     ordered_semiring_strict             ~> linordered_semiring_strict
  1798 
  1799   The following slightly odd type classes have been moved to a
  1800   separate theory Library/Lattice_Algebras:
  1801 
  1802     lordered_ab_group_add               ~> lattice_ab_group_add
  1803     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1804     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1805     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1806     lordered_ring                       ~> lattice_ring
  1807 
  1808 INCOMPATIBILITY.
  1809 
  1810 * Refined field classes:
  1811   - classes division_ring_inverse_zero, field_inverse_zero,
  1812     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1813     subsumes former division_by_zero class;
  1814   - numerous lemmas have been ported from field to division_ring.
  1815 INCOMPATIBILITY.
  1816 
  1817 * Refined algebra theorem collections:
  1818   - dropped theorem group group_simps, use algebra_simps instead;
  1819   - dropped theorem group ring_simps, use field_simps instead;
  1820   - proper theorem collection field_simps subsumes former theorem
  1821     groups field_eq_simps and field_simps;
  1822   - dropped lemma eq_minus_self_iff which is a duplicate for
  1823     equal_neg_zero.
  1824 INCOMPATIBILITY.
  1825 
  1826 * Theory Finite_Set and List: some lemmas have been generalized from
  1827 sets to lattices:
  1828 
  1829   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1830   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1831   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1832   union_Union_fold_union        ~> sup_Sup_fold_sup
  1833   Inter_fold_inter              ~> Inf_fold_inf
  1834   Union_fold_union              ~> Sup_fold_sup
  1835   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1836   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1837   INTER_fold_inter              ~> INFI_fold_inf
  1838   UNION_fold_union              ~> SUPR_fold_sup
  1839 
  1840 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1841 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1842 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1843 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1844 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1845 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1846 
  1847 * Reorganized theory Multiset: swapped notation of pointwise and
  1848 multiset order:
  1849 
  1850   - pointwise ordering is instance of class order with standard syntax
  1851     <= and <;
  1852   - multiset ordering has syntax <=# and <#; partial order properties
  1853     are provided by means of interpretation with prefix
  1854     multiset_order;
  1855   - less duplication, less historical organization of sections,
  1856     conversion from associations lists to multisets, rudimentary code
  1857     generation;
  1858   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1859     if needed.
  1860 
  1861 Renamed:
  1862 
  1863   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1864   multi_count_ext  ~>  multiset_ext
  1865   diff_union_inverse2  ~>  diff_union_cancelR
  1866 
  1867 INCOMPATIBILITY.
  1868 
  1869 * Theory Permutation: replaced local "remove" by List.remove1.
  1870 
  1871 * Code generation: ML and OCaml code is decorated with signatures.
  1872 
  1873 * Theory List: added transpose.
  1874 
  1875 * Library/Nat_Bijection.thy is a collection of bijective functions
  1876 between nat and other types, which supersedes the older libraries
  1877 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1878 
  1879   Constants:
  1880   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1881   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1882   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1883   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1884   Countable.pair_encode           ~> prod_encode
  1885   NatIso.prod2nat                 ~> prod_encode
  1886   NatIso.nat2prod                 ~> prod_decode
  1887   NatIso.sum2nat                  ~> sum_encode
  1888   NatIso.nat2sum                  ~> sum_decode
  1889   NatIso.list2nat                 ~> list_encode
  1890   NatIso.nat2list                 ~> list_decode
  1891   NatIso.set2nat                  ~> set_encode
  1892   NatIso.nat2set                  ~> set_decode
  1893 
  1894   Lemmas:
  1895   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1896   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1897   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1898   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1899   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1900   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1901   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1902   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1903   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1904   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1905   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1906   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1907   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1908 
  1909 * Sledgehammer:
  1910   - Renamed ATP commands:
  1911     atp_info     ~> sledgehammer running_atps
  1912     atp_kill     ~> sledgehammer kill_atps
  1913     atp_messages ~> sledgehammer messages
  1914     atp_minimize ~> sledgehammer minimize
  1915     print_atps   ~> sledgehammer available_atps
  1916     INCOMPATIBILITY.
  1917   - Added user's manual ("isabelle doc sledgehammer").
  1918   - Added option syntax and "sledgehammer_params" to customize
  1919     Sledgehammer's behavior.  See the manual for details.
  1920   - Modified the Isar proof reconstruction code so that it produces
  1921     direct proofs rather than proofs by contradiction.  (This feature
  1922     is still experimental.)
  1923   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1924     full-typed mode.
  1925   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1926 
  1927 * Nitpick:
  1928   - Added and implemented "binary_ints" and "bits" options.
  1929   - Added "std" option and implemented support for nonstandard models.
  1930   - Added and implemented "finitize" option to improve the precision
  1931     of infinite datatypes based on a monotonicity analysis.
  1932   - Added support for quotient types.
  1933   - Added support for "specification" and "ax_specification"
  1934     constructs.
  1935   - Added support for local definitions (for "function" and
  1936     "termination" proofs).
  1937   - Added support for term postprocessors.
  1938   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1939   - Improved efficiency of "destroy_constrs" optimization.
  1940   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1941     record getters.
  1942   - Fixed soundness bug related to higher-order constructors.
  1943   - Fixed soundness bug when "full_descrs" is enabled.
  1944   - Improved precision of set constructs.
  1945   - Added "atoms" option.
  1946   - Added cache to speed up repeated Kodkod invocations on the same
  1947     problems.
  1948   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1949     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1950     "SAT4J_Light".  INCOMPATIBILITY.
  1951   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1952     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1953   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1954 
  1955 * Method "induct" now takes instantiations of the form t, where t is not
  1956   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1957   If this is not intended, t has to be enclosed in parentheses.
  1958   By default, the equalities generated by definitional instantiations
  1959   are pre-simplified, which may cause parameters of inductive cases
  1960   to disappear, or may even delete some of the inductive cases.
  1961   Use "induct (no_simp)" instead of "induct" to restore the old
  1962   behaviour. The (no_simp) option is also understood by the "cases"
  1963   and "nominal_induct" methods, which now perform pre-simplification, too.
  1964   INCOMPATIBILITY.
  1965 
  1966 
  1967 *** HOLCF ***
  1968 
  1969 * Variable names in lemmas generated by the domain package have
  1970 changed; the naming scheme is now consistent with the HOL datatype
  1971 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1972 
  1973 * The domain package no longer defines the function "foo_copy" for
  1974 recursive domain "foo".  The reach lemma is now stated directly in
  1975 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1976 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1977 
  1978 * Most definedness lemmas generated by the domain package (previously
  1979 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1980 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1981 Proofs that used definedness lemmas as intro rules may break,
  1982 potential INCOMPATIBILITY.
  1983 
  1984 * Induction and casedist rules generated by the domain package now
  1985 declare proper case_names (one called "bottom", and one named for each
  1986 constructor).  INCOMPATIBILITY.
  1987 
  1988 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1989 rules are generated for each domain, INCOMPATIBILITY.
  1990 
  1991   foo_bar.reach       ~> foo.reach  bar.reach
  1992   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1993 
  1994 * Some lemmas generated by the domain package have been renamed for
  1995 consistency with the datatype package, INCOMPATIBILITY.
  1996 
  1997   foo.ind        ~> foo.induct
  1998   foo.finite_ind ~> foo.finite_induct
  1999   foo.coind      ~> foo.coinduct
  2000   foo.casedist   ~> foo.exhaust
  2001   foo.exhaust    ~> foo.nchotomy
  2002 
  2003 * For consistency with other definition packages, the fixrec package
  2004 now generates qualified theorem names, INCOMPATIBILITY.
  2005 
  2006   foo_simps  ~> foo.simps
  2007   foo_unfold ~> foo.unfold
  2008   foo_induct ~> foo.induct
  2009 
  2010 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  2011 method and internal fixrec proofs now use the default simpset instead.
  2012 INCOMPATIBILITY.
  2013 
  2014 * The "contlub" predicate has been removed.  Proof scripts should use
  2015 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  2016 
  2017 * The "admw" predicate has been removed, INCOMPATIBILITY.
  2018 
  2019 * The constants cpair, cfst, and csnd have been removed in favor of
  2020 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  2021 
  2022 
  2023 *** ML ***
  2024 
  2025 * Antiquotations for basic formal entities:
  2026 
  2027     @{class NAME}         -- type class
  2028     @{class_syntax NAME}  -- syntax representation of the above
  2029 
  2030     @{type_name NAME}     -- logical type
  2031     @{type_abbrev NAME}   -- type abbreviation
  2032     @{nonterminal NAME}   -- type of concrete syntactic category
  2033     @{type_syntax NAME}   -- syntax representation of any of the above
  2034 
  2035     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  2036     @{const_abbrev NAME}  -- abbreviated constant
  2037     @{const_syntax NAME}  -- syntax representation of any of the above
  2038 
  2039 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  2040 syntax constant (cf. 'syntax' command).
  2041 
  2042 * Antiquotation @{make_string} inlines a function to print arbitrary
  2043 values similar to the ML toplevel.  The result is compiler dependent
  2044 and may fall back on "?" in certain situations.
  2045 
  2046 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  2047 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  2048 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  2049 not work with the asynchronous Isar document model.
  2050 
  2051 * Configuration options now admit dynamic default values, depending on
  2052 the context or even global references.
  2053 
  2054 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  2055 uses an efficient external library if available (for Poly/ML).
  2056 
  2057 * Renamed some important ML structures, while keeping the old names
  2058 for some time as aliases within the structure Legacy:
  2059 
  2060   OuterKeyword  ~>  Keyword
  2061   OuterLex      ~>  Token
  2062   OuterParse    ~>  Parse
  2063   OuterSyntax   ~>  Outer_Syntax
  2064   PrintMode     ~>  Print_Mode
  2065   SpecParse     ~>  Parse_Spec
  2066   ThyInfo       ~>  Thy_Info
  2067   ThyLoad       ~>  Thy_Load
  2068   ThyOutput     ~>  Thy_Output
  2069   TypeInfer     ~>  Type_Infer
  2070 
  2071 Note that "open Legacy" simplifies porting of sources, but forgetting
  2072 to remove it again will complicate porting again in the future.
  2073 
  2074 * Most operations that refer to a global context are named
  2075 accordingly, e.g. Simplifier.global_context or
  2076 ProofContext.init_global.  There are some situations where a global
  2077 context actually works, but under normal circumstances one needs to
  2078 pass the proper local context through the code!
  2079 
  2080 * Discontinued old TheoryDataFun with its copy/init operation -- data
  2081 needs to be pure.  Functor Theory_Data_PP retains the traditional
  2082 Pretty.pp argument to merge, which is absent in the standard
  2083 Theory_Data version.
  2084 
  2085 * Sorts.certify_sort and derived "cert" operations for types and terms
  2086 no longer minimize sorts.  Thus certification at the boundary of the
  2087 inference kernel becomes invariant under addition of class relations,
  2088 which is an important monotonicity principle.  Sorts are now minimized
  2089 in the syntax layer only, at the boundary between the end-user and the
  2090 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  2091 explicitly in rare situations.
  2092 
  2093 * Renamed old-style Drule.standard to Drule.export_without_context, to
  2094 emphasize that this is in no way a standard operation.
  2095 INCOMPATIBILITY.
  2096 
  2097 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  2098 usual for resolution.  Rare INCOMPATIBILITY.
  2099 
  2100 * Renamed varify/unvarify operations to varify_global/unvarify_global
  2101 to emphasize that these only work in a global situation (which is
  2102 quite rare).
  2103 
  2104 * Curried take and drop in library.ML; negative length is interpreted
  2105 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  2106 
  2107 * Proof terms: type substitutions on proof constants now use canonical
  2108 order of type variables.  INCOMPATIBILITY for tools working with proof
  2109 terms.
  2110 
  2111 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  2112 may no longer carry premises.  User-level specifications are
  2113 transformed accordingly by Thm.add_axiom/add_def.
  2114 
  2115 
  2116 *** System ***
  2117 
  2118 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  2119 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  2120 proof terms are enabled unconditionally in the new HOL-Proofs image.
  2121 
  2122 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  2123 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  2124 respectively.
  2125 
  2126 * Old lib/scripts/polyml-platform is superseded by the
  2127 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  2128 variant, even on a 64 bit machine.  The following example setting
  2129 prefers 64 bit if available:
  2130 
  2131   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  2132 
  2133 * The preliminary Isabelle/jEdit application demonstrates the emerging
  2134 Isabelle/Scala layer for advanced prover interaction and integration.
  2135 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  2136 component.
  2137 
  2138 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  2139 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  2140 similar to the default assignment of the document preparation system
  2141 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  2142 provides some operations for direct access to the font without asking
  2143 the user for manual installation.
  2144 
  2145 
  2146 
  2147 New in Isabelle2009-1 (December 2009)
  2148 -------------------------------------
  2149 
  2150 *** General ***
  2151 
  2152 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  2153 one backslash should be used, even in ML sources.
  2154 
  2155 
  2156 *** Pure ***
  2157 
  2158 * Locale interpretation propagates mixins along the locale hierarchy.
  2159 The currently only available mixins are the equations used to map
  2160 local definitions to terms of the target domain of an interpretation.
  2161 
  2162 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  2163 loc" to print all interpretations of locale "loc" in the theory.
  2164 Interpretations in proofs are not shown.
  2165 
  2166 * Thoroughly revised locales tutorial.  New section on conditional
  2167 interpretation.
  2168 
  2169 * On instantiation of classes, remaining undefined class parameters
  2170 are formally declared.  INCOMPATIBILITY.
  2171 
  2172 
  2173 *** Document preparation ***
  2174 
  2175 * New generalized style concept for printing terms: @{foo (style) ...}
  2176 instead of @{foo_style style ...}  (old form is still retained for
  2177 backward compatibility).  Styles can be also applied for
  2178 antiquotations prop, term_type and typeof.
  2179 
  2180 
  2181 *** HOL ***
  2182 
  2183 * New proof method "smt" for a combination of first-order logic with
  2184 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  2185 fixed-size bitvectors; there is also basic support for higher-order
  2186 features (esp. lambda abstractions).  It is an incomplete decision
  2187 procedure based on external SMT solvers using the oracle mechanism;
  2188 for the SMT solver Z3, this method is proof-producing.  Certificates
  2189 are provided to avoid calling the external solvers solely for
  2190 re-checking proofs.  Due to a remote SMT service there is no need for
  2191 installing SMT solvers locally.  See src/HOL/SMT.
  2192 
  2193 * New commands to load and prove verification conditions generated by
  2194 the Boogie program verifier or derived systems (e.g. the Verifying C
  2195 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  2196 
  2197 * New counterexample generator tool 'nitpick' based on the Kodkod
  2198 relational model finder.  See src/HOL/Tools/Nitpick and
  2199 src/HOL/Nitpick_Examples.
  2200 
  2201 * New commands 'code_pred' and 'values' to invoke the predicate
  2202 compiler and to enumerate values of inductive predicates.
  2203 
  2204 * A tabled implementation of the reflexive transitive closure.
  2205 
  2206 * New implementation of quickcheck uses generic code generator;
  2207 default generators are provided for all suitable HOL types, records
  2208 and datatypes.  Old quickcheck can be re-activated importing theory
  2209 Library/SML_Quickcheck.
  2210 
  2211 * New testing tool Mirabelle for automated proof tools.  Applies
  2212 several tools and tactics like sledgehammer, metis, or quickcheck, to
  2213 every proof step in a theory.  To be used in batch mode via the
  2214 "mirabelle" utility.
  2215 
  2216 * New proof method "sos" (sum of squares) for nonlinear real
  2217 arithmetic (originally due to John Harison). It requires theory
  2218 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  2219 works well in practice on quantifier-free real arithmetic with +, -,
  2220 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  2221 inequalities between polynomials.  It makes use of external
  2222 semidefinite programming solvers.  Method "sos" generates a
  2223 certificate that can be pasted into the proof thus avoiding the need
  2224 to call an external tool every time the proof is checked.  See
  2225 src/HOL/Library/Sum_Of_Squares.
  2226 
  2227 * New method "linarith" invokes existing linear arithmetic decision
  2228 procedure only.
  2229 
  2230 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  2231 
  2232 * New Sledgehammer option "Full Types" in Proof General settings menu.
  2233 Causes full type information to be output to the ATPs.  This slows
  2234 ATPs down considerably but eliminates a source of unsound "proofs"
  2235 that fail later.
  2236 
  2237 * New method "metisFT": A version of metis that uses full type
  2238 information in order to avoid failures of proof reconstruction.
  2239 
  2240 * New evaluator "approximate" approximates an real valued term using
  2241 the same method as the approximation method.
  2242 
  2243 * Method "approximate" now supports arithmetic expressions as
  2244 boundaries of intervals and implements interval splitting and Taylor
  2245 series expansion.
  2246 
  2247 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2248 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2249 
  2250 * New theory SupInf of the supremum and infimum operators for sets of
  2251 reals.
  2252 
  2253 * New theory Probability, which contains a development of measure
  2254 theory, eventually leading to Lebesgue integration and probability.
  2255 
  2256 * Extended Multivariate Analysis to include derivation and Brouwer's
  2257 fixpoint theorem.
  2258 
  2259 * Reorganization of number theory, INCOMPATIBILITY:
  2260   - new number theory development for nat and int, in theories Divides
  2261     and GCD as well as in new session Number_Theory
  2262   - some constants and facts now suffixed with _nat and _int
  2263     accordingly
  2264   - former session NumberTheory now named Old_Number_Theory, including
  2265     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2266   - moved theory Pocklington from src/HOL/Library to
  2267     src/HOL/Old_Number_Theory
  2268 
  2269 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2270 lcm of finite and infinite sets. It is shown that they form a complete
  2271 lattice.
  2272 
  2273 * Class semiring_div requires superclass no_zero_divisors and proof of
  2274 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2275 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2276 generalized to class semiring_div, subsuming former theorems
  2277 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2278 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2279 INCOMPATIBILITY.
  2280 
  2281 * Refinements to lattice classes and sets:
  2282   - less default intro/elim rules in locale variant, more default
  2283     intro/elim rules in class variant: more uniformity
  2284   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2285     le_inf_iff
  2286   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2287     sup_aci)
  2288   - renamed ACI to inf_sup_aci
  2289   - new class "boolean_algebra"
  2290   - class "complete_lattice" moved to separate theory
  2291     "Complete_Lattice"; corresponding constants (and abbreviations)
  2292     renamed and with authentic syntax:
  2293     Set.Inf ~>    Complete_Lattice.Inf
  2294     Set.Sup ~>    Complete_Lattice.Sup
  2295     Set.INFI ~>   Complete_Lattice.INFI
  2296     Set.SUPR ~>   Complete_Lattice.SUPR
  2297     Set.Inter ~>  Complete_Lattice.Inter
  2298     Set.Union ~>  Complete_Lattice.Union
  2299     Set.INTER ~>  Complete_Lattice.INTER
  2300     Set.UNION ~>  Complete_Lattice.UNION
  2301   - authentic syntax for
  2302     Set.Pow
  2303     Set.image
  2304   - mere abbreviations:
  2305     Set.empty               (for bot)
  2306     Set.UNIV                (for top)
  2307     Set.inter               (for inf, formerly Set.Int)
  2308     Set.union               (for sup, formerly Set.Un)
  2309     Complete_Lattice.Inter  (for Inf)
  2310     Complete_Lattice.Union  (for Sup)
  2311     Complete_Lattice.INTER  (for INFI)
  2312     Complete_Lattice.UNION  (for SUPR)
  2313   - object-logic definitions as far as appropriate
  2314 
  2315 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2316 Un_subset_iff are explicitly deleted as default simp rules; then also
  2317 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2318 deleted to achieve the desired effect.
  2319 
  2320 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2321 rules by default any longer; the same applies to min_max.inf_absorb1
  2322 etc.  INCOMPATIBILITY.
  2323 
  2324 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2325 pred_set_conv by default.  INCOMPATIBILITY.
  2326 
  2327 * Power operations on relations and functions are now one dedicated
  2328 constant "compow" with infix syntax "^^".  Power operation on
  2329 multiplicative monoids retains syntax "^" and is now defined generic
  2330 in class power.  INCOMPATIBILITY.
  2331 
  2332 * Relation composition "R O S" now has a more standard argument order:
  2333 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2334 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2335 break, since the O_assoc rule was not rewritten like this.  Fix using
  2336 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2337 
  2338 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2339 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2340 INCOMPATIBILITY.
  2341 
  2342 * Most rules produced by inductive and datatype package have mandatory
  2343 prefixes.  INCOMPATIBILITY.
  2344 
  2345 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2346 the attribute of the same name.  Each of the theorems in the list
  2347 DERIV_intros assumes composition with an additional function and
  2348 matches a variable to the derivative, which has to be solved by the
  2349 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2350 of most elementary terms.  Former Maclauren.DERIV_tac and
  2351 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2352 INCOMPATIBILITY.
  2353 
  2354 * Code generator attributes follow the usual underscore convention:
  2355     code_unfold     replaces    code unfold
  2356     code_post       replaces    code post
  2357     etc.
  2358   INCOMPATIBILITY.
  2359 
  2360 * Renamed methods:
  2361     sizechange -> size_change
  2362     induct_scheme -> induction_schema
  2363   INCOMPATIBILITY.
  2364 
  2365 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2366 INCOMPATIBILITY, use "undefined" directly.
  2367 
  2368 * Renamed theorems:
  2369     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2370     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2371     Suc_plus1 -> Suc_eq_plus1
  2372     *anti_sym -> *antisym*
  2373     vector_less_eq_def -> vector_le_def
  2374   INCOMPATIBILITY.
  2375 
  2376 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2377 INCOMPATIBILITY.
  2378 
  2379 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2380 INCOMPATIBILITY.
  2381 
  2382 
  2383 *** HOLCF ***
  2384 
  2385 * Theory Representable defines a class "rep" of domains that are
  2386 representable (via an ep-pair) in the universal domain type "udom".
  2387 Instances are provided for all type constructors defined in HOLCF.
  2388 
  2389 * The 'new_domain' command is a purely definitional version of the
  2390 domain package, for representable domains.  Syntax is identical to the
  2391 old domain package.  The 'new_domain' package also supports indirect
  2392 recursion using previously-defined type constructors.  See
  2393 src/HOLCF/ex/New_Domain.thy for examples.
  2394 
  2395 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2396 on the left-hand side of an equation, and then performs
  2397 simplification.  Rewriting is done using rules declared with the
  2398 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2399 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2400 
  2401 * The pattern-match compiler in 'fixrec' can now handle constructors
  2402 with HOL function types.  Pattern-match combinators for the Pair
  2403 constructor are pre-configured.
  2404 
  2405 * The 'fixrec' package now produces better fixed-point induction rules
  2406 for mutually-recursive definitions:  Induction rules have conclusions
  2407 of the form "P foo bar" instead of "P <foo, bar>".
  2408 
  2409 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2410 been renamed to "below".  The name "below" now replaces "less" in many
  2411 theorem names.  (Legacy theorem names using "less" are still supported
  2412 as well.)
  2413 
  2414 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2415 patterns can be used to generate strictness rules, or to make
  2416 functions more strict (much like the bang-patterns supported by the
  2417 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2418 examples.
  2419 
  2420 
  2421 *** ML ***
  2422 
  2423 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2424 errors and run-time exceptions, including detailed source positions.
  2425 
  2426 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2427 identified entries, with some additional information such as source
  2428 position, logical grouping etc.
  2429 
  2430 * Theory and context data is now introduced by the simplified and
  2431 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2432 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2433 copy operation) is still available for some time.
  2434 
  2435 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2436 provides a high-level programming interface to synchronized state
  2437 variables with atomic update.  This works via pure function
  2438 application within a critical section -- its runtime should be as
  2439 short as possible; beware of deadlocks if critical code is nested,
  2440 either directly or indirectly via other synchronized variables!
  2441 
  2442 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2443 wraps raw ML references, explicitly indicating their non-thread-safe
  2444 behaviour.  The Isar toplevel keeps this structure open, to
  2445 accommodate Proof General as well as quick and dirty interactive
  2446 experiments with references.
  2447 
  2448 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2449 parallel tactical reasoning.
  2450 
  2451 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2452 are similar to SUBPROOF, but are slightly more flexible: only the
  2453 specified parts of the subgoal are imported into the context, and the
  2454 body tactic may introduce new subgoals and schematic variables.
  2455 
  2456 * Old tactical METAHYPS, which does not observe the proof context, has
  2457 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2458 or Subgoal.FOCUS etc.
  2459 
  2460 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2461 functors have their own ML name space there is no point to mark them
  2462 separately.)  Minor INCOMPATIBILITY.
  2463 
  2464 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2465 
  2466 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2467 INCOMPATIBILITY.
  2468 
  2469 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2470 mode, which avoids critical setmp.
  2471 
  2472 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2473 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2474 Attrib/Method.setup introduced in Isabelle2009.
  2475 
  2476 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2477 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2478 last resort.  INCOMPATIBILITY.
  2479 
  2480 * Display.pretty_thm now requires a proper context (cf. former
  2481 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2482 or even Display.pretty_thm_without_context as last resort.
  2483 INCOMPATIBILITY.
  2484 
  2485 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2486 Syntax.pretty_typ/term directly, preferably with proper context
  2487 instead of global theory.
  2488 
  2489 
  2490 *** System ***
  2491 
  2492 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2493 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2494 usedir option -q.
  2495 
  2496 * Support for additional "Isabelle components" via etc/components, see
  2497 also the system manual.
  2498 
  2499 * The isabelle makeall tool now operates on all components with
  2500 IsaMakefile, not just hardwired "logics".
  2501 
  2502 * Removed "compress" option from isabelle-process and isabelle usedir;
  2503 this is always enabled.
  2504 
  2505 * Discontinued support for Poly/ML 4.x versions.
  2506 
  2507 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2508 on a given logic image.  This requires the lighttpd webserver and is
  2509 currently supported on Linux only.
  2510 
  2511 
  2512 
  2513 New in Isabelle2009 (April 2009)
  2514 --------------------------------
  2515 
  2516 *** General ***
  2517 
  2518 * Simplified main Isabelle executables, with less surprises on
  2519 case-insensitive file-systems (such as Mac OS).
  2520 
  2521   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2522     "isatool."
  2523 
  2524   - The former "isabelle" alias for "isabelle-process" has been
  2525     removed (should rarely occur to regular users).
  2526 
  2527   - The former "isabelle-interface" and its alias "Isabelle" have been
  2528     removed (interfaces are now regular Isabelle tools).
  2529 
  2530 Within scripts and make files, the Isabelle environment variables
  2531 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2532 respectively.  (The latter are still available as legacy feature.)
  2533 
  2534 The old isabelle-interface wrapper could react in confusing ways if
  2535 the interface was uninstalled or changed otherwise.  Individual
  2536 interface tool configuration is now more explicit, see also the
  2537 Isabelle system manual.  In particular, Proof General is now available
  2538 via "isabelle emacs".
  2539 
  2540 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2541 purge installed copies of Isabelle executables and re-run "isabelle
  2542 install -p ...", or use symlinks.
  2543 
  2544 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2545 old ~/isabelle, which was slightly non-standard and apt to cause
  2546 surprises on case-insensitive file-systems (such as Mac OS).
  2547 
  2548 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2549 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2550 care is required when using older releases of Isabelle.  Note that
  2551 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2552 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2553 
  2554 * Proofs of fully specified statements are run in parallel on
  2555 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2556 a regular 4-core machine, if the initial heap space is made reasonably
  2557 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2558 
  2559 * The main reference manuals ("isar-ref", "implementation", and
  2560 "system") have been updated and extended.  Formally checked references
  2561 as hyperlinks are now available uniformly.
  2562 
  2563 
  2564 *** Pure ***
  2565 
  2566 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2567 respects.  The most important changes are listed below.  See the
  2568 Tutorial on Locales ("locales" manual) for details.
  2569 
  2570 - In locale expressions, instantiation replaces renaming.  Parameters
  2571 must be declared in a for clause.  To aid compatibility with previous
  2572 parameter inheritance, in locale declarations, parameters that are not
  2573 'touched' (instantiation position "_" or omitted) are implicitly added
  2574 with their syntax at the beginning of the for clause.
  2575 
  2576 - Syntax from abbreviations and definitions in locales is available in
  2577 locale expressions and context elements.  The latter is particularly
  2578 useful in locale declarations.
  2579 
  2580 - More flexible mechanisms to qualify names generated by locale
  2581 expressions.  Qualifiers (prefixes) may be specified in locale
  2582 expressions, and can be marked as mandatory (syntax: "name!:") or
  2583 optional (syntax "name?:").  The default depends for plain "name:"
  2584 depends on the situation where a locale expression is used: in
  2585 commands 'locale' and 'sublocale' prefixes are optional, in
  2586 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2587 implicit qualifiers derived from the parameter names of a locale are
  2588 no longer generated.
  2589 
  2590 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2591 instantiation clause in "interpretation" and "interpret" (square
  2592 brackets) is no longer available.  Use locale expressions.
  2593 
  2594 - When converting proof scripts, mandatory qualifiers in
  2595 'interpretation' and 'interpret' should be retained by default, even
  2596 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2597 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2598 in locale expressions range over a single locale instance only.
  2599 
  2600 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2601 In existing theorem specifications replace the includes element by the
  2602 respective context elements of the included locale, omitting those
  2603 that are already present in the theorem specification.  Multiple
  2604 assume elements of a locale should be replaced by a single one
  2605 involving the locale predicate.  In the proof body, declarations (most
  2606 notably theorems) may be regained by interpreting the respective
  2607 locales in the proof context as required (command "interpret").
  2608 
  2609 If using "includes" in replacement of a target solely because the
  2610 parameter types in the theorem are not as general as in the target,
  2611 consider declaring a new locale with additional type constraints on
  2612 the parameters (context element "constrains").
  2613 
  2614 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2615 
  2616 - Locale interpretation commands no longer attempt to simplify goal.
  2617 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2618 methods intro_locales and unfold_locales to clarify.
  2619 
  2620 - Locale interpretation commands no longer accept interpretation
  2621 attributes.  INCOMPATIBILITY.
  2622 
  2623 * Class declaration: so-called "base sort" must not be given in import
  2624 list any longer, but is inferred from the specification.  Particularly
  2625 in HOL, write
  2626 
  2627     class foo = ...
  2628 
  2629 instead of
  2630 
  2631     class foo = type + ...
  2632 
  2633 * Class target: global versions of theorems stemming do not carry a
  2634 parameter prefix any longer.  INCOMPATIBILITY.
  2635 
  2636 * Class 'instance' command no longer accepts attached definitions.
  2637 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2638 
  2639 * Recovered hiding of consts, which was accidentally broken in
  2640 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2641 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2642 
  2643 * Slightly more coherent Pure syntax, with updated documentation in
  2644 isar-ref manual.  Removed locales meta_term_syntax and
  2645 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2646 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2647 directly in regular applications.
  2648 
  2649 * There is a new syntactic category "float_const" for signed decimal
  2650 fractions (e.g. 123.45 or -123.45).
  2651 
  2652 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2653 interface with 'setup' command instead.
  2654 
  2655 * Command 'local_setup' is similar to 'setup', but operates on a local
  2656 theory context.
  2657 
  2658 * The 'axiomatization' command now only works within a global theory
  2659 context.  INCOMPATIBILITY.
  2660 
  2661 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2662 hypotheses.  Sorts required in the course of reasoning need to be
  2663 covered by the constraints in the initial statement, completed by the
  2664 type instance information of the background theory.  Non-trivial sort
  2665 hypotheses, which rarely occur in practice, may be specified via
  2666 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2667 
  2668   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2669 
  2670 The result contains an implicit sort hypotheses as before --
  2671 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2672 normalization.
  2673 
  2674 * Generalized Isar history, with support for linear undo, direct state
  2675 addressing etc.
  2676 
  2677 * Changed defaults for unify configuration options:
  2678 
  2679   unify_trace_bound = 50 (formerly 25)
  2680   unify_search_bound = 60 (formerly 30)
  2681 
  2682 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2683 
  2684   a) On theory merge, the last set of code equations for a particular
  2685      constant is taken (in accordance with the policy applied by other
  2686      parts of the code generator framework).
  2687 
  2688   b) Code equations stemming from explicit declarations (e.g. code
  2689      attribute) gain priority over default code equations stemming
  2690      from definition, primrec, fun etc.
  2691 
  2692 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2693 
  2694 * Unified theorem tables for both code generators.  Thus [code
  2695 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2696 
  2697 * Command 'find_consts' searches for constants based on type and name
  2698 patterns, e.g.
  2699 
  2700     find_consts "_ => bool"
  2701 
  2702 By default, matching is against subtypes, but it may be restricted to
  2703 the whole type.  Searching by name is possible.  Multiple queries are
  2704 conjunctive and queries may be negated by prefixing them with a
  2705 hyphen:
  2706 
  2707     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2708 
  2709 * New 'find_theorems' criterion "solves" matches theorems that
  2710 directly solve the current goal (modulo higher-order unification).
  2711 
  2712 * Auto solve feature for main theorem statements: whenever a new goal
  2713 is stated, "find_theorems solves" is called; any theorems that could
  2714 solve the lemma directly are listed as part of the goal state.
  2715 Cf. associated options in Proof General Isabelle settings menu,
  2716 enabled by default, with reasonable timeout for pathological cases of
  2717 higher-order unification.
  2718 
  2719 
  2720 *** Document preparation ***
  2721 
  2722 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2723 demanding keyword 'by' and supporting the full method expression
  2724 syntax just like the Isar command 'by'.
  2725 
  2726 
  2727 *** HOL ***
  2728 
  2729 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2730 points Main and Complex_Main remain as before.
  2731 
  2732 * Logic image HOL-Plain provides a minimal HOL with the most important
  2733 tools available (inductive, datatype, primrec, ...).  This facilitates
  2734 experimentation and tool development.  Note that user applications
  2735 (and library theories) should never refer to anything below theory
  2736 Main, as before.
  2737 
  2738 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2739 experimentation due to shorter build times.
  2740 
  2741 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2742 were previously part of former HOL-Complex.  Entry point Hyperreal
  2743 remains valid, but theories formerly using Complex_Main should now use
  2744 new entry point Hypercomplex.
  2745 
  2746 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2747 Posix processes.  Avoids potentially expensive forking of the ML
  2748 process.  New thread-based implementation also works on non-Unix
  2749 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2750 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2751 commands are covered in the isar-ref manual.
  2752 
  2753 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2754 sledgehammer without local ATP installation (Vampire etc.). Other
  2755 provers may be included via suitable ML wrappers, see also
  2756 src/HOL/ATP_Linkup.thy.
  2757 
  2758 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2759 menu.
  2760 
  2761 * The metis method no longer fails because the theorem is too trivial
  2762 (contains the empty clause).
  2763 
  2764 * The metis method now fails in the usual manner, rather than raising
  2765 an exception, if it determines that it cannot prove the theorem.
  2766 
  2767 * Method "coherent" implements a prover for coherent logic (see also
  2768 src/Tools/coherent.ML).
  2769 
  2770 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2771 "undefined" is the right choice to replace "arbitrary", though
  2772 logically there is no difference.  INCOMPATIBILITY.
  2773 
  2774 * Command "value" now integrates different evaluation mechanisms.  The
  2775 result of the first successful evaluation mechanism is printed.  In
  2776 square brackets a particular named evaluation mechanisms may be
  2777 specified (currently, [SML], [code] or [nbe]).  See further
  2778 src/HOL/ex/Eval_Examples.thy.
  2779 
  2780 * Normalization by evaluation now allows non-leftlinear equations.
  2781 Declare with attribute [code nbe].
  2782 
  2783 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2784 as the structured Isar versions "cases" and "induct", cf. the
  2785 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2786 are now presented as a list of individual projections
  2787 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2788 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2789 rare situations a different rule is selected --- notably nested tuple
  2790 elimination instead of former prod.exhaust: use explicit (case_tac t
  2791 rule: prod.exhaust) here.
  2792 
  2793 * Attributes "cases", "induct", "coinduct" support "del" option.
  2794 
  2795 * Removed fact "case_split_thm", which duplicates "case_split".
  2796 
  2797 * The option datatype has been moved to a new theory Option.  Renamed
  2798 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2799 
  2800 * New predicate "strict_mono" classifies strict functions on partial
  2801 orders.  With strict functions on linear orders, reasoning about
  2802 (in)equalities is facilitated by theorems "strict_mono_eq",
  2803 "strict_mono_less_eq" and "strict_mono_less".
  2804 
  2805 * Some set operations are now proper qualified constants with
  2806 authentic syntax.  INCOMPATIBILITY:
  2807 
  2808     op Int ~>   Set.Int
  2809     op Un ~>    Set.Un
  2810     INTER ~>    Set.INTER
  2811     UNION ~>    Set.UNION
  2812     Inter ~>    Set.Inter
  2813     Union ~>    Set.Union
  2814     {} ~>       Set.empty
  2815     UNIV ~>     Set.UNIV
  2816 
  2817 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2818 theory Set.
  2819 
  2820 * Auxiliary class "itself" has disappeared -- classes without any
  2821 parameter are treated as expected by the 'class' command.
  2822 
  2823 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2824 
  2825 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2826 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2827 
  2828 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2829 method "approximation".  It proves formulas on real values by using
  2830 interval arithmetic.  In the formulas are also the transcendental
  2831 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2832 allowed. For examples see
  2833 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2834 
  2835 * Theory "Reflection" now resides in HOL/Library.
  2836 
  2837 * Entry point to Word library now simply named "Word".
  2838 INCOMPATIBILITY.
  2839 
  2840 * Made source layout more coherent with logical distribution
  2841 structure:
  2842 
  2843     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2844     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2845     src/HOL/Library/GCD.thy ~> src/HOL/
  2846     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2847     src/HOL/Library/Parity.thy ~> src/HOL/
  2848     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2849     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2850     src/HOL/Real/Lubs.thy ~> src/HOL/
  2851     src/HOL/Real/PReal.thy ~> src/HOL/
  2852     src/HOL/Real/Rational.thy ~> src/HOL/
  2853     src/HOL/Real/RComplete.thy ~> src/HOL/
  2854     src/HOL/Real/RealDef.thy ~> src/HOL/
  2855     src/HOL/Real/RealPow.thy ~> src/HOL/
  2856     src/HOL/Real/Real.thy ~> src/HOL/
  2857     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2858     src/HOL/Complex/Complex.thy ~> src/HOL/
  2859     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2860     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2861     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2862     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2863     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2864     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2865     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2866     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2867     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2868     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2869     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2870     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2871     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2872     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2873     src/HOL/Real/Float ~> src/HOL/Library/
  2874     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2875     src/HOL/Real/RealVector.thy ~> src/HOL/
  2876 
  2877     src/HOL/arith_data.ML ~> src/HOL/Tools
  2878     src/HOL/hologic.ML ~> src/HOL/Tools
  2879     src/HOL/simpdata.ML ~> src/HOL/Tools
  2880     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2881     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2882     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2883     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2884     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2885     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2886     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2887 
  2888     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2889     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2890     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2891     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2892     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2893     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2894 
  2895 * If methods "eval" and "evaluation" encounter a structured proof
  2896 state with !!/==>, only the conclusion is evaluated to True (if
  2897 possible), avoiding strange error messages.
  2898 
  2899 * Method "sizechange" automates termination proofs using (a
  2900 modification of) the size-change principle.  Requires SAT solver.  See
  2901 src/HOL/ex/Termination.thy for examples.
  2902 
  2903 * Simplifier: simproc for let expressions now unfolds if bound
  2904 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2905 
  2906 * Method "arith": Linear arithmetic now ignores all inequalities when
  2907 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2908 
  2909 * New attribute "arith" for facts that should always be used
  2910 automatically by arithmetic. It is intended to be used locally in
  2911 proofs, e.g.
  2912 
  2913   assumes [arith]: "x > 0"
  2914 
  2915 Global usage is discouraged because of possible performance impact.
  2916 
  2917 * New classes "top" and "bot" with corresponding operations "top" and
  2918 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2919 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2920 
  2921 * Changed definition lemma "less_fun_def" in order to provide an
  2922 instance for preorders on functions; use lemma "less_le" instead.
  2923 INCOMPATIBILITY.
  2924 
  2925 * Theory Orderings: class "wellorder" moved here, with explicit
  2926 induction rule "less_induct" as assumption.  For instantiation of
  2927 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2928 INCOMPATIBILITY.
  2929 
  2930 * Theory Orderings: added class "preorder" as superclass of "order".
  2931 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2932 etc. slightly changed.  Some theorems named order_class.* now named
  2933 preorder_class.*.
  2934 
  2935 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2936 "diag" to "Id_on".
  2937 
  2938 * Theory Finite_Set: added a new fold combinator of type
  2939 
  2940   ('a => 'b => 'b) => 'b => 'a set => 'b
  2941 
  2942 Occasionally this is more convenient than the old fold combinator
  2943 which is now defined in terms of the new one and renamed to
  2944 fold_image.
  2945 
  2946 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2947 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2948 extended with further lemmas!).  At the moment both still exist but
  2949 the former will disappear at some point.
  2950 
  2951 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2952 class recpower.  Type-specific simp rules for various recpower types
  2953 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2954 
  2955 rat_power_0    -> power_0
  2956 rat_power_Suc  -> power_Suc
  2957 realpow_0      -> power_0
  2958 realpow_Suc    -> power_Suc
  2959 complexpow_0   -> power_0
  2960 complexpow_Suc -> power_Suc
  2961 power_poly_0   -> power_0
  2962 power_poly_Suc -> power_Suc
  2963 
  2964 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2965 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2966 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2967 of lemmas from Divides has been generalized from nat to class
  2968 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2969 renames resulting from duplicate elimination:
  2970 
  2971     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2972     zero_dvd_iff ~>         dvd_0_left_iff
  2973     dvd_0 ~>                dvd_0_right
  2974     DIVISION_BY_ZERO_DIV ~> div_by_0
  2975     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2976     mult_div ~>             div_mult_self2_is_id
  2977     mult_mod ~>             mod_mult_self2_is_0
  2978 
  2979 * Theory IntDiv: removed many lemmas that are instances of class-based
  2980 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2981 rename old lemmas as follows:
  2982 
  2983 dvd_diff               -> nat_dvd_diff
  2984 dvd_zminus_iff         -> dvd_minus_iff
  2985 mod_add1_eq            -> mod_add_eq
  2986 mod_mult1_eq           -> mod_mult_right_eq
  2987 mod_mult1_eq'          -> mod_mult_left_eq
  2988 mod_mult_distrib_mod   -> mod_mult_eq
  2989 nat_mod_add_left_eq    -> mod_add_left_eq
  2990 nat_mod_add_right_eq   -> mod_add_right_eq
  2991 nat_mod_div_trivial    -> mod_div_trivial
  2992 nat_mod_mod_trivial    -> mod_mod_trivial
  2993 zdiv_zadd_self1        -> div_add_self1
  2994 zdiv_zadd_self2        -> div_add_self2
  2995 zdiv_zmult_self1       -> div_mult_self2_is_id
  2996 zdiv_zmult_self2       -> div_mult_self1_is_id
  2997 zdvd_triv_left         -> dvd_triv_left
  2998 zdvd_triv_right        -> dvd_triv_right
  2999 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  3000 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  3001 zmod_zadd_left_eq      -> mod_add_left_eq
  3002 zmod_zadd_right_eq     -> mod_add_right_eq
  3003 zmod_zadd_self1        -> mod_add_self1
  3004 zmod_zadd_self2        -> mod_add_self2
  3005 zmod_zadd1_eq          -> mod_add_eq
  3006 zmod_zdiff1_eq         -> mod_diff_eq
  3007 zmod_zdvd_zmod         -> mod_mod_cancel
  3008 zmod_zmod_cancel       -> mod_mod_cancel
  3009 zmod_zmult_self1       -> mod_mult_self2_is_0
  3010 zmod_zmult_self2       -> mod_mult_self1_is_0
  3011 zmod_1                 -> mod_by_1
  3012 zdiv_1                 -> div_by_1
  3013 zdvd_abs1              -> abs_dvd_iff
  3014 zdvd_abs2              -> dvd_abs_iff
  3015 zdvd_refl              -> dvd_refl
  3016 zdvd_trans             -> dvd_trans
  3017 zdvd_zadd              -> dvd_add
  3018 zdvd_zdiff             -> dvd_diff
  3019 zdvd_zminus_iff        -> dvd_minus_iff
  3020 zdvd_zminus2_iff       -> minus_dvd_iff
  3021 zdvd_zmultD            -> dvd_mult_right
  3022 zdvd_zmultD2           -> dvd_mult_left
  3023 zdvd_zmult_mono        -> mult_dvd_mono
  3024 zdvd_0_right           -> dvd_0_right
  3025 zdvd_0_left            -> dvd_0_left_iff
  3026 zdvd_1_left            -> one_dvd
  3027 zminus_dvd_iff         -> minus_dvd_iff
  3028 
  3029 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  3030 
  3031 * The real numbers offer decimal input syntax: 12.34 is translated
  3032 into 1234/10^2. This translation is not reversed upon output.
  3033 
  3034 * Theory Library/Polynomial defines an abstract type 'a poly of
  3035 univariate polynomials with coefficients of type 'a.  In addition to
  3036 the standard ring operations, it also supports div and mod.  Code
  3037 generation is also supported, using list-style constructors.
  3038 
  3039 * Theory Library/Inner_Product defines a class of real_inner for real
  3040 inner product spaces, with an overloaded operation inner :: 'a => 'a
  3041 => real.  Class real_inner is a subclass of real_normed_vector from
  3042 theory RealVector.
  3043 
  3044 * Theory Library/Product_Vector provides instances for the product
  3045 type 'a * 'b of several classes from RealVector and Inner_Product.
  3046 Definitions of addition, subtraction, scalar multiplication, norms,
  3047 and inner products are included.
  3048 
  3049 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  3050 addition to the field operations, numerals and case syntax are also
  3051 supported.
  3052 
  3053 * Theory Library/Diagonalize provides constructive version of Cantor's
  3054 first diagonalization argument.
  3055 
  3056 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  3057 zlcm (for int); carried together from various gcd/lcm developements in
  3058 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  3059 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  3060 may recover tupled syntax as follows:
  3061 
  3062     hide (open) const gcd
  3063     abbreviation gcd where
  3064       "gcd == (%(a, b). GCD.gcd a b)"
  3065     notation (output)
  3066       GCD.gcd ("gcd '(_, _')")
  3067 
  3068 The same works for lcm, zgcd, zlcm.
  3069 
  3070 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  3071 instantiations for algebraic structures.  Removed some duplicate
  3072 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  3073 
  3074 * ML antiquotation @{code} takes a constant as argument and generates
  3075 corresponding code in background and inserts name of the corresponding
  3076 resulting ML value/function/datatype constructor binding in place.
  3077 All occurrences of @{code} with a single ML block are generated
  3078 simultaneously.  Provides a generic and safe interface for
  3079 instrumentalizing code generation.  See
  3080 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  3081 In future you ought to refrain from ad-hoc compiling generated SML
  3082 code on the ML toplevel.  Note that (for technical reasons) @{code}
  3083 cannot refer to constants for which user-defined serializations are
  3084 set.  Refer to the corresponding ML counterpart directly in that
  3085 cases.
  3086 
  3087 * Command 'rep_datatype': instead of theorem names the command now
  3088 takes a list of terms denoting the constructors of the type to be
  3089 represented as datatype.  The characteristic theorems have to be
  3090 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  3091 have disappeared in favour of existing ones:
  3092 
  3093     unit_induct                 ~> unit.induct
  3094     prod_induct                 ~> prod.induct
  3095     sum_induct                  ~> sum.induct
  3096     Suc_Suc_eq                  ~> nat.inject
  3097     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  3098 
  3099 
  3100 *** HOL-Algebra ***
  3101 
  3102 * New locales for orders and lattices where the equivalence relation
  3103 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  3104 locales use a record structure with field eq for the equivalence.
  3105 
  3106 * New theory of factorial domains.
  3107 
  3108 * Units_l_inv and Units_r_inv are now simp rules by default.
  3109 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  3110 and/or r_inv will now also require deletion of these lemmas.
  3111 
  3112 * Renamed the following theorems, INCOMPATIBILITY:
  3113 
  3114 UpperD ~> Upper_memD
  3115 LowerD ~> Lower_memD
  3116 least_carrier ~> least_closed
  3117 greatest_carrier ~> greatest_closed
  3118 greatest_Lower_above ~> greatest_Lower_below
  3119 one_zero ~> carrier_one_zero
  3120 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  3121 
  3122 
  3123 *** HOL-Nominal ***
  3124 
  3125 * Nominal datatypes can now contain type-variables.
  3126 
  3127 * Commands 'nominal_inductive' and 'equivariance' work with local
  3128 theory targets.
  3129 
  3130 * Nominal primrec can now works with local theory targets and its
  3131 specification syntax now conforms to the general format as seen in
  3132 'inductive' etc.
  3133 
  3134 * Method "perm_simp" honours the standard simplifier attributes
  3135 (no_asm), (no_asm_use) etc.
  3136 
  3137 * The new predicate #* is defined like freshness, except that on the
  3138 left hand side can be a set or list of atoms.
  3139 
  3140 * Experimental command 'nominal_inductive2' derives strong induction
  3141 principles for inductive definitions.  In contrast to
  3142 'nominal_inductive', which can only deal with a fixed number of
  3143 binders, it can deal with arbitrary expressions standing for sets of
  3144 atoms to be avoided.  The only inductive definition we have at the
  3145 moment that needs this generalisation is the typing rule for Lets in
  3146 the algorithm W:
  3147 
  3148  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  3149  -----------------------------------------------------------------
  3150          Gamma |- Let x be t1 in t2 : T2
  3151 
  3152 In this rule one wants to avoid all the binders that are introduced by
  3153 "close Gamma T1".  We are looking for other examples where this
  3154 feature might be useful.  Please let us know.
  3155 
  3156 
  3157 *** HOLCF ***
  3158 
  3159 * Reimplemented the simplification procedure for proving continuity
  3160 subgoals.  The new simproc is extensible; users can declare additional
  3161 continuity introduction rules with the attribute [cont2cont].
  3162 
  3163 * The continuity simproc now uses a different introduction rule for
  3164 solving continuity subgoals on terms with lambda abstractions.  In
  3165 some rare cases the new simproc may fail to solve subgoals that the
  3166 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  3167 Potential INCOMPATIBILITY.
  3168 
  3169 * Command 'fixrec': specification syntax now conforms to the general
  3170 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  3171 examples.  INCOMPATIBILITY.
  3172 
  3173 
  3174 *** ZF ***
  3175 
  3176 * Proof of Zorn's Lemma for partial orders.
  3177 
  3178 
  3179 *** ML ***
  3180 
  3181 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  3182 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  3183 depends on multithreading, so timouts will not work before Poly/ML
  3184 5.2.1!
  3185 
  3186 * High-level support for concurrent ML programming, see
  3187 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  3188 particularly convenient to organize independent functional
  3189 computations.  The concept of "synchronized variables" provides a
  3190 higher-order interface for components with shared state, avoiding the
  3191 delicate details of mutexes and condition variables.  (Requires
  3192 Poly/ML 5.2.1 or later.)
  3193 
  3194 * ML bindings produced via Isar commands are stored within the Isar
  3195 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  3196 become thread-safe and work with undo as expected (concerning
  3197 top-level bindings, not side-effects on global references).
  3198 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  3199 compiler at runtime; really global bindings need to be given outside a
  3200 theory.  (Requires Poly/ML 5.2 or later.)
  3201 
  3202 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  3203 context.  Top-level ML bindings are stored within the proof context in
  3204 a purely sequential fashion, disregarding the nested proof structure.
  3205 ML bindings introduced by 'ML_prf' are discarded at the end of the
  3206 proof.  (Requires Poly/ML 5.2 or later.)
  3207 
  3208 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  3209 and Method.setup, as well as Isar commands 'attribute_setup' and
  3210 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  3211 existing code accordingly, or use plain 'setup' together with old
  3212 Method.add_method.
  3213 
  3214 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  3215 to 'a -> thm, while results are always tagged with an authentic oracle
  3216 name.  The Isar command 'oracle' is now polymorphic, no argument type
  3217 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  3218 accordingly.  Note that extra performance may be gained by producing
  3219 the cterm carefully, avoiding slow Thm.cterm_of.
  3220 
  3221 * Simplified interface for defining document antiquotations via
  3222 ThyOutput.antiquotation, ThyOutput.output, and optionally
  3223 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  3224 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  3225 examples.
  3226 
  3227 * More systematic treatment of long names, abstract name bindings, and
  3228 name space operations.  Basic operations on qualified names have been
  3229 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  3230 Long_Name.append.  Old type bstring has been mostly replaced by
  3231 abstract type binding (see structure Binding), which supports precise
  3232 qualification by packages and local theory targets, as well as proper
  3233 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  3234 bstring values into Binding.name, or better pass through abstract
  3235 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3236 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3237 
  3238 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3239 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3240 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3241 
  3242 * Disposed old type and term read functions (Sign.read_def_typ,
  3243 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3244 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3245 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3246 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3247 resort for legacy applications.
  3248 
  3249 * Disposed old declarations, tactics, tactic combinators that refer to
  3250 the simpset or claset of an implicit theory (such as Addsimps,
  3251 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3252 embedded ML text, or local_simpset_of with a proper context passed as
  3253 explicit runtime argument.
  3254 
  3255 * Rules and tactics that read instantiations (read_instantiate,
  3256 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3257 context, which is required for parsing and type-checking.  Moreover,
  3258 the variables are specified as plain indexnames, not string encodings
  3259 thereof.  INCOMPATIBILITY.
  3260 
  3261 * Generic Toplevel.add_hook interface allows to analyze the result of
  3262 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3263 for theorem dependency output of transactions resulting in a new
  3264 theory state.
  3265 
  3266 * ML antiquotations: block-structured compilation context indicated by
  3267 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3268 
  3269   @{binding name}                         - basic name binding
  3270   @{let ?pat = term}                      - term abbreviation (HO matching)
  3271   @{note name = fact}                     - fact abbreviation
  3272   @{thm fact}                             - singleton fact (with attributes)
  3273   @{thms fact}                            - general fact (with attributes)
  3274   @{lemma prop by method}                 - singleton goal
  3275   @{lemma prop by meth1 meth2}            - singleton goal
  3276   @{lemma prop1 ... propN by method}      - general goal
  3277   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3278   @{lemma (open) ...}                     - open derivation
  3279 
  3280 
  3281 *** System ***
  3282 
  3283 * The Isabelle "emacs" tool provides a specific interface to invoke
  3284 Proof General / Emacs, with more explicit failure if that is not
  3285 installed (the old isabelle-interface script silently falls back on
  3286 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3287 installation location of the Proof General distribution.
  3288 
  3289 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3290 the Isabelle process into a JVM/Scala application.  See
  3291 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3292 process wrapper has been discontinued.)
  3293 
  3294 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3295 
  3296 * Various status messages (with exact source position information) are
  3297 emitted, if proper markup print mode is enabled.  This allows
  3298 user-interface components to provide detailed feedback on internal
  3299 prover operations.
  3300 
  3301 
  3302 
  3303 New in Isabelle2008 (June 2008)
  3304 -------------------------------
  3305 
  3306 *** General ***
  3307 
  3308 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3309 and updated, with formally checked references as hyperlinks.
  3310 
  3311 * Theory loader: use_thy (and similar operations) no longer set the
  3312 implicit ML context, which was occasionally hard to predict and in
  3313 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3314 provides a proper context already.
  3315 
  3316 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3317 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3318 'use' within a theory file will do the job.
  3319 
  3320 * Name space merge now observes canonical order, i.e. the second space
  3321 is inserted into the first one, while existing entries in the first
  3322 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3323 swap theory imports.
  3324 
  3325 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3326 INCOMPATIBILITY in identifier syntax etc.
  3327 
  3328 * Outer syntax: string tokens no longer admit escaped white space,
  3329 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3330 white space without escapes.
  3331 
  3332 * Outer syntax: string tokens may contain arbitrary character codes
  3333 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3334 "foo_bar".
  3335 
  3336 
  3337 *** Pure ***
  3338 
  3339 * Context-dependent token translations.  Default setup reverts locally
  3340 fixed variables, and adds hilite markup for undeclared frees.
  3341 
  3342 * Unused theorems can be found using the new command 'unused_thms'.
  3343 There are three ways of invoking it:
  3344 
  3345 (1) unused_thms
  3346      Only finds unused theorems in the current theory.
  3347 
  3348 (2) unused_thms thy_1 ... thy_n -
  3349      Finds unused theorems in the current theory and all of its ancestors,
  3350      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3351 
  3352 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3353      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3354      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3355      their ancestors.
  3356 
  3357 In order to increase the readability of the list produced by
  3358 unused_thms, theorems that have been created by a particular instance
  3359 of a theory command such as 'inductive' or 'function' are considered
  3360 to belong to the same "group", meaning that if at least one theorem in
  3361 this group is used, the other theorems in the same group are no longer
  3362 reported as unused.  Moreover, if all theorems in the group are
  3363 unused, only one theorem in the group is displayed.
  3364 
  3365 Note that proof objects have to be switched on in order for
  3366 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3367 usually the case when using Proof General with the default settings).
  3368 
  3369 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3370 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3371 duplicate fact bindings, or even accidental fact duplications.  Note
  3372 that tools may maintain dynamically scoped facts systematically, using
  3373 PureThy.add_thms_dynamic.
  3374 
  3375 * Command 'hide' now allows to hide from "fact" name space as well.
  3376 
  3377 * Eliminated destructive theorem database, simpset, claset, and
  3378 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3379 update of theories within ML code.
  3380 
  3381 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3382 INCOMPATIBILITY, object-logics depending on former Pure require
  3383 additional setup PureThy.old_appl_syntax_setup; object-logics
  3384 depending on former CPure need to refer to Pure.
  3385 
  3386 * Commands 'use' and 'ML' are now purely functional, operating on
  3387 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3388 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3389 INCOMPATIBILITY.
  3390 
  3391 * Command 'setup': discontinued implicit version with ML reference.
  3392 
  3393 * Instantiation target allows for simultaneous specification of class
  3394 instance operations together with an instantiation proof.
  3395 Type-checking phase allows to refer to class operations uniformly.
  3396 See src/HOL/Complex/Complex.thy for an Isar example and
  3397 src/HOL/Library/Eval.thy for an ML example.
  3398 
  3399 * Indexing of literal facts: be more serious about including only
  3400 facts from the visible specification/proof context, but not the
  3401 background context (locale etc.).  Affects `prop` notation and method
  3402 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3403 situations.
  3404 
  3405 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3406 "(open)" option, which used to expose internal bound variables to the
  3407 proof text.
  3408 
  3409 * Isar statements: removed obsolete case "rule_context".
  3410 INCOMPATIBILITY, better use explicit fixes/assumes.
  3411 
  3412 * Locale proofs: default proof step now includes 'unfold_locales';
  3413 hence 'proof' without argument may be used to unfold locale
  3414 predicates.
  3415 
  3416 
  3417 *** Document preparation ***
  3418 
  3419 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3420 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3421 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3422 spot); renamed link color from "darkblue" to "linkcolor" (default
  3423 value unchanged, can be redefined via \definecolor); no longer sets
  3424 "a4paper" option (unnecessary or even intrusive).
  3425 
  3426 * Antiquotation @{lemma A method} proves proposition A by the given
  3427 method (either a method name or a method name plus (optional) method
  3428 arguments in parentheses) and prints A just like @{prop A}.
  3429 
  3430 
  3431 *** HOL ***
  3432 
  3433 * New primrec package.  Specification syntax conforms in style to
  3434 definition/function/....  No separate induction rule is provided.  The
  3435 "primrec" command distinguishes old-style and new-style specifications
  3436 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3437 When adjusting theories, beware: constants stemming from new-style
  3438 primrec specifications have authentic syntax.
  3439 
  3440 * Metis prover is now an order of magnitude faster, and also works
  3441 with multithreading.
  3442 
  3443 * Metis: the maximum number of clauses that can be produced from a
  3444 theorem is now given by the attribute max_clauses.  Theorems that
  3445 exceed this number are ignored, with a warning printed.
  3446 
  3447 * Sledgehammer no longer produces structured proofs by default. To
  3448 enable, declare [[sledgehammer_full = true]].  Attributes
  3449 reconstruction_modulus, reconstruction_sorts renamed
  3450 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3451 
  3452 * Method "induct_scheme" derives user-specified induction rules
  3453 from well-founded induction and completeness of patterns. This factors
  3454 out some operations that are done internally by the function package
  3455 and makes them available separately.  See
  3456 src/HOL/ex/Induction_Scheme.thy for examples.
  3457 
  3458 * More flexible generation of measure functions for termination
  3459 proofs: Measure functions can be declared by proving a rule of the
  3460 form "is_measure f" and giving it the [measure_function] attribute.
  3461 The "is_measure" predicate is logically meaningless (always true), and
  3462 just guides the heuristic.  To find suitable measure functions, the
  3463 termination prover sets up the goal "is_measure ?f" of the appropriate
  3464 type and generates all solutions by prolog-style backwards proof using
  3465 the declared rules.
  3466 
  3467 This setup also deals with rules like 
  3468 
  3469   "is_measure f ==> is_measure (list_size f)"
  3470 
  3471 which accommodates nested datatypes that recurse through lists.
  3472 Similar rules are predeclared for products and option types.
  3473 
  3474 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3475 
  3476   INCOMPATIBILITIES:
  3477 
  3478   - Definitions of overloaded constants on sets have to be replaced by
  3479     definitions on => and bool.
  3480 
  3481   - Some definitions of overloaded operators on sets can now be proved
  3482     using the definitions of the operators on => and bool.  Therefore,
  3483     the following theorems have been renamed:
  3484 
  3485       subset_def   -> subset_eq
  3486       psubset_def  -> psubset_eq
  3487       set_diff_def -> set_diff_eq
  3488       Compl_def    -> Compl_eq
  3489       Sup_set_def  -> Sup_set_eq
  3490       Inf_set_def  -> Inf_set_eq
  3491       sup_set_def  -> sup_set_eq
  3492       inf_set_def  -> inf_set_eq
  3493 
  3494   - Due to the incompleteness of the HO unification algorithm, some
  3495     rules such as subst may require manual instantiation, if some of
  3496     the unknowns in the rule is a set.
  3497 
  3498   - Higher order unification and forward proofs:
  3499     The proof pattern
  3500 
  3501       have "P (S::'a set)" <...>
  3502       then have "EX S. P S" ..
  3503 
  3504     no longer works (due to the incompleteness of the HO unification
  3505     algorithm) and must be replaced by the pattern
  3506 
  3507       have "EX S. P S"
  3508       proof
  3509         show "P S" <...>
  3510       qed
  3511 
  3512   - Calculational reasoning with subst (or similar rules):
  3513     The proof pattern
  3514 
  3515       have "P (S::'a set)" <...>
  3516       also have "S = T" <...>
  3517       finally have "P T" .
  3518 
  3519     no longer works (for similar reasons as the previous example) and
  3520     must be replaced by something like
  3521 
  3522       have "P (S::'a set)" <...>
  3523       moreover have "S = T" <...>
  3524       ultimately have "P T" by simp
  3525 
  3526   - Tactics or packages written in ML code:
  3527     Code performing pattern matching on types via
  3528 
  3529       Type ("set", [T]) => ...
  3530 
  3531     must be rewritten. Moreover, functions like strip_type or
  3532     binder_types no longer return the right value when applied to a
  3533     type of the form
  3534 
  3535       T1 => ... => Tn => U => bool
  3536 
  3537     rather than
  3538 
  3539       T1 => ... => Tn => U set
  3540 
  3541 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3542 Wellfounded_Relations to theory Wellfounded.
  3543 
  3544 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3545 
  3546 * Class finite no longer treats UNIV as class parameter.  Use class
  3547 enum from theory Library/Enum instead to achieve a similar effect.
  3548 INCOMPATIBILITY.
  3549 
  3550 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3551 and "Cons".  INCOMPATIBILITY.
  3552 
  3553 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3554 Potential INCOMPATIBILITY.
  3555 
  3556 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3557 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3558 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3559 
  3560 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3561 the same name in theory Orderings:
  3562 
  3563   less_trans
  3564   less_linear
  3565   le_imp_less_or_eq
  3566   le_less_trans
  3567   less_le_trans
  3568   less_not_sym
  3569   less_asym
  3570 
  3571 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3572 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3573 and different variable names.
  3574 
  3575 * Library/Option_ord.thy: Canonical order on option type.
  3576 
  3577 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3578 finite maps.
  3579 
  3580 * Library/Countable.thy: Type class for countable types.
  3581 
  3582 * Theory Int: The representation of numerals has changed.  The infix
  3583 operator BIT and the bit datatype with constructors B0 and B1 have
  3584 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3585 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3586 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3587 accordingly.
  3588 
  3589 * Theory Nat: definition of <= and < on natural numbers no longer
  3590 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3591 le_def and less_def have disappeared.  Consider lemmas not_less
  3592 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3593 
  3594 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3595 (whose purpose mainly is for various fold_set functionals) have been
  3596 abandoned in favor of the existing algebraic classes
  3597 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3598 lower_semilattice (resp. upper_semilattice) and linorder.
  3599 INCOMPATIBILITY.
  3600 
  3601 * Theory Transitive_Closure: induct and cases rules now declare proper
  3602 case_names ("base" and "step").  INCOMPATIBILITY.
  3603 
  3604 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3605 lattices.  The form set-specific version is available as
  3606 Inductive.lfp_ordinal_induct_set.
  3607 
  3608 * Renamed theorems "power.simps" to "power_int.simps".
  3609 INCOMPATIBILITY.
  3610 
  3611 * Class semiring_div provides basic abstract properties of semirings
  3612 with division and modulo operations.  Subsumes former class dvd_mod.
  3613 
  3614 * Merged theories IntDef, Numeral and IntArith into unified theory
  3615 Int.  INCOMPATIBILITY.
  3616 
  3617 * Theory Library/Code_Index: type "index" now represents natural
  3618 numbers rather than integers.  INCOMPATIBILITY.
  3619 
  3620 * New class "uminus" with operation "uminus" (split of from class
  3621 "minus" which now only has operation "minus", binary).
  3622 INCOMPATIBILITY.
  3623 
  3624 * Constants "card", "internal_split", "option_map" now with authentic
  3625 syntax.  INCOMPATIBILITY.
  3626 
  3627 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3628 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3629 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3630 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3631 Sup_set_def, le_def, less_def, option_map_def now with object
  3632 equality.  INCOMPATIBILITY.
  3633 
  3634 * Records. Removed K_record, and replaced it by pure lambda term
  3635 %x. c. The simplifier setup is now more robust against eta expansion.
  3636 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3637 
  3638 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3639 
  3640 * Library/ListVector: new theory of arithmetic vector operations.
  3641 
  3642 * Library/Order_Relation: new theory of various orderings as sets of
  3643 pairs.  Defines preorders, partial orders, linear orders and
  3644 well-orders on sets and on types.
  3645 
  3646 
  3647 *** ZF ***
  3648 
  3649 * Renamed some theories to allow to loading both ZF and HOL in the
  3650 same session:
  3651 
  3652   Datatype  -> Datatype_ZF
  3653   Inductive -> Inductive_ZF
  3654   Int       -> Int_ZF
  3655   IntDiv    -> IntDiv_ZF
  3656   Nat       -> Nat_ZF
  3657   List      -> List_ZF
  3658   Main      -> Main_ZF
  3659 
  3660 INCOMPATIBILITY: ZF theories that import individual theories below
  3661 Main might need to be adapted.  Regular theory Main is still
  3662 available, as trivial extension of Main_ZF.
  3663 
  3664 
  3665 *** ML ***
  3666 
  3667 * ML within Isar: antiquotation @{const name} or @{const
  3668 name(typargs)} produces statically-checked Const term.
  3669 
  3670 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3671 (of the same name).  Removed obsolete print command.
  3672 
  3673 * Removed obsolete "use_legacy_bindings" function.
  3674 
  3675 * The ``print mode'' is now a thread-local value derived from a global
  3676 template (the former print_mode reference), thus access becomes
  3677 non-critical.  The global print_mode reference is for session
  3678 management only; user-code should use print_mode_value,
  3679 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3680 
  3681 * Functions system/system_out provide a robust way to invoke external
  3682 shell commands, with propagation of interrupts (requires Poly/ML
  3683 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3684 
  3685 
  3686 *** System ***
  3687 
  3688 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3689 in accordance with Proof General 3.7, which prefers GNU emacs.
  3690 
  3691 * isatool tty runs Isabelle process with plain tty interaction;
  3692 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3693 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3694 
  3695 * isatool browser now works with Cygwin as well, using general
  3696 "javapath" function defined in Isabelle process environment.
  3697 
  3698 * YXML notation provides a simple and efficient alternative to
  3699 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3700 isatool yxml as described in the Isabelle system manual.
  3701 
  3702 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3703 provides general wrapper for managing an Isabelle process in a robust
  3704 fashion, with ``cooked'' output from stdin/stderr.
  3705 
  3706 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3707 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3708 
  3709 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3710 way of changing the user's settings is via
  3711 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3712 script.
  3713 
  3714 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3715 cores of the underlying machine, which is a good starting point for
  3716 optimal performance tuning.  The corresponding usedir option -M allows
  3717 "max" as an alias for "0".  WARNING: does not work on certain versions
  3718 of Mac OS (with Poly/ML 5.1).
  3719 
  3720 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3721 adverse effect of Isabelle flooding interactive front-ends (notably
  3722 ProofGeneral / XEmacs).
  3723 
  3724 
  3725 
  3726 New in Isabelle2007 (November 2007)
  3727 -----------------------------------
  3728 
  3729 *** General ***
  3730 
  3731 * More uniform information about legacy features, notably a
  3732 warning/error of "Legacy feature: ...", depending on the state of the
  3733 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3734 legacy features will disappear eventually.
  3735 
  3736 * Theory syntax: the header format ``theory A = B + C:'' has been
  3737 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3738 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3739 
  3740 * Theory syntax: the old non-Isar theory file format has been
  3741 discontinued altogether.  Note that ML proof scripts may still be used
  3742 with Isar theories; migration is usually quite simple with the ML
  3743 function use_legacy_bindings.  INCOMPATIBILITY.
  3744 
  3745 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3746 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3747 quotes.
  3748 
  3749 * Theory loader: be more serious about observing the static theory
  3750 header specifications (including optional directories), but not the
  3751 accidental file locations of previously successful loads.  The strict
  3752 update policy of former update_thy is now already performed by
  3753 use_thy, so the former has been removed; use_thys updates several
  3754 theories simultaneously, just as 'imports' within a theory header
  3755 specification, but without merging the results.  Potential
  3756 INCOMPATIBILITY: may need to refine theory headers and commands
  3757 ROOT.ML which depend on load order.
  3758 
  3759 * Theory loader: optional support for content-based file
  3760 identification, instead of the traditional scheme of full physical
  3761 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3762 (cf. the system manual).  The new scheme allows to work with
  3763 non-finished theories in persistent session images, such that source
  3764 files may be moved later on without requiring reloads.
  3765 
  3766 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3767 file (with the same base name as the theory) are considered a legacy
  3768 feature, which will disappear eventually. Even now, the theory loader
  3769 no longer maintains dependencies on such files.
  3770 
  3771 * Syntax: the scope for resolving ambiguities via type-inference is
  3772 now limited to individual terms, instead of whole simultaneous
  3773 specifications as before. This greatly reduces the complexity of the
  3774 syntax module and improves flexibility by separating parsing and
  3775 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3776 'fixes' etc.) are required in rare situations.
  3777 
  3778 * Syntax: constants introduced by new-style packages ('definition',
  3779 'abbreviation' etc.) are passed through the syntax module in
  3780 ``authentic mode''. This means that associated mixfix annotations
  3781 really stick to such constants, independently of potential name space
  3782 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3783 trees are represented slightly differently, may need to adapt syntax
  3784 translations accordingly. Use CONST marker in 'translations' and
  3785 @{const_syntax} antiquotation in 'parse_translation' etc.
  3786 
  3787 * Legacy goal package: reduced interface to the bare minimum required
  3788 to keep existing proof scripts running.  Most other user-level
  3789 functions are now part of the OldGoals structure, which is *not* open
  3790 by default (consider isatool expandshort before open OldGoals).
  3791 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3792 these tend to cause confusion about the actual goal (!) context being
  3793 used here, which is not necessarily the same as the_context().
  3794 
  3795 * Command 'find_theorems': supports "*" wild-card in "name:"
  3796 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3797 support a specific search form (see ProofGeneral/CHANGES).
  3798 
  3799 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3800 by default, which means that "prems" (and also "fixed variables") are
  3801 suppressed from proof state output.  Note that the ProofGeneral
  3802 settings mechanism allows to change and save options persistently, but
  3803 older versions of Isabelle will fail to start up if a negative prems
  3804 limit is imposed.
  3805 
  3806 * Local theory targets may be specified by non-nested blocks of
  3807 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3808 contain definitions, theorems etc., including any derived mechanism
  3809 that has been implemented on top of these primitives.  This concept
  3810 generalizes the existing ``theorem (in ...)'' towards more versatility
  3811 and scalability.
  3812 
  3813 * Proof General interface: proper undo of final 'end' command;
  3814 discontinued Isabelle/classic mode (ML proof scripts).
  3815 
  3816 
  3817 *** Document preparation ***
  3818 
  3819 * Added antiquotation @{theory name} which prints the given name,
  3820 after checking that it refers to a valid ancestor theory in the
  3821 current context.
  3822 
  3823 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3824 check the given source text as ML type/structure, printing verbatim.
  3825 
  3826 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3827 "c args == rhs" given in the current context.  (Any number of
  3828 arguments may be given on the LHS.)
  3829 
  3830 
  3831 *** Pure ***
  3832 
  3833 * The 'class' package offers a combination of axclass and locale to
  3834 achieve Haskell-like type classes in Isabelle.  Definitions and
  3835 theorems within a class context produce both relative results (with
  3836 implicit parameters according to the locale context), and polymorphic
  3837 constants with qualified polymorphism (according to the class
  3838 context).  Within the body context of a 'class' target, a separate
  3839 syntax layer ("user space type system") takes care of converting
  3840 between global polymorphic consts and internal locale representation.
  3841 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3842 "isatool doc classes" provides a tutorial.
  3843 
  3844 * Generic code generator framework allows to generate executable
  3845 code for ML and Haskell (including Isabelle classes).  A short usage
  3846 sketch:
  3847 
  3848     internal compilation:
  3849         export_code <list of constants (term syntax)> in SML
  3850     writing SML code to a file:
  3851         export_code <list of constants (term syntax)> in SML <filename>
  3852     writing OCaml code to a file:
  3853         export_code <list of constants (term syntax)> in OCaml <filename>
  3854     writing Haskell code to a bunch of files:
  3855         export_code <list of constants (term syntax)> in Haskell <filename>
  3856 
  3857     evaluating closed propositions to True/False using code generation:
  3858         method ``eval''
  3859 
  3860 Reasonable default setup of framework in HOL.
  3861 
  3862 Theorem attributs for selecting and transforming function equations theorems:
  3863 
  3864     [code fun]:        select a theorem as function equation for a specific constant
  3865     [code fun del]:    deselect a theorem as function equation for a specific constant
  3866     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3867     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3868 
  3869 User-defined serializations (target in {SML, OCaml, Haskell}):
  3870 
  3871     code_const <and-list of constants (term syntax)>
  3872       {(target) <and-list of const target syntax>}+
  3873 
  3874     code_type <and-list of type constructors>
  3875       {(target) <and-list of type target syntax>}+
  3876 
  3877     code_instance <and-list of instances>
  3878       {(target)}+
  3879         where instance ::= <type constructor> :: <class>
  3880 
  3881     code_class <and_list of classes>
  3882       {(target) <and-list of class target syntax>}+
  3883         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3884 
  3885 code_instance and code_class only are effective to target Haskell.
  3886 
  3887 For example usage see src/HOL/ex/Codegenerator.thy and
  3888 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3889 generation from Isabelle/HOL theories is available via "isatool doc
  3890 codegen".
  3891 
  3892 * Code generator: consts in 'consts_code' Isar commands are now
  3893 referred to by usual term syntax (including optional type
  3894 annotations).
  3895 
  3896 * Command 'no_translations' removes translation rules from theory
  3897 syntax.
  3898 
  3899 * Overloaded definitions are now actually checked for acyclic
  3900 dependencies.  The overloading scheme is slightly more general than
  3901 that of Haskell98, although Isabelle does not demand an exact
  3902 correspondence to type class and instance declarations.
  3903 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3904 exotic versions of overloading -- at the discretion of the user!
  3905 
  3906 Polymorphic constants are represented via type arguments, i.e. the
  3907 instantiation that matches an instance against the most general
  3908 declaration given in the signature.  For example, with the declaration
  3909 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3910 as c(nat).  Overloading is essentially simultaneous structural
  3911 recursion over such type arguments.  Incomplete specification patterns
  3912 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3913 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3914 Command 'print_theory' outputs the normalized system of recursive
  3915 equations, see section "definitions".
  3916 
  3917 * Configuration options are maintained within the theory or proof
  3918 context (with name and type bool/int/string), providing a very simple
  3919 interface to a poor-man's version of general context data.  Tools may
  3920 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3921 these values using Config.get etc.  Users may change options via an
  3922 associated attribute of the same name.  This form of context
  3923 declaration works particularly well with commands 'declare' or
  3924 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3925 very easy to avoid global references, which would not observe Isar
  3926 toplevel undo/redo and fail to work with multithreading.
  3927 
  3928 Various global ML references of Pure and HOL have been turned into
  3929 configuration options:
  3930 
  3931   Unify.search_bound		unify_search_bound
  3932   Unify.trace_bound		unify_trace_bound
  3933   Unify.trace_simp		unify_trace_simp
  3934   Unify.trace_types		unify_trace_types
  3935   Simplifier.simp_depth_limit	simp_depth_limit
  3936   Blast.depth_limit		blast_depth_limit
  3937   DatatypeProp.dtK		datatype_distinctness_limit
  3938   fast_arith_neq_limit  	fast_arith_neq_limit
  3939   fast_arith_split_limit	fast_arith_split_limit
  3940 
  3941 * Named collections of theorems may be easily installed as context
  3942 data using the functor NamedThmsFun (see also
  3943 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3944 attributes; there is also a toplevel print command.  This facility is
  3945 just a common case of general context data, which is the preferred way
  3946 for anything more complex than just a list of facts in canonical
  3947 order.
  3948 
  3949 * Isar: command 'declaration' augments a local theory by generic
  3950 declaration functions written in ML.  This enables arbitrary content
  3951 being added to the context, depending on a morphism that tells the
  3952 difference of the original declaration context wrt. the application
  3953 context encountered later on.
  3954 
  3955 * Isar: proper interfaces for simplification procedures.  Command
  3956 'simproc_setup' declares named simprocs (with match patterns, and body
  3957 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3958 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3959 
  3960 * Isar: an extra pair of brackets around attribute declarations
  3961 abbreviates a theorem reference involving an internal dummy fact,
  3962 which will be ignored later --- only the effect of the attribute on
  3963 the background context will persist.  This form of in-place
  3964 declarations is particularly useful with commands like 'declare' and
  3965 'using', for example ``have A using [[simproc a]] by simp''.
  3966 
  3967 * Isar: method "assumption" (and implicit closing of subproofs) now
  3968 takes simple non-atomic goal assumptions into account: after applying
  3969 an assumption as a rule the resulting subgoals are solved by atomic
  3970 assumption steps.  This is particularly useful to finish 'obtain'
  3971 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3972 without referring to the original premise "!!x. P x ==> thesis" in the
  3973 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3974 more permissive.
  3975 
  3976 * Isar: implicit use of prems from the Isar proof context is
  3977 considered a legacy feature.  Common applications like ``have A .''
  3978 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3979 referencing facts explicitly here improves readability and
  3980 maintainability of proof texts.
  3981 
  3982 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3983 the obtained context from the course of reasoning!  For example:
  3984 
  3985   assume "EX x y. A x & B y"   -- "any previous fact"
  3986   then guess x and y by clarify
  3987 
  3988 This technique is potentially adventurous, depending on the facts and
  3989 proof tools being involved here.
  3990 
  3991 * Isar: known facts from the proof context may be specified as literal
  3992 propositions, using ASCII back-quote syntax.  This works wherever
  3993 named facts used to be allowed so far, in proof commands, proof
  3994 methods, attributes etc.  Literal facts are retrieved from the context
  3995 according to unification of type and term parameters.  For example,
  3996 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3997 theorems in the current context, then these are valid literal facts:
  3998 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3999 
  4000 There is also a proof method "fact" which does the same composition
  4001 for explicit goal states, e.g. the following proof texts coincide with
  4002 certain special cases of literal facts:
  4003 
  4004   have "A" by fact                 ==  note `A`
  4005   have "A ==> B" by fact           ==  note `A ==> B`
  4006   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  4007   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  4008 
  4009 * Isar: ":" (colon) is no longer a symbolic identifier character in
  4010 outer syntax.  Thus symbolic identifiers may be used without
  4011 additional white space in declarations like this: ``assume *: A''.
  4012 
  4013 * Isar: 'print_facts' prints all local facts of the current context,
  4014 both named and unnamed ones.
  4015 
  4016 * Isar: 'def' now admits simultaneous definitions, e.g.:
  4017 
  4018   def x == "t" and y == "u"
  4019 
  4020 * Isar: added command 'unfolding', which is structurally similar to
  4021 'using', but affects both the goal state and facts by unfolding given
  4022 rewrite rules.  Thus many occurrences of the 'unfold' method or
  4023 'unfolded' attribute may be replaced by first-class proof text.
  4024 
  4025 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  4026 and command 'unfolding' now all support object-level equalities
  4027 (potentially conditional).  The underlying notion of rewrite rule is
  4028 analogous to the 'rule_format' attribute, but *not* that of the
  4029 Simplifier (which is usually more generous).
  4030 
  4031 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  4032 premises of a theorem by n. Useful in conjunction with drule.
  4033 
  4034 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  4035 method expression within a sandbox consisting of the first N
  4036 sub-goals, which need to exist.  For example, ``simp_all [3]''
  4037 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  4038 simplifies all new goals that emerge from applying rule foo to the
  4039 originally first one.
  4040 
  4041 * Isar: schematic goals are no longer restricted to higher-order
  4042 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  4043 expected.
  4044 
  4045 * Isar: the conclusion of a long theorem statement is now either
  4046 'shows' (a simultaneous conjunction, as before), or 'obtains'
  4047 (essentially a disjunction of cases with local parameters and
  4048 assumptions).  The latter allows to express general elimination rules
  4049 adequately; in this notation common elimination rules look like this:
  4050 
  4051   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  4052     assumes "EX x. P x"
  4053     obtains x where "P x"
  4054 
  4055   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  4056     assumes "A & B"
  4057     obtains A and B
  4058 
  4059   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  4060     assumes "A | B"
  4061     obtains
  4062       A
  4063     | B
  4064 
  4065 The subsequent classical rules even refer to the formal "thesis"
  4066 explicitly:
  4067 
  4068   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  4069     obtains "~ thesis"
  4070 
  4071   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  4072     obtains "thesis ==> something"
  4073 
  4074 The actual proof of an 'obtains' statement is analogous to that of the
  4075 Isar proof element 'obtain', only that there may be several cases.
  4076 Optional case names may be specified in parentheses; these will be
  4077 available both in the present proof and as annotations in the
  4078 resulting rule, for later use with the 'cases' method (cf. attribute
  4079 case_names).
  4080 
  4081 * Isar: the assumptions of a long theorem statement are available as
  4082 "assms" fact in the proof context.  This is more appropriate than the
  4083 (historical) "prems", which refers to all assumptions of the current
  4084 context, including those from the target locale, proof body etc.
  4085 
  4086 * Isar: 'print_statement' prints theorems from the current theory or
  4087 proof context in long statement form, according to the syntax of a
  4088 top-level lemma.
  4089 
  4090 * Isar: 'obtain' takes an optional case name for the local context
  4091 introduction rule (default "that").
  4092 
  4093 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  4094 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  4095 to occur.
  4096 
  4097 * Pure: syntax "CONST name" produces a fully internalized constant
  4098 according to the current context.  This is particularly useful for
  4099 syntax translations that should refer to internal constant
  4100 representations independently of name spaces.
  4101 
  4102 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  4103 instead of "FOO ". This allows multiple binder declarations to coexist
  4104 in the same context.  INCOMPATIBILITY.
  4105 
  4106 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  4107 primitive that also works in a locale context (both for constants and
  4108 fixed variables). Type declaration and internal syntactic representation
  4109 of given constants retrieved from the context. Likewise, the
  4110 'no_notation' command allows to remove given syntax annotations from the
  4111 current context.
  4112 
  4113 * Isar/locales: new derived specification elements 'axiomatization',
  4114 'definition', 'abbreviation', which support type-inference, admit
  4115 object-level specifications (equality, equivalence).  See also the
  4116 isar-ref manual.  Examples:
  4117 
  4118   axiomatization
  4119     eq  (infix "===" 50) where
  4120     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  4121 
  4122   definition "f x y = x + y + 1"
  4123   definition g where "g x = f x x"
  4124 
  4125   abbreviation
  4126     neq  (infix "=!=" 50) where
  4127     "x =!= y == ~ (x === y)"
  4128 
  4129 These specifications may be also used in a locale context.  Then the
  4130 constants being introduced depend on certain fixed parameters, and the
  4131 constant name is qualified by the locale base name.  An internal
  4132 abbreviation takes care for convenient input and output, making the
  4133 parameters implicit and using the original short name.  See also
  4134 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  4135 entities from a monomorphic theory.
  4136 
  4137 Presently, abbreviations are only available 'in' a target locale, but
  4138 not inherited by general import expressions.  Also note that
  4139 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  4140 'translations' in common applications.  The "no_abbrevs" print mode
  4141 prevents folding of abbreviations in term output.
  4142 
  4143 Concrete syntax is attached to specified constants in internal form,
  4144 independently of name spaces.  The parse tree representation is
  4145 slightly different -- use 'notation' instead of raw 'syntax', and
  4146 'translations' with explicit "CONST" markup to accommodate this.
  4147 
  4148 * Pure/Isar: unified syntax for new-style specification mechanisms
  4149 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  4150 full type inference and dummy patterns ("_").  For example:
  4151 
  4152   definition "K x _ = x"
  4153 
  4154   inductive conj for A B
  4155   where "A ==> B ==> conj A B"
  4156 
  4157 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  4158 the current context.  Print mode "no_abbrevs" prevents inversion of
  4159 abbreviations on output.
  4160 
  4161 * Isar/locales: improved parameter handling: use of locales "var" and
  4162 "struct" no longer necessary; - parameter renamings are no longer
  4163 required to be injective.  For example, this allows to define
  4164 endomorphisms as locale endom = homom mult mult h.
  4165 
  4166 * Isar/locales: changed the way locales with predicates are defined.
  4167 Instead of accumulating the specification, the imported expression is
  4168 now an interpretation.  INCOMPATIBILITY: different normal form of
  4169 locale expressions.  In particular, in interpretations of locales with
  4170 predicates, goals repesenting already interpreted fragments are not
  4171 removed automatically.  Use methods `intro_locales' and
  4172 `unfold_locales'; see below.
  4173 
  4174 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  4175 provide backward reasoning on locales predicates.  The methods are
  4176 aware of interpretations and discharge corresponding goals.
  4177 `intro_locales' is less aggressive then `unfold_locales' and does not
  4178 unfold predicates to assumptions.
  4179 
  4180 * Isar/locales: the order in which locale fragments are accumulated
  4181 has changed.  This enables to override declarations from fragments due
  4182 to interpretations -- for example, unwanted simp rules.
  4183 
  4184 * Isar/locales: interpretation in theories and proof contexts has been
  4185 extended.  One may now specify (and prove) equations, which are
  4186 unfolded in interpreted theorems.  This is useful for replacing
  4187 defined concepts (constants depending on locale parameters) by
  4188 concepts already existing in the target context.  Example:
  4189 
  4190   interpretation partial_order ["op <= :: [int, int] => bool"]
  4191     where "partial_order.less (op <=) (x::int) y = (x < y)"
  4192 
  4193 Typically, the constant `partial_order.less' is created by a
  4194 definition specification element in the context of locale
  4195 partial_order.
  4196 
  4197 * Method "induct": improved internal context management to support
  4198 local fixes and defines on-the-fly. Thus explicit meta-level
  4199 connectives !!  and ==> are rarely required anymore in inductive goals
  4200 (using object-logic connectives for this purpose has been long
  4201 obsolete anyway). Common proof patterns are explained in
  4202 src/HOL/Induct/Common_Patterns.thy, see also
  4203 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  4204 examples.
  4205 
  4206 * Method "induct": improved handling of simultaneous goals. Instead of
  4207 introducing object-level conjunction, the statement is now split into
  4208 several conclusions, while the corresponding symbolic cases are nested
  4209 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  4210 see src/HOL/Induct/Common_Patterns.thy, for example.
  4211 
  4212 * Method "induct": mutual induction rules are now specified as a list
  4213 of rule sharing the same induction cases. HOL packages usually provide
  4214 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  4215 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  4216 mutual induction rules differently, i.e. like this:
  4217 
  4218   (induct rule: foo_bar.inducts)
  4219   (induct set: foo bar)
  4220   (induct pred: foo bar)
  4221   (induct type: foo bar)
  4222 
  4223 The ML function ProjectRule.projections turns old-style rules into the
  4224 new format.
  4225 
  4226 * Method "coinduct": dual of induction, see
  4227 src/HOL/Library/Coinductive_List.thy for various examples.
  4228 
  4229 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  4230 considered a legacy feature.
  4231 
  4232 * Attribute "symmetric" produces result with standardized schematic
  4233 variables (index 0).  Potential INCOMPATIBILITY.
  4234 
  4235 * Simplifier: by default the simplifier trace only shows top level
  4236 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4237 default. Thus there is less danger of being flooded by the trace. The
  4238 trace indicates where parts have been suppressed.
  4239   
  4240 * Provers/classical: removed obsolete classical version of elim_format
  4241 attribute; classical elim/dest rules are now treated uniformly when
  4242 manipulating the claset.
  4243 
  4244 * Provers/classical: stricter checks to ensure that supplied intro,
  4245 dest and elim rules are well-formed; dest and elim rules must have at
  4246 least one premise.
  4247 
  4248 * Provers/classical: attributes dest/elim/intro take an optional
  4249 weight argument for the rule (just as the Pure versions).  Weights are
  4250 ignored by automated tools, but determine the search order of single
  4251 rule steps.
  4252 
  4253 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4254 where the body does not mention the bound variable.  Note that dummy
  4255 patterns implicitly depend on their context of bounds, which makes
  4256 "{_. _}" match any set comprehension as expected.  Potential
  4257 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4258 constant "_idtdummy" in the binding position.
  4259 
  4260 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4261 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4262 for example "A -> B" => "Pi A (%_. B)".
  4263 
  4264 * Pure: 'class_deps' command visualizes the subclass relation, using
  4265 the graph browser tool.
  4266 
  4267 * Pure: 'print_theory' now suppresses certain internal declarations by
  4268 default; use '!' option for full details.
  4269 
  4270 
  4271 *** HOL ***
  4272 
  4273 * Method "metis" proves goals by applying the Metis general-purpose
  4274 resolution prover (see also http://gilith.com/software/metis/).
  4275 Examples are in the directory MetisExamples.  WARNING: the
  4276 Isabelle/HOL-Metis integration does not yet work properly with
  4277 multi-threading.
  4278   
  4279 * Command 'sledgehammer' invokes external automatic theorem provers as
  4280 background processes.  It generates calls to the "metis" method if
  4281 successful. These can be pasted into the proof.  Users do not have to
  4282 wait for the automatic provers to return.  WARNING: does not really
  4283 work with multi-threading.
  4284 
  4285 * New "auto_quickcheck" feature tests outermost goal statements for
  4286 potential counter-examples.  Controlled by ML references
  4287 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4288 5000 milliseconds).  Fails silently if statements is outside of
  4289 executable fragment, or any other codgenerator problem occurs.
  4290 
  4291 * New constant "undefined" with axiom "undefined x = undefined".
  4292 
  4293 * Added class "HOL.eq", allowing for code generation with polymorphic
  4294 equality.
  4295 
  4296 * Some renaming of class constants due to canonical name prefixing in
  4297 the new 'class' package:
  4298 
  4299     HOL.abs ~> HOL.abs_class.abs
  4300     HOL.divide ~> HOL.divide_class.divide
  4301     0 ~> HOL.zero_class.zero
  4302     1 ~> HOL.one_class.one
  4303     op + ~> HOL.plus_class.plus
  4304     op - ~> HOL.minus_class.minus
  4305     uminus ~> HOL.minus_class.uminus
  4306     op * ~> HOL.times_class.times
  4307     op < ~> HOL.ord_class.less
  4308     op <= > HOL.ord_class.less_eq
  4309     Nat.power ~> Power.power_class.power
  4310     Nat.size ~> Nat.size_class.size
  4311     Numeral.number_of ~> Numeral.number_class.number_of
  4312     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4313     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4314     Orderings.min ~> Orderings.ord_class.min
  4315     Orderings.max ~> Orderings.ord_class.max
  4316     Divides.op div ~> Divides.div_class.div
  4317     Divides.op mod ~> Divides.div_class.mod
  4318     Divides.op dvd ~> Divides.div_class.dvd
  4319 
  4320 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4321 
  4322 a) User-defined constants using any of the names "plus", "minus",
  4323 "times", "less" or "less_eq". The standard syntax translations for
  4324 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4325 names.
  4326 
  4327 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4328 INCOMPATIBILITY: use more specific names.
  4329 
  4330 c) Permutative equations (e.g. "a + b = b + a")
  4331 Since the change of names also changes the order of terms, permutative
  4332 rewrite rules may get applied in a different order. Experience shows
  4333 that this is rarely the case (only two adaptions in the whole Isabelle
  4334 distribution).  INCOMPATIBILITY: rewrite proofs
  4335 
  4336 d) ML code directly refering to constant names
  4337 This in general only affects hand-written proof tactics, simprocs and
  4338 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4339 Consider using @{const_name} antiquotation.
  4340 
  4341 * New class "default" with associated constant "default".
  4342 
  4343 * Function "sgn" is now overloaded and available on int, real, complex
  4344 (and other numeric types), using class "sgn".  Two possible defs of
  4345 sgn are given as equational assumptions in the classes sgn_if and
  4346 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4347 INCOMPATIBILITY.
  4348 
  4349 * Locale "partial_order" now unified with class "order" (cf. theory
  4350 Orderings), added parameter "less".  INCOMPATIBILITY.
  4351 
  4352 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4353 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4354 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4355 
  4356 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4357 changed order of proof goals in instance proofs.
  4358 
  4359 * The transitivity reasoner for partial and linear orders is set up
  4360 for classes "order" and "linorder".  Instances of the reasoner are available
  4361 in all contexts importing or interpreting the corresponding locales.
  4362 Method "order" invokes the reasoner separately; the reasoner
  4363 is also integrated with the Simplifier as a solver.  Diagnostic
  4364 command 'print_orders' shows the available instances of the reasoner
  4365 in the current context.
  4366 
  4367 * Localized monotonicity predicate in theory "Orderings"; integrated
  4368 lemmas max_of_mono and min_of_mono with this predicate.
  4369 INCOMPATIBILITY.
  4370 
  4371 * Formulation of theorem "dense" changed slightly due to integration
  4372 with new class dense_linear_order.
  4373 
  4374 * Uniform lattice theory development in HOL.
  4375 
  4376     constants "meet" and "join" now named "inf" and "sup"
  4377     constant "Meet" now named "Inf"
  4378 
  4379     classes "meet_semilorder" and "join_semilorder" now named
  4380       "lower_semilattice" and "upper_semilattice"
  4381     class "lorder" now named "lattice"
  4382     class "comp_lat" now named "complete_lattice"
  4383 
  4384     Instantiation of lattice classes allows explicit definitions
  4385     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4386 
  4387   INCOMPATIBILITY.  Theorem renames:
  4388 
  4389     meet_left_le            ~> inf_le1
  4390     meet_right_le           ~> inf_le2
  4391     join_left_le            ~> sup_ge1
  4392     join_right_le           ~> sup_ge2
  4393     meet_join_le            ~> inf_sup_ord
  4394     le_meetI                ~> le_infI
  4395     join_leI                ~> le_supI
  4396     le_meet                 ~> le_inf_iff
  4397     le_join                 ~> ge_sup_conv
  4398     meet_idempotent         ~> inf_idem
  4399     join_idempotent         ~> sup_idem
  4400     meet_comm               ~> inf_commute
  4401     join_comm               ~> sup_commute
  4402     meet_leI1               ~> le_infI1
  4403     meet_leI2               ~> le_infI2
  4404     le_joinI1               ~> le_supI1
  4405     le_joinI2               ~> le_supI2
  4406     meet_assoc              ~> inf_assoc
  4407     join_assoc              ~> sup_assoc
  4408     meet_left_comm          ~> inf_left_commute
  4409     meet_left_idempotent    ~> inf_left_idem
  4410     join_left_comm          ~> sup_left_commute
  4411     join_left_idempotent    ~> sup_left_idem
  4412     meet_aci                ~> inf_aci
  4413     join_aci                ~> sup_aci
  4414     le_def_meet             ~> le_iff_inf
  4415     le_def_join             ~> le_iff_sup
  4416     join_absorp2            ~> sup_absorb2
  4417     join_absorp1            ~> sup_absorb1
  4418     meet_absorp1            ~> inf_absorb1
  4419     meet_absorp2            ~> inf_absorb2
  4420     meet_join_absorp        ~> inf_sup_absorb
  4421     join_meet_absorp        ~> sup_inf_absorb
  4422     distrib_join_le         ~> distrib_sup_le
  4423     distrib_meet_le         ~> distrib_inf_le
  4424 
  4425     add_meet_distrib_left   ~> add_inf_distrib_left
  4426     add_join_distrib_left   ~> add_sup_distrib_left
  4427     is_join_neg_meet        ~> is_join_neg_inf
  4428     is_meet_neg_join        ~> is_meet_neg_sup
  4429     add_meet_distrib_right  ~> add_inf_distrib_right
  4430     add_join_distrib_right  ~> add_sup_distrib_right
  4431     add_meet_join_distribs  ~> add_sup_inf_distribs
  4432     join_eq_neg_meet        ~> sup_eq_neg_inf
  4433     meet_eq_neg_join        ~> inf_eq_neg_sup
  4434     add_eq_meet_join        ~> add_eq_inf_sup
  4435     meet_0_imp_0            ~> inf_0_imp_0
  4436     join_0_imp_0            ~> sup_0_imp_0
  4437     meet_0_eq_0             ~> inf_0_eq_0
  4438     join_0_eq_0             ~> sup_0_eq_0
  4439     neg_meet_eq_join        ~> neg_inf_eq_sup
  4440     neg_join_eq_meet        ~> neg_sup_eq_inf
  4441     join_eq_if              ~> sup_eq_if
  4442 
  4443     mono_meet               ~> mono_inf
  4444     mono_join               ~> mono_sup
  4445     meet_bool_eq            ~> inf_bool_eq
  4446     join_bool_eq            ~> sup_bool_eq
  4447     meet_fun_eq             ~> inf_fun_eq
  4448     join_fun_eq             ~> sup_fun_eq
  4449     meet_set_eq             ~> inf_set_eq
  4450     join_set_eq             ~> sup_set_eq
  4451     meet1_iff               ~> inf1_iff
  4452     meet2_iff               ~> inf2_iff
  4453     meet1I                  ~> inf1I
  4454     meet2I                  ~> inf2I
  4455     meet1D1                 ~> inf1D1
  4456     meet2D1                 ~> inf2D1
  4457     meet1D2                 ~> inf1D2
  4458     meet2D2                 ~> inf2D2
  4459     meet1E                  ~> inf1E
  4460     meet2E                  ~> inf2E
  4461     join1_iff               ~> sup1_iff
  4462     join2_iff               ~> sup2_iff
  4463     join1I1                 ~> sup1I1
  4464     join2I1                 ~> sup2I1
  4465     join1I1                 ~> sup1I1
  4466     join2I2                 ~> sup1I2
  4467     join1CI                 ~> sup1CI
  4468     join2CI                 ~> sup2CI
  4469     join1E                  ~> sup1E
  4470     join2E                  ~> sup2E
  4471 
  4472     is_meet_Meet            ~> is_meet_Inf
  4473     Meet_bool_def           ~> Inf_bool_def
  4474     Meet_fun_def            ~> Inf_fun_def
  4475     Meet_greatest           ~> Inf_greatest
  4476     Meet_lower              ~> Inf_lower
  4477     Meet_set_def            ~> Inf_set_def
  4478 
  4479     Sup_def                 ~> Sup_Inf
  4480     Sup_bool_eq             ~> Sup_bool_def
  4481     Sup_fun_eq              ~> Sup_fun_def
  4482     Sup_set_eq              ~> Sup_set_def
  4483 
  4484     listsp_meetI            ~> listsp_infI
  4485     listsp_meet_eq          ~> listsp_inf_eq
  4486 
  4487     meet_min                ~> inf_min
  4488     join_max                ~> sup_max
  4489 
  4490 * Added syntactic class "size"; overloaded constant "size" now has
  4491 type "'a::size ==> bool"
  4492 
  4493 * Internal reorganisation of `size' of datatypes: size theorems
  4494 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4495 simplification rules by default!); theorems "prod.size" now named
  4496 "*.size".
  4497 
  4498 * Class "div" now inherits from class "times" rather than "type".
  4499 INCOMPATIBILITY.
  4500 
  4501 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4502 Linorder etc.  have disappeared; operations defined in terms of
  4503 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4504 
  4505 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4506 
  4507 * HOL-Word: New extensive library and type for generic, fixed size
  4508 machine words, with arithemtic, bit-wise, shifting and rotating
  4509 operations, reflection into int, nat, and bool lists, automation for
  4510 linear arithmetic (by automatic reflection into nat or int), including
  4511 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4512 arithmetic type classes, supporting automatic simplification of
  4513 numerals on all operations.
  4514 
  4515 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4516 
  4517 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4518 
  4519 * Code generator library theories:
  4520   - Code_Integer represents HOL integers by big integer literals in target
  4521     languages.
  4522   - Code_Char represents HOL characters by character literals in target
  4523     languages.
  4524   - Code_Char_chr like Code_Char, but also offers treatment of character
  4525     codes; includes Code_Integer.
  4526   - Executable_Set allows to generate code for finite sets using lists.
  4527   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4528     denominator).
  4529   - Executable_Real implements a subset of real numbers, namly those
  4530     representable by rational numbers.
  4531   - Efficient_Nat implements natural numbers by integers, which in general will
  4532     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4533     includes Code_Integer.
  4534   - Code_Index provides an additional datatype index which is mapped to
  4535     target-language built-in integers.
  4536   - Code_Message provides an additional datatype message_string which is isomorphic to
  4537     strings; messages are mapped to target-language strings.
  4538 
  4539 * New package for inductive predicates
  4540 
  4541   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4542 
  4543     inductive
  4544       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4545       for z_1 :: U_1 and ... and z_n :: U_m
  4546     where
  4547       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4548     | ...
  4549 
  4550   with full support for type-inference, rather than
  4551 
  4552     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4553 
  4554     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4555     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4556 
  4557     inductive "s z_1 ... z_m"
  4558     intros
  4559       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4560       ...
  4561 
  4562   For backward compatibility, there is a wrapper allowing inductive
  4563   sets to be defined with the new package via
  4564 
  4565     inductive_set
  4566       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4567       for z_1 :: U_1 and ... and z_n :: U_m
  4568     where
  4569       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4570     | ...
  4571 
  4572   or
  4573 
  4574     inductive_set
  4575       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4576       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4577       for z_1 :: U_1 and ... and z_n :: U_m
  4578     where
  4579       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4580     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4581     | ...
  4582 
  4583   if the additional syntax "p ..." is required.
  4584 
  4585   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4586   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4587 
  4588   INCOMPATIBILITIES:
  4589 
  4590   - Since declaration and definition of inductive sets or predicates
  4591     is no longer separated, abbreviations involving the newly
  4592     introduced sets or predicates must be specified together with the
  4593     introduction rules after the 'where' keyword (see above), rather
  4594     than before the actual inductive definition.
  4595 
  4596   - The variables in induction and elimination rules are now
  4597     quantified in the order of their occurrence in the introduction
  4598     rules, rather than in alphabetical order. Since this may break
  4599     some proofs, these proofs either have to be repaired, e.g. by
  4600     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4601     statements of the form
  4602 
  4603       case (rule_i a_i_1 ... a_i_{k_i})
  4604 
  4605     or the old order of quantification has to be restored by explicitly adding
  4606     meta-level quantifiers in the introduction rules, i.e.
  4607 
  4608       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4609 
  4610   - The format of the elimination rules is now
  4611 
  4612       p z_1 ... z_m x_1 ... x_n ==>
  4613         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4614         ==> ... ==> P
  4615 
  4616     for predicates and
  4617 
  4618       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4619         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4620         ==> ... ==> P
  4621 
  4622     for sets rather than
  4623 
  4624       x : s z_1 ... z_m ==>
  4625         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4626         ==> ... ==> P
  4627 
  4628     This may require terms in goals to be expanded to n-tuples
  4629     (e.g. using case_tac or simplification with the split_paired_all
  4630     rule) before the above elimination rule is applicable.
  4631 
  4632   - The elimination or case analysis rules for (mutually) inductive
  4633     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4634     list of rules "p_1_..._p_k.elims" is no longer available.
  4635 
  4636 * New package "function"/"fun" for general recursive functions,
  4637 supporting mutual and nested recursion, definitions in local contexts,
  4638 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4639 for small examples, and the separate tutorial on the function
  4640 package. The old recdef "package" is still available as before, but
  4641 users are encouraged to use the new package.
  4642 
  4643 * Method "lexicographic_order" automatically synthesizes termination
  4644 relations as lexicographic combinations of size measures. 
  4645 
  4646 * Case-expressions allow arbitrary constructor-patterns (including
  4647 "_") and take their order into account, like in functional
  4648 programming.  Internally, this is translated into nested
  4649 case-expressions; missing cases are added and mapped to the predefined
  4650 constant "undefined". In complicated cases printing may no longer show
  4651 the original input but the internal form. Lambda-abstractions allow
  4652 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4653 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4654 variable.
  4655 
  4656 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4657 is an abbreviation for "of_nat :: nat => int". The simplification
  4658 rules for "of_nat" have been changed to work like "int" did
  4659 previously.  Potential INCOMPATIBILITY:
  4660   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4661   - of_nat_diff and of_nat_mult are no longer default simp rules
  4662 
  4663 * Method "algebra" solves polynomial equations over (semi)rings using
  4664 Groebner bases. The (semi)ring structure is defined by locales and the
  4665 tool setup depends on that generic context. Installing the method for
  4666 a specific type involves instantiating the locale and possibly adding
  4667 declarations for computation on the coefficients.  The method is
  4668 already instantiated for natural numbers and for the axiomatic class
  4669 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4670 CALCULEMUS 2007 for the general principles underlying this
  4671 architecture of context-aware proof-tools.
  4672 
  4673 * Method "ferrack" implements quantifier elimination over
  4674 special-purpose dense linear orders using locales (analogous to
  4675 "algebra"). The method is already installed for class
  4676 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4677 rat, etc.
  4678 
  4679 * Former constant "List.op @" now named "List.append".  Use ML
  4680 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4681 circumvent possible incompatibilities when working on ML level.
  4682 
  4683 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4684 
  4685 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4686 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4687 
  4688 * New syntax for Haskell-like list comprehension (input only), eg.
  4689 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4690 
  4691 * The special syntax for function "filter" has changed from [x :
  4692 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4693 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4694 
  4695 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4696 defined on nat only, as an abbreviation for [a..<Suc b]
  4697 INCOMPATIBILITY.
  4698 
  4699 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4700 
  4701 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4702 
  4703 * New lemma collection field_simps (an extension of ring_simps) for
  4704 manipulating (in)equations involving division. Multiplies with all
  4705 denominators that can be proved to be non-zero (in equations) or
  4706 positive/negative (in inequations).
  4707 
  4708 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4709 have been improved and renamed to ring_simps, group_simps and
  4710 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4711 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4712 
  4713 * Theory Library/Commutative_Ring: switched from recdef to function
  4714 package; constants add, mul, pow now curried.  Infix syntax for
  4715 algebraic operations.
  4716 
  4717 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4718 INCOMPATIBILITY.
  4719 
  4720 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4721 INCOMPATIBILITY.
  4722 
  4723 * HOL/records: generalised field-update to take a function on the
  4724 field rather than the new value: r(|A := x|) is translated to A_update
  4725 (K x) r The K-combinator that is internally used is called K_record.
  4726 INCOMPATIBILITY: Usage of the plain update functions has to be
  4727 adapted.
  4728  
  4729 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4730 * x = 0, which are required for a semiring.  Richer structures do not
  4731 inherit from semiring_0 anymore, because this property is a theorem
  4732 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4733 there is more to prove, but this is mostly trivial.
  4734 
  4735 * Class "recpower" is generalized to arbitrary monoids, not just
  4736 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4737 commutativity or semiring properties additionally.
  4738 
  4739 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4740 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4741 better use 'abbreviation'.
  4742 
  4743 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4744 
  4745 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4746 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4747 significant changes for setting up numeral syntax for types:
  4748   - New constants Numeral.pred and Numeral.succ instead
  4749       of former Numeral.bin_pred and Numeral.bin_succ.
  4750   - Use integer operations instead of bin_add, bin_mult and so on.
  4751   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4752   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4753 
  4754 See src/HOL/Integ/IntArith.thy for an example setup.
  4755 
  4756 * Command 'normal_form' computes the normal form of a term that may
  4757 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4758 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4759 heavy-duty computations because the functions are compiled to ML
  4760 first.  Correspondingly, a method "normalization" is provided.  See
  4761 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4762 
  4763 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4764 25 like -->); output depends on the "iff" print_mode, the default is
  4765 "A = B" (with priority 50).
  4766 
  4767 * Relations less (<) and less_eq (<=) are also available on type bool.
  4768 Modified syntax to disallow nesting without explicit parentheses,
  4769 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4770 INCOMPATIBILITY.
  4771 
  4772 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4773 
  4774 * Relation composition operator "op O" now has precedence 75 and binds
  4775 stronger than union and intersection. INCOMPATIBILITY.
  4776 
  4777 * The old set interval syntax "{m..n(}" (and relatives) has been
  4778 removed.  Use "{m..<n}" (and relatives) instead.
  4779 
  4780 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4781 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4782 ``declare [[simproc del: neq]]''.
  4783 
  4784 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4785 True/False.
  4786 
  4787 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4788 
  4789 * Theorem setsum_mult renamed to setsum_right_distrib.
  4790 
  4791 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4792 ``rule'' method.
  4793 
  4794 * Reimplemented methods "sat" and "satx", with several improvements:
  4795 goals no longer need to be stated as "<prems> ==> False", equivalences
  4796 (i.e. "=" on type bool) are handled, variable names of the form
  4797 "lit_<n>" are no longer reserved, significant speedup.
  4798 
  4799 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4800 zChaff is still supported as well.
  4801 
  4802 * 'inductive' and 'datatype': provide projections of mutual rules,
  4803 bundled as foo_bar.inducts;
  4804 
  4805 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4806 Library.
  4807 
  4808 * Library: moved theory Accessible_Part to main HOL.
  4809 
  4810 * Library: added theory Coinductive_List of potentially infinite lists
  4811 as greatest fixed-point.
  4812 
  4813 * Library: added theory AssocList which implements (finite) maps as
  4814 association lists.
  4815 
  4816 * Method "evaluation" solves goals (i.e. a boolean expression)
  4817 efficiently by compiling it to ML.  The goal is "proved" (via an
  4818 oracle) if it evaluates to True.
  4819 
  4820 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4821 also when invoked by the simplifier.  This results in the Simplifier
  4822 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4823 Configuration option fast_arith_split_limit=0 recovers the old
  4824 behavior.
  4825 
  4826 * Support for hex (0x20) and binary (0b1001) numerals.
  4827 
  4828 * New method: reify eqs (t), where eqs are equations for an
  4829 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4830 parameter, computes a term s::'b and a list xs::'a list and proves the
  4831 theorem I xs s = t. This is also known as reification or quoting. The
  4832 resulting theorem is applied to the subgoal to substitute t with I xs
  4833 s.  If t is omitted, the subgoal itself is reified.
  4834 
  4835 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4836 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4837 where f is supposed to be a computable function (in the sense of code
  4838 generattion). The method uses reify to compute s and xs as above then
  4839 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4840 r and finally gets the theorem t = r, which is again applied to the
  4841 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4842 
  4843 * Reflection: Automatic reification now handels binding, an example is
  4844 available in src/HOL/ex/ReflectionEx.thy
  4845 
  4846 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4847 command 'statespace' that is similar to 'record', but introduces an
  4848 abstract specification based on the locale infrastructure instead of
  4849 HOL types.  This leads to extra flexibility in composing state spaces,
  4850 in particular multiple inheritance and renaming of components.
  4851 
  4852 
  4853 *** HOL-Complex ***
  4854 
  4855 * Hyperreal: Functions root and sqrt are now defined on negative real
  4856 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4857 Nonnegativity side conditions have been removed from many lemmas, so
  4858 that more subgoals may now be solved by simplification; potential
  4859 INCOMPATIBILITY.
  4860 
  4861 * Real: new type classes formalize real normed vector spaces and
  4862 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4863 and norm :: 'a => real.
  4864 
  4865 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4866 reals into other types. The overloaded constant Reals :: 'a set is now
  4867 defined as range of_real; potential INCOMPATIBILITY.
  4868 
  4869 * Real: proper support for ML code generation, including 'quickcheck'.
  4870 Reals are implemented as arbitrary precision rationals.
  4871 
  4872 * Hyperreal: Several constants that previously worked only for the
  4873 reals have been generalized, so they now work over arbitrary vector
  4874 spaces. Type annotations may need to be added in some cases; potential
  4875 INCOMPATIBILITY.
  4876 
  4877   Infinitesimal  :: ('a::real_normed_vector) star set
  4878   HFinite        :: ('a::real_normed_vector) star set
  4879   HInfinite      :: ('a::real_normed_vector) star set
  4880   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4881   monad          :: ('a::real_normed_vector) star => 'a star set
  4882   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4883   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4884   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4885   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4886   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4887   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4888   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4889   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4890   sgn            :: 'a::real_normed_vector => 'a
  4891   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4892 
  4893 * Complex: Some complex-specific constants are now abbreviations for
  4894 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4895 hnorm.  Other constants have been entirely removed in favor of the
  4896 polymorphic versions (INCOMPATIBILITY):
  4897 
  4898   approx        <-- capprox
  4899   HFinite       <-- CFinite
  4900   HInfinite     <-- CInfinite
  4901   Infinitesimal <-- CInfinitesimal
  4902   monad         <-- cmonad
  4903   galaxy        <-- cgalaxy
  4904   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4905   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4906   (ns)deriv     <-- (ns)cderiv
  4907 
  4908 
  4909 *** HOL-Algebra ***
  4910 
  4911 * Formalisation of ideals and the quotient construction over rings.
  4912 
  4913 * Order and lattice theory no longer based on records.
  4914 INCOMPATIBILITY.
  4915 
  4916 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4917 greatest_closed.  INCOMPATIBILITY.
  4918 
  4919 * Method algebra is now set up via an attribute.  For examples see
  4920 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4921 of algebraic structures.
  4922 
  4923 * Renamed theory CRing to Ring.
  4924 
  4925 
  4926 *** HOL-Nominal ***
  4927 
  4928 * Substantial, yet incomplete support for nominal datatypes (binding
  4929 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4930 src/HOL/Nominal/Examples.  Prospective users should consult
  4931 http://isabelle.in.tum.de/nominal/
  4932 
  4933 
  4934 *** ML ***
  4935 
  4936 * ML basics: just one true type int, which coincides with IntInf.int
  4937 (even on SML/NJ).
  4938 
  4939 * ML within Isar: antiquotations allow to embed statically-checked
  4940 formal entities in the source, referring to the context available at
  4941 compile-time.  For example:
  4942 
  4943 ML {* @{sort "{zero,one}"} *}
  4944 ML {* @{typ "'a => 'b"} *}
  4945 ML {* @{term "%x. x"} *}
  4946 ML {* @{prop "x == y"} *}
  4947 ML {* @{ctyp "'a => 'b"} *}
  4948 ML {* @{cterm "%x. x"} *}
  4949 ML {* @{cprop "x == y"} *}
  4950 ML {* @{thm asm_rl} *}
  4951 ML {* @{thms asm_rl} *}
  4952 ML {* @{type_name c} *}
  4953 ML {* @{type_syntax c} *}
  4954 ML {* @{const_name c} *}
  4955 ML {* @{const_syntax c} *}
  4956 ML {* @{context} *}
  4957 ML {* @{theory} *}
  4958 ML {* @{theory Pure} *}
  4959 ML {* @{theory_ref} *}
  4960 ML {* @{theory_ref Pure} *}
  4961 ML {* @{simpset} *}
  4962 ML {* @{claset} *}
  4963 ML {* @{clasimpset} *}
  4964 
  4965 The same works for sources being ``used'' within an Isar context.
  4966 
  4967 * ML in Isar: improved error reporting; extra verbosity with
  4968 ML_Context.trace enabled.
  4969 
  4970 * Pure/General/table.ML: the join operations now works via exceptions
  4971 DUP/SAME instead of type option. This is simpler in simple cases, and
  4972 admits slightly more efficient complex applications.
  4973 
  4974 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4975 use Context.generic instead of just theory.
  4976 
  4977 * Pure: datatype Context.generic joins theory/Proof.context and
  4978 provides some facilities for code that works in either kind of
  4979 context, notably GenericDataFun for uniform theory and proof data.
  4980 
  4981 * Pure: simplified internal attribute type, which is now always
  4982 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4983 local (Proof.context) attributes have been discontinued, while
  4984 minimizing code duplication. Thm.rule_attribute and
  4985 Thm.declaration_attribute build canonical attributes; see also structure
  4986 Context for further operations on Context.generic, notably
  4987 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4988 declarations and definitions.
  4989 
  4990 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4991 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4992 init only required for impure data. INCOMPATIBILITY: empty really need
  4993 to be empty (no dependencies on theory content!)
  4994 
  4995 * Pure/kernel: consts certification ignores sort constraints given in
  4996 signature declarations. (This information is not relevant to the
  4997 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4998 potential INCOMPATIBILITY.
  4999 
  5000 * Pure: axiomatic type classes are now purely definitional, with
  5001 explicit proofs of class axioms and super class relations performed
  5002 internally. See Pure/axclass.ML for the main internal interfaces --
  5003 notably AxClass.define_class supercedes AxClass.add_axclass, and
  5004 AxClass.axiomatize_class/classrel/arity supersede
  5005 Sign.add_classes/classrel/arities.
  5006 
  5007 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  5008 global/local versions on theory vs. Proof.context have been
  5009 discontinued; Attrib.syntax and Method.syntax have been adapted
  5010 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  5011 attributes, methods, etc.
  5012 
  5013 * Pure: several functions of signature "... -> theory -> theory * ..."
  5014 have been reoriented to "... -> theory -> ... * theory" in order to
  5015 allow natural usage in combination with the ||>, ||>>, |-> and
  5016 fold_map combinators.
  5017 
  5018 * Pure: official theorem names (closed derivations) and additional
  5019 comments (tags) are now strictly separate.  Name hints -- which are
  5020 maintained as tags -- may be attached any time without affecting the
  5021 derivation.
  5022 
  5023 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  5024 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  5025 achieve the old behaviour.
  5026 
  5027 * Pure: the "Goal" constant is now called "prop", supporting a
  5028 slightly more general idea of ``protecting'' meta-level rule
  5029 statements.
  5030 
  5031 * Pure: Logic.(un)varify only works in a global context, which is now
  5032 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  5033 Logic.legacy_(un)varify as temporary workaround.
  5034 
  5035 * Pure: structure Name provides scalable operations for generating
  5036 internal variable names, notably Name.variants etc.  This replaces
  5037 some popular functions from term.ML:
  5038 
  5039   Term.variant		->  Name.variant
  5040   Term.variantlist	->  Name.variant_list
  5041   Term.invent_names	->  Name.invent_list
  5042 
  5043 Note that low-level renaming rarely occurs in new code -- operations
  5044 from structure Variable are used instead (see below).
  5045 
  5046 * Pure: structure Variable provides fundamental operations for proper
  5047 treatment of fixed/schematic variables in a context.  For example,
  5048 Variable.import introduces fixes for schematics of given facts and
  5049 Variable.export reverses the effect (up to renaming) -- this replaces
  5050 various freeze_thaw operations.
  5051 
  5052 * Pure: structure Goal provides simple interfaces for
  5053 init/conclude/finish and tactical prove operations (replacing former
  5054 Tactic.prove).  Goal.prove is the canonical way to prove results
  5055 within a given context; Goal.prove_global is a degraded version for
  5056 theory level goals, including a global Drule.standard.  Note that
  5057 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  5058 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  5059 in a locale context).
  5060 
  5061 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  5062 and type checking (Syntax.check_term etc.), with common combinations
  5063 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  5064 which are considered legacy and await removal.
  5065 
  5066 * Pure/Syntax: generic interfaces for type unchecking
  5067 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  5068 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  5069 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  5070 available for convenience, but refer to the very same operations using
  5071 a mere theory instead of a full context.
  5072 
  5073 * Isar: simplified treatment of user-level errors, using exception
  5074 ERROR of string uniformly.  Function error now merely raises ERROR,
  5075 without any side effect on output channels.  The Isar toplevel takes
  5076 care of proper display of ERROR exceptions.  ML code may use plain
  5077 handle/can/try; cat_error may be used to concatenate errors like this:
  5078 
  5079   ... handle ERROR msg => cat_error msg "..."
  5080 
  5081 Toplevel ML code (run directly or through the Isar toplevel) may be
  5082 embedded into the Isar toplevel with exception display/debug like
  5083 this:
  5084 
  5085   Isar.toplevel (fn () => ...)
  5086 
  5087 INCOMPATIBILITY, removed special transform_error facilities, removed
  5088 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  5089 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  5090 -- use plain ERROR instead.
  5091 
  5092 * Isar: theory setup now has type (theory -> theory), instead of a
  5093 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  5094 
  5095 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  5096 ProofContext.debug/verbose flags.
  5097 
  5098 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  5099 theory before entering a proof state.  Transactions now always see a
  5100 quasi-functional intermediate checkpoint, both in interactive and
  5101 batch mode.
  5102 
  5103 * Isar: simplified interfaces for outer syntax.  Renamed
  5104 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  5105 OuterSyntax.add_parsers -- this functionality is now included in
  5106 OuterSyntax.command etc.  INCOMPATIBILITY.
  5107 
  5108 * Simplifier: the simpset of a running simplification process now
  5109 contains a proof context (cf. Simplifier.the_context), which is the
  5110 very context that the initial simpset has been retrieved from (by
  5111 simpset_of/local_simpset_of).  Consequently, all plug-in components
  5112 (solver, looper etc.) may depend on arbitrary proof data.
  5113 
  5114 * Simplifier.inherit_context inherits the proof context (plus the
  5115 local bounds) of the current simplification process; any simproc
  5116 etc. that calls the Simplifier recursively should do this!  Removed
  5117 former Simplifier.inherit_bounds, which is already included here --
  5118 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  5119 specify an explicit context using Simplifier.context/theory_context.
  5120 
  5121 * Simplifier/Classical Reasoner: more abstract interfaces
  5122 change_simpset/claset for modifying the simpset/claset reference of a
  5123 theory; raw versions simpset/claset_ref etc. have been discontinued --
  5124 INCOMPATIBILITY.
  5125 
  5126 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  5127 "Trueprop" etc.
  5128 
  5129 
  5130 *** System ***
  5131 
  5132 * settings: the default heap location within ISABELLE_HOME_USER now
  5133 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  5134 Isabelle installations.
  5135 
  5136 * isabelle-process: option -S (secure mode) disables some critical
  5137 operations, notably runtime compilation and evaluation of ML source
  5138 code.
  5139 
  5140 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  5141 
  5142 * Support for parallel execution, using native multicore support of
  5143 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  5144 independent theories, according to the given theory header
  5145 specifications. The maximum number of worker threads is specified via
  5146 usedir option -M or the "max-threads" setting in Proof General. A
  5147 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  5148 to 6 on a 8-core machine.  User-code needs to observe certain
  5149 guidelines for thread-safe programming, see appendix A in the Isar
  5150 Implementation manual.
  5151 
  5152 
  5153 
  5154 New in Isabelle2005 (October 2005)
  5155 ----------------------------------
  5156 
  5157 *** General ***
  5158 
  5159 * Theory headers: the new header syntax for Isar theories is
  5160 
  5161   theory <name>
  5162   imports <theory1> ... <theoryN>
  5163   uses <file1> ... <fileM>
  5164   begin
  5165 
  5166 where the 'uses' part is optional.  The previous syntax
  5167 
  5168   theory <name> = <theory1> + ... + <theoryN>:
  5169 
  5170 will disappear in the next release.  Use isatool fixheaders to convert
  5171 existing theory files.  Note that there is no change in ancient
  5172 non-Isar theories now, but these will disappear soon.
  5173 
  5174 * Theory loader: parent theories can now also be referred to via
  5175 relative and absolute paths.
  5176 
  5177 * Command 'find_theorems' searches for a list of criteria instead of a
  5178 list of constants. Known criteria are: intro, elim, dest, name:string,
  5179 simp:term, and any term. Criteria can be preceded by '-' to select
  5180 theorems that do not match. Intro, elim, dest select theorems that
  5181 match the current goal, name:s selects theorems whose fully qualified
  5182 name contain s, and simp:term selects all simplification rules whose
  5183 lhs match term.  Any other term is interpreted as pattern and selects
  5184 all theorems matching the pattern. Available in ProofGeneral under
  5185 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  5186 
  5187   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  5188 
  5189 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  5190 matching the current goal as introduction rule and not having "HOL."
  5191 in their name (i.e. not being defined in theory HOL).
  5192 
  5193 * Command 'thms_containing' has been discontinued in favour of
  5194 'find_theorems'; INCOMPATIBILITY.
  5195 
  5196 * Communication with Proof General is now 8bit clean, which means that
  5197 Unicode text in UTF-8 encoding may be used within theory texts (both
  5198 formal and informal parts).  Cf. option -U of the Isabelle Proof
  5199 General interface.  Here are some simple examples (cf. src/HOL/ex):
  5200 
  5201   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  5202   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  5203 
  5204 * Improved efficiency of the Simplifier and, to a lesser degree, the
  5205 Classical Reasoner.  Typical big applications run around 2 times
  5206 faster.
  5207 
  5208 
  5209 *** Document preparation ***
  5210 
  5211 * Commands 'display_drafts' and 'print_drafts' perform simple output
  5212 of raw sources.  Only those symbols that do not require additional
  5213 LaTeX packages (depending on comments in isabellesym.sty) are
  5214 displayed properly, everything else is left verbatim.  isatool display
  5215 and isatool print are used as front ends (these are subject to the
  5216 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  5217 
  5218 * Command tags control specific markup of certain regions of text,
  5219 notably folding and hiding.  Predefined tags include "theory" (for
  5220 theory begin and end), "proof" for proof commands, and "ML" for
  5221 commands involving ML code; the additional tags "visible" and
  5222 "invisible" are unused by default.  Users may give explicit tag
  5223 specifications in the text, e.g. ''by %invisible (auto)''.  The
  5224 interpretation of tags is determined by the LaTeX job during document
  5225 preparation: see option -V of isatool usedir, or options -n and -t of
  5226 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  5227 \isadroptag.
  5228 
  5229 Several document versions may be produced at the same time via isatool
  5230 usedir (the generated index.html will link all of them).  Typical
  5231 specifications include ''-V document=theory,proof,ML'' to present
  5232 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  5233 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  5234 these parts without any formal replacement text.  The Isabelle site
  5235 default settings produce ''document'' and ''outline'' versions as
  5236 specified above.
  5237 
  5238 * Several new antiquotations:
  5239 
  5240   @{term_type term} prints a term with its type annotated;
  5241 
  5242   @{typeof term} prints the type of a term;
  5243 
  5244   @{const const} is the same as @{term const}, but checks that the
  5245   argument is a known logical constant;
  5246 
  5247   @{term_style style term} and @{thm_style style thm} print a term or
  5248   theorem applying a "style" to it
  5249 
  5250   @{ML text}
  5251 
  5252 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5253 definitions, equations, inequations etc., 'concl' printing only the
  5254 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5255 to print the specified premise.  TermStyle.add_style provides an ML
  5256 interface for introducing further styles.  See also the "LaTeX Sugar"
  5257 document practical applications.  The ML antiquotation prints
  5258 type-checked ML expressions verbatim.
  5259 
  5260 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5261 and 'text' support optional locale specification '(in loc)', which
  5262 specifies the default context for interpreting antiquotations.  For
  5263 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5264 
  5265 * Option 'locale=NAME' of antiquotations specifies an alternative
  5266 context interpreting the subsequent argument.  For example: @{thm
  5267 [locale=lattice] inf_assoc}.
  5268 
  5269 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5270 a proof context.
  5271 
  5272 * Proper output of antiquotations for theory commands involving a
  5273 proof context (such as 'locale' or 'theorem (in loc) ...').
  5274 
  5275 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5276 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5277 
  5278 * isatool usedir: new option -C (default true) controls whether option
  5279 -D should include a copy of the original document directory; -C false
  5280 prevents unwanted effects such as copying of administrative CVS data.
  5281 
  5282 
  5283 *** Pure ***
  5284 
  5285 * Considerably improved version of 'constdefs' command.  Now performs
  5286 automatic type-inference of declared constants; additional support for
  5287 local structure declarations (cf. locales and HOL records), see also
  5288 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5289 sequential dependencies of definitions within a single 'constdefs'
  5290 section; moreover, the declared name needs to be an identifier.  If
  5291 all fails, consider to fall back on 'consts' and 'defs' separately.
  5292 
  5293 * Improved indexed syntax and implicit structures.  First of all,
  5294 indexed syntax provides a notational device for subscripted
  5295 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5296 expressions.  Secondly, in a local context with structure
  5297 declarations, number indexes \<^sub>n or the empty index (default
  5298 number 1) refer to a certain fixed variable implicitly; option
  5299 show_structs controls printing of implicit structures.  Typical
  5300 applications of these concepts involve record types and locales.
  5301 
  5302 * New command 'no_syntax' removes grammar declarations (and
  5303 translations) resulting from the given syntax specification, which is
  5304 interpreted in the same manner as for the 'syntax' command.
  5305 
  5306 * 'Advanced' translation functions (parse_translation etc.) may depend
  5307 on the signature of the theory context being presently used for
  5308 parsing/printing, see also isar-ref manual.
  5309 
  5310 * Improved 'oracle' command provides a type-safe interface to turn an
  5311 ML expression of type theory -> T -> term into a primitive rule of
  5312 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5313 is already included here); see also FOL/ex/IffExample.thy;
  5314 INCOMPATIBILITY.
  5315 
  5316 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5317 before); "cI" is no longer bound, use "c.intro" instead.
  5318 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5319 axclasses vs. locales.
  5320 
  5321 * Improved internal renaming of symbolic identifiers -- attach primes
  5322 instead of base 26 numbers.
  5323 
  5324 * New flag show_question_marks controls printing of leading question
  5325 marks in schematic variable names.
  5326 
  5327 * In schematic variable names, *any* symbol following \<^isub> or
  5328 \<^isup> is now treated as part of the base name.  For example, the
  5329 following works without printing of awkward ".0" indexes:
  5330 
  5331   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5332     by simp
  5333 
  5334 * Inner syntax includes (*(*nested*) comments*).
  5335 
  5336 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5337 annotations as "(00...)".
  5338 
  5339 * Clear separation of logical types and nonterminals, where the latter
  5340 may only occur in 'syntax' specifications or type abbreviations.
  5341 Before that distinction was only partially implemented via type class
  5342 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5343 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5344 exotic syntax specifications may require further adaption
  5345 (e.g. Cube/Cube.thy).
  5346 
  5347 * Removed obsolete type class "logic", use the top sort {} instead.
  5348 Note that non-logical types should be declared as 'nonterminals'
  5349 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5350 specifications.
  5351 
  5352 * Attributes 'induct' and 'cases': type or set names may now be
  5353 locally fixed variables as well.
  5354 
  5355 * Simplifier: can now control the depth to which conditional rewriting
  5356 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5357 Limit.
  5358 
  5359 * Simplifier: simplification procedures may now take the current
  5360 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5361 interface), which is very useful for calling the Simplifier
  5362 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5363 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5364 low-level mk_simproc no longer applies Logic.varify internally, to
  5365 allow for use in a context of fixed variables.
  5366 
  5367 * thin_tac now works even if the assumption being deleted contains !!
  5368 or ==>.  More generally, erule now works even if the major premise of
  5369 the elimination rule contains !! or ==>.
  5370 
  5371 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5372 
  5373 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5374 from Pure, which contains all common declarations already.  Both
  5375 theories are defined via plain Isabelle/Isar .thy files.
  5376 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5377 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5378 use isatool fixcpure to adapt your theory and ML sources.
  5379 
  5380 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5381 selections of theorems in named facts via index ranges.
  5382 
  5383 * 'print_theorems': in theory mode, really print the difference
  5384 wrt. the last state (works for interactive theory development only),
  5385 in proof mode print all local facts (cf. 'print_facts');
  5386 
  5387 * 'hide': option '(open)' hides only base names.
  5388 
  5389 * More efficient treatment of intermediate checkpoints in interactive
  5390 theory development.
  5391 
  5392 * Code generator is now invoked via code_module (incremental code
  5393 generation) and code_library (modular code generation, ML structures
  5394 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5395 must be quoted when used as identifiers.
  5396 
  5397 * New 'value' command for reading, evaluating and printing terms using
  5398 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5399 quoted when used as identifier.
  5400 
  5401 
  5402 *** Locales ***
  5403 
  5404 * New commands for the interpretation of locale expressions in
  5405 theories (1), locales (2) and proof contexts (3).  These generate
  5406 proof obligations from the expression specification.  After the
  5407 obligations have been discharged, theorems of the expression are added
  5408 to the theory, target locale or proof context.  The synopsis of the
  5409 commands is a follows:
  5410 
  5411   (1) interpretation expr inst
  5412   (2) interpretation target < expr
  5413   (3) interpret expr inst
  5414 
  5415 Interpretation in theories and proof contexts require a parameter
  5416 instantiation of terms from the current context.  This is applied to
  5417 specifications and theorems of the interpreted expression.
  5418 Interpretation in locales only permits parameter renaming through the
  5419 locale expression.  Interpretation is smart in that interpretations
  5420 that are active already do not occur in proof obligations, neither are
  5421 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5422 inspect active interpretations of a particular locale.  For details,
  5423 see the Isar Reference manual.  Examples can be found in
  5424 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5425 
  5426 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5427 'interpret' instead.
  5428 
  5429 * New context element 'constrains' for adding type constraints to
  5430 parameters.
  5431 
  5432 * Context expressions: renaming of parameters with syntax
  5433 redeclaration.
  5434 
  5435 * Locale declaration: 'includes' disallowed.
  5436 
  5437 * Proper static binding of attribute syntax -- i.e. types / terms /
  5438 facts mentioned as arguments are always those of the locale definition
  5439 context, independently of the context of later invocations.  Moreover,
  5440 locale operations (renaming and type / term instantiation) are applied
  5441 to attribute arguments as expected.
  5442 
  5443 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5444 actual attributes; rare situations may require Attrib.attribute to
  5445 embed those attributes into Attrib.src that lack concrete syntax.
  5446 Attribute implementations need to cooperate properly with the static
  5447 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5448 Attrib.XXX_thm etc. already do the right thing without further
  5449 intervention.  Only unusual applications -- such as "where" or "of"
  5450 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5451 on the context and the facts involved -- may have to assign parsed
  5452 values to argument tokens explicitly.
  5453 
  5454 * Changed parameter management in theorem generation for long goal
  5455 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5456 theorem statement in rare situations.
  5457 
  5458 * Locale inspection command 'print_locale' omits notes elements.  Use
  5459 'print_locale!' to have them included in the output.
  5460 
  5461 
  5462 *** Provers ***
  5463 
  5464 * Provers/hypsubst.ML: improved version of the subst method, for
  5465 single-step rewriting: it now works in bound variable contexts. New is
  5466 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5467 rewrite a different subterm than the original subst method, which is
  5468 still available as 'simplesubst'.
  5469 
  5470 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5471 and quasi orders.
  5472 
  5473 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5474 reflexive-transitive closure of relations.
  5475 
  5476 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5477 limit (previously hard-coded with a value of 20) user-definable.
  5478 
  5479 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5480 is peformed already.  Object-logics merely need to finish their
  5481 initial simpset configuration as before.  INCOMPATIBILITY.
  5482 
  5483 
  5484 *** HOL ***
  5485 
  5486 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5487 
  5488   syntax (epsilon)
  5489     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5490 
  5491 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5492 and x-symbol; use option '-m epsilon' to get it actually printed.
  5493 Moreover, the mathematically important symbolic identifier \<epsilon>
  5494 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5495 
  5496 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5497 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5498 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5499 support corresponding Isar calculations.
  5500 
  5501 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5502 instead of ":".
  5503 
  5504 * theory SetInterval: changed the syntax for open intervals:
  5505 
  5506   Old       New
  5507   {..n(}    {..<n}
  5508   {)n..}    {n<..}
  5509   {m..n(}   {m..<n}
  5510   {)m..n}   {m<..n}
  5511   {)m..n(}  {m<..<n}
  5512 
  5513 The old syntax is still supported but will disappear in the next
  5514 release.  For conversion use the following Emacs search and replace
  5515 patterns (these are not perfect but work quite well):
  5516 
  5517   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5518   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5519 
  5520 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5521 equalities in commutative rings; method 'algebra' provides a generic
  5522 interface.
  5523 
  5524 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5525 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5526 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5527 be a tuple pattern.
  5528 
  5529 Some new syntax forms are available:
  5530 
  5531   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5532   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5533   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5534   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5535 
  5536 The latter form "\<Sum>x < k. e" used to be based on a separate
  5537 function "Summation", which has been discontinued.
  5538 
  5539 * theory Finite_Set: in structured induction proofs, the insert case
  5540 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5541 (insert F x)'.
  5542 
  5543 * The 'refute' command has been extended to support a much larger
  5544 fragment of HOL, including axiomatic type classes, constdefs and
  5545 typedefs, inductive datatypes and recursion.
  5546 
  5547 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5548 Requires zChaff with proof generation to be installed.  See
  5549 HOL/ex/SAT_Examples.thy for examples.
  5550 
  5551 * Datatype induction via method 'induct' now preserves the name of the
  5552 induction variable. For example, when proving P(xs::'a list) by
  5553 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5554 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5555 in unstructured proof scripts.
  5556 
  5557 * Reworked implementation of records.  Improved scalability for
  5558 records with many fields, avoiding performance problems for type
  5559 inference. Records are no longer composed of nested field types, but
  5560 of nested extension types. Therefore the record type only grows linear
  5561 in the number of extensions and not in the number of fields.  The
  5562 top-level (users) view on records is preserved.  Potential
  5563 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5564 old record representation. The type generated for a record is called
  5565 <record_name>_ext_type.
  5566 
  5567 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5568 proofs triggered by a record definition or a simproc (if
  5569 quick_and_dirty is enabled).  Definitions of large records can take
  5570 quite long.
  5571 
  5572 New simproc record_upd_simproc for simplification of multiple record
  5573 updates enabled by default.  Moreover, trivial updates are also
  5574 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5575 occasionally, since simplification is more powerful by default.
  5576 
  5577 * typedef: proper support for polymorphic sets, which contain extra
  5578 type-variables in the term.
  5579 
  5580 * Simplifier: automatically reasons about transitivity chains
  5581 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5582 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5583 old proofs break occasionally as simplification may now solve more
  5584 goals than previously.
  5585 
  5586 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5587 present.  Works for all partial orders (class "order"), in particular
  5588 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5589 just like y <= x.
  5590 
  5591 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5592 bound variable or a constant then the let is unfolded.  Otherwise
  5593 first a is simplified to b, and then f b is simplified to g. If
  5594 possible we abstract b from g arriving at "let x = b in h x",
  5595 otherwise we unfold the let and arrive at g.  The simproc can be
  5596 enabled/disabled by the reference use_let_simproc.  Potential
  5597 INCOMPATIBILITY since simplification is more powerful by default.
  5598 
  5599 * Classical reasoning: the meson method now accepts theorems as arguments.
  5600 
  5601 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5602 jobs to provide advice on the provability of subgoals.
  5603 
  5604 * Theory OrderedGroup and Ring_and_Field: various additions and
  5605 improvements to faciliate calculations involving equalities and
  5606 inequalities.
  5607 
  5608 The following theorems have been eliminated or modified
  5609 (INCOMPATIBILITY):
  5610 
  5611   abs_eq             now named abs_of_nonneg
  5612   abs_of_ge_0        now named abs_of_nonneg
  5613   abs_minus_eq       now named abs_of_nonpos
  5614   imp_abs_id         now named abs_of_nonneg
  5615   imp_abs_neg_id     now named abs_of_nonpos
  5616   mult_pos           now named mult_pos_pos
  5617   mult_pos_le        now named mult_nonneg_nonneg
  5618   mult_pos_neg_le    now named mult_nonneg_nonpos
  5619   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5620   mult_neg           now named mult_neg_neg
  5621   mult_neg_le        now named mult_nonpos_nonpos
  5622 
  5623 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5624      
  5625      zero_le_square
  5626      not_square_less_zero 
  5627 
  5628   The following lemmas have been deleted from Real/RealPow:
  5629   
  5630      realpow_zero_zero
  5631      realpow_two
  5632      realpow_less
  5633      zero_le_power
  5634      realpow_two_le
  5635      abs_realpow_two
  5636      realpow_two_abs     
  5637 
  5638 * Theory Parity: added rules for simplifying exponents.
  5639 
  5640 * Theory List:
  5641 
  5642 The following theorems have been eliminated or modified
  5643 (INCOMPATIBILITY):
  5644 
  5645   list_all_Nil       now named list_all.simps(1)
  5646   list_all_Cons      now named list_all.simps(2)
  5647   list_all_conv      now named list_all_iff
  5648   set_mem_eq         now named mem_iff
  5649 
  5650 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5651 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5652 
  5653 
  5654 *** HOL-Complex ***
  5655 
  5656 * Theory RealDef: better support for embedding natural numbers and
  5657 integers in the reals.
  5658 
  5659 The following theorems have been eliminated or modified
  5660 (INCOMPATIBILITY):
  5661 
  5662   exp_ge_add_one_self  now requires no hypotheses
  5663   real_of_int_add      reversed direction of equality (use [symmetric])
  5664   real_of_int_minus    reversed direction of equality (use [symmetric])
  5665   real_of_int_diff     reversed direction of equality (use [symmetric])
  5666   real_of_int_mult     reversed direction of equality (use [symmetric])
  5667 
  5668 * Theory RComplete: expanded support for floor and ceiling functions.
  5669 
  5670 * Theory Ln is new, with properties of the natural logarithm
  5671 
  5672 * Hyperreal: There is a new type constructor "star" for making
  5673 nonstandard types.  The old type names are now type synonyms:
  5674 
  5675   hypreal = real star
  5676   hypnat = nat star
  5677   hcomplex = complex star
  5678 
  5679 * Hyperreal: Many groups of similarly-defined constants have been
  5680 replaced by polymorphic versions (INCOMPATIBILITY):
  5681 
  5682   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5683 
  5684   starset      <-- starsetNat, starsetC
  5685   *s*          <-- *sNat*, *sc*
  5686   starset_n    <-- starsetNat_n, starsetC_n
  5687   *sn*         <-- *sNatn*, *scn*
  5688   InternalSets <-- InternalNatSets, InternalCSets
  5689 
  5690   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5691   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5692   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5693   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5694   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5695 
  5696 * Hyperreal: Many type-specific theorems have been removed in favor of
  5697 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5698 
  5699   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5700   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5701   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5702   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5703   right_minus <-- hypreal_add_minus
  5704   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5705   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5706   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5707   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5708   mult_1_right <-- hcomplex_mult_one_right
  5709   mult_zero_left <-- hcomplex_mult_zero_left
  5710   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5711   right_distrib <-- hypnat_add_mult_distrib2
  5712   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5713   right_inverse <-- hypreal_mult_inverse
  5714   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5715   order_refl <-- {hypreal,hypnat}_le_refl
  5716   order_trans <-- {hypreal,hypnat}_le_trans
  5717   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5718   order_less_le <-- {hypreal,hypnat}_less_le
  5719   linorder_linear <-- {hypreal,hypnat}_le_linear
  5720   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5721   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5722   add_nonneg_nonneg <-- hypreal_le_add_order
  5723 
  5724 * Hyperreal: Separate theorems having to do with type-specific
  5725 versions of constants have been merged into theorems that apply to the
  5726 new polymorphic constants (INCOMPATIBILITY):
  5727 
  5728   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5729   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5730   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5731   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5732   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5733   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5734   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5735   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5736   STAR_diff <-- {STAR,STARC}_diff
  5737   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5738     STARC_hcomplex_of_complex}_image_subset
  5739   starset_n_Un <-- starset{Nat,C}_n_Un
  5740   starset_n_Int <-- starset{Nat,C}_n_Int
  5741   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5742   starset_n_diff <-- starset{Nat,C}_n_diff
  5743   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5744   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5745   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5746   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5747   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5748   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5749   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5750   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5751   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5752   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5753   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5754   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5755   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5756   starfun_diff <-- starfun{C,RC,CR}_diff
  5757   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5758   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5759   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5760   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5761   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5762   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5763   starfun_Id <-- starfunC_Id
  5764   starfun_approx <-- starfun{Nat,CR}_approx
  5765   starfun_capprox <-- starfun{C,RC}_capprox
  5766   starfun_abs <-- starfunNat_rabs
  5767   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5768   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5769   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5770   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5771   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5772   starfun_add_approx <-- starfunCR_add_approx
  5773   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5774   starfun_divide <-- starfun{C,CR,RC}_divide
  5775   starfun_n <-- starfun{Nat,C}_n
  5776   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5777   starfun_n_add <-- starfun{Nat,C}_n_add
  5778   starfun_n_add_minus <-- starfunNat_n_add_minus
  5779   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5780   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5781   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5782 
  5783   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5784   star_n_minus <-- {hypreal,hcomplex}_minus
  5785   star_n_diff <-- {hypreal,hcomplex}_diff
  5786   star_n_mult <-- {hypreal,hcomplex}_mult
  5787   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5788   star_n_le <-- {hypreal,hypnat}_le
  5789   star_n_less <-- {hypreal,hypnat}_less
  5790   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5791   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5792   star_n_abs <-- hypreal_hrabs
  5793   star_n_divide <-- hcomplex_divide
  5794 
  5795   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5796   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5797   star_of_diff <-- hypreal_of_real_diff
  5798   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5799   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5800   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5801   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5802   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5803   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5804   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5805   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5806   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5807   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5808   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5809   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5810   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5811   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5812   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5813   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5814   star_of_power <-- hypreal_of_real_power
  5815   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5816 
  5817 * Hyperreal: new method "transfer" that implements the transfer
  5818 principle of nonstandard analysis. With a subgoal that mentions
  5819 nonstandard types like "'a star", the command "apply transfer"
  5820 replaces it with an equivalent one that mentions only standard types.
  5821 To be successful, all free variables must have standard types; non-
  5822 standard variables must have explicit universal quantifiers.
  5823 
  5824 * Hyperreal: A theory of Taylor series.
  5825 
  5826 
  5827 *** HOLCF ***
  5828 
  5829 * Discontinued special version of 'constdefs' (which used to support
  5830 continuous functions) in favor of the general Pure one with full
  5831 type-inference.
  5832 
  5833 * New simplification procedure for solving continuity conditions; it
  5834 is much faster on terms with many nested lambda abstractions (cubic
  5835 instead of exponential time).
  5836 
  5837 * New syntax for domain package: selector names are now optional.
  5838 Parentheses should be omitted unless argument is lazy, for example:
  5839 
  5840   domain 'a stream = cons "'a" (lazy "'a stream")
  5841 
  5842 * New command 'fixrec' for defining recursive functions with pattern
  5843 matching; defining multiple functions with mutual recursion is also
  5844 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5845 sinr, or any data constructor defined by the domain package. The given
  5846 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5847 syntax and examples.
  5848 
  5849 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5850 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5851 but the proof obligation additionally includes an admissibility
  5852 requirement. The packages generate instances of class cpo or pcpo,
  5853 with continuity and strictness theorems for Rep and Abs.
  5854 
  5855 * HOLCF: Many theorems have been renamed according to a more standard naming
  5856 scheme (INCOMPATIBILITY):
  5857 
  5858   foo_inject:  "foo$x = foo$y ==> x = y"
  5859   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5860   foo_less:    "(foo$x << foo$y) = (x << y)"
  5861   foo_strict:  "foo$UU = UU"
  5862   foo_defined: "... ==> foo$x ~= UU"
  5863   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5864 
  5865 
  5866 *** ZF ***
  5867 
  5868 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5869 including the First Isomorphism Theorem (on quotienting by the kernel
  5870 of a homomorphism).
  5871 
  5872 * ZF/Simplifier: install second copy of type solver that actually
  5873 makes use of TC rules declared to Isar proof contexts (or locales);
  5874 the old version is still required for ML proof scripts.
  5875 
  5876 
  5877 *** Cube ***
  5878 
  5879 * Converted to Isar theory format; use locales instead of axiomatic
  5880 theories.
  5881 
  5882 
  5883 *** ML ***
  5884 
  5885 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5886 for ||>, ||>>, |>>,
  5887 
  5888 * Pure/library.ML no longer defines its own option datatype, but uses
  5889 that of the SML basis, which has constructors NONE and SOME instead of
  5890 None and Some, as well as exception Option.Option instead of OPTION.
  5891 The functions the, if_none, is_some, is_none have been adapted
  5892 accordingly, while Option.map replaces apsome.
  5893 
  5894 * Pure/library.ML: the exception LIST has been given up in favour of
  5895 the standard exceptions Empty and Subscript, as well as
  5896 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5897 superceded by the standard hd and tl functions etc.
  5898 
  5899 A number of basic list functions are no longer exported to the ML
  5900 toplevel, as they are variants of predefined functions.  The following
  5901 suggests how one can translate existing code:
  5902 
  5903     rev_append xs ys = List.revAppend (xs, ys)
  5904     nth_elem (i, xs) = List.nth (xs, i)
  5905     last_elem xs = List.last xs
  5906     flat xss = List.concat xss
  5907     seq fs = List.app fs
  5908     partition P xs = List.partition P xs
  5909     mapfilter f xs = List.mapPartial f xs
  5910 
  5911 * Pure/library.ML: several combinators for linear functional
  5912 transformations, notably reverse application and composition:
  5913 
  5914   x |> f                f #> g
  5915   (x, y) |-> f          f #-> g
  5916 
  5917 * Pure/library.ML: introduced/changed precedence of infix operators:
  5918 
  5919   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5920   infix 2 ?;
  5921   infix 3 o oo ooo oooo;
  5922   infix 4 ~~ upto downto;
  5923 
  5924 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5925 infix operators.
  5926 
  5927 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5928 fold_map support linear functional transformations and nesting.  For
  5929 example:
  5930 
  5931   fold f [x1, ..., xN] y =
  5932     y |> f x1 |> ... |> f xN
  5933 
  5934   (fold o fold) f [xs1, ..., xsN] y =
  5935     y |> fold f xs1 |> ... |> fold f xsN
  5936 
  5937   fold f [x1, ..., xN] =
  5938     f x1 #> ... #> f xN
  5939 
  5940   (fold o fold) f [xs1, ..., xsN] =
  5941     fold f xs1 #> ... #> fold f xsN
  5942 
  5943 * Pure/library.ML: the following selectors on type 'a option are
  5944 available:
  5945 
  5946   the:               'a option -> 'a  (*partial*)
  5947   these:             'a option -> 'a  where 'a = 'b list
  5948   the_default: 'a -> 'a option -> 'a
  5949   the_list:          'a option -> 'a list
  5950 
  5951 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5952 basic operations for association lists, following natural argument
  5953 order; moreover the explicit equality predicate passed here avoids
  5954 potentially expensive polymorphic runtime equality checks.
  5955 The old functions may be expressed as follows:
  5956 
  5957   assoc = uncurry (AList.lookup (op =))
  5958   assocs = these oo AList.lookup (op =)
  5959   overwrite = uncurry (AList.update (op =)) o swap
  5960 
  5961 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5962 
  5963   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5964   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5965 
  5966 replacing make_keylist and keyfilter (occassionally used)
  5967 Naive rewrites:
  5968 
  5969   make_keylist = AList.make
  5970   keyfilter = AList.find (op =)
  5971 
  5972 * eq_fst and eq_snd now take explicit equality parameter, thus
  5973   avoiding eqtypes. Naive rewrites:
  5974 
  5975     eq_fst = eq_fst (op =)
  5976     eq_snd = eq_snd (op =)
  5977 
  5978 * Removed deprecated apl and apr (rarely used).
  5979   Naive rewrites:
  5980 
  5981     apl (n, op) =>>= curry op n
  5982     apr (op, m) =>>= fn n => op (n, m)
  5983 
  5984 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5985 provides a reasonably efficient light-weight implementation of sets as
  5986 lists.
  5987 
  5988 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5989 few new operations; existing lookup and update are now curried to
  5990 follow natural argument order (for use with fold etc.);
  5991 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5992 
  5993 * Pure/General: output via the Isabelle channels of
  5994 writeln/warning/error etc. is now passed through Output.output, with a
  5995 hook for arbitrary transformations depending on the print_mode
  5996 (cf. Output.add_mode -- the first active mode that provides a output
  5997 function wins).  Already formatted output may be embedded into further
  5998 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5999 functions (string_of_term/cterm/thm etc.) is already marked raw to
  6000 accommodate easy composition of diagnostic messages etc.  Programmers
  6001 rarely need to care about Output.output or Output.raw at all, with
  6002 some notable exceptions: Output.output is required when bypassing the
  6003 standard channels (writeln etc.), or in token translations to produce
  6004 properly formatted results; Output.raw is required when capturing
  6005 already output material that will eventually be presented to the user
  6006 a second time.  For the default print mode, both Output.output and
  6007 Output.raw have no effect.
  6008 
  6009 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  6010 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  6011 cumulative results are displayed at the end of a batch session.
  6012 
  6013 * Pure/General: File.sysify_path and File.quote_sysify path have been
  6014 replaced by File.platform_path and File.shell_path (with appropriate
  6015 hooks).  This provides a clean interface for unusual systems where the
  6016 internal and external process view of file names are different.
  6017 
  6018 * Pure: more efficient orders for basic syntactic entities: added
  6019 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  6020 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  6021 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  6022 orders now -- potential INCOMPATIBILITY for code that depends on a
  6023 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  6024 Library.sort_strings on result).
  6025 
  6026 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  6027 fold_types traverse types/terms from left to right, observing natural
  6028 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  6029 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  6030 
  6031 * Pure: name spaces have been refined, with significant changes of the
  6032 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  6033 to extern(_table).  The plain name entry path is superceded by a
  6034 general 'naming' context, which also includes the 'policy' to produce
  6035 a fully qualified name and external accesses of a fully qualified
  6036 name; NameSpace.extend is superceded by context dependent
  6037 Sign.declare_name.  Several theory and proof context operations modify
  6038 the naming context.  Especially note Theory.restore_naming and
  6039 ProofContext.restore_naming to get back to a sane state; note that
  6040 Theory.add_path is no longer sufficient to recover from
  6041 Theory.absolute_path in particular.
  6042 
  6043 * Pure: new flags short_names (default false) and unique_names
  6044 (default true) for controlling output of qualified names.  If
  6045 short_names is set, names are printed unqualified.  If unique_names is
  6046 reset, the name prefix is reduced to the minimum required to achieve
  6047 the original result when interning again, even if there is an overlap
  6048 with earlier declarations.
  6049 
  6050 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  6051 now 'extend', and 'merge' gets an additional Pretty.pp argument
  6052 (useful for printing error messages).  INCOMPATIBILITY.
  6053 
  6054 * Pure: major reorganization of the theory context.  Type Sign.sg and
  6055 Theory.theory are now identified, referring to the universal
  6056 Context.theory (see Pure/context.ML).  Actual signature and theory
  6057 content is managed as theory data.  The old code and interfaces were
  6058 spread over many files and structures; the new arrangement introduces
  6059 considerable INCOMPATIBILITY to gain more clarity:
  6060 
  6061   Context -- theory management operations (name, identity, inclusion,
  6062     parents, ancestors, merge, etc.), plus generic theory data;
  6063 
  6064   Sign -- logical signature and syntax operations (declaring consts,
  6065     types, etc.), plus certify/read for common entities;
  6066 
  6067   Theory -- logical theory operations (stating axioms, definitions,
  6068     oracles), plus a copy of logical signature operations (consts,
  6069     types, etc.); also a few basic management operations (Theory.copy,
  6070     Theory.merge, etc.)
  6071 
  6072 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  6073 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  6074 for convenience -- they merely return the theory.
  6075 
  6076 * Pure: type Type.tsig is superceded by theory in most interfaces.
  6077 
  6078 * Pure: the Isar proof context type is already defined early in Pure
  6079 as Context.proof (note that ProofContext.context and Proof.context are
  6080 aliases, where the latter is the preferred name).  This enables other
  6081 Isabelle components to refer to that type even before Isar is present.
  6082 
  6083 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  6084 typeK, constK, axiomK, oracleK), but provide explicit operations for
  6085 any of these kinds.  For example, Sign.intern typeK is now
  6086 Sign.intern_type, Theory.hide_space Sign.typeK is now
  6087 Theory.hide_types.  Also note that former
  6088 Theory.hide_classes/types/consts are now
  6089 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  6090 internalize their arguments!  INCOMPATIBILITY.
  6091 
  6092 * Pure: get_thm interface (of PureThy and ProofContext) expects
  6093 datatype thmref (with constructors Name and NameSelection) instead of
  6094 plain string -- INCOMPATIBILITY;
  6095 
  6096 * Pure: cases produced by proof methods specify options, where NONE
  6097 means to remove case bindings -- INCOMPATIBILITY in
  6098 (RAW_)METHOD_CASES.
  6099 
  6100 * Pure: the following operations retrieve axioms or theorems from a
  6101 theory node or theory hierarchy, respectively:
  6102 
  6103   Theory.axioms_of: theory -> (string * term) list
  6104   Theory.all_axioms_of: theory -> (string * term) list
  6105   PureThy.thms_of: theory -> (string * thm) list
  6106   PureThy.all_thms_of: theory -> (string * thm) list
  6107 
  6108 * Pure: print_tac now outputs the goal through the trace channel.
  6109 
  6110 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  6111 Reference Toplevel.debug (default false) controls detailed printing
  6112 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  6113 controls execution profiling -- set to 1 for time and 2 for space
  6114 (both increase the runtime).
  6115 
  6116 * Isar session: The initial use of ROOT.ML is now always timed,
  6117 i.e. the log will show the actual process times, in contrast to the
  6118 elapsed wall-clock time that the outer shell wrapper produces.
  6119 
  6120 * Simplifier: improved handling of bound variables (nameless
  6121 representation, avoid allocating new strings).  Simprocs that invoke
  6122 the Simplifier recursively should use Simplifier.inherit_bounds to
  6123 avoid local name clashes.  Failure to do so produces warnings
  6124 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  6125 for further details.
  6126 
  6127 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  6128 bindings for all theorems stored within a given theory; this may help
  6129 in porting non-Isar theories to Isar ones, while keeping ML proof
  6130 scripts for the time being.
  6131 
  6132 * ML operator HTML.with_charset specifies the charset begin used for
  6133 generated HTML files.  For example:
  6134 
  6135   HTML.with_charset "utf-8" use_thy "Hebrew";
  6136   HTML.with_charset "utf-8" use_thy "Chinese";
  6137 
  6138 
  6139 *** System ***
  6140 
  6141 * Allow symlinks to all proper Isabelle executables (Isabelle,
  6142 isabelle, isatool etc.).
  6143 
  6144 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  6145 isatool doc, isatool mkdir, display_drafts etc.).
  6146 
  6147 * isatool usedir: option -f allows specification of the ML file to be
  6148 used by Isabelle; default is ROOT.ML.
  6149 
  6150 * New isatool version outputs the version identifier of the Isabelle
  6151 distribution being used.
  6152 
  6153 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  6154 (containing Boolean satisfiability problems) into Isabelle/HOL
  6155 theories.
  6156 
  6157 
  6158 
  6159 New in Isabelle2004 (April 2004)
  6160 --------------------------------
  6161 
  6162 *** General ***
  6163 
  6164 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  6165   Replaces linorder.ML.
  6166 
  6167 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  6168   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  6169   (\<a>...\<z>), are now considered normal letters, and can therefore
  6170   be used anywhere where an ASCII letter (a...zA...Z) has until
  6171   now. COMPATIBILITY: This obviously changes the parsing of some
  6172   terms, especially where a symbol has been used as a binder, say
  6173   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  6174   as an identifier.  Fix it by inserting a space around former
  6175   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  6176   existing theory and ML files.
  6177 
  6178 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  6179 
  6180 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  6181   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  6182   a normal (but invisible) letter. For multiple letter subscripts repeat
  6183   \<^isub> like this: x\<^isub>1\<^isub>2.
  6184 
  6185 * Pure: There are now sub-/superscripts that can span more than one
  6186   character. Text between \<^bsub> and \<^esub> is set in subscript in
  6187   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  6188   superscript. The new control characters are not identifier parts.
  6189 
  6190 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  6191   content of "..." to the latex file instead of \isacntrl... . The "..."
  6192   may consist of any printable characters excluding the end bracket >.
  6193 
  6194 * Pure: Using new Isar command "finalconsts" (or the ML functions
  6195   Theory.add_finals or Theory.add_finals_i) it is now possible to
  6196   declare constants "final", which prevents their being given a definition
  6197   later.  It is useful for constants whose behaviour is fixed axiomatically
  6198   rather than definitionally, such as the meta-logic connectives.
  6199 
  6200 * Pure: 'instance' now handles general arities with general sorts
  6201   (i.e. intersections of classes),
  6202 
  6203 * Presentation: generated HTML now uses a CSS style sheet to make layout
  6204   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  6205   It can be changed to alter the colors/layout of generated pages.
  6206 
  6207 
  6208 *** Isar ***
  6209 
  6210 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  6211   cut_tac, subgoal_tac and thin_tac:
  6212   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  6213     locales are no longer forced to write Isar proof scripts.
  6214     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  6215     emulations.
  6216   - INCOMPATIBILITY: names of variables to be instantiated may no
  6217     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  6218     This is consistent with the instantiation attribute "where".
  6219 
  6220 * Attributes "where" and "of":
  6221   - Now take type variables of instantiated theorem into account when reading
  6222     the instantiation string.  This fixes a bug that caused instantiated
  6223     theorems to have too special types in some circumstances.
  6224   - "where" permits explicit instantiations of type variables.
  6225 
  6226 * Calculation commands "moreover" and "also" no longer interfere with
  6227   current facts ("this"), admitting arbitrary combinations with "then"
  6228   and derived forms.
  6229 
  6230 * Locales:
  6231   - Goal statements involving the context element "includes" no longer
  6232     generate theorems with internal delta predicates (those ending on
  6233     "_axioms") in the premise.
  6234     Resolve particular premise with <locale>.intro to obtain old form.
  6235   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6236     specification and "includes" elements in goal statement.
  6237   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6238     [intro?] and [elim?] (respectively) by default.
  6239   - Experimental command for instantiation of locales in proof contexts:
  6240         instantiate <label>[<attrs>]: <loc>
  6241     Instantiates locale <loc> and adds all its theorems to the current context
  6242     taking into account their attributes.  Label