NEWS
author huffman
Wed Sep 07 19:24:28 2011 -0700 (2011-09-07)
changeset 44826 1120cba9bce4
parent 44822 2690b6de5021
parent 44820 7798deb6f8fa
child 44845 5e51075cbd97
permissions -rw-r--r--
merged
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in Isabelle2011-1 (October 2011)
     5 ------------------------------------
     6 
     7 *** General ***
     8 
     9 * Improved Isabelle/jEdit Prover IDE (PIDE), which can be invoked as
    10 "isabelle jedit" on the command line.
    11 
    12   - Management of multiple theory files directly from the editor
    13     buffer store -- bypassing the file-system (no requirement to save
    14     files for checking).
    15 
    16   - Markup of formal entities within the text buffer, with semantic
    17     highlighting, tooltips and hyperlinks to jump to defining source
    18     positions.
    19 
    20   - Improved text rendering, with sub/superscripts in the source
    21     buffer (including support for copy/paste wrt. output panel, HTML
    22     theory output and other non-Isabelle text boxes).
    23 
    24   - Refined scheduling of proof checking and printing of results,
    25     based on interactive editor view.  (Note: jEdit folding and
    26     narrowing allows to restrict buffer perspectives explicitly.)
    27 
    28   - Reduced CPU performance requirements, usable on machines with few
    29     cores.
    30 
    31   - Reduced memory requirements due to pruning of unused document
    32     versions (garbage collection).
    33 
    34 See also ~~/src/Tools/jEdit/README.html for further information,
    35 including some remaining limitations.
    36 
    37 * Theory loader: source files are exclusively located via the master
    38 directory of each theory node (where the .thy file itself resides).
    39 The global load path (such as src/HOL/Library) has been discontinued.
    40 Note that the path element ~~ may be used to reference theories in the
    41 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    42 INCOMPATIBILITY.
    43 
    44 * Theory loader: source files are identified by content via SHA1
    45 digests.  Discontinued former path/modtime identification and optional
    46 ISABELLE_FILE_IDENT plugin scripts.
    47 
    48 * Parallelization of nested Isar proofs is subject to
    49 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    50 usedir option -Q.
    51 
    52 * Discontinued support for Poly/ML 5.2, which was the last version
    53 without proper multithreading and TimeLimit implementation.
    54 
    55 * Discontinued old lib/scripts/polyml-platform, which has been
    56 obsolete since Isabelle2009-2.
    57 
    58 * Various optional external tools are referenced more robustly and
    59 uniformly by explicit Isabelle settings as follows:
    60 
    61   ISABELLE_CSDP   (formerly CSDP_EXE)
    62   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    63   ISABELLE_OCAML  (formerly EXEC_OCAML)
    64   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    65   ISABELLE_YAP    (formerly EXEC_YAP)
    66 
    67 Note that automated detection from the file-system or search path has
    68 been discontinued.  INCOMPATIBILITY.
    69 
    70 * Name space: former unsynchronized references are now proper
    71 configuration options, with more conventional names:
    72 
    73   long_names   ~> names_long
    74   short_names  ~> names_short
    75   unique_names ~> names_unique
    76 
    77 Minor INCOMPATIBILITY, need to declare options in context like this:
    78 
    79   declare [[names_unique = false]]
    80 
    81 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    82 that the result needs to be unique, which means fact specifications
    83 may have to be refined after enriching a proof context.
    84 
    85 * Attribute "case_names" has been refined: the assumptions in each case
    86 can be named now by following the case name with [name1 name2 ...].
    87 
    88 * Isabelle/Isar reference manual provides more formal references in
    89 syntax diagrams.
    90 
    91 
    92 *** HOL ***
    93 
    94 * Theory Library/Saturated provides type of numbers with saturated
    95 arithmetic.
    96 
    97 * Classes bot and top require underlying partial order rather than
    98 preorder: uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    99 
   100 * Class complete_lattice: generalized a couple of lemmas from sets;
   101 generalized theorems INF_cong and SUP_cong.  New type classes for
   102 complete boolean algebras and complete linear orders.  Lemmas
   103 Inf_less_iff, less_Sup_iff, INF_less_iff, less_SUP_iff now reside in
   104 class complete_linorder.
   105 
   106 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def,
   107 Sup_fun_def, Inf_apply, Sup_apply.
   108 
   109 Redundant lemmas Inf_singleton, Sup_singleton, Inf_binary, Sup_binary,
   110 INF_eq, SUP_eq, INF_UNIV_range, SUP_UNIV_range, Int_eq_Inter,
   111 INTER_eq_Inter_image, Inter_def, INT_eq, Un_eq_Union,
   112 UNION_eq_Union_image, Union_def, UN_singleton, UN_eq have been
   113 discarded.
   114 
   115 More consistent and comprehensive names:
   116 
   117   INFI_def ~> INF_def
   118   SUPR_def ~> SUP_def
   119   INF_leI ~> INF_lower
   120   INF_leI2 ~> INF_lower2
   121   le_INFI ~> INF_greatest
   122   le_SUPI ~> SUP_upper
   123   le_SUPI2 ~> SUP_upper2
   124   SUP_leI ~> SUP_least
   125   INFI_bool_eq ~> INF_bool_eq
   126   SUPR_bool_eq ~> SUP_bool_eq
   127   INFI_apply ~> INF_apply
   128   SUPR_apply ~> SUP_apply
   129   INTER_def ~> INTER_eq
   130   UNION_def ~> UNION_eq
   131 
   132 INCOMPATIBILITY.
   133 
   134 * Theorem collections ball_simps and bex_simps do not contain theorems
   135 referring to UNION any longer; these have been moved to collection
   136 UN_ball_bex_simps.  INCOMPATIBILITY.
   137 
   138 * Theory Archimedean_Field: floor now is defined as parameter of a
   139 separate type class floor_ceiling.
   140 
   141 * Theory Finite_Set: more coherent development of fold_set locales:
   142 
   143     locale fun_left_comm ~> locale comp_fun_commute
   144     locale fun_left_comm_idem ~> locale comp_fun_idem
   145 
   146 Both use point-free characterization; interpretation proofs may need
   147 adjustment.  INCOMPATIBILITY.
   148 
   149 * Code generation:
   150 
   151   - Theory Library/Code_Char_ord provides native ordering of
   152     characters in the target language.
   153 
   154   - Commands code_module and code_library are legacy, use export_code instead.
   155 
   156   - Method "evaluation" is legacy, use method "eval" instead.
   157 
   158   - Legacy evaluator "SML" is deactivated by default.  May be
   159     reactivated by the following theory command:
   160 
   161       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   162 
   163 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   164 
   165 * Nitpick:
   166   - Added "need" and "total_consts" options.
   167   - Reintroduced "show_skolems" option by popular demand.
   168   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   169     INCOMPATIBILITY.
   170 
   171 * Sledgehammer:
   172   - sledgehammer available_provers ~> sledgehammer supported_provers.
   173     INCOMPATIBILITY.
   174   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   175     TPTP problems (TFF).
   176   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   177     and "max_new_mono_instances" options.
   178   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   179     Proof General menu item. INCOMPATIBILITY.
   180 
   181 * Metis:
   182   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   183   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   184 
   185 * Command 'try':
   186   - Renamed 'try_methods' and added "simp:", "intro:", "dest:", and
   187     "elim:" options. INCOMPATIBILITY.
   188   - Introduced 'tryƄ that not only runs 'try_methods' but also
   189     'solve_direct', 'sledgehammer', 'quickcheck', and 'nitpick'.
   190 
   191 * Quickcheck:
   192 
   193   - Added "eval" option to evaluate terms for the found counterexample
   194     (currently only supported by the default (exhaustive) tester).
   195 
   196   - Added post-processing of terms to obtain readable counterexamples
   197     (currently only supported by the default (exhaustive) tester).
   198 
   199   - New counterexample generator quickcheck[narrowing] enables
   200     narrowing-based testing.  Requires the Glasgow Haskell compiler
   201     with its installation location defined in the Isabelle settings
   202     environment as ISABELLE_GHC.
   203 
   204   - Removed quickcheck tester "SML" based on the SML code generator
   205     (formly in HOL/Library).
   206 
   207 * Function package: discontinued option "tailrec".
   208 INCOMPATIBILITY. Use 'partial_function' instead.
   209 
   210 * Session HOL-Probability:
   211   - Caratheodory's extension lemma is now proved for ring_of_sets.
   212   - Infinite products of probability measures are now available.
   213   - Use extended reals instead of positive extended
   214     reals. INCOMPATIBILITY.
   215 
   216 * Old 'recdef' package has been moved to theory Library/Old_Recdef,
   217 from where it must be imported explicitly.  INCOMPATIBILITY.
   218 
   219 * Well-founded recursion combinator "wfrec" has been moved to theory
   220 Library/Wfrec. INCOMPATIBILITY.
   221 
   222 * Theory Library/Nat_Infinity has been renamed to
   223 Library/Extended_Nat, with name changes of the following types and
   224 constants:
   225 
   226   type inat   ~> type enat
   227   Fin         ~> enat
   228   Infty       ~> infinity (overloaded)
   229   iSuc        ~> eSuc
   230   the_Fin     ~> the_enat
   231 
   232 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   233 been renamed accordingly.
   234 
   235 * Theory Limits: Type "'a net" has been renamed to "'a filter", in
   236 accordance with standard mathematical terminology. INCOMPATIBILITY.
   237 
   238 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   239 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   240 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   241 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   242 changed to match. Definition theorems for overloaded constants now use
   243 the standard "foo_vec_def" naming scheme. A few other theorems have
   244 been renamed as follows (INCOMPATIBILITY):
   245 
   246   Cart_eq          ~> vec_eq_iff
   247   dist_nth_le_cart ~> dist_vec_nth_le
   248   tendsto_vector   ~> vec_tendstoI
   249   Cauchy_vector    ~> vec_CauchyI
   250 
   251 * Session Multivariate_Analysis: Several duplicate theorems have been
   252 removed, and other theorems have been renamed or replaced with more
   253 general versions. INCOMPATIBILITY.
   254 
   255   finite_choice ~> finite_set_choice
   256   eventually_conjI ~> eventually_conj
   257   eventually_and ~> eventually_conj_iff
   258   eventually_false ~> eventually_False
   259   setsum_norm ~> norm_setsum
   260   Lim_ident_at ~> LIM_ident
   261   Lim_const ~> tendsto_const
   262   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   263   Lim_neg ~> tendsto_minus
   264   Lim_add ~> tendsto_add
   265   Lim_sub ~> tendsto_diff
   266   Lim_mul ~> tendsto_scaleR
   267   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   268   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   269   Lim_linear ~> bounded_linear.tendsto
   270   Lim_component ~> tendsto_euclidean_component
   271   Lim_component_cart ~> tendsto_vec_nth
   272   Lim_inner ~> tendsto_inner [OF tendsto_const]
   273   dot_lsum ~> inner_setsum_left
   274   dot_rsum ~> inner_setsum_right
   275   continuous_cmul ~> continuous_scaleR [OF continuous_const]
   276   continuous_neg ~> continuous_minus
   277   continuous_sub ~> continuous_diff
   278   continuous_vmul ~> continuous_scaleR [OF _ continuous_const]
   279   continuous_mul ~> continuous_scaleR
   280   continuous_inv ~> continuous_inverse
   281   continuous_at_within_inv ~> continuous_at_within_inverse
   282   continuous_at_inv ~> continuous_at_inverse
   283   continuous_at_norm ~> continuous_norm [OF continuous_at_id]
   284   continuous_at_infnorm ~> continuous_infnorm [OF continuous_at_id]
   285   continuous_at_component ~> continuous_component [OF continuous_at_id]
   286   continuous_on_neg ~> continuous_on_minus
   287   continuous_on_sub ~> continuous_on_diff
   288   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   289   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   290   continuous_on_mul ~> continuous_on_scaleR
   291   continuous_on_mul_real ~> continuous_on_mult
   292   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   293   continuous_on_norm ~> continuous_on_norm [OF continuous_on_id]
   294   continuous_on_inverse ~> continuous_on_inv
   295   uniformly_continuous_on_neg ~> uniformly_continuous_on_minus
   296   uniformly_continuous_on_sub ~> uniformly_continuous_on_diff
   297   subset_interior ~> interior_mono
   298   subset_closure ~> closure_mono
   299   closure_univ ~> closure_UNIV
   300   real_arch_lt ~> reals_Archimedean2
   301   real_arch ~> reals_Archimedean3
   302   real_abs_norm ~> abs_norm_cancel
   303   real_abs_sub_norm ~> norm_triangle_ineq3
   304   norm_cauchy_schwarz_abs ~> Cauchy_Schwarz_ineq2
   305 
   306 * Theory Complex_Main: The locale interpretations for the
   307 bounded_linear and bounded_bilinear locales have been removed, in
   308 order to reduce the number of duplicate lemmas. Users must use the
   309 original names for distributivity theorems, potential INCOMPATIBILITY.
   310 
   311   divide.add ~> add_divide_distrib
   312   divide.diff ~> diff_divide_distrib
   313   divide.setsum ~> setsum_divide_distrib
   314   mult.add_right ~> right_distrib
   315   mult.diff_right ~> right_diff_distrib
   316   mult_right.setsum ~> setsum_right_distrib
   317   mult_left.diff ~> left_diff_distrib
   318 
   319 * Theory Complex_Main: Several redundant theorems have been removed or
   320 replaced by more general versions. INCOMPATIBILITY.
   321 
   322   real_of_int_real_of_nat ~> real_of_int_of_nat_eq
   323   real_0_le_divide_iff ~> zero_le_divide_iff
   324   realpow_two_disj ~> power2_eq_iff
   325   real_squared_diff_one_factored ~> square_diff_one_factored
   326   realpow_two_diff ~> square_diff_square_factored
   327   reals_complete2 ~> complete_real
   328   real_sum_squared_expand ~> power2_sum
   329   exp_ln_eq ~> ln_unique
   330   expi_add ~> exp_add
   331   expi_zero ~> exp_zero
   332   lemma_DERIV_subst ~> DERIV_cong
   333   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   334   LIMSEQ_const ~> tendsto_const
   335   LIMSEQ_norm ~> tendsto_norm
   336   LIMSEQ_add ~> tendsto_add
   337   LIMSEQ_minus ~> tendsto_minus
   338   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   339   LIMSEQ_diff ~> tendsto_diff
   340   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   341   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   342   LIMSEQ_mult ~> tendsto_mult
   343   LIMSEQ_inverse ~> tendsto_inverse
   344   LIMSEQ_divide ~> tendsto_divide
   345   LIMSEQ_pow ~> tendsto_power
   346   LIMSEQ_setsum ~> tendsto_setsum
   347   LIMSEQ_setprod ~> tendsto_setprod
   348   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   349   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   350   LIMSEQ_imp_rabs ~> tendsto_rabs
   351   LIMSEQ_add_minus ~> tendsto_add [OF _ tendsto_minus]
   352   LIMSEQ_add_const ~> tendsto_add [OF _ tendsto_const]
   353   LIMSEQ_diff_const ~> tendsto_diff [OF _ tendsto_const]
   354   LIMSEQ_Complex ~> tendsto_Complex
   355   LIM_ident ~> tendsto_ident_at
   356   LIM_const ~> tendsto_const
   357   LIM_add ~> tendsto_add
   358   LIM_add_zero ~> tendsto_add_zero
   359   LIM_minus ~> tendsto_minus
   360   LIM_diff ~> tendsto_diff
   361   LIM_norm ~> tendsto_norm
   362   LIM_norm_zero ~> tendsto_norm_zero
   363   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   364   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   365   LIM_rabs ~> tendsto_rabs
   366   LIM_rabs_zero ~> tendsto_rabs_zero
   367   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   368   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   369   LIM_compose ~> tendsto_compose
   370   LIM_mult ~> tendsto_mult
   371   LIM_scaleR ~> tendsto_scaleR
   372   LIM_of_real ~> tendsto_of_real
   373   LIM_power ~> tendsto_power
   374   LIM_inverse ~> tendsto_inverse
   375   LIM_sgn ~> tendsto_sgn
   376   isCont_LIM_compose ~> isCont_tendsto_compose
   377   bounded_linear.LIM ~> bounded_linear.tendsto
   378   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   379   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   380   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   381   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   382   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   383   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   384 
   385 
   386 *** Document preparation ***
   387 
   388 * Localized \isabellestyle switch can be used within blocks or groups
   389 like this:
   390 
   391   \isabellestyle{it}  %preferred default
   392   {\isabellestylett @{text "typewriter stuff"}}
   393 
   394 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   395 isar-ref manual, both for description and actual application of the
   396 same.
   397 
   398 * Antiquotation @{value} evaluates the given term and presents its
   399 result.
   400 
   401 * Antiquotations: term style "isub" provides ad-hoc conversion of
   402 variables x1, y23 into subscripted form x\<^isub>1,
   403 y\<^isub>2\<^isub>3.
   404 
   405 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   406 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   407 
   408 * Discontinued special treatment of hard tabulators, which are better
   409 avoided in the first place (no universally agreed standard expansion).
   410 Implicit tab-width is now 1.
   411 
   412 
   413 *** ML ***
   414 
   415 * The inner syntax of sort/type/term/prop supports inlined YXML
   416 representations within quoted string tokens.  By encoding logical
   417 entities via Term_XML (in ML or Scala) concrete syntax can be
   418 bypassed, which is particularly useful for producing bits of text
   419 under external program control.
   420 
   421 * Antiquotations for ML and document preparation are managed as theory
   422 data, which requires explicit setup.
   423 
   424 * Isabelle_Process.is_active allows tools to check if the official
   425 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   426 (better known as Proof General).
   427 
   428 * Structure Proof_Context follows standard naming scheme.  Old
   429 ProofContext is still available for some time as legacy alias.
   430 
   431 * Structure Timing provides various operations for timing; supersedes
   432 former start_timing/end_timing etc.
   433 
   434 * Path.print is the official way to show file-system paths to users
   435 (including quotes etc.).
   436 
   437 * Inner syntax: identifiers in parse trees of generic categories
   438 "logic", "aprop", "idt" etc. carry position information (disguised as
   439 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   440 translations that choke on unexpected type constraints.  Positions can
   441 be stripped in ML translations via Syntax.strip_positions /
   442 Syntax.strip_positions_ast, or via the syntax constant
   443 "_strip_positions" within parse trees.  As last resort, positions can
   444 be disabled via the configuration option Syntax.positions, which is
   445 called "syntax_positions" in Isar attribute syntax.
   446 
   447 * Discontinued special status of various ML structures that contribute
   448 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   449 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   450 refer directly to Ast.Constant, Lexicon.is_identifier,
   451 Syntax_Trans.mk_binder_tr etc.
   452 
   453 * Typed print translation: discontinued show_sorts argument, which is
   454 already available via context of "advanced" translation.
   455 
   456 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   457 goal states; body tactic needs to address all subgoals uniformly.
   458 
   459 * Slightly more special eq_list/eq_set, with shortcut involving
   460 pointer equality (assumes that eq relation is reflexive).
   461 
   462 * Classical tactics use proper Proof.context instead of historic types
   463 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   464 operate directly on Proof.context.  Raw type claset retains its use as
   465 snapshot of the classical context, which can be recovered via
   466 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   467 INCOMPATIBILITY, classical tactics and derived proof methods require
   468 proper Proof.context.
   469 
   470 
   471 *** System ***
   472 
   473 * Scala layer provides JVM method invocation service for static
   474 methods of type (String)String, see Invoke_Scala.method in ML.  For
   475 example:
   476 
   477   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   478 
   479 Togeter with YXML.string_of_body/parse_body and XML.Encode/Decode this
   480 allows to pass structured values between ML and Scala.
   481 
   482 * The IsabelleText fonts includes some further glyphs to support the
   483 Prover IDE.  Potential INCOMPATIBILITY: users who happen to have
   484 installed a local copy (which is normally *not* required) need to
   485 delete or update it from ~~/lib/fonts/.
   486 
   487 
   488 New in Isabelle2011 (January 2011)
   489 ----------------------------------
   490 
   491 *** General ***
   492 
   493 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   494 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   495 useful tooltips and hyperlinks produced from its static analysis.  The
   496 bundled component provides an executable Isabelle tool that can be run
   497 like this:
   498 
   499   Isabelle2011/bin/isabelle jedit
   500 
   501 * Significantly improved Isabelle/Isar implementation manual.
   502 
   503 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   504 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   505 while the default heap location within that directory lacks that extra
   506 suffix.  This isolates multiple Isabelle installations from each
   507 other, avoiding problems with old settings in new versions.
   508 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   509 
   510 * Source files are always encoded as UTF-8, instead of old-fashioned
   511 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   512 the following package declarations:
   513 
   514   \usepackage[utf8]{inputenc}
   515   \usepackage{textcomp}
   516 
   517 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   518 a Unicode character is treated as a single symbol, not a sequence of
   519 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   520 contain symbols without further backslash escapes, Unicode can now be
   521 used here as well.  Recall that Symbol.explode in ML provides a
   522 consistent view on symbols, while raw explode (or String.explode)
   523 merely give a byte-oriented representation.
   524 
   525 * Theory loader: source files are primarily located via the master
   526 directory of each theory node (where the .thy file itself resides).
   527 The global load path is still partially available as legacy feature.
   528 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   529 explicit paths, relatively to the theory.
   530 
   531 * Special treatment of ML file names has been discontinued.
   532 Historically, optional extensions .ML or .sml were added on demand --
   533 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   534 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   535 
   536 * Various options that affect pretty printing etc. are now properly
   537 handled within the context via configuration options, instead of
   538 unsynchronized references or print modes.  There are both ML Config.T
   539 entities and Isar declaration attributes to access these.
   540 
   541   ML (Config.T)                 Isar (attribute)
   542 
   543   eta_contract                  eta_contract
   544   show_brackets                 show_brackets
   545   show_sorts                    show_sorts
   546   show_types                    show_types
   547   show_question_marks           show_question_marks
   548   show_consts                   show_consts
   549   show_abbrevs                  show_abbrevs
   550 
   551   Syntax.ast_trace              syntax_ast_trace
   552   Syntax.ast_stat               syntax_ast_stat
   553   Syntax.ambiguity_level        syntax_ambiguity_level
   554 
   555   Goal_Display.goals_limit      goals_limit
   556   Goal_Display.show_main_goal   show_main_goal
   557 
   558   Method.rule_trace             rule_trace
   559 
   560   Thy_Output.display            thy_output_display
   561   Thy_Output.quotes             thy_output_quotes
   562   Thy_Output.indent             thy_output_indent
   563   Thy_Output.source             thy_output_source
   564   Thy_Output.break              thy_output_break
   565 
   566 Note that corresponding "..._default" references in ML may only be
   567 changed globally at the ROOT session setup, but *not* within a theory.
   568 The option "show_abbrevs" supersedes the former print mode
   569 "no_abbrevs" with inverted meaning.
   570 
   571 * More systematic naming of some configuration options.
   572 INCOMPATIBILITY.
   573 
   574   trace_simp  ~>  simp_trace
   575   debug_simp  ~>  simp_debug
   576 
   577 * Support for real valued configuration options, using simplistic
   578 floating-point notation that coincides with the inner syntax for
   579 float_token.
   580 
   581 * Support for real valued preferences (with approximative PGIP type):
   582 front-ends need to accept "pgint" values in float notation.
   583 INCOMPATIBILITY.
   584 
   585 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   586 DejaVu Sans.
   587 
   588 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   589 
   590 
   591 *** Pure ***
   592 
   593 * Command 'type_synonym' (with single argument) replaces somewhat
   594 outdated 'types', which is still available as legacy feature for some
   595 time.
   596 
   597 * Command 'nonterminal' (with 'and' separated list of arguments)
   598 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   599 
   600 * Command 'notepad' replaces former 'example_proof' for
   601 experimentation in Isar without any result.  INCOMPATIBILITY.
   602 
   603 * Locale interpretation commands 'interpret' and 'sublocale' accept
   604 lists of equations to map definitions in a locale to appropriate
   605 entities in the context of the interpretation.  The 'interpretation'
   606 command already provided this functionality.
   607 
   608 * Diagnostic command 'print_dependencies' prints the locale instances
   609 that would be activated if the specified expression was interpreted in
   610 the current context.  Variant "print_dependencies!" assumes a context
   611 without interpretations.
   612 
   613 * Diagnostic command 'print_interps' prints interpretations in proofs
   614 in addition to interpretations in theories.
   615 
   616 * Discontinued obsolete 'global' and 'local' commands to manipulate
   617 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   618 Sign.root_path and Sign.local_path may be applied directly where this
   619 feature is still required for historical reasons.
   620 
   621 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   622 'definition' instead.
   623 
   624 * The "prems" fact, which refers to the accidental collection of
   625 foundational premises in the context, is now explicitly marked as
   626 legacy feature and will be discontinued soon.  Consider using "assms"
   627 of the head statement or reference facts by explicit names.
   628 
   629 * Document antiquotations @{class} and @{type} print classes and type
   630 constructors.
   631 
   632 * Document antiquotation @{file} checks file/directory entries within
   633 the local file system.
   634 
   635 
   636 *** HOL ***
   637 
   638 * Coercive subtyping: functions can be declared as coercions and type
   639 inference will add them as necessary upon input of a term.  Theory
   640 Complex_Main declares real :: nat => real and real :: int => real as
   641 coercions. A coercion function f is declared like this:
   642 
   643   declare [[coercion f]]
   644 
   645 To lift coercions through type constructors (e.g. from nat => real to
   646 nat list => real list), map functions can be declared, e.g.
   647 
   648   declare [[coercion_map map]]
   649 
   650 Currently coercion inference is activated only in theories including
   651 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   652 the configuration option "coercion_enabled", e.g. it can be enabled in
   653 other theories like this:
   654 
   655   declare [[coercion_enabled]]
   656 
   657 * Command 'partial_function' provides basic support for recursive
   658 function definitions over complete partial orders.  Concrete instances
   659 are provided for i) the option type, ii) tail recursion on arbitrary
   660 types, and iii) the heap monad of Imperative_HOL.  See
   661 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   662 for examples.
   663 
   664 * Function package: f.psimps rules are no longer implicitly declared
   665 as [simp].  INCOMPATIBILITY.
   666 
   667 * Datatype package: theorems generated for executable equality (class
   668 "eq") carry proper names and are treated as default code equations.
   669 
   670 * Inductive package: now offers command 'inductive_simps' to
   671 automatically derive instantiated and simplified equations for
   672 inductive predicates, similar to 'inductive_cases'.
   673 
   674 * Command 'enriched_type' allows to register properties of the
   675 functorial structure of types.
   676 
   677 * Improved infrastructure for term evaluation using code generator
   678 techniques, in particular static evaluation conversions.
   679 
   680 * Code generator: Scala (2.8 or higher) has been added to the target
   681 languages.
   682 
   683 * Code generator: globbing constant expressions "*" and "Theory.*"
   684 have been replaced by the more idiomatic "_" and "Theory._".
   685 INCOMPATIBILITY.
   686 
   687 * Code generator: export_code without explicit file declaration prints
   688 to standard output.  INCOMPATIBILITY.
   689 
   690 * Code generator: do not print function definitions for case
   691 combinators any longer.
   692 
   693 * Code generator: simplification with rules determined with
   694 src/Tools/Code/code_simp.ML and method "code_simp".
   695 
   696 * Code generator for records: more idiomatic representation of record
   697 types.  Warning: records are not covered by ancient SML code
   698 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   699 rep_datatype declaration helps to succeed then:
   700 
   701   record 'a foo = ...
   702   ...
   703   rep_datatype foo_ext ...
   704 
   705 * Records: logical foundation type for records does not carry a
   706 '_type' suffix any longer (obsolete due to authentic syntax).
   707 INCOMPATIBILITY.
   708 
   709 * Quickcheck now by default uses exhaustive testing instead of random
   710 testing.  Random testing can be invoked by "quickcheck [random]",
   711 exhaustive testing by "quickcheck [exhaustive]".
   712 
   713 * Quickcheck instantiates polymorphic types with small finite
   714 datatypes by default. This enables a simple execution mechanism to
   715 handle quantifiers and function equality over the finite datatypes.
   716 
   717 * Quickcheck random generator has been renamed from "code" to
   718 "random".  INCOMPATIBILITY.
   719 
   720 * Quickcheck now has a configurable time limit which is set to 30
   721 seconds by default. This can be changed by adding [timeout = n] to the
   722 quickcheck command. The time limit for Auto Quickcheck is still set
   723 independently.
   724 
   725 * Quickcheck in locales considers interpretations of that locale for
   726 counter example search.
   727 
   728 * Sledgehammer:
   729   - Added "smt" and "remote_smt" provers based on the "smt" proof
   730     method. See the Sledgehammer manual for details ("isabelle doc
   731     sledgehammer").
   732   - Renamed commands:
   733     sledgehammer atp_info ~> sledgehammer running_provers
   734     sledgehammer atp_kill ~> sledgehammer kill_provers
   735     sledgehammer available_atps ~> sledgehammer available_provers
   736     INCOMPATIBILITY.
   737   - Renamed options:
   738     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   739     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   740     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   741     (and "ms" and "min" are no longer supported)
   742     INCOMPATIBILITY.
   743 
   744 * Nitpick:
   745   - Renamed options:
   746     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   747     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   748     INCOMPATIBILITY.
   749   - Added support for partial quotient types.
   750   - Added local versions of the "Nitpick.register_xxx" functions.
   751   - Added "whack" option.
   752   - Allow registration of quotient types as codatatypes.
   753   - Improved "merge_type_vars" option to merge more types.
   754   - Removed unsound "fast_descrs" option.
   755   - Added custom symmetry breaking for datatypes, making it possible to reach
   756     higher cardinalities.
   757   - Prevent the expansion of too large definitions.
   758 
   759 * Proof methods "metis" and "meson" now have configuration options
   760 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   761 to diagnose these tools. E.g.
   762 
   763     using [[metis_trace = true]]
   764 
   765 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   766 manually as command 'solve_direct'.
   767 
   768 * The default SMT solver Z3 must be enabled explicitly (due to
   769 licensing issues) by setting the environment variable
   770 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   771 commercial applications, the SMT solver CVC3 is provided as fall-back;
   772 changing the SMT solver is done via the configuration option
   773 "smt_solver".
   774 
   775 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   776 i.e. "remote_cvc3" and "remote_z3".
   777 
   778 * Added basic SMT support for datatypes, records, and typedefs using
   779 the oracle mode (no proofs).  Direct support of pairs has been dropped
   780 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   781 support for a similar behavior).  Minor INCOMPATIBILITY.
   782 
   783 * Changed SMT configuration options:
   784   - Renamed:
   785     z3_proofs ~> smt_oracle (with inverted meaning)
   786     z3_trace_assms ~> smt_trace_used_facts
   787     INCOMPATIBILITY.
   788   - Added:
   789     smt_verbose
   790     smt_random_seed
   791     smt_datatypes
   792     smt_infer_triggers
   793     smt_monomorph_limit
   794     cvc3_options
   795     remote_cvc3_options
   796     remote_z3_options
   797     yices_options
   798 
   799 * Boogie output files (.b2i files) need to be declared in the theory
   800 header.
   801 
   802 * Simplification procedure "list_to_set_comprehension" rewrites list
   803 comprehensions applied to List.set to set comprehensions.  Occasional
   804 INCOMPATIBILITY, may be deactivated like this:
   805 
   806   declare [[simproc del: list_to_set_comprehension]]
   807 
   808 * Removed old version of primrec package.  INCOMPATIBILITY.
   809 
   810 * Removed simplifier congruence rule of "prod_case", as has for long
   811 been the case with "split".  INCOMPATIBILITY.
   812 
   813 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   814 
   815 * Removed [split_format ... and ... and ...] version of
   816 [split_format].  Potential INCOMPATIBILITY.
   817 
   818 * Predicate "sorted" now defined inductively, with nice induction
   819 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   820 
   821 * Constant "contents" renamed to "the_elem", to free the generic name
   822 contents for other uses.  INCOMPATIBILITY.
   823 
   824 * Renamed class eq and constant eq (for code generation) to class
   825 equal and constant equal, plus renaming of related facts and various
   826 tuning.  INCOMPATIBILITY.
   827 
   828 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   829 
   830 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   831 INCOMPATIBILITY.
   832 
   833 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   834 avoid confusion with finite sets.  INCOMPATIBILITY.
   835 
   836 * Abandoned locales equiv, congruent and congruent2 for equivalence
   837 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   838 for congruent(2)).
   839 
   840 * Some previously unqualified names have been qualified:
   841 
   842   types
   843     bool ~> HOL.bool
   844     nat ~> Nat.nat
   845 
   846   constants
   847     Trueprop ~> HOL.Trueprop
   848     True ~> HOL.True
   849     False ~> HOL.False
   850     op & ~> HOL.conj
   851     op | ~> HOL.disj
   852     op --> ~> HOL.implies
   853     op = ~> HOL.eq
   854     Not ~> HOL.Not
   855     The ~> HOL.The
   856     All ~> HOL.All
   857     Ex ~> HOL.Ex
   858     Ex1 ~> HOL.Ex1
   859     Let ~> HOL.Let
   860     If ~> HOL.If
   861     Ball ~> Set.Ball
   862     Bex ~> Set.Bex
   863     Suc ~> Nat.Suc
   864     Pair ~> Product_Type.Pair
   865     fst ~> Product_Type.fst
   866     snd ~> Product_Type.snd
   867     curry ~> Product_Type.curry
   868     op : ~> Set.member
   869     Collect ~> Set.Collect
   870 
   871 INCOMPATIBILITY.
   872 
   873 * More canonical naming convention for some fundamental definitions:
   874 
   875     bot_bool_eq ~> bot_bool_def
   876     top_bool_eq ~> top_bool_def
   877     inf_bool_eq ~> inf_bool_def
   878     sup_bool_eq ~> sup_bool_def
   879     bot_fun_eq  ~> bot_fun_def
   880     top_fun_eq  ~> top_fun_def
   881     inf_fun_eq  ~> inf_fun_def
   882     sup_fun_eq  ~> sup_fun_def
   883 
   884 INCOMPATIBILITY.
   885 
   886 * More stylized fact names:
   887 
   888   expand_fun_eq ~> fun_eq_iff
   889   expand_set_eq ~> set_eq_iff
   890   set_ext       ~> set_eqI
   891   nat_number    ~> eval_nat_numeral
   892 
   893 INCOMPATIBILITY.
   894 
   895 * Refactoring of code-generation specific operations in theory List:
   896 
   897   constants
   898     null ~> List.null
   899 
   900   facts
   901     mem_iff ~> member_def
   902     null_empty ~> null_def
   903 
   904 INCOMPATIBILITY.  Note that these were not supposed to be used
   905 regularly unless for striking reasons; their main purpose was code
   906 generation.
   907 
   908 Various operations from the Haskell prelude are used for generating
   909 Haskell code.
   910 
   911 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   912 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   913 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   914 
   915 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   916 "*" and "+" respectively.  INCOMPATIBILITY.
   917 
   918 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   919 "Sum_Type.Plus" instead.
   920 
   921 * Constant "split" has been merged with constant "prod_case"; names of
   922 ML functions, facts etc. involving split have been retained so far,
   923 though.  INCOMPATIBILITY.
   924 
   925 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   926 instead.  INCOMPATIBILITY.
   927 
   928 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   929 INCOMPATIBILITY.
   930 
   931 * Former theory Library/Enum is now part of the HOL-Main image.
   932 INCOMPATIBILITY: all constants of the Enum theory now have to be
   933 referred to by its qualified name.
   934 
   935   enum    ~>  Enum.enum
   936   nlists  ~>  Enum.nlists
   937   product ~>  Enum.product
   938 
   939 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   940 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   941 INCOMPATIBILITY.
   942 
   943 * Theory Library/SetsAndFunctions has been split into
   944 Library/Function_Algebras and Library/Set_Algebras; canonical names
   945 for instance definitions for functions; various improvements.
   946 INCOMPATIBILITY.
   947 
   948 * Theory Library/Multiset provides stable quicksort implementation of
   949 sort_key.
   950 
   951 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   952 INCOMPATIBILITY.
   953 
   954 * Session Multivariate_Analysis: introduced a type class for euclidean
   955 space.  Most theorems are now stated in terms of euclidean spaces
   956 instead of finite cartesian products.
   957 
   958   types
   959     real ^ 'n ~>  'a::real_vector
   960               ~>  'a::euclidean_space
   961               ~>  'a::ordered_euclidean_space
   962         (depends on your needs)
   963 
   964   constants
   965      _ $ _        ~> _ $$ _
   966      \<chi> x. _  ~> \<chi>\<chi> x. _
   967      CARD('n)     ~> DIM('a)
   968 
   969 Also note that the indices are now natural numbers and not from some
   970 finite type. Finite cartesian products of euclidean spaces, products
   971 of euclidean spaces the real and complex numbers are instantiated to
   972 be euclidean_spaces.  INCOMPATIBILITY.
   973 
   974 * Session Probability: introduced pextreal as positive extended real
   975 numbers.  Use pextreal as value for measures.  Introduce the
   976 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   977 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   978 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   979 
   980 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   981 INCOMPATIBILITY.
   982 
   983 * Session SPARK (with image HOL-SPARK) provides commands to load and
   984 prove verification conditions generated by the SPARK Ada program
   985 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   986 
   987 
   988 *** HOL-Algebra ***
   989 
   990 * Theorems for additive ring operations (locale abelian_monoid and
   991 descendants) are generated by interpretation from their multiplicative
   992 counterparts.  Names (in particular theorem names) have the mandatory
   993 qualifier 'add'.  Previous theorem names are redeclared for
   994 compatibility.
   995 
   996 * Structure "int_ring" is now an abbreviation (previously a
   997 definition).  This fits more natural with advanced interpretations.
   998 
   999 
  1000 *** HOLCF ***
  1001 
  1002 * The domain package now runs in definitional mode by default: The
  1003 former command 'new_domain' is now called 'domain'.  To use the domain
  1004 package in its original axiomatic mode, use 'domain (unsafe)'.
  1005 INCOMPATIBILITY.
  1006 
  1007 * The new class "domain" is now the default sort.  Class "predomain"
  1008 is an unpointed version of "domain". Theories can be updated by
  1009 replacing sort annotations as shown below.  INCOMPATIBILITY.
  1010 
  1011   'a::type ~> 'a::countable
  1012   'a::cpo  ~> 'a::predomain
  1013   'a::pcpo ~> 'a::domain
  1014 
  1015 * The old type class "rep" has been superseded by class "domain".
  1016 Accordingly, users of the definitional package must remove any
  1017 "default_sort rep" declarations.  INCOMPATIBILITY.
  1018 
  1019 * The domain package (definitional mode) now supports unpointed
  1020 predomain argument types, as long as they are marked 'lazy'. (Strict
  1021 arguments must be in class "domain".) For example, the following
  1022 domain definition now works:
  1023 
  1024   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
  1025 
  1026 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
  1027 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
  1028 'a option, and 'a list.  Additionally, it configures fixrec and the
  1029 domain package to work with these types.  For example:
  1030 
  1031   fixrec isInl :: "('a + 'b) u -> tr"
  1032     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
  1033 
  1034   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
  1035 
  1036 * The "(permissive)" option of fixrec has been replaced with a
  1037 per-equation "(unchecked)" option. See
  1038 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
  1039 
  1040 * The "bifinite" class no longer fixes a constant "approx"; the class
  1041 now just asserts that such a function exists.  INCOMPATIBILITY.
  1042 
  1043 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
  1044 defines an embedding of type 'a defl into udom by default; instances
  1045 of "bifinite" and "domain" classes are available in
  1046 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
  1047 
  1048 * The syntax "REP('a)" has been replaced with "DEFL('a)".
  1049 
  1050 * The predicate "directed" has been removed.  INCOMPATIBILITY.
  1051 
  1052 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
  1053 
  1054 * The function "cprod_map" has been renamed to "prod_map".
  1055 INCOMPATIBILITY.
  1056 
  1057 * The monadic bind operator on each powerdomain has new binder syntax
  1058 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
  1059 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
  1060 
  1061 * The infix syntax for binary union on each powerdomain has changed
  1062 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
  1063 syntax.  INCOMPATIBILITY.
  1064 
  1065 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
  1066 still supported as an input translation.
  1067 
  1068 * Renamed some theorems (the original names are also still available).
  1069 
  1070   expand_fun_below   ~> fun_below_iff
  1071   below_fun_ext      ~> fun_belowI
  1072   expand_cfun_eq     ~> cfun_eq_iff
  1073   ext_cfun           ~> cfun_eqI
  1074   expand_cfun_below  ~> cfun_below_iff
  1075   below_cfun_ext     ~> cfun_belowI
  1076   cont2cont_Rep_CFun ~> cont2cont_APP
  1077 
  1078 * The Abs and Rep functions for various types have changed names.
  1079 Related theorem names have also changed to match. INCOMPATIBILITY.
  1080 
  1081   Rep_CFun  ~> Rep_cfun
  1082   Abs_CFun  ~> Abs_cfun
  1083   Rep_Sprod ~> Rep_sprod
  1084   Abs_Sprod ~> Abs_sprod
  1085   Rep_Ssum  ~> Rep_ssum
  1086   Abs_Ssum  ~> Abs_ssum
  1087 
  1088 * Lemmas with names of the form *_defined_iff or *_strict_iff have
  1089 been renamed to *_bottom_iff.  INCOMPATIBILITY.
  1090 
  1091 * Various changes to bisimulation/coinduction with domain package:
  1092 
  1093   - Definitions of "bisim" constants no longer mention definedness.
  1094   - With mutual recursion, "bisim" predicate is now curried.
  1095   - With mutual recursion, each type gets a separate coind theorem.
  1096   - Variable names in bisim_def and coinduct rules have changed.
  1097 
  1098 INCOMPATIBILITY.
  1099 
  1100 * Case combinators generated by the domain package for type "foo" are
  1101 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1102 
  1103 * Several theorems have been renamed to more accurately reflect the
  1104 names of constants and types involved.  INCOMPATIBILITY.
  1105 
  1106   thelub_const    ~> lub_const
  1107   lub_const       ~> is_lub_const
  1108   thelubI         ~> lub_eqI
  1109   is_lub_lub      ~> is_lubD2
  1110   lubI            ~> is_lub_lub
  1111   unique_lub      ~> is_lub_unique
  1112   is_ub_lub       ~> is_lub_rangeD1
  1113   lub_bin_chain   ~> is_lub_bin_chain
  1114   lub_fun         ~> is_lub_fun
  1115   thelub_fun      ~> lub_fun
  1116   thelub_cfun     ~> lub_cfun
  1117   thelub_Pair     ~> lub_Pair
  1118   lub_cprod       ~> is_lub_prod
  1119   thelub_cprod    ~> lub_prod
  1120   minimal_cprod   ~> minimal_prod
  1121   inst_cprod_pcpo ~> inst_prod_pcpo
  1122   UU_I            ~> bottomI
  1123   compact_UU      ~> compact_bottom
  1124   deflation_UU    ~> deflation_bottom
  1125   finite_deflation_UU ~> finite_deflation_bottom
  1126 
  1127 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1128 
  1129   sq_ord_less_eq_trans ~> below_eq_trans
  1130   sq_ord_eq_less_trans ~> eq_below_trans
  1131   refl_less            ~> below_refl
  1132   trans_less           ~> below_trans
  1133   antisym_less         ~> below_antisym
  1134   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1135   box_less             ~> box_below
  1136   rev_trans_less       ~> rev_below_trans
  1137   not_less2not_eq      ~> not_below2not_eq
  1138   less_UU_iff          ~> below_UU_iff
  1139   flat_less_iff        ~> flat_below_iff
  1140   adm_less             ~> adm_below
  1141   adm_not_less         ~> adm_not_below
  1142   adm_compact_not_less ~> adm_compact_not_below
  1143   less_fun_def         ~> below_fun_def
  1144   expand_fun_less      ~> fun_below_iff
  1145   less_fun_ext         ~> fun_belowI
  1146   less_discr_def       ~> below_discr_def
  1147   discr_less_eq        ~> discr_below_eq
  1148   less_unit_def        ~> below_unit_def
  1149   less_cprod_def       ~> below_prod_def
  1150   prod_lessI           ~> prod_belowI
  1151   Pair_less_iff        ~> Pair_below_iff
  1152   fst_less_iff         ~> fst_below_iff
  1153   snd_less_iff         ~> snd_below_iff
  1154   expand_cfun_less     ~> cfun_below_iff
  1155   less_cfun_ext        ~> cfun_belowI
  1156   injection_less       ~> injection_below
  1157   less_up_def          ~> below_up_def
  1158   not_Iup_less         ~> not_Iup_below
  1159   Iup_less             ~> Iup_below
  1160   up_less              ~> up_below
  1161   Def_inject_less_eq   ~> Def_below_Def
  1162   Def_less_is_eq       ~> Def_below_iff
  1163   spair_less_iff       ~> spair_below_iff
  1164   less_sprod           ~> below_sprod
  1165   spair_less           ~> spair_below
  1166   sfst_less_iff        ~> sfst_below_iff
  1167   ssnd_less_iff        ~> ssnd_below_iff
  1168   fix_least_less       ~> fix_least_below
  1169   dist_less_one        ~> dist_below_one
  1170   less_ONE             ~> below_ONE
  1171   ONE_less_iff         ~> ONE_below_iff
  1172   less_sinlD           ~> below_sinlD
  1173   less_sinrD           ~> below_sinrD
  1174 
  1175 
  1176 *** FOL and ZF ***
  1177 
  1178 * All constant names are now qualified internally and use proper
  1179 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1180 
  1181 
  1182 *** ML ***
  1183 
  1184 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1185 Fail if the argument is false.  Due to inlining the source position of
  1186 failed assertions is included in the error output.
  1187 
  1188 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1189 text is in practice always evaluated with a stable theory checkpoint.
  1190 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1191 
  1192 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1193 the current context, not any accidental theory loader state as before.
  1194 Potential INCOMPATIBILITY, subtle change in semantics.
  1195 
  1196 * Syntax.pretty_priority (default 0) configures the required priority
  1197 of pretty-printed output and thus affects insertion of parentheses.
  1198 
  1199 * Syntax.default_root (default "any") configures the inner syntax
  1200 category (nonterminal symbol) for parsing of terms.
  1201 
  1202 * Former exception Library.UnequalLengths now coincides with
  1203 ListPair.UnequalLengths.
  1204 
  1205 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1206 main functionality is provided by structure Simplifier.
  1207 
  1208 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1209 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1210 almost all situations.
  1211 
  1212 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1213 See implementation manual for further details on exceptions in
  1214 Isabelle/ML.
  1215 
  1216 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1217 meaning.
  1218 
  1219 * Renamed structure PureThy to Pure_Thy and moved most of its
  1220 operations to structure Global_Theory, to emphasize that this is
  1221 rarely-used global-only stuff.
  1222 
  1223 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1224 instead (or tracing for high-volume output).
  1225 
  1226 * Configuration option show_question_marks only affects regular pretty
  1227 printing of types and terms, not raw Term.string_of_vname.
  1228 
  1229 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1230 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1231 @{thms} for most purposes.
  1232 
  1233 * ML structure Unsynchronized is never opened, not even in Isar
  1234 interaction mode as before.  Old Unsynchronized.set etc. have been
  1235 discontinued -- use plain := instead.  This should be *rare* anyway,
  1236 since modern tools always work via official context data, notably
  1237 configuration options.
  1238 
  1239 * Parallel and asynchronous execution requires special care concerning
  1240 interrupts.  Structure Exn provides some convenience functions that
  1241 avoid working directly with raw Interrupt.  User code must not absorb
  1242 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1243 followed by re-raising of the original exception.  Another common
  1244 source of mistakes are "handle _" patterns, which make the meaning of
  1245 the program subject to physical effects of the environment.
  1246 
  1247 
  1248 
  1249 New in Isabelle2009-2 (June 2010)
  1250 ---------------------------------
  1251 
  1252 *** General ***
  1253 
  1254 * Authentic syntax for *all* logical entities (type classes, type
  1255 constructors, term constants): provides simple and robust
  1256 correspondence between formal entities and concrete syntax.  Within
  1257 the parse tree / AST representations, "constants" are decorated by
  1258 their category (class, type, const) and spelled out explicitly with
  1259 their full internal name.
  1260 
  1261 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1262 and translations (translation rules and translation functions in ML).
  1263 Some hints on upgrading:
  1264 
  1265   - Many existing uses of 'syntax' and 'translations' can be replaced
  1266     by more modern 'type_notation', 'notation' and 'abbreviation',
  1267     which are independent of this issue.
  1268 
  1269   - 'translations' require markup within the AST; the term syntax
  1270     provides the following special forms:
  1271 
  1272       CONST c   -- produces syntax version of constant c from context
  1273       XCONST c  -- literally c, checked as constant from context
  1274       c         -- literally c, if declared by 'syntax'
  1275 
  1276     Plain identifiers are treated as AST variables -- occasionally the
  1277     system indicates accidental variables via the error "rhs contains
  1278     extra variables".
  1279 
  1280     Type classes and type constructors are marked according to their
  1281     concrete syntax.  Some old translations rules need to be written
  1282     for the "type" category, using type constructor application
  1283     instead of pseudo-term application of the default category
  1284     "logic".
  1285 
  1286   - 'parse_translation' etc. in ML may use the following
  1287     antiquotations:
  1288 
  1289       @{class_syntax c}   -- type class c within parse tree / AST
  1290       @{term_syntax c}    -- type constructor c within parse tree / AST
  1291       @{const_syntax c}   -- ML version of "CONST c" above
  1292       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1293 
  1294   - Literal types within 'typed_print_translations', i.e. those *not*
  1295     represented as pseudo-terms are represented verbatim.  Use @{class
  1296     c} or @{type_name c} here instead of the above syntax
  1297     antiquotations.
  1298 
  1299 Note that old non-authentic syntax was based on unqualified base
  1300 names, so all of the above "constant" names would coincide.  Recall
  1301 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1302 diagnose syntax problems.
  1303 
  1304 * Type constructors admit general mixfix syntax, not just infix.
  1305 
  1306 * Concrete syntax may be attached to local entities without a proof
  1307 body, too.  This works via regular mixfix annotations for 'fix',
  1308 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1309 similar to the 'notation' command in theory specifications.
  1310 
  1311 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1312 need to specify constant name and syntax separately.  Internal ML
  1313 datatype constructors have been renamed from InfixName to Infix etc.
  1314 Minor INCOMPATIBILITY.
  1315 
  1316 * Schematic theorem statements need to be explicitly markup as such,
  1317 via commands 'schematic_lemma', 'schematic_theorem',
  1318 'schematic_corollary'.  Thus the relevance of the proof is made
  1319 syntactically clear, which impacts performance in a parallel or
  1320 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1321 
  1322 * Use of cumulative prems via "!" in some proof methods has been
  1323 discontinued (old legacy feature).
  1324 
  1325 * References 'trace_simp' and 'debug_simp' have been replaced by
  1326 configuration options stored in the context. Enabling tracing (the
  1327 case of debugging is similar) in proofs works via
  1328 
  1329   using [[trace_simp = true]]
  1330 
  1331 Tracing is then active for all invocations of the simplifier in
  1332 subsequent goal refinement steps. Tracing may also still be enabled or
  1333 disabled via the ProofGeneral settings menu.
  1334 
  1335 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1336 'hide_fact' replace the former 'hide' KIND command.  Minor
  1337 INCOMPATIBILITY.
  1338 
  1339 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1340 more efficient than combinations with -q1 or -q2.
  1341 
  1342 
  1343 *** Pure ***
  1344 
  1345 * Proofterms record type-class reasoning explicitly, using the
  1346 "unconstrain" operation internally.  This eliminates all sort
  1347 constraints from a theorem and proof, introducing explicit
  1348 OFCLASS-premises.  On the proof term level, this operation is
  1349 automatically applied at theorem boundaries, such that closed proofs
  1350 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1351 inspect proof terms.
  1352 
  1353 * Local theory specifications may depend on extra type variables that
  1354 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1355 are added internally.  For example:
  1356 
  1357   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1358 
  1359 * Predicates of locales introduced by classes carry a mandatory
  1360 "class" prefix.  INCOMPATIBILITY.
  1361 
  1362 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1363 
  1364 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1365 'class' instead.
  1366 
  1367 * Command 'code_reflect' allows to incorporate generated ML code into
  1368 runtime environment; replaces immature code_datatype antiquotation.
  1369 INCOMPATIBILITY.
  1370 
  1371 * Code generator: simple concept for abstract datatypes obeying
  1372 invariants.
  1373 
  1374 * Code generator: details of internal data cache have no impact on the
  1375 user space functionality any longer.
  1376 
  1377 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1378 subgoals.  This is more appropriate for interpretations with 'where'.
  1379 INCOMPATIBILITY.
  1380 
  1381 * Command 'example_proof' opens an empty proof body.  This allows to
  1382 experiment with Isar, without producing any persistent result.
  1383 
  1384 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1385 within a local theory context, with explicit checking of the
  1386 constructors involved (in contrast to the raw 'syntax' versions).
  1387 
  1388 * Commands 'types' and 'typedecl' now work within a local theory
  1389 context -- without introducing dependencies on parameters or
  1390 assumptions, which is not possible in Isabelle/Pure.
  1391 
  1392 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1393 within a local theory context.  Minor INCOMPATIBILITY.
  1394 
  1395 
  1396 *** HOL ***
  1397 
  1398 * Command 'typedef' now works within a local theory context -- without
  1399 introducing dependencies on parameters or assumptions, which is not
  1400 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1401 contain multiple interpretations of local typedefs (with different
  1402 non-emptiness proofs), even in a global theory context.
  1403 
  1404 * New package for quotient types.  Commands 'quotient_type' and
  1405 'quotient_definition' may be used for defining types and constants by
  1406 quotient constructions.  An example is the type of integers created by
  1407 quotienting pairs of natural numbers:
  1408 
  1409   fun
  1410     intrel :: "(nat * nat) => (nat * nat) => bool"
  1411   where
  1412     "intrel (x, y) (u, v) = (x + v = u + y)"
  1413 
  1414   quotient_type int = "nat * nat" / intrel
  1415     by (auto simp add: equivp_def expand_fun_eq)
  1416 
  1417   quotient_definition
  1418     "0::int" is "(0::nat, 0::nat)"
  1419 
  1420 The method "lifting" can be used to lift of theorems from the
  1421 underlying "raw" type to the quotient type.  The example
  1422 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1423 construction and provides a reasoning infrastructure for finite sets.
  1424 
  1425 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1426 clash with new theory Quotient in Main HOL.
  1427 
  1428 * Moved the SMT binding into the main HOL session, eliminating
  1429 separate HOL-SMT session.
  1430 
  1431 * List membership infix mem operation is only an input abbreviation.
  1432 INCOMPATIBILITY.
  1433 
  1434 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1435 for future developements; former Library/Word.thy is still present in
  1436 the AFP entry RSAPPS.
  1437 
  1438 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1439 longer shadowed.  INCOMPATIBILITY.
  1440 
  1441 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1442 INCOMPATIBILITY.
  1443 
  1444 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1445 INCOMPATIBILITY.
  1446 
  1447 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1448 instead.  INCOMPATIBILITY.
  1449 
  1450 * Dropped several real-specific versions of lemmas about floor and
  1451 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1452 instead.  INCOMPATIBILITY.
  1453 
  1454   floor_number_of_eq         ~> floor_number_of
  1455   le_floor_eq_number_of      ~> number_of_le_floor
  1456   le_floor_eq_zero           ~> zero_le_floor
  1457   le_floor_eq_one            ~> one_le_floor
  1458   floor_less_eq_number_of    ~> floor_less_number_of
  1459   floor_less_eq_zero         ~> floor_less_zero
  1460   floor_less_eq_one          ~> floor_less_one
  1461   less_floor_eq_number_of    ~> number_of_less_floor
  1462   less_floor_eq_zero         ~> zero_less_floor
  1463   less_floor_eq_one          ~> one_less_floor
  1464   floor_le_eq_number_of      ~> floor_le_number_of
  1465   floor_le_eq_zero           ~> floor_le_zero
  1466   floor_le_eq_one            ~> floor_le_one
  1467   floor_subtract_number_of   ~> floor_diff_number_of
  1468   floor_subtract_one         ~> floor_diff_one
  1469   ceiling_number_of_eq       ~> ceiling_number_of
  1470   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1471   ceiling_le_zero_eq         ~> ceiling_le_zero
  1472   ceiling_le_eq_one          ~> ceiling_le_one
  1473   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1474   less_ceiling_eq_zero       ~> zero_less_ceiling
  1475   less_ceiling_eq_one        ~> one_less_ceiling
  1476   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1477   ceiling_less_eq_zero       ~> ceiling_less_zero
  1478   ceiling_less_eq_one        ~> ceiling_less_one
  1479   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1480   le_ceiling_eq_zero         ~> zero_le_ceiling
  1481   le_ceiling_eq_one          ~> one_le_ceiling
  1482   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1483   ceiling_subtract_one       ~> ceiling_diff_one
  1484 
  1485 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1486 application of the various fold combinators on finite sets.
  1487 
  1488 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1489 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1490 implementation.  INCOMPATIBILTY.
  1491 
  1492 * Theory Library/Coinductive_List has been removed -- superseded by
  1493 AFP/thys/Coinductive.
  1494 
  1495 * Theory PReal, including the type "preal" and related operations, has
  1496 been removed.  INCOMPATIBILITY.
  1497 
  1498 * Real: new development using Cauchy Sequences.
  1499 
  1500 * Split off theory "Big_Operators" containing setsum, setprod,
  1501 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1502 
  1503 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1504 "Int" etc.  INCOMPATIBILITY.
  1505 
  1506 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1507 
  1508 * New set of rules "ac_simps" provides combined assoc / commute
  1509 rewrites for all interpretations of the appropriate generic locales.
  1510 
  1511 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1512 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1513 appropriate and more consistent names suitable for name prefixes
  1514 within the HOL theories.  INCOMPATIBILITY.
  1515 
  1516 * Some generic constants have been put to appropriate theories:
  1517   - less_eq, less: Orderings
  1518   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1519   - inverse, divide: Rings
  1520 INCOMPATIBILITY.
  1521 
  1522 * More consistent naming of type classes involving orderings (and
  1523 lattices):
  1524 
  1525     lower_semilattice                   ~> semilattice_inf
  1526     upper_semilattice                   ~> semilattice_sup
  1527 
  1528     dense_linear_order                  ~> dense_linorder
  1529 
  1530     pordered_ab_group_add               ~> ordered_ab_group_add
  1531     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1532     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1533     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1534     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1535     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1536     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1537     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1538     pordered_comm_ring                  ~> ordered_comm_ring
  1539     pordered_comm_semiring              ~> ordered_comm_semiring
  1540     pordered_ring                       ~> ordered_ring
  1541     pordered_ring_abs                   ~> ordered_ring_abs
  1542     pordered_semiring                   ~> ordered_semiring
  1543 
  1544     ordered_ab_group_add                ~> linordered_ab_group_add
  1545     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1546     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1547     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1548     ordered_field                       ~> linordered_field
  1549     ordered_field_no_lb                 ~> linordered_field_no_lb
  1550     ordered_field_no_ub                 ~> linordered_field_no_ub
  1551     ordered_field_dense_linear_order    ~> dense_linordered_field
  1552     ordered_idom                        ~> linordered_idom
  1553     ordered_ring                        ~> linordered_ring
  1554     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1555     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1556     ordered_ring_strict                 ~> linordered_ring_strict
  1557     ordered_semidom                     ~> linordered_semidom
  1558     ordered_semiring                    ~> linordered_semiring
  1559     ordered_semiring_1                  ~> linordered_semiring_1
  1560     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1561     ordered_semiring_strict             ~> linordered_semiring_strict
  1562 
  1563   The following slightly odd type classes have been moved to a
  1564   separate theory Library/Lattice_Algebras:
  1565 
  1566     lordered_ab_group_add               ~> lattice_ab_group_add
  1567     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1568     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1569     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1570     lordered_ring                       ~> lattice_ring
  1571 
  1572 INCOMPATIBILITY.
  1573 
  1574 * Refined field classes:
  1575   - classes division_ring_inverse_zero, field_inverse_zero,
  1576     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1577     subsumes former division_by_zero class;
  1578   - numerous lemmas have been ported from field to division_ring.
  1579 INCOMPATIBILITY.
  1580 
  1581 * Refined algebra theorem collections:
  1582   - dropped theorem group group_simps, use algebra_simps instead;
  1583   - dropped theorem group ring_simps, use field_simps instead;
  1584   - proper theorem collection field_simps subsumes former theorem
  1585     groups field_eq_simps and field_simps;
  1586   - dropped lemma eq_minus_self_iff which is a duplicate for
  1587     equal_neg_zero.
  1588 INCOMPATIBILITY.
  1589 
  1590 * Theory Finite_Set and List: some lemmas have been generalized from
  1591 sets to lattices:
  1592 
  1593   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1594   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1595   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1596   union_Union_fold_union        ~> sup_Sup_fold_sup
  1597   Inter_fold_inter              ~> Inf_fold_inf
  1598   Union_fold_union              ~> Sup_fold_sup
  1599   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1600   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1601   INTER_fold_inter              ~> INFI_fold_inf
  1602   UNION_fold_union              ~> SUPR_fold_sup
  1603 
  1604 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1605 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1606 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1607 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1608 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1609 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1610 
  1611 * Reorganized theory Multiset: swapped notation of pointwise and
  1612 multiset order:
  1613 
  1614   - pointwise ordering is instance of class order with standard syntax
  1615     <= and <;
  1616   - multiset ordering has syntax <=# and <#; partial order properties
  1617     are provided by means of interpretation with prefix
  1618     multiset_order;
  1619   - less duplication, less historical organization of sections,
  1620     conversion from associations lists to multisets, rudimentary code
  1621     generation;
  1622   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1623     if needed.
  1624 
  1625 Renamed:
  1626 
  1627   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1628   multi_count_ext  ~>  multiset_ext
  1629   diff_union_inverse2  ~>  diff_union_cancelR
  1630 
  1631 INCOMPATIBILITY.
  1632 
  1633 * Theory Permutation: replaced local "remove" by List.remove1.
  1634 
  1635 * Code generation: ML and OCaml code is decorated with signatures.
  1636 
  1637 * Theory List: added transpose.
  1638 
  1639 * Library/Nat_Bijection.thy is a collection of bijective functions
  1640 between nat and other types, which supersedes the older libraries
  1641 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1642 
  1643   Constants:
  1644   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1645   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1646   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1647   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1648   Countable.pair_encode           ~> prod_encode
  1649   NatIso.prod2nat                 ~> prod_encode
  1650   NatIso.nat2prod                 ~> prod_decode
  1651   NatIso.sum2nat                  ~> sum_encode
  1652   NatIso.nat2sum                  ~> sum_decode
  1653   NatIso.list2nat                 ~> list_encode
  1654   NatIso.nat2list                 ~> list_decode
  1655   NatIso.set2nat                  ~> set_encode
  1656   NatIso.nat2set                  ~> set_decode
  1657 
  1658   Lemmas:
  1659   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1660   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1661   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1662   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1663   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1664   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1665   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1666   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1667   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1668   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1669   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1670   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1671   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1672 
  1673 * Sledgehammer:
  1674   - Renamed ATP commands:
  1675     atp_info     ~> sledgehammer running_atps
  1676     atp_kill     ~> sledgehammer kill_atps
  1677     atp_messages ~> sledgehammer messages
  1678     atp_minimize ~> sledgehammer minimize
  1679     print_atps   ~> sledgehammer available_atps
  1680     INCOMPATIBILITY.
  1681   - Added user's manual ("isabelle doc sledgehammer").
  1682   - Added option syntax and "sledgehammer_params" to customize
  1683     Sledgehammer's behavior.  See the manual for details.
  1684   - Modified the Isar proof reconstruction code so that it produces
  1685     direct proofs rather than proofs by contradiction.  (This feature
  1686     is still experimental.)
  1687   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1688     full-typed mode.
  1689   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1690 
  1691 * Nitpick:
  1692   - Added and implemented "binary_ints" and "bits" options.
  1693   - Added "std" option and implemented support for nonstandard models.
  1694   - Added and implemented "finitize" option to improve the precision
  1695     of infinite datatypes based on a monotonicity analysis.
  1696   - Added support for quotient types.
  1697   - Added support for "specification" and "ax_specification"
  1698     constructs.
  1699   - Added support for local definitions (for "function" and
  1700     "termination" proofs).
  1701   - Added support for term postprocessors.
  1702   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1703   - Improved efficiency of "destroy_constrs" optimization.
  1704   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1705     record getters.
  1706   - Fixed soundness bug related to higher-order constructors.
  1707   - Fixed soundness bug when "full_descrs" is enabled.
  1708   - Improved precision of set constructs.
  1709   - Added "atoms" option.
  1710   - Added cache to speed up repeated Kodkod invocations on the same
  1711     problems.
  1712   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1713     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1714     "SAT4J_Light".  INCOMPATIBILITY.
  1715   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1716     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1717   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1718 
  1719 * Method "induct" now takes instantiations of the form t, where t is not
  1720   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1721   If this is not intended, t has to be enclosed in parentheses.
  1722   By default, the equalities generated by definitional instantiations
  1723   are pre-simplified, which may cause parameters of inductive cases
  1724   to disappear, or may even delete some of the inductive cases.
  1725   Use "induct (no_simp)" instead of "induct" to restore the old
  1726   behaviour. The (no_simp) option is also understood by the "cases"
  1727   and "nominal_induct" methods, which now perform pre-simplification, too.
  1728   INCOMPATIBILITY.
  1729 
  1730 
  1731 *** HOLCF ***
  1732 
  1733 * Variable names in lemmas generated by the domain package have
  1734 changed; the naming scheme is now consistent with the HOL datatype
  1735 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1736 
  1737 * The domain package no longer defines the function "foo_copy" for
  1738 recursive domain "foo".  The reach lemma is now stated directly in
  1739 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1740 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1741 
  1742 * Most definedness lemmas generated by the domain package (previously
  1743 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1744 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1745 Proofs that used definedness lemmas as intro rules may break,
  1746 potential INCOMPATIBILITY.
  1747 
  1748 * Induction and casedist rules generated by the domain package now
  1749 declare proper case_names (one called "bottom", and one named for each
  1750 constructor).  INCOMPATIBILITY.
  1751 
  1752 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1753 rules are generated for each domain, INCOMPATIBILITY.
  1754 
  1755   foo_bar.reach       ~> foo.reach  bar.reach
  1756   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1757 
  1758 * Some lemmas generated by the domain package have been renamed for
  1759 consistency with the datatype package, INCOMPATIBILITY.
  1760 
  1761   foo.ind        ~> foo.induct
  1762   foo.finite_ind ~> foo.finite_induct
  1763   foo.coind      ~> foo.coinduct
  1764   foo.casedist   ~> foo.exhaust
  1765   foo.exhaust    ~> foo.nchotomy
  1766 
  1767 * For consistency with other definition packages, the fixrec package
  1768 now generates qualified theorem names, INCOMPATIBILITY.
  1769 
  1770   foo_simps  ~> foo.simps
  1771   foo_unfold ~> foo.unfold
  1772   foo_induct ~> foo.induct
  1773 
  1774 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1775 method and internal fixrec proofs now use the default simpset instead.
  1776 INCOMPATIBILITY.
  1777 
  1778 * The "contlub" predicate has been removed.  Proof scripts should use
  1779 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1780 
  1781 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1782 
  1783 * The constants cpair, cfst, and csnd have been removed in favor of
  1784 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1785 
  1786 
  1787 *** ML ***
  1788 
  1789 * Antiquotations for basic formal entities:
  1790 
  1791     @{class NAME}         -- type class
  1792     @{class_syntax NAME}  -- syntax representation of the above
  1793 
  1794     @{type_name NAME}     -- logical type
  1795     @{type_abbrev NAME}   -- type abbreviation
  1796     @{nonterminal NAME}   -- type of concrete syntactic category
  1797     @{type_syntax NAME}   -- syntax representation of any of the above
  1798 
  1799     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1800     @{const_abbrev NAME}  -- abbreviated constant
  1801     @{const_syntax NAME}  -- syntax representation of any of the above
  1802 
  1803 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1804 syntax constant (cf. 'syntax' command).
  1805 
  1806 * Antiquotation @{make_string} inlines a function to print arbitrary
  1807 values similar to the ML toplevel.  The result is compiler dependent
  1808 and may fall back on "?" in certain situations.
  1809 
  1810 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1811 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1812 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1813 not work with the asynchronous Isar document model.
  1814 
  1815 * Configuration options now admit dynamic default values, depending on
  1816 the context or even global references.
  1817 
  1818 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1819 uses an efficient external library if available (for Poly/ML).
  1820 
  1821 * Renamed some important ML structures, while keeping the old names
  1822 for some time as aliases within the structure Legacy:
  1823 
  1824   OuterKeyword  ~>  Keyword
  1825   OuterLex      ~>  Token
  1826   OuterParse    ~>  Parse
  1827   OuterSyntax   ~>  Outer_Syntax
  1828   PrintMode     ~>  Print_Mode
  1829   SpecParse     ~>  Parse_Spec
  1830   ThyInfo       ~>  Thy_Info
  1831   ThyLoad       ~>  Thy_Load
  1832   ThyOutput     ~>  Thy_Output
  1833   TypeInfer     ~>  Type_Infer
  1834 
  1835 Note that "open Legacy" simplifies porting of sources, but forgetting
  1836 to remove it again will complicate porting again in the future.
  1837 
  1838 * Most operations that refer to a global context are named
  1839 accordingly, e.g. Simplifier.global_context or
  1840 ProofContext.init_global.  There are some situations where a global
  1841 context actually works, but under normal circumstances one needs to
  1842 pass the proper local context through the code!
  1843 
  1844 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1845 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1846 Pretty.pp argument to merge, which is absent in the standard
  1847 Theory_Data version.
  1848 
  1849 * Sorts.certify_sort and derived "cert" operations for types and terms
  1850 no longer minimize sorts.  Thus certification at the boundary of the
  1851 inference kernel becomes invariant under addition of class relations,
  1852 which is an important monotonicity principle.  Sorts are now minimized
  1853 in the syntax layer only, at the boundary between the end-user and the
  1854 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1855 explicitly in rare situations.
  1856 
  1857 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1858 emphasize that this is in no way a standard operation.
  1859 INCOMPATIBILITY.
  1860 
  1861 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1862 usual for resolution.  Rare INCOMPATIBILITY.
  1863 
  1864 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1865 to emphasize that these only work in a global situation (which is
  1866 quite rare).
  1867 
  1868 * Curried take and drop in library.ML; negative length is interpreted
  1869 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1870 
  1871 * Proof terms: type substitutions on proof constants now use canonical
  1872 order of type variables.  INCOMPATIBILITY for tools working with proof
  1873 terms.
  1874 
  1875 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1876 may no longer carry premises.  User-level specifications are
  1877 transformed accordingly by Thm.add_axiom/add_def.
  1878 
  1879 
  1880 *** System ***
  1881 
  1882 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1883 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1884 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1885 
  1886 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1887 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1888 respectively.
  1889 
  1890 * Old lib/scripts/polyml-platform is superseded by the
  1891 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1892 variant, even on a 64 bit machine.  The following example setting
  1893 prefers 64 bit if available:
  1894 
  1895   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1896 
  1897 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1898 Isabelle/Scala layer for advanced prover interaction and integration.
  1899 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1900 component.
  1901 
  1902 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1903 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1904 similar to the default assignment of the document preparation system
  1905 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1906 provides some operations for direct access to the font without asking
  1907 the user for manual installation.
  1908 
  1909 
  1910 
  1911 New in Isabelle2009-1 (December 2009)
  1912 -------------------------------------
  1913 
  1914 *** General ***
  1915 
  1916 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1917 one backslash should be used, even in ML sources.
  1918 
  1919 
  1920 *** Pure ***
  1921 
  1922 * Locale interpretation propagates mixins along the locale hierarchy.
  1923 The currently only available mixins are the equations used to map
  1924 local definitions to terms of the target domain of an interpretation.
  1925 
  1926 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1927 loc" to print all interpretations of locale "loc" in the theory.
  1928 Interpretations in proofs are not shown.
  1929 
  1930 * Thoroughly revised locales tutorial.  New section on conditional
  1931 interpretation.
  1932 
  1933 * On instantiation of classes, remaining undefined class parameters
  1934 are formally declared.  INCOMPATIBILITY.
  1935 
  1936 
  1937 *** Document preparation ***
  1938 
  1939 * New generalized style concept for printing terms: @{foo (style) ...}
  1940 instead of @{foo_style style ...}  (old form is still retained for
  1941 backward compatibility).  Styles can be also applied for
  1942 antiquotations prop, term_type and typeof.
  1943 
  1944 
  1945 *** HOL ***
  1946 
  1947 * New proof method "smt" for a combination of first-order logic with
  1948 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1949 fixed-size bitvectors; there is also basic support for higher-order
  1950 features (esp. lambda abstractions).  It is an incomplete decision
  1951 procedure based on external SMT solvers using the oracle mechanism;
  1952 for the SMT solver Z3, this method is proof-producing.  Certificates
  1953 are provided to avoid calling the external solvers solely for
  1954 re-checking proofs.  Due to a remote SMT service there is no need for
  1955 installing SMT solvers locally.  See src/HOL/SMT.
  1956 
  1957 * New commands to load and prove verification conditions generated by
  1958 the Boogie program verifier or derived systems (e.g. the Verifying C
  1959 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1960 
  1961 * New counterexample generator tool 'nitpick' based on the Kodkod
  1962 relational model finder.  See src/HOL/Tools/Nitpick and
  1963 src/HOL/Nitpick_Examples.
  1964 
  1965 * New commands 'code_pred' and 'values' to invoke the predicate
  1966 compiler and to enumerate values of inductive predicates.
  1967 
  1968 * A tabled implementation of the reflexive transitive closure.
  1969 
  1970 * New implementation of quickcheck uses generic code generator;
  1971 default generators are provided for all suitable HOL types, records
  1972 and datatypes.  Old quickcheck can be re-activated importing theory
  1973 Library/SML_Quickcheck.
  1974 
  1975 * New testing tool Mirabelle for automated proof tools.  Applies
  1976 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1977 every proof step in a theory.  To be used in batch mode via the
  1978 "mirabelle" utility.
  1979 
  1980 * New proof method "sos" (sum of squares) for nonlinear real
  1981 arithmetic (originally due to John Harison). It requires theory
  1982 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1983 works well in practice on quantifier-free real arithmetic with +, -,
  1984 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1985 inequalities between polynomials.  It makes use of external
  1986 semidefinite programming solvers.  Method "sos" generates a
  1987 certificate that can be pasted into the proof thus avoiding the need
  1988 to call an external tool every time the proof is checked.  See
  1989 src/HOL/Library/Sum_Of_Squares.
  1990 
  1991 * New method "linarith" invokes existing linear arithmetic decision
  1992 procedure only.
  1993 
  1994 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1995 
  1996 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1997 Causes full type information to be output to the ATPs.  This slows
  1998 ATPs down considerably but eliminates a source of unsound "proofs"
  1999 that fail later.
  2000 
  2001 * New method "metisFT": A version of metis that uses full type
  2002 information in order to avoid failures of proof reconstruction.
  2003 
  2004 * New evaluator "approximate" approximates an real valued term using
  2005 the same method as the approximation method.
  2006 
  2007 * Method "approximate" now supports arithmetic expressions as
  2008 boundaries of intervals and implements interval splitting and Taylor
  2009 series expansion.
  2010 
  2011 * ML antiquotation @{code_datatype} inserts definition of a datatype
  2012 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  2013 
  2014 * New theory SupInf of the supremum and infimum operators for sets of
  2015 reals.
  2016 
  2017 * New theory Probability, which contains a development of measure
  2018 theory, eventually leading to Lebesgue integration and probability.
  2019 
  2020 * Extended Multivariate Analysis to include derivation and Brouwer's
  2021 fixpoint theorem.
  2022 
  2023 * Reorganization of number theory, INCOMPATIBILITY:
  2024   - new number theory development for nat and int, in theories Divides
  2025     and GCD as well as in new session Number_Theory
  2026   - some constants and facts now suffixed with _nat and _int
  2027     accordingly
  2028   - former session NumberTheory now named Old_Number_Theory, including
  2029     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  2030   - moved theory Pocklington from src/HOL/Library to
  2031     src/HOL/Old_Number_Theory
  2032 
  2033 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  2034 lcm of finite and infinite sets. It is shown that they form a complete
  2035 lattice.
  2036 
  2037 * Class semiring_div requires superclass no_zero_divisors and proof of
  2038 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  2039 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  2040 generalized to class semiring_div, subsuming former theorems
  2041 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  2042 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  2043 INCOMPATIBILITY.
  2044 
  2045 * Refinements to lattice classes and sets:
  2046   - less default intro/elim rules in locale variant, more default
  2047     intro/elim rules in class variant: more uniformity
  2048   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  2049     le_inf_iff
  2050   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  2051     sup_aci)
  2052   - renamed ACI to inf_sup_aci
  2053   - new class "boolean_algebra"
  2054   - class "complete_lattice" moved to separate theory
  2055     "Complete_Lattice"; corresponding constants (and abbreviations)
  2056     renamed and with authentic syntax:
  2057     Set.Inf ~>    Complete_Lattice.Inf
  2058     Set.Sup ~>    Complete_Lattice.Sup
  2059     Set.INFI ~>   Complete_Lattice.INFI
  2060     Set.SUPR ~>   Complete_Lattice.SUPR
  2061     Set.Inter ~>  Complete_Lattice.Inter
  2062     Set.Union ~>  Complete_Lattice.Union
  2063     Set.INTER ~>  Complete_Lattice.INTER
  2064     Set.UNION ~>  Complete_Lattice.UNION
  2065   - authentic syntax for
  2066     Set.Pow
  2067     Set.image
  2068   - mere abbreviations:
  2069     Set.empty               (for bot)
  2070     Set.UNIV                (for top)
  2071     Set.inter               (for inf, formerly Set.Int)
  2072     Set.union               (for sup, formerly Set.Un)
  2073     Complete_Lattice.Inter  (for Inf)
  2074     Complete_Lattice.Union  (for Sup)
  2075     Complete_Lattice.INTER  (for INFI)
  2076     Complete_Lattice.UNION  (for SUPR)
  2077   - object-logic definitions as far as appropriate
  2078 
  2079 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  2080 Un_subset_iff are explicitly deleted as default simp rules; then also
  2081 their lattice counterparts le_inf_iff and le_sup_iff have to be
  2082 deleted to achieve the desired effect.
  2083 
  2084 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  2085 rules by default any longer; the same applies to min_max.inf_absorb1
  2086 etc.  INCOMPATIBILITY.
  2087 
  2088 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  2089 pred_set_conv by default.  INCOMPATIBILITY.
  2090 
  2091 * Power operations on relations and functions are now one dedicated
  2092 constant "compow" with infix syntax "^^".  Power operation on
  2093 multiplicative monoids retains syntax "^" and is now defined generic
  2094 in class power.  INCOMPATIBILITY.
  2095 
  2096 * Relation composition "R O S" now has a more standard argument order:
  2097 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2098 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2099 break, since the O_assoc rule was not rewritten like this.  Fix using
  2100 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2101 
  2102 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2103 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2104 INCOMPATIBILITY.
  2105 
  2106 * Most rules produced by inductive and datatype package have mandatory
  2107 prefixes.  INCOMPATIBILITY.
  2108 
  2109 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2110 the attribute of the same name.  Each of the theorems in the list
  2111 DERIV_intros assumes composition with an additional function and
  2112 matches a variable to the derivative, which has to be solved by the
  2113 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2114 of most elementary terms.  Former Maclauren.DERIV_tac and
  2115 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2116 INCOMPATIBILITY.
  2117 
  2118 * Code generator attributes follow the usual underscore convention:
  2119     code_unfold     replaces    code unfold
  2120     code_post       replaces    code post
  2121     etc.
  2122   INCOMPATIBILITY.
  2123 
  2124 * Renamed methods:
  2125     sizechange -> size_change
  2126     induct_scheme -> induction_schema
  2127   INCOMPATIBILITY.
  2128 
  2129 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2130 INCOMPATIBILITY, use "undefined" directly.
  2131 
  2132 * Renamed theorems:
  2133     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2134     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2135     Suc_plus1 -> Suc_eq_plus1
  2136     *anti_sym -> *antisym*
  2137     vector_less_eq_def -> vector_le_def
  2138   INCOMPATIBILITY.
  2139 
  2140 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2141 INCOMPATIBILITY.
  2142 
  2143 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2144 INCOMPATIBILITY.
  2145 
  2146 
  2147 *** HOLCF ***
  2148 
  2149 * Theory Representable defines a class "rep" of domains that are
  2150 representable (via an ep-pair) in the universal domain type "udom".
  2151 Instances are provided for all type constructors defined in HOLCF.
  2152 
  2153 * The 'new_domain' command is a purely definitional version of the
  2154 domain package, for representable domains.  Syntax is identical to the
  2155 old domain package.  The 'new_domain' package also supports indirect
  2156 recursion using previously-defined type constructors.  See
  2157 src/HOLCF/ex/New_Domain.thy for examples.
  2158 
  2159 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2160 on the left-hand side of an equation, and then performs
  2161 simplification.  Rewriting is done using rules declared with the
  2162 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2163 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2164 
  2165 * The pattern-match compiler in 'fixrec' can now handle constructors
  2166 with HOL function types.  Pattern-match combinators for the Pair
  2167 constructor are pre-configured.
  2168 
  2169 * The 'fixrec' package now produces better fixed-point induction rules
  2170 for mutually-recursive definitions:  Induction rules have conclusions
  2171 of the form "P foo bar" instead of "P <foo, bar>".
  2172 
  2173 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2174 been renamed to "below".  The name "below" now replaces "less" in many
  2175 theorem names.  (Legacy theorem names using "less" are still supported
  2176 as well.)
  2177 
  2178 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2179 patterns can be used to generate strictness rules, or to make
  2180 functions more strict (much like the bang-patterns supported by the
  2181 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2182 examples.
  2183 
  2184 
  2185 *** ML ***
  2186 
  2187 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2188 errors and run-time exceptions, including detailed source positions.
  2189 
  2190 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2191 identified entries, with some additional information such as source
  2192 position, logical grouping etc.
  2193 
  2194 * Theory and context data is now introduced by the simplified and
  2195 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2196 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2197 copy operation) is still available for some time.
  2198 
  2199 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2200 provides a high-level programming interface to synchronized state
  2201 variables with atomic update.  This works via pure function
  2202 application within a critical section -- its runtime should be as
  2203 short as possible; beware of deadlocks if critical code is nested,
  2204 either directly or indirectly via other synchronized variables!
  2205 
  2206 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2207 wraps raw ML references, explicitly indicating their non-thread-safe
  2208 behaviour.  The Isar toplevel keeps this structure open, to
  2209 accommodate Proof General as well as quick and dirty interactive
  2210 experiments with references.
  2211 
  2212 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2213 parallel tactical reasoning.
  2214 
  2215 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2216 are similar to SUBPROOF, but are slightly more flexible: only the
  2217 specified parts of the subgoal are imported into the context, and the
  2218 body tactic may introduce new subgoals and schematic variables.
  2219 
  2220 * Old tactical METAHYPS, which does not observe the proof context, has
  2221 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2222 or Subgoal.FOCUS etc.
  2223 
  2224 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2225 functors have their own ML name space there is no point to mark them
  2226 separately.)  Minor INCOMPATIBILITY.
  2227 
  2228 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2229 
  2230 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2231 INCOMPATIBILITY.
  2232 
  2233 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2234 mode, which avoids critical setmp.
  2235 
  2236 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2237 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2238 Attrib/Method.setup introduced in Isabelle2009.
  2239 
  2240 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2241 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2242 last resort.  INCOMPATIBILITY.
  2243 
  2244 * Display.pretty_thm now requires a proper context (cf. former
  2245 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2246 or even Display.pretty_thm_without_context as last resort.
  2247 INCOMPATIBILITY.
  2248 
  2249 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2250 Syntax.pretty_typ/term directly, preferably with proper context
  2251 instead of global theory.
  2252 
  2253 
  2254 *** System ***
  2255 
  2256 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2257 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2258 usedir option -q.
  2259 
  2260 * Support for additional "Isabelle components" via etc/components, see
  2261 also the system manual.
  2262 
  2263 * The isabelle makeall tool now operates on all components with
  2264 IsaMakefile, not just hardwired "logics".
  2265 
  2266 * Removed "compress" option from isabelle-process and isabelle usedir;
  2267 this is always enabled.
  2268 
  2269 * Discontinued support for Poly/ML 4.x versions.
  2270 
  2271 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2272 on a given logic image.  This requires the lighttpd webserver and is
  2273 currently supported on Linux only.
  2274 
  2275 
  2276 
  2277 New in Isabelle2009 (April 2009)
  2278 --------------------------------
  2279 
  2280 *** General ***
  2281 
  2282 * Simplified main Isabelle executables, with less surprises on
  2283 case-insensitive file-systems (such as Mac OS).
  2284 
  2285   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2286     "isatool."
  2287 
  2288   - The former "isabelle" alias for "isabelle-process" has been
  2289     removed (should rarely occur to regular users).
  2290 
  2291   - The former "isabelle-interface" and its alias "Isabelle" have been
  2292     removed (interfaces are now regular Isabelle tools).
  2293 
  2294 Within scripts and make files, the Isabelle environment variables
  2295 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2296 respectively.  (The latter are still available as legacy feature.)
  2297 
  2298 The old isabelle-interface wrapper could react in confusing ways if
  2299 the interface was uninstalled or changed otherwise.  Individual
  2300 interface tool configuration is now more explicit, see also the
  2301 Isabelle system manual.  In particular, Proof General is now available
  2302 via "isabelle emacs".
  2303 
  2304 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2305 purge installed copies of Isabelle executables and re-run "isabelle
  2306 install -p ...", or use symlinks.
  2307 
  2308 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2309 old ~/isabelle, which was slightly non-standard and apt to cause
  2310 surprises on case-insensitive file-systems (such as Mac OS).
  2311 
  2312 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2313 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2314 care is required when using older releases of Isabelle.  Note that
  2315 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2316 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2317 
  2318 * Proofs of fully specified statements are run in parallel on
  2319 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2320 a regular 4-core machine, if the initial heap space is made reasonably
  2321 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2322 
  2323 * The main reference manuals ("isar-ref", "implementation", and
  2324 "system") have been updated and extended.  Formally checked references
  2325 as hyperlinks are now available uniformly.
  2326 
  2327 
  2328 *** Pure ***
  2329 
  2330 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2331 respects.  The most important changes are listed below.  See the
  2332 Tutorial on Locales ("locales" manual) for details.
  2333 
  2334 - In locale expressions, instantiation replaces renaming.  Parameters
  2335 must be declared in a for clause.  To aid compatibility with previous
  2336 parameter inheritance, in locale declarations, parameters that are not
  2337 'touched' (instantiation position "_" or omitted) are implicitly added
  2338 with their syntax at the beginning of the for clause.
  2339 
  2340 - Syntax from abbreviations and definitions in locales is available in
  2341 locale expressions and context elements.  The latter is particularly
  2342 useful in locale declarations.
  2343 
  2344 - More flexible mechanisms to qualify names generated by locale
  2345 expressions.  Qualifiers (prefixes) may be specified in locale
  2346 expressions, and can be marked as mandatory (syntax: "name!:") or
  2347 optional (syntax "name?:").  The default depends for plain "name:"
  2348 depends on the situation where a locale expression is used: in
  2349 commands 'locale' and 'sublocale' prefixes are optional, in
  2350 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2351 implicit qualifiers derived from the parameter names of a locale are
  2352 no longer generated.
  2353 
  2354 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2355 instantiation clause in "interpretation" and "interpret" (square
  2356 brackets) is no longer available.  Use locale expressions.
  2357 
  2358 - When converting proof scripts, mandatory qualifiers in
  2359 'interpretation' and 'interpret' should be retained by default, even
  2360 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2361 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2362 in locale expressions range over a single locale instance only.
  2363 
  2364 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2365 In existing theorem specifications replace the includes element by the
  2366 respective context elements of the included locale, omitting those
  2367 that are already present in the theorem specification.  Multiple
  2368 assume elements of a locale should be replaced by a single one
  2369 involving the locale predicate.  In the proof body, declarations (most
  2370 notably theorems) may be regained by interpreting the respective
  2371 locales in the proof context as required (command "interpret").
  2372 
  2373 If using "includes" in replacement of a target solely because the
  2374 parameter types in the theorem are not as general as in the target,
  2375 consider declaring a new locale with additional type constraints on
  2376 the parameters (context element "constrains").
  2377 
  2378 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2379 
  2380 - Locale interpretation commands no longer attempt to simplify goal.
  2381 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2382 methods intro_locales and unfold_locales to clarify.
  2383 
  2384 - Locale interpretation commands no longer accept interpretation
  2385 attributes.  INCOMPATIBILITY.
  2386 
  2387 * Class declaration: so-called "base sort" must not be given in import
  2388 list any longer, but is inferred from the specification.  Particularly
  2389 in HOL, write
  2390 
  2391     class foo = ...
  2392 
  2393 instead of
  2394 
  2395     class foo = type + ...
  2396 
  2397 * Class target: global versions of theorems stemming do not carry a
  2398 parameter prefix any longer.  INCOMPATIBILITY.
  2399 
  2400 * Class 'instance' command no longer accepts attached definitions.
  2401 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2402 
  2403 * Recovered hiding of consts, which was accidentally broken in
  2404 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2405 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2406 
  2407 * Slightly more coherent Pure syntax, with updated documentation in
  2408 isar-ref manual.  Removed locales meta_term_syntax and
  2409 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2410 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2411 directly in regular applications.
  2412 
  2413 * There is a new syntactic category "float_const" for signed decimal
  2414 fractions (e.g. 123.45 or -123.45).
  2415 
  2416 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2417 interface with 'setup' command instead.
  2418 
  2419 * Command 'local_setup' is similar to 'setup', but operates on a local
  2420 theory context.
  2421 
  2422 * The 'axiomatization' command now only works within a global theory
  2423 context.  INCOMPATIBILITY.
  2424 
  2425 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2426 hypotheses.  Sorts required in the course of reasoning need to be
  2427 covered by the constraints in the initial statement, completed by the
  2428 type instance information of the background theory.  Non-trivial sort
  2429 hypotheses, which rarely occur in practice, may be specified via
  2430 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2431 
  2432   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2433 
  2434 The result contains an implicit sort hypotheses as before --
  2435 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2436 normalization.
  2437 
  2438 * Generalized Isar history, with support for linear undo, direct state
  2439 addressing etc.
  2440 
  2441 * Changed defaults for unify configuration options:
  2442 
  2443   unify_trace_bound = 50 (formerly 25)
  2444   unify_search_bound = 60 (formerly 30)
  2445 
  2446 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2447 
  2448   a) On theory merge, the last set of code equations for a particular
  2449      constant is taken (in accordance with the policy applied by other
  2450      parts of the code generator framework).
  2451 
  2452   b) Code equations stemming from explicit declarations (e.g. code
  2453      attribute) gain priority over default code equations stemming
  2454      from definition, primrec, fun etc.
  2455 
  2456 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2457 
  2458 * Unified theorem tables for both code generators.  Thus [code
  2459 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2460 
  2461 * Command 'find_consts' searches for constants based on type and name
  2462 patterns, e.g.
  2463 
  2464     find_consts "_ => bool"
  2465 
  2466 By default, matching is against subtypes, but it may be restricted to
  2467 the whole type.  Searching by name is possible.  Multiple queries are
  2468 conjunctive and queries may be negated by prefixing them with a
  2469 hyphen:
  2470 
  2471     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2472 
  2473 * New 'find_theorems' criterion "solves" matches theorems that
  2474 directly solve the current goal (modulo higher-order unification).
  2475 
  2476 * Auto solve feature for main theorem statements: whenever a new goal
  2477 is stated, "find_theorems solves" is called; any theorems that could
  2478 solve the lemma directly are listed as part of the goal state.
  2479 Cf. associated options in Proof General Isabelle settings menu,
  2480 enabled by default, with reasonable timeout for pathological cases of
  2481 higher-order unification.
  2482 
  2483 
  2484 *** Document preparation ***
  2485 
  2486 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2487 demanding keyword 'by' and supporting the full method expression
  2488 syntax just like the Isar command 'by'.
  2489 
  2490 
  2491 *** HOL ***
  2492 
  2493 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2494 points Main and Complex_Main remain as before.
  2495 
  2496 * Logic image HOL-Plain provides a minimal HOL with the most important
  2497 tools available (inductive, datatype, primrec, ...).  This facilitates
  2498 experimentation and tool development.  Note that user applications
  2499 (and library theories) should never refer to anything below theory
  2500 Main, as before.
  2501 
  2502 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2503 experimentation due to shorter build times.
  2504 
  2505 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2506 were previously part of former HOL-Complex.  Entry point Hyperreal
  2507 remains valid, but theories formerly using Complex_Main should now use
  2508 new entry point Hypercomplex.
  2509 
  2510 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2511 Posix processes.  Avoids potentially expensive forking of the ML
  2512 process.  New thread-based implementation also works on non-Unix
  2513 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2514 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2515 commands are covered in the isar-ref manual.
  2516 
  2517 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2518 sledgehammer without local ATP installation (Vampire etc.). Other
  2519 provers may be included via suitable ML wrappers, see also
  2520 src/HOL/ATP_Linkup.thy.
  2521 
  2522 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2523 menu.
  2524 
  2525 * The metis method no longer fails because the theorem is too trivial
  2526 (contains the empty clause).
  2527 
  2528 * The metis method now fails in the usual manner, rather than raising
  2529 an exception, if it determines that it cannot prove the theorem.
  2530 
  2531 * Method "coherent" implements a prover for coherent logic (see also
  2532 src/Tools/coherent.ML).
  2533 
  2534 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2535 "undefined" is the right choice to replace "arbitrary", though
  2536 logically there is no difference.  INCOMPATIBILITY.
  2537 
  2538 * Command "value" now integrates different evaluation mechanisms.  The
  2539 result of the first successful evaluation mechanism is printed.  In
  2540 square brackets a particular named evaluation mechanisms may be
  2541 specified (currently, [SML], [code] or [nbe]).  See further
  2542 src/HOL/ex/Eval_Examples.thy.
  2543 
  2544 * Normalization by evaluation now allows non-leftlinear equations.
  2545 Declare with attribute [code nbe].
  2546 
  2547 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2548 as the structured Isar versions "cases" and "induct", cf. the
  2549 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2550 are now presented as a list of individual projections
  2551 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2552 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2553 rare situations a different rule is selected --- notably nested tuple
  2554 elimination instead of former prod.exhaust: use explicit (case_tac t
  2555 rule: prod.exhaust) here.
  2556 
  2557 * Attributes "cases", "induct", "coinduct" support "del" option.
  2558 
  2559 * Removed fact "case_split_thm", which duplicates "case_split".
  2560 
  2561 * The option datatype has been moved to a new theory Option.  Renamed
  2562 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2563 
  2564 * New predicate "strict_mono" classifies strict functions on partial
  2565 orders.  With strict functions on linear orders, reasoning about
  2566 (in)equalities is facilitated by theorems "strict_mono_eq",
  2567 "strict_mono_less_eq" and "strict_mono_less".
  2568 
  2569 * Some set operations are now proper qualified constants with
  2570 authentic syntax.  INCOMPATIBILITY:
  2571 
  2572     op Int ~>   Set.Int
  2573     op Un ~>    Set.Un
  2574     INTER ~>    Set.INTER
  2575     UNION ~>    Set.UNION
  2576     Inter ~>    Set.Inter
  2577     Union ~>    Set.Union
  2578     {} ~>       Set.empty
  2579     UNIV ~>     Set.UNIV
  2580 
  2581 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2582 theory Set.
  2583 
  2584 * Auxiliary class "itself" has disappeared -- classes without any
  2585 parameter are treated as expected by the 'class' command.
  2586 
  2587 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2588 
  2589 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2590 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2591 
  2592 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2593 method "approximation".  It proves formulas on real values by using
  2594 interval arithmetic.  In the formulas are also the transcendental
  2595 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2596 allowed. For examples see
  2597 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2598 
  2599 * Theory "Reflection" now resides in HOL/Library.
  2600 
  2601 * Entry point to Word library now simply named "Word".
  2602 INCOMPATIBILITY.
  2603 
  2604 * Made source layout more coherent with logical distribution
  2605 structure:
  2606 
  2607     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2608     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2609     src/HOL/Library/GCD.thy ~> src/HOL/
  2610     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2611     src/HOL/Library/Parity.thy ~> src/HOL/
  2612     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2613     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2614     src/HOL/Real/Lubs.thy ~> src/HOL/
  2615     src/HOL/Real/PReal.thy ~> src/HOL/
  2616     src/HOL/Real/Rational.thy ~> src/HOL/
  2617     src/HOL/Real/RComplete.thy ~> src/HOL/
  2618     src/HOL/Real/RealDef.thy ~> src/HOL/
  2619     src/HOL/Real/RealPow.thy ~> src/HOL/
  2620     src/HOL/Real/Real.thy ~> src/HOL/
  2621     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2622     src/HOL/Complex/Complex.thy ~> src/HOL/
  2623     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2624     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2625     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2626     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2627     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2628     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2629     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2630     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2631     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2632     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2633     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2634     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2635     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2636     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2637     src/HOL/Real/Float ~> src/HOL/Library/
  2638     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2639     src/HOL/Real/RealVector.thy ~> src/HOL/
  2640 
  2641     src/HOL/arith_data.ML ~> src/HOL/Tools
  2642     src/HOL/hologic.ML ~> src/HOL/Tools
  2643     src/HOL/simpdata.ML ~> src/HOL/Tools
  2644     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2645     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2646     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2647     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2648     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2649     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2650     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2651 
  2652     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2653     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2654     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2655     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2656     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2657     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2658 
  2659 * If methods "eval" and "evaluation" encounter a structured proof
  2660 state with !!/==>, only the conclusion is evaluated to True (if
  2661 possible), avoiding strange error messages.
  2662 
  2663 * Method "sizechange" automates termination proofs using (a
  2664 modification of) the size-change principle.  Requires SAT solver.  See
  2665 src/HOL/ex/Termination.thy for examples.
  2666 
  2667 * Simplifier: simproc for let expressions now unfolds if bound
  2668 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2669 
  2670 * Method "arith": Linear arithmetic now ignores all inequalities when
  2671 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2672 
  2673 * New attribute "arith" for facts that should always be used
  2674 automatically by arithmetic. It is intended to be used locally in
  2675 proofs, e.g.
  2676 
  2677   assumes [arith]: "x > 0"
  2678 
  2679 Global usage is discouraged because of possible performance impact.
  2680 
  2681 * New classes "top" and "bot" with corresponding operations "top" and
  2682 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2683 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2684 
  2685 * Changed definition lemma "less_fun_def" in order to provide an
  2686 instance for preorders on functions; use lemma "less_le" instead.
  2687 INCOMPATIBILITY.
  2688 
  2689 * Theory Orderings: class "wellorder" moved here, with explicit
  2690 induction rule "less_induct" as assumption.  For instantiation of
  2691 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2692 INCOMPATIBILITY.
  2693 
  2694 * Theory Orderings: added class "preorder" as superclass of "order".
  2695 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2696 etc. slightly changed.  Some theorems named order_class.* now named
  2697 preorder_class.*.
  2698 
  2699 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2700 "diag" to "Id_on".
  2701 
  2702 * Theory Finite_Set: added a new fold combinator of type
  2703 
  2704   ('a => 'b => 'b) => 'b => 'a set => 'b
  2705 
  2706 Occasionally this is more convenient than the old fold combinator
  2707 which is now defined in terms of the new one and renamed to
  2708 fold_image.
  2709 
  2710 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2711 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2712 extended with further lemmas!).  At the moment both still exist but
  2713 the former will disappear at some point.
  2714 
  2715 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2716 class recpower.  Type-specific simp rules for various recpower types
  2717 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2718 
  2719 rat_power_0    -> power_0
  2720 rat_power_Suc  -> power_Suc
  2721 realpow_0      -> power_0
  2722 realpow_Suc    -> power_Suc
  2723 complexpow_0   -> power_0
  2724 complexpow_Suc -> power_Suc
  2725 power_poly_0   -> power_0
  2726 power_poly_Suc -> power_Suc
  2727 
  2728 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2729 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2730 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2731 of lemmas from Divides has been generalized from nat to class
  2732 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2733 renames resulting from duplicate elimination:
  2734 
  2735     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2736     zero_dvd_iff ~>         dvd_0_left_iff
  2737     dvd_0 ~>                dvd_0_right
  2738     DIVISION_BY_ZERO_DIV ~> div_by_0
  2739     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2740     mult_div ~>             div_mult_self2_is_id
  2741     mult_mod ~>             mod_mult_self2_is_0
  2742 
  2743 * Theory IntDiv: removed many lemmas that are instances of class-based
  2744 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2745 rename old lemmas as follows:
  2746 
  2747 dvd_diff               -> nat_dvd_diff
  2748 dvd_zminus_iff         -> dvd_minus_iff
  2749 mod_add1_eq            -> mod_add_eq
  2750 mod_mult1_eq           -> mod_mult_right_eq
  2751 mod_mult1_eq'          -> mod_mult_left_eq
  2752 mod_mult_distrib_mod   -> mod_mult_eq
  2753 nat_mod_add_left_eq    -> mod_add_left_eq
  2754 nat_mod_add_right_eq   -> mod_add_right_eq
  2755 nat_mod_div_trivial    -> mod_div_trivial
  2756 nat_mod_mod_trivial    -> mod_mod_trivial
  2757 zdiv_zadd_self1        -> div_add_self1
  2758 zdiv_zadd_self2        -> div_add_self2
  2759 zdiv_zmult_self1       -> div_mult_self2_is_id
  2760 zdiv_zmult_self2       -> div_mult_self1_is_id
  2761 zdvd_triv_left         -> dvd_triv_left
  2762 zdvd_triv_right        -> dvd_triv_right
  2763 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2764 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2765 zmod_zadd_left_eq      -> mod_add_left_eq
  2766 zmod_zadd_right_eq     -> mod_add_right_eq
  2767 zmod_zadd_self1        -> mod_add_self1
  2768 zmod_zadd_self2        -> mod_add_self2
  2769 zmod_zadd1_eq          -> mod_add_eq
  2770 zmod_zdiff1_eq         -> mod_diff_eq
  2771 zmod_zdvd_zmod         -> mod_mod_cancel
  2772 zmod_zmod_cancel       -> mod_mod_cancel
  2773 zmod_zmult_self1       -> mod_mult_self2_is_0
  2774 zmod_zmult_self2       -> mod_mult_self1_is_0
  2775 zmod_1                 -> mod_by_1
  2776 zdiv_1                 -> div_by_1
  2777 zdvd_abs1              -> abs_dvd_iff
  2778 zdvd_abs2              -> dvd_abs_iff
  2779 zdvd_refl              -> dvd_refl
  2780 zdvd_trans             -> dvd_trans
  2781 zdvd_zadd              -> dvd_add
  2782 zdvd_zdiff             -> dvd_diff
  2783 zdvd_zminus_iff        -> dvd_minus_iff
  2784 zdvd_zminus2_iff       -> minus_dvd_iff
  2785 zdvd_zmultD            -> dvd_mult_right
  2786 zdvd_zmultD2           -> dvd_mult_left
  2787 zdvd_zmult_mono        -> mult_dvd_mono
  2788 zdvd_0_right           -> dvd_0_right
  2789 zdvd_0_left            -> dvd_0_left_iff
  2790 zdvd_1_left            -> one_dvd
  2791 zminus_dvd_iff         -> minus_dvd_iff
  2792 
  2793 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2794 
  2795 * The real numbers offer decimal input syntax: 12.34 is translated
  2796 into 1234/10^2. This translation is not reversed upon output.
  2797 
  2798 * Theory Library/Polynomial defines an abstract type 'a poly of
  2799 univariate polynomials with coefficients of type 'a.  In addition to
  2800 the standard ring operations, it also supports div and mod.  Code
  2801 generation is also supported, using list-style constructors.
  2802 
  2803 * Theory Library/Inner_Product defines a class of real_inner for real
  2804 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2805 => real.  Class real_inner is a subclass of real_normed_vector from
  2806 theory RealVector.
  2807 
  2808 * Theory Library/Product_Vector provides instances for the product
  2809 type 'a * 'b of several classes from RealVector and Inner_Product.
  2810 Definitions of addition, subtraction, scalar multiplication, norms,
  2811 and inner products are included.
  2812 
  2813 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2814 addition to the field operations, numerals and case syntax are also
  2815 supported.
  2816 
  2817 * Theory Library/Diagonalize provides constructive version of Cantor's
  2818 first diagonalization argument.
  2819 
  2820 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2821 zlcm (for int); carried together from various gcd/lcm developements in
  2822 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2823 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2824 may recover tupled syntax as follows:
  2825 
  2826     hide (open) const gcd
  2827     abbreviation gcd where
  2828       "gcd == (%(a, b). GCD.gcd a b)"
  2829     notation (output)
  2830       GCD.gcd ("gcd '(_, _')")
  2831 
  2832 The same works for lcm, zgcd, zlcm.
  2833 
  2834 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2835 instantiations for algebraic structures.  Removed some duplicate
  2836 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2837 
  2838 * ML antiquotation @{code} takes a constant as argument and generates
  2839 corresponding code in background and inserts name of the corresponding
  2840 resulting ML value/function/datatype constructor binding in place.
  2841 All occurrences of @{code} with a single ML block are generated
  2842 simultaneously.  Provides a generic and safe interface for
  2843 instrumentalizing code generation.  See
  2844 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2845 In future you ought to refrain from ad-hoc compiling generated SML
  2846 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2847 cannot refer to constants for which user-defined serializations are
  2848 set.  Refer to the corresponding ML counterpart directly in that
  2849 cases.
  2850 
  2851 * Command 'rep_datatype': instead of theorem names the command now
  2852 takes a list of terms denoting the constructors of the type to be
  2853 represented as datatype.  The characteristic theorems have to be
  2854 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2855 have disappeared in favour of existing ones:
  2856 
  2857     unit_induct                 ~> unit.induct
  2858     prod_induct                 ~> prod.induct
  2859     sum_induct                  ~> sum.induct
  2860     Suc_Suc_eq                  ~> nat.inject
  2861     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2862 
  2863 
  2864 *** HOL-Algebra ***
  2865 
  2866 * New locales for orders and lattices where the equivalence relation
  2867 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2868 locales use a record structure with field eq for the equivalence.
  2869 
  2870 * New theory of factorial domains.
  2871 
  2872 * Units_l_inv and Units_r_inv are now simp rules by default.
  2873 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2874 and/or r_inv will now also require deletion of these lemmas.
  2875 
  2876 * Renamed the following theorems, INCOMPATIBILITY:
  2877 
  2878 UpperD ~> Upper_memD
  2879 LowerD ~> Lower_memD
  2880 least_carrier ~> least_closed
  2881 greatest_carrier ~> greatest_closed
  2882 greatest_Lower_above ~> greatest_Lower_below
  2883 one_zero ~> carrier_one_zero
  2884 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2885 
  2886 
  2887 *** HOL-Nominal ***
  2888 
  2889 * Nominal datatypes can now contain type-variables.
  2890 
  2891 * Commands 'nominal_inductive' and 'equivariance' work with local
  2892 theory targets.
  2893 
  2894 * Nominal primrec can now works with local theory targets and its
  2895 specification syntax now conforms to the general format as seen in
  2896 'inductive' etc.
  2897 
  2898 * Method "perm_simp" honours the standard simplifier attributes
  2899 (no_asm), (no_asm_use) etc.
  2900 
  2901 * The new predicate #* is defined like freshness, except that on the
  2902 left hand side can be a set or list of atoms.
  2903 
  2904 * Experimental command 'nominal_inductive2' derives strong induction
  2905 principles for inductive definitions.  In contrast to
  2906 'nominal_inductive', which can only deal with a fixed number of
  2907 binders, it can deal with arbitrary expressions standing for sets of
  2908 atoms to be avoided.  The only inductive definition we have at the
  2909 moment that needs this generalisation is the typing rule for Lets in
  2910 the algorithm W:
  2911 
  2912  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2913  -----------------------------------------------------------------
  2914          Gamma |- Let x be t1 in t2 : T2
  2915 
  2916 In this rule one wants to avoid all the binders that are introduced by
  2917 "close Gamma T1".  We are looking for other examples where this
  2918 feature might be useful.  Please let us know.
  2919 
  2920 
  2921 *** HOLCF ***
  2922 
  2923 * Reimplemented the simplification procedure for proving continuity
  2924 subgoals.  The new simproc is extensible; users can declare additional
  2925 continuity introduction rules with the attribute [cont2cont].
  2926 
  2927 * The continuity simproc now uses a different introduction rule for
  2928 solving continuity subgoals on terms with lambda abstractions.  In
  2929 some rare cases the new simproc may fail to solve subgoals that the
  2930 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2931 Potential INCOMPATIBILITY.
  2932 
  2933 * Command 'fixrec': specification syntax now conforms to the general
  2934 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2935 examples.  INCOMPATIBILITY.
  2936 
  2937 
  2938 *** ZF ***
  2939 
  2940 * Proof of Zorn's Lemma for partial orders.
  2941 
  2942 
  2943 *** ML ***
  2944 
  2945 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2946 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2947 depends on multithreading, so timouts will not work before Poly/ML
  2948 5.2.1!
  2949 
  2950 * High-level support for concurrent ML programming, see
  2951 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2952 particularly convenient to organize independent functional
  2953 computations.  The concept of "synchronized variables" provides a
  2954 higher-order interface for components with shared state, avoiding the
  2955 delicate details of mutexes and condition variables.  (Requires
  2956 Poly/ML 5.2.1 or later.)
  2957 
  2958 * ML bindings produced via Isar commands are stored within the Isar
  2959 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2960 become thread-safe and work with undo as expected (concerning
  2961 top-level bindings, not side-effects on global references).
  2962 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2963 compiler at runtime; really global bindings need to be given outside a
  2964 theory.  (Requires Poly/ML 5.2 or later.)
  2965 
  2966 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2967 context.  Top-level ML bindings are stored within the proof context in
  2968 a purely sequential fashion, disregarding the nested proof structure.
  2969 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2970 proof.  (Requires Poly/ML 5.2 or later.)
  2971 
  2972 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2973 and Method.setup, as well as Isar commands 'attribute_setup' and
  2974 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2975 existing code accordingly, or use plain 'setup' together with old
  2976 Method.add_method.
  2977 
  2978 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2979 to 'a -> thm, while results are always tagged with an authentic oracle
  2980 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2981 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2982 accordingly.  Note that extra performance may be gained by producing
  2983 the cterm carefully, avoiding slow Thm.cterm_of.
  2984 
  2985 * Simplified interface for defining document antiquotations via
  2986 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2987 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2988 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2989 examples.
  2990 
  2991 * More systematic treatment of long names, abstract name bindings, and
  2992 name space operations.  Basic operations on qualified names have been
  2993 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2994 Long_Name.append.  Old type bstring has been mostly replaced by
  2995 abstract type binding (see structure Binding), which supports precise
  2996 qualification by packages and local theory targets, as well as proper
  2997 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2998 bstring values into Binding.name, or better pass through abstract
  2999 bindings everywhere.  See further src/Pure/General/long_name.ML,
  3000 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  3001 
  3002 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  3003 LocalTheory.note etc.) now refer to the *full* internal name, not the
  3004 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  3005 
  3006 * Disposed old type and term read functions (Sign.read_def_typ,
  3007 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  3008 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  3009 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  3010 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  3011 resort for legacy applications.
  3012 
  3013 * Disposed old declarations, tactics, tactic combinators that refer to
  3014 the simpset or claset of an implicit theory (such as Addsimps,
  3015 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  3016 embedded ML text, or local_simpset_of with a proper context passed as
  3017 explicit runtime argument.
  3018 
  3019 * Rules and tactics that read instantiations (read_instantiate,
  3020 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  3021 context, which is required for parsing and type-checking.  Moreover,
  3022 the variables are specified as plain indexnames, not string encodings
  3023 thereof.  INCOMPATIBILITY.
  3024 
  3025 * Generic Toplevel.add_hook interface allows to analyze the result of
  3026 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  3027 for theorem dependency output of transactions resulting in a new
  3028 theory state.
  3029 
  3030 * ML antiquotations: block-structured compilation context indicated by
  3031 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  3032 
  3033   @{binding name}                         - basic name binding
  3034   @{let ?pat = term}                      - term abbreviation (HO matching)
  3035   @{note name = fact}                     - fact abbreviation
  3036   @{thm fact}                             - singleton fact (with attributes)
  3037   @{thms fact}                            - general fact (with attributes)
  3038   @{lemma prop by method}                 - singleton goal
  3039   @{lemma prop by meth1 meth2}            - singleton goal
  3040   @{lemma prop1 ... propN by method}      - general goal
  3041   @{lemma prop1 ... propN by meth1 meth2} - general goal
  3042   @{lemma (open) ...}                     - open derivation
  3043 
  3044 
  3045 *** System ***
  3046 
  3047 * The Isabelle "emacs" tool provides a specific interface to invoke
  3048 Proof General / Emacs, with more explicit failure if that is not
  3049 installed (the old isabelle-interface script silently falls back on
  3050 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  3051 installation location of the Proof General distribution.
  3052 
  3053 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  3054 the Isabelle process into a JVM/Scala application.  See
  3055 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  3056 process wrapper has been discontinued.)
  3057 
  3058 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  3059 
  3060 * Various status messages (with exact source position information) are
  3061 emitted, if proper markup print mode is enabled.  This allows
  3062 user-interface components to provide detailed feedback on internal
  3063 prover operations.
  3064 
  3065 
  3066 
  3067 New in Isabelle2008 (June 2008)
  3068 -------------------------------
  3069 
  3070 *** General ***
  3071 
  3072 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  3073 and updated, with formally checked references as hyperlinks.
  3074 
  3075 * Theory loader: use_thy (and similar operations) no longer set the
  3076 implicit ML context, which was occasionally hard to predict and in
  3077 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  3078 provides a proper context already.
  3079 
  3080 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3081 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  3082 'use' within a theory file will do the job.
  3083 
  3084 * Name space merge now observes canonical order, i.e. the second space
  3085 is inserted into the first one, while existing entries in the first
  3086 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  3087 swap theory imports.
  3088 
  3089 * Syntax: symbol \<chi> is now considered a letter.  Potential
  3090 INCOMPATIBILITY in identifier syntax etc.
  3091 
  3092 * Outer syntax: string tokens no longer admit escaped white space,
  3093 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3094 white space without escapes.
  3095 
  3096 * Outer syntax: string tokens may contain arbitrary character codes
  3097 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3098 "foo_bar".
  3099 
  3100 
  3101 *** Pure ***
  3102 
  3103 * Context-dependent token translations.  Default setup reverts locally
  3104 fixed variables, and adds hilite markup for undeclared frees.
  3105 
  3106 * Unused theorems can be found using the new command 'unused_thms'.
  3107 There are three ways of invoking it:
  3108 
  3109 (1) unused_thms
  3110      Only finds unused theorems in the current theory.
  3111 
  3112 (2) unused_thms thy_1 ... thy_n -
  3113      Finds unused theorems in the current theory and all of its ancestors,
  3114      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3115 
  3116 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3117      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3118      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3119      their ancestors.
  3120 
  3121 In order to increase the readability of the list produced by
  3122 unused_thms, theorems that have been created by a particular instance
  3123 of a theory command such as 'inductive' or 'function' are considered
  3124 to belong to the same "group", meaning that if at least one theorem in
  3125 this group is used, the other theorems in the same group are no longer
  3126 reported as unused.  Moreover, if all theorems in the group are
  3127 unused, only one theorem in the group is displayed.
  3128 
  3129 Note that proof objects have to be switched on in order for
  3130 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3131 usually the case when using Proof General with the default settings).
  3132 
  3133 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3134 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3135 duplicate fact bindings, or even accidental fact duplications.  Note
  3136 that tools may maintain dynamically scoped facts systematically, using
  3137 PureThy.add_thms_dynamic.
  3138 
  3139 * Command 'hide' now allows to hide from "fact" name space as well.
  3140 
  3141 * Eliminated destructive theorem database, simpset, claset, and
  3142 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3143 update of theories within ML code.
  3144 
  3145 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3146 INCOMPATIBILITY, object-logics depending on former Pure require
  3147 additional setup PureThy.old_appl_syntax_setup; object-logics
  3148 depending on former CPure need to refer to Pure.
  3149 
  3150 * Commands 'use' and 'ML' are now purely functional, operating on
  3151 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3152 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3153 INCOMPATIBILITY.
  3154 
  3155 * Command 'setup': discontinued implicit version with ML reference.
  3156 
  3157 * Instantiation target allows for simultaneous specification of class
  3158 instance operations together with an instantiation proof.
  3159 Type-checking phase allows to refer to class operations uniformly.
  3160 See src/HOL/Complex/Complex.thy for an Isar example and
  3161 src/HOL/Library/Eval.thy for an ML example.
  3162 
  3163 * Indexing of literal facts: be more serious about including only
  3164 facts from the visible specification/proof context, but not the
  3165 background context (locale etc.).  Affects `prop` notation and method
  3166 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3167 situations.
  3168 
  3169 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3170 "(open)" option, which used to expose internal bound variables to the
  3171 proof text.
  3172 
  3173 * Isar statements: removed obsolete case "rule_context".
  3174 INCOMPATIBILITY, better use explicit fixes/assumes.
  3175 
  3176 * Locale proofs: default proof step now includes 'unfold_locales';
  3177 hence 'proof' without argument may be used to unfold locale
  3178 predicates.
  3179 
  3180 
  3181 *** Document preparation ***
  3182 
  3183 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3184 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3185 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3186 spot); renamed link color from "darkblue" to "linkcolor" (default
  3187 value unchanged, can be redefined via \definecolor); no longer sets
  3188 "a4paper" option (unnecessary or even intrusive).
  3189 
  3190 * Antiquotation @{lemma A method} proves proposition A by the given
  3191 method (either a method name or a method name plus (optional) method
  3192 arguments in parentheses) and prints A just like @{prop A}.
  3193 
  3194 
  3195 *** HOL ***
  3196 
  3197 * New primrec package.  Specification syntax conforms in style to
  3198 definition/function/....  No separate induction rule is provided.  The
  3199 "primrec" command distinguishes old-style and new-style specifications
  3200 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3201 When adjusting theories, beware: constants stemming from new-style
  3202 primrec specifications have authentic syntax.
  3203 
  3204 * Metis prover is now an order of magnitude faster, and also works
  3205 with multithreading.
  3206 
  3207 * Metis: the maximum number of clauses that can be produced from a
  3208 theorem is now given by the attribute max_clauses.  Theorems that
  3209 exceed this number are ignored, with a warning printed.
  3210 
  3211 * Sledgehammer no longer produces structured proofs by default. To
  3212 enable, declare [[sledgehammer_full = true]].  Attributes
  3213 reconstruction_modulus, reconstruction_sorts renamed
  3214 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3215 
  3216 * Method "induct_scheme" derives user-specified induction rules
  3217 from well-founded induction and completeness of patterns. This factors
  3218 out some operations that are done internally by the function package
  3219 and makes them available separately.  See
  3220 src/HOL/ex/Induction_Scheme.thy for examples.
  3221 
  3222 * More flexible generation of measure functions for termination
  3223 proofs: Measure functions can be declared by proving a rule of the
  3224 form "is_measure f" and giving it the [measure_function] attribute.
  3225 The "is_measure" predicate is logically meaningless (always true), and
  3226 just guides the heuristic.  To find suitable measure functions, the
  3227 termination prover sets up the goal "is_measure ?f" of the appropriate
  3228 type and generates all solutions by prolog-style backwards proof using
  3229 the declared rules.
  3230 
  3231 This setup also deals with rules like 
  3232 
  3233   "is_measure f ==> is_measure (list_size f)"
  3234 
  3235 which accommodates nested datatypes that recurse through lists.
  3236 Similar rules are predeclared for products and option types.
  3237 
  3238 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3239 
  3240   INCOMPATIBILITIES:
  3241 
  3242   - Definitions of overloaded constants on sets have to be replaced by
  3243     definitions on => and bool.
  3244 
  3245   - Some definitions of overloaded operators on sets can now be proved
  3246     using the definitions of the operators on => and bool.  Therefore,
  3247     the following theorems have been renamed:
  3248 
  3249       subset_def   -> subset_eq
  3250       psubset_def  -> psubset_eq
  3251       set_diff_def -> set_diff_eq
  3252       Compl_def    -> Compl_eq
  3253       Sup_set_def  -> Sup_set_eq
  3254       Inf_set_def  -> Inf_set_eq
  3255       sup_set_def  -> sup_set_eq
  3256       inf_set_def  -> inf_set_eq
  3257 
  3258   - Due to the incompleteness of the HO unification algorithm, some
  3259     rules such as subst may require manual instantiation, if some of
  3260     the unknowns in the rule is a set.
  3261 
  3262   - Higher order unification and forward proofs:
  3263     The proof pattern
  3264 
  3265       have "P (S::'a set)" <...>
  3266       then have "EX S. P S" ..
  3267 
  3268     no longer works (due to the incompleteness of the HO unification
  3269     algorithm) and must be replaced by the pattern
  3270 
  3271       have "EX S. P S"
  3272       proof
  3273         show "P S" <...>
  3274       qed
  3275 
  3276   - Calculational reasoning with subst (or similar rules):
  3277     The proof pattern
  3278 
  3279       have "P (S::'a set)" <...>
  3280       also have "S = T" <...>
  3281       finally have "P T" .
  3282 
  3283     no longer works (for similar reasons as the previous example) and
  3284     must be replaced by something like
  3285 
  3286       have "P (S::'a set)" <...>
  3287       moreover have "S = T" <...>
  3288       ultimately have "P T" by simp
  3289 
  3290   - Tactics or packages written in ML code:
  3291     Code performing pattern matching on types via
  3292 
  3293       Type ("set", [T]) => ...
  3294 
  3295     must be rewritten. Moreover, functions like strip_type or
  3296     binder_types no longer return the right value when applied to a
  3297     type of the form
  3298 
  3299       T1 => ... => Tn => U => bool
  3300 
  3301     rather than
  3302 
  3303       T1 => ... => Tn => U set
  3304 
  3305 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3306 Wellfounded_Relations to theory Wellfounded.
  3307 
  3308 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3309 
  3310 * Class finite no longer treats UNIV as class parameter.  Use class
  3311 enum from theory Library/Enum instead to achieve a similar effect.
  3312 INCOMPATIBILITY.
  3313 
  3314 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3315 and "Cons".  INCOMPATIBILITY.
  3316 
  3317 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3318 Potential INCOMPATIBILITY.
  3319 
  3320 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3321 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3322 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3323 
  3324 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3325 the same name in theory Orderings:
  3326 
  3327   less_trans
  3328   less_linear
  3329   le_imp_less_or_eq
  3330   le_less_trans
  3331   less_le_trans
  3332   less_not_sym
  3333   less_asym
  3334 
  3335 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3336 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3337 and different variable names.
  3338 
  3339 * Library/Option_ord.thy: Canonical order on option type.
  3340 
  3341 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3342 finite maps.
  3343 
  3344 * Library/Countable.thy: Type class for countable types.
  3345 
  3346 * Theory Int: The representation of numerals has changed.  The infix
  3347 operator BIT and the bit datatype with constructors B0 and B1 have
  3348 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3349 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3350 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3351 accordingly.
  3352 
  3353 * Theory Nat: definition of <= and < on natural numbers no longer
  3354 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3355 le_def and less_def have disappeared.  Consider lemmas not_less
  3356 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3357 
  3358 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3359 (whose purpose mainly is for various fold_set functionals) have been
  3360 abandoned in favor of the existing algebraic classes
  3361 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3362 lower_semilattice (resp. upper_semilattice) and linorder.
  3363 INCOMPATIBILITY.
  3364 
  3365 * Theory Transitive_Closure: induct and cases rules now declare proper
  3366 case_names ("base" and "step").  INCOMPATIBILITY.
  3367 
  3368 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3369 lattices.  The form set-specific version is available as
  3370 Inductive.lfp_ordinal_induct_set.
  3371 
  3372 * Renamed theorems "power.simps" to "power_int.simps".
  3373 INCOMPATIBILITY.
  3374 
  3375 * Class semiring_div provides basic abstract properties of semirings
  3376 with division and modulo operations.  Subsumes former class dvd_mod.
  3377 
  3378 * Merged theories IntDef, Numeral and IntArith into unified theory
  3379 Int.  INCOMPATIBILITY.
  3380 
  3381 * Theory Library/Code_Index: type "index" now represents natural
  3382 numbers rather than integers.  INCOMPATIBILITY.
  3383 
  3384 * New class "uminus" with operation "uminus" (split of from class
  3385 "minus" which now only has operation "minus", binary).
  3386 INCOMPATIBILITY.
  3387 
  3388 * Constants "card", "internal_split", "option_map" now with authentic
  3389 syntax.  INCOMPATIBILITY.
  3390 
  3391 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3392 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3393 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3394 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3395 Sup_set_def, le_def, less_def, option_map_def now with object
  3396 equality.  INCOMPATIBILITY.
  3397 
  3398 * Records. Removed K_record, and replaced it by pure lambda term
  3399 %x. c. The simplifier setup is now more robust against eta expansion.
  3400 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3401 
  3402 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3403 
  3404 * Library/ListVector: new theory of arithmetic vector operations.
  3405 
  3406 * Library/Order_Relation: new theory of various orderings as sets of
  3407 pairs.  Defines preorders, partial orders, linear orders and
  3408 well-orders on sets and on types.
  3409 
  3410 
  3411 *** ZF ***
  3412 
  3413 * Renamed some theories to allow to loading both ZF and HOL in the
  3414 same session:
  3415 
  3416   Datatype  -> Datatype_ZF
  3417   Inductive -> Inductive_ZF
  3418   Int       -> Int_ZF
  3419   IntDiv    -> IntDiv_ZF
  3420   Nat       -> Nat_ZF
  3421   List      -> List_ZF
  3422   Main      -> Main_ZF
  3423 
  3424 INCOMPATIBILITY: ZF theories that import individual theories below
  3425 Main might need to be adapted.  Regular theory Main is still
  3426 available, as trivial extension of Main_ZF.
  3427 
  3428 
  3429 *** ML ***
  3430 
  3431 * ML within Isar: antiquotation @{const name} or @{const
  3432 name(typargs)} produces statically-checked Const term.
  3433 
  3434 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3435 (of the same name).  Removed obsolete print command.
  3436 
  3437 * Removed obsolete "use_legacy_bindings" function.
  3438 
  3439 * The ``print mode'' is now a thread-local value derived from a global
  3440 template (the former print_mode reference), thus access becomes
  3441 non-critical.  The global print_mode reference is for session
  3442 management only; user-code should use print_mode_value,
  3443 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3444 
  3445 * Functions system/system_out provide a robust way to invoke external
  3446 shell commands, with propagation of interrupts (requires Poly/ML
  3447 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3448 
  3449 
  3450 *** System ***
  3451 
  3452 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3453 in accordance with Proof General 3.7, which prefers GNU emacs.
  3454 
  3455 * isatool tty runs Isabelle process with plain tty interaction;
  3456 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3457 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3458 
  3459 * isatool browser now works with Cygwin as well, using general
  3460 "javapath" function defined in Isabelle process environment.
  3461 
  3462 * YXML notation provides a simple and efficient alternative to
  3463 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3464 isatool yxml as described in the Isabelle system manual.
  3465 
  3466 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3467 provides general wrapper for managing an Isabelle process in a robust
  3468 fashion, with ``cooked'' output from stdin/stderr.
  3469 
  3470 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3471 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3472 
  3473 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3474 way of changing the user's settings is via
  3475 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3476 script.
  3477 
  3478 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3479 cores of the underlying machine, which is a good starting point for
  3480 optimal performance tuning.  The corresponding usedir option -M allows
  3481 "max" as an alias for "0".  WARNING: does not work on certain versions
  3482 of Mac OS (with Poly/ML 5.1).
  3483 
  3484 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3485 adverse effect of Isabelle flooding interactive front-ends (notably
  3486 ProofGeneral / XEmacs).
  3487 
  3488 
  3489 
  3490 New in Isabelle2007 (November 2007)
  3491 -----------------------------------
  3492 
  3493 *** General ***
  3494 
  3495 * More uniform information about legacy features, notably a
  3496 warning/error of "Legacy feature: ...", depending on the state of the
  3497 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3498 legacy features will disappear eventually.
  3499 
  3500 * Theory syntax: the header format ``theory A = B + C:'' has been
  3501 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3502 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3503 
  3504 * Theory syntax: the old non-Isar theory file format has been
  3505 discontinued altogether.  Note that ML proof scripts may still be used
  3506 with Isar theories; migration is usually quite simple with the ML
  3507 function use_legacy_bindings.  INCOMPATIBILITY.
  3508 
  3509 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3510 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3511 quotes.
  3512 
  3513 * Theory loader: be more serious about observing the static theory
  3514 header specifications (including optional directories), but not the
  3515 accidental file locations of previously successful loads.  The strict
  3516 update policy of former update_thy is now already performed by
  3517 use_thy, so the former has been removed; use_thys updates several
  3518 theories simultaneously, just as 'imports' within a theory header
  3519 specification, but without merging the results.  Potential
  3520 INCOMPATIBILITY: may need to refine theory headers and commands
  3521 ROOT.ML which depend on load order.
  3522 
  3523 * Theory loader: optional support for content-based file
  3524 identification, instead of the traditional scheme of full physical
  3525 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3526 (cf. the system manual).  The new scheme allows to work with
  3527 non-finished theories in persistent session images, such that source
  3528 files may be moved later on without requiring reloads.
  3529 
  3530 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3531 file (with the same base name as the theory) are considered a legacy
  3532 feature, which will disappear eventually. Even now, the theory loader
  3533 no longer maintains dependencies on such files.
  3534 
  3535 * Syntax: the scope for resolving ambiguities via type-inference is
  3536 now limited to individual terms, instead of whole simultaneous
  3537 specifications as before. This greatly reduces the complexity of the
  3538 syntax module and improves flexibility by separating parsing and
  3539 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3540 'fixes' etc.) are required in rare situations.
  3541 
  3542 * Syntax: constants introduced by new-style packages ('definition',
  3543 'abbreviation' etc.) are passed through the syntax module in
  3544 ``authentic mode''. This means that associated mixfix annotations
  3545 really stick to such constants, independently of potential name space
  3546 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3547 trees are represented slightly differently, may need to adapt syntax
  3548 translations accordingly. Use CONST marker in 'translations' and
  3549 @{const_syntax} antiquotation in 'parse_translation' etc.
  3550 
  3551 * Legacy goal package: reduced interface to the bare minimum required
  3552 to keep existing proof scripts running.  Most other user-level
  3553 functions are now part of the OldGoals structure, which is *not* open
  3554 by default (consider isatool expandshort before open OldGoals).
  3555 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3556 these tend to cause confusion about the actual goal (!) context being
  3557 used here, which is not necessarily the same as the_context().
  3558 
  3559 * Command 'find_theorems': supports "*" wild-card in "name:"
  3560 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3561 support a specific search form (see ProofGeneral/CHANGES).
  3562 
  3563 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3564 by default, which means that "prems" (and also "fixed variables") are
  3565 suppressed from proof state output.  Note that the ProofGeneral
  3566 settings mechanism allows to change and save options persistently, but
  3567 older versions of Isabelle will fail to start up if a negative prems
  3568 limit is imposed.
  3569 
  3570 * Local theory targets may be specified by non-nested blocks of
  3571 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3572 contain definitions, theorems etc., including any derived mechanism
  3573 that has been implemented on top of these primitives.  This concept
  3574 generalizes the existing ``theorem (in ...)'' towards more versatility
  3575 and scalability.
  3576 
  3577 * Proof General interface: proper undo of final 'end' command;
  3578 discontinued Isabelle/classic mode (ML proof scripts).
  3579 
  3580 
  3581 *** Document preparation ***
  3582 
  3583 * Added antiquotation @{theory name} which prints the given name,
  3584 after checking that it refers to a valid ancestor theory in the
  3585 current context.
  3586 
  3587 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3588 check the given source text as ML type/structure, printing verbatim.
  3589 
  3590 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3591 "c args == rhs" given in the current context.  (Any number of
  3592 arguments may be given on the LHS.)
  3593 
  3594 
  3595 *** Pure ***
  3596 
  3597 * The 'class' package offers a combination of axclass and locale to
  3598 achieve Haskell-like type classes in Isabelle.  Definitions and
  3599 theorems within a class context produce both relative results (with
  3600 implicit parameters according to the locale context), and polymorphic
  3601 constants with qualified polymorphism (according to the class
  3602 context).  Within the body context of a 'class' target, a separate
  3603 syntax layer ("user space type system") takes care of converting
  3604 between global polymorphic consts and internal locale representation.
  3605 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3606 "isatool doc classes" provides a tutorial.
  3607 
  3608 * Generic code generator framework allows to generate executable
  3609 code for ML and Haskell (including Isabelle classes).  A short usage
  3610 sketch:
  3611 
  3612     internal compilation:
  3613         export_code <list of constants (term syntax)> in SML
  3614     writing SML code to a file:
  3615         export_code <list of constants (term syntax)> in SML <filename>
  3616     writing OCaml code to a file:
  3617         export_code <list of constants (term syntax)> in OCaml <filename>
  3618     writing Haskell code to a bunch of files:
  3619         export_code <list of constants (term syntax)> in Haskell <filename>
  3620 
  3621     evaluating closed propositions to True/False using code generation:
  3622         method ``eval''
  3623 
  3624 Reasonable default setup of framework in HOL.
  3625 
  3626 Theorem attributs for selecting and transforming function equations theorems:
  3627 
  3628     [code fun]:        select a theorem as function equation for a specific constant
  3629     [code fun del]:    deselect a theorem as function equation for a specific constant
  3630     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3631     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3632 
  3633 User-defined serializations (target in {SML, OCaml, Haskell}):
  3634 
  3635     code_const <and-list of constants (term syntax)>
  3636       {(target) <and-list of const target syntax>}+
  3637 
  3638     code_type <and-list of type constructors>
  3639       {(target) <and-list of type target syntax>}+
  3640 
  3641     code_instance <and-list of instances>
  3642       {(target)}+
  3643         where instance ::= <type constructor> :: <class>
  3644 
  3645     code_class <and_list of classes>
  3646       {(target) <and-list of class target syntax>}+
  3647         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3648 
  3649 code_instance and code_class only are effective to target Haskell.
  3650 
  3651 For example usage see src/HOL/ex/Codegenerator.thy and
  3652 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3653 generation from Isabelle/HOL theories is available via "isatool doc
  3654 codegen".
  3655 
  3656 * Code generator: consts in 'consts_code' Isar commands are now
  3657 referred to by usual term syntax (including optional type
  3658 annotations).
  3659 
  3660 * Command 'no_translations' removes translation rules from theory
  3661 syntax.
  3662 
  3663 * Overloaded definitions are now actually checked for acyclic
  3664 dependencies.  The overloading scheme is slightly more general than
  3665 that of Haskell98, although Isabelle does not demand an exact
  3666 correspondence to type class and instance declarations.
  3667 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3668 exotic versions of overloading -- at the discretion of the user!
  3669 
  3670 Polymorphic constants are represented via type arguments, i.e. the
  3671 instantiation that matches an instance against the most general
  3672 declaration given in the signature.  For example, with the declaration
  3673 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3674 as c(nat).  Overloading is essentially simultaneous structural
  3675 recursion over such type arguments.  Incomplete specification patterns
  3676 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3677 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3678 Command 'print_theory' outputs the normalized system of recursive
  3679 equations, see section "definitions".
  3680 
  3681 * Configuration options are maintained within the theory or proof
  3682 context (with name and type bool/int/string), providing a very simple
  3683 interface to a poor-man's version of general context data.  Tools may
  3684 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3685 these values using Config.get etc.  Users may change options via an
  3686 associated attribute of the same name.  This form of context
  3687 declaration works particularly well with commands 'declare' or
  3688 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3689 very easy to avoid global references, which would not observe Isar
  3690 toplevel undo/redo and fail to work with multithreading.
  3691 
  3692 Various global ML references of Pure and HOL have been turned into
  3693 configuration options:
  3694 
  3695   Unify.search_bound		unify_search_bound
  3696   Unify.trace_bound		unify_trace_bound
  3697   Unify.trace_simp		unify_trace_simp
  3698   Unify.trace_types		unify_trace_types
  3699   Simplifier.simp_depth_limit	simp_depth_limit
  3700   Blast.depth_limit		blast_depth_limit
  3701   DatatypeProp.dtK		datatype_distinctness_limit
  3702   fast_arith_neq_limit  	fast_arith_neq_limit
  3703   fast_arith_split_limit	fast_arith_split_limit
  3704 
  3705 * Named collections of theorems may be easily installed as context
  3706 data using the functor NamedThmsFun (see also
  3707 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3708 attributes; there is also a toplevel print command.  This facility is
  3709 just a common case of general context data, which is the preferred way
  3710 for anything more complex than just a list of facts in canonical
  3711 order.
  3712 
  3713 * Isar: command 'declaration' augments a local theory by generic
  3714 declaration functions written in ML.  This enables arbitrary content
  3715 being added to the context, depending on a morphism that tells the
  3716 difference of the original declaration context wrt. the application
  3717 context encountered later on.
  3718 
  3719 * Isar: proper interfaces for simplification procedures.  Command
  3720 'simproc_setup' declares named simprocs (with match patterns, and body
  3721 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3722 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3723 
  3724 * Isar: an extra pair of brackets around attribute declarations
  3725 abbreviates a theorem reference involving an internal dummy fact,
  3726 which will be ignored later --- only the effect of the attribute on
  3727 the background context will persist.  This form of in-place
  3728 declarations is particularly useful with commands like 'declare' and
  3729 'using', for example ``have A using [[simproc a]] by simp''.
  3730 
  3731 * Isar: method "assumption" (and implicit closing of subproofs) now
  3732 takes simple non-atomic goal assumptions into account: after applying
  3733 an assumption as a rule the resulting subgoals are solved by atomic
  3734 assumption steps.  This is particularly useful to finish 'obtain'
  3735 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3736 without referring to the original premise "!!x. P x ==> thesis" in the
  3737 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3738 more permissive.
  3739 
  3740 * Isar: implicit use of prems from the Isar proof context is
  3741 considered a legacy feature.  Common applications like ``have A .''
  3742 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3743 referencing facts explicitly here improves readability and
  3744 maintainability of proof texts.
  3745 
  3746 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3747 the obtained context from the course of reasoning!  For example:
  3748 
  3749   assume "EX x y. A x & B y"   -- "any previous fact"
  3750   then guess x and y by clarify
  3751 
  3752 This technique is potentially adventurous, depending on the facts and
  3753 proof tools being involved here.
  3754 
  3755 * Isar: known facts from the proof context may be specified as literal
  3756 propositions, using ASCII back-quote syntax.  This works wherever
  3757 named facts used to be allowed so far, in proof commands, proof
  3758 methods, attributes etc.  Literal facts are retrieved from the context
  3759 according to unification of type and term parameters.  For example,
  3760 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3761 theorems in the current context, then these are valid literal facts:
  3762 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3763 
  3764 There is also a proof method "fact" which does the same composition
  3765 for explicit goal states, e.g. the following proof texts coincide with
  3766 certain special cases of literal facts:
  3767 
  3768   have "A" by fact                 ==  note `A`
  3769   have "A ==> B" by fact           ==  note `A ==> B`
  3770   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3771   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3772 
  3773 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3774 outer syntax.  Thus symbolic identifiers may be used without
  3775 additional white space in declarations like this: ``assume *: A''.
  3776 
  3777 * Isar: 'print_facts' prints all local facts of the current context,
  3778 both named and unnamed ones.
  3779 
  3780 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3781 
  3782   def x == "t" and y == "u"
  3783 
  3784 * Isar: added command 'unfolding', which is structurally similar to
  3785 'using', but affects both the goal state and facts by unfolding given
  3786 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3787 'unfolded' attribute may be replaced by first-class proof text.
  3788 
  3789 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3790 and command 'unfolding' now all support object-level equalities
  3791 (potentially conditional).  The underlying notion of rewrite rule is
  3792 analogous to the 'rule_format' attribute, but *not* that of the
  3793 Simplifier (which is usually more generous).
  3794 
  3795 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3796 premises of a theorem by n. Useful in conjunction with drule.
  3797 
  3798 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3799 method expression within a sandbox consisting of the first N
  3800 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3801 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3802 simplifies all new goals that emerge from applying rule foo to the
  3803 originally first one.
  3804 
  3805 * Isar: schematic goals are no longer restricted to higher-order
  3806 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3807 expected.
  3808 
  3809 * Isar: the conclusion of a long theorem statement is now either
  3810 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3811 (essentially a disjunction of cases with local parameters and
  3812 assumptions).  The latter allows to express general elimination rules
  3813 adequately; in this notation common elimination rules look like this:
  3814 
  3815   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3816     assumes "EX x. P x"
  3817     obtains x where "P x"
  3818 
  3819   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3820     assumes "A & B"
  3821     obtains A and B
  3822 
  3823   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3824     assumes "A | B"
  3825     obtains
  3826       A
  3827     | B
  3828 
  3829 The subsequent classical rules even refer to the formal "thesis"
  3830 explicitly:
  3831 
  3832   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3833     obtains "~ thesis"
  3834 
  3835   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3836     obtains "thesis ==> something"
  3837 
  3838 The actual proof of an 'obtains' statement is analogous to that of the
  3839 Isar proof element 'obtain', only that there may be several cases.
  3840 Optional case names may be specified in parentheses; these will be
  3841 available both in the present proof and as annotations in the
  3842 resulting rule, for later use with the 'cases' method (cf. attribute
  3843 case_names).
  3844 
  3845 * Isar: the assumptions of a long theorem statement are available as
  3846 "assms" fact in the proof context.  This is more appropriate than the
  3847 (historical) "prems", which refers to all assumptions of the current
  3848 context, including those from the target locale, proof body etc.
  3849 
  3850 * Isar: 'print_statement' prints theorems from the current theory or
  3851 proof context in long statement form, according to the syntax of a
  3852 top-level lemma.
  3853 
  3854 * Isar: 'obtain' takes an optional case name for the local context
  3855 introduction rule (default "that").
  3856 
  3857 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3858 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3859 to occur.
  3860 
  3861 * Pure: syntax "CONST name" produces a fully internalized constant
  3862 according to the current context.  This is particularly useful for
  3863 syntax translations that should refer to internal constant
  3864 representations independently of name spaces.
  3865 
  3866 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3867 instead of "FOO ". This allows multiple binder declarations to coexist
  3868 in the same context.  INCOMPATIBILITY.
  3869 
  3870 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3871 primitive that also works in a locale context (both for constants and
  3872 fixed variables). Type declaration and internal syntactic representation
  3873 of given constants retrieved from the context. Likewise, the
  3874 'no_notation' command allows to remove given syntax annotations from the
  3875 current context.
  3876 
  3877 * Isar/locales: new derived specification elements 'axiomatization',
  3878 'definition', 'abbreviation', which support type-inference, admit
  3879 object-level specifications (equality, equivalence).  See also the
  3880 isar-ref manual.  Examples:
  3881 
  3882   axiomatization
  3883     eq  (infix "===" 50) where
  3884     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3885 
  3886   definition "f x y = x + y + 1"
  3887   definition g where "g x = f x x"
  3888 
  3889   abbreviation
  3890     neq  (infix "=!=" 50) where
  3891     "x =!= y == ~ (x === y)"
  3892 
  3893 These specifications may be also used in a locale context.  Then the
  3894 constants being introduced depend on certain fixed parameters, and the
  3895 constant name is qualified by the locale base name.  An internal
  3896 abbreviation takes care for convenient input and output, making the
  3897 parameters implicit and using the original short name.  See also
  3898 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3899 entities from a monomorphic theory.
  3900 
  3901 Presently, abbreviations are only available 'in' a target locale, but
  3902 not inherited by general import expressions.  Also note that
  3903 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3904 'translations' in common applications.  The "no_abbrevs" print mode
  3905 prevents folding of abbreviations in term output.
  3906 
  3907 Concrete syntax is attached to specified constants in internal form,
  3908 independently of name spaces.  The parse tree representation is
  3909 slightly different -- use 'notation' instead of raw 'syntax', and
  3910 'translations' with explicit "CONST" markup to accommodate this.
  3911 
  3912 * Pure/Isar: unified syntax for new-style specification mechanisms
  3913 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3914 full type inference and dummy patterns ("_").  For example:
  3915 
  3916   definition "K x _ = x"
  3917 
  3918   inductive conj for A B
  3919   where "A ==> B ==> conj A B"
  3920 
  3921 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3922 the current context.  Print mode "no_abbrevs" prevents inversion of
  3923 abbreviations on output.
  3924 
  3925 * Isar/locales: improved parameter handling: use of locales "var" and
  3926 "struct" no longer necessary; - parameter renamings are no longer
  3927 required to be injective.  For example, this allows to define
  3928 endomorphisms as locale endom = homom mult mult h.
  3929 
  3930 * Isar/locales: changed the way locales with predicates are defined.
  3931 Instead of accumulating the specification, the imported expression is
  3932 now an interpretation.  INCOMPATIBILITY: different normal form of
  3933 locale expressions.  In particular, in interpretations of locales with
  3934 predicates, goals repesenting already interpreted fragments are not
  3935 removed automatically.  Use methods `intro_locales' and
  3936 `unfold_locales'; see below.
  3937 
  3938 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3939 provide backward reasoning on locales predicates.  The methods are
  3940 aware of interpretations and discharge corresponding goals.
  3941 `intro_locales' is less aggressive then `unfold_locales' and does not
  3942 unfold predicates to assumptions.
  3943 
  3944 * Isar/locales: the order in which locale fragments are accumulated
  3945 has changed.  This enables to override declarations from fragments due
  3946 to interpretations -- for example, unwanted simp rules.
  3947 
  3948 * Isar/locales: interpretation in theories and proof contexts has been
  3949 extended.  One may now specify (and prove) equations, which are
  3950 unfolded in interpreted theorems.  This is useful for replacing
  3951 defined concepts (constants depending on locale parameters) by
  3952 concepts already existing in the target context.  Example:
  3953 
  3954   interpretation partial_order ["op <= :: [int, int] => bool"]
  3955     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3956 
  3957 Typically, the constant `partial_order.less' is created by a
  3958 definition specification element in the context of locale
  3959 partial_order.
  3960 
  3961 * Method "induct": improved internal context management to support
  3962 local fixes and defines on-the-fly. Thus explicit meta-level
  3963 connectives !!  and ==> are rarely required anymore in inductive goals
  3964 (using object-logic connectives for this purpose has been long
  3965 obsolete anyway). Common proof patterns are explained in
  3966 src/HOL/Induct/Common_Patterns.thy, see also
  3967 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3968 examples.
  3969 
  3970 * Method "induct": improved handling of simultaneous goals. Instead of
  3971 introducing object-level conjunction, the statement is now split into
  3972 several conclusions, while the corresponding symbolic cases are nested
  3973 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3974 see src/HOL/Induct/Common_Patterns.thy, for example.
  3975 
  3976 * Method "induct": mutual induction rules are now specified as a list
  3977 of rule sharing the same induction cases. HOL packages usually provide
  3978 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3979 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3980 mutual induction rules differently, i.e. like this:
  3981 
  3982   (induct rule: foo_bar.inducts)
  3983   (induct set: foo bar)
  3984   (induct pred: foo bar)
  3985   (induct type: foo bar)
  3986 
  3987 The ML function ProjectRule.projections turns old-style rules into the
  3988 new format.
  3989 
  3990 * Method "coinduct": dual of induction, see
  3991 src/HOL/Library/Coinductive_List.thy for various examples.
  3992 
  3993 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3994 considered a legacy feature.
  3995 
  3996 * Attribute "symmetric" produces result with standardized schematic
  3997 variables (index 0).  Potential INCOMPATIBILITY.
  3998 
  3999 * Simplifier: by default the simplifier trace only shows top level
  4000 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  4001 default. Thus there is less danger of being flooded by the trace. The
  4002 trace indicates where parts have been suppressed.
  4003   
  4004 * Provers/classical: removed obsolete classical version of elim_format
  4005 attribute; classical elim/dest rules are now treated uniformly when
  4006 manipulating the claset.
  4007 
  4008 * Provers/classical: stricter checks to ensure that supplied intro,
  4009 dest and elim rules are well-formed; dest and elim rules must have at
  4010 least one premise.
  4011 
  4012 * Provers/classical: attributes dest/elim/intro take an optional
  4013 weight argument for the rule (just as the Pure versions).  Weights are
  4014 ignored by automated tools, but determine the search order of single
  4015 rule steps.
  4016 
  4017 * Syntax: input syntax now supports dummy variable binding "%_. b",
  4018 where the body does not mention the bound variable.  Note that dummy
  4019 patterns implicitly depend on their context of bounds, which makes
  4020 "{_. _}" match any set comprehension as expected.  Potential
  4021 INCOMPATIBILITY -- parse translations need to cope with syntactic
  4022 constant "_idtdummy" in the binding position.
  4023 
  4024 * Syntax: removed obsolete syntactic constant "_K" and its associated
  4025 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  4026 for example "A -> B" => "Pi A (%_. B)".
  4027 
  4028 * Pure: 'class_deps' command visualizes the subclass relation, using
  4029 the graph browser tool.
  4030 
  4031 * Pure: 'print_theory' now suppresses certain internal declarations by
  4032 default; use '!' option for full details.
  4033 
  4034 
  4035 *** HOL ***
  4036 
  4037 * Method "metis" proves goals by applying the Metis general-purpose
  4038 resolution prover (see also http://gilith.com/software/metis/).
  4039 Examples are in the directory MetisExamples.  WARNING: the
  4040 Isabelle/HOL-Metis integration does not yet work properly with
  4041 multi-threading.
  4042   
  4043 * Command 'sledgehammer' invokes external automatic theorem provers as
  4044 background processes.  It generates calls to the "metis" method if
  4045 successful. These can be pasted into the proof.  Users do not have to
  4046 wait for the automatic provers to return.  WARNING: does not really
  4047 work with multi-threading.
  4048 
  4049 * New "auto_quickcheck" feature tests outermost goal statements for
  4050 potential counter-examples.  Controlled by ML references
  4051 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  4052 5000 milliseconds).  Fails silently if statements is outside of
  4053 executable fragment, or any other codgenerator problem occurs.
  4054 
  4055 * New constant "undefined" with axiom "undefined x = undefined".
  4056 
  4057 * Added class "HOL.eq", allowing for code generation with polymorphic
  4058 equality.
  4059 
  4060 * Some renaming of class constants due to canonical name prefixing in
  4061 the new 'class' package:
  4062 
  4063     HOL.abs ~> HOL.abs_class.abs
  4064     HOL.divide ~> HOL.divide_class.divide
  4065     0 ~> HOL.zero_class.zero
  4066     1 ~> HOL.one_class.one
  4067     op + ~> HOL.plus_class.plus
  4068     op - ~> HOL.minus_class.minus
  4069     uminus ~> HOL.minus_class.uminus
  4070     op * ~> HOL.times_class.times
  4071     op < ~> HOL.ord_class.less
  4072     op <= > HOL.ord_class.less_eq
  4073     Nat.power ~> Power.power_class.power
  4074     Nat.size ~> Nat.size_class.size
  4075     Numeral.number_of ~> Numeral.number_class.number_of
  4076     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  4077     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  4078     Orderings.min ~> Orderings.ord_class.min
  4079     Orderings.max ~> Orderings.ord_class.max
  4080     Divides.op div ~> Divides.div_class.div
  4081     Divides.op mod ~> Divides.div_class.mod
  4082     Divides.op dvd ~> Divides.div_class.dvd
  4083 
  4084 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  4085 
  4086 a) User-defined constants using any of the names "plus", "minus",
  4087 "times", "less" or "less_eq". The standard syntax translations for
  4088 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  4089 names.
  4090 
  4091 b) Variables named "plus", "minus", "times", "less", "less_eq"
  4092 INCOMPATIBILITY: use more specific names.
  4093 
  4094 c) Permutative equations (e.g. "a + b = b + a")
  4095 Since the change of names also changes the order of terms, permutative
  4096 rewrite rules may get applied in a different order. Experience shows
  4097 that this is rarely the case (only two adaptions in the whole Isabelle
  4098 distribution).  INCOMPATIBILITY: rewrite proofs
  4099 
  4100 d) ML code directly refering to constant names
  4101 This in general only affects hand-written proof tactics, simprocs and
  4102 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4103 Consider using @{const_name} antiquotation.
  4104 
  4105 * New class "default" with associated constant "default".
  4106 
  4107 * Function "sgn" is now overloaded and available on int, real, complex
  4108 (and other numeric types), using class "sgn".  Two possible defs of
  4109 sgn are given as equational assumptions in the classes sgn_if and
  4110 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4111 INCOMPATIBILITY.
  4112 
  4113 * Locale "partial_order" now unified with class "order" (cf. theory
  4114 Orderings), added parameter "less".  INCOMPATIBILITY.
  4115 
  4116 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4117 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4118 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4119 
  4120 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4121 changed order of proof goals in instance proofs.
  4122 
  4123 * The transitivity reasoner for partial and linear orders is set up
  4124 for classes "order" and "linorder".  Instances of the reasoner are available
  4125 in all contexts importing or interpreting the corresponding locales.
  4126 Method "order" invokes the reasoner separately; the reasoner
  4127 is also integrated with the Simplifier as a solver.  Diagnostic
  4128 command 'print_orders' shows the available instances of the reasoner
  4129 in the current context.
  4130 
  4131 * Localized monotonicity predicate in theory "Orderings"; integrated
  4132 lemmas max_of_mono and min_of_mono with this predicate.
  4133 INCOMPATIBILITY.
  4134 
  4135 * Formulation of theorem "dense" changed slightly due to integration
  4136 with new class dense_linear_order.
  4137 
  4138 * Uniform lattice theory development in HOL.
  4139 
  4140     constants "meet" and "join" now named "inf" and "sup"
  4141     constant "Meet" now named "Inf"
  4142 
  4143     classes "meet_semilorder" and "join_semilorder" now named
  4144       "lower_semilattice" and "upper_semilattice"
  4145     class "lorder" now named "lattice"
  4146     class "comp_lat" now named "complete_lattice"
  4147 
  4148     Instantiation of lattice classes allows explicit definitions
  4149     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4150 
  4151   INCOMPATIBILITY.  Theorem renames:
  4152 
  4153     meet_left_le            ~> inf_le1
  4154     meet_right_le           ~> inf_le2
  4155     join_left_le            ~> sup_ge1
  4156     join_right_le           ~> sup_ge2
  4157     meet_join_le            ~> inf_sup_ord
  4158     le_meetI                ~> le_infI
  4159     join_leI                ~> le_supI
  4160     le_meet                 ~> le_inf_iff
  4161     le_join                 ~> ge_sup_conv
  4162     meet_idempotent         ~> inf_idem
  4163     join_idempotent         ~> sup_idem
  4164     meet_comm               ~> inf_commute
  4165     join_comm               ~> sup_commute
  4166     meet_leI1               ~> le_infI1
  4167     meet_leI2               ~> le_infI2
  4168     le_joinI1               ~> le_supI1
  4169     le_joinI2               ~> le_supI2
  4170     meet_assoc              ~> inf_assoc
  4171     join_assoc              ~> sup_assoc
  4172     meet_left_comm          ~> inf_left_commute
  4173     meet_left_idempotent    ~> inf_left_idem
  4174     join_left_comm          ~> sup_left_commute
  4175     join_left_idempotent    ~> sup_left_idem
  4176     meet_aci                ~> inf_aci
  4177     join_aci                ~> sup_aci
  4178     le_def_meet             ~> le_iff_inf
  4179     le_def_join             ~> le_iff_sup
  4180     join_absorp2            ~> sup_absorb2
  4181     join_absorp1            ~> sup_absorb1
  4182     meet_absorp1            ~> inf_absorb1
  4183     meet_absorp2            ~> inf_absorb2
  4184     meet_join_absorp        ~> inf_sup_absorb
  4185     join_meet_absorp        ~> sup_inf_absorb
  4186     distrib_join_le         ~> distrib_sup_le
  4187     distrib_meet_le         ~> distrib_inf_le
  4188 
  4189     add_meet_distrib_left   ~> add_inf_distrib_left
  4190     add_join_distrib_left   ~> add_sup_distrib_left
  4191     is_join_neg_meet        ~> is_join_neg_inf
  4192     is_meet_neg_join        ~> is_meet_neg_sup
  4193     add_meet_distrib_right  ~> add_inf_distrib_right
  4194     add_join_distrib_right  ~> add_sup_distrib_right
  4195     add_meet_join_distribs  ~> add_sup_inf_distribs
  4196     join_eq_neg_meet        ~> sup_eq_neg_inf
  4197     meet_eq_neg_join        ~> inf_eq_neg_sup
  4198     add_eq_meet_join        ~> add_eq_inf_sup
  4199     meet_0_imp_0            ~> inf_0_imp_0
  4200     join_0_imp_0            ~> sup_0_imp_0
  4201     meet_0_eq_0             ~> inf_0_eq_0
  4202     join_0_eq_0             ~> sup_0_eq_0
  4203     neg_meet_eq_join        ~> neg_inf_eq_sup
  4204     neg_join_eq_meet        ~> neg_sup_eq_inf
  4205     join_eq_if              ~> sup_eq_if
  4206 
  4207     mono_meet               ~> mono_inf
  4208     mono_join               ~> mono_sup
  4209     meet_bool_eq            ~> inf_bool_eq
  4210     join_bool_eq            ~> sup_bool_eq
  4211     meet_fun_eq             ~> inf_fun_eq
  4212     join_fun_eq             ~> sup_fun_eq
  4213     meet_set_eq             ~> inf_set_eq
  4214     join_set_eq             ~> sup_set_eq
  4215     meet1_iff               ~> inf1_iff
  4216     meet2_iff               ~> inf2_iff
  4217     meet1I                  ~> inf1I
  4218     meet2I                  ~> inf2I
  4219     meet1D1                 ~> inf1D1
  4220     meet2D1                 ~> inf2D1
  4221     meet1D2                 ~> inf1D2
  4222     meet2D2                 ~> inf2D2
  4223     meet1E                  ~> inf1E
  4224     meet2E                  ~> inf2E
  4225     join1_iff               ~> sup1_iff
  4226     join2_iff               ~> sup2_iff
  4227     join1I1                 ~> sup1I1
  4228     join2I1                 ~> sup2I1
  4229     join1I1                 ~> sup1I1
  4230     join2I2                 ~> sup1I2
  4231     join1CI                 ~> sup1CI
  4232     join2CI                 ~> sup2CI
  4233     join1E                  ~> sup1E
  4234     join2E                  ~> sup2E
  4235 
  4236     is_meet_Meet            ~> is_meet_Inf
  4237     Meet_bool_def           ~> Inf_bool_def
  4238     Meet_fun_def            ~> Inf_fun_def
  4239     Meet_greatest           ~> Inf_greatest
  4240     Meet_lower              ~> Inf_lower
  4241     Meet_set_def            ~> Inf_set_def
  4242 
  4243     Sup_def                 ~> Sup_Inf
  4244     Sup_bool_eq             ~> Sup_bool_def
  4245     Sup_fun_eq              ~> Sup_fun_def
  4246     Sup_set_eq              ~> Sup_set_def
  4247 
  4248     listsp_meetI            ~> listsp_infI
  4249     listsp_meet_eq          ~> listsp_inf_eq
  4250 
  4251     meet_min                ~> inf_min
  4252     join_max                ~> sup_max
  4253 
  4254 * Added syntactic class "size"; overloaded constant "size" now has
  4255 type "'a::size ==> bool"
  4256 
  4257 * Internal reorganisation of `size' of datatypes: size theorems
  4258 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4259 simplification rules by default!); theorems "prod.size" now named
  4260 "*.size".
  4261 
  4262 * Class "div" now inherits from class "times" rather than "type".
  4263 INCOMPATIBILITY.
  4264 
  4265 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4266 Linorder etc.  have disappeared; operations defined in terms of
  4267 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4268 
  4269 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4270 
  4271 * HOL-Word: New extensive library and type for generic, fixed size
  4272 machine words, with arithemtic, bit-wise, shifting and rotating
  4273 operations, reflection into int, nat, and bool lists, automation for
  4274 linear arithmetic (by automatic reflection into nat or int), including
  4275 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4276 arithmetic type classes, supporting automatic simplification of
  4277 numerals on all operations.
  4278 
  4279 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4280 
  4281 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4282 
  4283 * Code generator library theories:
  4284   - Code_Integer represents HOL integers by big integer literals in target
  4285     languages.
  4286   - Code_Char represents HOL characters by character literals in target
  4287     languages.
  4288   - Code_Char_chr like Code_Char, but also offers treatment of character
  4289     codes; includes Code_Integer.
  4290   - Executable_Set allows to generate code for finite sets using lists.
  4291   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4292     denominator).
  4293   - Executable_Real implements a subset of real numbers, namly those
  4294     representable by rational numbers.
  4295   - Efficient_Nat implements natural numbers by integers, which in general will
  4296     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4297     includes Code_Integer.
  4298   - Code_Index provides an additional datatype index which is mapped to
  4299     target-language built-in integers.
  4300   - Code_Message provides an additional datatype message_string which is isomorphic to
  4301     strings; messages are mapped to target-language strings.
  4302 
  4303 * New package for inductive predicates
  4304 
  4305   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4306 
  4307     inductive
  4308       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4309       for z_1 :: U_1 and ... and z_n :: U_m
  4310     where
  4311       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4312     | ...
  4313 
  4314   with full support for type-inference, rather than
  4315 
  4316     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4317 
  4318     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4319     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4320 
  4321     inductive "s z_1 ... z_m"
  4322     intros
  4323       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4324       ...
  4325 
  4326   For backward compatibility, there is a wrapper allowing inductive
  4327   sets to be defined with the new package via
  4328 
  4329     inductive_set
  4330       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4331       for z_1 :: U_1 and ... and z_n :: U_m
  4332     where
  4333       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4334     | ...
  4335 
  4336   or
  4337 
  4338     inductive_set
  4339       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4340       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4341       for z_1 :: U_1 and ... and z_n :: U_m
  4342     where
  4343       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4344     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4345     | ...
  4346 
  4347   if the additional syntax "p ..." is required.
  4348 
  4349   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4350   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4351 
  4352   INCOMPATIBILITIES:
  4353 
  4354   - Since declaration and definition of inductive sets or predicates
  4355     is no longer separated, abbreviations involving the newly
  4356     introduced sets or predicates must be specified together with the
  4357     introduction rules after the 'where' keyword (see above), rather
  4358     than before the actual inductive definition.
  4359 
  4360   - The variables in induction and elimination rules are now
  4361     quantified in the order of their occurrence in the introduction
  4362     rules, rather than in alphabetical order. Since this may break
  4363     some proofs, these proofs either have to be repaired, e.g. by
  4364     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4365     statements of the form
  4366 
  4367       case (rule_i a_i_1 ... a_i_{k_i})
  4368 
  4369     or the old order of quantification has to be restored by explicitly adding
  4370     meta-level quantifiers in the introduction rules, i.e.
  4371 
  4372       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4373 
  4374   - The format of the elimination rules is now
  4375 
  4376       p z_1 ... z_m x_1 ... x_n ==>
  4377         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4378         ==> ... ==> P
  4379 
  4380     for predicates and
  4381 
  4382       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4383         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4384         ==> ... ==> P
  4385 
  4386     for sets rather than
  4387 
  4388       x : s z_1 ... z_m ==>
  4389         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4390         ==> ... ==> P
  4391 
  4392     This may require terms in goals to be expanded to n-tuples
  4393     (e.g. using case_tac or simplification with the split_paired_all
  4394     rule) before the above elimination rule is applicable.
  4395 
  4396   - The elimination or case analysis rules for (mutually) inductive
  4397     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4398     list of rules "p_1_..._p_k.elims" is no longer available.
  4399 
  4400 * New package "function"/"fun" for general recursive functions,
  4401 supporting mutual and nested recursion, definitions in local contexts,
  4402 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4403 for small examples, and the separate tutorial on the function
  4404 package. The old recdef "package" is still available as before, but
  4405 users are encouraged to use the new package.
  4406 
  4407 * Method "lexicographic_order" automatically synthesizes termination
  4408 relations as lexicographic combinations of size measures. 
  4409 
  4410 * Case-expressions allow arbitrary constructor-patterns (including
  4411 "_") and take their order into account, like in functional
  4412 programming.  Internally, this is translated into nested
  4413 case-expressions; missing cases are added and mapped to the predefined
  4414 constant "undefined". In complicated cases printing may no longer show
  4415 the original input but the internal form. Lambda-abstractions allow
  4416 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4417 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4418 variable.
  4419 
  4420 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4421 is an abbreviation for "of_nat :: nat => int". The simplification
  4422 rules for "of_nat" have been changed to work like "int" did
  4423 previously.  Potential INCOMPATIBILITY:
  4424   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4425   - of_nat_diff and of_nat_mult are no longer default simp rules
  4426 
  4427 * Method "algebra" solves polynomial equations over (semi)rings using
  4428 Groebner bases. The (semi)ring structure is defined by locales and the
  4429 tool setup depends on that generic context. Installing the method for
  4430 a specific type involves instantiating the locale and possibly adding
  4431 declarations for computation on the coefficients.  The method is
  4432 already instantiated for natural numbers and for the axiomatic class
  4433 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4434 CALCULEMUS 2007 for the general principles underlying this
  4435 architecture of context-aware proof-tools.
  4436 
  4437 * Method "ferrack" implements quantifier elimination over
  4438 special-purpose dense linear orders using locales (analogous to
  4439 "algebra"). The method is already installed for class
  4440 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4441 rat, etc.
  4442 
  4443 * Former constant "List.op @" now named "List.append".  Use ML
  4444 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4445 circumvent possible incompatibilities when working on ML level.
  4446 
  4447 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4448 
  4449 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4450 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4451 
  4452 * New syntax for Haskell-like list comprehension (input only), eg.
  4453 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4454 
  4455 * The special syntax for function "filter" has changed from [x :
  4456 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4457 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4458 
  4459 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4460 defined on nat only, as an abbreviation for [a..<Suc b]
  4461 INCOMPATIBILITY.
  4462 
  4463 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4464 
  4465 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4466 
  4467 * New lemma collection field_simps (an extension of ring_simps) for
  4468 manipulating (in)equations involving division. Multiplies with all
  4469 denominators that can be proved to be non-zero (in equations) or
  4470 positive/negative (in inequations).
  4471 
  4472 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4473 have been improved and renamed to ring_simps, group_simps and
  4474 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4475 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4476 
  4477 * Theory Library/Commutative_Ring: switched from recdef to function
  4478 package; constants add, mul, pow now curried.  Infix syntax for
  4479 algebraic operations.
  4480 
  4481 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4482 INCOMPATIBILITY.
  4483 
  4484 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4485 INCOMPATIBILITY.
  4486 
  4487 * HOL/records: generalised field-update to take a function on the
  4488 field rather than the new value: r(|A := x|) is translated to A_update
  4489 (K x) r The K-combinator that is internally used is called K_record.
  4490 INCOMPATIBILITY: Usage of the plain update functions has to be
  4491 adapted.
  4492  
  4493 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4494 * x = 0, which are required for a semiring.  Richer structures do not
  4495 inherit from semiring_0 anymore, because this property is a theorem
  4496 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4497 there is more to prove, but this is mostly trivial.
  4498 
  4499 * Class "recpower" is generalized to arbitrary monoids, not just
  4500 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4501 commutativity or semiring properties additionally.
  4502 
  4503 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4504 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4505 better use 'abbreviation'.
  4506 
  4507 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4508 
  4509 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4510 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4511 significant changes for setting up numeral syntax for types:
  4512   - New constants Numeral.pred and Numeral.succ instead
  4513       of former Numeral.bin_pred and Numeral.bin_succ.
  4514   - Use integer operations instead of bin_add, bin_mult and so on.
  4515   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4516   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4517 
  4518 See src/HOL/Integ/IntArith.thy for an example setup.
  4519 
  4520 * Command 'normal_form' computes the normal form of a term that may
  4521 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4522 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4523 heavy-duty computations because the functions are compiled to ML
  4524 first.  Correspondingly, a method "normalization" is provided.  See
  4525 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4526 
  4527 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4528 25 like -->); output depends on the "iff" print_mode, the default is
  4529 "A = B" (with priority 50).
  4530 
  4531 * Relations less (<) and less_eq (<=) are also available on type bool.
  4532 Modified syntax to disallow nesting without explicit parentheses,
  4533 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4534 INCOMPATIBILITY.
  4535 
  4536 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4537 
  4538 * Relation composition operator "op O" now has precedence 75 and binds
  4539 stronger than union and intersection. INCOMPATIBILITY.
  4540 
  4541 * The old set interval syntax "{m..n(}" (and relatives) has been
  4542 removed.  Use "{m..<n}" (and relatives) instead.
  4543 
  4544 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4545 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4546 ``declare [[simproc del: neq]]''.
  4547 
  4548 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4549 True/False.
  4550 
  4551 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4552 
  4553 * Theorem setsum_mult renamed to setsum_right_distrib.
  4554 
  4555 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4556 ``rule'' method.
  4557 
  4558 * Reimplemented methods "sat" and "satx", with several improvements:
  4559 goals no longer need to be stated as "<prems> ==> False", equivalences
  4560 (i.e. "=" on type bool) are handled, variable names of the form
  4561 "lit_<n>" are no longer reserved, significant speedup.
  4562 
  4563 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4564 zChaff is still supported as well.
  4565 
  4566 * 'inductive' and 'datatype': provide projections of mutual rules,
  4567 bundled as foo_bar.inducts;
  4568 
  4569 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4570 Library.
  4571 
  4572 * Library: moved theory Accessible_Part to main HOL.
  4573 
  4574 * Library: added theory Coinductive_List of potentially infinite lists
  4575 as greatest fixed-point.
  4576 
  4577 * Library: added theory AssocList which implements (finite) maps as
  4578 association lists.
  4579 
  4580 * Method "evaluation" solves goals (i.e. a boolean expression)
  4581 efficiently by compiling it to ML.  The goal is "proved" (via an
  4582 oracle) if it evaluates to True.
  4583 
  4584 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4585 also when invoked by the simplifier.  This results in the Simplifier
  4586 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4587 Configuration option fast_arith_split_limit=0 recovers the old
  4588 behavior.
  4589 
  4590 * Support for hex (0x20) and binary (0b1001) numerals.
  4591 
  4592 * New method: reify eqs (t), where eqs are equations for an
  4593 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4594 parameter, computes a term s::'b and a list xs::'a list and proves the
  4595 theorem I xs s = t. This is also known as reification or quoting. The
  4596 resulting theorem is applied to the subgoal to substitute t with I xs
  4597 s.  If t is omitted, the subgoal itself is reified.
  4598 
  4599 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4600 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4601 where f is supposed to be a computable function (in the sense of code
  4602 generattion). The method uses reify to compute s and xs as above then
  4603 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4604 r and finally gets the theorem t = r, which is again applied to the
  4605 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4606 
  4607 * Reflection: Automatic reification now handels binding, an example is
  4608 available in src/HOL/ex/ReflectionEx.thy
  4609 
  4610 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4611 command 'statespace' that is similar to 'record', but introduces an
  4612 abstract specification based on the locale infrastructure instead of
  4613 HOL types.  This leads to extra flexibility in composing state spaces,
  4614 in particular multiple inheritance and renaming of components.
  4615 
  4616 
  4617 *** HOL-Complex ***
  4618 
  4619 * Hyperreal: Functions root and sqrt are now defined on negative real
  4620 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4621 Nonnegativity side conditions have been removed from many lemmas, so
  4622 that more subgoals may now be solved by simplification; potential
  4623 INCOMPATIBILITY.
  4624 
  4625 * Real: new type classes formalize real normed vector spaces and
  4626 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4627 and norm :: 'a => real.
  4628 
  4629 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4630 reals into other types. The overloaded constant Reals :: 'a set is now
  4631 defined as range of_real; potential INCOMPATIBILITY.
  4632 
  4633 * Real: proper support for ML code generation, including 'quickcheck'.
  4634 Reals are implemented as arbitrary precision rationals.
  4635 
  4636 * Hyperreal: Several constants that previously worked only for the
  4637 reals have been generalized, so they now work over arbitrary vector
  4638 spaces. Type annotations may need to be added in some cases; potential
  4639 INCOMPATIBILITY.
  4640 
  4641   Infinitesimal  :: ('a::real_normed_vector) star set
  4642   HFinite        :: ('a::real_normed_vector) star set
  4643   HInfinite      :: ('a::real_normed_vector) star set
  4644   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4645   monad          :: ('a::real_normed_vector) star => 'a star set
  4646   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4647   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4648   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4649   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4650   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4651   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4652   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4653   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4654   sgn            :: 'a::real_normed_vector => 'a
  4655   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4656 
  4657 * Complex: Some complex-specific constants are now abbreviations for
  4658 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4659 hnorm.  Other constants have been entirely removed in favor of the
  4660 polymorphic versions (INCOMPATIBILITY):
  4661 
  4662   approx        <-- capprox
  4663   HFinite       <-- CFinite
  4664   HInfinite     <-- CInfinite
  4665   Infinitesimal <-- CInfinitesimal
  4666   monad         <-- cmonad
  4667   galaxy        <-- cgalaxy
  4668   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4669   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4670   (ns)deriv     <-- (ns)cderiv
  4671 
  4672 
  4673 *** HOL-Algebra ***
  4674 
  4675 * Formalisation of ideals and the quotient construction over rings.
  4676 
  4677 * Order and lattice theory no longer based on records.
  4678 INCOMPATIBILITY.
  4679 
  4680 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4681 greatest_closed.  INCOMPATIBILITY.
  4682 
  4683 * Method algebra is now set up via an attribute.  For examples see
  4684 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4685 of algebraic structures.
  4686 
  4687 * Renamed theory CRing to Ring.
  4688 
  4689 
  4690 *** HOL-Nominal ***
  4691 
  4692 * Substantial, yet incomplete support for nominal datatypes (binding
  4693 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4694 src/HOL/Nominal/Examples.  Prospective users should consult
  4695 http://isabelle.in.tum.de/nominal/
  4696 
  4697 
  4698 *** ML ***
  4699 
  4700 * ML basics: just one true type int, which coincides with IntInf.int
  4701 (even on SML/NJ).
  4702 
  4703 * ML within Isar: antiquotations allow to embed statically-checked
  4704 formal entities in the source, referring to the context available at
  4705 compile-time.  For example:
  4706 
  4707 ML {* @{sort "{zero,one}"} *}
  4708 ML {* @{typ "'a => 'b"} *}
  4709 ML {* @{term "%x. x"} *}
  4710 ML {* @{prop "x == y"} *}
  4711 ML {* @{ctyp "'a => 'b"} *}
  4712 ML {* @{cterm "%x. x"} *}
  4713 ML {* @{cprop "x == y"} *}
  4714 ML {* @{thm asm_rl} *}
  4715 ML {* @{thms asm_rl} *}
  4716 ML {* @{type_name c} *}
  4717 ML {* @{type_syntax c} *}
  4718 ML {* @{const_name c} *}
  4719 ML {* @{const_syntax c} *}
  4720 ML {* @{context} *}
  4721 ML {* @{theory} *}
  4722 ML {* @{theory Pure} *}
  4723 ML {* @{theory_ref} *}
  4724 ML {* @{theory_ref Pure} *}
  4725 ML {* @{simpset} *}
  4726 ML {* @{claset} *}
  4727 ML {* @{clasimpset} *}
  4728 
  4729 The same works for sources being ``used'' within an Isar context.
  4730 
  4731 * ML in Isar: improved error reporting; extra verbosity with
  4732 ML_Context.trace enabled.
  4733 
  4734 * Pure/General/table.ML: the join operations now works via exceptions
  4735 DUP/SAME instead of type option. This is simpler in simple cases, and
  4736 admits slightly more efficient complex applications.
  4737 
  4738 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4739 use Context.generic instead of just theory.
  4740 
  4741 * Pure: datatype Context.generic joins theory/Proof.context and
  4742 provides some facilities for code that works in either kind of
  4743 context, notably GenericDataFun for uniform theory and proof data.
  4744 
  4745 * Pure: simplified internal attribute type, which is now always
  4746 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4747 local (Proof.context) attributes have been discontinued, while
  4748 minimizing code duplication. Thm.rule_attribute and
  4749 Thm.declaration_attribute build canonical attributes; see also structure
  4750 Context for further operations on Context.generic, notably
  4751 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4752 declarations and definitions.
  4753 
  4754 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4755 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4756 init only required for impure data. INCOMPATIBILITY: empty really need
  4757 to be empty (no dependencies on theory content!)
  4758 
  4759 * Pure/kernel: consts certification ignores sort constraints given in
  4760 signature declarations. (This information is not relevant to the
  4761 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4762 potential INCOMPATIBILITY.
  4763 
  4764 * Pure: axiomatic type classes are now purely definitional, with
  4765 explicit proofs of class axioms and super class relations performed
  4766 internally. See Pure/axclass.ML for the main internal interfaces --
  4767 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4768 AxClass.axiomatize_class/classrel/arity supersede
  4769 Sign.add_classes/classrel/arities.
  4770 
  4771 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4772 global/local versions on theory vs. Proof.context have been
  4773 discontinued; Attrib.syntax and Method.syntax have been adapted
  4774 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4775 attributes, methods, etc.
  4776 
  4777 * Pure: several functions of signature "... -> theory -> theory * ..."
  4778 have been reoriented to "... -> theory -> ... * theory" in order to
  4779 allow natural usage in combination with the ||>, ||>>, |-> and
  4780 fold_map combinators.
  4781 
  4782 * Pure: official theorem names (closed derivations) and additional
  4783 comments (tags) are now strictly separate.  Name hints -- which are
  4784 maintained as tags -- may be attached any time without affecting the
  4785 derivation.
  4786 
  4787 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4788 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4789 achieve the old behaviour.
  4790 
  4791 * Pure: the "Goal" constant is now called "prop", supporting a
  4792 slightly more general idea of ``protecting'' meta-level rule
  4793 statements.
  4794 
  4795 * Pure: Logic.(un)varify only works in a global context, which is now
  4796 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4797 Logic.legacy_(un)varify as temporary workaround.
  4798 
  4799 * Pure: structure Name provides scalable operations for generating
  4800 internal variable names, notably Name.variants etc.  This replaces
  4801 some popular functions from term.ML:
  4802 
  4803   Term.variant		->  Name.variant
  4804   Term.variantlist	->  Name.variant_list
  4805   Term.invent_names	->  Name.invent_list
  4806 
  4807 Note that low-level renaming rarely occurs in new code -- operations
  4808 from structure Variable are used instead (see below).
  4809 
  4810 * Pure: structure Variable provides fundamental operations for proper
  4811 treatment of fixed/schematic variables in a context.  For example,
  4812 Variable.import introduces fixes for schematics of given facts and
  4813 Variable.export reverses the effect (up to renaming) -- this replaces
  4814 various freeze_thaw operations.
  4815 
  4816 * Pure: structure Goal provides simple interfaces for
  4817 init/conclude/finish and tactical prove operations (replacing former
  4818 Tactic.prove).  Goal.prove is the canonical way to prove results
  4819 within a given context; Goal.prove_global is a degraded version for
  4820 theory level goals, including a global Drule.standard.  Note that
  4821 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4822 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4823 in a locale context).
  4824 
  4825 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4826 and type checking (Syntax.check_term etc.), with common combinations
  4827 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4828 which are considered legacy and await removal.
  4829 
  4830 * Pure/Syntax: generic interfaces for type unchecking
  4831 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4832 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4833 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4834 available for convenience, but refer to the very same operations using
  4835 a mere theory instead of a full context.
  4836 
  4837 * Isar: simplified treatment of user-level errors, using exception
  4838 ERROR of string uniformly.  Function error now merely raises ERROR,
  4839 without any side effect on output channels.  The Isar toplevel takes
  4840 care of proper display of ERROR exceptions.  ML code may use plain
  4841 handle/can/try; cat_error may be used to concatenate errors like this:
  4842 
  4843   ... handle ERROR msg => cat_error msg "..."
  4844 
  4845 Toplevel ML code (run directly or through the Isar toplevel) may be
  4846 embedded into the Isar toplevel with exception display/debug like
  4847 this:
  4848 
  4849   Isar.toplevel (fn () => ...)
  4850 
  4851 INCOMPATIBILITY, removed special transform_error facilities, removed
  4852 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4853 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4854 -- use plain ERROR instead.
  4855 
  4856 * Isar: theory setup now has type (theory -> theory), instead of a
  4857 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4858 
  4859 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4860 ProofContext.debug/verbose flags.
  4861 
  4862 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4863 theory before entering a proof state.  Transactions now always see a
  4864 quasi-functional intermediate checkpoint, both in interactive and
  4865 batch mode.
  4866 
  4867 * Isar: simplified interfaces for outer syntax.  Renamed
  4868 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4869 OuterSyntax.add_parsers -- this functionality is now included in
  4870 OuterSyntax.command etc.  INCOMPATIBILITY.
  4871 
  4872 * Simplifier: the simpset of a running simplification process now
  4873 contains a proof context (cf. Simplifier.the_context), which is the
  4874 very context that the initial simpset has been retrieved from (by
  4875 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4876 (solver, looper etc.) may depend on arbitrary proof data.
  4877 
  4878 * Simplifier.inherit_context inherits the proof context (plus the
  4879 local bounds) of the current simplification process; any simproc
  4880 etc. that calls the Simplifier recursively should do this!  Removed
  4881 former Simplifier.inherit_bounds, which is already included here --
  4882 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4883 specify an explicit context using Simplifier.context/theory_context.
  4884 
  4885 * Simplifier/Classical Reasoner: more abstract interfaces
  4886 change_simpset/claset for modifying the simpset/claset reference of a
  4887 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4888 INCOMPATIBILITY.
  4889 
  4890 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4891 "Trueprop" etc.
  4892 
  4893 
  4894 *** System ***
  4895 
  4896 * settings: the default heap location within ISABELLE_HOME_USER now
  4897 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4898 Isabelle installations.
  4899 
  4900 * isabelle-process: option -S (secure mode) disables some critical
  4901 operations, notably runtime compilation and evaluation of ML source
  4902 code.
  4903 
  4904 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4905 
  4906 * Support for parallel execution, using native multicore support of
  4907 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4908 independent theories, according to the given theory header
  4909 specifications. The maximum number of worker threads is specified via
  4910 usedir option -M or the "max-threads" setting in Proof General. A
  4911 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4912 to 6 on a 8-core machine.  User-code needs to observe certain
  4913 guidelines for thread-safe programming, see appendix A in the Isar
  4914 Implementation manual.
  4915 
  4916 
  4917 
  4918 New in Isabelle2005 (October 2005)
  4919 ----------------------------------
  4920 
  4921 *** General ***
  4922 
  4923 * Theory headers: the new header syntax for Isar theories is
  4924 
  4925   theory <name>
  4926   imports <theory1> ... <theoryN>
  4927   uses <file1> ... <fileM>
  4928   begin
  4929 
  4930 where the 'uses' part is optional.  The previous syntax
  4931 
  4932   theory <name> = <theory1> + ... + <theoryN>:
  4933 
  4934 will disappear in the next release.  Use isatool fixheaders to convert
  4935 existing theory files.  Note that there is no change in ancient
  4936 non-Isar theories now, but these will disappear soon.
  4937 
  4938 * Theory loader: parent theories can now also be referred to via
  4939 relative and absolute paths.
  4940 
  4941 * Command 'find_theorems' searches for a list of criteria instead of a
  4942 list of constants. Known criteria are: intro, elim, dest, name:string,
  4943 simp:term, and any term. Criteria can be preceded by '-' to select
  4944 theorems that do not match. Intro, elim, dest select theorems that
  4945 match the current goal, name:s selects theorems whose fully qualified
  4946 name contain s, and simp:term selects all simplification rules whose
  4947 lhs match term.  Any other term is interpreted as pattern and selects
  4948 all theorems matching the pattern. Available in ProofGeneral under
  4949 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4950 
  4951   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4952 
  4953 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4954 matching the current goal as introduction rule and not having "HOL."
  4955 in their name (i.e. not being defined in theory HOL).
  4956 
  4957 * Command 'thms_containing' has been discontinued in favour of
  4958 'find_theorems'; INCOMPATIBILITY.
  4959 
  4960 * Communication with Proof General is now 8bit clean, which means that
  4961 Unicode text in UTF-8 encoding may be used within theory texts (both
  4962 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4963 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4964 
  4965   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4966   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4967 
  4968 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4969 Classical Reasoner.  Typical big applications run around 2 times
  4970 faster.
  4971 
  4972 
  4973 *** Document preparation ***
  4974 
  4975 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4976 of raw sources.  Only those symbols that do not require additional
  4977 LaTeX packages (depending on comments in isabellesym.sty) are
  4978 displayed properly, everything else is left verbatim.  isatool display
  4979 and isatool print are used as front ends (these are subject to the
  4980 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4981 
  4982 * Command tags control specific markup of certain regions of text,
  4983 notably folding and hiding.  Predefined tags include "theory" (for
  4984 theory begin and end), "proof" for proof commands, and "ML" for
  4985 commands involving ML code; the additional tags "visible" and
  4986 "invisible" are unused by default.  Users may give explicit tag
  4987 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4988 interpretation of tags is determined by the LaTeX job during document
  4989 preparation: see option -V of isatool usedir, or options -n and -t of
  4990 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4991 \isadroptag.
  4992 
  4993 Several document versions may be produced at the same time via isatool
  4994 usedir (the generated index.html will link all of them).  Typical
  4995 specifications include ''-V document=theory,proof,ML'' to present
  4996 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4997 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4998 these parts without any formal replacement text.  The Isabelle site
  4999 default settings produce ''document'' and ''outline'' versions as
  5000 specified above.
  5001 
  5002 * Several new antiquotations:
  5003 
  5004   @{term_type term} prints a term with its type annotated;
  5005 
  5006   @{typeof term} prints the type of a term;
  5007 
  5008   @{const const} is the same as @{term const}, but checks that the
  5009   argument is a known logical constant;
  5010 
  5011   @{term_style style term} and @{thm_style style thm} print a term or
  5012   theorem applying a "style" to it
  5013 
  5014   @{ML text}
  5015 
  5016 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  5017 definitions, equations, inequations etc., 'concl' printing only the
  5018 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  5019 to print the specified premise.  TermStyle.add_style provides an ML
  5020 interface for introducing further styles.  See also the "LaTeX Sugar"
  5021 document practical applications.  The ML antiquotation prints
  5022 type-checked ML expressions verbatim.
  5023 
  5024 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  5025 and 'text' support optional locale specification '(in loc)', which
  5026 specifies the default context for interpreting antiquotations.  For
  5027 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  5028 
  5029 * Option 'locale=NAME' of antiquotations specifies an alternative
  5030 context interpreting the subsequent argument.  For example: @{thm
  5031 [locale=lattice] inf_assoc}.
  5032 
  5033 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  5034 a proof context.
  5035 
  5036 * Proper output of antiquotations for theory commands involving a
  5037 proof context (such as 'locale' or 'theorem (in loc) ...').
  5038 
  5039 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  5040 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  5041 
  5042 * isatool usedir: new option -C (default true) controls whether option
  5043 -D should include a copy of the original document directory; -C false
  5044 prevents unwanted effects such as copying of administrative CVS data.
  5045 
  5046 
  5047 *** Pure ***
  5048 
  5049 * Considerably improved version of 'constdefs' command.  Now performs
  5050 automatic type-inference of declared constants; additional support for
  5051 local structure declarations (cf. locales and HOL records), see also
  5052 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  5053 sequential dependencies of definitions within a single 'constdefs'
  5054 section; moreover, the declared name needs to be an identifier.  If
  5055 all fails, consider to fall back on 'consts' and 'defs' separately.
  5056 
  5057 * Improved indexed syntax and implicit structures.  First of all,
  5058 indexed syntax provides a notational device for subscripted
  5059 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  5060 expressions.  Secondly, in a local context with structure
  5061 declarations, number indexes \<^sub>n or the empty index (default
  5062 number 1) refer to a certain fixed variable implicitly; option
  5063 show_structs controls printing of implicit structures.  Typical
  5064 applications of these concepts involve record types and locales.
  5065 
  5066 * New command 'no_syntax' removes grammar declarations (and
  5067 translations) resulting from the given syntax specification, which is
  5068 interpreted in the same manner as for the 'syntax' command.
  5069 
  5070 * 'Advanced' translation functions (parse_translation etc.) may depend
  5071 on the signature of the theory context being presently used for
  5072 parsing/printing, see also isar-ref manual.
  5073 
  5074 * Improved 'oracle' command provides a type-safe interface to turn an
  5075 ML expression of type theory -> T -> term into a primitive rule of
  5076 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  5077 is already included here); see also FOL/ex/IffExample.thy;
  5078 INCOMPATIBILITY.
  5079 
  5080 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  5081 before); "cI" is no longer bound, use "c.intro" instead.
  5082 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  5083 axclasses vs. locales.
  5084 
  5085 * Improved internal renaming of symbolic identifiers -- attach primes
  5086 instead of base 26 numbers.
  5087 
  5088 * New flag show_question_marks controls printing of leading question
  5089 marks in schematic variable names.
  5090 
  5091 * In schematic variable names, *any* symbol following \<^isub> or
  5092 \<^isup> is now treated as part of the base name.  For example, the
  5093 following works without printing of awkward ".0" indexes:
  5094 
  5095   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5096     by simp
  5097 
  5098 * Inner syntax includes (*(*nested*) comments*).
  5099 
  5100 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5101 annotations as "(00...)".
  5102 
  5103 * Clear separation of logical types and nonterminals, where the latter
  5104 may only occur in 'syntax' specifications or type abbreviations.
  5105 Before that distinction was only partially implemented via type class
  5106 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5107 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5108 exotic syntax specifications may require further adaption
  5109 (e.g. Cube/Cube.thy).
  5110 
  5111 * Removed obsolete type class "logic", use the top sort {} instead.
  5112 Note that non-logical types should be declared as 'nonterminals'
  5113 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5114 specifications.
  5115 
  5116 * Attributes 'induct' and 'cases': type or set names may now be
  5117 locally fixed variables as well.
  5118 
  5119 * Simplifier: can now control the depth to which conditional rewriting
  5120 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5121 Limit.
  5122 
  5123 * Simplifier: simplification procedures may now take the current
  5124 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5125 interface), which is very useful for calling the Simplifier
  5126 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5127 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5128 low-level mk_simproc no longer applies Logic.varify internally, to
  5129 allow for use in a context of fixed variables.
  5130 
  5131 * thin_tac now works even if the assumption being deleted contains !!
  5132 or ==>.  More generally, erule now works even if the major premise of
  5133 the elimination rule contains !! or ==>.
  5134 
  5135 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5136 
  5137 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5138 from Pure, which contains all common declarations already.  Both
  5139 theories are defined via plain Isabelle/Isar .thy files.
  5140 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5141 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5142 use isatool fixcpure to adapt your theory and ML sources.
  5143 
  5144 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5145 selections of theorems in named facts via index ranges.
  5146 
  5147 * 'print_theorems': in theory mode, really print the difference
  5148 wrt. the last state (works for interactive theory development only),
  5149 in proof mode print all local facts (cf. 'print_facts');
  5150 
  5151 * 'hide': option '(open)' hides only base names.
  5152 
  5153 * More efficient treatment of intermediate checkpoints in interactive
  5154 theory development.
  5155 
  5156 * Code generator is now invoked via code_module (incremental code
  5157 generation) and code_library (modular code generation, ML structures
  5158 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5159 must be quoted when used as identifiers.
  5160 
  5161 * New 'value' command for reading, evaluating and printing terms using
  5162 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5163 quoted when used as identifier.
  5164 
  5165 
  5166 *** Locales ***
  5167 
  5168 * New commands for the interpretation of locale expressions in
  5169 theories (1), locales (2) and proof contexts (3).  These generate
  5170 proof obligations from the expression specification.  After the
  5171 obligations have been discharged, theorems of the expression are added
  5172 to the theory, target locale or proof context.  The synopsis of the
  5173 commands is a follows:
  5174 
  5175   (1) interpretation expr inst
  5176   (2) interpretation target < expr
  5177   (3) interpret expr inst
  5178 
  5179 Interpretation in theories and proof contexts require a parameter
  5180 instantiation of terms from the current context.  This is applied to
  5181 specifications and theorems of the interpreted expression.
  5182 Interpretation in locales only permits parameter renaming through the
  5183 locale expression.  Interpretation is smart in that interpretations
  5184 that are active already do not occur in proof obligations, neither are
  5185 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5186 inspect active interpretations of a particular locale.  For details,
  5187 see the Isar Reference manual.  Examples can be found in
  5188 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5189 
  5190 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5191 'interpret' instead.
  5192 
  5193 * New context element 'constrains' for adding type constraints to
  5194 parameters.
  5195 
  5196 * Context expressions: renaming of parameters with syntax
  5197 redeclaration.
  5198 
  5199 * Locale declaration: 'includes' disallowed.
  5200 
  5201 * Proper static binding of attribute syntax -- i.e. types / terms /
  5202 facts mentioned as arguments are always those of the locale definition
  5203 context, independently of the context of later invocations.  Moreover,
  5204 locale operations (renaming and type / term instantiation) are applied
  5205 to attribute arguments as expected.
  5206 
  5207 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5208 actual attributes; rare situations may require Attrib.attribute to
  5209 embed those attributes into Attrib.src that lack concrete syntax.
  5210 Attribute implementations need to cooperate properly with the static
  5211 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5212 Attrib.XXX_thm etc. already do the right thing without further
  5213 intervention.  Only unusual applications -- such as "where" or "of"
  5214 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5215 on the context and the facts involved -- may have to assign parsed
  5216 values to argument tokens explicitly.
  5217 
  5218 * Changed parameter management in theorem generation for long goal
  5219 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5220 theorem statement in rare situations.
  5221 
  5222 * Locale inspection command 'print_locale' omits notes elements.  Use
  5223 'print_locale!' to have them included in the output.
  5224 
  5225 
  5226 *** Provers ***
  5227 
  5228 * Provers/hypsubst.ML: improved version of the subst method, for
  5229 single-step rewriting: it now works in bound variable contexts. New is
  5230 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5231 rewrite a different subterm than the original subst method, which is
  5232 still available as 'simplesubst'.
  5233 
  5234 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5235 and quasi orders.
  5236 
  5237 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5238 reflexive-transitive closure of relations.
  5239 
  5240 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5241 limit (previously hard-coded with a value of 20) user-definable.
  5242 
  5243 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5244 is peformed already.  Object-logics merely need to finish their
  5245 initial simpset configuration as before.  INCOMPATIBILITY.
  5246 
  5247 
  5248 *** HOL ***
  5249 
  5250 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5251 
  5252   syntax (epsilon)
  5253     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5254 
  5255 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5256 and x-symbol; use option '-m epsilon' to get it actually printed.
  5257 Moreover, the mathematically important symbolic identifier \<epsilon>
  5258 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5259 
  5260 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5261 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5262 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5263 support corresponding Isar calculations.
  5264 
  5265 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5266 instead of ":".
  5267 
  5268 * theory SetInterval: changed the syntax for open intervals:
  5269 
  5270   Old       New
  5271   {..n(}    {..<n}
  5272   {)n..}    {n<..}
  5273   {m..n(}   {m..<n}
  5274   {)m..n}   {m<..n}
  5275   {)m..n(}  {m<..<n}
  5276 
  5277 The old syntax is still supported but will disappear in the next
  5278 release.  For conversion use the following Emacs search and replace
  5279 patterns (these are not perfect but work quite well):
  5280 
  5281   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5282   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5283 
  5284 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5285 equalities in commutative rings; method 'algebra' provides a generic
  5286 interface.
  5287 
  5288 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5289 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5290 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5291 be a tuple pattern.
  5292 
  5293 Some new syntax forms are available:
  5294 
  5295   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5296   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5297   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5298   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5299 
  5300 The latter form "\<Sum>x < k. e" used to be based on a separate
  5301 function "Summation", which has been discontinued.
  5302 
  5303 * theory Finite_Set: in structured induction proofs, the insert case
  5304 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5305 (insert F x)'.
  5306 
  5307 * The 'refute' command has been extended to support a much larger
  5308 fragment of HOL, including axiomatic type classes, constdefs and
  5309 typedefs, inductive datatypes and recursion.
  5310 
  5311 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5312 Requires zChaff with proof generation to be installed.  See
  5313 HOL/ex/SAT_Examples.thy for examples.
  5314 
  5315 * Datatype induction via method 'induct' now preserves the name of the
  5316 induction variable. For example, when proving P(xs::'a list) by
  5317 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5318 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5319 in unstructured proof scripts.
  5320 
  5321 * Reworked implementation of records.  Improved scalability for
  5322 records with many fields, avoiding performance problems for type
  5323 inference. Records are no longer composed of nested field types, but
  5324 of nested extension types. Therefore the record type only grows linear
  5325 in the number of extensions and not in the number of fields.  The
  5326 top-level (users) view on records is preserved.  Potential
  5327 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5328 old record representation. The type generated for a record is called
  5329 <record_name>_ext_type.
  5330 
  5331 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5332 proofs triggered by a record definition or a simproc (if
  5333 quick_and_dirty is enabled).  Definitions of large records can take
  5334 quite long.
  5335 
  5336 New simproc record_upd_simproc for simplification of multiple record
  5337 updates enabled by default.  Moreover, trivial updates are also
  5338 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5339 occasionally, since simplification is more powerful by default.
  5340 
  5341 * typedef: proper support for polymorphic sets, which contain extra
  5342 type-variables in the term.
  5343 
  5344 * Simplifier: automatically reasons about transitivity chains
  5345 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5346 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5347 old proofs break occasionally as simplification may now solve more
  5348 goals than previously.
  5349 
  5350 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5351 present.  Works for all partial orders (class "order"), in particular
  5352 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5353 just like y <= x.
  5354 
  5355 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5356 bound variable or a constant then the let is unfolded.  Otherwise
  5357 first a is simplified to b, and then f b is simplified to g. If
  5358 possible we abstract b from g arriving at "let x = b in h x",
  5359 otherwise we unfold the let and arrive at g.  The simproc can be
  5360 enabled/disabled by the reference use_let_simproc.  Potential
  5361 INCOMPATIBILITY since simplification is more powerful by default.
  5362 
  5363 * Classical reasoning: the meson method now accepts theorems as arguments.
  5364 
  5365 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5366 jobs to provide advice on the provability of subgoals.
  5367 
  5368 * Theory OrderedGroup and Ring_and_Field: various additions and
  5369 improvements to faciliate calculations involving equalities and
  5370 inequalities.
  5371 
  5372 The following theorems have been eliminated or modified
  5373 (INCOMPATIBILITY):
  5374 
  5375   abs_eq             now named abs_of_nonneg
  5376   abs_of_ge_0        now named abs_of_nonneg
  5377   abs_minus_eq       now named abs_of_nonpos
  5378   imp_abs_id         now named abs_of_nonneg
  5379   imp_abs_neg_id     now named abs_of_nonpos
  5380   mult_pos           now named mult_pos_pos
  5381   mult_pos_le        now named mult_nonneg_nonneg
  5382   mult_pos_neg_le    now named mult_nonneg_nonpos
  5383   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5384   mult_neg           now named mult_neg_neg
  5385   mult_neg_le        now named mult_nonpos_nonpos
  5386 
  5387 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5388      
  5389      zero_le_square
  5390      not_square_less_zero 
  5391 
  5392   The following lemmas have been deleted from Real/RealPow:
  5393   
  5394      realpow_zero_zero
  5395      realpow_two
  5396      realpow_less
  5397      zero_le_power
  5398      realpow_two_le
  5399      abs_realpow_two
  5400      realpow_two_abs     
  5401 
  5402 * Theory Parity: added rules for simplifying exponents.
  5403 
  5404 * Theory List:
  5405 
  5406 The following theorems have been eliminated or modified
  5407 (INCOMPATIBILITY):
  5408 
  5409   list_all_Nil       now named list_all.simps(1)
  5410   list_all_Cons      now named list_all.simps(2)
  5411   list_all_conv      now named list_all_iff
  5412   set_mem_eq         now named mem_iff
  5413 
  5414 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5415 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5416 
  5417 
  5418 *** HOL-Complex ***
  5419 
  5420 * Theory RealDef: better support for embedding natural numbers and
  5421 integers in the reals.
  5422 
  5423 The following theorems have been eliminated or modified
  5424 (INCOMPATIBILITY):
  5425 
  5426   exp_ge_add_one_self  now requires no hypotheses
  5427   real_of_int_add      reversed direction of equality (use [symmetric])
  5428   real_of_int_minus    reversed direction of equality (use [symmetric])
  5429   real_of_int_diff     reversed direction of equality (use [symmetric])
  5430   real_of_int_mult     reversed direction of equality (use [symmetric])
  5431 
  5432 * Theory RComplete: expanded support for floor and ceiling functions.
  5433 
  5434 * Theory Ln is new, with properties of the natural logarithm
  5435 
  5436 * Hyperreal: There is a new type constructor "star" for making
  5437 nonstandard types.  The old type names are now type synonyms:
  5438 
  5439   hypreal = real star
  5440   hypnat = nat star
  5441   hcomplex = complex star
  5442 
  5443 * Hyperreal: Many groups of similarly-defined constants have been
  5444 replaced by polymorphic versions (INCOMPATIBILITY):
  5445 
  5446   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5447 
  5448   starset      <-- starsetNat, starsetC
  5449   *s*          <-- *sNat*, *sc*
  5450   starset_n    <-- starsetNat_n, starsetC_n
  5451   *sn*         <-- *sNatn*, *scn*
  5452   InternalSets <-- InternalNatSets, InternalCSets
  5453 
  5454   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5455   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5456   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5457   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5458   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5459 
  5460 * Hyperreal: Many type-specific theorems have been removed in favor of
  5461 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5462 
  5463   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5464   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5465   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5466   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5467   right_minus <-- hypreal_add_minus
  5468   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5469   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5470   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5471   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5472   mult_1_right <-- hcomplex_mult_one_right
  5473   mult_zero_left <-- hcomplex_mult_zero_left
  5474   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5475   right_distrib <-- hypnat_add_mult_distrib2
  5476   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5477   right_inverse <-- hypreal_mult_inverse
  5478   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5479   order_refl <-- {hypreal,hypnat}_le_refl
  5480   order_trans <-- {hypreal,hypnat}_le_trans
  5481   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5482   order_less_le <-- {hypreal,hypnat}_less_le
  5483   linorder_linear <-- {hypreal,hypnat}_le_linear
  5484   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5485   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5486   add_nonneg_nonneg <-- hypreal_le_add_order
  5487 
  5488 * Hyperreal: Separate theorems having to do with type-specific
  5489 versions of constants have been merged into theorems that apply to the
  5490 new polymorphic constants (INCOMPATIBILITY):
  5491 
  5492   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5493   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5494   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5495   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5496   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5497   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5498   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5499   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5500   STAR_diff <-- {STAR,STARC}_diff
  5501   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5502     STARC_hcomplex_of_complex}_image_subset
  5503   starset_n_Un <-- starset{Nat,C}_n_Un
  5504   starset_n_Int <-- starset{Nat,C}_n_Int
  5505   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5506   starset_n_diff <-- starset{Nat,C}_n_diff
  5507   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5508   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5509   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5510   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5511   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5512   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5513   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5514   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5515   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5516   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5517   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5518   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5519   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5520   starfun_diff <-- starfun{C,RC,CR}_diff
  5521   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5522   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5523   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5524   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5525   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5526   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5527   starfun_Id <-- starfunC_Id
  5528   starfun_approx <-- starfun{Nat,CR}_approx
  5529   starfun_capprox <-- starfun{C,RC}_capprox
  5530   starfun_abs <-- starfunNat_rabs
  5531   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5532   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5533   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5534   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5535   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5536   starfun_add_approx <-- starfunCR_add_approx
  5537   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5538   starfun_divide <-- starfun{C,CR,RC}_divide
  5539   starfun_n <-- starfun{Nat,C}_n
  5540   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5541   starfun_n_add <-- starfun{Nat,C}_n_add
  5542   starfun_n_add_minus <-- starfunNat_n_add_minus
  5543   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5544   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5545   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5546 
  5547   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5548   star_n_minus <-- {hypreal,hcomplex}_minus
  5549   star_n_diff <-- {hypreal,hcomplex}_diff
  5550   star_n_mult <-- {hypreal,hcomplex}_mult
  5551   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5552   star_n_le <-- {hypreal,hypnat}_le
  5553   star_n_less <-- {hypreal,hypnat}_less
  5554   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5555   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5556   star_n_abs <-- hypreal_hrabs
  5557   star_n_divide <-- hcomplex_divide
  5558 
  5559   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5560   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5561   star_of_diff <-- hypreal_of_real_diff
  5562   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5563   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5564   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5565   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5566   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5567   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5568   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5569   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5570   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5571   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5572   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5573   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5574   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5575   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5576   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5577   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5578   star_of_power <-- hypreal_of_real_power
  5579   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5580 
  5581 * Hyperreal: new method "transfer" that implements the transfer
  5582 principle of nonstandard analysis. With a subgoal that mentions
  5583 nonstandard types like "'a star", the command "apply transfer"
  5584 replaces it with an equivalent one that mentions only standard types.
  5585 To be successful, all free variables must have standard types; non-
  5586 standard variables must have explicit universal quantifiers.
  5587 
  5588 * Hyperreal: A theory of Taylor series.
  5589 
  5590 
  5591 *** HOLCF ***
  5592 
  5593 * Discontinued special version of 'constdefs' (which used to support
  5594 continuous functions) in favor of the general Pure one with full
  5595 type-inference.
  5596 
  5597 * New simplification procedure for solving continuity conditions; it
  5598 is much faster on terms with many nested lambda abstractions (cubic
  5599 instead of exponential time).
  5600 
  5601 * New syntax for domain package: selector names are now optional.
  5602 Parentheses should be omitted unless argument is lazy, for example:
  5603 
  5604   domain 'a stream = cons "'a" (lazy "'a stream")
  5605 
  5606 * New command 'fixrec' for defining recursive functions with pattern
  5607 matching; defining multiple functions with mutual recursion is also
  5608 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5609 sinr, or any data constructor defined by the domain package. The given
  5610 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5611 syntax and examples.
  5612 
  5613 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5614 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5615 but the proof obligation additionally includes an admissibility
  5616 requirement. The packages generate instances of class cpo or pcpo,
  5617 with continuity and strictness theorems for Rep and Abs.
  5618 
  5619 * HOLCF: Many theorems have been renamed according to a more standard naming
  5620 scheme (INCOMPATIBILITY):
  5621 
  5622   foo_inject:  "foo$x = foo$y ==> x = y"
  5623   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5624   foo_less:    "(foo$x << foo$y) = (x << y)"
  5625   foo_strict:  "foo$UU = UU"
  5626   foo_defined: "... ==> foo$x ~= UU"
  5627   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5628 
  5629 
  5630 *** ZF ***
  5631 
  5632 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5633 including the First Isomorphism Theorem (on quotienting by the kernel
  5634 of a homomorphism).
  5635 
  5636 * ZF/Simplifier: install second copy of type solver that actually
  5637 makes use of TC rules declared to Isar proof contexts (or locales);
  5638 the old version is still required for ML proof scripts.
  5639 
  5640 
  5641 *** Cube ***
  5642 
  5643 * Converted to Isar theory format; use locales instead of axiomatic
  5644 theories.
  5645 
  5646 
  5647 *** ML ***
  5648 
  5649 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5650 for ||>, ||>>, |>>,
  5651 
  5652 * Pure/library.ML no longer defines its own option datatype, but uses
  5653 that of the SML basis, which has constructors NONE and SOME instead of
  5654 None and Some, as well as exception Option.Option instead of OPTION.
  5655 The functions the, if_none, is_some, is_none have been adapted
  5656 accordingly, while Option.map replaces apsome.
  5657 
  5658 * Pure/library.ML: the exception LIST has been given up in favour of
  5659 the standard exceptions Empty and Subscript, as well as
  5660 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5661 superceded by the standard hd and tl functions etc.
  5662 
  5663 A number of basic list functions are no longer exported to the ML
  5664 toplevel, as they are variants of predefined functions.  The following
  5665 suggests how one can translate existing code:
  5666 
  5667     rev_append xs ys = List.revAppend (xs, ys)
  5668     nth_elem (i, xs) = List.nth (xs, i)
  5669     last_elem xs = List.last xs
  5670     flat xss = List.concat xss
  5671     seq fs = List.app fs
  5672     partition P xs = List.partition P xs
  5673     mapfilter f xs = List.mapPartial f xs
  5674 
  5675 * Pure/library.ML: several combinators for linear functional
  5676 transformations, notably reverse application and composition:
  5677 
  5678   x |> f                f #> g
  5679   (x, y) |-> f          f #-> g
  5680 
  5681 * Pure/library.ML: introduced/changed precedence of infix operators:
  5682 
  5683   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5684   infix 2 ?;
  5685   infix 3 o oo ooo oooo;
  5686   infix 4 ~~ upto downto;
  5687 
  5688 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5689 infix operators.
  5690 
  5691 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5692 fold_map support linear functional transformations and nesting.  For
  5693 example:
  5694 
  5695   fold f [x1, ..., xN] y =
  5696     y |> f x1 |> ... |> f xN
  5697 
  5698   (fold o fold) f [xs1, ..., xsN] y =
  5699     y |> fold f xs1 |> ... |> fold f xsN
  5700 
  5701   fold f [x1, ..., xN] =
  5702     f x1 #> ... #> f xN
  5703 
  5704   (fold o fold) f [xs1, ..., xsN] =
  5705     fold f xs1 #> ... #> fold f xsN
  5706 
  5707 * Pure/library.ML: the following selectors on type 'a option are
  5708 available:
  5709 
  5710   the:               'a option -> 'a  (*partial*)
  5711   these:             'a option -> 'a  where 'a = 'b list
  5712   the_default: 'a -> 'a option -> 'a
  5713   the_list:          'a option -> 'a list
  5714 
  5715 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5716 basic operations for association lists, following natural argument
  5717 order; moreover the explicit equality predicate passed here avoids
  5718 potentially expensive polymorphic runtime equality checks.
  5719 The old functions may be expressed as follows:
  5720 
  5721   assoc = uncurry (AList.lookup (op =))
  5722   assocs = these oo AList.lookup (op =)
  5723   overwrite = uncurry (AList.update (op =)) o swap
  5724 
  5725 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5726 
  5727   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5728   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5729 
  5730 replacing make_keylist and keyfilter (occassionally used)
  5731 Naive rewrites:
  5732 
  5733   make_keylist = AList.make
  5734   keyfilter = AList.find (op =)
  5735 
  5736 * eq_fst and eq_snd now take explicit equality parameter, thus
  5737   avoiding eqtypes. Naive rewrites:
  5738 
  5739     eq_fst = eq_fst (op =)
  5740     eq_snd = eq_snd (op =)
  5741 
  5742 * Removed deprecated apl and apr (rarely used).
  5743   Naive rewrites:
  5744 
  5745     apl (n, op) =>>= curry op n
  5746     apr (op, m) =>>= fn n => op (n, m)
  5747 
  5748 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5749 provides a reasonably efficient light-weight implementation of sets as
  5750 lists.
  5751 
  5752 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5753 few new operations; existing lookup and update are now curried to
  5754 follow natural argument order (for use with fold etc.);
  5755 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5756 
  5757 * Pure/General: output via the Isabelle channels of
  5758 writeln/warning/error etc. is now passed through Output.output, with a
  5759 hook for arbitrary transformations depending on the print_mode
  5760 (cf. Output.add_mode -- the first active mode that provides a output
  5761 function wins).  Already formatted output may be embedded into further
  5762 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5763 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5764 accommodate easy composition of diagnostic messages etc.  Programmers
  5765 rarely need to care about Output.output or Output.raw at all, with
  5766 some notable exceptions: Output.output is required when bypassing the
  5767 standard channels (writeln etc.), or in token translations to produce
  5768 properly formatted results; Output.raw is required when capturing
  5769 already output material that will eventually be presented to the user
  5770 a second time.  For the default print mode, both Output.output and
  5771 Output.raw have no effect.
  5772 
  5773 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5774 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5775 cumulative results are displayed at the end of a batch session.
  5776 
  5777 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5778 replaced by File.platform_path and File.shell_path (with appropriate
  5779 hooks).  This provides a clean interface for unusual systems where the
  5780 internal and external process view of file names are different.
  5781 
  5782 * Pure: more efficient orders for basic syntactic entities: added
  5783 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5784 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5785 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5786 orders now -- potential INCOMPATIBILITY for code that depends on a
  5787 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5788 Library.sort_strings on result).
  5789 
  5790 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5791 fold_types traverse types/terms from left to right, observing natural
  5792 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5793 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5794 
  5795 * Pure: name spaces have been refined, with significant changes of the
  5796 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5797 to extern(_table).  The plain name entry path is superceded by a
  5798 general 'naming' context, which also includes the 'policy' to produce
  5799 a fully qualified name and external accesses of a fully qualified
  5800 name; NameSpace.extend is superceded by context dependent
  5801 Sign.declare_name.  Several theory and proof context operations modify
  5802 the naming context.  Especially note Theory.restore_naming and
  5803 ProofContext.restore_naming to get back to a sane state; note that
  5804 Theory.add_path is no longer sufficient to recover from
  5805 Theory.absolute_path in particular.
  5806 
  5807 * Pure: new flags short_names (default false) and unique_names
  5808 (default true) for controlling output of qualified names.  If
  5809 short_names is set, names are printed unqualified.  If unique_names is
  5810 reset, the name prefix is reduced to the minimum required to achieve
  5811 the original result when interning again, even if there is an overlap
  5812 with earlier declarations.
  5813 
  5814 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5815 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5816 (useful for printing error messages).  INCOMPATIBILITY.
  5817 
  5818 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5819 Theory.theory are now identified, referring to the universal
  5820 Context.theory (see Pure/context.ML).  Actual signature and theory
  5821 content is managed as theory data.  The old code and interfaces were
  5822 spread over many files and structures; the new arrangement introduces
  5823 considerable INCOMPATIBILITY to gain more clarity:
  5824 
  5825   Context -- theory management operations (name, identity, inclusion,
  5826     parents, ancestors, merge, etc.), plus generic theory data;
  5827 
  5828   Sign -- logical signature and syntax operations (declaring consts,
  5829     types, etc.), plus certify/read for common entities;
  5830 
  5831   Theory -- logical theory operations (stating axioms, definitions,
  5832     oracles), plus a copy of logical signature operations (consts,
  5833     types, etc.); also a few basic management operations (Theory.copy,
  5834     Theory.merge, etc.)
  5835 
  5836 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5837 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5838 for convenience -- they merely return the theory.
  5839 
  5840 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5841 
  5842 * Pure: the Isar proof context type is already defined early in Pure
  5843 as Context.proof (note that ProofContext.context and Proof.context are
  5844 aliases, where the latter is the preferred name).  This enables other
  5845 Isabelle components to refer to that type even before Isar is present.
  5846 
  5847 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5848 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5849 any of these kinds.  For example, Sign.intern typeK is now
  5850 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5851 Theory.hide_types.  Also note that former
  5852 Theory.hide_classes/types/consts are now
  5853 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5854 internalize their arguments!  INCOMPATIBILITY.
  5855 
  5856 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5857 datatype thmref (with constructors Name and NameSelection) instead of
  5858 plain string -- INCOMPATIBILITY;
  5859 
  5860 * Pure: cases produced by proof methods specify options, where NONE
  5861 means to remove case bindings -- INCOMPATIBILITY in
  5862 (RAW_)METHOD_CASES.
  5863 
  5864 * Pure: the following operations retrieve axioms or theorems from a
  5865 theory node or theory hierarchy, respectively:
  5866 
  5867   Theory.axioms_of: theory -> (string * term) list
  5868   Theory.all_axioms_of: theory -> (string * term) list
  5869   PureThy.thms_of: theory -> (string * thm) list
  5870   PureThy.all_thms_of: theory -> (string * thm) list
  5871 
  5872 * Pure: print_tac now outputs the goal through the trace channel.
  5873 
  5874 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5875 Reference Toplevel.debug (default false) controls detailed printing
  5876 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5877 controls execution profiling -- set to 1 for time and 2 for space
  5878 (both increase the runtime).
  5879 
  5880 * Isar session: The initial use of ROOT.ML is now always timed,
  5881 i.e. the log will show the actual process times, in contrast to the
  5882 elapsed wall-clock time that the outer shell wrapper produces.
  5883 
  5884 * Simplifier: improved handling of bound variables (nameless
  5885 representation, avoid allocating new strings).  Simprocs that invoke
  5886 the Simplifier recursively should use Simplifier.inherit_bounds to
  5887 avoid local name clashes.  Failure to do so produces warnings
  5888 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5889 for further details.
  5890 
  5891 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5892 bindings for all theorems stored within a given theory; this may help
  5893 in porting non-Isar theories to Isar ones, while keeping ML proof
  5894 scripts for the time being.
  5895 
  5896 * ML operator HTML.with_charset specifies the charset begin used for
  5897 generated HTML files.  For example:
  5898 
  5899   HTML.with_charset "utf-8" use_thy "Hebrew";
  5900   HTML.with_charset "utf-8" use_thy "Chinese";
  5901 
  5902 
  5903 *** System ***
  5904 
  5905 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5906 isabelle, isatool etc.).
  5907 
  5908 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5909 isatool doc, isatool mkdir, display_drafts etc.).
  5910 
  5911 * isatool usedir: option -f allows specification of the ML file to be
  5912 used by Isabelle; default is ROOT.ML.
  5913 
  5914 * New isatool version outputs the version identifier of the Isabelle
  5915 distribution being used.
  5916 
  5917 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5918 (containing Boolean satisfiability problems) into Isabelle/HOL
  5919 theories.
  5920 
  5921 
  5922 
  5923 New in Isabelle2004 (April 2004)
  5924 --------------------------------
  5925 
  5926 *** General ***
  5927 
  5928 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5929   Replaces linorder.ML.
  5930 
  5931 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5932   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5933   (\<a>...\<z>), are now considered normal letters, and can therefore
  5934   be used anywhere where an ASCII letter (a...zA...Z) has until
  5935   now. COMPATIBILITY: This obviously changes the parsing of some
  5936   terms, especially where a symbol has been used as a binder, say
  5937   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5938   as an identifier.  Fix it by inserting a space around former
  5939   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5940   existing theory and ML files.
  5941 
  5942 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5943 
  5944 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5945   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5946   a normal (but invisible) letter. For multiple letter subscripts repeat
  5947   \<^isub> like this: x\<^isub>1\<^isub>2.
  5948 
  5949 * Pure: There are now sub-/superscripts that can span more than one
  5950   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5951   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5952   superscript. The new control characters are not identifier parts.
  5953 
  5954 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5955   content of "..." to the latex file instead of \isacntrl... . The "..."
  5956   may consist of any printable characters excluding the end bracket >.
  5957 
  5958 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5959   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5960   declare constants "final", which prevents their being given a definition
  5961   later.  It is useful for constants whose behaviour is fixed axiomatically
  5962   rather than definitionally, such as the meta-logic connectives.
  5963 
  5964 * Pure: 'instance' now handles general arities with general sorts
  5965   (i.e. intersections of classes),
  5966 
  5967 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5968   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5969   It can be changed to alter the colors/layout of generated pages.
  5970 
  5971 
  5972 *** Isar ***
  5973 
  5974 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5975   cut_tac, subgoal_tac and thin_tac:
  5976   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5977     locales are no longer forced to write Isar proof scripts.
  5978     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5979     emulations.
  5980   - INCOMPATIBILITY: names of variables to be instantiated may no
  5981     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5982     This is consistent with the instantiation attribute "where".
  5983 
  5984 * Attributes "where" and "of":
  5985   - Now take type variables of instantiated theorem into account when reading
  5986     the instantiation string.  This fixes a bug that caused instantiated
  5987     theorems to have too special types in some circumstances.
  5988   - "where" permits explicit instantiations of type variables.
  5989 
  5990 * Calculation commands "moreover" and "also" no longer interfere with
  5991   current facts ("this"), admitting arbitrary combinations with "then"
  5992   and derived forms.
  5993 
  5994 * Locales:
  5995   - Goal statements involving the context element "includes" no longer
  5996     generate theorems with internal delta predicates (those ending on
  5997     "_axioms") in the premise.
  5998     Resolve particular premise with <locale>.intro to obtain old form.
  5999   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  6000     specification and "includes" elements in goal statement.
  6001   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  6002     [intro?] and [elim?] (respectively) by default.
  6003   - Experimental command for instantiation of locales in proof contexts:
  6004         instantiate <label>[<attrs>]: <loc>
  6005     Instantiates locale <loc> and adds all its theorems to the current context
  6006     taking into account their attributes.  Label and attrs are optional
  6007     modifiers, like in theorem declarations.  If present, names of
  6008     instantiated theorems are qualified with <label>, and the attributes
  6009     <attrs> are applied after any attributes these theorems might have already.
  6010       If the locale has assumptions, a chained fact of the form
  6011     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  6012     are derived.  The command does not support old-style locales declared
  6013     with "locale (open)".
  6014       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  6015 
  6016 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  6017   (Isar) contexts.
  6018 
  6019 
  6020 *** HOL ***
  6021 
  6022 * Proof import: new image HOL4 contains the imported library from
  6023   the HOL4 system with about 2500 theorems. It is imported by
  6024   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  6025   can be used like any other Isabelle image.  See
  6026   HOL/Import/HOL/README for more information.
  6027 
  6028 * Simplifier:
  6029   - Much improved handling of linear and partial orders.
  6030     Reasoners for linear and partial orders are set up for type classes
  6031     "linorder" and "order" respectively, and are added to the default simpset
  6032     as solvers.  This means that the simplifier can build transitivity chains
  6033     to solve goals from the assumptions.
  6034   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  6035     of blast or auto after simplification become unnecessary because the goal
  6036     is solved by simplification already.
  6037 
  6038 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  6039     all proved in axiomatic type classes for semirings, rings and fields.
  6040 
  6041 * Numerics:
  6042   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  6043     now formalized using the Ring_and_Field theory mentioned above.
  6044   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  6045     than before, because now they are set up once in a generic manner.
  6046   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  6047     Look for the general versions in Ring_and_Field (and Power if they concern
  6048     exponentiation).
  6049 
  6050 * Type "rat" of the rational numbers is now available in HOL-Complex.
  6051 
  6052 * Records:
  6053   - Record types are now by default printed with their type abbreviation
  6054     instead of the list of all field types. This can be configured via
  6055     the reference "print_record_type_abbr".
  6056   - Simproc "record_upd_simproc" for simplification of multiple updates added
  6057     (not enabled by default).
  6058   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  6059     EX x. x = sel r to True (not enabled by default).
  6060   - Tactic "record_split_simp_tac" to split and simplify records added.
  6061 
  6062 * 'specification' command added, allowing for definition by
  6063   specification.  There is also an 'ax_specification' command that
  6064   introduces the new constants axiomatically.
  6065 
  6066 * arith(_tac) is now able to generate counterexamples for reals as well.
  6067 
  6068 * HOL-Algebra: new locale "ring" for non-commutative rings.
  6069 
  6070 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  6071   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  6072 
  6073 * HOL-Matrix: a first theory for matrices in HOL with an application of
  6074   matrix theory to linear programming.
  6075 
  6076 * Unions and Intersections:
  6077   The latex output syntax of UN and INT has been changed
  6078   from "\Union x \in A. B" to "\Union_{x \in A} B"
  6079   i.e. the index formulae has become a subscript.
  6080   Similarly for "\Union x. B", and for \Inter instead of \Union.
  6081 
  6082 * Unions and Intersections over Intervals:
  6083   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  6084   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  6085   like in normal math, and corresponding versions for < and for intersection.
  6086 
  6087 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  6088   lexicographic dictonary ordering has been added as "lexord".
  6089 
  6090 * ML: the legacy theory structures Int and List have been removed. They had
  6091   conflicted with ML Basis Library structures having the same names.
  6092 
  6093 * 'refute' command added to search for (finite) countermodels.  Only works
  6094   for a fragment of HOL.  The installation of an external SAT solver is
  6095   highly recommended.  See "HOL/Refute.thy" for details.
  6096 
  6097 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6098   formulae under an assignment of free variables to random values.
  6099   In contrast to 'refute', it can deal with inductive datatypes,
  6100   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6101   for examples.
  6102 
  6103 
  6104 *** HOLCF ***
  6105 
  6106 * Streams now come with concatenation and are part of the HOLCF image
  6107 
  6108 
  6109 
  6110 New in Isabelle2003 (May 2003)
  6111 ------------------------------
  6112 
  6113 *** General ***
  6114 
  6115 * Provers/simplifier:
  6116 
  6117   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6118     Assumptions are now subject to complete mutual simplification,
  6119     not just from left to right. The simplifier now preserves
  6120     the order of assumptions.
  6121 
  6122     Potential INCOMPATIBILITY:
  6123 
  6124     -- simp sometimes diverges where the old version did
  6125        not, e.g. invoking simp on the goal
  6126 
  6127         [| P (f x); y = x; f x = f y |] ==> Q
  6128 
  6129        now gives rise to the infinite reduction sequence
  6130 
  6131         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6132 
  6133        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6134        kind of problem.
  6135 
  6136     -- Tactics combining classical reasoner and simplification (such as auto)
  6137        are also affected by this change, because many of them rely on
  6138        simp. They may sometimes diverge as well or yield a different numbers
  6139        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6140        in case of problems. Sometimes subsequent calls to the classical
  6141        reasoner will fail because a preceeding call to the simplifier too
  6142        eagerly simplified the goal, e.g. deleted redundant premises.
  6143 
  6144   - The simplifier trace now shows the names of the applied rewrite rules
  6145 
  6146   - You can limit the number of recursive invocations of the simplifier
  6147     during conditional rewriting (where the simplifie tries to solve the
  6148     conditions before applying the rewrite rule):
  6149     ML "simp_depth_limit := n"
  6150     where n is an integer. Thus you can force termination where previously
  6151     the simplifier would diverge.
  6152 
  6153   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6154 
  6155   - No longer aborts on failed congruence proof.  Instead, the
  6156     congruence is ignored.
  6157 
  6158 * Pure: New generic framework for extracting programs from constructive
  6159   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6160   as HOL/Extraction for some case studies.
  6161 
  6162 * Pure: The main goal of the proof state is no longer shown by default, only
  6163 the subgoals. This behaviour is controlled by a new flag.
  6164    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6165 (ML: Proof.show_main_goal).
  6166 
  6167 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6168 rules whose conclusion matches subgoal 1:
  6169       PG menu: Isabelle/Isar -> Show me -> matching rules
  6170 The rules are ordered by how closely they match the subgoal.
  6171 In particular, rules that solve a subgoal outright are displayed first
  6172 (or rather last, the way they are printed).
  6173 (ML: ProofGeneral.print_intros())
  6174 
  6175 * Pure: New flag trace_unify_fail causes unification to print
  6176 diagnostic information (PG: in trace buffer) when it fails. This is
  6177 useful for figuring out why single step proofs like rule, erule or
  6178 assumption failed.
  6179 
  6180 * Pure: Locale specifications now produce predicate definitions
  6181 according to the body of text (covering assumptions modulo local
  6182 definitions); predicate "loc_axioms" covers newly introduced text,
  6183 while "loc" is cumulative wrt. all included locale expressions; the
  6184 latter view is presented only on export into the global theory
  6185 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6186 on the old view without predicates;
  6187 
  6188 * Pure: predefined locales "var" and "struct" are useful for sharing
  6189 parameters (as in CASL, for example); just specify something like
  6190 ``var x + var y + struct M'' as import;
  6191 
  6192 * Pure: improved thms_containing: proper indexing of facts instead of
  6193 raw theorems; check validity of results wrt. current name space;
  6194 include local facts of proof configuration (also covers active
  6195 locales), cover fixed variables in index; may use "_" in term
  6196 specification; an optional limit for the number of printed facts may
  6197 be given (the default is 40);
  6198 
  6199 * Pure: disallow duplicate fact bindings within new-style theory files
  6200 (batch-mode only);
  6201 
  6202 * Provers: improved induct method: assumptions introduced by case
  6203 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6204 the goal statement); "foo" still refers to all facts collectively;
  6205 
  6206 * Provers: the function blast.overloaded has been removed: all constants
  6207 are regarded as potentially overloaded, which improves robustness in exchange
  6208 for slight decrease in efficiency;
  6209 
  6210 * Provers/linorder: New generic prover for transitivity reasoning over
  6211 linear orders.  Note: this prover is not efficient!
  6212 
  6213 * Isar: preview of problems to finish 'show' now produce an error
  6214 rather than just a warning (in interactive mode);
  6215 
  6216 
  6217 *** HOL ***
  6218 
  6219 * arith(_tac)
  6220 
  6221  - Produces a counter example if it cannot prove a goal.
  6222    Note that the counter example may be spurious if the goal is not a formula
  6223    of quantifier-free linear arithmetic.
  6224    In ProofGeneral the counter example appears in the trace buffer.
  6225 
  6226  - Knows about div k and mod k where k is a numeral of type nat or int.
  6227 
  6228  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6229    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6230    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6231 
  6232 * simp's arithmetic capabilities have been enhanced a bit: it now
  6233 takes ~= in premises into account (by performing a case split);
<