NEWS
author huffman
Sun Aug 28 09:20:12 2011 -0700 (2011-08-28)
changeset 44568 e6f291cb5810
parent 44538 8037d25afa89
child 44647 e4de7750cdeb
permissions -rw-r--r--
discontinue many legacy theorems about LIM and LIMSEQ, in favor of tendsto theorems
     1 Isabelle NEWS -- history user-relevant changes
     2 ==============================================
     3 
     4 New in this Isabelle version
     5 ----------------------------
     6 
     7 *** General ***
     8 
     9 * Theory loader: source files are identified by content via SHA1
    10 digests.  Discontinued former path/modtime identification and optional
    11 ISABELLE_FILE_IDENT plugin scripts.
    12 
    13 * Parallelization of nested Isar proofs is subject to
    14 Goal.parallel_proofs_threshold (default 100).  See also isabelle
    15 usedir option -Q.
    16 
    17 * Discontinued support for Poly/ML 5.2, which was the last version
    18 without proper multithreading and TimeLimit implementation.
    19 
    20 * Discontinued old lib/scripts/polyml-platform, which has been
    21 obsolete since Isabelle2009-2.
    22 
    23 * Theory loader: source files are exclusively located via the master
    24 directory of each theory node (where the .thy file itself resides).
    25 The global load path (such as src/HOL/Library) has been discontinued.
    26 Note that the path element ~~ may be used to reference theories in the
    27 Isabelle home folder -- for instance, "~~/src/HOL/Library/FuncSet".
    28 INCOMPATIBILITY.
    29 
    30 * Various optional external tools are referenced more robustly and
    31 uniformly by explicit Isabelle settings as follows:
    32 
    33   ISABELLE_CSDP   (formerly CSDP_EXE)
    34   ISABELLE_GHC    (formerly EXEC_GHC or GHC_PATH)
    35   ISABELLE_OCAML  (formerly EXEC_OCAML)
    36   ISABELLE_SWIPL  (formerly EXEC_SWIPL)
    37   ISABELLE_YAP    (formerly EXEC_YAP)
    38 
    39 Note that automated detection from the file-system or search path has
    40 been discontinued.  INCOMPATIBILITY.
    41 
    42 * Name space: former unsynchronized references are now proper
    43 configuration options, with more conventional names:
    44 
    45   long_names   ~> names_long
    46   short_names  ~> names_short
    47   unique_names ~> names_unique
    48 
    49 Minor INCOMPATIBILITY, need to declare options in context like this:
    50 
    51   declare [[names_unique = false]]
    52 
    53 * Literal facts `prop` may contain dummy patterns, e.g. `_ = _`.  Note
    54 that the result needs to be unique, which means fact specifications
    55 may have to be refined after enriching a proof context.
    56 
    57 * Isabelle/Isar reference manual provides more formal references in
    58 syntax diagrams.
    59 
    60 * Attribute case_names has been refined: the assumptions in each case can
    61 be named now by following the case name with [name1 name2 ...].
    62 
    63 
    64 *** HOL ***
    65 
    66 * Classes bot and top require underlying partial order rather than preorder:
    67 uniqueness of bot and top is guaranteed.  INCOMPATIBILITY.
    68 
    69 * Class complete_lattice: generalized a couple of lemmas from sets;
    70 generalized theorems INF_cong and SUP_cong.  New type classes for complete
    71 boolean algebras and complete linear orders.  Lemmas Inf_less_iff,
    72 less_Sup_iff, INF_less_iff, less_SUP_iff now reside in class complete_linorder.
    73 Changed proposition of lemmas Inf_bool_def, Sup_bool_def, Inf_fun_def, Sup_fun_def,
    74 Inf_apply, Sup_apply.
    75 Redundant lemmas Inf_singleton, Sup_singleton, Inf_binary, Sup_binary,
    76 INF_eq, SUP_eq, INF_UNIV_range, SUP_UNIV_range, Int_eq_Inter,
    77 INTER_eq_Inter_image, Inter_def, INT_eq, Un_eq_Union, UNION_eq_Union_image,
    78 Union_def, UN_singleton, UN_eq have been discarded.
    79 More consistent and less misunderstandable names:
    80   INFI_def ~> INF_def
    81   SUPR_def ~> SUP_def
    82   INF_leI ~> INF_lower
    83   INF_leI2 ~> INF_lower2
    84   le_INFI ~> INF_greatest
    85   le_SUPI ~> SUP_upper
    86   le_SUPI2 ~> SUP_upper2
    87   SUP_leI ~> SUP_least
    88   INFI_bool_eq ~> INF_bool_eq
    89   SUPR_bool_eq ~> SUP_bool_eq
    90   INFI_apply ~> INF_apply
    91   SUPR_apply ~> SUP_apply
    92   INTER_def ~> INTER_eq
    93   UNION_def ~> UNION_eq
    94 
    95 INCOMPATIBILITY.
    96 
    97 * Theorem collections ball_simps and bex_simps do not contain theorems referring
    98 to UNION any longer;  these have been moved to collection UN_ball_bex_simps.
    99 INCOMPATIBILITY.
   100 
   101 * Archimedean_Field.thy:
   102     floor now is defined as parameter of a separate type class floor_ceiling.
   103  
   104 * Finite_Set.thy: more coherent development of fold_set locales:
   105 
   106     locale fun_left_comm ~> locale comp_fun_commute
   107     locale fun_left_comm_idem ~> locale comp_fun_idem
   108     
   109 Both use point-free characterisation; interpretation proofs may need adjustment.
   110 INCOMPATIBILITY.
   111 
   112 * Code generation:
   113   - theory Library/Code_Char_ord provides native ordering of characters
   114     in the target language.
   115   - commands code_module and code_library are legacy, use export_code instead. 
   116   - method evaluation is legacy, use method eval instead.
   117   - legacy evaluator "SML" is deactivated by default. To activate it, add the following
   118     line in your theory:
   119       setup {* Value.add_evaluator ("SML", Codegen.eval_term) *}
   120  
   121 * Declare ext [intro] by default.  Rare INCOMPATIBILITY.
   122 
   123 * Nitpick:
   124   - Added "need" and "total_consts" options.
   125   - Reintroduced "show_skolems" option by popular demand.
   126   - Renamed attribute: nitpick_def ~> nitpick_unfold.
   127     INCOMPATIBILITY.
   128 
   129 * Sledgehammer:
   130   - sledgehammer available_provers ~> sledgehammer supported_provers.
   131     INCOMPATIBILITY.
   132   - Added support for SNARK and ToFoF-E on SystemOnTPTP and for simply typed
   133     TPTP problems (TFF).
   134   - Added "preplay_timeout", "slicing", "type_enc", "sound", "max_mono_iters",
   135     and "max_new_mono_instances" options.
   136   - Removed "explicit_apply" and "full_types" options as well as "Full Types"
   137     Proof General menu item. INCOMPATIBILITY.
   138 
   139 * Metis:
   140   - Removed "metisF" -- use "metis" instead. INCOMPATIBILITY.
   141   - Obsoleted "metisFT" -- use "metis (full_types)" instead. INCOMPATIBILITY.
   142 
   143 * "try":
   144   - Renamed "try_methods" and added "simp:", "intro:", "dest:", and "elim:"
   145     options. INCOMPATIBILITY.
   146   - Introduced "try" that not only runs "try_methods" but also "solve_direct",
   147     "sledgehammer", "quickcheck", and "nitpick".
   148 
   149 * Quickcheck:
   150   - Added "eval" option to evaluate terms for the found counterexample
   151     (currently only supported by the default (exhaustive) tester)
   152   - Added post-processing of terms to obtain readable counterexamples
   153     (currently only supported by the default (exhaustive) tester)
   154   - New counterexample generator quickcheck[narrowing] enables
   155     narrowing-based testing.
   156     It requires that the Glasgow Haskell compiler is installed and
   157     its location is known to Isabelle with the environment variable
   158     ISABELLE_GHC.
   159   - Removed quickcheck tester "SML" based on the SML code generator
   160     from HOL-Library
   161 
   162 * Function package: discontinued option "tailrec".
   163 INCOMPATIBILITY. Use partial_function instead.
   164 
   165 * HOL-Probability:
   166   - Caratheodory's extension lemma is now proved for ring_of_sets.
   167   - Infinite products of probability measures are now available.
   168   - Use extended reals instead of positive extended reals.
   169     INCOMPATIBILITY.
   170 
   171 * Old recdef package has been moved to Library/Old_Recdef.thy, where it
   172 must be loaded explicitly.  INCOMPATIBILITY.
   173 
   174 * Well-founded recursion combinator "wfrec" has been moved to
   175 Library/Wfrec.thy. INCOMPATIBILITY.
   176 
   177 * Theory Library/Nat_Infinity has been renamed to Library/Extended_Nat.
   178 The names of the following types and constants have changed:
   179   inat (type) ~> enat
   180   Fin         ~> enat
   181   Infty       ~> infinity (overloaded)
   182   iSuc        ~> eSuc
   183   the_Fin     ~> the_enat
   184 Every theorem name containing "inat", "Fin", "Infty", or "iSuc" has
   185 been renamed accordingly.
   186 
   187 * Limits.thy: Type "'a net" has been renamed to "'a filter", in
   188 accordance with standard mathematical terminology. INCOMPATIBILITY.
   189 
   190 * Session Multivariate_Analysis: Type "('a, 'b) cart" has been renamed
   191 to "('a, 'b) vec" (the syntax "'a ^ 'b" remains unaffected). Constants
   192 "Cart_nth" and "Cart_lambda" have been respectively renamed to
   193 "vec_nth" and "vec_lambda"; theorems mentioning those names have
   194 changed to match. Definition theorems for overloaded constants now use
   195 the standard "foo_vec_def" naming scheme. A few other theorems have
   196 been renamed as follows (INCOMPATIBILITY):
   197 
   198   Cart_eq          ~> vec_eq_iff
   199   dist_nth_le_cart ~> dist_vec_nth_le
   200   tendsto_vector   ~> vec_tendstoI
   201   Cauchy_vector    ~> vec_CauchyI
   202 
   203 * Session Multivariate_Analysis: Several duplicate theorems have been
   204 removed, and other theorems have been renamed. INCOMPATIBILITY.
   205 
   206   eventually_conjI ~> eventually_conj
   207   eventually_and ~> eventually_conj_iff
   208   eventually_false ~> eventually_False
   209   setsum_norm ~> norm_setsum
   210   Lim_ident_at ~> LIM_ident
   211   Lim_const ~> tendsto_const
   212   Lim_cmul ~> tendsto_scaleR [OF tendsto_const]
   213   Lim_neg ~> tendsto_minus
   214   Lim_add ~> tendsto_add
   215   Lim_sub ~> tendsto_diff
   216   Lim_mul ~> tendsto_scaleR
   217   Lim_vmul ~> tendsto_scaleR [OF _ tendsto_const]
   218   Lim_null_norm ~> tendsto_norm_zero_iff [symmetric]
   219   Lim_linear ~> bounded_linear.tendsto
   220   Lim_component ~> tendsto_euclidean_component
   221   Lim_component_cart ~> tendsto_vec_nth
   222   Lim_inner ~> tendsto_inner [OF tendsto_const]
   223   dot_lsum ~> inner_setsum_left
   224   dot_rsum ~> inner_setsum_right
   225   continuous_on_neg ~> continuous_on_minus
   226   continuous_on_sub ~> continuous_on_diff
   227   continuous_on_cmul ~> continuous_on_scaleR [OF continuous_on_const]
   228   continuous_on_vmul ~> continuous_on_scaleR [OF _ continuous_on_const]
   229   continuous_on_mul ~> continuous_on_scaleR
   230   continuous_on_mul_real ~> continuous_on_mult
   231   continuous_on_inner ~> continuous_on_inner [OF continuous_on_const]
   232   subset_interior ~> interior_mono
   233   subset_closure ~> closure_mono
   234   closure_univ ~> closure_UNIV
   235 
   236 * Complex_Main: The locale interpretations for the bounded_linear and
   237 bounded_bilinear locales have been removed, in order to reduce the
   238 number of duplicate lemmas. Users must use the original names for
   239 distributivity theorems, potential INCOMPATIBILITY.
   240 
   241   divide.add ~> add_divide_distrib
   242   divide.diff ~> diff_divide_distrib
   243   divide.setsum ~> setsum_divide_distrib
   244   mult.add_right ~> right_distrib
   245   mult.diff_right ~> right_diff_distrib
   246   mult_right.setsum ~> setsum_right_distrib
   247   mult_left.diff ~> left_diff_distrib
   248 
   249 * Complex_Main: Several redundant theorems have been removed or
   250 replaced by more general versions. INCOMPATIBILITY.
   251 
   252   real_0_le_divide_iff ~> zero_le_divide_iff
   253   realpow_two_disj ~> power2_eq_iff
   254   real_squared_diff_one_factored ~> square_diff_one_factored
   255   realpow_two_diff ~> square_diff_square_factored
   256   exp_ln_eq ~> ln_unique
   257   lemma_DERIV_subst ~> DERIV_cong
   258   LIMSEQ_Zfun_iff ~> tendsto_Zfun_iff
   259   LIMSEQ_const ~> tendsto_const
   260   LIMSEQ_norm ~> tendsto_norm
   261   LIMSEQ_add ~> tendsto_add
   262   LIMSEQ_minus ~> tendsto_minus
   263   LIMSEQ_minus_cancel ~> tendsto_minus_cancel
   264   LIMSEQ_diff ~> tendsto_diff
   265   bounded_linear.LIMSEQ ~> bounded_linear.tendsto
   266   bounded_bilinear.LIMSEQ ~> bounded_bilinear.tendsto
   267   LIMSEQ_mult ~> tendsto_mult
   268   LIMSEQ_inverse ~> tendsto_inverse
   269   LIMSEQ_divide ~> tendsto_divide
   270   LIMSEQ_pow ~> tendsto_power
   271   LIMSEQ_setsum ~> tendsto_setsum
   272   LIMSEQ_setprod ~> tendsto_setprod
   273   LIMSEQ_norm_zero ~> tendsto_norm_zero_iff
   274   LIMSEQ_rabs_zero ~> tendsto_rabs_zero_iff
   275   LIMSEQ_imp_rabs ~> tendsto_rabs
   276   LIM_ident ~> tendsto_ident_at
   277   LIM_const ~> tendsto_const
   278   LIM_add ~> tendsto_add
   279   LIM_add_zero ~> tendsto_add_zero
   280   LIM_minus ~> tendsto_minus
   281   LIM_diff ~> tendsto_diff
   282   LIM_norm ~> tendsto_norm
   283   LIM_norm_zero ~> tendsto_norm_zero
   284   LIM_norm_zero_cancel ~> tendsto_norm_zero_cancel
   285   LIM_norm_zero_iff ~> tendsto_norm_zero_iff
   286   LIM_rabs ~> tendsto_rabs
   287   LIM_rabs_zero ~> tendsto_rabs_zero
   288   LIM_rabs_zero_cancel ~> tendsto_rabs_zero_cancel
   289   LIM_rabs_zero_iff ~> tendsto_rabs_zero_iff
   290   LIM_compose ~> tendsto_compose
   291   LIM_mult ~> tendsto_mult
   292   LIM_scaleR ~> tendsto_scaleR
   293   LIM_of_real ~> tendsto_of_real
   294   LIM_power ~> tendsto_power
   295   LIM_inverse ~> tendsto_inverse
   296   LIM_sgn ~> tendsto_sgn
   297   isCont_LIM_compose ~> isCont_tendsto_compose
   298   bounded_linear.LIM ~> bounded_linear.tendsto
   299   bounded_linear.LIM_zero ~> bounded_linear.tendsto_zero
   300   bounded_bilinear.LIM ~> bounded_bilinear.tendsto
   301   bounded_bilinear.LIM_prod_zero ~> bounded_bilinear.tendsto_zero
   302   bounded_bilinear.LIM_left_zero ~> bounded_bilinear.tendsto_left_zero
   303   bounded_bilinear.LIM_right_zero ~> bounded_bilinear.tendsto_right_zero
   304   LIM_inverse_fun ~> tendsto_inverse [OF tendsto_ident_at]
   305 
   306 
   307 *** Document preparation ***
   308 
   309 * Discontinued special treatment of hard tabulators, which are better
   310 avoided in the first place.  Implicit tab-width is 1.
   311 
   312 * Antiquotation @{rail} layouts railroad syntax diagrams, see also
   313 isar-ref manual.
   314 
   315 * Antiquotation @{value} evaluates the given term and presents its result.
   316 
   317 * Localized \isabellestyle switch can be used within blocks or groups
   318 like this:
   319 
   320   \isabellestyle{it}  %preferred default
   321   {\isabellestylett @{text "typewriter stuff"}}
   322 
   323 * New term style "isub" as ad-hoc conversion of variables x1, y23 into
   324 subscripted form x\<^isub>1, y\<^isub>2\<^isub>3.
   325 
   326 * Predefined LaTeX macros for Isabelle symbols \<bind> and \<then>
   327 (e.g. see ~~/src/HOL/Library/Monad_Syntax.thy).
   328 
   329 
   330 *** ML ***
   331 
   332 * The inner syntax of sort/type/term/prop supports inlined YXML
   333 representations within quoted string tokens.  By encoding logical
   334 entities via Term_XML (in ML or Scala) concrete syntax can be
   335 bypassed, which is particularly useful for producing bits of text
   336 under external program control.
   337 
   338 * Antiquotations for ML and document preparation are managed as theory
   339 data, which requires explicit setup.
   340 
   341 * Isabelle_Process.is_active allows tools to check if the official
   342 process wrapper is running (Isabelle/Scala/jEdit) or the old TTY loop
   343 (better known as Proof General).
   344 
   345 * Structure Proof_Context follows standard naming scheme.  Old
   346 ProofContext is still available for some time as legacy alias.
   347 
   348 * Structure Timing provides various operations for timing; supersedes
   349 former start_timing/end_timing etc.
   350 
   351 * Path.print is the official way to show file-system paths to users
   352 (including quotes etc.).
   353 
   354 * Inner syntax: identifiers in parse trees of generic categories
   355 "logic", "aprop", "idt" etc. carry position information (disguised as
   356 type constraints).  Occasional INCOMPATIBILITY with non-compliant
   357 translations that choke on unexpected type constraints.  Positions can
   358 be stripped in ML translations via Syntax.strip_positions /
   359 Syntax.strip_positions_ast, or via the syntax constant
   360 "_strip_positions" within parse trees.  As last resort, positions can
   361 be disabled via the configuration option Syntax.positions, which is
   362 called "syntax_positions" in Isar attribute syntax.
   363 
   364 * Discontinued special status of various ML structures that contribute
   365 to structure Syntax (Ast, Lexicon, Mixfix, Parser, Printer etc.): less
   366 pervasive content, no inclusion in structure Syntax.  INCOMPATIBILITY,
   367 refer directly to Ast.Constant, Lexicon.is_identifier,
   368 Syntax_Trans.mk_binder_tr etc.
   369 
   370 * Typed print translation: discontinued show_sorts argument, which is
   371 already available via context of "advanced" translation.
   372 
   373 * Refined PARALLEL_GOALS tactical: degrades gracefully for schematic
   374 goal states; body tactic needs to address all subgoals uniformly.
   375 
   376 * Slightly more special eq_list/eq_set, with shortcut involving
   377 pointer equality (assumes that eq relation is reflexive).
   378 
   379 * Classical tactics use proper Proof.context instead of historic types
   380 claset/clasimpset.  Old-style declarations like addIs, addEs, addDs
   381 operate directly on Proof.context.  Raw type claset retains its use as
   382 snapshot of the classical context, which can be recovered via
   383 (put_claset HOL_cs) etc.  Type clasimpset has been discontinued.
   384 INCOMPATIBILITY, classical tactics and derived proof methods require
   385 proper Proof.context.
   386 
   387 * Scala layer provides JVM method invocation service for static
   388 methods of type (String)String, see Invoke_Scala.method in ML.
   389 For example:
   390 
   391   Invoke_Scala.method "java.lang.System.getProperty" "java.home"
   392 
   393 
   394 
   395 New in Isabelle2011 (January 2011)
   396 ----------------------------------
   397 
   398 *** General ***
   399 
   400 * Experimental Prover IDE based on Isabelle/Scala and jEdit (see
   401 src/Tools/jEdit).  This also serves as IDE for Isabelle/ML, with
   402 useful tooltips and hyperlinks produced from its static analysis.  The
   403 bundled component provides an executable Isabelle tool that can be run
   404 like this:
   405 
   406   Isabelle2011/bin/isabelle jedit
   407 
   408 * Significantly improved Isabelle/Isar implementation manual.
   409 
   410 * System settings: ISABELLE_HOME_USER now includes ISABELLE_IDENTIFIER
   411 (and thus refers to something like $HOME/.isabelle/Isabelle2011),
   412 while the default heap location within that directory lacks that extra
   413 suffix.  This isolates multiple Isabelle installations from each
   414 other, avoiding problems with old settings in new versions.
   415 INCOMPATIBILITY, need to copy/upgrade old user settings manually.
   416 
   417 * Source files are always encoded as UTF-8, instead of old-fashioned
   418 ISO-Latin-1.  INCOMPATIBILITY.  Isabelle LaTeX documents might require
   419 the following package declarations:
   420 
   421   \usepackage[utf8]{inputenc}
   422   \usepackage{textcomp}
   423 
   424 * Explicit treatment of UTF-8 sequences as Isabelle symbols, such that
   425 a Unicode character is treated as a single symbol, not a sequence of
   426 non-ASCII bytes as before.  Since Isabelle/ML string literals may
   427 contain symbols without further backslash escapes, Unicode can now be
   428 used here as well.  Recall that Symbol.explode in ML provides a
   429 consistent view on symbols, while raw explode (or String.explode)
   430 merely give a byte-oriented representation.
   431 
   432 * Theory loader: source files are primarily located via the master
   433 directory of each theory node (where the .thy file itself resides).
   434 The global load path is still partially available as legacy feature.
   435 Minor INCOMPATIBILITY due to subtle change in file lookup: use
   436 explicit paths, relatively to the theory.
   437 
   438 * Special treatment of ML file names has been discontinued.
   439 Historically, optional extensions .ML or .sml were added on demand --
   440 at the cost of clarity of file dependencies.  Recall that Isabelle/ML
   441 files exclusively use the .ML extension.  Minor INCOMPATIBILTY.
   442 
   443 * Various options that affect pretty printing etc. are now properly
   444 handled within the context via configuration options, instead of
   445 unsynchronized references or print modes.  There are both ML Config.T
   446 entities and Isar declaration attributes to access these.
   447 
   448   ML (Config.T)                 Isar (attribute)
   449 
   450   eta_contract                  eta_contract
   451   show_brackets                 show_brackets
   452   show_sorts                    show_sorts
   453   show_types                    show_types
   454   show_question_marks           show_question_marks
   455   show_consts                   show_consts
   456   show_abbrevs                  show_abbrevs
   457 
   458   Syntax.ast_trace              syntax_ast_trace
   459   Syntax.ast_stat               syntax_ast_stat
   460   Syntax.ambiguity_level        syntax_ambiguity_level
   461 
   462   Goal_Display.goals_limit      goals_limit
   463   Goal_Display.show_main_goal   show_main_goal
   464 
   465   Method.rule_trace             rule_trace
   466 
   467   Thy_Output.display            thy_output_display
   468   Thy_Output.quotes             thy_output_quotes
   469   Thy_Output.indent             thy_output_indent
   470   Thy_Output.source             thy_output_source
   471   Thy_Output.break              thy_output_break
   472 
   473 Note that corresponding "..._default" references in ML may only be
   474 changed globally at the ROOT session setup, but *not* within a theory.
   475 The option "show_abbrevs" supersedes the former print mode
   476 "no_abbrevs" with inverted meaning.
   477 
   478 * More systematic naming of some configuration options.
   479 INCOMPATIBILITY.
   480 
   481   trace_simp  ~>  simp_trace
   482   debug_simp  ~>  simp_debug
   483 
   484 * Support for real valued configuration options, using simplistic
   485 floating-point notation that coincides with the inner syntax for
   486 float_token.
   487 
   488 * Support for real valued preferences (with approximative PGIP type):
   489 front-ends need to accept "pgint" values in float notation.
   490 INCOMPATIBILITY.
   491 
   492 * The IsabelleText font now includes Cyrillic, Hebrew, Arabic from
   493 DejaVu Sans.
   494 
   495 * Discontinued support for Poly/ML 5.0 and 5.1 versions.
   496 
   497 
   498 *** Pure ***
   499 
   500 * Command 'type_synonym' (with single argument) replaces somewhat
   501 outdated 'types', which is still available as legacy feature for some
   502 time.
   503 
   504 * Command 'nonterminal' (with 'and' separated list of arguments)
   505 replaces somewhat outdated 'nonterminals'.  INCOMPATIBILITY.
   506 
   507 * Command 'notepad' replaces former 'example_proof' for
   508 experimentation in Isar without any result.  INCOMPATIBILITY.
   509 
   510 * Locale interpretation commands 'interpret' and 'sublocale' accept
   511 lists of equations to map definitions in a locale to appropriate
   512 entities in the context of the interpretation.  The 'interpretation'
   513 command already provided this functionality.
   514 
   515 * Diagnostic command 'print_dependencies' prints the locale instances
   516 that would be activated if the specified expression was interpreted in
   517 the current context.  Variant "print_dependencies!" assumes a context
   518 without interpretations.
   519 
   520 * Diagnostic command 'print_interps' prints interpretations in proofs
   521 in addition to interpretations in theories.
   522 
   523 * Discontinued obsolete 'global' and 'local' commands to manipulate
   524 the theory name space.  Rare INCOMPATIBILITY.  The ML functions
   525 Sign.root_path and Sign.local_path may be applied directly where this
   526 feature is still required for historical reasons.
   527 
   528 * Discontinued obsolete 'constdefs' command.  INCOMPATIBILITY, use
   529 'definition' instead.
   530 
   531 * The "prems" fact, which refers to the accidental collection of
   532 foundational premises in the context, is now explicitly marked as
   533 legacy feature and will be discontinued soon.  Consider using "assms"
   534 of the head statement or reference facts by explicit names.
   535 
   536 * Document antiquotations @{class} and @{type} print classes and type
   537 constructors.
   538 
   539 * Document antiquotation @{file} checks file/directory entries within
   540 the local file system.
   541 
   542 
   543 *** HOL ***
   544 
   545 * Coercive subtyping: functions can be declared as coercions and type
   546 inference will add them as necessary upon input of a term.  Theory
   547 Complex_Main declares real :: nat => real and real :: int => real as
   548 coercions. A coercion function f is declared like this:
   549 
   550   declare [[coercion f]]
   551 
   552 To lift coercions through type constructors (e.g. from nat => real to
   553 nat list => real list), map functions can be declared, e.g.
   554 
   555   declare [[coercion_map map]]
   556 
   557 Currently coercion inference is activated only in theories including
   558 real numbers, i.e. descendants of Complex_Main.  This is controlled by
   559 the configuration option "coercion_enabled", e.g. it can be enabled in
   560 other theories like this:
   561 
   562   declare [[coercion_enabled]]
   563 
   564 * Command 'partial_function' provides basic support for recursive
   565 function definitions over complete partial orders.  Concrete instances
   566 are provided for i) the option type, ii) tail recursion on arbitrary
   567 types, and iii) the heap monad of Imperative_HOL.  See
   568 src/HOL/ex/Fundefs.thy and src/HOL/Imperative_HOL/ex/Linked_Lists.thy
   569 for examples.
   570 
   571 * Function package: f.psimps rules are no longer implicitly declared
   572 as [simp].  INCOMPATIBILITY.
   573 
   574 * Datatype package: theorems generated for executable equality (class
   575 "eq") carry proper names and are treated as default code equations.
   576 
   577 * Inductive package: now offers command 'inductive_simps' to
   578 automatically derive instantiated and simplified equations for
   579 inductive predicates, similar to 'inductive_cases'.
   580 
   581 * Command 'enriched_type' allows to register properties of the
   582 functorial structure of types.
   583 
   584 * Improved infrastructure for term evaluation using code generator
   585 techniques, in particular static evaluation conversions.
   586 
   587 * Code generator: Scala (2.8 or higher) has been added to the target
   588 languages.
   589 
   590 * Code generator: globbing constant expressions "*" and "Theory.*"
   591 have been replaced by the more idiomatic "_" and "Theory._".
   592 INCOMPATIBILITY.
   593 
   594 * Code generator: export_code without explicit file declaration prints
   595 to standard output.  INCOMPATIBILITY.
   596 
   597 * Code generator: do not print function definitions for case
   598 combinators any longer.
   599 
   600 * Code generator: simplification with rules determined with
   601 src/Tools/Code/code_simp.ML and method "code_simp".
   602 
   603 * Code generator for records: more idiomatic representation of record
   604 types.  Warning: records are not covered by ancient SML code
   605 generation any longer.  INCOMPATIBILITY.  In cases of need, a suitable
   606 rep_datatype declaration helps to succeed then:
   607 
   608   record 'a foo = ...
   609   ...
   610   rep_datatype foo_ext ...
   611 
   612 * Records: logical foundation type for records does not carry a
   613 '_type' suffix any longer (obsolete due to authentic syntax).
   614 INCOMPATIBILITY.
   615 
   616 * Quickcheck now by default uses exhaustive testing instead of random
   617 testing.  Random testing can be invoked by "quickcheck [random]",
   618 exhaustive testing by "quickcheck [exhaustive]".
   619 
   620 * Quickcheck instantiates polymorphic types with small finite
   621 datatypes by default. This enables a simple execution mechanism to
   622 handle quantifiers and function equality over the finite datatypes.
   623 
   624 * Quickcheck random generator has been renamed from "code" to
   625 "random".  INCOMPATIBILITY.
   626 
   627 * Quickcheck now has a configurable time limit which is set to 30
   628 seconds by default. This can be changed by adding [timeout = n] to the
   629 quickcheck command. The time limit for Auto Quickcheck is still set
   630 independently.
   631 
   632 * Quickcheck in locales considers interpretations of that locale for
   633 counter example search.
   634 
   635 * Sledgehammer:
   636   - Added "smt" and "remote_smt" provers based on the "smt" proof
   637     method. See the Sledgehammer manual for details ("isabelle doc
   638     sledgehammer").
   639   - Renamed commands:
   640     sledgehammer atp_info ~> sledgehammer running_provers
   641     sledgehammer atp_kill ~> sledgehammer kill_provers
   642     sledgehammer available_atps ~> sledgehammer available_provers
   643     INCOMPATIBILITY.
   644   - Renamed options:
   645     sledgehammer [atps = ...] ~> sledgehammer [provers = ...]
   646     sledgehammer [atp = ...] ~> sledgehammer [prover = ...]
   647     sledgehammer [timeout = 77 s] ~> sledgehammer [timeout = 77]
   648     (and "ms" and "min" are no longer supported)
   649     INCOMPATIBILITY.
   650 
   651 * Nitpick:
   652   - Renamed options:
   653     nitpick [timeout = 77 s] ~> nitpick [timeout = 77]
   654     nitpick [tac_timeout = 777 ms] ~> nitpick [tac_timeout = 0.777]
   655     INCOMPATIBILITY.
   656   - Added support for partial quotient types.
   657   - Added local versions of the "Nitpick.register_xxx" functions.
   658   - Added "whack" option.
   659   - Allow registration of quotient types as codatatypes.
   660   - Improved "merge_type_vars" option to merge more types.
   661   - Removed unsound "fast_descrs" option.
   662   - Added custom symmetry breaking for datatypes, making it possible to reach
   663     higher cardinalities.
   664   - Prevent the expansion of too large definitions.
   665 
   666 * Proof methods "metis" and "meson" now have configuration options
   667 "meson_trace", "metis_trace", and "metis_verbose" that can be enabled
   668 to diagnose these tools. E.g.
   669 
   670     using [[metis_trace = true]]
   671 
   672 * Auto Solve: Renamed "Auto Solve Direct".  The tool is now available
   673 manually as command 'solve_direct'.
   674 
   675 * The default SMT solver Z3 must be enabled explicitly (due to
   676 licensing issues) by setting the environment variable
   677 Z3_NON_COMMERCIAL in etc/settings of the component, for example.  For
   678 commercial applications, the SMT solver CVC3 is provided as fall-back;
   679 changing the SMT solver is done via the configuration option
   680 "smt_solver".
   681 
   682 * Remote SMT solvers need to be referred to by the "remote_" prefix,
   683 i.e. "remote_cvc3" and "remote_z3".
   684 
   685 * Added basic SMT support for datatypes, records, and typedefs using
   686 the oracle mode (no proofs).  Direct support of pairs has been dropped
   687 in exchange (pass theorems fst_conv snd_conv pair_collapse to the SMT
   688 support for a similar behavior).  Minor INCOMPATIBILITY.
   689 
   690 * Changed SMT configuration options:
   691   - Renamed:
   692     z3_proofs ~> smt_oracle (with inverted meaning)
   693     z3_trace_assms ~> smt_trace_used_facts
   694     INCOMPATIBILITY.
   695   - Added:
   696     smt_verbose
   697     smt_random_seed
   698     smt_datatypes
   699     smt_infer_triggers
   700     smt_monomorph_limit
   701     cvc3_options
   702     remote_cvc3_options
   703     remote_z3_options
   704     yices_options
   705 
   706 * Boogie output files (.b2i files) need to be declared in the theory
   707 header.
   708 
   709 * Simplification procedure "list_to_set_comprehension" rewrites list
   710 comprehensions applied to List.set to set comprehensions.  Occasional
   711 INCOMPATIBILITY, may be deactivated like this:
   712 
   713   declare [[simproc del: list_to_set_comprehension]]
   714 
   715 * Removed old version of primrec package.  INCOMPATIBILITY.
   716 
   717 * Removed simplifier congruence rule of "prod_case", as has for long
   718 been the case with "split".  INCOMPATIBILITY.
   719 
   720 * String.literal is a type, but not a datatype.  INCOMPATIBILITY.
   721 
   722 * Removed [split_format ... and ... and ...] version of
   723 [split_format].  Potential INCOMPATIBILITY.
   724 
   725 * Predicate "sorted" now defined inductively, with nice induction
   726 rules.  INCOMPATIBILITY: former sorted.simps now named sorted_simps.
   727 
   728 * Constant "contents" renamed to "the_elem", to free the generic name
   729 contents for other uses.  INCOMPATIBILITY.
   730 
   731 * Renamed class eq and constant eq (for code generation) to class
   732 equal and constant equal, plus renaming of related facts and various
   733 tuning.  INCOMPATIBILITY.
   734 
   735 * Dropped type classes mult_mono and mult_mono1.  INCOMPATIBILITY.
   736 
   737 * Removed output syntax "'a ~=> 'b" for "'a => 'b option".
   738 INCOMPATIBILITY.
   739 
   740 * Renamed theory Fset to Cset, type Fset.fset to Cset.set, in order to
   741 avoid confusion with finite sets.  INCOMPATIBILITY.
   742 
   743 * Abandoned locales equiv, congruent and congruent2 for equivalence
   744 relations.  INCOMPATIBILITY: use equivI rather than equiv_intro (same
   745 for congruent(2)).
   746 
   747 * Some previously unqualified names have been qualified:
   748 
   749   types
   750     bool ~> HOL.bool
   751     nat ~> Nat.nat
   752 
   753   constants
   754     Trueprop ~> HOL.Trueprop
   755     True ~> HOL.True
   756     False ~> HOL.False
   757     op & ~> HOL.conj
   758     op | ~> HOL.disj
   759     op --> ~> HOL.implies
   760     op = ~> HOL.eq
   761     Not ~> HOL.Not
   762     The ~> HOL.The
   763     All ~> HOL.All
   764     Ex ~> HOL.Ex
   765     Ex1 ~> HOL.Ex1
   766     Let ~> HOL.Let
   767     If ~> HOL.If
   768     Ball ~> Set.Ball
   769     Bex ~> Set.Bex
   770     Suc ~> Nat.Suc
   771     Pair ~> Product_Type.Pair
   772     fst ~> Product_Type.fst
   773     snd ~> Product_Type.snd
   774     curry ~> Product_Type.curry
   775     op : ~> Set.member
   776     Collect ~> Set.Collect
   777 
   778 INCOMPATIBILITY.
   779 
   780 * More canonical naming convention for some fundamental definitions:
   781 
   782     bot_bool_eq ~> bot_bool_def
   783     top_bool_eq ~> top_bool_def
   784     inf_bool_eq ~> inf_bool_def
   785     sup_bool_eq ~> sup_bool_def
   786     bot_fun_eq  ~> bot_fun_def
   787     top_fun_eq  ~> top_fun_def
   788     inf_fun_eq  ~> inf_fun_def
   789     sup_fun_eq  ~> sup_fun_def
   790 
   791 INCOMPATIBILITY.
   792 
   793 * More stylized fact names:
   794 
   795   expand_fun_eq ~> fun_eq_iff
   796   expand_set_eq ~> set_eq_iff
   797   set_ext       ~> set_eqI
   798   nat_number    ~> eval_nat_numeral
   799 
   800 INCOMPATIBILITY.
   801 
   802 * Refactoring of code-generation specific operations in theory List:
   803 
   804   constants
   805     null ~> List.null
   806 
   807   facts
   808     mem_iff ~> member_def
   809     null_empty ~> null_def
   810 
   811 INCOMPATIBILITY.  Note that these were not supposed to be used
   812 regularly unless for striking reasons; their main purpose was code
   813 generation.
   814 
   815 Various operations from the Haskell prelude are used for generating
   816 Haskell code.
   817 
   818 * Term "bij f" is now an abbreviation of "bij_betw f UNIV UNIV".  Term
   819 "surj f" is now an abbreviation of "range f = UNIV".  The theorems
   820 bij_def and surj_def are unchanged.  INCOMPATIBILITY.
   821 
   822 * Abolished some non-alphabetic type names: "prod" and "sum" replace
   823 "*" and "+" respectively.  INCOMPATIBILITY.
   824 
   825 * Name "Plus" of disjoint sum operator "<+>" is now hidden.  Write
   826 "Sum_Type.Plus" instead.
   827 
   828 * Constant "split" has been merged with constant "prod_case"; names of
   829 ML functions, facts etc. involving split have been retained so far,
   830 though.  INCOMPATIBILITY.
   831 
   832 * Dropped old infix syntax "_ mem _" for List.member; use "_ : set _"
   833 instead.  INCOMPATIBILITY.
   834 
   835 * Removed lemma "Option.is_none_none" which duplicates "is_none_def".
   836 INCOMPATIBILITY.
   837 
   838 * Former theory Library/Enum is now part of the HOL-Main image.
   839 INCOMPATIBILITY: all constants of the Enum theory now have to be
   840 referred to by its qualified name.
   841 
   842   enum    ~>  Enum.enum
   843   nlists  ~>  Enum.nlists
   844   product ~>  Enum.product
   845 
   846 * Theory Library/Monad_Syntax provides do-syntax for monad types.
   847 Syntax in Library/State_Monad has been changed to avoid ambiguities.
   848 INCOMPATIBILITY.
   849 
   850 * Theory Library/SetsAndFunctions has been split into
   851 Library/Function_Algebras and Library/Set_Algebras; canonical names
   852 for instance definitions for functions; various improvements.
   853 INCOMPATIBILITY.
   854 
   855 * Theory Library/Multiset provides stable quicksort implementation of
   856 sort_key.
   857 
   858 * Theory Library/Multiset: renamed empty_idemp ~> empty_neutral.
   859 INCOMPATIBILITY.
   860 
   861 * Session Multivariate_Analysis: introduced a type class for euclidean
   862 space.  Most theorems are now stated in terms of euclidean spaces
   863 instead of finite cartesian products.
   864 
   865   types
   866     real ^ 'n ~>  'a::real_vector
   867               ~>  'a::euclidean_space
   868               ~>  'a::ordered_euclidean_space
   869         (depends on your needs)
   870 
   871   constants
   872      _ $ _        ~> _ $$ _
   873      \<chi> x. _  ~> \<chi>\<chi> x. _
   874      CARD('n)     ~> DIM('a)
   875 
   876 Also note that the indices are now natural numbers and not from some
   877 finite type. Finite cartesian products of euclidean spaces, products
   878 of euclidean spaces the real and complex numbers are instantiated to
   879 be euclidean_spaces.  INCOMPATIBILITY.
   880 
   881 * Session Probability: introduced pextreal as positive extended real
   882 numbers.  Use pextreal as value for measures.  Introduce the
   883 Radon-Nikodym derivative, product spaces and Fubini's theorem for
   884 arbitrary sigma finite measures.  Introduces Lebesgue measure based on
   885 the integral in Multivariate Analysis.  INCOMPATIBILITY.
   886 
   887 * Session Imperative_HOL: revamped, corrected dozens of inadequacies.
   888 INCOMPATIBILITY.
   889 
   890 * Session SPARK (with image HOL-SPARK) provides commands to load and
   891 prove verification conditions generated by the SPARK Ada program
   892 verifier.  See also src/HOL/SPARK and src/HOL/SPARK/Examples.
   893 
   894 
   895 *** HOL-Algebra ***
   896 
   897 * Theorems for additive ring operations (locale abelian_monoid and
   898 descendants) are generated by interpretation from their multiplicative
   899 counterparts.  Names (in particular theorem names) have the mandatory
   900 qualifier 'add'.  Previous theorem names are redeclared for
   901 compatibility.
   902 
   903 * Structure "int_ring" is now an abbreviation (previously a
   904 definition).  This fits more natural with advanced interpretations.
   905 
   906 
   907 *** HOLCF ***
   908 
   909 * The domain package now runs in definitional mode by default: The
   910 former command 'new_domain' is now called 'domain'.  To use the domain
   911 package in its original axiomatic mode, use 'domain (unsafe)'.
   912 INCOMPATIBILITY.
   913 
   914 * The new class "domain" is now the default sort.  Class "predomain"
   915 is an unpointed version of "domain". Theories can be updated by
   916 replacing sort annotations as shown below.  INCOMPATIBILITY.
   917 
   918   'a::type ~> 'a::countable
   919   'a::cpo  ~> 'a::predomain
   920   'a::pcpo ~> 'a::domain
   921 
   922 * The old type class "rep" has been superseded by class "domain".
   923 Accordingly, users of the definitional package must remove any
   924 "default_sort rep" declarations.  INCOMPATIBILITY.
   925 
   926 * The domain package (definitional mode) now supports unpointed
   927 predomain argument types, as long as they are marked 'lazy'. (Strict
   928 arguments must be in class "domain".) For example, the following
   929 domain definition now works:
   930 
   931   domain natlist = nil | cons (lazy "nat discr") (lazy "natlist")
   932 
   933 * Theory HOLCF/Library/HOL_Cpo provides cpo and predomain class
   934 instances for types from main HOL: bool, nat, int, char, 'a + 'b,
   935 'a option, and 'a list.  Additionally, it configures fixrec and the
   936 domain package to work with these types.  For example:
   937 
   938   fixrec isInl :: "('a + 'b) u -> tr"
   939     where "isInl$(up$(Inl x)) = TT" | "isInl$(up$(Inr y)) = FF"
   940 
   941   domain V = VFun (lazy "V -> V") | VCon (lazy "nat") (lazy "V list")
   942 
   943 * The "(permissive)" option of fixrec has been replaced with a
   944 per-equation "(unchecked)" option. See
   945 src/HOL/HOLCF/Tutorial/Fixrec_ex.thy for examples. INCOMPATIBILITY.
   946 
   947 * The "bifinite" class no longer fixes a constant "approx"; the class
   948 now just asserts that such a function exists.  INCOMPATIBILITY.
   949 
   950 * Former type "alg_defl" has been renamed to "defl".  HOLCF no longer
   951 defines an embedding of type 'a defl into udom by default; instances
   952 of "bifinite" and "domain" classes are available in
   953 src/HOL/HOLCF/Library/Defl_Bifinite.thy.
   954 
   955 * The syntax "REP('a)" has been replaced with "DEFL('a)".
   956 
   957 * The predicate "directed" has been removed.  INCOMPATIBILITY.
   958 
   959 * The type class "finite_po" has been removed.  INCOMPATIBILITY.
   960 
   961 * The function "cprod_map" has been renamed to "prod_map".
   962 INCOMPATIBILITY.
   963 
   964 * The monadic bind operator on each powerdomain has new binder syntax
   965 similar to sets, e.g. "\<Union>\<sharp>x\<in>xs. t" represents
   966 "upper_bind\<cdot>xs\<cdot>(\<Lambda> x. t)".
   967 
   968 * The infix syntax for binary union on each powerdomain has changed
   969 from e.g. "+\<sharp>" to "\<union>\<sharp>", for consistency with set
   970 syntax.  INCOMPATIBILITY.
   971 
   972 * The constant "UU" has been renamed to "bottom".  The syntax "UU" is
   973 still supported as an input translation.
   974 
   975 * Renamed some theorems (the original names are also still available).
   976 
   977   expand_fun_below   ~> fun_below_iff
   978   below_fun_ext      ~> fun_belowI
   979   expand_cfun_eq     ~> cfun_eq_iff
   980   ext_cfun           ~> cfun_eqI
   981   expand_cfun_below  ~> cfun_below_iff
   982   below_cfun_ext     ~> cfun_belowI
   983   cont2cont_Rep_CFun ~> cont2cont_APP
   984 
   985 * The Abs and Rep functions for various types have changed names.
   986 Related theorem names have also changed to match. INCOMPATIBILITY.
   987 
   988   Rep_CFun  ~> Rep_cfun
   989   Abs_CFun  ~> Abs_cfun
   990   Rep_Sprod ~> Rep_sprod
   991   Abs_Sprod ~> Abs_sprod
   992   Rep_Ssum  ~> Rep_ssum
   993   Abs_Ssum  ~> Abs_ssum
   994 
   995 * Lemmas with names of the form *_defined_iff or *_strict_iff have
   996 been renamed to *_bottom_iff.  INCOMPATIBILITY.
   997 
   998 * Various changes to bisimulation/coinduction with domain package:
   999 
  1000   - Definitions of "bisim" constants no longer mention definedness.
  1001   - With mutual recursion, "bisim" predicate is now curried.
  1002   - With mutual recursion, each type gets a separate coind theorem.
  1003   - Variable names in bisim_def and coinduct rules have changed.
  1004 
  1005 INCOMPATIBILITY.
  1006 
  1007 * Case combinators generated by the domain package for type "foo" are
  1008 now named "foo_case" instead of "foo_when".  INCOMPATIBILITY.
  1009 
  1010 * Several theorems have been renamed to more accurately reflect the
  1011 names of constants and types involved.  INCOMPATIBILITY.
  1012 
  1013   thelub_const    ~> lub_const
  1014   lub_const       ~> is_lub_const
  1015   thelubI         ~> lub_eqI
  1016   is_lub_lub      ~> is_lubD2
  1017   lubI            ~> is_lub_lub
  1018   unique_lub      ~> is_lub_unique
  1019   is_ub_lub       ~> is_lub_rangeD1
  1020   lub_bin_chain   ~> is_lub_bin_chain
  1021   lub_fun         ~> is_lub_fun
  1022   thelub_fun      ~> lub_fun
  1023   thelub_cfun     ~> lub_cfun
  1024   thelub_Pair     ~> lub_Pair
  1025   lub_cprod       ~> is_lub_prod
  1026   thelub_cprod    ~> lub_prod
  1027   minimal_cprod   ~> minimal_prod
  1028   inst_cprod_pcpo ~> inst_prod_pcpo
  1029   UU_I            ~> bottomI
  1030   compact_UU      ~> compact_bottom
  1031   deflation_UU    ~> deflation_bottom
  1032   finite_deflation_UU ~> finite_deflation_bottom
  1033 
  1034 * Many legacy theorem names have been discontinued.  INCOMPATIBILITY.
  1035 
  1036   sq_ord_less_eq_trans ~> below_eq_trans
  1037   sq_ord_eq_less_trans ~> eq_below_trans
  1038   refl_less            ~> below_refl
  1039   trans_less           ~> below_trans
  1040   antisym_less         ~> below_antisym
  1041   antisym_less_inverse ~> po_eq_conv [THEN iffD1]
  1042   box_less             ~> box_below
  1043   rev_trans_less       ~> rev_below_trans
  1044   not_less2not_eq      ~> not_below2not_eq
  1045   less_UU_iff          ~> below_UU_iff
  1046   flat_less_iff        ~> flat_below_iff
  1047   adm_less             ~> adm_below
  1048   adm_not_less         ~> adm_not_below
  1049   adm_compact_not_less ~> adm_compact_not_below
  1050   less_fun_def         ~> below_fun_def
  1051   expand_fun_less      ~> fun_below_iff
  1052   less_fun_ext         ~> fun_belowI
  1053   less_discr_def       ~> below_discr_def
  1054   discr_less_eq        ~> discr_below_eq
  1055   less_unit_def        ~> below_unit_def
  1056   less_cprod_def       ~> below_prod_def
  1057   prod_lessI           ~> prod_belowI
  1058   Pair_less_iff        ~> Pair_below_iff
  1059   fst_less_iff         ~> fst_below_iff
  1060   snd_less_iff         ~> snd_below_iff
  1061   expand_cfun_less     ~> cfun_below_iff
  1062   less_cfun_ext        ~> cfun_belowI
  1063   injection_less       ~> injection_below
  1064   less_up_def          ~> below_up_def
  1065   not_Iup_less         ~> not_Iup_below
  1066   Iup_less             ~> Iup_below
  1067   up_less              ~> up_below
  1068   Def_inject_less_eq   ~> Def_below_Def
  1069   Def_less_is_eq       ~> Def_below_iff
  1070   spair_less_iff       ~> spair_below_iff
  1071   less_sprod           ~> below_sprod
  1072   spair_less           ~> spair_below
  1073   sfst_less_iff        ~> sfst_below_iff
  1074   ssnd_less_iff        ~> ssnd_below_iff
  1075   fix_least_less       ~> fix_least_below
  1076   dist_less_one        ~> dist_below_one
  1077   less_ONE             ~> below_ONE
  1078   ONE_less_iff         ~> ONE_below_iff
  1079   less_sinlD           ~> below_sinlD
  1080   less_sinrD           ~> below_sinrD
  1081 
  1082 
  1083 *** FOL and ZF ***
  1084 
  1085 * All constant names are now qualified internally and use proper
  1086 identifiers, e.g. "IFOL.eq" instead of "op =".  INCOMPATIBILITY.
  1087 
  1088 
  1089 *** ML ***
  1090 
  1091 * Antiquotation @{assert} inlines a function bool -> unit that raises
  1092 Fail if the argument is false.  Due to inlining the source position of
  1093 failed assertions is included in the error output.
  1094 
  1095 * Discontinued antiquotation @{theory_ref}, which is obsolete since ML
  1096 text is in practice always evaluated with a stable theory checkpoint.
  1097 Minor INCOMPATIBILITY, use (Theory.check_thy @{theory}) instead.
  1098 
  1099 * Antiquotation @{theory A} refers to theory A from the ancestry of
  1100 the current context, not any accidental theory loader state as before.
  1101 Potential INCOMPATIBILITY, subtle change in semantics.
  1102 
  1103 * Syntax.pretty_priority (default 0) configures the required priority
  1104 of pretty-printed output and thus affects insertion of parentheses.
  1105 
  1106 * Syntax.default_root (default "any") configures the inner syntax
  1107 category (nonterminal symbol) for parsing of terms.
  1108 
  1109 * Former exception Library.UnequalLengths now coincides with
  1110 ListPair.UnequalLengths.
  1111 
  1112 * Renamed structure MetaSimplifier to Raw_Simplifier.  Note that the
  1113 main functionality is provided by structure Simplifier.
  1114 
  1115 * Renamed raw "explode" function to "raw_explode" to emphasize its
  1116 meaning.  Note that internally to Isabelle, Symbol.explode is used in
  1117 almost all situations.
  1118 
  1119 * Discontinued obsolete function sys_error and exception SYS_ERROR.
  1120 See implementation manual for further details on exceptions in
  1121 Isabelle/ML.
  1122 
  1123 * Renamed setmp_noncritical to Unsynchronized.setmp to emphasize its
  1124 meaning.
  1125 
  1126 * Renamed structure PureThy to Pure_Thy and moved most of its
  1127 operations to structure Global_Theory, to emphasize that this is
  1128 rarely-used global-only stuff.
  1129 
  1130 * Discontinued Output.debug.  Minor INCOMPATIBILITY, use plain writeln
  1131 instead (or tracing for high-volume output).
  1132 
  1133 * Configuration option show_question_marks only affects regular pretty
  1134 printing of types and terms, not raw Term.string_of_vname.
  1135 
  1136 * ML_Context.thm and ML_Context.thms are no longer pervasive.  Rare
  1137 INCOMPATIBILITY, superseded by static antiquotations @{thm} and
  1138 @{thms} for most purposes.
  1139 
  1140 * ML structure Unsynchronized is never opened, not even in Isar
  1141 interaction mode as before.  Old Unsynchronized.set etc. have been
  1142 discontinued -- use plain := instead.  This should be *rare* anyway,
  1143 since modern tools always work via official context data, notably
  1144 configuration options.
  1145 
  1146 * Parallel and asynchronous execution requires special care concerning
  1147 interrupts.  Structure Exn provides some convenience functions that
  1148 avoid working directly with raw Interrupt.  User code must not absorb
  1149 interrupts -- intermediate handling (for cleanup etc.) needs to be
  1150 followed by re-raising of the original exception.  Another common
  1151 source of mistakes are "handle _" patterns, which make the meaning of
  1152 the program subject to physical effects of the environment.
  1153 
  1154 
  1155 
  1156 New in Isabelle2009-2 (June 2010)
  1157 ---------------------------------
  1158 
  1159 *** General ***
  1160 
  1161 * Authentic syntax for *all* logical entities (type classes, type
  1162 constructors, term constants): provides simple and robust
  1163 correspondence between formal entities and concrete syntax.  Within
  1164 the parse tree / AST representations, "constants" are decorated by
  1165 their category (class, type, const) and spelled out explicitly with
  1166 their full internal name.
  1167 
  1168 Substantial INCOMPATIBILITY concerning low-level syntax declarations
  1169 and translations (translation rules and translation functions in ML).
  1170 Some hints on upgrading:
  1171 
  1172   - Many existing uses of 'syntax' and 'translations' can be replaced
  1173     by more modern 'type_notation', 'notation' and 'abbreviation',
  1174     which are independent of this issue.
  1175 
  1176   - 'translations' require markup within the AST; the term syntax
  1177     provides the following special forms:
  1178 
  1179       CONST c   -- produces syntax version of constant c from context
  1180       XCONST c  -- literally c, checked as constant from context
  1181       c         -- literally c, if declared by 'syntax'
  1182 
  1183     Plain identifiers are treated as AST variables -- occasionally the
  1184     system indicates accidental variables via the error "rhs contains
  1185     extra variables".
  1186 
  1187     Type classes and type constructors are marked according to their
  1188     concrete syntax.  Some old translations rules need to be written
  1189     for the "type" category, using type constructor application
  1190     instead of pseudo-term application of the default category
  1191     "logic".
  1192 
  1193   - 'parse_translation' etc. in ML may use the following
  1194     antiquotations:
  1195 
  1196       @{class_syntax c}   -- type class c within parse tree / AST
  1197       @{term_syntax c}    -- type constructor c within parse tree / AST
  1198       @{const_syntax c}   -- ML version of "CONST c" above
  1199       @{syntax_const c}   -- literally c (checked wrt. 'syntax' declarations)
  1200 
  1201   - Literal types within 'typed_print_translations', i.e. those *not*
  1202     represented as pseudo-terms are represented verbatim.  Use @{class
  1203     c} or @{type_name c} here instead of the above syntax
  1204     antiquotations.
  1205 
  1206 Note that old non-authentic syntax was based on unqualified base
  1207 names, so all of the above "constant" names would coincide.  Recall
  1208 that 'print_syntax' and ML_command "set Syntax.trace_ast" help to
  1209 diagnose syntax problems.
  1210 
  1211 * Type constructors admit general mixfix syntax, not just infix.
  1212 
  1213 * Concrete syntax may be attached to local entities without a proof
  1214 body, too.  This works via regular mixfix annotations for 'fix',
  1215 'def', 'obtain' etc. or via the explicit 'write' command, which is
  1216 similar to the 'notation' command in theory specifications.
  1217 
  1218 * Discontinued unnamed infix syntax (legacy feature for many years) --
  1219 need to specify constant name and syntax separately.  Internal ML
  1220 datatype constructors have been renamed from InfixName to Infix etc.
  1221 Minor INCOMPATIBILITY.
  1222 
  1223 * Schematic theorem statements need to be explicitly markup as such,
  1224 via commands 'schematic_lemma', 'schematic_theorem',
  1225 'schematic_corollary'.  Thus the relevance of the proof is made
  1226 syntactically clear, which impacts performance in a parallel or
  1227 asynchronous interactive environment.  Minor INCOMPATIBILITY.
  1228 
  1229 * Use of cumulative prems via "!" in some proof methods has been
  1230 discontinued (old legacy feature).
  1231 
  1232 * References 'trace_simp' and 'debug_simp' have been replaced by
  1233 configuration options stored in the context. Enabling tracing (the
  1234 case of debugging is similar) in proofs works via
  1235 
  1236   using [[trace_simp = true]]
  1237 
  1238 Tracing is then active for all invocations of the simplifier in
  1239 subsequent goal refinement steps. Tracing may also still be enabled or
  1240 disabled via the ProofGeneral settings menu.
  1241 
  1242 * Separate commands 'hide_class', 'hide_type', 'hide_const',
  1243 'hide_fact' replace the former 'hide' KIND command.  Minor
  1244 INCOMPATIBILITY.
  1245 
  1246 * Improved parallelism of proof term normalization: usedir -p2 -q0 is
  1247 more efficient than combinations with -q1 or -q2.
  1248 
  1249 
  1250 *** Pure ***
  1251 
  1252 * Proofterms record type-class reasoning explicitly, using the
  1253 "unconstrain" operation internally.  This eliminates all sort
  1254 constraints from a theorem and proof, introducing explicit
  1255 OFCLASS-premises.  On the proof term level, this operation is
  1256 automatically applied at theorem boundaries, such that closed proofs
  1257 are always free of sort constraints.  INCOMPATIBILITY for tools that
  1258 inspect proof terms.
  1259 
  1260 * Local theory specifications may depend on extra type variables that
  1261 are not present in the result type -- arguments TYPE('a) :: 'a itself
  1262 are added internally.  For example:
  1263 
  1264   definition unitary :: bool where "unitary = (ALL (x::'a) y. x = y)"
  1265 
  1266 * Predicates of locales introduced by classes carry a mandatory
  1267 "class" prefix.  INCOMPATIBILITY.
  1268 
  1269 * Vacuous class specifications observe default sort.  INCOMPATIBILITY.
  1270 
  1271 * Old 'axclass' command has been discontinued.  INCOMPATIBILITY, use
  1272 'class' instead.
  1273 
  1274 * Command 'code_reflect' allows to incorporate generated ML code into
  1275 runtime environment; replaces immature code_datatype antiquotation.
  1276 INCOMPATIBILITY.
  1277 
  1278 * Code generator: simple concept for abstract datatypes obeying
  1279 invariants.
  1280 
  1281 * Code generator: details of internal data cache have no impact on the
  1282 user space functionality any longer.
  1283 
  1284 * Methods "unfold_locales" and "intro_locales" ignore non-locale
  1285 subgoals.  This is more appropriate for interpretations with 'where'.
  1286 INCOMPATIBILITY.
  1287 
  1288 * Command 'example_proof' opens an empty proof body.  This allows to
  1289 experiment with Isar, without producing any persistent result.
  1290 
  1291 * Commands 'type_notation' and 'no_type_notation' declare type syntax
  1292 within a local theory context, with explicit checking of the
  1293 constructors involved (in contrast to the raw 'syntax' versions).
  1294 
  1295 * Commands 'types' and 'typedecl' now work within a local theory
  1296 context -- without introducing dependencies on parameters or
  1297 assumptions, which is not possible in Isabelle/Pure.
  1298 
  1299 * Command 'defaultsort' has been renamed to 'default_sort', it works
  1300 within a local theory context.  Minor INCOMPATIBILITY.
  1301 
  1302 
  1303 *** HOL ***
  1304 
  1305 * Command 'typedef' now works within a local theory context -- without
  1306 introducing dependencies on parameters or assumptions, which is not
  1307 possible in Isabelle/Pure/HOL.  Note that the logical environment may
  1308 contain multiple interpretations of local typedefs (with different
  1309 non-emptiness proofs), even in a global theory context.
  1310 
  1311 * New package for quotient types.  Commands 'quotient_type' and
  1312 'quotient_definition' may be used for defining types and constants by
  1313 quotient constructions.  An example is the type of integers created by
  1314 quotienting pairs of natural numbers:
  1315 
  1316   fun
  1317     intrel :: "(nat * nat) => (nat * nat) => bool"
  1318   where
  1319     "intrel (x, y) (u, v) = (x + v = u + y)"
  1320 
  1321   quotient_type int = "nat * nat" / intrel
  1322     by (auto simp add: equivp_def expand_fun_eq)
  1323 
  1324   quotient_definition
  1325     "0::int" is "(0::nat, 0::nat)"
  1326 
  1327 The method "lifting" can be used to lift of theorems from the
  1328 underlying "raw" type to the quotient type.  The example
  1329 src/HOL/Quotient_Examples/FSet.thy includes such a quotient
  1330 construction and provides a reasoning infrastructure for finite sets.
  1331 
  1332 * Renamed Library/Quotient.thy to Library/Quotient_Type.thy to avoid
  1333 clash with new theory Quotient in Main HOL.
  1334 
  1335 * Moved the SMT binding into the main HOL session, eliminating
  1336 separate HOL-SMT session.
  1337 
  1338 * List membership infix mem operation is only an input abbreviation.
  1339 INCOMPATIBILITY.
  1340 
  1341 * Theory Library/Word.thy has been removed.  Use library Word/Word.thy
  1342 for future developements; former Library/Word.thy is still present in
  1343 the AFP entry RSAPPS.
  1344 
  1345 * Theorem Int.int_induct renamed to Int.int_of_nat_induct and is no
  1346 longer shadowed.  INCOMPATIBILITY.
  1347 
  1348 * Dropped theorem duplicate comp_arith; use semiring_norm instead.
  1349 INCOMPATIBILITY.
  1350 
  1351 * Dropped theorem RealPow.real_sq_order; use power2_le_imp_le instead.
  1352 INCOMPATIBILITY.
  1353 
  1354 * Dropped normalizing_semiring etc; use the facts in semiring classes
  1355 instead.  INCOMPATIBILITY.
  1356 
  1357 * Dropped several real-specific versions of lemmas about floor and
  1358 ceiling; use the generic lemmas from theory "Archimedean_Field"
  1359 instead.  INCOMPATIBILITY.
  1360 
  1361   floor_number_of_eq         ~> floor_number_of
  1362   le_floor_eq_number_of      ~> number_of_le_floor
  1363   le_floor_eq_zero           ~> zero_le_floor
  1364   le_floor_eq_one            ~> one_le_floor
  1365   floor_less_eq_number_of    ~> floor_less_number_of
  1366   floor_less_eq_zero         ~> floor_less_zero
  1367   floor_less_eq_one          ~> floor_less_one
  1368   less_floor_eq_number_of    ~> number_of_less_floor
  1369   less_floor_eq_zero         ~> zero_less_floor
  1370   less_floor_eq_one          ~> one_less_floor
  1371   floor_le_eq_number_of      ~> floor_le_number_of
  1372   floor_le_eq_zero           ~> floor_le_zero
  1373   floor_le_eq_one            ~> floor_le_one
  1374   floor_subtract_number_of   ~> floor_diff_number_of
  1375   floor_subtract_one         ~> floor_diff_one
  1376   ceiling_number_of_eq       ~> ceiling_number_of
  1377   ceiling_le_eq_number_of    ~> ceiling_le_number_of
  1378   ceiling_le_zero_eq         ~> ceiling_le_zero
  1379   ceiling_le_eq_one          ~> ceiling_le_one
  1380   less_ceiling_eq_number_of  ~> number_of_less_ceiling
  1381   less_ceiling_eq_zero       ~> zero_less_ceiling
  1382   less_ceiling_eq_one        ~> one_less_ceiling
  1383   ceiling_less_eq_number_of  ~> ceiling_less_number_of
  1384   ceiling_less_eq_zero       ~> ceiling_less_zero
  1385   ceiling_less_eq_one        ~> ceiling_less_one
  1386   le_ceiling_eq_number_of    ~> number_of_le_ceiling
  1387   le_ceiling_eq_zero         ~> zero_le_ceiling
  1388   le_ceiling_eq_one          ~> one_le_ceiling
  1389   ceiling_subtract_number_of ~> ceiling_diff_number_of
  1390   ceiling_subtract_one       ~> ceiling_diff_one
  1391 
  1392 * Theory "Finite_Set": various folding_XXX locales facilitate the
  1393 application of the various fold combinators on finite sets.
  1394 
  1395 * Library theory "RBT" renamed to "RBT_Impl"; new library theory "RBT"
  1396 provides abstract red-black tree type which is backed by "RBT_Impl" as
  1397 implementation.  INCOMPATIBILTY.
  1398 
  1399 * Theory Library/Coinductive_List has been removed -- superseded by
  1400 AFP/thys/Coinductive.
  1401 
  1402 * Theory PReal, including the type "preal" and related operations, has
  1403 been removed.  INCOMPATIBILITY.
  1404 
  1405 * Real: new development using Cauchy Sequences.
  1406 
  1407 * Split off theory "Big_Operators" containing setsum, setprod,
  1408 Inf_fin, Sup_fin, Min, Max from theory Finite_Set.  INCOMPATIBILITY.
  1409 
  1410 * Theory "Rational" renamed to "Rat", for consistency with "Nat",
  1411 "Int" etc.  INCOMPATIBILITY.
  1412 
  1413 * Constant Rat.normalize needs to be qualified.  INCOMPATIBILITY.
  1414 
  1415 * New set of rules "ac_simps" provides combined assoc / commute
  1416 rewrites for all interpretations of the appropriate generic locales.
  1417 
  1418 * Renamed theory "OrderedGroup" to "Groups" and split theory
  1419 "Ring_and_Field" into theories "Rings" and "Fields"; for more
  1420 appropriate and more consistent names suitable for name prefixes
  1421 within the HOL theories.  INCOMPATIBILITY.
  1422 
  1423 * Some generic constants have been put to appropriate theories:
  1424   - less_eq, less: Orderings
  1425   - zero, one, plus, minus, uminus, times, abs, sgn: Groups
  1426   - inverse, divide: Rings
  1427 INCOMPATIBILITY.
  1428 
  1429 * More consistent naming of type classes involving orderings (and
  1430 lattices):
  1431 
  1432     lower_semilattice                   ~> semilattice_inf
  1433     upper_semilattice                   ~> semilattice_sup
  1434 
  1435     dense_linear_order                  ~> dense_linorder
  1436 
  1437     pordered_ab_group_add               ~> ordered_ab_group_add
  1438     pordered_ab_group_add_abs           ~> ordered_ab_group_add_abs
  1439     pordered_ab_semigroup_add           ~> ordered_ab_semigroup_add
  1440     pordered_ab_semigroup_add_imp_le    ~> ordered_ab_semigroup_add_imp_le
  1441     pordered_cancel_ab_semigroup_add    ~> ordered_cancel_ab_semigroup_add
  1442     pordered_cancel_comm_semiring       ~> ordered_cancel_comm_semiring
  1443     pordered_cancel_semiring            ~> ordered_cancel_semiring
  1444     pordered_comm_monoid_add            ~> ordered_comm_monoid_add
  1445     pordered_comm_ring                  ~> ordered_comm_ring
  1446     pordered_comm_semiring              ~> ordered_comm_semiring
  1447     pordered_ring                       ~> ordered_ring
  1448     pordered_ring_abs                   ~> ordered_ring_abs
  1449     pordered_semiring                   ~> ordered_semiring
  1450 
  1451     ordered_ab_group_add                ~> linordered_ab_group_add
  1452     ordered_ab_semigroup_add            ~> linordered_ab_semigroup_add
  1453     ordered_cancel_ab_semigroup_add     ~> linordered_cancel_ab_semigroup_add
  1454     ordered_comm_semiring_strict        ~> linordered_comm_semiring_strict
  1455     ordered_field                       ~> linordered_field
  1456     ordered_field_no_lb                 ~> linordered_field_no_lb
  1457     ordered_field_no_ub                 ~> linordered_field_no_ub
  1458     ordered_field_dense_linear_order    ~> dense_linordered_field
  1459     ordered_idom                        ~> linordered_idom
  1460     ordered_ring                        ~> linordered_ring
  1461     ordered_ring_le_cancel_factor       ~> linordered_ring_le_cancel_factor
  1462     ordered_ring_less_cancel_factor     ~> linordered_ring_less_cancel_factor
  1463     ordered_ring_strict                 ~> linordered_ring_strict
  1464     ordered_semidom                     ~> linordered_semidom
  1465     ordered_semiring                    ~> linordered_semiring
  1466     ordered_semiring_1                  ~> linordered_semiring_1
  1467     ordered_semiring_1_strict           ~> linordered_semiring_1_strict
  1468     ordered_semiring_strict             ~> linordered_semiring_strict
  1469 
  1470   The following slightly odd type classes have been moved to a
  1471   separate theory Library/Lattice_Algebras:
  1472 
  1473     lordered_ab_group_add               ~> lattice_ab_group_add
  1474     lordered_ab_group_add_abs           ~> lattice_ab_group_add_abs
  1475     lordered_ab_group_add_meet          ~> semilattice_inf_ab_group_add
  1476     lordered_ab_group_add_join          ~> semilattice_sup_ab_group_add
  1477     lordered_ring                       ~> lattice_ring
  1478 
  1479 INCOMPATIBILITY.
  1480 
  1481 * Refined field classes:
  1482   - classes division_ring_inverse_zero, field_inverse_zero,
  1483     linordered_field_inverse_zero include rule inverse 0 = 0 --
  1484     subsumes former division_by_zero class;
  1485   - numerous lemmas have been ported from field to division_ring.
  1486 INCOMPATIBILITY.
  1487 
  1488 * Refined algebra theorem collections:
  1489   - dropped theorem group group_simps, use algebra_simps instead;
  1490   - dropped theorem group ring_simps, use field_simps instead;
  1491   - proper theorem collection field_simps subsumes former theorem
  1492     groups field_eq_simps and field_simps;
  1493   - dropped lemma eq_minus_self_iff which is a duplicate for
  1494     equal_neg_zero.
  1495 INCOMPATIBILITY.
  1496 
  1497 * Theory Finite_Set and List: some lemmas have been generalized from
  1498 sets to lattices:
  1499 
  1500   fun_left_comm_idem_inter      ~> fun_left_comm_idem_inf
  1501   fun_left_comm_idem_union      ~> fun_left_comm_idem_sup
  1502   inter_Inter_fold_inter        ~> inf_Inf_fold_inf
  1503   union_Union_fold_union        ~> sup_Sup_fold_sup
  1504   Inter_fold_inter              ~> Inf_fold_inf
  1505   Union_fold_union              ~> Sup_fold_sup
  1506   inter_INTER_fold_inter        ~> inf_INFI_fold_inf
  1507   union_UNION_fold_union        ~> sup_SUPR_fold_sup
  1508   INTER_fold_inter              ~> INFI_fold_inf
  1509   UNION_fold_union              ~> SUPR_fold_sup
  1510 
  1511 * Theory "Complete_Lattice": lemmas top_def and bot_def have been
  1512 replaced by the more convenient lemmas Inf_empty and Sup_empty.
  1513 Dropped lemmas Inf_insert_simp and Sup_insert_simp, which are subsumed
  1514 by Inf_insert and Sup_insert.  Lemmas Inf_UNIV and Sup_UNIV replace
  1515 former Inf_Univ and Sup_Univ.  Lemmas inf_top_right and sup_bot_right
  1516 subsume inf_top and sup_bot respectively.  INCOMPATIBILITY.
  1517 
  1518 * Reorganized theory Multiset: swapped notation of pointwise and
  1519 multiset order:
  1520 
  1521   - pointwise ordering is instance of class order with standard syntax
  1522     <= and <;
  1523   - multiset ordering has syntax <=# and <#; partial order properties
  1524     are provided by means of interpretation with prefix
  1525     multiset_order;
  1526   - less duplication, less historical organization of sections,
  1527     conversion from associations lists to multisets, rudimentary code
  1528     generation;
  1529   - use insert_DiffM2 [symmetric] instead of elem_imp_eq_diff_union,
  1530     if needed.
  1531 
  1532 Renamed:
  1533 
  1534   multiset_eq_conv_count_eq  ~>  multiset_ext_iff
  1535   multi_count_ext  ~>  multiset_ext
  1536   diff_union_inverse2  ~>  diff_union_cancelR
  1537 
  1538 INCOMPATIBILITY.
  1539 
  1540 * Theory Permutation: replaced local "remove" by List.remove1.
  1541 
  1542 * Code generation: ML and OCaml code is decorated with signatures.
  1543 
  1544 * Theory List: added transpose.
  1545 
  1546 * Library/Nat_Bijection.thy is a collection of bijective functions
  1547 between nat and other types, which supersedes the older libraries
  1548 Library/Nat_Int_Bij.thy and HOLCF/NatIso.thy.  INCOMPATIBILITY.
  1549 
  1550   Constants:
  1551   Nat_Int_Bij.nat2_to_nat         ~> prod_encode
  1552   Nat_Int_Bij.nat_to_nat2         ~> prod_decode
  1553   Nat_Int_Bij.int_to_nat_bij      ~> int_encode
  1554   Nat_Int_Bij.nat_to_int_bij      ~> int_decode
  1555   Countable.pair_encode           ~> prod_encode
  1556   NatIso.prod2nat                 ~> prod_encode
  1557   NatIso.nat2prod                 ~> prod_decode
  1558   NatIso.sum2nat                  ~> sum_encode
  1559   NatIso.nat2sum                  ~> sum_decode
  1560   NatIso.list2nat                 ~> list_encode
  1561   NatIso.nat2list                 ~> list_decode
  1562   NatIso.set2nat                  ~> set_encode
  1563   NatIso.nat2set                  ~> set_decode
  1564 
  1565   Lemmas:
  1566   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_decode
  1567   Nat_Int_Bij.nat2_to_nat_inj     ~> inj_prod_encode
  1568   Nat_Int_Bij.nat2_to_nat_surj    ~> surj_prod_encode
  1569   Nat_Int_Bij.nat_to_nat2_inj     ~> inj_prod_decode
  1570   Nat_Int_Bij.nat_to_nat2_surj    ~> surj_prod_decode
  1571   Nat_Int_Bij.i2n_n2i_id          ~> int_encode_inverse
  1572   Nat_Int_Bij.n2i_i2n_id          ~> int_decode_inverse
  1573   Nat_Int_Bij.surj_nat_to_int_bij ~> surj_int_encode
  1574   Nat_Int_Bij.surj_int_to_nat_bij ~> surj_int_decode
  1575   Nat_Int_Bij.inj_nat_to_int_bij  ~> inj_int_encode
  1576   Nat_Int_Bij.inj_int_to_nat_bij  ~> inj_int_decode
  1577   Nat_Int_Bij.bij_nat_to_int_bij  ~> bij_int_encode
  1578   Nat_Int_Bij.bij_int_to_nat_bij  ~> bij_int_decode
  1579 
  1580 * Sledgehammer:
  1581   - Renamed ATP commands:
  1582     atp_info     ~> sledgehammer running_atps
  1583     atp_kill     ~> sledgehammer kill_atps
  1584     atp_messages ~> sledgehammer messages
  1585     atp_minimize ~> sledgehammer minimize
  1586     print_atps   ~> sledgehammer available_atps
  1587     INCOMPATIBILITY.
  1588   - Added user's manual ("isabelle doc sledgehammer").
  1589   - Added option syntax and "sledgehammer_params" to customize
  1590     Sledgehammer's behavior.  See the manual for details.
  1591   - Modified the Isar proof reconstruction code so that it produces
  1592     direct proofs rather than proofs by contradiction.  (This feature
  1593     is still experimental.)
  1594   - Made Isar proof reconstruction work for SPASS, remote ATPs, and in
  1595     full-typed mode.
  1596   - Added support for TPTP syntax for SPASS via the "spass_tptp" ATP.
  1597 
  1598 * Nitpick:
  1599   - Added and implemented "binary_ints" and "bits" options.
  1600   - Added "std" option and implemented support for nonstandard models.
  1601   - Added and implemented "finitize" option to improve the precision
  1602     of infinite datatypes based on a monotonicity analysis.
  1603   - Added support for quotient types.
  1604   - Added support for "specification" and "ax_specification"
  1605     constructs.
  1606   - Added support for local definitions (for "function" and
  1607     "termination" proofs).
  1608   - Added support for term postprocessors.
  1609   - Optimized "Multiset.multiset" and "FinFun.finfun".
  1610   - Improved efficiency of "destroy_constrs" optimization.
  1611   - Fixed soundness bugs related to "destroy_constrs" optimization and
  1612     record getters.
  1613   - Fixed soundness bug related to higher-order constructors.
  1614   - Fixed soundness bug when "full_descrs" is enabled.
  1615   - Improved precision of set constructs.
  1616   - Added "atoms" option.
  1617   - Added cache to speed up repeated Kodkod invocations on the same
  1618     problems.
  1619   - Renamed "MiniSatJNI", "zChaffJNI", "BerkMinAlloy", and
  1620     "SAT4JLight" to "MiniSat_JNI", "zChaff_JNI", "BerkMin_Alloy", and
  1621     "SAT4J_Light".  INCOMPATIBILITY.
  1622   - Removed "skolemize", "uncurry", "sym_break", "flatten_prop",
  1623     "sharing_depth", and "show_skolems" options.  INCOMPATIBILITY.
  1624   - Removed "nitpick_intro" attribute.  INCOMPATIBILITY.
  1625 
  1626 * Method "induct" now takes instantiations of the form t, where t is not
  1627   a variable, as a shorthand for "x == t", where x is a fresh variable.
  1628   If this is not intended, t has to be enclosed in parentheses.
  1629   By default, the equalities generated by definitional instantiations
  1630   are pre-simplified, which may cause parameters of inductive cases
  1631   to disappear, or may even delete some of the inductive cases.
  1632   Use "induct (no_simp)" instead of "induct" to restore the old
  1633   behaviour. The (no_simp) option is also understood by the "cases"
  1634   and "nominal_induct" methods, which now perform pre-simplification, too.
  1635   INCOMPATIBILITY.
  1636 
  1637 
  1638 *** HOLCF ***
  1639 
  1640 * Variable names in lemmas generated by the domain package have
  1641 changed; the naming scheme is now consistent with the HOL datatype
  1642 package.  Some proof scripts may be affected, INCOMPATIBILITY.
  1643 
  1644 * The domain package no longer defines the function "foo_copy" for
  1645 recursive domain "foo".  The reach lemma is now stated directly in
  1646 terms of "foo_take".  Lemmas and proofs that mention "foo_copy" must
  1647 be reformulated in terms of "foo_take", INCOMPATIBILITY.
  1648 
  1649 * Most definedness lemmas generated by the domain package (previously
  1650 of the form "x ~= UU ==> foo$x ~= UU") now have an if-and-only-if form
  1651 like "foo$x = UU <-> x = UU", which works better as a simp rule.
  1652 Proofs that used definedness lemmas as intro rules may break,
  1653 potential INCOMPATIBILITY.
  1654 
  1655 * Induction and casedist rules generated by the domain package now
  1656 declare proper case_names (one called "bottom", and one named for each
  1657 constructor).  INCOMPATIBILITY.
  1658 
  1659 * For mutually-recursive domains, separate "reach" and "take_lemma"
  1660 rules are generated for each domain, INCOMPATIBILITY.
  1661 
  1662   foo_bar.reach       ~> foo.reach  bar.reach
  1663   foo_bar.take_lemmas ~> foo.take_lemma  bar.take_lemma
  1664 
  1665 * Some lemmas generated by the domain package have been renamed for
  1666 consistency with the datatype package, INCOMPATIBILITY.
  1667 
  1668   foo.ind        ~> foo.induct
  1669   foo.finite_ind ~> foo.finite_induct
  1670   foo.coind      ~> foo.coinduct
  1671   foo.casedist   ~> foo.exhaust
  1672   foo.exhaust    ~> foo.nchotomy
  1673 
  1674 * For consistency with other definition packages, the fixrec package
  1675 now generates qualified theorem names, INCOMPATIBILITY.
  1676 
  1677   foo_simps  ~> foo.simps
  1678   foo_unfold ~> foo.unfold
  1679   foo_induct ~> foo.induct
  1680 
  1681 * The "fixrec_simp" attribute has been removed.  The "fixrec_simp"
  1682 method and internal fixrec proofs now use the default simpset instead.
  1683 INCOMPATIBILITY.
  1684 
  1685 * The "contlub" predicate has been removed.  Proof scripts should use
  1686 lemma contI2 in place of monocontlub2cont, INCOMPATIBILITY.
  1687 
  1688 * The "admw" predicate has been removed, INCOMPATIBILITY.
  1689 
  1690 * The constants cpair, cfst, and csnd have been removed in favor of
  1691 Pair, fst, and snd from Isabelle/HOL, INCOMPATIBILITY.
  1692 
  1693 
  1694 *** ML ***
  1695 
  1696 * Antiquotations for basic formal entities:
  1697 
  1698     @{class NAME}         -- type class
  1699     @{class_syntax NAME}  -- syntax representation of the above
  1700 
  1701     @{type_name NAME}     -- logical type
  1702     @{type_abbrev NAME}   -- type abbreviation
  1703     @{nonterminal NAME}   -- type of concrete syntactic category
  1704     @{type_syntax NAME}   -- syntax representation of any of the above
  1705 
  1706     @{const_name NAME}    -- logical constant (INCOMPATIBILITY)
  1707     @{const_abbrev NAME}  -- abbreviated constant
  1708     @{const_syntax NAME}  -- syntax representation of any of the above
  1709 
  1710 * Antiquotation @{syntax_const NAME} ensures that NAME refers to a raw
  1711 syntax constant (cf. 'syntax' command).
  1712 
  1713 * Antiquotation @{make_string} inlines a function to print arbitrary
  1714 values similar to the ML toplevel.  The result is compiler dependent
  1715 and may fall back on "?" in certain situations.
  1716 
  1717 * Diagnostic commands 'ML_val' and 'ML_command' may refer to
  1718 antiquotations @{Isar.state} and @{Isar.goal}.  This replaces impure
  1719 Isar.state() and Isar.goal(), which belong to the old TTY loop and do
  1720 not work with the asynchronous Isar document model.
  1721 
  1722 * Configuration options now admit dynamic default values, depending on
  1723 the context or even global references.
  1724 
  1725 * SHA1.digest digests strings according to SHA-1 (see RFC 3174).  It
  1726 uses an efficient external library if available (for Poly/ML).
  1727 
  1728 * Renamed some important ML structures, while keeping the old names
  1729 for some time as aliases within the structure Legacy:
  1730 
  1731   OuterKeyword  ~>  Keyword
  1732   OuterLex      ~>  Token
  1733   OuterParse    ~>  Parse
  1734   OuterSyntax   ~>  Outer_Syntax
  1735   PrintMode     ~>  Print_Mode
  1736   SpecParse     ~>  Parse_Spec
  1737   ThyInfo       ~>  Thy_Info
  1738   ThyLoad       ~>  Thy_Load
  1739   ThyOutput     ~>  Thy_Output
  1740   TypeInfer     ~>  Type_Infer
  1741 
  1742 Note that "open Legacy" simplifies porting of sources, but forgetting
  1743 to remove it again will complicate porting again in the future.
  1744 
  1745 * Most operations that refer to a global context are named
  1746 accordingly, e.g. Simplifier.global_context or
  1747 ProofContext.init_global.  There are some situations where a global
  1748 context actually works, but under normal circumstances one needs to
  1749 pass the proper local context through the code!
  1750 
  1751 * Discontinued old TheoryDataFun with its copy/init operation -- data
  1752 needs to be pure.  Functor Theory_Data_PP retains the traditional
  1753 Pretty.pp argument to merge, which is absent in the standard
  1754 Theory_Data version.
  1755 
  1756 * Sorts.certify_sort and derived "cert" operations for types and terms
  1757 no longer minimize sorts.  Thus certification at the boundary of the
  1758 inference kernel becomes invariant under addition of class relations,
  1759 which is an important monotonicity principle.  Sorts are now minimized
  1760 in the syntax layer only, at the boundary between the end-user and the
  1761 system.  Subtle INCOMPATIBILITY, may have to use Sign.minimize_sort
  1762 explicitly in rare situations.
  1763 
  1764 * Renamed old-style Drule.standard to Drule.export_without_context, to
  1765 emphasize that this is in no way a standard operation.
  1766 INCOMPATIBILITY.
  1767 
  1768 * Subgoal.FOCUS (and variants): resulting goal state is normalized as
  1769 usual for resolution.  Rare INCOMPATIBILITY.
  1770 
  1771 * Renamed varify/unvarify operations to varify_global/unvarify_global
  1772 to emphasize that these only work in a global situation (which is
  1773 quite rare).
  1774 
  1775 * Curried take and drop in library.ML; negative length is interpreted
  1776 as infinity (as in chop).  Subtle INCOMPATIBILITY.
  1777 
  1778 * Proof terms: type substitutions on proof constants now use canonical
  1779 order of type variables.  INCOMPATIBILITY for tools working with proof
  1780 terms.
  1781 
  1782 * Raw axioms/defs may no longer carry sort constraints, and raw defs
  1783 may no longer carry premises.  User-level specifications are
  1784 transformed accordingly by Thm.add_axiom/add_def.
  1785 
  1786 
  1787 *** System ***
  1788 
  1789 * Discontinued special HOL_USEDIR_OPTIONS for the main HOL image;
  1790 ISABELLE_USEDIR_OPTIONS applies uniformly to all sessions.  Note that
  1791 proof terms are enabled unconditionally in the new HOL-Proofs image.
  1792 
  1793 * Discontinued old ISABELLE and ISATOOL environment settings (legacy
  1794 feature since Isabelle2009).  Use ISABELLE_PROCESS and ISABELLE_TOOL,
  1795 respectively.
  1796 
  1797 * Old lib/scripts/polyml-platform is superseded by the
  1798 ISABELLE_PLATFORM setting variable, which defaults to the 32 bit
  1799 variant, even on a 64 bit machine.  The following example setting
  1800 prefers 64 bit if available:
  1801 
  1802   ML_PLATFORM="${ISABELLE_PLATFORM64:-$ISABELLE_PLATFORM}"
  1803 
  1804 * The preliminary Isabelle/jEdit application demonstrates the emerging
  1805 Isabelle/Scala layer for advanced prover interaction and integration.
  1806 See src/Tools/jEdit or "isabelle jedit" provided by the properly built
  1807 component.
  1808 
  1809 * "IsabelleText" is a Unicode font derived from Bitstream Vera Mono
  1810 and Bluesky TeX fonts.  It provides the usual Isabelle symbols,
  1811 similar to the default assignment of the document preparation system
  1812 (cf. isabellesym.sty).  The Isabelle/Scala class Isabelle_System
  1813 provides some operations for direct access to the font without asking
  1814 the user for manual installation.
  1815 
  1816 
  1817 
  1818 New in Isabelle2009-1 (December 2009)
  1819 -------------------------------------
  1820 
  1821 *** General ***
  1822 
  1823 * Discontinued old form of "escaped symbols" such as \\<forall>.  Only
  1824 one backslash should be used, even in ML sources.
  1825 
  1826 
  1827 *** Pure ***
  1828 
  1829 * Locale interpretation propagates mixins along the locale hierarchy.
  1830 The currently only available mixins are the equations used to map
  1831 local definitions to terms of the target domain of an interpretation.
  1832 
  1833 * Reactivated diagnostic command 'print_interps'.  Use "print_interps
  1834 loc" to print all interpretations of locale "loc" in the theory.
  1835 Interpretations in proofs are not shown.
  1836 
  1837 * Thoroughly revised locales tutorial.  New section on conditional
  1838 interpretation.
  1839 
  1840 * On instantiation of classes, remaining undefined class parameters
  1841 are formally declared.  INCOMPATIBILITY.
  1842 
  1843 
  1844 *** Document preparation ***
  1845 
  1846 * New generalized style concept for printing terms: @{foo (style) ...}
  1847 instead of @{foo_style style ...}  (old form is still retained for
  1848 backward compatibility).  Styles can be also applied for
  1849 antiquotations prop, term_type and typeof.
  1850 
  1851 
  1852 *** HOL ***
  1853 
  1854 * New proof method "smt" for a combination of first-order logic with
  1855 equality, linear and nonlinear (natural/integer/real) arithmetic, and
  1856 fixed-size bitvectors; there is also basic support for higher-order
  1857 features (esp. lambda abstractions).  It is an incomplete decision
  1858 procedure based on external SMT solvers using the oracle mechanism;
  1859 for the SMT solver Z3, this method is proof-producing.  Certificates
  1860 are provided to avoid calling the external solvers solely for
  1861 re-checking proofs.  Due to a remote SMT service there is no need for
  1862 installing SMT solvers locally.  See src/HOL/SMT.
  1863 
  1864 * New commands to load and prove verification conditions generated by
  1865 the Boogie program verifier or derived systems (e.g. the Verifying C
  1866 Compiler (VCC) or Spec#).  See src/HOL/Boogie.
  1867 
  1868 * New counterexample generator tool 'nitpick' based on the Kodkod
  1869 relational model finder.  See src/HOL/Tools/Nitpick and
  1870 src/HOL/Nitpick_Examples.
  1871 
  1872 * New commands 'code_pred' and 'values' to invoke the predicate
  1873 compiler and to enumerate values of inductive predicates.
  1874 
  1875 * A tabled implementation of the reflexive transitive closure.
  1876 
  1877 * New implementation of quickcheck uses generic code generator;
  1878 default generators are provided for all suitable HOL types, records
  1879 and datatypes.  Old quickcheck can be re-activated importing theory
  1880 Library/SML_Quickcheck.
  1881 
  1882 * New testing tool Mirabelle for automated proof tools.  Applies
  1883 several tools and tactics like sledgehammer, metis, or quickcheck, to
  1884 every proof step in a theory.  To be used in batch mode via the
  1885 "mirabelle" utility.
  1886 
  1887 * New proof method "sos" (sum of squares) for nonlinear real
  1888 arithmetic (originally due to John Harison). It requires theory
  1889 Library/Sum_Of_Squares.  It is not a complete decision procedure but
  1890 works well in practice on quantifier-free real arithmetic with +, -,
  1891 *, ^, =, <= and <, i.e. boolean combinations of equalities and
  1892 inequalities between polynomials.  It makes use of external
  1893 semidefinite programming solvers.  Method "sos" generates a
  1894 certificate that can be pasted into the proof thus avoiding the need
  1895 to call an external tool every time the proof is checked.  See
  1896 src/HOL/Library/Sum_Of_Squares.
  1897 
  1898 * New method "linarith" invokes existing linear arithmetic decision
  1899 procedure only.
  1900 
  1901 * New command 'atp_minimal' reduces result produced by Sledgehammer.
  1902 
  1903 * New Sledgehammer option "Full Types" in Proof General settings menu.
  1904 Causes full type information to be output to the ATPs.  This slows
  1905 ATPs down considerably but eliminates a source of unsound "proofs"
  1906 that fail later.
  1907 
  1908 * New method "metisFT": A version of metis that uses full type
  1909 information in order to avoid failures of proof reconstruction.
  1910 
  1911 * New evaluator "approximate" approximates an real valued term using
  1912 the same method as the approximation method.
  1913 
  1914 * Method "approximate" now supports arithmetic expressions as
  1915 boundaries of intervals and implements interval splitting and Taylor
  1916 series expansion.
  1917 
  1918 * ML antiquotation @{code_datatype} inserts definition of a datatype
  1919 generated by the code generator; e.g. see src/HOL/Predicate.thy.
  1920 
  1921 * New theory SupInf of the supremum and infimum operators for sets of
  1922 reals.
  1923 
  1924 * New theory Probability, which contains a development of measure
  1925 theory, eventually leading to Lebesgue integration and probability.
  1926 
  1927 * Extended Multivariate Analysis to include derivation and Brouwer's
  1928 fixpoint theorem.
  1929 
  1930 * Reorganization of number theory, INCOMPATIBILITY:
  1931   - new number theory development for nat and int, in theories Divides
  1932     and GCD as well as in new session Number_Theory
  1933   - some constants and facts now suffixed with _nat and _int
  1934     accordingly
  1935   - former session NumberTheory now named Old_Number_Theory, including
  1936     theories Legacy_GCD and Primes (prefer Number_Theory if possible)
  1937   - moved theory Pocklington from src/HOL/Library to
  1938     src/HOL/Old_Number_Theory
  1939 
  1940 * Theory GCD includes functions Gcd/GCD and Lcm/LCM for the gcd and
  1941 lcm of finite and infinite sets. It is shown that they form a complete
  1942 lattice.
  1943 
  1944 * Class semiring_div requires superclass no_zero_divisors and proof of
  1945 div_mult_mult1; theorems div_mult_mult1, div_mult_mult2,
  1946 div_mult_mult1_if, div_mult_mult1 and div_mult_mult2 have been
  1947 generalized to class semiring_div, subsuming former theorems
  1948 zdiv_zmult_zmult1, zdiv_zmult_zmult1_if, zdiv_zmult_zmult1 and
  1949 zdiv_zmult_zmult2.  div_mult_mult1 is now [simp] by default.
  1950 INCOMPATIBILITY.
  1951 
  1952 * Refinements to lattice classes and sets:
  1953   - less default intro/elim rules in locale variant, more default
  1954     intro/elim rules in class variant: more uniformity
  1955   - lemma ge_sup_conv renamed to le_sup_iff, in accordance with
  1956     le_inf_iff
  1957   - dropped lemma alias inf_ACI for inf_aci (same for sup_ACI and
  1958     sup_aci)
  1959   - renamed ACI to inf_sup_aci
  1960   - new class "boolean_algebra"
  1961   - class "complete_lattice" moved to separate theory
  1962     "Complete_Lattice"; corresponding constants (and abbreviations)
  1963     renamed and with authentic syntax:
  1964     Set.Inf ~>    Complete_Lattice.Inf
  1965     Set.Sup ~>    Complete_Lattice.Sup
  1966     Set.INFI ~>   Complete_Lattice.INFI
  1967     Set.SUPR ~>   Complete_Lattice.SUPR
  1968     Set.Inter ~>  Complete_Lattice.Inter
  1969     Set.Union ~>  Complete_Lattice.Union
  1970     Set.INTER ~>  Complete_Lattice.INTER
  1971     Set.UNION ~>  Complete_Lattice.UNION
  1972   - authentic syntax for
  1973     Set.Pow
  1974     Set.image
  1975   - mere abbreviations:
  1976     Set.empty               (for bot)
  1977     Set.UNIV                (for top)
  1978     Set.inter               (for inf, formerly Set.Int)
  1979     Set.union               (for sup, formerly Set.Un)
  1980     Complete_Lattice.Inter  (for Inf)
  1981     Complete_Lattice.Union  (for Sup)
  1982     Complete_Lattice.INTER  (for INFI)
  1983     Complete_Lattice.UNION  (for SUPR)
  1984   - object-logic definitions as far as appropriate
  1985 
  1986 INCOMPATIBILITY.  Care is required when theorems Int_subset_iff or
  1987 Un_subset_iff are explicitly deleted as default simp rules; then also
  1988 their lattice counterparts le_inf_iff and le_sup_iff have to be
  1989 deleted to achieve the desired effect.
  1990 
  1991 * Rules inf_absorb1, inf_absorb2, sup_absorb1, sup_absorb2 are no simp
  1992 rules by default any longer; the same applies to min_max.inf_absorb1
  1993 etc.  INCOMPATIBILITY.
  1994 
  1995 * Rules sup_Int_eq and sup_Un_eq are no longer declared as
  1996 pred_set_conv by default.  INCOMPATIBILITY.
  1997 
  1998 * Power operations on relations and functions are now one dedicated
  1999 constant "compow" with infix syntax "^^".  Power operation on
  2000 multiplicative monoids retains syntax "^" and is now defined generic
  2001 in class power.  INCOMPATIBILITY.
  2002 
  2003 * Relation composition "R O S" now has a more standard argument order:
  2004 "R O S = {(x, z). EX y. (x, y) : R & (y, z) : S}".  INCOMPATIBILITY,
  2005 rewrite propositions with "S O R" --> "R O S". Proofs may occasionally
  2006 break, since the O_assoc rule was not rewritten like this.  Fix using
  2007 O_assoc[symmetric].  The same applies to the curried version "R OO S".
  2008 
  2009 * Function "Inv" is renamed to "inv_into" and function "inv" is now an
  2010 abbreviation for "inv_into UNIV".  Lemmas are renamed accordingly.
  2011 INCOMPATIBILITY.
  2012 
  2013 * Most rules produced by inductive and datatype package have mandatory
  2014 prefixes.  INCOMPATIBILITY.
  2015 
  2016 * Changed "DERIV_intros" to a dynamic fact, which can be augmented by
  2017 the attribute of the same name.  Each of the theorems in the list
  2018 DERIV_intros assumes composition with an additional function and
  2019 matches a variable to the derivative, which has to be solved by the
  2020 Simplifier.  Hence (auto intro!: DERIV_intros) computes the derivative
  2021 of most elementary terms.  Former Maclauren.DERIV_tac and
  2022 Maclauren.deriv_tac should be replaced by (auto intro!: DERIV_intros).
  2023 INCOMPATIBILITY.
  2024 
  2025 * Code generator attributes follow the usual underscore convention:
  2026     code_unfold     replaces    code unfold
  2027     code_post       replaces    code post
  2028     etc.
  2029   INCOMPATIBILITY.
  2030 
  2031 * Renamed methods:
  2032     sizechange -> size_change
  2033     induct_scheme -> induction_schema
  2034   INCOMPATIBILITY.
  2035 
  2036 * Discontinued abbreviation "arbitrary" of constant "undefined".
  2037 INCOMPATIBILITY, use "undefined" directly.
  2038 
  2039 * Renamed theorems:
  2040     Suc_eq_add_numeral_1 -> Suc_eq_plus1
  2041     Suc_eq_add_numeral_1_left -> Suc_eq_plus1_left
  2042     Suc_plus1 -> Suc_eq_plus1
  2043     *anti_sym -> *antisym*
  2044     vector_less_eq_def -> vector_le_def
  2045   INCOMPATIBILITY.
  2046 
  2047 * Added theorem List.map_map as [simp].  Removed List.map_compose.
  2048 INCOMPATIBILITY.
  2049 
  2050 * Removed predicate "M hassize n" (<--> card M = n & finite M).
  2051 INCOMPATIBILITY.
  2052 
  2053 
  2054 *** HOLCF ***
  2055 
  2056 * Theory Representable defines a class "rep" of domains that are
  2057 representable (via an ep-pair) in the universal domain type "udom".
  2058 Instances are provided for all type constructors defined in HOLCF.
  2059 
  2060 * The 'new_domain' command is a purely definitional version of the
  2061 domain package, for representable domains.  Syntax is identical to the
  2062 old domain package.  The 'new_domain' package also supports indirect
  2063 recursion using previously-defined type constructors.  See
  2064 src/HOLCF/ex/New_Domain.thy for examples.
  2065 
  2066 * Method "fixrec_simp" unfolds one step of a fixrec-defined constant
  2067 on the left-hand side of an equation, and then performs
  2068 simplification.  Rewriting is done using rules declared with the
  2069 "fixrec_simp" attribute.  The "fixrec_simp" method is intended as a
  2070 replacement for "fixpat"; see src/HOLCF/ex/Fixrec_ex.thy for examples.
  2071 
  2072 * The pattern-match compiler in 'fixrec' can now handle constructors
  2073 with HOL function types.  Pattern-match combinators for the Pair
  2074 constructor are pre-configured.
  2075 
  2076 * The 'fixrec' package now produces better fixed-point induction rules
  2077 for mutually-recursive definitions:  Induction rules have conclusions
  2078 of the form "P foo bar" instead of "P <foo, bar>".
  2079 
  2080 * The constant "sq_le" (with infix syntax "<<" or "\<sqsubseteq>") has
  2081 been renamed to "below".  The name "below" now replaces "less" in many
  2082 theorem names.  (Legacy theorem names using "less" are still supported
  2083 as well.)
  2084 
  2085 * The 'fixrec' package now supports "bottom patterns".  Bottom
  2086 patterns can be used to generate strictness rules, or to make
  2087 functions more strict (much like the bang-patterns supported by the
  2088 Glasgow Haskell Compiler).  See src/HOLCF/ex/Fixrec_ex.thy for
  2089 examples.
  2090 
  2091 
  2092 *** ML ***
  2093 
  2094 * Support for Poly/ML 5.3.0, with improved reporting of compiler
  2095 errors and run-time exceptions, including detailed source positions.
  2096 
  2097 * Structure Name_Space (formerly NameSpace) now manages uniquely
  2098 identified entries, with some additional information such as source
  2099 position, logical grouping etc.
  2100 
  2101 * Theory and context data is now introduced by the simplified and
  2102 modernized functors Theory_Data, Proof_Data, Generic_Data.  Data needs
  2103 to be pure, but the old TheoryDataFun for mutable data (with explicit
  2104 copy operation) is still available for some time.
  2105 
  2106 * Structure Synchronized (cf. src/Pure/Concurrent/synchronized.ML)
  2107 provides a high-level programming interface to synchronized state
  2108 variables with atomic update.  This works via pure function
  2109 application within a critical section -- its runtime should be as
  2110 short as possible; beware of deadlocks if critical code is nested,
  2111 either directly or indirectly via other synchronized variables!
  2112 
  2113 * Structure Unsynchronized (cf. src/Pure/ML-Systems/unsynchronized.ML)
  2114 wraps raw ML references, explicitly indicating their non-thread-safe
  2115 behaviour.  The Isar toplevel keeps this structure open, to
  2116 accommodate Proof General as well as quick and dirty interactive
  2117 experiments with references.
  2118 
  2119 * PARALLEL_CHOICE and PARALLEL_GOALS provide basic support for
  2120 parallel tactical reasoning.
  2121 
  2122 * Tacticals Subgoal.FOCUS, Subgoal.FOCUS_PREMS, Subgoal.FOCUS_PARAMS
  2123 are similar to SUBPROOF, but are slightly more flexible: only the
  2124 specified parts of the subgoal are imported into the context, and the
  2125 body tactic may introduce new subgoals and schematic variables.
  2126 
  2127 * Old tactical METAHYPS, which does not observe the proof context, has
  2128 been renamed to Old_Goals.METAHYPS and awaits deletion.  Use SUBPROOF
  2129 or Subgoal.FOCUS etc.
  2130 
  2131 * Renamed functor TableFun to Table, and GraphFun to Graph.  (Since
  2132 functors have their own ML name space there is no point to mark them
  2133 separately.)  Minor INCOMPATIBILITY.
  2134 
  2135 * Renamed NamedThmsFun to Named_Thms.  INCOMPATIBILITY.
  2136 
  2137 * Renamed several structures FooBar to Foo_Bar.  Occasional,
  2138 INCOMPATIBILITY.
  2139 
  2140 * Operations of structure Skip_Proof no longer require quick_and_dirty
  2141 mode, which avoids critical setmp.
  2142 
  2143 * Eliminated old Attrib.add_attributes, Method.add_methods and related
  2144 combinators for "args".  INCOMPATIBILITY, need to use simplified
  2145 Attrib/Method.setup introduced in Isabelle2009.
  2146 
  2147 * Proper context for simpset_of, claset_of, clasimpset_of.  May fall
  2148 back on global_simpset_of, global_claset_of, global_clasimpset_of as
  2149 last resort.  INCOMPATIBILITY.
  2150 
  2151 * Display.pretty_thm now requires a proper context (cf. former
  2152 ProofContext.pretty_thm).  May fall back on Display.pretty_thm_global
  2153 or even Display.pretty_thm_without_context as last resort.
  2154 INCOMPATIBILITY.
  2155 
  2156 * Discontinued Display.pretty_ctyp/cterm etc.  INCOMPATIBILITY, use
  2157 Syntax.pretty_typ/term directly, preferably with proper context
  2158 instead of global theory.
  2159 
  2160 
  2161 *** System ***
  2162 
  2163 * Further fine tuning of parallel proof checking, scales up to 8 cores
  2164 (max. speedup factor 5.0).  See also Goal.parallel_proofs in ML and
  2165 usedir option -q.
  2166 
  2167 * Support for additional "Isabelle components" via etc/components, see
  2168 also the system manual.
  2169 
  2170 * The isabelle makeall tool now operates on all components with
  2171 IsaMakefile, not just hardwired "logics".
  2172 
  2173 * Removed "compress" option from isabelle-process and isabelle usedir;
  2174 this is always enabled.
  2175 
  2176 * Discontinued support for Poly/ML 4.x versions.
  2177 
  2178 * Isabelle tool "wwwfind" provides web interface for 'find_theorems'
  2179 on a given logic image.  This requires the lighttpd webserver and is
  2180 currently supported on Linux only.
  2181 
  2182 
  2183 
  2184 New in Isabelle2009 (April 2009)
  2185 --------------------------------
  2186 
  2187 *** General ***
  2188 
  2189 * Simplified main Isabelle executables, with less surprises on
  2190 case-insensitive file-systems (such as Mac OS).
  2191 
  2192   - The main Isabelle tool wrapper is now called "isabelle" instead of
  2193     "isatool."
  2194 
  2195   - The former "isabelle" alias for "isabelle-process" has been
  2196     removed (should rarely occur to regular users).
  2197 
  2198   - The former "isabelle-interface" and its alias "Isabelle" have been
  2199     removed (interfaces are now regular Isabelle tools).
  2200 
  2201 Within scripts and make files, the Isabelle environment variables
  2202 ISABELLE_TOOL and ISABELLE_PROCESS replace old ISATOOL and ISABELLE,
  2203 respectively.  (The latter are still available as legacy feature.)
  2204 
  2205 The old isabelle-interface wrapper could react in confusing ways if
  2206 the interface was uninstalled or changed otherwise.  Individual
  2207 interface tool configuration is now more explicit, see also the
  2208 Isabelle system manual.  In particular, Proof General is now available
  2209 via "isabelle emacs".
  2210 
  2211 INCOMPATIBILITY, need to adapt derivative scripts.  Users may need to
  2212 purge installed copies of Isabelle executables and re-run "isabelle
  2213 install -p ...", or use symlinks.
  2214 
  2215 * The default for ISABELLE_HOME_USER is now ~/.isabelle instead of the
  2216 old ~/isabelle, which was slightly non-standard and apt to cause
  2217 surprises on case-insensitive file-systems (such as Mac OS).
  2218 
  2219 INCOMPATIBILITY, need to move existing ~/isabelle/etc,
  2220 ~/isabelle/heaps, ~/isabelle/browser_info to the new place.  Special
  2221 care is required when using older releases of Isabelle.  Note that
  2222 ISABELLE_HOME_USER can be changed in Isabelle/etc/settings of any
  2223 Isabelle distribution, in order to use the new ~/.isabelle uniformly.
  2224 
  2225 * Proofs of fully specified statements are run in parallel on
  2226 multi-core systems.  A speedup factor of 2.5 to 3.2 can be expected on
  2227 a regular 4-core machine, if the initial heap space is made reasonably
  2228 large (cf. Poly/ML option -H).  (Requires Poly/ML 5.2.1 or later.)
  2229 
  2230 * The main reference manuals ("isar-ref", "implementation", and
  2231 "system") have been updated and extended.  Formally checked references
  2232 as hyperlinks are now available uniformly.
  2233 
  2234 
  2235 *** Pure ***
  2236 
  2237 * Complete re-implementation of locales.  INCOMPATIBILITY in several
  2238 respects.  The most important changes are listed below.  See the
  2239 Tutorial on Locales ("locales" manual) for details.
  2240 
  2241 - In locale expressions, instantiation replaces renaming.  Parameters
  2242 must be declared in a for clause.  To aid compatibility with previous
  2243 parameter inheritance, in locale declarations, parameters that are not
  2244 'touched' (instantiation position "_" or omitted) are implicitly added
  2245 with their syntax at the beginning of the for clause.
  2246 
  2247 - Syntax from abbreviations and definitions in locales is available in
  2248 locale expressions and context elements.  The latter is particularly
  2249 useful in locale declarations.
  2250 
  2251 - More flexible mechanisms to qualify names generated by locale
  2252 expressions.  Qualifiers (prefixes) may be specified in locale
  2253 expressions, and can be marked as mandatory (syntax: "name!:") or
  2254 optional (syntax "name?:").  The default depends for plain "name:"
  2255 depends on the situation where a locale expression is used: in
  2256 commands 'locale' and 'sublocale' prefixes are optional, in
  2257 'interpretation' and 'interpret' prefixes are mandatory.  The old
  2258 implicit qualifiers derived from the parameter names of a locale are
  2259 no longer generated.
  2260 
  2261 - Command "sublocale l < e" replaces "interpretation l < e".  The
  2262 instantiation clause in "interpretation" and "interpret" (square
  2263 brackets) is no longer available.  Use locale expressions.
  2264 
  2265 - When converting proof scripts, mandatory qualifiers in
  2266 'interpretation' and 'interpret' should be retained by default, even
  2267 if this is an INCOMPATIBILITY compared to former behavior.  In the
  2268 worst case, use the "name?:" form for non-mandatory ones.  Qualifiers
  2269 in locale expressions range over a single locale instance only.
  2270 
  2271 - Dropped locale element "includes".  This is a major INCOMPATIBILITY.
  2272 In existing theorem specifications replace the includes element by the
  2273 respective context elements of the included locale, omitting those
  2274 that are already present in the theorem specification.  Multiple
  2275 assume elements of a locale should be replaced by a single one
  2276 involving the locale predicate.  In the proof body, declarations (most
  2277 notably theorems) may be regained by interpreting the respective
  2278 locales in the proof context as required (command "interpret").
  2279 
  2280 If using "includes" in replacement of a target solely because the
  2281 parameter types in the theorem are not as general as in the target,
  2282 consider declaring a new locale with additional type constraints on
  2283 the parameters (context element "constrains").
  2284 
  2285 - Discontinued "locale (open)".  INCOMPATIBILITY.
  2286 
  2287 - Locale interpretation commands no longer attempt to simplify goal.
  2288 INCOMPATIBILITY: in rare situations the generated goal differs.  Use
  2289 methods intro_locales and unfold_locales to clarify.
  2290 
  2291 - Locale interpretation commands no longer accept interpretation
  2292 attributes.  INCOMPATIBILITY.
  2293 
  2294 * Class declaration: so-called "base sort" must not be given in import
  2295 list any longer, but is inferred from the specification.  Particularly
  2296 in HOL, write
  2297 
  2298     class foo = ...
  2299 
  2300 instead of
  2301 
  2302     class foo = type + ...
  2303 
  2304 * Class target: global versions of theorems stemming do not carry a
  2305 parameter prefix any longer.  INCOMPATIBILITY.
  2306 
  2307 * Class 'instance' command no longer accepts attached definitions.
  2308 INCOMPATIBILITY, use proper 'instantiation' target instead.
  2309 
  2310 * Recovered hiding of consts, which was accidentally broken in
  2311 Isabelle2007.  Potential INCOMPATIBILITY, ``hide const c'' really
  2312 makes c inaccessible; consider using ``hide (open) const c'' instead.
  2313 
  2314 * Slightly more coherent Pure syntax, with updated documentation in
  2315 isar-ref manual.  Removed locales meta_term_syntax and
  2316 meta_conjunction_syntax: TERM and &&& (formerly &&) are now permanent,
  2317 INCOMPATIBILITY in rare situations.  Note that &&& should not be used
  2318 directly in regular applications.
  2319 
  2320 * There is a new syntactic category "float_const" for signed decimal
  2321 fractions (e.g. 123.45 or -123.45).
  2322 
  2323 * Removed exotic 'token_translation' command.  INCOMPATIBILITY, use ML
  2324 interface with 'setup' command instead.
  2325 
  2326 * Command 'local_setup' is similar to 'setup', but operates on a local
  2327 theory context.
  2328 
  2329 * The 'axiomatization' command now only works within a global theory
  2330 context.  INCOMPATIBILITY.
  2331 
  2332 * Goal-directed proof now enforces strict proof irrelevance wrt. sort
  2333 hypotheses.  Sorts required in the course of reasoning need to be
  2334 covered by the constraints in the initial statement, completed by the
  2335 type instance information of the background theory.  Non-trivial sort
  2336 hypotheses, which rarely occur in practice, may be specified via
  2337 vacuous propositions of the form SORT_CONSTRAINT('a::c).  For example:
  2338 
  2339   lemma assumes "SORT_CONSTRAINT('a::empty)" shows False ...
  2340 
  2341 The result contains an implicit sort hypotheses as before --
  2342 SORT_CONSTRAINT premises are eliminated as part of the canonical rule
  2343 normalization.
  2344 
  2345 * Generalized Isar history, with support for linear undo, direct state
  2346 addressing etc.
  2347 
  2348 * Changed defaults for unify configuration options:
  2349 
  2350   unify_trace_bound = 50 (formerly 25)
  2351   unify_search_bound = 60 (formerly 30)
  2352 
  2353 * Different bookkeeping for code equations (INCOMPATIBILITY):
  2354 
  2355   a) On theory merge, the last set of code equations for a particular
  2356      constant is taken (in accordance with the policy applied by other
  2357      parts of the code generator framework).
  2358 
  2359   b) Code equations stemming from explicit declarations (e.g. code
  2360      attribute) gain priority over default code equations stemming
  2361      from definition, primrec, fun etc.
  2362 
  2363 * Keyword 'code_exception' now named 'code_abort'.  INCOMPATIBILITY.
  2364 
  2365 * Unified theorem tables for both code generators.  Thus [code
  2366 func] has disappeared and only [code] remains.  INCOMPATIBILITY.
  2367 
  2368 * Command 'find_consts' searches for constants based on type and name
  2369 patterns, e.g.
  2370 
  2371     find_consts "_ => bool"
  2372 
  2373 By default, matching is against subtypes, but it may be restricted to
  2374 the whole type.  Searching by name is possible.  Multiple queries are
  2375 conjunctive and queries may be negated by prefixing them with a
  2376 hyphen:
  2377 
  2378     find_consts strict: "_ => bool" name: "Int" -"int => int"
  2379 
  2380 * New 'find_theorems' criterion "solves" matches theorems that
  2381 directly solve the current goal (modulo higher-order unification).
  2382 
  2383 * Auto solve feature for main theorem statements: whenever a new goal
  2384 is stated, "find_theorems solves" is called; any theorems that could
  2385 solve the lemma directly are listed as part of the goal state.
  2386 Cf. associated options in Proof General Isabelle settings menu,
  2387 enabled by default, with reasonable timeout for pathological cases of
  2388 higher-order unification.
  2389 
  2390 
  2391 *** Document preparation ***
  2392 
  2393 * Antiquotation @{lemma} now imitates a regular terminal proof,
  2394 demanding keyword 'by' and supporting the full method expression
  2395 syntax just like the Isar command 'by'.
  2396 
  2397 
  2398 *** HOL ***
  2399 
  2400 * Integrated main parts of former image HOL-Complex with HOL.  Entry
  2401 points Main and Complex_Main remain as before.
  2402 
  2403 * Logic image HOL-Plain provides a minimal HOL with the most important
  2404 tools available (inductive, datatype, primrec, ...).  This facilitates
  2405 experimentation and tool development.  Note that user applications
  2406 (and library theories) should never refer to anything below theory
  2407 Main, as before.
  2408 
  2409 * Logic image HOL-Main stops at theory Main, and thus facilitates
  2410 experimentation due to shorter build times.
  2411 
  2412 * Logic image HOL-NSA contains theories of nonstandard analysis which
  2413 were previously part of former HOL-Complex.  Entry point Hyperreal
  2414 remains valid, but theories formerly using Complex_Main should now use
  2415 new entry point Hypercomplex.
  2416 
  2417 * Generic ATP manager for Sledgehammer, based on ML threads instead of
  2418 Posix processes.  Avoids potentially expensive forking of the ML
  2419 process.  New thread-based implementation also works on non-Unix
  2420 platforms (Cygwin).  Provers are no longer hardwired, but defined
  2421 within the theory via plain ML wrapper functions.  Basic Sledgehammer
  2422 commands are covered in the isar-ref manual.
  2423 
  2424 * Wrapper scripts for remote SystemOnTPTP service allows to use
  2425 sledgehammer without local ATP installation (Vampire etc.). Other
  2426 provers may be included via suitable ML wrappers, see also
  2427 src/HOL/ATP_Linkup.thy.
  2428 
  2429 * ATP selection (E/Vampire/Spass) is now via Proof General's settings
  2430 menu.
  2431 
  2432 * The metis method no longer fails because the theorem is too trivial
  2433 (contains the empty clause).
  2434 
  2435 * The metis method now fails in the usual manner, rather than raising
  2436 an exception, if it determines that it cannot prove the theorem.
  2437 
  2438 * Method "coherent" implements a prover for coherent logic (see also
  2439 src/Tools/coherent.ML).
  2440 
  2441 * Constants "undefined" and "default" replace "arbitrary".  Usually
  2442 "undefined" is the right choice to replace "arbitrary", though
  2443 logically there is no difference.  INCOMPATIBILITY.
  2444 
  2445 * Command "value" now integrates different evaluation mechanisms.  The
  2446 result of the first successful evaluation mechanism is printed.  In
  2447 square brackets a particular named evaluation mechanisms may be
  2448 specified (currently, [SML], [code] or [nbe]).  See further
  2449 src/HOL/ex/Eval_Examples.thy.
  2450 
  2451 * Normalization by evaluation now allows non-leftlinear equations.
  2452 Declare with attribute [code nbe].
  2453 
  2454 * Methods "case_tac" and "induct_tac" now refer to the very same rules
  2455 as the structured Isar versions "cases" and "induct", cf. the
  2456 corresponding "cases" and "induct" attributes.  Mutual induction rules
  2457 are now presented as a list of individual projections
  2458 (e.g. foo_bar.inducts for types foo and bar); the old format with
  2459 explicit HOL conjunction is no longer supported.  INCOMPATIBILITY, in
  2460 rare situations a different rule is selected --- notably nested tuple
  2461 elimination instead of former prod.exhaust: use explicit (case_tac t
  2462 rule: prod.exhaust) here.
  2463 
  2464 * Attributes "cases", "induct", "coinduct" support "del" option.
  2465 
  2466 * Removed fact "case_split_thm", which duplicates "case_split".
  2467 
  2468 * The option datatype has been moved to a new theory Option.  Renamed
  2469 option_map to Option.map, and o2s to Option.set, INCOMPATIBILITY.
  2470 
  2471 * New predicate "strict_mono" classifies strict functions on partial
  2472 orders.  With strict functions on linear orders, reasoning about
  2473 (in)equalities is facilitated by theorems "strict_mono_eq",
  2474 "strict_mono_less_eq" and "strict_mono_less".
  2475 
  2476 * Some set operations are now proper qualified constants with
  2477 authentic syntax.  INCOMPATIBILITY:
  2478 
  2479     op Int ~>   Set.Int
  2480     op Un ~>    Set.Un
  2481     INTER ~>    Set.INTER
  2482     UNION ~>    Set.UNION
  2483     Inter ~>    Set.Inter
  2484     Union ~>    Set.Union
  2485     {} ~>       Set.empty
  2486     UNIV ~>     Set.UNIV
  2487 
  2488 * Class complete_lattice with operations Inf, Sup, INFI, SUPR now in
  2489 theory Set.
  2490 
  2491 * Auxiliary class "itself" has disappeared -- classes without any
  2492 parameter are treated as expected by the 'class' command.
  2493 
  2494 * Leibnitz's Series for Pi and the arcus tangens and logarithm series.
  2495 
  2496 * Common decision procedures (Cooper, MIR, Ferrack, Approximation,
  2497 Dense_Linear_Order) are now in directory HOL/Decision_Procs.
  2498 
  2499 * Theory src/HOL/Decision_Procs/Approximation provides the new proof
  2500 method "approximation".  It proves formulas on real values by using
  2501 interval arithmetic.  In the formulas are also the transcendental
  2502 functions sin, cos, tan, atan, ln, exp and the constant pi are
  2503 allowed. For examples see
  2504 src/HOL/Descision_Procs/ex/Approximation_Ex.thy.
  2505 
  2506 * Theory "Reflection" now resides in HOL/Library.
  2507 
  2508 * Entry point to Word library now simply named "Word".
  2509 INCOMPATIBILITY.
  2510 
  2511 * Made source layout more coherent with logical distribution
  2512 structure:
  2513 
  2514     src/HOL/Library/RType.thy ~> src/HOL/Typerep.thy
  2515     src/HOL/Library/Code_Message.thy ~> src/HOL/
  2516     src/HOL/Library/GCD.thy ~> src/HOL/
  2517     src/HOL/Library/Order_Relation.thy ~> src/HOL/
  2518     src/HOL/Library/Parity.thy ~> src/HOL/
  2519     src/HOL/Library/Univ_Poly.thy ~> src/HOL/
  2520     src/HOL/Real/ContNotDenum.thy ~> src/HOL/Library/
  2521     src/HOL/Real/Lubs.thy ~> src/HOL/
  2522     src/HOL/Real/PReal.thy ~> src/HOL/
  2523     src/HOL/Real/Rational.thy ~> src/HOL/
  2524     src/HOL/Real/RComplete.thy ~> src/HOL/
  2525     src/HOL/Real/RealDef.thy ~> src/HOL/
  2526     src/HOL/Real/RealPow.thy ~> src/HOL/
  2527     src/HOL/Real/Real.thy ~> src/HOL/
  2528     src/HOL/Complex/Complex_Main.thy ~> src/HOL/
  2529     src/HOL/Complex/Complex.thy ~> src/HOL/
  2530     src/HOL/Complex/FrechetDeriv.thy ~> src/HOL/Library/
  2531     src/HOL/Complex/Fundamental_Theorem_Algebra.thy ~> src/HOL/Library/
  2532     src/HOL/Hyperreal/Deriv.thy ~> src/HOL/
  2533     src/HOL/Hyperreal/Fact.thy ~> src/HOL/
  2534     src/HOL/Hyperreal/Integration.thy ~> src/HOL/
  2535     src/HOL/Hyperreal/Lim.thy ~> src/HOL/
  2536     src/HOL/Hyperreal/Ln.thy ~> src/HOL/
  2537     src/HOL/Hyperreal/Log.thy ~> src/HOL/
  2538     src/HOL/Hyperreal/MacLaurin.thy ~> src/HOL/
  2539     src/HOL/Hyperreal/NthRoot.thy ~> src/HOL/
  2540     src/HOL/Hyperreal/Series.thy ~> src/HOL/
  2541     src/HOL/Hyperreal/SEQ.thy ~> src/HOL/
  2542     src/HOL/Hyperreal/Taylor.thy ~> src/HOL/
  2543     src/HOL/Hyperreal/Transcendental.thy ~> src/HOL/
  2544     src/HOL/Real/Float ~> src/HOL/Library/
  2545     src/HOL/Real/HahnBanach ~> src/HOL/HahnBanach
  2546     src/HOL/Real/RealVector.thy ~> src/HOL/
  2547 
  2548     src/HOL/arith_data.ML ~> src/HOL/Tools
  2549     src/HOL/hologic.ML ~> src/HOL/Tools
  2550     src/HOL/simpdata.ML ~> src/HOL/Tools
  2551     src/HOL/int_arith1.ML ~> src/HOL/Tools/int_arith.ML
  2552     src/HOL/int_factor_simprocs.ML ~> src/HOL/Tools
  2553     src/HOL/nat_simprocs.ML ~> src/HOL/Tools
  2554     src/HOL/Real/float_arith.ML ~> src/HOL/Tools
  2555     src/HOL/Real/float_syntax.ML ~> src/HOL/Tools
  2556     src/HOL/Real/rat_arith.ML ~> src/HOL/Tools
  2557     src/HOL/Real/real_arith.ML ~> src/HOL/Tools
  2558 
  2559     src/HOL/Library/Array.thy ~> src/HOL/Imperative_HOL
  2560     src/HOL/Library/Heap_Monad.thy ~> src/HOL/Imperative_HOL
  2561     src/HOL/Library/Heap.thy ~> src/HOL/Imperative_HOL
  2562     src/HOL/Library/Imperative_HOL.thy ~> src/HOL/Imperative_HOL
  2563     src/HOL/Library/Ref.thy ~> src/HOL/Imperative_HOL
  2564     src/HOL/Library/Relational.thy ~> src/HOL/Imperative_HOL
  2565 
  2566 * If methods "eval" and "evaluation" encounter a structured proof
  2567 state with !!/==>, only the conclusion is evaluated to True (if
  2568 possible), avoiding strange error messages.
  2569 
  2570 * Method "sizechange" automates termination proofs using (a
  2571 modification of) the size-change principle.  Requires SAT solver.  See
  2572 src/HOL/ex/Termination.thy for examples.
  2573 
  2574 * Simplifier: simproc for let expressions now unfolds if bound
  2575 variable occurs at most once in let expression body.  INCOMPATIBILITY.
  2576 
  2577 * Method "arith": Linear arithmetic now ignores all inequalities when
  2578 fast_arith_neq_limit is exceeded, instead of giving up entirely.
  2579 
  2580 * New attribute "arith" for facts that should always be used
  2581 automatically by arithmetic. It is intended to be used locally in
  2582 proofs, e.g.
  2583 
  2584   assumes [arith]: "x > 0"
  2585 
  2586 Global usage is discouraged because of possible performance impact.
  2587 
  2588 * New classes "top" and "bot" with corresponding operations "top" and
  2589 "bot" in theory Orderings; instantiation of class "complete_lattice"
  2590 requires instantiation of classes "top" and "bot".  INCOMPATIBILITY.
  2591 
  2592 * Changed definition lemma "less_fun_def" in order to provide an
  2593 instance for preorders on functions; use lemma "less_le" instead.
  2594 INCOMPATIBILITY.
  2595 
  2596 * Theory Orderings: class "wellorder" moved here, with explicit
  2597 induction rule "less_induct" as assumption.  For instantiation of
  2598 "wellorder" by means of predicate "wf", use rule wf_wellorderI.
  2599 INCOMPATIBILITY.
  2600 
  2601 * Theory Orderings: added class "preorder" as superclass of "order".
  2602 INCOMPATIBILITY: Instantiation proofs for order, linorder
  2603 etc. slightly changed.  Some theorems named order_class.* now named
  2604 preorder_class.*.
  2605 
  2606 * Theory Relation: renamed "refl" to "refl_on", "reflexive" to "refl,
  2607 "diag" to "Id_on".
  2608 
  2609 * Theory Finite_Set: added a new fold combinator of type
  2610 
  2611   ('a => 'b => 'b) => 'b => 'a set => 'b
  2612 
  2613 Occasionally this is more convenient than the old fold combinator
  2614 which is now defined in terms of the new one and renamed to
  2615 fold_image.
  2616 
  2617 * Theories Ring_and_Field and OrderedGroup: The lemmas "group_simps"
  2618 and "ring_simps" have been replaced by "algebra_simps" (which can be
  2619 extended with further lemmas!).  At the moment both still exist but
  2620 the former will disappear at some point.
  2621 
  2622 * Theory Power: Lemma power_Suc is now declared as a simp rule in
  2623 class recpower.  Type-specific simp rules for various recpower types
  2624 have been removed.  INCOMPATIBILITY, rename old lemmas as follows:
  2625 
  2626 rat_power_0    -> power_0
  2627 rat_power_Suc  -> power_Suc
  2628 realpow_0      -> power_0
  2629 realpow_Suc    -> power_Suc
  2630 complexpow_0   -> power_0
  2631 complexpow_Suc -> power_Suc
  2632 power_poly_0   -> power_0
  2633 power_poly_Suc -> power_Suc
  2634 
  2635 * Theories Ring_and_Field and Divides: Definition of "op dvd" has been
  2636 moved to separate class dvd in Ring_and_Field; a couple of lemmas on
  2637 dvd has been generalized to class comm_semiring_1.  Likewise a bunch
  2638 of lemmas from Divides has been generalized from nat to class
  2639 semiring_div.  INCOMPATIBILITY.  This involves the following theorem
  2640 renames resulting from duplicate elimination:
  2641 
  2642     dvd_def_mod ~>          dvd_eq_mod_eq_0
  2643     zero_dvd_iff ~>         dvd_0_left_iff
  2644     dvd_0 ~>                dvd_0_right
  2645     DIVISION_BY_ZERO_DIV ~> div_by_0
  2646     DIVISION_BY_ZERO_MOD ~> mod_by_0
  2647     mult_div ~>             div_mult_self2_is_id
  2648     mult_mod ~>             mod_mult_self2_is_0
  2649 
  2650 * Theory IntDiv: removed many lemmas that are instances of class-based
  2651 generalizations (from Divides and Ring_and_Field).  INCOMPATIBILITY,
  2652 rename old lemmas as follows:
  2653 
  2654 dvd_diff               -> nat_dvd_diff
  2655 dvd_zminus_iff         -> dvd_minus_iff
  2656 mod_add1_eq            -> mod_add_eq
  2657 mod_mult1_eq           -> mod_mult_right_eq
  2658 mod_mult1_eq'          -> mod_mult_left_eq
  2659 mod_mult_distrib_mod   -> mod_mult_eq
  2660 nat_mod_add_left_eq    -> mod_add_left_eq
  2661 nat_mod_add_right_eq   -> mod_add_right_eq
  2662 nat_mod_div_trivial    -> mod_div_trivial
  2663 nat_mod_mod_trivial    -> mod_mod_trivial
  2664 zdiv_zadd_self1        -> div_add_self1
  2665 zdiv_zadd_self2        -> div_add_self2
  2666 zdiv_zmult_self1       -> div_mult_self2_is_id
  2667 zdiv_zmult_self2       -> div_mult_self1_is_id
  2668 zdvd_triv_left         -> dvd_triv_left
  2669 zdvd_triv_right        -> dvd_triv_right
  2670 zdvd_zmult_cancel_disj -> dvd_mult_cancel_left
  2671 zmod_eq0_zdvd_iff      -> dvd_eq_mod_eq_0[symmetric]
  2672 zmod_zadd_left_eq      -> mod_add_left_eq
  2673 zmod_zadd_right_eq     -> mod_add_right_eq
  2674 zmod_zadd_self1        -> mod_add_self1
  2675 zmod_zadd_self2        -> mod_add_self2
  2676 zmod_zadd1_eq          -> mod_add_eq
  2677 zmod_zdiff1_eq         -> mod_diff_eq
  2678 zmod_zdvd_zmod         -> mod_mod_cancel
  2679 zmod_zmod_cancel       -> mod_mod_cancel
  2680 zmod_zmult_self1       -> mod_mult_self2_is_0
  2681 zmod_zmult_self2       -> mod_mult_self1_is_0
  2682 zmod_1                 -> mod_by_1
  2683 zdiv_1                 -> div_by_1
  2684 zdvd_abs1              -> abs_dvd_iff
  2685 zdvd_abs2              -> dvd_abs_iff
  2686 zdvd_refl              -> dvd_refl
  2687 zdvd_trans             -> dvd_trans
  2688 zdvd_zadd              -> dvd_add
  2689 zdvd_zdiff             -> dvd_diff
  2690 zdvd_zminus_iff        -> dvd_minus_iff
  2691 zdvd_zminus2_iff       -> minus_dvd_iff
  2692 zdvd_zmultD            -> dvd_mult_right
  2693 zdvd_zmultD2           -> dvd_mult_left
  2694 zdvd_zmult_mono        -> mult_dvd_mono
  2695 zdvd_0_right           -> dvd_0_right
  2696 zdvd_0_left            -> dvd_0_left_iff
  2697 zdvd_1_left            -> one_dvd
  2698 zminus_dvd_iff         -> minus_dvd_iff
  2699 
  2700 * Theory Rational: 'Fract k 0' now equals '0'.  INCOMPATIBILITY.
  2701 
  2702 * The real numbers offer decimal input syntax: 12.34 is translated
  2703 into 1234/10^2. This translation is not reversed upon output.
  2704 
  2705 * Theory Library/Polynomial defines an abstract type 'a poly of
  2706 univariate polynomials with coefficients of type 'a.  In addition to
  2707 the standard ring operations, it also supports div and mod.  Code
  2708 generation is also supported, using list-style constructors.
  2709 
  2710 * Theory Library/Inner_Product defines a class of real_inner for real
  2711 inner product spaces, with an overloaded operation inner :: 'a => 'a
  2712 => real.  Class real_inner is a subclass of real_normed_vector from
  2713 theory RealVector.
  2714 
  2715 * Theory Library/Product_Vector provides instances for the product
  2716 type 'a * 'b of several classes from RealVector and Inner_Product.
  2717 Definitions of addition, subtraction, scalar multiplication, norms,
  2718 and inner products are included.
  2719 
  2720 * Theory Library/Bit defines the field "bit" of integers modulo 2.  In
  2721 addition to the field operations, numerals and case syntax are also
  2722 supported.
  2723 
  2724 * Theory Library/Diagonalize provides constructive version of Cantor's
  2725 first diagonalization argument.
  2726 
  2727 * Theory Library/GCD: Curried operations gcd, lcm (for nat) and zgcd,
  2728 zlcm (for int); carried together from various gcd/lcm developements in
  2729 the HOL Distribution.  Constants zgcd and zlcm replace former igcd and
  2730 ilcm; corresponding theorems renamed accordingly.  INCOMPATIBILITY,
  2731 may recover tupled syntax as follows:
  2732 
  2733     hide (open) const gcd
  2734     abbreviation gcd where
  2735       "gcd == (%(a, b). GCD.gcd a b)"
  2736     notation (output)
  2737       GCD.gcd ("gcd '(_, _')")
  2738 
  2739 The same works for lcm, zgcd, zlcm.
  2740 
  2741 * Theory Library/Nat_Infinity: added addition, numeral syntax and more
  2742 instantiations for algebraic structures.  Removed some duplicate
  2743 theorems.  Changes in simp rules.  INCOMPATIBILITY.
  2744 
  2745 * ML antiquotation @{code} takes a constant as argument and generates
  2746 corresponding code in background and inserts name of the corresponding
  2747 resulting ML value/function/datatype constructor binding in place.
  2748 All occurrences of @{code} with a single ML block are generated
  2749 simultaneously.  Provides a generic and safe interface for
  2750 instrumentalizing code generation.  See
  2751 src/HOL/Decision_Procs/Ferrack.thy for a more ambitious application.
  2752 In future you ought to refrain from ad-hoc compiling generated SML
  2753 code on the ML toplevel.  Note that (for technical reasons) @{code}
  2754 cannot refer to constants for which user-defined serializations are
  2755 set.  Refer to the corresponding ML counterpart directly in that
  2756 cases.
  2757 
  2758 * Command 'rep_datatype': instead of theorem names the command now
  2759 takes a list of terms denoting the constructors of the type to be
  2760 represented as datatype.  The characteristic theorems have to be
  2761 proven.  INCOMPATIBILITY.  Also observe that the following theorems
  2762 have disappeared in favour of existing ones:
  2763 
  2764     unit_induct                 ~> unit.induct
  2765     prod_induct                 ~> prod.induct
  2766     sum_induct                  ~> sum.induct
  2767     Suc_Suc_eq                  ~> nat.inject
  2768     Suc_not_Zero Zero_not_Suc   ~> nat.distinct
  2769 
  2770 
  2771 *** HOL-Algebra ***
  2772 
  2773 * New locales for orders and lattices where the equivalence relation
  2774 is not restricted to equality.  INCOMPATIBILITY: all order and lattice
  2775 locales use a record structure with field eq for the equivalence.
  2776 
  2777 * New theory of factorial domains.
  2778 
  2779 * Units_l_inv and Units_r_inv are now simp rules by default.
  2780 INCOMPATIBILITY.  Simplifier proof that require deletion of l_inv
  2781 and/or r_inv will now also require deletion of these lemmas.
  2782 
  2783 * Renamed the following theorems, INCOMPATIBILITY:
  2784 
  2785 UpperD ~> Upper_memD
  2786 LowerD ~> Lower_memD
  2787 least_carrier ~> least_closed
  2788 greatest_carrier ~> greatest_closed
  2789 greatest_Lower_above ~> greatest_Lower_below
  2790 one_zero ~> carrier_one_zero
  2791 one_not_zero ~> carrier_one_not_zero  (collision with assumption)
  2792 
  2793 
  2794 *** HOL-Nominal ***
  2795 
  2796 * Nominal datatypes can now contain type-variables.
  2797 
  2798 * Commands 'nominal_inductive' and 'equivariance' work with local
  2799 theory targets.
  2800 
  2801 * Nominal primrec can now works with local theory targets and its
  2802 specification syntax now conforms to the general format as seen in
  2803 'inductive' etc.
  2804 
  2805 * Method "perm_simp" honours the standard simplifier attributes
  2806 (no_asm), (no_asm_use) etc.
  2807 
  2808 * The new predicate #* is defined like freshness, except that on the
  2809 left hand side can be a set or list of atoms.
  2810 
  2811 * Experimental command 'nominal_inductive2' derives strong induction
  2812 principles for inductive definitions.  In contrast to
  2813 'nominal_inductive', which can only deal with a fixed number of
  2814 binders, it can deal with arbitrary expressions standing for sets of
  2815 atoms to be avoided.  The only inductive definition we have at the
  2816 moment that needs this generalisation is the typing rule for Lets in
  2817 the algorithm W:
  2818 
  2819  Gamma |- t1 : T1   (x,close Gamma T1)::Gamma |- t2 : T2   x#Gamma
  2820  -----------------------------------------------------------------
  2821          Gamma |- Let x be t1 in t2 : T2
  2822 
  2823 In this rule one wants to avoid all the binders that are introduced by
  2824 "close Gamma T1".  We are looking for other examples where this
  2825 feature might be useful.  Please let us know.
  2826 
  2827 
  2828 *** HOLCF ***
  2829 
  2830 * Reimplemented the simplification procedure for proving continuity
  2831 subgoals.  The new simproc is extensible; users can declare additional
  2832 continuity introduction rules with the attribute [cont2cont].
  2833 
  2834 * The continuity simproc now uses a different introduction rule for
  2835 solving continuity subgoals on terms with lambda abstractions.  In
  2836 some rare cases the new simproc may fail to solve subgoals that the
  2837 old one could solve, and "simp add: cont2cont_LAM" may be necessary.
  2838 Potential INCOMPATIBILITY.
  2839 
  2840 * Command 'fixrec': specification syntax now conforms to the general
  2841 format as seen in 'inductive' etc.  See src/HOLCF/ex/Fixrec_ex.thy for
  2842 examples.  INCOMPATIBILITY.
  2843 
  2844 
  2845 *** ZF ***
  2846 
  2847 * Proof of Zorn's Lemma for partial orders.
  2848 
  2849 
  2850 *** ML ***
  2851 
  2852 * Multithreading for Poly/ML 5.1/5.2 is no longer supported, only for
  2853 Poly/ML 5.2.1 or later.  Important note: the TimeLimit facility
  2854 depends on multithreading, so timouts will not work before Poly/ML
  2855 5.2.1!
  2856 
  2857 * High-level support for concurrent ML programming, see
  2858 src/Pure/Cuncurrent.  The data-oriented model of "future values" is
  2859 particularly convenient to organize independent functional
  2860 computations.  The concept of "synchronized variables" provides a
  2861 higher-order interface for components with shared state, avoiding the
  2862 delicate details of mutexes and condition variables.  (Requires
  2863 Poly/ML 5.2.1 or later.)
  2864 
  2865 * ML bindings produced via Isar commands are stored within the Isar
  2866 context (theory or proof).  Consequently, commands like 'use' and 'ML'
  2867 become thread-safe and work with undo as expected (concerning
  2868 top-level bindings, not side-effects on global references).
  2869 INCOMPATIBILITY, need to provide proper Isar context when invoking the
  2870 compiler at runtime; really global bindings need to be given outside a
  2871 theory.  (Requires Poly/ML 5.2 or later.)
  2872 
  2873 * Command 'ML_prf' is analogous to 'ML' but works within a proof
  2874 context.  Top-level ML bindings are stored within the proof context in
  2875 a purely sequential fashion, disregarding the nested proof structure.
  2876 ML bindings introduced by 'ML_prf' are discarded at the end of the
  2877 proof.  (Requires Poly/ML 5.2 or later.)
  2878 
  2879 * Simplified ML attribute and method setup, cf. functions Attrib.setup
  2880 and Method.setup, as well as Isar commands 'attribute_setup' and
  2881 'method_setup'.  INCOMPATIBILITY for 'method_setup', need to simplify
  2882 existing code accordingly, or use plain 'setup' together with old
  2883 Method.add_method.
  2884 
  2885 * Simplified ML oracle interface Thm.add_oracle promotes 'a -> cterm
  2886 to 'a -> thm, while results are always tagged with an authentic oracle
  2887 name.  The Isar command 'oracle' is now polymorphic, no argument type
  2888 is specified.  INCOMPATIBILITY, need to simplify existing oracle code
  2889 accordingly.  Note that extra performance may be gained by producing
  2890 the cterm carefully, avoiding slow Thm.cterm_of.
  2891 
  2892 * Simplified interface for defining document antiquotations via
  2893 ThyOutput.antiquotation, ThyOutput.output, and optionally
  2894 ThyOutput.maybe_pretty_source.  INCOMPATIBILITY, need to simplify user
  2895 antiquotations accordingly, see src/Pure/Thy/thy_output.ML for common
  2896 examples.
  2897 
  2898 * More systematic treatment of long names, abstract name bindings, and
  2899 name space operations.  Basic operations on qualified names have been
  2900 move from structure NameSpace to Long_Name, e.g. Long_Name.base_name,
  2901 Long_Name.append.  Old type bstring has been mostly replaced by
  2902 abstract type binding (see structure Binding), which supports precise
  2903 qualification by packages and local theory targets, as well as proper
  2904 tracking of source positions.  INCOMPATIBILITY, need to wrap old
  2905 bstring values into Binding.name, or better pass through abstract
  2906 bindings everywhere.  See further src/Pure/General/long_name.ML,
  2907 src/Pure/General/binding.ML and src/Pure/General/name_space.ML
  2908 
  2909 * Result facts (from PureThy.note_thms, ProofContext.note_thms,
  2910 LocalTheory.note etc.) now refer to the *full* internal name, not the
  2911 bstring as before.  INCOMPATIBILITY, not detected by ML type-checking!
  2912 
  2913 * Disposed old type and term read functions (Sign.read_def_typ,
  2914 Sign.read_typ, Sign.read_def_terms, Sign.read_term,
  2915 Thm.read_def_cterms, Thm.read_cterm etc.).  INCOMPATIBILITY, should
  2916 use regular Syntax.read_typ, Syntax.read_term, Syntax.read_typ_global,
  2917 Syntax.read_term_global etc.; see also OldGoals.read_term as last
  2918 resort for legacy applications.
  2919 
  2920 * Disposed old declarations, tactics, tactic combinators that refer to
  2921 the simpset or claset of an implicit theory (such as Addsimps,
  2922 Simp_tac, SIMPSET).  INCOMPATIBILITY, should use @{simpset} etc. in
  2923 embedded ML text, or local_simpset_of with a proper context passed as
  2924 explicit runtime argument.
  2925 
  2926 * Rules and tactics that read instantiations (read_instantiate,
  2927 res_inst_tac, thin_tac, subgoal_tac etc.) now demand a proper proof
  2928 context, which is required for parsing and type-checking.  Moreover,
  2929 the variables are specified as plain indexnames, not string encodings
  2930 thereof.  INCOMPATIBILITY.
  2931 
  2932 * Generic Toplevel.add_hook interface allows to analyze the result of
  2933 transactions.  E.g. see src/Pure/ProofGeneral/proof_general_pgip.ML
  2934 for theorem dependency output of transactions resulting in a new
  2935 theory state.
  2936 
  2937 * ML antiquotations: block-structured compilation context indicated by
  2938 \<lbrace> ... \<rbrace>; additional antiquotation forms:
  2939 
  2940   @{binding name}                         - basic name binding
  2941   @{let ?pat = term}                      - term abbreviation (HO matching)
  2942   @{note name = fact}                     - fact abbreviation
  2943   @{thm fact}                             - singleton fact (with attributes)
  2944   @{thms fact}                            - general fact (with attributes)
  2945   @{lemma prop by method}                 - singleton goal
  2946   @{lemma prop by meth1 meth2}            - singleton goal
  2947   @{lemma prop1 ... propN by method}      - general goal
  2948   @{lemma prop1 ... propN by meth1 meth2} - general goal
  2949   @{lemma (open) ...}                     - open derivation
  2950 
  2951 
  2952 *** System ***
  2953 
  2954 * The Isabelle "emacs" tool provides a specific interface to invoke
  2955 Proof General / Emacs, with more explicit failure if that is not
  2956 installed (the old isabelle-interface script silently falls back on
  2957 isabelle-process).  The PROOFGENERAL_HOME setting determines the
  2958 installation location of the Proof General distribution.
  2959 
  2960 * Isabelle/lib/classes/Pure.jar provides basic support to integrate
  2961 the Isabelle process into a JVM/Scala application.  See
  2962 Isabelle/lib/jedit/plugin for a minimal example.  (The obsolete Java
  2963 process wrapper has been discontinued.)
  2964 
  2965 * Added homegrown Isabelle font with unicode layout, see lib/fonts.
  2966 
  2967 * Various status messages (with exact source position information) are
  2968 emitted, if proper markup print mode is enabled.  This allows
  2969 user-interface components to provide detailed feedback on internal
  2970 prover operations.
  2971 
  2972 
  2973 
  2974 New in Isabelle2008 (June 2008)
  2975 -------------------------------
  2976 
  2977 *** General ***
  2978 
  2979 * The Isabelle/Isar Reference Manual (isar-ref) has been reorganized
  2980 and updated, with formally checked references as hyperlinks.
  2981 
  2982 * Theory loader: use_thy (and similar operations) no longer set the
  2983 implicit ML context, which was occasionally hard to predict and in
  2984 conflict with concurrency.  INCOMPATIBILITY, use ML within Isar which
  2985 provides a proper context already.
  2986 
  2987 * Theory loader: old-style ML proof scripts being *attached* to a thy
  2988 file are no longer supported.  INCOMPATIBILITY, regular 'uses' and
  2989 'use' within a theory file will do the job.
  2990 
  2991 * Name space merge now observes canonical order, i.e. the second space
  2992 is inserted into the first one, while existing entries in the first
  2993 space take precedence.  INCOMPATIBILITY in rare situations, may try to
  2994 swap theory imports.
  2995 
  2996 * Syntax: symbol \<chi> is now considered a letter.  Potential
  2997 INCOMPATIBILITY in identifier syntax etc.
  2998 
  2999 * Outer syntax: string tokens no longer admit escaped white space,
  3000 which was an accidental (undocumented) feature.  INCOMPATIBILITY, use
  3001 white space without escapes.
  3002 
  3003 * Outer syntax: string tokens may contain arbitrary character codes
  3004 specified via 3 decimal digits (as in SML).  E.g. "foo\095bar" for
  3005 "foo_bar".
  3006 
  3007 
  3008 *** Pure ***
  3009 
  3010 * Context-dependent token translations.  Default setup reverts locally
  3011 fixed variables, and adds hilite markup for undeclared frees.
  3012 
  3013 * Unused theorems can be found using the new command 'unused_thms'.
  3014 There are three ways of invoking it:
  3015 
  3016 (1) unused_thms
  3017      Only finds unused theorems in the current theory.
  3018 
  3019 (2) unused_thms thy_1 ... thy_n -
  3020      Finds unused theorems in the current theory and all of its ancestors,
  3021      excluding the theories thy_1 ... thy_n and all of their ancestors.
  3022 
  3023 (3) unused_thms thy_1 ... thy_n - thy'_1 ... thy'_m
  3024      Finds unused theorems in the theories thy'_1 ... thy'_m and all of
  3025      their ancestors, excluding the theories thy_1 ... thy_n and all of
  3026      their ancestors.
  3027 
  3028 In order to increase the readability of the list produced by
  3029 unused_thms, theorems that have been created by a particular instance
  3030 of a theory command such as 'inductive' or 'function' are considered
  3031 to belong to the same "group", meaning that if at least one theorem in
  3032 this group is used, the other theorems in the same group are no longer
  3033 reported as unused.  Moreover, if all theorems in the group are
  3034 unused, only one theorem in the group is displayed.
  3035 
  3036 Note that proof objects have to be switched on in order for
  3037 unused_thms to work properly (i.e. !proofs must be >= 1, which is
  3038 usually the case when using Proof General with the default settings).
  3039 
  3040 * Authentic naming of facts disallows ad-hoc overwriting of previous
  3041 theorems within the same name space.  INCOMPATIBILITY, need to remove
  3042 duplicate fact bindings, or even accidental fact duplications.  Note
  3043 that tools may maintain dynamically scoped facts systematically, using
  3044 PureThy.add_thms_dynamic.
  3045 
  3046 * Command 'hide' now allows to hide from "fact" name space as well.
  3047 
  3048 * Eliminated destructive theorem database, simpset, claset, and
  3049 clasimpset.  Potential INCOMPATIBILITY, really need to observe linear
  3050 update of theories within ML code.
  3051 
  3052 * Eliminated theory ProtoPure and CPure, leaving just one Pure theory.
  3053 INCOMPATIBILITY, object-logics depending on former Pure require
  3054 additional setup PureThy.old_appl_syntax_setup; object-logics
  3055 depending on former CPure need to refer to Pure.
  3056 
  3057 * Commands 'use' and 'ML' are now purely functional, operating on
  3058 theory/local_theory.  Removed former 'ML_setup' (on theory), use 'ML'
  3059 instead.  Added 'ML_val' as mere diagnostic replacement for 'ML'.
  3060 INCOMPATIBILITY.
  3061 
  3062 * Command 'setup': discontinued implicit version with ML reference.
  3063 
  3064 * Instantiation target allows for simultaneous specification of class
  3065 instance operations together with an instantiation proof.
  3066 Type-checking phase allows to refer to class operations uniformly.
  3067 See src/HOL/Complex/Complex.thy for an Isar example and
  3068 src/HOL/Library/Eval.thy for an ML example.
  3069 
  3070 * Indexing of literal facts: be more serious about including only
  3071 facts from the visible specification/proof context, but not the
  3072 background context (locale etc.).  Affects `prop` notation and method
  3073 "fact".  INCOMPATIBILITY: need to name facts explicitly in rare
  3074 situations.
  3075 
  3076 * Method "cases", "induct", "coinduct": removed obsolete/undocumented
  3077 "(open)" option, which used to expose internal bound variables to the
  3078 proof text.
  3079 
  3080 * Isar statements: removed obsolete case "rule_context".
  3081 INCOMPATIBILITY, better use explicit fixes/assumes.
  3082 
  3083 * Locale proofs: default proof step now includes 'unfold_locales';
  3084 hence 'proof' without argument may be used to unfold locale
  3085 predicates.
  3086 
  3087 
  3088 *** Document preparation ***
  3089 
  3090 * Simplified pdfsetup.sty: color/hyperref is used unconditionally for
  3091 both pdf and dvi (hyperlinks usually work in xdvi as well); removed
  3092 obsolete thumbpdf setup (contemporary PDF viewers do this on the
  3093 spot); renamed link color from "darkblue" to "linkcolor" (default
  3094 value unchanged, can be redefined via \definecolor); no longer sets
  3095 "a4paper" option (unnecessary or even intrusive).
  3096 
  3097 * Antiquotation @{lemma A method} proves proposition A by the given
  3098 method (either a method name or a method name plus (optional) method
  3099 arguments in parentheses) and prints A just like @{prop A}.
  3100 
  3101 
  3102 *** HOL ***
  3103 
  3104 * New primrec package.  Specification syntax conforms in style to
  3105 definition/function/....  No separate induction rule is provided.  The
  3106 "primrec" command distinguishes old-style and new-style specifications
  3107 by syntax.  The former primrec package is now named OldPrimrecPackage.
  3108 When adjusting theories, beware: constants stemming from new-style
  3109 primrec specifications have authentic syntax.
  3110 
  3111 * Metis prover is now an order of magnitude faster, and also works
  3112 with multithreading.
  3113 
  3114 * Metis: the maximum number of clauses that can be produced from a
  3115 theorem is now given by the attribute max_clauses.  Theorems that
  3116 exceed this number are ignored, with a warning printed.
  3117 
  3118 * Sledgehammer no longer produces structured proofs by default. To
  3119 enable, declare [[sledgehammer_full = true]].  Attributes
  3120 reconstruction_modulus, reconstruction_sorts renamed
  3121 sledgehammer_modulus, sledgehammer_sorts.  INCOMPATIBILITY.
  3122 
  3123 * Method "induct_scheme" derives user-specified induction rules
  3124 from well-founded induction and completeness of patterns. This factors
  3125 out some operations that are done internally by the function package
  3126 and makes them available separately.  See
  3127 src/HOL/ex/Induction_Scheme.thy for examples.
  3128 
  3129 * More flexible generation of measure functions for termination
  3130 proofs: Measure functions can be declared by proving a rule of the
  3131 form "is_measure f" and giving it the [measure_function] attribute.
  3132 The "is_measure" predicate is logically meaningless (always true), and
  3133 just guides the heuristic.  To find suitable measure functions, the
  3134 termination prover sets up the goal "is_measure ?f" of the appropriate
  3135 type and generates all solutions by prolog-style backwards proof using
  3136 the declared rules.
  3137 
  3138 This setup also deals with rules like 
  3139 
  3140   "is_measure f ==> is_measure (list_size f)"
  3141 
  3142 which accommodates nested datatypes that recurse through lists.
  3143 Similar rules are predeclared for products and option types.
  3144 
  3145 * Turned the type of sets "'a set" into an abbreviation for "'a => bool"
  3146 
  3147   INCOMPATIBILITIES:
  3148 
  3149   - Definitions of overloaded constants on sets have to be replaced by
  3150     definitions on => and bool.
  3151 
  3152   - Some definitions of overloaded operators on sets can now be proved
  3153     using the definitions of the operators on => and bool.  Therefore,
  3154     the following theorems have been renamed:
  3155 
  3156       subset_def   -> subset_eq
  3157       psubset_def  -> psubset_eq
  3158       set_diff_def -> set_diff_eq
  3159       Compl_def    -> Compl_eq
  3160       Sup_set_def  -> Sup_set_eq
  3161       Inf_set_def  -> Inf_set_eq
  3162       sup_set_def  -> sup_set_eq
  3163       inf_set_def  -> inf_set_eq
  3164 
  3165   - Due to the incompleteness of the HO unification algorithm, some
  3166     rules such as subst may require manual instantiation, if some of
  3167     the unknowns in the rule is a set.
  3168 
  3169   - Higher order unification and forward proofs:
  3170     The proof pattern
  3171 
  3172       have "P (S::'a set)" <...>
  3173       then have "EX S. P S" ..
  3174 
  3175     no longer works (due to the incompleteness of the HO unification
  3176     algorithm) and must be replaced by the pattern
  3177 
  3178       have "EX S. P S"
  3179       proof
  3180         show "P S" <...>
  3181       qed
  3182 
  3183   - Calculational reasoning with subst (or similar rules):
  3184     The proof pattern
  3185 
  3186       have "P (S::'a set)" <...>
  3187       also have "S = T" <...>
  3188       finally have "P T" .
  3189 
  3190     no longer works (for similar reasons as the previous example) and
  3191     must be replaced by something like
  3192 
  3193       have "P (S::'a set)" <...>
  3194       moreover have "S = T" <...>
  3195       ultimately have "P T" by simp
  3196 
  3197   - Tactics or packages written in ML code:
  3198     Code performing pattern matching on types via
  3199 
  3200       Type ("set", [T]) => ...
  3201 
  3202     must be rewritten. Moreover, functions like strip_type or
  3203     binder_types no longer return the right value when applied to a
  3204     type of the form
  3205 
  3206       T1 => ... => Tn => U => bool
  3207 
  3208     rather than
  3209 
  3210       T1 => ... => Tn => U set
  3211 
  3212 * Merged theories Wellfounded_Recursion, Accessible_Part and
  3213 Wellfounded_Relations to theory Wellfounded.
  3214 
  3215 * Explicit class "eq" for executable equality.  INCOMPATIBILITY.
  3216 
  3217 * Class finite no longer treats UNIV as class parameter.  Use class
  3218 enum from theory Library/Enum instead to achieve a similar effect.
  3219 INCOMPATIBILITY.
  3220 
  3221 * Theory List: rule list_induct2 now has explicitly named cases "Nil"
  3222 and "Cons".  INCOMPATIBILITY.
  3223 
  3224 * HOL (and FOL): renamed variables in rules imp_elim and swap.
  3225 Potential INCOMPATIBILITY.
  3226 
  3227 * Theory Product_Type: duplicated lemmas split_Pair_apply and
  3228 injective_fst_snd removed, use split_eta and prod_eqI instead.
  3229 Renamed upd_fst to apfst and upd_snd to apsnd.  INCOMPATIBILITY.
  3230 
  3231 * Theory Nat: removed redundant lemmas that merely duplicate lemmas of
  3232 the same name in theory Orderings:
  3233 
  3234   less_trans
  3235   less_linear
  3236   le_imp_less_or_eq
  3237   le_less_trans
  3238   less_le_trans
  3239   less_not_sym
  3240   less_asym
  3241 
  3242 Renamed less_imp_le to less_imp_le_nat, and less_irrefl to
  3243 less_irrefl_nat.  Potential INCOMPATIBILITY due to more general types
  3244 and different variable names.
  3245 
  3246 * Library/Option_ord.thy: Canonical order on option type.
  3247 
  3248 * Library/RBT.thy: Red-black trees, an efficient implementation of
  3249 finite maps.
  3250 
  3251 * Library/Countable.thy: Type class for countable types.
  3252 
  3253 * Theory Int: The representation of numerals has changed.  The infix
  3254 operator BIT and the bit datatype with constructors B0 and B1 have
  3255 disappeared.  INCOMPATIBILITY, use "Int.Bit0 x" and "Int.Bit1 y" in
  3256 place of "x BIT bit.B0" and "y BIT bit.B1", respectively.  Theorems
  3257 involving BIT, B0, or B1 have been renamed with "Bit0" or "Bit1"
  3258 accordingly.
  3259 
  3260 * Theory Nat: definition of <= and < on natural numbers no longer
  3261 depend on well-founded relations.  INCOMPATIBILITY.  Definitions
  3262 le_def and less_def have disappeared.  Consider lemmas not_less
  3263 [symmetric, where ?'a = nat] and less_eq [symmetric] instead.
  3264 
  3265 * Theory Finite_Set: locales ACf, ACe, ACIf, ACIfSL and ACIfSLlin
  3266 (whose purpose mainly is for various fold_set functionals) have been
  3267 abandoned in favor of the existing algebraic classes
  3268 ab_semigroup_mult, comm_monoid_mult, ab_semigroup_idem_mult,
  3269 lower_semilattice (resp. upper_semilattice) and linorder.
  3270 INCOMPATIBILITY.
  3271 
  3272 * Theory Transitive_Closure: induct and cases rules now declare proper
  3273 case_names ("base" and "step").  INCOMPATIBILITY.
  3274 
  3275 * Theorem Inductive.lfp_ordinal_induct generalized to complete
  3276 lattices.  The form set-specific version is available as
  3277 Inductive.lfp_ordinal_induct_set.
  3278 
  3279 * Renamed theorems "power.simps" to "power_int.simps".
  3280 INCOMPATIBILITY.
  3281 
  3282 * Class semiring_div provides basic abstract properties of semirings
  3283 with division and modulo operations.  Subsumes former class dvd_mod.
  3284 
  3285 * Merged theories IntDef, Numeral and IntArith into unified theory
  3286 Int.  INCOMPATIBILITY.
  3287 
  3288 * Theory Library/Code_Index: type "index" now represents natural
  3289 numbers rather than integers.  INCOMPATIBILITY.
  3290 
  3291 * New class "uminus" with operation "uminus" (split of from class
  3292 "minus" which now only has operation "minus", binary).
  3293 INCOMPATIBILITY.
  3294 
  3295 * Constants "card", "internal_split", "option_map" now with authentic
  3296 syntax.  INCOMPATIBILITY.
  3297 
  3298 * Definitions subset_def, psubset_def, set_diff_def, Compl_def,
  3299 le_bool_def, less_bool_def, le_fun_def, less_fun_def, inf_bool_def,
  3300 sup_bool_def, Inf_bool_def, Sup_bool_def, inf_fun_def, sup_fun_def,
  3301 Inf_fun_def, Sup_fun_def, inf_set_def, sup_set_def, Inf_set_def,
  3302 Sup_set_def, le_def, less_def, option_map_def now with object
  3303 equality.  INCOMPATIBILITY.
  3304 
  3305 * Records. Removed K_record, and replaced it by pure lambda term
  3306 %x. c. The simplifier setup is now more robust against eta expansion.
  3307 INCOMPATIBILITY: in cases explicitly referring to K_record.
  3308 
  3309 * Library/Multiset: {#a, b, c#} abbreviates {#a#} + {#b#} + {#c#}.
  3310 
  3311 * Library/ListVector: new theory of arithmetic vector operations.
  3312 
  3313 * Library/Order_Relation: new theory of various orderings as sets of
  3314 pairs.  Defines preorders, partial orders, linear orders and
  3315 well-orders on sets and on types.
  3316 
  3317 
  3318 *** ZF ***
  3319 
  3320 * Renamed some theories to allow to loading both ZF and HOL in the
  3321 same session:
  3322 
  3323   Datatype  -> Datatype_ZF
  3324   Inductive -> Inductive_ZF
  3325   Int       -> Int_ZF
  3326   IntDiv    -> IntDiv_ZF
  3327   Nat       -> Nat_ZF
  3328   List      -> List_ZF
  3329   Main      -> Main_ZF
  3330 
  3331 INCOMPATIBILITY: ZF theories that import individual theories below
  3332 Main might need to be adapted.  Regular theory Main is still
  3333 available, as trivial extension of Main_ZF.
  3334 
  3335 
  3336 *** ML ***
  3337 
  3338 * ML within Isar: antiquotation @{const name} or @{const
  3339 name(typargs)} produces statically-checked Const term.
  3340 
  3341 * Functor NamedThmsFun: data is available to the user as dynamic fact
  3342 (of the same name).  Removed obsolete print command.
  3343 
  3344 * Removed obsolete "use_legacy_bindings" function.
  3345 
  3346 * The ``print mode'' is now a thread-local value derived from a global
  3347 template (the former print_mode reference), thus access becomes
  3348 non-critical.  The global print_mode reference is for session
  3349 management only; user-code should use print_mode_value,
  3350 print_mode_active, PrintMode.setmp etc.  INCOMPATIBILITY.
  3351 
  3352 * Functions system/system_out provide a robust way to invoke external
  3353 shell commands, with propagation of interrupts (requires Poly/ML
  3354 5.2.1).  Do not use OS.Process.system etc. from the basis library!
  3355 
  3356 
  3357 *** System ***
  3358 
  3359 * Default settings: PROOFGENERAL_OPTIONS no longer impose xemacs ---
  3360 in accordance with Proof General 3.7, which prefers GNU emacs.
  3361 
  3362 * isatool tty runs Isabelle process with plain tty interaction;
  3363 optional line editor may be specified via ISABELLE_LINE_EDITOR
  3364 setting, the default settings attempt to locate "ledit" and "rlwrap".
  3365 
  3366 * isatool browser now works with Cygwin as well, using general
  3367 "javapath" function defined in Isabelle process environment.
  3368 
  3369 * YXML notation provides a simple and efficient alternative to
  3370 standard XML transfer syntax.  See src/Pure/General/yxml.ML and
  3371 isatool yxml as described in the Isabelle system manual.
  3372 
  3373 * JVM class isabelle.IsabelleProcess (located in Isabelle/lib/classes)
  3374 provides general wrapper for managing an Isabelle process in a robust
  3375 fashion, with ``cooked'' output from stdin/stderr.
  3376 
  3377 * Rudimentary Isabelle plugin for jEdit (see Isabelle/lib/jedit),
  3378 based on Isabelle/JVM process wrapper (see Isabelle/lib/classes).
  3379 
  3380 * Removed obsolete THIS_IS_ISABELLE_BUILD feature.  NB: the documented
  3381 way of changing the user's settings is via
  3382 ISABELLE_HOME_USER/etc/settings, which is a fully featured bash
  3383 script.
  3384 
  3385 * Multithreading.max_threads := 0 refers to the number of actual CPU
  3386 cores of the underlying machine, which is a good starting point for
  3387 optimal performance tuning.  The corresponding usedir option -M allows
  3388 "max" as an alias for "0".  WARNING: does not work on certain versions
  3389 of Mac OS (with Poly/ML 5.1).
  3390 
  3391 * isabelle-process: non-ML sessions are run with "nice", to reduce the
  3392 adverse effect of Isabelle flooding interactive front-ends (notably
  3393 ProofGeneral / XEmacs).
  3394 
  3395 
  3396 
  3397 New in Isabelle2007 (November 2007)
  3398 -----------------------------------
  3399 
  3400 *** General ***
  3401 
  3402 * More uniform information about legacy features, notably a
  3403 warning/error of "Legacy feature: ...", depending on the state of the
  3404 tolerate_legacy_features flag (default true). FUTURE INCOMPATIBILITY:
  3405 legacy features will disappear eventually.
  3406 
  3407 * Theory syntax: the header format ``theory A = B + C:'' has been
  3408 discontinued in favour of ``theory A imports B C begin''.  Use isatool
  3409 fixheaders to convert existing theory files.  INCOMPATIBILITY.
  3410 
  3411 * Theory syntax: the old non-Isar theory file format has been
  3412 discontinued altogether.  Note that ML proof scripts may still be used
  3413 with Isar theories; migration is usually quite simple with the ML
  3414 function use_legacy_bindings.  INCOMPATIBILITY.
  3415 
  3416 * Theory syntax: some popular names (e.g. 'class', 'declaration',
  3417 'fun', 'help', 'if') are now keywords.  INCOMPATIBILITY, use double
  3418 quotes.
  3419 
  3420 * Theory loader: be more serious about observing the static theory
  3421 header specifications (including optional directories), but not the
  3422 accidental file locations of previously successful loads.  The strict
  3423 update policy of former update_thy is now already performed by
  3424 use_thy, so the former has been removed; use_thys updates several
  3425 theories simultaneously, just as 'imports' within a theory header
  3426 specification, but without merging the results.  Potential
  3427 INCOMPATIBILITY: may need to refine theory headers and commands
  3428 ROOT.ML which depend on load order.
  3429 
  3430 * Theory loader: optional support for content-based file
  3431 identification, instead of the traditional scheme of full physical
  3432 path plus date stamp; configured by the ISABELLE_FILE_IDENT setting
  3433 (cf. the system manual).  The new scheme allows to work with
  3434 non-finished theories in persistent session images, such that source
  3435 files may be moved later on without requiring reloads.
  3436 
  3437 * Theory loader: old-style ML proof scripts being *attached* to a thy
  3438 file (with the same base name as the theory) are considered a legacy
  3439 feature, which will disappear eventually. Even now, the theory loader
  3440 no longer maintains dependencies on such files.
  3441 
  3442 * Syntax: the scope for resolving ambiguities via type-inference is
  3443 now limited to individual terms, instead of whole simultaneous
  3444 specifications as before. This greatly reduces the complexity of the
  3445 syntax module and improves flexibility by separating parsing and
  3446 type-checking. INCOMPATIBILITY: additional type-constraints (explicit
  3447 'fixes' etc.) are required in rare situations.
  3448 
  3449 * Syntax: constants introduced by new-style packages ('definition',
  3450 'abbreviation' etc.) are passed through the syntax module in
  3451 ``authentic mode''. This means that associated mixfix annotations
  3452 really stick to such constants, independently of potential name space
  3453 ambiguities introduced later on. INCOMPATIBILITY: constants in parse
  3454 trees are represented slightly differently, may need to adapt syntax
  3455 translations accordingly. Use CONST marker in 'translations' and
  3456 @{const_syntax} antiquotation in 'parse_translation' etc.
  3457 
  3458 * Legacy goal package: reduced interface to the bare minimum required
  3459 to keep existing proof scripts running.  Most other user-level
  3460 functions are now part of the OldGoals structure, which is *not* open
  3461 by default (consider isatool expandshort before open OldGoals).
  3462 Removed top_sg, prin, printyp, pprint_term/typ altogether, because
  3463 these tend to cause confusion about the actual goal (!) context being
  3464 used here, which is not necessarily the same as the_context().
  3465 
  3466 * Command 'find_theorems': supports "*" wild-card in "name:"
  3467 criterion; "with_dups" option.  Certain ProofGeneral versions might
  3468 support a specific search form (see ProofGeneral/CHANGES).
  3469 
  3470 * The ``prems limit'' option (cf. ProofContext.prems_limit) is now -1
  3471 by default, which means that "prems" (and also "fixed variables") are
  3472 suppressed from proof state output.  Note that the ProofGeneral
  3473 settings mechanism allows to change and save options persistently, but
  3474 older versions of Isabelle will fail to start up if a negative prems
  3475 limit is imposed.
  3476 
  3477 * Local theory targets may be specified by non-nested blocks of
  3478 ``context/locale/class ... begin'' followed by ``end''.  The body may
  3479 contain definitions, theorems etc., including any derived mechanism
  3480 that has been implemented on top of these primitives.  This concept
  3481 generalizes the existing ``theorem (in ...)'' towards more versatility
  3482 and scalability.
  3483 
  3484 * Proof General interface: proper undo of final 'end' command;
  3485 discontinued Isabelle/classic mode (ML proof scripts).
  3486 
  3487 
  3488 *** Document preparation ***
  3489 
  3490 * Added antiquotation @{theory name} which prints the given name,
  3491 after checking that it refers to a valid ancestor theory in the
  3492 current context.
  3493 
  3494 * Added antiquotations @{ML_type text} and @{ML_struct text} which
  3495 check the given source text as ML type/structure, printing verbatim.
  3496 
  3497 * Added antiquotation @{abbrev "c args"} which prints the abbreviation
  3498 "c args == rhs" given in the current context.  (Any number of
  3499 arguments may be given on the LHS.)
  3500 
  3501 
  3502 *** Pure ***
  3503 
  3504 * The 'class' package offers a combination of axclass and locale to
  3505 achieve Haskell-like type classes in Isabelle.  Definitions and
  3506 theorems within a class context produce both relative results (with
  3507 implicit parameters according to the locale context), and polymorphic
  3508 constants with qualified polymorphism (according to the class
  3509 context).  Within the body context of a 'class' target, a separate
  3510 syntax layer ("user space type system") takes care of converting
  3511 between global polymorphic consts and internal locale representation.
  3512 See src/HOL/ex/Classpackage.thy for examples (as well as main HOL).
  3513 "isatool doc classes" provides a tutorial.
  3514 
  3515 * Generic code generator framework allows to generate executable
  3516 code for ML and Haskell (including Isabelle classes).  A short usage
  3517 sketch:
  3518 
  3519     internal compilation:
  3520         export_code <list of constants (term syntax)> in SML
  3521     writing SML code to a file:
  3522         export_code <list of constants (term syntax)> in SML <filename>
  3523     writing OCaml code to a file:
  3524         export_code <list of constants (term syntax)> in OCaml <filename>
  3525     writing Haskell code to a bunch of files:
  3526         export_code <list of constants (term syntax)> in Haskell <filename>
  3527 
  3528     evaluating closed propositions to True/False using code generation:
  3529         method ``eval''
  3530 
  3531 Reasonable default setup of framework in HOL.
  3532 
  3533 Theorem attributs for selecting and transforming function equations theorems:
  3534 
  3535     [code fun]:        select a theorem as function equation for a specific constant
  3536     [code fun del]:    deselect a theorem as function equation for a specific constant
  3537     [code inline]:     select an equation theorem for unfolding (inlining) in place
  3538     [code inline del]: deselect an equation theorem for unfolding (inlining) in place
  3539 
  3540 User-defined serializations (target in {SML, OCaml, Haskell}):
  3541 
  3542     code_const <and-list of constants (term syntax)>
  3543       {(target) <and-list of const target syntax>}+
  3544 
  3545     code_type <and-list of type constructors>
  3546       {(target) <and-list of type target syntax>}+
  3547 
  3548     code_instance <and-list of instances>
  3549       {(target)}+
  3550         where instance ::= <type constructor> :: <class>
  3551 
  3552     code_class <and_list of classes>
  3553       {(target) <and-list of class target syntax>}+
  3554         where class target syntax ::= <class name> {where {<classop> == <target syntax>}+}?
  3555 
  3556 code_instance and code_class only are effective to target Haskell.
  3557 
  3558 For example usage see src/HOL/ex/Codegenerator.thy and
  3559 src/HOL/ex/Codegenerator_Pretty.thy.  A separate tutorial on code
  3560 generation from Isabelle/HOL theories is available via "isatool doc
  3561 codegen".
  3562 
  3563 * Code generator: consts in 'consts_code' Isar commands are now
  3564 referred to by usual term syntax (including optional type
  3565 annotations).
  3566 
  3567 * Command 'no_translations' removes translation rules from theory
  3568 syntax.
  3569 
  3570 * Overloaded definitions are now actually checked for acyclic
  3571 dependencies.  The overloading scheme is slightly more general than
  3572 that of Haskell98, although Isabelle does not demand an exact
  3573 correspondence to type class and instance declarations.
  3574 INCOMPATIBILITY, use ``defs (unchecked overloaded)'' to admit more
  3575 exotic versions of overloading -- at the discretion of the user!
  3576 
  3577 Polymorphic constants are represented via type arguments, i.e. the
  3578 instantiation that matches an instance against the most general
  3579 declaration given in the signature.  For example, with the declaration
  3580 c :: 'a => 'a => 'a, an instance c :: nat => nat => nat is represented
  3581 as c(nat).  Overloading is essentially simultaneous structural
  3582 recursion over such type arguments.  Incomplete specification patterns
  3583 impose global constraints on all occurrences, e.g. c('a * 'a) on the
  3584 LHS means that more general c('a * 'b) will be disallowed on any RHS.
  3585 Command 'print_theory' outputs the normalized system of recursive
  3586 equations, see section "definitions".
  3587 
  3588 * Configuration options are maintained within the theory or proof
  3589 context (with name and type bool/int/string), providing a very simple
  3590 interface to a poor-man's version of general context data.  Tools may
  3591 declare options in ML (e.g. using Attrib.config_int) and then refer to
  3592 these values using Config.get etc.  Users may change options via an
  3593 associated attribute of the same name.  This form of context
  3594 declaration works particularly well with commands 'declare' or
  3595 'using', for example ``declare [[foo = 42]]''.  Thus it has become
  3596 very easy to avoid global references, which would not observe Isar
  3597 toplevel undo/redo and fail to work with multithreading.
  3598 
  3599 Various global ML references of Pure and HOL have been turned into
  3600 configuration options:
  3601 
  3602   Unify.search_bound		unify_search_bound
  3603   Unify.trace_bound		unify_trace_bound
  3604   Unify.trace_simp		unify_trace_simp
  3605   Unify.trace_types		unify_trace_types
  3606   Simplifier.simp_depth_limit	simp_depth_limit
  3607   Blast.depth_limit		blast_depth_limit
  3608   DatatypeProp.dtK		datatype_distinctness_limit
  3609   fast_arith_neq_limit  	fast_arith_neq_limit
  3610   fast_arith_split_limit	fast_arith_split_limit
  3611 
  3612 * Named collections of theorems may be easily installed as context
  3613 data using the functor NamedThmsFun (see also
  3614 src/Pure/Tools/named_thms.ML).  The user may add or delete facts via
  3615 attributes; there is also a toplevel print command.  This facility is
  3616 just a common case of general context data, which is the preferred way
  3617 for anything more complex than just a list of facts in canonical
  3618 order.
  3619 
  3620 * Isar: command 'declaration' augments a local theory by generic
  3621 declaration functions written in ML.  This enables arbitrary content
  3622 being added to the context, depending on a morphism that tells the
  3623 difference of the original declaration context wrt. the application
  3624 context encountered later on.
  3625 
  3626 * Isar: proper interfaces for simplification procedures.  Command
  3627 'simproc_setup' declares named simprocs (with match patterns, and body
  3628 text in ML).  Attribute "simproc" adds/deletes simprocs in the current
  3629 context.  ML antiquotation @{simproc name} retrieves named simprocs.
  3630 
  3631 * Isar: an extra pair of brackets around attribute declarations
  3632 abbreviates a theorem reference involving an internal dummy fact,
  3633 which will be ignored later --- only the effect of the attribute on
  3634 the background context will persist.  This form of in-place
  3635 declarations is particularly useful with commands like 'declare' and
  3636 'using', for example ``have A using [[simproc a]] by simp''.
  3637 
  3638 * Isar: method "assumption" (and implicit closing of subproofs) now
  3639 takes simple non-atomic goal assumptions into account: after applying
  3640 an assumption as a rule the resulting subgoals are solved by atomic
  3641 assumption steps.  This is particularly useful to finish 'obtain'
  3642 goals, such as "!!x. (!!x. P x ==> thesis) ==> P x ==> thesis",
  3643 without referring to the original premise "!!x. P x ==> thesis" in the
  3644 Isar proof context.  POTENTIAL INCOMPATIBILITY: method "assumption" is
  3645 more permissive.
  3646 
  3647 * Isar: implicit use of prems from the Isar proof context is
  3648 considered a legacy feature.  Common applications like ``have A .''
  3649 may be replaced by ``have A by fact'' or ``note `A`''.  In general,
  3650 referencing facts explicitly here improves readability and
  3651 maintainability of proof texts.
  3652 
  3653 * Isar: improper proof element 'guess' is like 'obtain', but derives
  3654 the obtained context from the course of reasoning!  For example:
  3655 
  3656   assume "EX x y. A x & B y"   -- "any previous fact"
  3657   then guess x and y by clarify
  3658 
  3659 This technique is potentially adventurous, depending on the facts and
  3660 proof tools being involved here.
  3661 
  3662 * Isar: known facts from the proof context may be specified as literal
  3663 propositions, using ASCII back-quote syntax.  This works wherever
  3664 named facts used to be allowed so far, in proof commands, proof
  3665 methods, attributes etc.  Literal facts are retrieved from the context
  3666 according to unification of type and term parameters.  For example,
  3667 provided that "A" and "A ==> B" and "!!x. P x ==> Q x" are known
  3668 theorems in the current context, then these are valid literal facts:
  3669 `A` and `A ==> B` and `!!x. P x ==> Q x" as well as `P a ==> Q a` etc.
  3670 
  3671 There is also a proof method "fact" which does the same composition
  3672 for explicit goal states, e.g. the following proof texts coincide with
  3673 certain special cases of literal facts:
  3674 
  3675   have "A" by fact                 ==  note `A`
  3676   have "A ==> B" by fact           ==  note `A ==> B`
  3677   have "!!x. P x ==> Q x" by fact  ==  note `!!x. P x ==> Q x`
  3678   have "P a ==> Q a" by fact       ==  note `P a ==> Q a`
  3679 
  3680 * Isar: ":" (colon) is no longer a symbolic identifier character in
  3681 outer syntax.  Thus symbolic identifiers may be used without
  3682 additional white space in declarations like this: ``assume *: A''.
  3683 
  3684 * Isar: 'print_facts' prints all local facts of the current context,
  3685 both named and unnamed ones.
  3686 
  3687 * Isar: 'def' now admits simultaneous definitions, e.g.:
  3688 
  3689   def x == "t" and y == "u"
  3690 
  3691 * Isar: added command 'unfolding', which is structurally similar to
  3692 'using', but affects both the goal state and facts by unfolding given
  3693 rewrite rules.  Thus many occurrences of the 'unfold' method or
  3694 'unfolded' attribute may be replaced by first-class proof text.
  3695 
  3696 * Isar: methods 'unfold' / 'fold', attributes 'unfolded' / 'folded',
  3697 and command 'unfolding' now all support object-level equalities
  3698 (potentially conditional).  The underlying notion of rewrite rule is
  3699 analogous to the 'rule_format' attribute, but *not* that of the
  3700 Simplifier (which is usually more generous).
  3701 
  3702 * Isar: the new attribute [rotated n] (default n = 1) rotates the
  3703 premises of a theorem by n. Useful in conjunction with drule.
  3704 
  3705 * Isar: the goal restriction operator [N] (default N = 1) evaluates a
  3706 method expression within a sandbox consisting of the first N
  3707 sub-goals, which need to exist.  For example, ``simp_all [3]''
  3708 simplifies the first three sub-goals, while (rule foo, simp_all)[]
  3709 simplifies all new goals that emerge from applying rule foo to the
  3710 originally first one.
  3711 
  3712 * Isar: schematic goals are no longer restricted to higher-order
  3713 patterns; e.g. ``lemma "?P(?x)" by (rule TrueI)'' now works as
  3714 expected.
  3715 
  3716 * Isar: the conclusion of a long theorem statement is now either
  3717 'shows' (a simultaneous conjunction, as before), or 'obtains'
  3718 (essentially a disjunction of cases with local parameters and
  3719 assumptions).  The latter allows to express general elimination rules
  3720 adequately; in this notation common elimination rules look like this:
  3721 
  3722   lemma exE:    -- "EX x. P x ==> (!!x. P x ==> thesis) ==> thesis"
  3723     assumes "EX x. P x"
  3724     obtains x where "P x"
  3725 
  3726   lemma conjE:  -- "A & B ==> (A ==> B ==> thesis) ==> thesis"
  3727     assumes "A & B"
  3728     obtains A and B
  3729 
  3730   lemma disjE:  -- "A | B ==> (A ==> thesis) ==> (B ==> thesis) ==> thesis"
  3731     assumes "A | B"
  3732     obtains
  3733       A
  3734     | B
  3735 
  3736 The subsequent classical rules even refer to the formal "thesis"
  3737 explicitly:
  3738 
  3739   lemma classical:     -- "(~ thesis ==> thesis) ==> thesis"
  3740     obtains "~ thesis"
  3741 
  3742   lemma Peirce's_Law:  -- "((thesis ==> something) ==> thesis) ==> thesis"
  3743     obtains "thesis ==> something"
  3744 
  3745 The actual proof of an 'obtains' statement is analogous to that of the
  3746 Isar proof element 'obtain', only that there may be several cases.
  3747 Optional case names may be specified in parentheses; these will be
  3748 available both in the present proof and as annotations in the
  3749 resulting rule, for later use with the 'cases' method (cf. attribute
  3750 case_names).
  3751 
  3752 * Isar: the assumptions of a long theorem statement are available as
  3753 "assms" fact in the proof context.  This is more appropriate than the
  3754 (historical) "prems", which refers to all assumptions of the current
  3755 context, including those from the target locale, proof body etc.
  3756 
  3757 * Isar: 'print_statement' prints theorems from the current theory or
  3758 proof context in long statement form, according to the syntax of a
  3759 top-level lemma.
  3760 
  3761 * Isar: 'obtain' takes an optional case name for the local context
  3762 introduction rule (default "that").
  3763 
  3764 * Isar: removed obsolete 'concl is' patterns.  INCOMPATIBILITY, use
  3765 explicit (is "_ ==> ?foo") in the rare cases where this still happens
  3766 to occur.
  3767 
  3768 * Pure: syntax "CONST name" produces a fully internalized constant
  3769 according to the current context.  This is particularly useful for
  3770 syntax translations that should refer to internal constant
  3771 representations independently of name spaces.
  3772 
  3773 * Pure: syntax constant for foo (binder "FOO ") is called "foo_binder"
  3774 instead of "FOO ". This allows multiple binder declarations to coexist
  3775 in the same context.  INCOMPATIBILITY.
  3776 
  3777 * Isar/locales: 'notation' provides a robust interface to the 'syntax'
  3778 primitive that also works in a locale context (both for constants and
  3779 fixed variables). Type declaration and internal syntactic representation
  3780 of given constants retrieved from the context. Likewise, the
  3781 'no_notation' command allows to remove given syntax annotations from the
  3782 current context.
  3783 
  3784 * Isar/locales: new derived specification elements 'axiomatization',
  3785 'definition', 'abbreviation', which support type-inference, admit
  3786 object-level specifications (equality, equivalence).  See also the
  3787 isar-ref manual.  Examples:
  3788 
  3789   axiomatization
  3790     eq  (infix "===" 50) where
  3791     eq_refl: "x === x" and eq_subst: "x === y ==> P x ==> P y"
  3792 
  3793   definition "f x y = x + y + 1"
  3794   definition g where "g x = f x x"
  3795 
  3796   abbreviation
  3797     neq  (infix "=!=" 50) where
  3798     "x =!= y == ~ (x === y)"
  3799 
  3800 These specifications may be also used in a locale context.  Then the
  3801 constants being introduced depend on certain fixed parameters, and the
  3802 constant name is qualified by the locale base name.  An internal
  3803 abbreviation takes care for convenient input and output, making the
  3804 parameters implicit and using the original short name.  See also
  3805 src/HOL/ex/Abstract_NAT.thy for an example of deriving polymorphic
  3806 entities from a monomorphic theory.
  3807 
  3808 Presently, abbreviations are only available 'in' a target locale, but
  3809 not inherited by general import expressions.  Also note that
  3810 'abbreviation' may be used as a type-safe replacement for 'syntax' +
  3811 'translations' in common applications.  The "no_abbrevs" print mode
  3812 prevents folding of abbreviations in term output.
  3813 
  3814 Concrete syntax is attached to specified constants in internal form,
  3815 independently of name spaces.  The parse tree representation is
  3816 slightly different -- use 'notation' instead of raw 'syntax', and
  3817 'translations' with explicit "CONST" markup to accommodate this.
  3818 
  3819 * Pure/Isar: unified syntax for new-style specification mechanisms
  3820 (e.g.  'definition', 'abbreviation', or 'inductive' in HOL) admits
  3821 full type inference and dummy patterns ("_").  For example:
  3822 
  3823   definition "K x _ = x"
  3824 
  3825   inductive conj for A B
  3826   where "A ==> B ==> conj A B"
  3827 
  3828 * Pure: command 'print_abbrevs' prints all constant abbreviations of
  3829 the current context.  Print mode "no_abbrevs" prevents inversion of
  3830 abbreviations on output.
  3831 
  3832 * Isar/locales: improved parameter handling: use of locales "var" and
  3833 "struct" no longer necessary; - parameter renamings are no longer
  3834 required to be injective.  For example, this allows to define
  3835 endomorphisms as locale endom = homom mult mult h.
  3836 
  3837 * Isar/locales: changed the way locales with predicates are defined.
  3838 Instead of accumulating the specification, the imported expression is
  3839 now an interpretation.  INCOMPATIBILITY: different normal form of
  3840 locale expressions.  In particular, in interpretations of locales with
  3841 predicates, goals repesenting already interpreted fragments are not
  3842 removed automatically.  Use methods `intro_locales' and
  3843 `unfold_locales'; see below.
  3844 
  3845 * Isar/locales: new methods `intro_locales' and `unfold_locales'
  3846 provide backward reasoning on locales predicates.  The methods are
  3847 aware of interpretations and discharge corresponding goals.
  3848 `intro_locales' is less aggressive then `unfold_locales' and does not
  3849 unfold predicates to assumptions.
  3850 
  3851 * Isar/locales: the order in which locale fragments are accumulated
  3852 has changed.  This enables to override declarations from fragments due
  3853 to interpretations -- for example, unwanted simp rules.
  3854 
  3855 * Isar/locales: interpretation in theories and proof contexts has been
  3856 extended.  One may now specify (and prove) equations, which are
  3857 unfolded in interpreted theorems.  This is useful for replacing
  3858 defined concepts (constants depending on locale parameters) by
  3859 concepts already existing in the target context.  Example:
  3860 
  3861   interpretation partial_order ["op <= :: [int, int] => bool"]
  3862     where "partial_order.less (op <=) (x::int) y = (x < y)"
  3863 
  3864 Typically, the constant `partial_order.less' is created by a
  3865 definition specification element in the context of locale
  3866 partial_order.
  3867 
  3868 * Method "induct": improved internal context management to support
  3869 local fixes and defines on-the-fly. Thus explicit meta-level
  3870 connectives !!  and ==> are rarely required anymore in inductive goals
  3871 (using object-logic connectives for this purpose has been long
  3872 obsolete anyway). Common proof patterns are explained in
  3873 src/HOL/Induct/Common_Patterns.thy, see also
  3874 src/HOL/Isar_examples/Puzzle.thy and src/HOL/Lambda for realistic
  3875 examples.
  3876 
  3877 * Method "induct": improved handling of simultaneous goals. Instead of
  3878 introducing object-level conjunction, the statement is now split into
  3879 several conclusions, while the corresponding symbolic cases are nested
  3880 accordingly. INCOMPATIBILITY, proofs need to be structured explicitly,
  3881 see src/HOL/Induct/Common_Patterns.thy, for example.
  3882 
  3883 * Method "induct": mutual induction rules are now specified as a list
  3884 of rule sharing the same induction cases. HOL packages usually provide
  3885 foo_bar.inducts for mutually defined items foo and bar (e.g. inductive
  3886 predicates/sets or datatypes). INCOMPATIBILITY, users need to specify
  3887 mutual induction rules differently, i.e. like this:
  3888 
  3889   (induct rule: foo_bar.inducts)
  3890   (induct set: foo bar)
  3891   (induct pred: foo bar)
  3892   (induct type: foo bar)
  3893 
  3894 The ML function ProjectRule.projections turns old-style rules into the
  3895 new format.
  3896 
  3897 * Method "coinduct": dual of induction, see
  3898 src/HOL/Library/Coinductive_List.thy for various examples.
  3899 
  3900 * Method "cases", "induct", "coinduct": the ``(open)'' option is
  3901 considered a legacy feature.
  3902 
  3903 * Attribute "symmetric" produces result with standardized schematic
  3904 variables (index 0).  Potential INCOMPATIBILITY.
  3905 
  3906 * Simplifier: by default the simplifier trace only shows top level
  3907 rewrites now. That is, trace_simp_depth_limit is set to 1 by
  3908 default. Thus there is less danger of being flooded by the trace. The
  3909 trace indicates where parts have been suppressed.
  3910   
  3911 * Provers/classical: removed obsolete classical version of elim_format
  3912 attribute; classical elim/dest rules are now treated uniformly when
  3913 manipulating the claset.
  3914 
  3915 * Provers/classical: stricter checks to ensure that supplied intro,
  3916 dest and elim rules are well-formed; dest and elim rules must have at
  3917 least one premise.
  3918 
  3919 * Provers/classical: attributes dest/elim/intro take an optional
  3920 weight argument for the rule (just as the Pure versions).  Weights are
  3921 ignored by automated tools, but determine the search order of single
  3922 rule steps.
  3923 
  3924 * Syntax: input syntax now supports dummy variable binding "%_. b",
  3925 where the body does not mention the bound variable.  Note that dummy
  3926 patterns implicitly depend on their context of bounds, which makes
  3927 "{_. _}" match any set comprehension as expected.  Potential
  3928 INCOMPATIBILITY -- parse translations need to cope with syntactic
  3929 constant "_idtdummy" in the binding position.
  3930 
  3931 * Syntax: removed obsolete syntactic constant "_K" and its associated
  3932 parse translation.  INCOMPATIBILITY -- use dummy abstraction instead,
  3933 for example "A -> B" => "Pi A (%_. B)".
  3934 
  3935 * Pure: 'class_deps' command visualizes the subclass relation, using
  3936 the graph browser tool.
  3937 
  3938 * Pure: 'print_theory' now suppresses certain internal declarations by
  3939 default; use '!' option for full details.
  3940 
  3941 
  3942 *** HOL ***
  3943 
  3944 * Method "metis" proves goals by applying the Metis general-purpose
  3945 resolution prover (see also http://gilith.com/software/metis/).
  3946 Examples are in the directory MetisExamples.  WARNING: the
  3947 Isabelle/HOL-Metis integration does not yet work properly with
  3948 multi-threading.
  3949   
  3950 * Command 'sledgehammer' invokes external automatic theorem provers as
  3951 background processes.  It generates calls to the "metis" method if
  3952 successful. These can be pasted into the proof.  Users do not have to
  3953 wait for the automatic provers to return.  WARNING: does not really
  3954 work with multi-threading.
  3955 
  3956 * New "auto_quickcheck" feature tests outermost goal statements for
  3957 potential counter-examples.  Controlled by ML references
  3958 auto_quickcheck (default true) and auto_quickcheck_time_limit (default
  3959 5000 milliseconds).  Fails silently if statements is outside of
  3960 executable fragment, or any other codgenerator problem occurs.
  3961 
  3962 * New constant "undefined" with axiom "undefined x = undefined".
  3963 
  3964 * Added class "HOL.eq", allowing for code generation with polymorphic
  3965 equality.
  3966 
  3967 * Some renaming of class constants due to canonical name prefixing in
  3968 the new 'class' package:
  3969 
  3970     HOL.abs ~> HOL.abs_class.abs
  3971     HOL.divide ~> HOL.divide_class.divide
  3972     0 ~> HOL.zero_class.zero
  3973     1 ~> HOL.one_class.one
  3974     op + ~> HOL.plus_class.plus
  3975     op - ~> HOL.minus_class.minus
  3976     uminus ~> HOL.minus_class.uminus
  3977     op * ~> HOL.times_class.times
  3978     op < ~> HOL.ord_class.less
  3979     op <= > HOL.ord_class.less_eq
  3980     Nat.power ~> Power.power_class.power
  3981     Nat.size ~> Nat.size_class.size
  3982     Numeral.number_of ~> Numeral.number_class.number_of
  3983     FixedPoint.Inf ~> Lattices.complete_lattice_class.Inf
  3984     FixedPoint.Sup ~> Lattices.complete_lattice_class.Sup
  3985     Orderings.min ~> Orderings.ord_class.min
  3986     Orderings.max ~> Orderings.ord_class.max
  3987     Divides.op div ~> Divides.div_class.div
  3988     Divides.op mod ~> Divides.div_class.mod
  3989     Divides.op dvd ~> Divides.div_class.dvd
  3990 
  3991 INCOMPATIBILITY.  Adaptions may be required in the following cases:
  3992 
  3993 a) User-defined constants using any of the names "plus", "minus",
  3994 "times", "less" or "less_eq". The standard syntax translations for
  3995 "+", "-" and "*" may go wrong.  INCOMPATIBILITY: use more specific
  3996 names.
  3997 
  3998 b) Variables named "plus", "minus", "times", "less", "less_eq"
  3999 INCOMPATIBILITY: use more specific names.
  4000 
  4001 c) Permutative equations (e.g. "a + b = b + a")
  4002 Since the change of names also changes the order of terms, permutative
  4003 rewrite rules may get applied in a different order. Experience shows
  4004 that this is rarely the case (only two adaptions in the whole Isabelle
  4005 distribution).  INCOMPATIBILITY: rewrite proofs
  4006 
  4007 d) ML code directly refering to constant names
  4008 This in general only affects hand-written proof tactics, simprocs and
  4009 so on.  INCOMPATIBILITY: grep your sourcecode and replace names.
  4010 Consider using @{const_name} antiquotation.
  4011 
  4012 * New class "default" with associated constant "default".
  4013 
  4014 * Function "sgn" is now overloaded and available on int, real, complex
  4015 (and other numeric types), using class "sgn".  Two possible defs of
  4016 sgn are given as equational assumptions in the classes sgn_if and
  4017 sgn_div_norm; ordered_idom now also inherits from sgn_if.
  4018 INCOMPATIBILITY.
  4019 
  4020 * Locale "partial_order" now unified with class "order" (cf. theory
  4021 Orderings), added parameter "less".  INCOMPATIBILITY.
  4022 
  4023 * Renamings in classes "order" and "linorder": facts "refl", "trans" and
  4024 "cases" to "order_refl", "order_trans" and "linorder_cases", to avoid
  4025 clashes with HOL "refl" and "trans".  INCOMPATIBILITY.
  4026 
  4027 * Classes "order" and "linorder": potential INCOMPATIBILITY due to
  4028 changed order of proof goals in instance proofs.
  4029 
  4030 * The transitivity reasoner for partial and linear orders is set up
  4031 for classes "order" and "linorder".  Instances of the reasoner are available
  4032 in all contexts importing or interpreting the corresponding locales.
  4033 Method "order" invokes the reasoner separately; the reasoner
  4034 is also integrated with the Simplifier as a solver.  Diagnostic
  4035 command 'print_orders' shows the available instances of the reasoner
  4036 in the current context.
  4037 
  4038 * Localized monotonicity predicate in theory "Orderings"; integrated
  4039 lemmas max_of_mono and min_of_mono with this predicate.
  4040 INCOMPATIBILITY.
  4041 
  4042 * Formulation of theorem "dense" changed slightly due to integration
  4043 with new class dense_linear_order.
  4044 
  4045 * Uniform lattice theory development in HOL.
  4046 
  4047     constants "meet" and "join" now named "inf" and "sup"
  4048     constant "Meet" now named "Inf"
  4049 
  4050     classes "meet_semilorder" and "join_semilorder" now named
  4051       "lower_semilattice" and "upper_semilattice"
  4052     class "lorder" now named "lattice"
  4053     class "comp_lat" now named "complete_lattice"
  4054 
  4055     Instantiation of lattice classes allows explicit definitions
  4056     for "inf" and "sup" operations (or "Inf" and "Sup" for complete lattices).
  4057 
  4058   INCOMPATIBILITY.  Theorem renames:
  4059 
  4060     meet_left_le            ~> inf_le1
  4061     meet_right_le           ~> inf_le2
  4062     join_left_le            ~> sup_ge1
  4063     join_right_le           ~> sup_ge2
  4064     meet_join_le            ~> inf_sup_ord
  4065     le_meetI                ~> le_infI
  4066     join_leI                ~> le_supI
  4067     le_meet                 ~> le_inf_iff
  4068     le_join                 ~> ge_sup_conv
  4069     meet_idempotent         ~> inf_idem
  4070     join_idempotent         ~> sup_idem
  4071     meet_comm               ~> inf_commute
  4072     join_comm               ~> sup_commute
  4073     meet_leI1               ~> le_infI1
  4074     meet_leI2               ~> le_infI2
  4075     le_joinI1               ~> le_supI1
  4076     le_joinI2               ~> le_supI2
  4077     meet_assoc              ~> inf_assoc
  4078     join_assoc              ~> sup_assoc
  4079     meet_left_comm          ~> inf_left_commute
  4080     meet_left_idempotent    ~> inf_left_idem
  4081     join_left_comm          ~> sup_left_commute
  4082     join_left_idempotent    ~> sup_left_idem
  4083     meet_aci                ~> inf_aci
  4084     join_aci                ~> sup_aci
  4085     le_def_meet             ~> le_iff_inf
  4086     le_def_join             ~> le_iff_sup
  4087     join_absorp2            ~> sup_absorb2
  4088     join_absorp1            ~> sup_absorb1
  4089     meet_absorp1            ~> inf_absorb1
  4090     meet_absorp2            ~> inf_absorb2
  4091     meet_join_absorp        ~> inf_sup_absorb
  4092     join_meet_absorp        ~> sup_inf_absorb
  4093     distrib_join_le         ~> distrib_sup_le
  4094     distrib_meet_le         ~> distrib_inf_le
  4095 
  4096     add_meet_distrib_left   ~> add_inf_distrib_left
  4097     add_join_distrib_left   ~> add_sup_distrib_left
  4098     is_join_neg_meet        ~> is_join_neg_inf
  4099     is_meet_neg_join        ~> is_meet_neg_sup
  4100     add_meet_distrib_right  ~> add_inf_distrib_right
  4101     add_join_distrib_right  ~> add_sup_distrib_right
  4102     add_meet_join_distribs  ~> add_sup_inf_distribs
  4103     join_eq_neg_meet        ~> sup_eq_neg_inf
  4104     meet_eq_neg_join        ~> inf_eq_neg_sup
  4105     add_eq_meet_join        ~> add_eq_inf_sup
  4106     meet_0_imp_0            ~> inf_0_imp_0
  4107     join_0_imp_0            ~> sup_0_imp_0
  4108     meet_0_eq_0             ~> inf_0_eq_0
  4109     join_0_eq_0             ~> sup_0_eq_0
  4110     neg_meet_eq_join        ~> neg_inf_eq_sup
  4111     neg_join_eq_meet        ~> neg_sup_eq_inf
  4112     join_eq_if              ~> sup_eq_if
  4113 
  4114     mono_meet               ~> mono_inf
  4115     mono_join               ~> mono_sup
  4116     meet_bool_eq            ~> inf_bool_eq
  4117     join_bool_eq            ~> sup_bool_eq
  4118     meet_fun_eq             ~> inf_fun_eq
  4119     join_fun_eq             ~> sup_fun_eq
  4120     meet_set_eq             ~> inf_set_eq
  4121     join_set_eq             ~> sup_set_eq
  4122     meet1_iff               ~> inf1_iff
  4123     meet2_iff               ~> inf2_iff
  4124     meet1I                  ~> inf1I
  4125     meet2I                  ~> inf2I
  4126     meet1D1                 ~> inf1D1
  4127     meet2D1                 ~> inf2D1
  4128     meet1D2                 ~> inf1D2
  4129     meet2D2                 ~> inf2D2
  4130     meet1E                  ~> inf1E
  4131     meet2E                  ~> inf2E
  4132     join1_iff               ~> sup1_iff
  4133     join2_iff               ~> sup2_iff
  4134     join1I1                 ~> sup1I1
  4135     join2I1                 ~> sup2I1
  4136     join1I1                 ~> sup1I1
  4137     join2I2                 ~> sup1I2
  4138     join1CI                 ~> sup1CI
  4139     join2CI                 ~> sup2CI
  4140     join1E                  ~> sup1E
  4141     join2E                  ~> sup2E
  4142 
  4143     is_meet_Meet            ~> is_meet_Inf
  4144     Meet_bool_def           ~> Inf_bool_def
  4145     Meet_fun_def            ~> Inf_fun_def
  4146     Meet_greatest           ~> Inf_greatest
  4147     Meet_lower              ~> Inf_lower
  4148     Meet_set_def            ~> Inf_set_def
  4149 
  4150     Sup_def                 ~> Sup_Inf
  4151     Sup_bool_eq             ~> Sup_bool_def
  4152     Sup_fun_eq              ~> Sup_fun_def
  4153     Sup_set_eq              ~> Sup_set_def
  4154 
  4155     listsp_meetI            ~> listsp_infI
  4156     listsp_meet_eq          ~> listsp_inf_eq
  4157 
  4158     meet_min                ~> inf_min
  4159     join_max                ~> sup_max
  4160 
  4161 * Added syntactic class "size"; overloaded constant "size" now has
  4162 type "'a::size ==> bool"
  4163 
  4164 * Internal reorganisation of `size' of datatypes: size theorems
  4165 "foo.size" are no longer subsumed by "foo.simps" (but are still
  4166 simplification rules by default!); theorems "prod.size" now named
  4167 "*.size".
  4168 
  4169 * Class "div" now inherits from class "times" rather than "type".
  4170 INCOMPATIBILITY.
  4171 
  4172 * HOL/Finite_Set: "name-space" locales Lattice, Distrib_lattice,
  4173 Linorder etc.  have disappeared; operations defined in terms of
  4174 fold_set now are named Inf_fin, Sup_fin.  INCOMPATIBILITY.
  4175 
  4176 * HOL/Nat: neq0_conv no longer declared as iff.  INCOMPATIBILITY.
  4177 
  4178 * HOL-Word: New extensive library and type for generic, fixed size
  4179 machine words, with arithemtic, bit-wise, shifting and rotating
  4180 operations, reflection into int, nat, and bool lists, automation for
  4181 linear arithmetic (by automatic reflection into nat or int), including
  4182 lemmas on overflow and monotonicity.  Instantiated to all appropriate
  4183 arithmetic type classes, supporting automatic simplification of
  4184 numerals on all operations.
  4185 
  4186 * Library/Boolean_Algebra: locales for abstract boolean algebras.
  4187 
  4188 * Library/Numeral_Type: numbers as types, e.g. TYPE(32).
  4189 
  4190 * Code generator library theories:
  4191   - Code_Integer represents HOL integers by big integer literals in target
  4192     languages.
  4193   - Code_Char represents HOL characters by character literals in target
  4194     languages.
  4195   - Code_Char_chr like Code_Char, but also offers treatment of character
  4196     codes; includes Code_Integer.
  4197   - Executable_Set allows to generate code for finite sets using lists.
  4198   - Executable_Rat implements rational numbers as triples (sign, enumerator,
  4199     denominator).
  4200   - Executable_Real implements a subset of real numbers, namly those
  4201     representable by rational numbers.
  4202   - Efficient_Nat implements natural numbers by integers, which in general will
  4203     result in higher efficency; pattern matching with 0/Suc is eliminated;
  4204     includes Code_Integer.
  4205   - Code_Index provides an additional datatype index which is mapped to
  4206     target-language built-in integers.
  4207   - Code_Message provides an additional datatype message_string which is isomorphic to
  4208     strings; messages are mapped to target-language strings.
  4209 
  4210 * New package for inductive predicates
  4211 
  4212   An n-ary predicate p with m parameters z_1, ..., z_m can now be defined via
  4213 
  4214     inductive
  4215       p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4216       for z_1 :: U_1 and ... and z_n :: U_m
  4217     where
  4218       rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4219     | ...
  4220 
  4221   with full support for type-inference, rather than
  4222 
  4223     consts s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4224 
  4225     abbreviation p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4226     where "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4227 
  4228     inductive "s z_1 ... z_m"
  4229     intros
  4230       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4231       ...
  4232 
  4233   For backward compatibility, there is a wrapper allowing inductive
  4234   sets to be defined with the new package via
  4235 
  4236     inductive_set
  4237       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4238       for z_1 :: U_1 and ... and z_n :: U_m
  4239     where
  4240       rule_1: "... ==> (t_1_1, ..., t_1_n) : s z_1 ... z_m"
  4241     | ...
  4242 
  4243   or
  4244 
  4245     inductive_set
  4246       s :: "U_1 => ... => U_m => (T_1 * ... * T_n) set"
  4247       and p :: "U_1 => ... => U_m => T_1 => ... => T_n => bool"
  4248       for z_1 :: U_1 and ... and z_n :: U_m
  4249     where
  4250       "p z_1 ... z_m x_1 ... x_n == (x_1, ..., x_n) : s z_1 ... z_m"
  4251     | rule_1: "... ==> p z_1 ... z_m t_1_1 ... t_1_n"
  4252     | ...
  4253 
  4254   if the additional syntax "p ..." is required.
  4255 
  4256   Numerous examples can be found in the subdirectories src/HOL/Auth,
  4257   src/HOL/Bali, src/HOL/Induct, and src/HOL/MicroJava.
  4258 
  4259   INCOMPATIBILITIES:
  4260 
  4261   - Since declaration and definition of inductive sets or predicates
  4262     is no longer separated, abbreviations involving the newly
  4263     introduced sets or predicates must be specified together with the
  4264     introduction rules after the 'where' keyword (see above), rather
  4265     than before the actual inductive definition.
  4266 
  4267   - The variables in induction and elimination rules are now
  4268     quantified in the order of their occurrence in the introduction
  4269     rules, rather than in alphabetical order. Since this may break
  4270     some proofs, these proofs either have to be repaired, e.g. by
  4271     reordering the variables a_i_1 ... a_i_{k_i} in Isar 'case'
  4272     statements of the form
  4273 
  4274       case (rule_i a_i_1 ... a_i_{k_i})
  4275 
  4276     or the old order of quantification has to be restored by explicitly adding
  4277     meta-level quantifiers in the introduction rules, i.e.
  4278 
  4279       | rule_i: "!!a_i_1 ... a_i_{k_i}. ... ==> p z_1 ... z_m t_i_1 ... t_i_n"
  4280 
  4281   - The format of the elimination rules is now
  4282 
  4283       p z_1 ... z_m x_1 ... x_n ==>
  4284         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4285         ==> ... ==> P
  4286 
  4287     for predicates and
  4288 
  4289       (x_1, ..., x_n) : s z_1 ... z_m ==>
  4290         (!!a_1_1 ... a_1_{k_1}. x_1 = t_1_1 ==> ... ==> x_n = t_1_n ==> ... ==> P)
  4291         ==> ... ==> P
  4292 
  4293     for sets rather than
  4294 
  4295       x : s z_1 ... z_m ==>
  4296         (!!a_1_1 ... a_1_{k_1}. x = (t_1_1, ..., t_1_n) ==> ... ==> P)
  4297         ==> ... ==> P
  4298 
  4299     This may require terms in goals to be expanded to n-tuples
  4300     (e.g. using case_tac or simplification with the split_paired_all
  4301     rule) before the above elimination rule is applicable.
  4302 
  4303   - The elimination or case analysis rules for (mutually) inductive
  4304     sets or predicates are now called "p_1.cases" ... "p_k.cases". The
  4305     list of rules "p_1_..._p_k.elims" is no longer available.
  4306 
  4307 * New package "function"/"fun" for general recursive functions,
  4308 supporting mutual and nested recursion, definitions in local contexts,
  4309 more general pattern matching and partiality. See HOL/ex/Fundefs.thy
  4310 for small examples, and the separate tutorial on the function
  4311 package. The old recdef "package" is still available as before, but
  4312 users are encouraged to use the new package.
  4313 
  4314 * Method "lexicographic_order" automatically synthesizes termination
  4315 relations as lexicographic combinations of size measures. 
  4316 
  4317 * Case-expressions allow arbitrary constructor-patterns (including
  4318 "_") and take their order into account, like in functional
  4319 programming.  Internally, this is translated into nested
  4320 case-expressions; missing cases are added and mapped to the predefined
  4321 constant "undefined". In complicated cases printing may no longer show
  4322 the original input but the internal form. Lambda-abstractions allow
  4323 the same form of pattern matching: "% pat1 => e1 | ..." is an
  4324 abbreviation for "%x. case x of pat1 => e1 | ..." where x is a new
  4325 variable.
  4326 
  4327 * IntDef: The constant "int :: nat => int" has been removed; now "int"
  4328 is an abbreviation for "of_nat :: nat => int". The simplification
  4329 rules for "of_nat" have been changed to work like "int" did
  4330 previously.  Potential INCOMPATIBILITY:
  4331   - "of_nat (Suc m)" simplifies to "1 + of_nat m" instead of "of_nat m + 1"
  4332   - of_nat_diff and of_nat_mult are no longer default simp rules
  4333 
  4334 * Method "algebra" solves polynomial equations over (semi)rings using
  4335 Groebner bases. The (semi)ring structure is defined by locales and the
  4336 tool setup depends on that generic context. Installing the method for
  4337 a specific type involves instantiating the locale and possibly adding
  4338 declarations for computation on the coefficients.  The method is
  4339 already instantiated for natural numbers and for the axiomatic class
  4340 of idoms with numerals.  See also the paper by Chaieb and Wenzel at
  4341 CALCULEMUS 2007 for the general principles underlying this
  4342 architecture of context-aware proof-tools.
  4343 
  4344 * Method "ferrack" implements quantifier elimination over
  4345 special-purpose dense linear orders using locales (analogous to
  4346 "algebra"). The method is already installed for class
  4347 {ordered_field,recpower,number_ring} which subsumes real, hyperreal,
  4348 rat, etc.
  4349 
  4350 * Former constant "List.op @" now named "List.append".  Use ML
  4351 antiquotations @{const_name List.append} or @{term " ... @ ... "} to
  4352 circumvent possible incompatibilities when working on ML level.
  4353 
  4354 * primrec: missing cases mapped to "undefined" instead of "arbitrary".
  4355 
  4356 * New function listsum :: 'a list => 'a for arbitrary monoids.
  4357 Special syntax: "SUM x <- xs. f x" (and latex variants)
  4358 
  4359 * New syntax for Haskell-like list comprehension (input only), eg.
  4360 [(x,y). x <- xs, y <- ys, x ~= y], see also src/HOL/List.thy.
  4361 
  4362 * The special syntax for function "filter" has changed from [x :
  4363 xs. P] to [x <- xs. P] to avoid an ambiguity caused by list
  4364 comprehension syntax, and for uniformity.  INCOMPATIBILITY.
  4365 
  4366 * [a..b] is now defined for arbitrary linear orders.  It used to be
  4367 defined on nat only, as an abbreviation for [a..<Suc b]
  4368 INCOMPATIBILITY.
  4369 
  4370 * Renamed lemma "set_take_whileD"  to "set_takeWhileD".
  4371 
  4372 * New functions "sorted" and "sort" in src/HOL/List.thy.
  4373 
  4374 * New lemma collection field_simps (an extension of ring_simps) for
  4375 manipulating (in)equations involving division. Multiplies with all
  4376 denominators that can be proved to be non-zero (in equations) or
  4377 positive/negative (in inequations).
  4378 
  4379 * Lemma collections ring_eq_simps, group_eq_simps and ring_distrib
  4380 have been improved and renamed to ring_simps, group_simps and
  4381 ring_distribs.  Removed lemmas field_xyz in theory Ring_and_Field
  4382 because they were subsumed by lemmas xyz.  INCOMPATIBILITY.
  4383 
  4384 * Theory Library/Commutative_Ring: switched from recdef to function
  4385 package; constants add, mul, pow now curried.  Infix syntax for
  4386 algebraic operations.
  4387 
  4388 * Dropped redundant lemma def_imp_eq in favor of meta_eq_to_obj_eq.
  4389 INCOMPATIBILITY.
  4390 
  4391 * Dropped redundant lemma if_def2 in favor of if_bool_eq_conj.
  4392 INCOMPATIBILITY.
  4393 
  4394 * HOL/records: generalised field-update to take a function on the
  4395 field rather than the new value: r(|A := x|) is translated to A_update
  4396 (K x) r The K-combinator that is internally used is called K_record.
  4397 INCOMPATIBILITY: Usage of the plain update functions has to be
  4398 adapted.
  4399  
  4400 * Class "semiring_0" now contains annihilation axioms x * 0 = 0 and 0
  4401 * x = 0, which are required for a semiring.  Richer structures do not
  4402 inherit from semiring_0 anymore, because this property is a theorem
  4403 there, not an axiom.  INCOMPATIBILITY: In instances of semiring_0,
  4404 there is more to prove, but this is mostly trivial.
  4405 
  4406 * Class "recpower" is generalized to arbitrary monoids, not just
  4407 commutative semirings.  INCOMPATIBILITY: may need to incorporate
  4408 commutativity or semiring properties additionally.
  4409 
  4410 * Constant "List.list_all2" in List.thy now uses authentic syntax.
  4411 INCOMPATIBILITY: translations containing list_all2 may go wrong,
  4412 better use 'abbreviation'.
  4413 
  4414 * Renamed constant "List.op mem" to "List.member".  INCOMPATIBILITY.
  4415 
  4416 * Numeral syntax: type 'bin' which was a mere type copy of 'int' has
  4417 been abandoned in favour of plain 'int'.  INCOMPATIBILITY --
  4418 significant changes for setting up numeral syntax for types:
  4419   - New constants Numeral.pred and Numeral.succ instead
  4420       of former Numeral.bin_pred and Numeral.bin_succ.
  4421   - Use integer operations instead of bin_add, bin_mult and so on.
  4422   - Numeral simplification theorems named Numeral.numeral_simps instead of Bin_simps.
  4423   - ML structure Bin_Simprocs now named Int_Numeral_Base_Simprocs.
  4424 
  4425 See src/HOL/Integ/IntArith.thy for an example setup.
  4426 
  4427 * Command 'normal_form' computes the normal form of a term that may
  4428 contain free variables.  For example ``normal_form "rev [a, b, c]"''
  4429 produces ``[b, c, a]'' (without proof).  This command is suitable for
  4430 heavy-duty computations because the functions are compiled to ML
  4431 first.  Correspondingly, a method "normalization" is provided.  See
  4432 further src/HOL/ex/NormalForm.thy and src/Tools/nbe.ML.
  4433 
  4434 * Alternative iff syntax "A <-> B" for equality on bool (with priority
  4435 25 like -->); output depends on the "iff" print_mode, the default is
  4436 "A = B" (with priority 50).
  4437 
  4438 * Relations less (<) and less_eq (<=) are also available on type bool.
  4439 Modified syntax to disallow nesting without explicit parentheses,
  4440 e.g. "(x < y) < z" or "x < (y < z)", but NOT "x < y < z".  Potential
  4441 INCOMPATIBILITY.
  4442 
  4443 * "LEAST x:A. P" expands to "LEAST x. x:A & P" (input only).
  4444 
  4445 * Relation composition operator "op O" now has precedence 75 and binds
  4446 stronger than union and intersection. INCOMPATIBILITY.
  4447 
  4448 * The old set interval syntax "{m..n(}" (and relatives) has been
  4449 removed.  Use "{m..<n}" (and relatives) instead.
  4450 
  4451 * In the context of the assumption "~(s = t)" the Simplifier rewrites
  4452 "t = s" to False (by simproc "neq").  INCOMPATIBILITY, consider using
  4453 ``declare [[simproc del: neq]]''.
  4454 
  4455 * Simplifier: "m dvd n" where m and n are numbers is evaluated to
  4456 True/False.
  4457 
  4458 * Theorem Cons_eq_map_conv no longer declared as "simp".
  4459 
  4460 * Theorem setsum_mult renamed to setsum_right_distrib.
  4461 
  4462 * Prefer ex1I over ex_ex1I in single-step reasoning, e.g. by the
  4463 ``rule'' method.
  4464 
  4465 * Reimplemented methods "sat" and "satx", with several improvements:
  4466 goals no longer need to be stated as "<prems> ==> False", equivalences
  4467 (i.e. "=" on type bool) are handled, variable names of the form
  4468 "lit_<n>" are no longer reserved, significant speedup.
  4469 
  4470 * Methods "sat" and "satx" can now replay MiniSat proof traces.
  4471 zChaff is still supported as well.
  4472 
  4473 * 'inductive' and 'datatype': provide projections of mutual rules,
  4474 bundled as foo_bar.inducts;
  4475 
  4476 * Library: moved theories Parity, GCD, Binomial, Infinite_Set to
  4477 Library.
  4478 
  4479 * Library: moved theory Accessible_Part to main HOL.
  4480 
  4481 * Library: added theory Coinductive_List of potentially infinite lists
  4482 as greatest fixed-point.
  4483 
  4484 * Library: added theory AssocList which implements (finite) maps as
  4485 association lists.
  4486 
  4487 * Method "evaluation" solves goals (i.e. a boolean expression)
  4488 efficiently by compiling it to ML.  The goal is "proved" (via an
  4489 oracle) if it evaluates to True.
  4490 
  4491 * Linear arithmetic now splits certain operators (e.g. min, max, abs)
  4492 also when invoked by the simplifier.  This results in the Simplifier
  4493 being more powerful on arithmetic goals.  INCOMPATIBILITY.
  4494 Configuration option fast_arith_split_limit=0 recovers the old
  4495 behavior.
  4496 
  4497 * Support for hex (0x20) and binary (0b1001) numerals.
  4498 
  4499 * New method: reify eqs (t), where eqs are equations for an
  4500 interpretation I :: 'a list => 'b => 'c and t::'c is an optional
  4501 parameter, computes a term s::'b and a list xs::'a list and proves the
  4502 theorem I xs s = t. This is also known as reification or quoting. The
  4503 resulting theorem is applied to the subgoal to substitute t with I xs
  4504 s.  If t is omitted, the subgoal itself is reified.
  4505 
  4506 * New method: reflection corr_thm eqs (t). The parameters eqs and (t)
  4507 are as explained above. corr_thm is a theorem for I vs (f t) = I vs t,
  4508 where f is supposed to be a computable function (in the sense of code
  4509 generattion). The method uses reify to compute s and xs as above then
  4510 applies corr_thm and uses normalization by evaluation to "prove" f s =
  4511 r and finally gets the theorem t = r, which is again applied to the
  4512 subgoal. An Example is available in src/HOL/ex/ReflectionEx.thy.
  4513 
  4514 * Reflection: Automatic reification now handels binding, an example is
  4515 available in src/HOL/ex/ReflectionEx.thy
  4516 
  4517 * HOL-Statespace: ``State Spaces: The Locale Way'' introduces a
  4518 command 'statespace' that is similar to 'record', but introduces an
  4519 abstract specification based on the locale infrastructure instead of
  4520 HOL types.  This leads to extra flexibility in composing state spaces,
  4521 in particular multiple inheritance and renaming of components.
  4522 
  4523 
  4524 *** HOL-Complex ***
  4525 
  4526 * Hyperreal: Functions root and sqrt are now defined on negative real
  4527 inputs so that root n (- x) = - root n x and sqrt (- x) = - sqrt x.
  4528 Nonnegativity side conditions have been removed from many lemmas, so
  4529 that more subgoals may now be solved by simplification; potential
  4530 INCOMPATIBILITY.
  4531 
  4532 * Real: new type classes formalize real normed vector spaces and
  4533 algebras, using new overloaded constants scaleR :: real => 'a => 'a
  4534 and norm :: 'a => real.
  4535 
  4536 * Real: constant of_real :: real => 'a::real_algebra_1 injects from
  4537 reals into other types. The overloaded constant Reals :: 'a set is now
  4538 defined as range of_real; potential INCOMPATIBILITY.
  4539 
  4540 * Real: proper support for ML code generation, including 'quickcheck'.
  4541 Reals are implemented as arbitrary precision rationals.
  4542 
  4543 * Hyperreal: Several constants that previously worked only for the
  4544 reals have been generalized, so they now work over arbitrary vector
  4545 spaces. Type annotations may need to be added in some cases; potential
  4546 INCOMPATIBILITY.
  4547 
  4548   Infinitesimal  :: ('a::real_normed_vector) star set
  4549   HFinite        :: ('a::real_normed_vector) star set
  4550   HInfinite      :: ('a::real_normed_vector) star set
  4551   approx         :: ('a::real_normed_vector) star => 'a star => bool
  4552   monad          :: ('a::real_normed_vector) star => 'a star set
  4553   galaxy         :: ('a::real_normed_vector) star => 'a star set
  4554   (NS)LIMSEQ     :: [nat => 'a::real_normed_vector, 'a] => bool
  4555   (NS)convergent :: (nat => 'a::real_normed_vector) => bool
  4556   (NS)Bseq       :: (nat => 'a::real_normed_vector) => bool
  4557   (NS)Cauchy     :: (nat => 'a::real_normed_vector) => bool
  4558   (NS)LIM        :: ['a::real_normed_vector => 'b::real_normed_vector, 'a, 'b] => bool
  4559   is(NS)Cont     :: ['a::real_normed_vector => 'b::real_normed_vector, 'a] => bool
  4560   deriv          :: ['a::real_normed_field => 'a, 'a, 'a] => bool
  4561   sgn            :: 'a::real_normed_vector => 'a
  4562   exp            :: 'a::{recpower,real_normed_field,banach} => 'a
  4563 
  4564 * Complex: Some complex-specific constants are now abbreviations for
  4565 overloaded ones: complex_of_real = of_real, cmod = norm, hcmod =
  4566 hnorm.  Other constants have been entirely removed in favor of the
  4567 polymorphic versions (INCOMPATIBILITY):
  4568 
  4569   approx        <-- capprox
  4570   HFinite       <-- CFinite
  4571   HInfinite     <-- CInfinite
  4572   Infinitesimal <-- CInfinitesimal
  4573   monad         <-- cmonad
  4574   galaxy        <-- cgalaxy
  4575   (NS)LIM       <-- (NS)CLIM, (NS)CRLIM
  4576   is(NS)Cont    <-- is(NS)Contc, is(NS)contCR
  4577   (ns)deriv     <-- (ns)cderiv
  4578 
  4579 
  4580 *** HOL-Algebra ***
  4581 
  4582 * Formalisation of ideals and the quotient construction over rings.
  4583 
  4584 * Order and lattice theory no longer based on records.
  4585 INCOMPATIBILITY.
  4586 
  4587 * Renamed lemmas least_carrier -> least_closed and greatest_carrier ->
  4588 greatest_closed.  INCOMPATIBILITY.
  4589 
  4590 * Method algebra is now set up via an attribute.  For examples see
  4591 Ring.thy.  INCOMPATIBILITY: the method is now weaker on combinations
  4592 of algebraic structures.
  4593 
  4594 * Renamed theory CRing to Ring.
  4595 
  4596 
  4597 *** HOL-Nominal ***
  4598 
  4599 * Substantial, yet incomplete support for nominal datatypes (binding
  4600 structures) based on HOL-Nominal logic.  See src/HOL/Nominal and
  4601 src/HOL/Nominal/Examples.  Prospective users should consult
  4602 http://isabelle.in.tum.de/nominal/
  4603 
  4604 
  4605 *** ML ***
  4606 
  4607 * ML basics: just one true type int, which coincides with IntInf.int
  4608 (even on SML/NJ).
  4609 
  4610 * ML within Isar: antiquotations allow to embed statically-checked
  4611 formal entities in the source, referring to the context available at
  4612 compile-time.  For example:
  4613 
  4614 ML {* @{sort "{zero,one}"} *}
  4615 ML {* @{typ "'a => 'b"} *}
  4616 ML {* @{term "%x. x"} *}
  4617 ML {* @{prop "x == y"} *}
  4618 ML {* @{ctyp "'a => 'b"} *}
  4619 ML {* @{cterm "%x. x"} *}
  4620 ML {* @{cprop "x == y"} *}
  4621 ML {* @{thm asm_rl} *}
  4622 ML {* @{thms asm_rl} *}
  4623 ML {* @{type_name c} *}
  4624 ML {* @{type_syntax c} *}
  4625 ML {* @{const_name c} *}
  4626 ML {* @{const_syntax c} *}
  4627 ML {* @{context} *}
  4628 ML {* @{theory} *}
  4629 ML {* @{theory Pure} *}
  4630 ML {* @{theory_ref} *}
  4631 ML {* @{theory_ref Pure} *}
  4632 ML {* @{simpset} *}
  4633 ML {* @{claset} *}
  4634 ML {* @{clasimpset} *}
  4635 
  4636 The same works for sources being ``used'' within an Isar context.
  4637 
  4638 * ML in Isar: improved error reporting; extra verbosity with
  4639 ML_Context.trace enabled.
  4640 
  4641 * Pure/General/table.ML: the join operations now works via exceptions
  4642 DUP/SAME instead of type option. This is simpler in simple cases, and
  4643 admits slightly more efficient complex applications.
  4644 
  4645 * Pure: 'advanced' translation functions (parse_translation etc.) now
  4646 use Context.generic instead of just theory.
  4647 
  4648 * Pure: datatype Context.generic joins theory/Proof.context and
  4649 provides some facilities for code that works in either kind of
  4650 context, notably GenericDataFun for uniform theory and proof data.
  4651 
  4652 * Pure: simplified internal attribute type, which is now always
  4653 Context.generic * thm -> Context.generic * thm. Global (theory) vs.
  4654 local (Proof.context) attributes have been discontinued, while
  4655 minimizing code duplication. Thm.rule_attribute and
  4656 Thm.declaration_attribute build canonical attributes; see also structure
  4657 Context for further operations on Context.generic, notably
  4658 GenericDataFun. INCOMPATIBILITY, need to adapt attribute type
  4659 declarations and definitions.
  4660 
  4661 * Context data interfaces (Theory/Proof/GenericDataFun): removed
  4662 name/print, uninitialized data defaults to ad-hoc copy of empty value,
  4663 init only required for impure data. INCOMPATIBILITY: empty really need
  4664 to be empty (no dependencies on theory content!)
  4665 
  4666 * Pure/kernel: consts certification ignores sort constraints given in
  4667 signature declarations. (This information is not relevant to the
  4668 logic, but only for type inference.) SIGNIFICANT INTERNAL CHANGE,
  4669 potential INCOMPATIBILITY.
  4670 
  4671 * Pure: axiomatic type classes are now purely definitional, with
  4672 explicit proofs of class axioms and super class relations performed
  4673 internally. See Pure/axclass.ML for the main internal interfaces --
  4674 notably AxClass.define_class supercedes AxClass.add_axclass, and
  4675 AxClass.axiomatize_class/classrel/arity supersede
  4676 Sign.add_classes/classrel/arities.
  4677 
  4678 * Pure/Isar: Args/Attrib parsers operate on Context.generic --
  4679 global/local versions on theory vs. Proof.context have been
  4680 discontinued; Attrib.syntax and Method.syntax have been adapted
  4681 accordingly.  INCOMPATIBILITY, need to adapt parser expressions for
  4682 attributes, methods, etc.
  4683 
  4684 * Pure: several functions of signature "... -> theory -> theory * ..."
  4685 have been reoriented to "... -> theory -> ... * theory" in order to
  4686 allow natural usage in combination with the ||>, ||>>, |-> and
  4687 fold_map combinators.
  4688 
  4689 * Pure: official theorem names (closed derivations) and additional
  4690 comments (tags) are now strictly separate.  Name hints -- which are
  4691 maintained as tags -- may be attached any time without affecting the
  4692 derivation.
  4693 
  4694 * Pure: primitive rule lift_rule now takes goal cterm instead of an
  4695 actual goal state (thm).  Use Thm.lift_rule (Thm.cprem_of st i) to
  4696 achieve the old behaviour.
  4697 
  4698 * Pure: the "Goal" constant is now called "prop", supporting a
  4699 slightly more general idea of ``protecting'' meta-level rule
  4700 statements.
  4701 
  4702 * Pure: Logic.(un)varify only works in a global context, which is now
  4703 enforced instead of silently assumed.  INCOMPATIBILITY, may use
  4704 Logic.legacy_(un)varify as temporary workaround.
  4705 
  4706 * Pure: structure Name provides scalable operations for generating
  4707 internal variable names, notably Name.variants etc.  This replaces
  4708 some popular functions from term.ML:
  4709 
  4710   Term.variant		->  Name.variant
  4711   Term.variantlist	->  Name.variant_list
  4712   Term.invent_names	->  Name.invent_list
  4713 
  4714 Note that low-level renaming rarely occurs in new code -- operations
  4715 from structure Variable are used instead (see below).
  4716 
  4717 * Pure: structure Variable provides fundamental operations for proper
  4718 treatment of fixed/schematic variables in a context.  For example,
  4719 Variable.import introduces fixes for schematics of given facts and
  4720 Variable.export reverses the effect (up to renaming) -- this replaces
  4721 various freeze_thaw operations.
  4722 
  4723 * Pure: structure Goal provides simple interfaces for
  4724 init/conclude/finish and tactical prove operations (replacing former
  4725 Tactic.prove).  Goal.prove is the canonical way to prove results
  4726 within a given context; Goal.prove_global is a degraded version for
  4727 theory level goals, including a global Drule.standard.  Note that
  4728 OldGoals.prove_goalw_cterm has long been obsolete, since it is
  4729 ill-behaved in a local proof context (e.g. with local fixes/assumes or
  4730 in a locale context).
  4731 
  4732 * Pure/Syntax: generic interfaces for parsing (Syntax.parse_term etc.)
  4733 and type checking (Syntax.check_term etc.), with common combinations
  4734 (Syntax.read_term etc.). These supersede former Sign.read_term etc.
  4735 which are considered legacy and await removal.
  4736 
  4737 * Pure/Syntax: generic interfaces for type unchecking
  4738 (Syntax.uncheck_terms etc.) and unparsing (Syntax.unparse_term etc.),
  4739 with common combinations (Syntax.pretty_term, Syntax.string_of_term
  4740 etc.).  Former Sign.pretty_term, Sign.string_of_term etc. are still
  4741 available for convenience, but refer to the very same operations using
  4742 a mere theory instead of a full context.
  4743 
  4744 * Isar: simplified treatment of user-level errors, using exception
  4745 ERROR of string uniformly.  Function error now merely raises ERROR,
  4746 without any side effect on output channels.  The Isar toplevel takes
  4747 care of proper display of ERROR exceptions.  ML code may use plain
  4748 handle/can/try; cat_error may be used to concatenate errors like this:
  4749 
  4750   ... handle ERROR msg => cat_error msg "..."
  4751 
  4752 Toplevel ML code (run directly or through the Isar toplevel) may be
  4753 embedded into the Isar toplevel with exception display/debug like
  4754 this:
  4755 
  4756   Isar.toplevel (fn () => ...)
  4757 
  4758 INCOMPATIBILITY, removed special transform_error facilities, removed
  4759 obsolete variants of user-level exceptions (ERROR_MESSAGE,
  4760 Context.PROOF, ProofContext.CONTEXT, Proof.STATE, ProofHistory.FAIL)
  4761 -- use plain ERROR instead.
  4762 
  4763 * Isar: theory setup now has type (theory -> theory), instead of a
  4764 list.  INCOMPATIBILITY, may use #> to compose setup functions.
  4765 
  4766 * Isar: ML toplevel pretty printer for type Proof.context, subject to
  4767 ProofContext.debug/verbose flags.
  4768 
  4769 * Isar: Toplevel.theory_to_proof admits transactions that modify the
  4770 theory before entering a proof state.  Transactions now always see a
  4771 quasi-functional intermediate checkpoint, both in interactive and
  4772 batch mode.
  4773 
  4774 * Isar: simplified interfaces for outer syntax.  Renamed
  4775 OuterSyntax.add_keywords to OuterSyntax.keywords.  Removed
  4776 OuterSyntax.add_parsers -- this functionality is now included in
  4777 OuterSyntax.command etc.  INCOMPATIBILITY.
  4778 
  4779 * Simplifier: the simpset of a running simplification process now
  4780 contains a proof context (cf. Simplifier.the_context), which is the
  4781 very context that the initial simpset has been retrieved from (by
  4782 simpset_of/local_simpset_of).  Consequently, all plug-in components
  4783 (solver, looper etc.) may depend on arbitrary proof data.
  4784 
  4785 * Simplifier.inherit_context inherits the proof context (plus the
  4786 local bounds) of the current simplification process; any simproc
  4787 etc. that calls the Simplifier recursively should do this!  Removed
  4788 former Simplifier.inherit_bounds, which is already included here --
  4789 INCOMPATIBILITY.  Tools based on low-level rewriting may even have to
  4790 specify an explicit context using Simplifier.context/theory_context.
  4791 
  4792 * Simplifier/Classical Reasoner: more abstract interfaces
  4793 change_simpset/claset for modifying the simpset/claset reference of a
  4794 theory; raw versions simpset/claset_ref etc. have been discontinued --
  4795 INCOMPATIBILITY.
  4796 
  4797 * Provers: more generic wrt. syntax of object-logics, avoid hardwired
  4798 "Trueprop" etc.
  4799 
  4800 
  4801 *** System ***
  4802 
  4803 * settings: the default heap location within ISABELLE_HOME_USER now
  4804 includes ISABELLE_IDENTIFIER.  This simplifies use of multiple
  4805 Isabelle installations.
  4806 
  4807 * isabelle-process: option -S (secure mode) disables some critical
  4808 operations, notably runtime compilation and evaluation of ML source
  4809 code.
  4810 
  4811 * Basic Isabelle mode for jEdit, see Isabelle/lib/jedit/.
  4812 
  4813 * Support for parallel execution, using native multicore support of
  4814 Poly/ML 5.1.  The theory loader exploits parallelism when processing
  4815 independent theories, according to the given theory header
  4816 specifications. The maximum number of worker threads is specified via
  4817 usedir option -M or the "max-threads" setting in Proof General. A
  4818 speedup factor of 1.5--3.5 can be expected on a 4-core machine, and up
  4819 to 6 on a 8-core machine.  User-code needs to observe certain
  4820 guidelines for thread-safe programming, see appendix A in the Isar
  4821 Implementation manual.
  4822 
  4823 
  4824 
  4825 New in Isabelle2005 (October 2005)
  4826 ----------------------------------
  4827 
  4828 *** General ***
  4829 
  4830 * Theory headers: the new header syntax for Isar theories is
  4831 
  4832   theory <name>
  4833   imports <theory1> ... <theoryN>
  4834   uses <file1> ... <fileM>
  4835   begin
  4836 
  4837 where the 'uses' part is optional.  The previous syntax
  4838 
  4839   theory <name> = <theory1> + ... + <theoryN>:
  4840 
  4841 will disappear in the next release.  Use isatool fixheaders to convert
  4842 existing theory files.  Note that there is no change in ancient
  4843 non-Isar theories now, but these will disappear soon.
  4844 
  4845 * Theory loader: parent theories can now also be referred to via
  4846 relative and absolute paths.
  4847 
  4848 * Command 'find_theorems' searches for a list of criteria instead of a
  4849 list of constants. Known criteria are: intro, elim, dest, name:string,
  4850 simp:term, and any term. Criteria can be preceded by '-' to select
  4851 theorems that do not match. Intro, elim, dest select theorems that
  4852 match the current goal, name:s selects theorems whose fully qualified
  4853 name contain s, and simp:term selects all simplification rules whose
  4854 lhs match term.  Any other term is interpreted as pattern and selects
  4855 all theorems matching the pattern. Available in ProofGeneral under
  4856 'ProofGeneral -> Find Theorems' or C-c C-f.  Example:
  4857 
  4858   C-c C-f (100) "(_::nat) + _ + _" intro -name: "HOL."
  4859 
  4860 prints the last 100 theorems matching the pattern "(_::nat) + _ + _",
  4861 matching the current goal as introduction rule and not having "HOL."
  4862 in their name (i.e. not being defined in theory HOL).
  4863 
  4864 * Command 'thms_containing' has been discontinued in favour of
  4865 'find_theorems'; INCOMPATIBILITY.
  4866 
  4867 * Communication with Proof General is now 8bit clean, which means that
  4868 Unicode text in UTF-8 encoding may be used within theory texts (both
  4869 formal and informal parts).  Cf. option -U of the Isabelle Proof
  4870 General interface.  Here are some simple examples (cf. src/HOL/ex):
  4871 
  4872   http://isabelle.in.tum.de/library/HOL/ex/Hebrew.html
  4873   http://isabelle.in.tum.de/library/HOL/ex/Chinese.html
  4874 
  4875 * Improved efficiency of the Simplifier and, to a lesser degree, the
  4876 Classical Reasoner.  Typical big applications run around 2 times
  4877 faster.
  4878 
  4879 
  4880 *** Document preparation ***
  4881 
  4882 * Commands 'display_drafts' and 'print_drafts' perform simple output
  4883 of raw sources.  Only those symbols that do not require additional
  4884 LaTeX packages (depending on comments in isabellesym.sty) are
  4885 displayed properly, everything else is left verbatim.  isatool display
  4886 and isatool print are used as front ends (these are subject to the
  4887 DVI/PDF_VIEWER and PRINT_COMMAND settings, respectively).
  4888 
  4889 * Command tags control specific markup of certain regions of text,
  4890 notably folding and hiding.  Predefined tags include "theory" (for
  4891 theory begin and end), "proof" for proof commands, and "ML" for
  4892 commands involving ML code; the additional tags "visible" and
  4893 "invisible" are unused by default.  Users may give explicit tag
  4894 specifications in the text, e.g. ''by %invisible (auto)''.  The
  4895 interpretation of tags is determined by the LaTeX job during document
  4896 preparation: see option -V of isatool usedir, or options -n and -t of
  4897 isatool document, or even the LaTeX macros \isakeeptag, \isafoldtag,
  4898 \isadroptag.
  4899 
  4900 Several document versions may be produced at the same time via isatool
  4901 usedir (the generated index.html will link all of them).  Typical
  4902 specifications include ''-V document=theory,proof,ML'' to present
  4903 theory/proof/ML parts faithfully, ''-V outline=/proof,/ML'' to fold
  4904 proof and ML commands, and ''-V mutilated=-theory,-proof,-ML'' to omit
  4905 these parts without any formal replacement text.  The Isabelle site
  4906 default settings produce ''document'' and ''outline'' versions as
  4907 specified above.
  4908 
  4909 * Several new antiquotations:
  4910 
  4911   @{term_type term} prints a term with its type annotated;
  4912 
  4913   @{typeof term} prints the type of a term;
  4914 
  4915   @{const const} is the same as @{term const}, but checks that the
  4916   argument is a known logical constant;
  4917 
  4918   @{term_style style term} and @{thm_style style thm} print a term or
  4919   theorem applying a "style" to it
  4920 
  4921   @{ML text}
  4922 
  4923 Predefined styles are 'lhs' and 'rhs' printing the lhs/rhs of
  4924 definitions, equations, inequations etc., 'concl' printing only the
  4925 conclusion of a meta-logical statement theorem, and 'prem1' .. 'prem19'
  4926 to print the specified premise.  TermStyle.add_style provides an ML
  4927 interface for introducing further styles.  See also the "LaTeX Sugar"
  4928 document practical applications.  The ML antiquotation prints
  4929 type-checked ML expressions verbatim.
  4930 
  4931 * Markup commands 'chapter', 'section', 'subsection', 'subsubsection',
  4932 and 'text' support optional locale specification '(in loc)', which
  4933 specifies the default context for interpreting antiquotations.  For
  4934 example: 'text (in lattice) {* @{thm inf_assoc}*}'.
  4935 
  4936 * Option 'locale=NAME' of antiquotations specifies an alternative
  4937 context interpreting the subsequent argument.  For example: @{thm
  4938 [locale=lattice] inf_assoc}.
  4939 
  4940 * Proper output of proof terms (@{prf ...} and @{full_prf ...}) within
  4941 a proof context.
  4942 
  4943 * Proper output of antiquotations for theory commands involving a
  4944 proof context (such as 'locale' or 'theorem (in loc) ...').
  4945 
  4946 * Delimiters of outer tokens (string etc.) now produce separate LaTeX
  4947 macros (\isachardoublequoteopen, isachardoublequoteclose etc.).
  4948 
  4949 * isatool usedir: new option -C (default true) controls whether option
  4950 -D should include a copy of the original document directory; -C false
  4951 prevents unwanted effects such as copying of administrative CVS data.
  4952 
  4953 
  4954 *** Pure ***
  4955 
  4956 * Considerably improved version of 'constdefs' command.  Now performs
  4957 automatic type-inference of declared constants; additional support for
  4958 local structure declarations (cf. locales and HOL records), see also
  4959 isar-ref manual.  Potential INCOMPATIBILITY: need to observe strictly
  4960 sequential dependencies of definitions within a single 'constdefs'
  4961 section; moreover, the declared name needs to be an identifier.  If
  4962 all fails, consider to fall back on 'consts' and 'defs' separately.
  4963 
  4964 * Improved indexed syntax and implicit structures.  First of all,
  4965 indexed syntax provides a notational device for subscripted
  4966 application, using the new syntax \<^bsub>term\<^esub> for arbitrary
  4967 expressions.  Secondly, in a local context with structure
  4968 declarations, number indexes \<^sub>n or the empty index (default
  4969 number 1) refer to a certain fixed variable implicitly; option
  4970 show_structs controls printing of implicit structures.  Typical
  4971 applications of these concepts involve record types and locales.
  4972 
  4973 * New command 'no_syntax' removes grammar declarations (and
  4974 translations) resulting from the given syntax specification, which is
  4975 interpreted in the same manner as for the 'syntax' command.
  4976 
  4977 * 'Advanced' translation functions (parse_translation etc.) may depend
  4978 on the signature of the theory context being presently used for
  4979 parsing/printing, see also isar-ref manual.
  4980 
  4981 * Improved 'oracle' command provides a type-safe interface to turn an
  4982 ML expression of type theory -> T -> term into a primitive rule of
  4983 type theory -> T -> thm (i.e. the functionality of Thm.invoke_oracle
  4984 is already included here); see also FOL/ex/IffExample.thy;
  4985 INCOMPATIBILITY.
  4986 
  4987 * axclass: name space prefix for class "c" is now "c_class" (was "c"
  4988 before); "cI" is no longer bound, use "c.intro" instead.
  4989 INCOMPATIBILITY.  This change avoids clashes of fact bindings for
  4990 axclasses vs. locales.
  4991 
  4992 * Improved internal renaming of symbolic identifiers -- attach primes
  4993 instead of base 26 numbers.
  4994 
  4995 * New flag show_question_marks controls printing of leading question
  4996 marks in schematic variable names.
  4997 
  4998 * In schematic variable names, *any* symbol following \<^isub> or
  4999 \<^isup> is now treated as part of the base name.  For example, the
  5000 following works without printing of awkward ".0" indexes:
  5001 
  5002   lemma "x\<^isub>1 = x\<^isub>2 ==> x\<^isub>2 = x\<^isub>1"
  5003     by simp
  5004 
  5005 * Inner syntax includes (*(*nested*) comments*).
  5006 
  5007 * Pretty printer now supports unbreakable blocks, specified in mixfix
  5008 annotations as "(00...)".
  5009 
  5010 * Clear separation of logical types and nonterminals, where the latter
  5011 may only occur in 'syntax' specifications or type abbreviations.
  5012 Before that distinction was only partially implemented via type class
  5013 "logic" vs. "{}".  Potential INCOMPATIBILITY in rare cases of improper
  5014 use of 'types'/'consts' instead of 'nonterminals'/'syntax'.  Some very
  5015 exotic syntax specifications may require further adaption
  5016 (e.g. Cube/Cube.thy).
  5017 
  5018 * Removed obsolete type class "logic", use the top sort {} instead.
  5019 Note that non-logical types should be declared as 'nonterminals'
  5020 rather than 'types'.  INCOMPATIBILITY for new object-logic
  5021 specifications.
  5022 
  5023 * Attributes 'induct' and 'cases': type or set names may now be
  5024 locally fixed variables as well.
  5025 
  5026 * Simplifier: can now control the depth to which conditional rewriting
  5027 is traced via the PG menu Isabelle -> Settings -> Trace Simp Depth
  5028 Limit.
  5029 
  5030 * Simplifier: simplification procedures may now take the current
  5031 simpset into account (cf. Simplifier.simproc(_i) / mk_simproc
  5032 interface), which is very useful for calling the Simplifier
  5033 recursively.  Minor INCOMPATIBILITY: the 'prems' argument of simprocs
  5034 is gone -- use prems_of_ss on the simpset instead.  Moreover, the
  5035 low-level mk_simproc no longer applies Logic.varify internally, to
  5036 allow for use in a context of fixed variables.
  5037 
  5038 * thin_tac now works even if the assumption being deleted contains !!
  5039 or ==>.  More generally, erule now works even if the major premise of
  5040 the elimination rule contains !! or ==>.
  5041 
  5042 * Method 'rules' has been renamed to 'iprover'. INCOMPATIBILITY.
  5043 
  5044 * Reorganized bootstrapping of the Pure theories; CPure is now derived
  5045 from Pure, which contains all common declarations already.  Both
  5046 theories are defined via plain Isabelle/Isar .thy files.
  5047 INCOMPATIBILITY: elements of CPure (such as the CPure.intro /
  5048 CPure.elim / CPure.dest attributes) now appear in the Pure name space;
  5049 use isatool fixcpure to adapt your theory and ML sources.
  5050 
  5051 * New syntax 'name(i-j, i-, i, ...)' for referring to specific
  5052 selections of theorems in named facts via index ranges.
  5053 
  5054 * 'print_theorems': in theory mode, really print the difference
  5055 wrt. the last state (works for interactive theory development only),
  5056 in proof mode print all local facts (cf. 'print_facts');
  5057 
  5058 * 'hide': option '(open)' hides only base names.
  5059 
  5060 * More efficient treatment of intermediate checkpoints in interactive
  5061 theory development.
  5062 
  5063 * Code generator is now invoked via code_module (incremental code
  5064 generation) and code_library (modular code generation, ML structures
  5065 for each theory).  INCOMPATIBILITY: new keywords 'file' and 'contains'
  5066 must be quoted when used as identifiers.
  5067 
  5068 * New 'value' command for reading, evaluating and printing terms using
  5069 the code generator.  INCOMPATIBILITY: command keyword 'value' must be
  5070 quoted when used as identifier.
  5071 
  5072 
  5073 *** Locales ***
  5074 
  5075 * New commands for the interpretation of locale expressions in
  5076 theories (1), locales (2) and proof contexts (3).  These generate
  5077 proof obligations from the expression specification.  After the
  5078 obligations have been discharged, theorems of the expression are added
  5079 to the theory, target locale or proof context.  The synopsis of the
  5080 commands is a follows:
  5081 
  5082   (1) interpretation expr inst
  5083   (2) interpretation target < expr
  5084   (3) interpret expr inst
  5085 
  5086 Interpretation in theories and proof contexts require a parameter
  5087 instantiation of terms from the current context.  This is applied to
  5088 specifications and theorems of the interpreted expression.
  5089 Interpretation in locales only permits parameter renaming through the
  5090 locale expression.  Interpretation is smart in that interpretations
  5091 that are active already do not occur in proof obligations, neither are
  5092 instantiated theorems stored in duplicate.  Use 'print_interps' to
  5093 inspect active interpretations of a particular locale.  For details,
  5094 see the Isar Reference manual.  Examples can be found in
  5095 HOL/Finite_Set.thy and HOL/Algebra/UnivPoly.thy.
  5096 
  5097 INCOMPATIBILITY: former 'instantiate' has been withdrawn, use
  5098 'interpret' instead.
  5099 
  5100 * New context element 'constrains' for adding type constraints to
  5101 parameters.
  5102 
  5103 * Context expressions: renaming of parameters with syntax
  5104 redeclaration.
  5105 
  5106 * Locale declaration: 'includes' disallowed.
  5107 
  5108 * Proper static binding of attribute syntax -- i.e. types / terms /
  5109 facts mentioned as arguments are always those of the locale definition
  5110 context, independently of the context of later invocations.  Moreover,
  5111 locale operations (renaming and type / term instantiation) are applied
  5112 to attribute arguments as expected.
  5113 
  5114 INCOMPATIBILITY of the ML interface: always pass Attrib.src instead of
  5115 actual attributes; rare situations may require Attrib.attribute to
  5116 embed those attributes into Attrib.src that lack concrete syntax.
  5117 Attribute implementations need to cooperate properly with the static
  5118 binding mechanism.  Basic parsers Args.XXX_typ/term/prop and
  5119 Attrib.XXX_thm etc. already do the right thing without further
  5120 intervention.  Only unusual applications -- such as "where" or "of"
  5121 (cf. src/Pure/Isar/attrib.ML), which process arguments depending both
  5122 on the context and the facts involved -- may have to assign parsed
  5123 values to argument tokens explicitly.
  5124 
  5125 * Changed parameter management in theorem generation for long goal
  5126 statements with 'includes'.  INCOMPATIBILITY: produces a different
  5127 theorem statement in rare situations.
  5128 
  5129 * Locale inspection command 'print_locale' omits notes elements.  Use
  5130 'print_locale!' to have them included in the output.
  5131 
  5132 
  5133 *** Provers ***
  5134 
  5135 * Provers/hypsubst.ML: improved version of the subst method, for
  5136 single-step rewriting: it now works in bound variable contexts. New is
  5137 'subst (asm)', for rewriting an assumption.  INCOMPATIBILITY: may
  5138 rewrite a different subterm than the original subst method, which is
  5139 still available as 'simplesubst'.
  5140 
  5141 * Provers/quasi.ML: new transitivity reasoners for transitivity only
  5142 and quasi orders.
  5143 
  5144 * Provers/trancl.ML: new transitivity reasoner for transitive and
  5145 reflexive-transitive closure of relations.
  5146 
  5147 * Provers/blast.ML: new reference depth_limit to make blast's depth
  5148 limit (previously hard-coded with a value of 20) user-definable.
  5149 
  5150 * Provers/simplifier.ML has been moved to Pure, where Simplifier.setup
  5151 is peformed already.  Object-logics merely need to finish their
  5152 initial simpset configuration as before.  INCOMPATIBILITY.
  5153 
  5154 
  5155 *** HOL ***
  5156 
  5157 * Symbolic syntax of Hilbert Choice Operator is now as follows:
  5158 
  5159   syntax (epsilon)
  5160     "_Eps" :: "[pttrn, bool] => 'a"    ("(3\<some>_./ _)" [0, 10] 10)
  5161 
  5162 The symbol \<some> is displayed as the alternative epsilon of LaTeX
  5163 and x-symbol; use option '-m epsilon' to get it actually printed.
  5164 Moreover, the mathematically important symbolic identifier \<epsilon>
  5165 becomes available as variable, constant etc.  INCOMPATIBILITY,
  5166 
  5167 * "x > y" abbreviates "y < x" and "x >= y" abbreviates "y <= x".
  5168 Similarly for all quantifiers: "ALL x > y" etc.  The x-symbol for >=
  5169 is \<ge>. New transitivity rules have been added to HOL/Orderings.thy to
  5170 support corresponding Isar calculations.
  5171 
  5172 * "{x:A. P}" abbreviates "{x. x:A & P}", and similarly for "\<in>"
  5173 instead of ":".
  5174 
  5175 * theory SetInterval: changed the syntax for open intervals:
  5176 
  5177   Old       New
  5178   {..n(}    {..<n}
  5179   {)n..}    {n<..}
  5180   {m..n(}   {m..<n}
  5181   {)m..n}   {m<..n}
  5182   {)m..n(}  {m<..<n}
  5183 
  5184 The old syntax is still supported but will disappear in the next
  5185 release.  For conversion use the following Emacs search and replace
  5186 patterns (these are not perfect but work quite well):
  5187 
  5188   {)\([^\.]*\)\.\.  ->  {\1<\.\.}
  5189   \.\.\([^(}]*\)(}  ->  \.\.<\1}
  5190 
  5191 * Theory Commutative_Ring (in Library): method comm_ring for proving
  5192 equalities in commutative rings; method 'algebra' provides a generic
  5193 interface.
  5194 
  5195 * Theory Finite_Set: changed the syntax for 'setsum', summation over
  5196 finite sets: "setsum (%x. e) A", which used to be "\<Sum>x:A. e", is
  5197 now either "SUM x:A. e" or "\<Sum>x \<in> A. e". The bound variable can
  5198 be a tuple pattern.
  5199 
  5200 Some new syntax forms are available:
  5201 
  5202   "\<Sum>x | P. e"      for     "setsum (%x. e) {x. P}"
  5203   "\<Sum>x = a..b. e"   for     "setsum (%x. e) {a..b}"
  5204   "\<Sum>x = a..<b. e"  for     "setsum (%x. e) {a..<b}"
  5205   "\<Sum>x < k. e"      for     "setsum (%x. e) {..<k}"
  5206 
  5207 The latter form "\<Sum>x < k. e" used to be based on a separate
  5208 function "Summation", which has been discontinued.
  5209 
  5210 * theory Finite_Set: in structured induction proofs, the insert case
  5211 is now 'case (insert x F)' instead of the old counterintuitive 'case
  5212 (insert F x)'.
  5213 
  5214 * The 'refute' command has been extended to support a much larger
  5215 fragment of HOL, including axiomatic type classes, constdefs and
  5216 typedefs, inductive datatypes and recursion.
  5217 
  5218 * New tactics 'sat' and 'satx' to prove propositional tautologies.
  5219 Requires zChaff with proof generation to be installed.  See
  5220 HOL/ex/SAT_Examples.thy for examples.
  5221 
  5222 * Datatype induction via method 'induct' now preserves the name of the
  5223 induction variable. For example, when proving P(xs::'a list) by
  5224 induction on xs, the induction step is now P(xs) ==> P(a#xs) rather
  5225 than P(list) ==> P(a#list) as previously.  Potential INCOMPATIBILITY
  5226 in unstructured proof scripts.
  5227 
  5228 * Reworked implementation of records.  Improved scalability for
  5229 records with many fields, avoiding performance problems for type
  5230 inference. Records are no longer composed of nested field types, but
  5231 of nested extension types. Therefore the record type only grows linear
  5232 in the number of extensions and not in the number of fields.  The
  5233 top-level (users) view on records is preserved.  Potential
  5234 INCOMPATIBILITY only in strange cases, where the theory depends on the
  5235 old record representation. The type generated for a record is called
  5236 <record_name>_ext_type.
  5237 
  5238 Flag record_quick_and_dirty_sensitive can be enabled to skip the
  5239 proofs triggered by a record definition or a simproc (if
  5240 quick_and_dirty is enabled).  Definitions of large records can take
  5241 quite long.
  5242 
  5243 New simproc record_upd_simproc for simplification of multiple record
  5244 updates enabled by default.  Moreover, trivial updates are also
  5245 removed: r(|x := x r|) = r.  INCOMPATIBILITY: old proofs break
  5246 occasionally, since simplification is more powerful by default.
  5247 
  5248 * typedef: proper support for polymorphic sets, which contain extra
  5249 type-variables in the term.
  5250 
  5251 * Simplifier: automatically reasons about transitivity chains
  5252 involving "trancl" (r^+) and "rtrancl" (r^*) by setting up tactics
  5253 provided by Provers/trancl.ML as additional solvers.  INCOMPATIBILITY:
  5254 old proofs break occasionally as simplification may now solve more
  5255 goals than previously.
  5256 
  5257 * Simplifier: converts x <= y into x = y if assumption y <= x is
  5258 present.  Works for all partial orders (class "order"), in particular
  5259 numbers and sets.  For linear orders (e.g. numbers) it treats ~ x < y
  5260 just like y <= x.
  5261 
  5262 * Simplifier: new simproc for "let x = a in f x".  If a is a free or
  5263 bound variable or a constant then the let is unfolded.  Otherwise
  5264 first a is simplified to b, and then f b is simplified to g. If
  5265 possible we abstract b from g arriving at "let x = b in h x",
  5266 otherwise we unfold the let and arrive at g.  The simproc can be
  5267 enabled/disabled by the reference use_let_simproc.  Potential
  5268 INCOMPATIBILITY since simplification is more powerful by default.
  5269 
  5270 * Classical reasoning: the meson method now accepts theorems as arguments.
  5271 
  5272 * Prover support: pre-release of the Isabelle-ATP linkup, which runs background
  5273 jobs to provide advice on the provability of subgoals.
  5274 
  5275 * Theory OrderedGroup and Ring_and_Field: various additions and
  5276 improvements to faciliate calculations involving equalities and
  5277 inequalities.
  5278 
  5279 The following theorems have been eliminated or modified
  5280 (INCOMPATIBILITY):
  5281 
  5282   abs_eq             now named abs_of_nonneg
  5283   abs_of_ge_0        now named abs_of_nonneg
  5284   abs_minus_eq       now named abs_of_nonpos
  5285   imp_abs_id         now named abs_of_nonneg
  5286   imp_abs_neg_id     now named abs_of_nonpos
  5287   mult_pos           now named mult_pos_pos
  5288   mult_pos_le        now named mult_nonneg_nonneg
  5289   mult_pos_neg_le    now named mult_nonneg_nonpos
  5290   mult_pos_neg2_le   now named mult_nonneg_nonpos2
  5291   mult_neg           now named mult_neg_neg
  5292   mult_neg_le        now named mult_nonpos_nonpos
  5293 
  5294 * The following lemmas in Ring_and_Field have been added to the simplifier:
  5295      
  5296      zero_le_square
  5297      not_square_less_zero 
  5298 
  5299   The following lemmas have been deleted from Real/RealPow:
  5300   
  5301      realpow_zero_zero
  5302      realpow_two
  5303      realpow_less
  5304      zero_le_power
  5305      realpow_two_le
  5306      abs_realpow_two
  5307      realpow_two_abs     
  5308 
  5309 * Theory Parity: added rules for simplifying exponents.
  5310 
  5311 * Theory List:
  5312 
  5313 The following theorems have been eliminated or modified
  5314 (INCOMPATIBILITY):
  5315 
  5316   list_all_Nil       now named list_all.simps(1)
  5317   list_all_Cons      now named list_all.simps(2)
  5318   list_all_conv      now named list_all_iff
  5319   set_mem_eq         now named mem_iff
  5320 
  5321 * Theories SetsAndFunctions and BigO (see HOL/Library) support
  5322 asymptotic "big O" calculations.  See the notes in BigO.thy.
  5323 
  5324 
  5325 *** HOL-Complex ***
  5326 
  5327 * Theory RealDef: better support for embedding natural numbers and
  5328 integers in the reals.
  5329 
  5330 The following theorems have been eliminated or modified
  5331 (INCOMPATIBILITY):
  5332 
  5333   exp_ge_add_one_self  now requires no hypotheses
  5334   real_of_int_add      reversed direction of equality (use [symmetric])
  5335   real_of_int_minus    reversed direction of equality (use [symmetric])
  5336   real_of_int_diff     reversed direction of equality (use [symmetric])
  5337   real_of_int_mult     reversed direction of equality (use [symmetric])
  5338 
  5339 * Theory RComplete: expanded support for floor and ceiling functions.
  5340 
  5341 * Theory Ln is new, with properties of the natural logarithm
  5342 
  5343 * Hyperreal: There is a new type constructor "star" for making
  5344 nonstandard types.  The old type names are now type synonyms:
  5345 
  5346   hypreal = real star
  5347   hypnat = nat star
  5348   hcomplex = complex star
  5349 
  5350 * Hyperreal: Many groups of similarly-defined constants have been
  5351 replaced by polymorphic versions (INCOMPATIBILITY):
  5352 
  5353   star_of <-- hypreal_of_real, hypnat_of_nat, hcomplex_of_complex
  5354 
  5355   starset      <-- starsetNat, starsetC
  5356   *s*          <-- *sNat*, *sc*
  5357   starset_n    <-- starsetNat_n, starsetC_n
  5358   *sn*         <-- *sNatn*, *scn*
  5359   InternalSets <-- InternalNatSets, InternalCSets
  5360 
  5361   starfun      <-- starfun{Nat,Nat2,C,RC,CR}
  5362   *f*          <-- *fNat*, *fNat2*, *fc*, *fRc*, *fcR*
  5363   starfun_n    <-- starfun{Nat,Nat2,C,RC,CR}_n
  5364   *fn*         <-- *fNatn*, *fNat2n*, *fcn*, *fRcn*, *fcRn*
  5365   InternalFuns <-- InternalNatFuns, InternalNatFuns2, Internal{C,RC,CR}Funs
  5366 
  5367 * Hyperreal: Many type-specific theorems have been removed in favor of
  5368 theorems specific to various axiomatic type classes (INCOMPATIBILITY):
  5369 
  5370   add_commute <-- {hypreal,hypnat,hcomplex}_add_commute
  5371   add_assoc   <-- {hypreal,hypnat,hcomplex}_add_assocs
  5372   OrderedGroup.add_0 <-- {hypreal,hypnat,hcomplex}_add_zero_left
  5373   OrderedGroup.add_0_right <-- {hypreal,hcomplex}_add_zero_right
  5374   right_minus <-- hypreal_add_minus
  5375   left_minus <-- {hypreal,hcomplex}_add_minus_left
  5376   mult_commute <-- {hypreal,hypnat,hcomplex}_mult_commute
  5377   mult_assoc <-- {hypreal,hypnat,hcomplex}_mult_assoc
  5378   mult_1_left <-- {hypreal,hypnat}_mult_1, hcomplex_mult_one_left
  5379   mult_1_right <-- hcomplex_mult_one_right
  5380   mult_zero_left <-- hcomplex_mult_zero_left
  5381   left_distrib <-- {hypreal,hypnat,hcomplex}_add_mult_distrib
  5382   right_distrib <-- hypnat_add_mult_distrib2
  5383   zero_neq_one <-- {hypreal,hypnat,hcomplex}_zero_not_eq_one
  5384   right_inverse <-- hypreal_mult_inverse
  5385   left_inverse <-- hypreal_mult_inverse_left, hcomplex_mult_inv_left
  5386   order_refl <-- {hypreal,hypnat}_le_refl
  5387   order_trans <-- {hypreal,hypnat}_le_trans
  5388   order_antisym <-- {hypreal,hypnat}_le_anti_sym
  5389   order_less_le <-- {hypreal,hypnat}_less_le
  5390   linorder_linear <-- {hypreal,hypnat}_le_linear
  5391   add_left_mono <-- {hypreal,hypnat}_add_left_mono
  5392   mult_strict_left_mono <-- {hypreal,hypnat}_mult_less_mono2
  5393   add_nonneg_nonneg <-- hypreal_le_add_order
  5394 
  5395 * Hyperreal: Separate theorems having to do with type-specific
  5396 versions of constants have been merged into theorems that apply to the
  5397 new polymorphic constants (INCOMPATIBILITY):
  5398 
  5399   STAR_UNIV_set <-- {STAR_real,NatStar_real,STARC_complex}_set
  5400   STAR_empty_set <-- {STAR,NatStar,STARC}_empty_set
  5401   STAR_Un <-- {STAR,NatStar,STARC}_Un
  5402   STAR_Int <-- {STAR,NatStar,STARC}_Int
  5403   STAR_Compl <-- {STAR,NatStar,STARC}_Compl
  5404   STAR_subset <-- {STAR,NatStar,STARC}_subset
  5405   STAR_mem <-- {STAR,NatStar,STARC}_mem
  5406   STAR_mem_Compl <-- {STAR,STARC}_mem_Compl
  5407   STAR_diff <-- {STAR,STARC}_diff
  5408   STAR_star_of_image_subset <-- {STAR_hypreal_of_real, NatStar_hypreal_of_real,
  5409     STARC_hcomplex_of_complex}_image_subset
  5410   starset_n_Un <-- starset{Nat,C}_n_Un
  5411   starset_n_Int <-- starset{Nat,C}_n_Int
  5412   starset_n_Compl <-- starset{Nat,C}_n_Compl
  5413   starset_n_diff <-- starset{Nat,C}_n_diff
  5414   InternalSets_Un <-- Internal{Nat,C}Sets_Un
  5415   InternalSets_Int <-- Internal{Nat,C}Sets_Int
  5416   InternalSets_Compl <-- Internal{Nat,C}Sets_Compl
  5417   InternalSets_diff <-- Internal{Nat,C}Sets_diff
  5418   InternalSets_UNIV_diff <-- Internal{Nat,C}Sets_UNIV_diff
  5419   InternalSets_starset_n <-- Internal{Nat,C}Sets_starset{Nat,C}_n
  5420   starset_starset_n_eq <-- starset{Nat,C}_starset{Nat,C}_n_eq
  5421   starset_n_starset <-- starset{Nat,C}_n_starset{Nat,C}
  5422   starfun_n_starfun <-- starfun{Nat,Nat2,C,RC,CR}_n_starfun{Nat,Nat2,C,RC,CR}
  5423   starfun <-- starfun{Nat,Nat2,C,RC,CR}
  5424   starfun_mult <-- starfun{Nat,Nat2,C,RC,CR}_mult
  5425   starfun_add <-- starfun{Nat,Nat2,C,RC,CR}_add
  5426   starfun_minus <-- starfun{Nat,Nat2,C,RC,CR}_minus
  5427   starfun_diff <-- starfun{C,RC,CR}_diff
  5428   starfun_o <-- starfun{NatNat2,Nat2,_stafunNat,C,C_starfunRC,_starfunCR}_o
  5429   starfun_o2 <-- starfun{NatNat2,_stafunNat,C,C_starfunRC,_starfunCR}_o2
  5430   starfun_const_fun <-- starfun{Nat,Nat2,C,RC,CR}_const_fun
  5431   starfun_inverse <-- starfun{Nat,C,RC,CR}_inverse
  5432   starfun_eq <-- starfun{Nat,Nat2,C,RC,CR}_eq
  5433   starfun_eq_iff <-- starfun{C,RC,CR}_eq_iff
  5434   starfun_Id <-- starfunC_Id
  5435   starfun_approx <-- starfun{Nat,CR}_approx
  5436   starfun_capprox <-- starfun{C,RC}_capprox
  5437   starfun_abs <-- starfunNat_rabs
  5438   starfun_lambda_cancel <-- starfun{C,CR,RC}_lambda_cancel
  5439   starfun_lambda_cancel2 <-- starfun{C,CR,RC}_lambda_cancel2
  5440   starfun_mult_HFinite_approx <-- starfunCR_mult_HFinite_capprox
  5441   starfun_mult_CFinite_capprox <-- starfun{C,RC}_mult_CFinite_capprox
  5442   starfun_add_capprox <-- starfun{C,RC}_add_capprox
  5443   starfun_add_approx <-- starfunCR_add_approx
  5444   starfun_inverse_inverse <-- starfunC_inverse_inverse
  5445   starfun_divide <-- starfun{C,CR,RC}_divide
  5446   starfun_n <-- starfun{Nat,C}_n
  5447   starfun_n_mult <-- starfun{Nat,C}_n_mult
  5448   starfun_n_add <-- starfun{Nat,C}_n_add
  5449   starfun_n_add_minus <-- starfunNat_n_add_minus
  5450   starfun_n_const_fun <-- starfun{Nat,C}_n_const_fun
  5451   starfun_n_minus <-- starfun{Nat,C}_n_minus
  5452   starfun_n_eq <-- starfun{Nat,C}_n_eq
  5453 
  5454   star_n_add <-- {hypreal,hypnat,hcomplex}_add
  5455   star_n_minus <-- {hypreal,hcomplex}_minus
  5456   star_n_diff <-- {hypreal,hcomplex}_diff
  5457   star_n_mult <-- {hypreal,hcomplex}_mult
  5458   star_n_inverse <-- {hypreal,hcomplex}_inverse
  5459   star_n_le <-- {hypreal,hypnat}_le
  5460   star_n_less <-- {hypreal,hypnat}_less
  5461   star_n_zero_num <-- {hypreal,hypnat,hcomplex}_zero_num
  5462   star_n_one_num <-- {hypreal,hypnat,hcomplex}_one_num
  5463   star_n_abs <-- hypreal_hrabs
  5464   star_n_divide <-- hcomplex_divide
  5465 
  5466   star_of_add <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_add
  5467   star_of_minus <-- {hypreal_of_real,hcomplex_of_complex}_minus
  5468   star_of_diff <-- hypreal_of_real_diff
  5469   star_of_mult <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_mult
  5470   star_of_one <-- {hypreal_of_real,hcomplex_of_complex}_one
  5471   star_of_zero <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_zero
  5472   star_of_le <-- {hypreal_of_real,hypnat_of_nat}_le_iff
  5473   star_of_less <-- {hypreal_of_real,hypnat_of_nat}_less_iff
  5474   star_of_eq <-- {hypreal_of_real,hypnat_of_nat,hcomplex_of_complex}_eq_iff
  5475   star_of_inverse <-- {hypreal_of_real,hcomplex_of_complex}_inverse
  5476   star_of_divide <-- {hypreal_of_real,hcomplex_of_complex}_divide
  5477   star_of_of_nat <-- {hypreal_of_real,hcomplex_of_complex}_of_nat
  5478   star_of_of_int <-- {hypreal_of_real,hcomplex_of_complex}_of_int
  5479   star_of_number_of <-- {hypreal,hcomplex}_number_of
  5480   star_of_number_less <-- number_of_less_hypreal_of_real_iff
  5481   star_of_number_le <-- number_of_le_hypreal_of_real_iff
  5482   star_of_eq_number <-- hypreal_of_real_eq_number_of_iff
  5483   star_of_less_number <-- hypreal_of_real_less_number_of_iff
  5484   star_of_le_number <-- hypreal_of_real_le_number_of_iff
  5485   star_of_power <-- hypreal_of_real_power
  5486   star_of_eq_0 <-- hcomplex_of_complex_zero_iff
  5487 
  5488 * Hyperreal: new method "transfer" that implements the transfer
  5489 principle of nonstandard analysis. With a subgoal that mentions
  5490 nonstandard types like "'a star", the command "apply transfer"
  5491 replaces it with an equivalent one that mentions only standard types.
  5492 To be successful, all free variables must have standard types; non-
  5493 standard variables must have explicit universal quantifiers.
  5494 
  5495 * Hyperreal: A theory of Taylor series.
  5496 
  5497 
  5498 *** HOLCF ***
  5499 
  5500 * Discontinued special version of 'constdefs' (which used to support
  5501 continuous functions) in favor of the general Pure one with full
  5502 type-inference.
  5503 
  5504 * New simplification procedure for solving continuity conditions; it
  5505 is much faster on terms with many nested lambda abstractions (cubic
  5506 instead of exponential time).
  5507 
  5508 * New syntax for domain package: selector names are now optional.
  5509 Parentheses should be omitted unless argument is lazy, for example:
  5510 
  5511   domain 'a stream = cons "'a" (lazy "'a stream")
  5512 
  5513 * New command 'fixrec' for defining recursive functions with pattern
  5514 matching; defining multiple functions with mutual recursion is also
  5515 supported.  Patterns may include the constants cpair, spair, up, sinl,
  5516 sinr, or any data constructor defined by the domain package. The given
  5517 equations are proven as rewrite rules. See HOLCF/ex/Fixrec_ex.thy for
  5518 syntax and examples.
  5519 
  5520 * New commands 'cpodef' and 'pcpodef' for defining predicate subtypes
  5521 of cpo and pcpo types. Syntax is exactly like the 'typedef' command,
  5522 but the proof obligation additionally includes an admissibility
  5523 requirement. The packages generate instances of class cpo or pcpo,
  5524 with continuity and strictness theorems for Rep and Abs.
  5525 
  5526 * HOLCF: Many theorems have been renamed according to a more standard naming
  5527 scheme (INCOMPATIBILITY):
  5528 
  5529   foo_inject:  "foo$x = foo$y ==> x = y"
  5530   foo_eq:      "(foo$x = foo$y) = (x = y)"
  5531   foo_less:    "(foo$x << foo$y) = (x << y)"
  5532   foo_strict:  "foo$UU = UU"
  5533   foo_defined: "... ==> foo$x ~= UU"
  5534   foo_defined_iff: "(foo$x = UU) = (x = UU)"
  5535 
  5536 
  5537 *** ZF ***
  5538 
  5539 * ZF/ex: theories Group and Ring provide examples in abstract algebra,
  5540 including the First Isomorphism Theorem (on quotienting by the kernel
  5541 of a homomorphism).
  5542 
  5543 * ZF/Simplifier: install second copy of type solver that actually
  5544 makes use of TC rules declared to Isar proof contexts (or locales);
  5545 the old version is still required for ML proof scripts.
  5546 
  5547 
  5548 *** Cube ***
  5549 
  5550 * Converted to Isar theory format; use locales instead of axiomatic
  5551 theories.
  5552 
  5553 
  5554 *** ML ***
  5555 
  5556 * Pure/library.ML: added ##>, ##>>, #>> -- higher-order counterparts
  5557 for ||>, ||>>, |>>,
  5558 
  5559 * Pure/library.ML no longer defines its own option datatype, but uses
  5560 that of the SML basis, which has constructors NONE and SOME instead of
  5561 None and Some, as well as exception Option.Option instead of OPTION.
  5562 The functions the, if_none, is_some, is_none have been adapted
  5563 accordingly, while Option.map replaces apsome.
  5564 
  5565 * Pure/library.ML: the exception LIST has been given up in favour of
  5566 the standard exceptions Empty and Subscript, as well as
  5567 Library.UnequalLengths.  Function like Library.hd and Library.tl are
  5568 superceded by the standard hd and tl functions etc.
  5569 
  5570 A number of basic list functions are no longer exported to the ML
  5571 toplevel, as they are variants of predefined functions.  The following
  5572 suggests how one can translate existing code:
  5573 
  5574     rev_append xs ys = List.revAppend (xs, ys)
  5575     nth_elem (i, xs) = List.nth (xs, i)
  5576     last_elem xs = List.last xs
  5577     flat xss = List.concat xss
  5578     seq fs = List.app fs
  5579     partition P xs = List.partition P xs
  5580     mapfilter f xs = List.mapPartial f xs
  5581 
  5582 * Pure/library.ML: several combinators for linear functional
  5583 transformations, notably reverse application and composition:
  5584 
  5585   x |> f                f #> g
  5586   (x, y) |-> f          f #-> g
  5587 
  5588 * Pure/library.ML: introduced/changed precedence of infix operators:
  5589 
  5590   infix 1 |> |-> ||> ||>> |>> |>>> #> #->;
  5591   infix 2 ?;
  5592   infix 3 o oo ooo oooo;
  5593   infix 4 ~~ upto downto;
  5594 
  5595 Maybe INCOMPATIBILITY when any of those is used in conjunction with other
  5596 infix operators.
  5597 
  5598 * Pure/library.ML: natural list combinators fold, fold_rev, and
  5599 fold_map support linear functional transformations and nesting.  For
  5600 example:
  5601 
  5602   fold f [x1, ..., xN] y =
  5603     y |> f x1 |> ... |> f xN
  5604 
  5605   (fold o fold) f [xs1, ..., xsN] y =
  5606     y |> fold f xs1 |> ... |> fold f xsN
  5607 
  5608   fold f [x1, ..., xN] =
  5609     f x1 #> ... #> f xN
  5610 
  5611   (fold o fold) f [xs1, ..., xsN] =
  5612     fold f xs1 #> ... #> fold f xsN
  5613 
  5614 * Pure/library.ML: the following selectors on type 'a option are
  5615 available:
  5616 
  5617   the:               'a option -> 'a  (*partial*)
  5618   these:             'a option -> 'a  where 'a = 'b list
  5619   the_default: 'a -> 'a option -> 'a
  5620   the_list:          'a option -> 'a list
  5621 
  5622 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5623 basic operations for association lists, following natural argument
  5624 order; moreover the explicit equality predicate passed here avoids
  5625 potentially expensive polymorphic runtime equality checks.
  5626 The old functions may be expressed as follows:
  5627 
  5628   assoc = uncurry (AList.lookup (op =))
  5629   assocs = these oo AList.lookup (op =)
  5630   overwrite = uncurry (AList.update (op =)) o swap
  5631 
  5632 * Pure/General: structure AList (cf. Pure/General/alist.ML) provides
  5633 
  5634   val make: ('a -> 'b) -> 'a list -> ('a * 'b) list
  5635   val find: ('a * 'b -> bool) -> ('c * 'b) list -> 'a -> 'c list
  5636 
  5637 replacing make_keylist and keyfilter (occassionally used)
  5638 Naive rewrites:
  5639 
  5640   make_keylist = AList.make
  5641   keyfilter = AList.find (op =)
  5642 
  5643 * eq_fst and eq_snd now take explicit equality parameter, thus
  5644   avoiding eqtypes. Naive rewrites:
  5645 
  5646     eq_fst = eq_fst (op =)
  5647     eq_snd = eq_snd (op =)
  5648 
  5649 * Removed deprecated apl and apr (rarely used).
  5650   Naive rewrites:
  5651 
  5652     apl (n, op) =>>= curry op n
  5653     apr (op, m) =>>= fn n => op (n, m)
  5654 
  5655 * Pure/General: structure OrdList (cf. Pure/General/ord_list.ML)
  5656 provides a reasonably efficient light-weight implementation of sets as
  5657 lists.
  5658 
  5659 * Pure/General: generic tables (cf. Pure/General/table.ML) provide a
  5660 few new operations; existing lookup and update are now curried to
  5661 follow natural argument order (for use with fold etc.);
  5662 INCOMPATIBILITY, use (uncurry Symtab.lookup) etc. as last resort.
  5663 
  5664 * Pure/General: output via the Isabelle channels of
  5665 writeln/warning/error etc. is now passed through Output.output, with a
  5666 hook for arbitrary transformations depending on the print_mode
  5667 (cf. Output.add_mode -- the first active mode that provides a output
  5668 function wins).  Already formatted output may be embedded into further
  5669 text via Output.raw; the result of Pretty.string_of/str_of and derived
  5670 functions (string_of_term/cterm/thm etc.) is already marked raw to
  5671 accommodate easy composition of diagnostic messages etc.  Programmers
  5672 rarely need to care about Output.output or Output.raw at all, with
  5673 some notable exceptions: Output.output is required when bypassing the
  5674 standard channels (writeln etc.), or in token translations to produce
  5675 properly formatted results; Output.raw is required when capturing
  5676 already output material that will eventually be presented to the user
  5677 a second time.  For the default print mode, both Output.output and
  5678 Output.raw have no effect.
  5679 
  5680 * Pure/General: Output.time_accumulator NAME creates an operator ('a
  5681 -> 'b) -> 'a -> 'b to measure runtime and count invocations; the
  5682 cumulative results are displayed at the end of a batch session.
  5683 
  5684 * Pure/General: File.sysify_path and File.quote_sysify path have been
  5685 replaced by File.platform_path and File.shell_path (with appropriate
  5686 hooks).  This provides a clean interface for unusual systems where the
  5687 internal and external process view of file names are different.
  5688 
  5689 * Pure: more efficient orders for basic syntactic entities: added
  5690 fast_string_ord, fast_indexname_ord, fast_term_ord; changed sort_ord
  5691 and typ_ord to use fast_string_ord and fast_indexname_ord (term_ord is
  5692 NOT affected); structures Symtab, Vartab, Typtab, Termtab use the fast
  5693 orders now -- potential INCOMPATIBILITY for code that depends on a
  5694 particular order for Symtab.keys, Symtab.dest, etc. (consider using
  5695 Library.sort_strings on result).
  5696 
  5697 * Pure/term.ML: combinators fold_atyps, fold_aterms, fold_term_types,
  5698 fold_types traverse types/terms from left to right, observing natural
  5699 argument order.  Supercedes previous foldl_XXX versions, add_frees,
  5700 add_vars etc. have been adapted as well: INCOMPATIBILITY.
  5701 
  5702 * Pure: name spaces have been refined, with significant changes of the
  5703 internal interfaces -- INCOMPATIBILITY.  Renamed cond_extern(_table)
  5704 to extern(_table).  The plain name entry path is superceded by a
  5705 general 'naming' context, which also includes the 'policy' to produce
  5706 a fully qualified name and external accesses of a fully qualified
  5707 name; NameSpace.extend is superceded by context dependent
  5708 Sign.declare_name.  Several theory and proof context operations modify
  5709 the naming context.  Especially note Theory.restore_naming and
  5710 ProofContext.restore_naming to get back to a sane state; note that
  5711 Theory.add_path is no longer sufficient to recover from
  5712 Theory.absolute_path in particular.
  5713 
  5714 * Pure: new flags short_names (default false) and unique_names
  5715 (default true) for controlling output of qualified names.  If
  5716 short_names is set, names are printed unqualified.  If unique_names is
  5717 reset, the name prefix is reduced to the minimum required to achieve
  5718 the original result when interning again, even if there is an overlap
  5719 with earlier declarations.
  5720 
  5721 * Pure/TheoryDataFun: change of the argument structure; 'prep_ext' is
  5722 now 'extend', and 'merge' gets an additional Pretty.pp argument
  5723 (useful for printing error messages).  INCOMPATIBILITY.
  5724 
  5725 * Pure: major reorganization of the theory context.  Type Sign.sg and
  5726 Theory.theory are now identified, referring to the universal
  5727 Context.theory (see Pure/context.ML).  Actual signature and theory
  5728 content is managed as theory data.  The old code and interfaces were
  5729 spread over many files and structures; the new arrangement introduces
  5730 considerable INCOMPATIBILITY to gain more clarity:
  5731 
  5732   Context -- theory management operations (name, identity, inclusion,
  5733     parents, ancestors, merge, etc.), plus generic theory data;
  5734 
  5735   Sign -- logical signature and syntax operations (declaring consts,
  5736     types, etc.), plus certify/read for common entities;
  5737 
  5738   Theory -- logical theory operations (stating axioms, definitions,
  5739     oracles), plus a copy of logical signature operations (consts,
  5740     types, etc.); also a few basic management operations (Theory.copy,
  5741     Theory.merge, etc.)
  5742 
  5743 The most basic sign_of operations (Theory.sign_of, Thm.sign_of_thm
  5744 etc.) as well as the sign field in Thm.rep_thm etc. have been retained
  5745 for convenience -- they merely return the theory.
  5746 
  5747 * Pure: type Type.tsig is superceded by theory in most interfaces.
  5748 
  5749 * Pure: the Isar proof context type is already defined early in Pure
  5750 as Context.proof (note that ProofContext.context and Proof.context are
  5751 aliases, where the latter is the preferred name).  This enables other
  5752 Isabelle components to refer to that type even before Isar is present.
  5753 
  5754 * Pure/sign/theory: discontinued named name spaces (i.e. classK,
  5755 typeK, constK, axiomK, oracleK), but provide explicit operations for
  5756 any of these kinds.  For example, Sign.intern typeK is now
  5757 Sign.intern_type, Theory.hide_space Sign.typeK is now
  5758 Theory.hide_types.  Also note that former
  5759 Theory.hide_classes/types/consts are now
  5760 Theory.hide_classes_i/types_i/consts_i, while the non '_i' versions
  5761 internalize their arguments!  INCOMPATIBILITY.
  5762 
  5763 * Pure: get_thm interface (of PureThy and ProofContext) expects
  5764 datatype thmref (with constructors Name and NameSelection) instead of
  5765 plain string -- INCOMPATIBILITY;
  5766 
  5767 * Pure: cases produced by proof methods specify options, where NONE
  5768 means to remove case bindings -- INCOMPATIBILITY in
  5769 (RAW_)METHOD_CASES.
  5770 
  5771 * Pure: the following operations retrieve axioms or theorems from a
  5772 theory node or theory hierarchy, respectively:
  5773 
  5774   Theory.axioms_of: theory -> (string * term) list
  5775   Theory.all_axioms_of: theory -> (string * term) list
  5776   PureThy.thms_of: theory -> (string * thm) list
  5777   PureThy.all_thms_of: theory -> (string * thm) list
  5778 
  5779 * Pure: print_tac now outputs the goal through the trace channel.
  5780 
  5781 * Isar toplevel: improved diagnostics, mostly for Poly/ML only.
  5782 Reference Toplevel.debug (default false) controls detailed printing
  5783 and tracing of low-level exceptions; Toplevel.profiling (default 0)
  5784 controls execution profiling -- set to 1 for time and 2 for space
  5785 (both increase the runtime).
  5786 
  5787 * Isar session: The initial use of ROOT.ML is now always timed,
  5788 i.e. the log will show the actual process times, in contrast to the
  5789 elapsed wall-clock time that the outer shell wrapper produces.
  5790 
  5791 * Simplifier: improved handling of bound variables (nameless
  5792 representation, avoid allocating new strings).  Simprocs that invoke
  5793 the Simplifier recursively should use Simplifier.inherit_bounds to
  5794 avoid local name clashes.  Failure to do so produces warnings
  5795 "Simplifier: renamed bound variable ..."; set Simplifier.debug_bounds
  5796 for further details.
  5797 
  5798 * ML functions legacy_bindings and use_legacy_bindings produce ML fact
  5799 bindings for all theorems stored within a given theory; this may help
  5800 in porting non-Isar theories to Isar ones, while keeping ML proof
  5801 scripts for the time being.
  5802 
  5803 * ML operator HTML.with_charset specifies the charset begin used for
  5804 generated HTML files.  For example:
  5805 
  5806   HTML.with_charset "utf-8" use_thy "Hebrew";
  5807   HTML.with_charset "utf-8" use_thy "Chinese";
  5808 
  5809 
  5810 *** System ***
  5811 
  5812 * Allow symlinks to all proper Isabelle executables (Isabelle,
  5813 isabelle, isatool etc.).
  5814 
  5815 * ISABELLE_DOC_FORMAT setting specifies preferred document format (for
  5816 isatool doc, isatool mkdir, display_drafts etc.).
  5817 
  5818 * isatool usedir: option -f allows specification of the ML file to be
  5819 used by Isabelle; default is ROOT.ML.
  5820 
  5821 * New isatool version outputs the version identifier of the Isabelle
  5822 distribution being used.
  5823 
  5824 * HOL: new isatool dimacs2hol converts files in DIMACS CNF format
  5825 (containing Boolean satisfiability problems) into Isabelle/HOL
  5826 theories.
  5827 
  5828 
  5829 
  5830 New in Isabelle2004 (April 2004)
  5831 --------------------------------
  5832 
  5833 *** General ***
  5834 
  5835 * Provers/order.ML:  new efficient reasoner for partial and linear orders.
  5836   Replaces linorder.ML.
  5837 
  5838 * Pure: Greek letters (except small lambda, \<lambda>), as well as Gothic
  5839   (\<aa>...\<zz>\<AA>...\<ZZ>), calligraphic (\<A>...\<Z>), and Euler
  5840   (\<a>...\<z>), are now considered normal letters, and can therefore
  5841   be used anywhere where an ASCII letter (a...zA...Z) has until
  5842   now. COMPATIBILITY: This obviously changes the parsing of some
  5843   terms, especially where a symbol has been used as a binder, say
  5844   '\<Pi>x. ...', which is now a type error since \<Pi>x will be parsed
  5845   as an identifier.  Fix it by inserting a space around former
  5846   symbols.  Call 'isatool fixgreek' to try to fix parsing errors in
  5847   existing theory and ML files.
  5848 
  5849 * Pure: Macintosh and Windows line-breaks are now allowed in theory files.
  5850 
  5851 * Pure: single letter sub/superscripts (\<^isub> and \<^isup>) are now
  5852   allowed in identifiers. Similar to Greek letters \<^isub> is now considered
  5853   a normal (but invisible) letter. For multiple letter subscripts repeat
  5854   \<^isub> like this: x\<^isub>1\<^isub>2.
  5855 
  5856 * Pure: There are now sub-/superscripts that can span more than one
  5857   character. Text between \<^bsub> and \<^esub> is set in subscript in
  5858   ProofGeneral and LaTeX, text between \<^bsup> and \<^esup> in
  5859   superscript. The new control characters are not identifier parts.
  5860 
  5861 * Pure: Control-symbols of the form \<^raw:...> will literally print the
  5862   content of "..." to the latex file instead of \isacntrl... . The "..."
  5863   may consist of any printable characters excluding the end bracket >.
  5864 
  5865 * Pure: Using new Isar command "finalconsts" (or the ML functions
  5866   Theory.add_finals or Theory.add_finals_i) it is now possible to
  5867   declare constants "final", which prevents their being given a definition
  5868   later.  It is useful for constants whose behaviour is fixed axiomatically
  5869   rather than definitionally, such as the meta-logic connectives.
  5870 
  5871 * Pure: 'instance' now handles general arities with general sorts
  5872   (i.e. intersections of classes),
  5873 
  5874 * Presentation: generated HTML now uses a CSS style sheet to make layout
  5875   (somewhat) independent of content. It is copied from lib/html/isabelle.css.
  5876   It can be changed to alter the colors/layout of generated pages.
  5877 
  5878 
  5879 *** Isar ***
  5880 
  5881 * Tactic emulation methods rule_tac, erule_tac, drule_tac, frule_tac,
  5882   cut_tac, subgoal_tac and thin_tac:
  5883   - Now understand static (Isar) contexts.  As a consequence, users of Isar
  5884     locales are no longer forced to write Isar proof scripts.
  5885     For details see Isar Reference Manual, paragraph 4.3.2: Further tactic
  5886     emulations.
  5887   - INCOMPATIBILITY: names of variables to be instantiated may no
  5888     longer be enclosed in quotes.  Instead, precede variable name with `?'.
  5889     This is consistent with the instantiation attribute "where".
  5890 
  5891 * Attributes "where" and "of":
  5892   - Now take type variables of instantiated theorem into account when reading
  5893     the instantiation string.  This fixes a bug that caused instantiated
  5894     theorems to have too special types in some circumstances.
  5895   - "where" permits explicit instantiations of type variables.
  5896 
  5897 * Calculation commands "moreover" and "also" no longer interfere with
  5898   current facts ("this"), admitting arbitrary combinations with "then"
  5899   and derived forms.
  5900 
  5901 * Locales:
  5902   - Goal statements involving the context element "includes" no longer
  5903     generate theorems with internal delta predicates (those ending on
  5904     "_axioms") in the premise.
  5905     Resolve particular premise with <locale>.intro to obtain old form.
  5906   - Fixed bug in type inference ("unify_frozen") that prevented mix of target
  5907     specification and "includes" elements in goal statement.
  5908   - Rule sets <locale>.intro and <locale>.axioms no longer declared as
  5909     [intro?] and [elim?] (respectively) by default.
  5910   - Experimental command for instantiation of locales in proof contexts:
  5911         instantiate <label>[<attrs>]: <loc>
  5912     Instantiates locale <loc> and adds all its theorems to the current context
  5913     taking into account their attributes.  Label and attrs are optional
  5914     modifiers, like in theorem declarations.  If present, names of
  5915     instantiated theorems are qualified with <label>, and the attributes
  5916     <attrs> are applied after any attributes these theorems might have already.
  5917       If the locale has assumptions, a chained fact of the form
  5918     "<loc> t1 ... tn" is expected from which instantiations of the parameters
  5919     are derived.  The command does not support old-style locales declared
  5920     with "locale (open)".
  5921       A few (very simple) examples can be found in FOL/ex/LocaleInst.thy.
  5922 
  5923 * HOL: Tactic emulation methods induct_tac and case_tac understand static
  5924   (Isar) contexts.
  5925 
  5926 
  5927 *** HOL ***
  5928 
  5929 * Proof import: new image HOL4 contains the imported library from
  5930   the HOL4 system with about 2500 theorems. It is imported by
  5931   replaying proof terms produced by HOL4 in Isabelle. The HOL4 image
  5932   can be used like any other Isabelle image.  See
  5933   HOL/Import/HOL/README for more information.
  5934 
  5935 * Simplifier:
  5936   - Much improved handling of linear and partial orders.
  5937     Reasoners for linear and partial orders are set up for type classes
  5938     "linorder" and "order" respectively, and are added to the default simpset
  5939     as solvers.  This means that the simplifier can build transitivity chains
  5940     to solve goals from the assumptions.
  5941   - INCOMPATIBILITY: old proofs break occasionally.  Typically, applications
  5942     of blast or auto after simplification become unnecessary because the goal
  5943     is solved by simplification already.
  5944 
  5945 * Numerics: new theory Ring_and_Field contains over 250 basic numerical laws,
  5946     all proved in axiomatic type classes for semirings, rings and fields.
  5947 
  5948 * Numerics:
  5949   - Numeric types (nat, int, and in HOL-Complex rat, real, complex, etc.) are
  5950     now formalized using the Ring_and_Field theory mentioned above.
  5951   - INCOMPATIBILITY: simplification and arithmetic behaves somewhat differently
  5952     than before, because now they are set up once in a generic manner.
  5953   - INCOMPATIBILITY: many type-specific arithmetic laws have gone.
  5954     Look for the general versions in Ring_and_Field (and Power if they concern
  5955     exponentiation).
  5956 
  5957 * Type "rat" of the rational numbers is now available in HOL-Complex.
  5958 
  5959 * Records:
  5960   - Record types are now by default printed with their type abbreviation
  5961     instead of the list of all field types. This can be configured via
  5962     the reference "print_record_type_abbr".
  5963   - Simproc "record_upd_simproc" for simplification of multiple updates added
  5964     (not enabled by default).
  5965   - Simproc "record_ex_sel_eq_simproc" to simplify EX x. sel r = x resp.
  5966     EX x. x = sel r to True (not enabled by default).
  5967   - Tactic "record_split_simp_tac" to split and simplify records added.
  5968 
  5969 * 'specification' command added, allowing for definition by
  5970   specification.  There is also an 'ax_specification' command that
  5971   introduces the new constants axiomatically.
  5972 
  5973 * arith(_tac) is now able to generate counterexamples for reals as well.
  5974 
  5975 * HOL-Algebra: new locale "ring" for non-commutative rings.
  5976 
  5977 * HOL-ex: InductiveInvariant_examples illustrates advanced recursive function
  5978   definitions, thanks to Sava Krsti\'{c} and John Matthews.
  5979 
  5980 * HOL-Matrix: a first theory for matrices in HOL with an application of
  5981   matrix theory to linear programming.
  5982 
  5983 * Unions and Intersections:
  5984   The latex output syntax of UN and INT has been changed
  5985   from "\Union x \in A. B" to "\Union_{x \in A} B"
  5986   i.e. the index formulae has become a subscript.
  5987   Similarly for "\Union x. B", and for \Inter instead of \Union.
  5988 
  5989 * Unions and Intersections over Intervals:
  5990   There is new short syntax "UN i<=n. A" for "UN i:{0..n}. A". There is
  5991   also an x-symbol version with subscripts "\<Union>\<^bsub>i <= n\<^esub>. A"
  5992   like in normal math, and corresponding versions for < and for intersection.
  5993 
  5994 * HOL/List: Ordering "lexico" is renamed "lenlex" and the standard
  5995   lexicographic dictonary ordering has been added as "lexord".
  5996 
  5997 * ML: the legacy theory structures Int and List have been removed. They had
  5998   conflicted with ML Basis Library structures having the same names.
  5999 
  6000 * 'refute' command added to search for (finite) countermodels.  Only works
  6001   for a fragment of HOL.  The installation of an external SAT solver is
  6002   highly recommended.  See "HOL/Refute.thy" for details.
  6003 
  6004 * 'quickcheck' command: Allows to find counterexamples by evaluating
  6005   formulae under an assignment of free variables to random values.
  6006   In contrast to 'refute', it can deal with inductive datatypes,
  6007   but cannot handle quantifiers. See "HOL/ex/Quickcheck_Examples.thy"
  6008   for examples.
  6009 
  6010 
  6011 *** HOLCF ***
  6012 
  6013 * Streams now come with concatenation and are part of the HOLCF image
  6014 
  6015 
  6016 
  6017 New in Isabelle2003 (May 2003)
  6018 ------------------------------
  6019 
  6020 *** General ***
  6021 
  6022 * Provers/simplifier:
  6023 
  6024   - Completely reimplemented method simp (ML: Asm_full_simp_tac):
  6025     Assumptions are now subject to complete mutual simplification,
  6026     not just from left to right. The simplifier now preserves
  6027     the order of assumptions.
  6028 
  6029     Potential INCOMPATIBILITY:
  6030 
  6031     -- simp sometimes diverges where the old version did
  6032        not, e.g. invoking simp on the goal
  6033 
  6034         [| P (f x); y = x; f x = f y |] ==> Q
  6035 
  6036        now gives rise to the infinite reduction sequence
  6037 
  6038         P(f x) --(f x = f y)--> P(f y) --(y = x)--> P(f x) --(f x = f y)--> ...
  6039 
  6040        Using "simp (asm_lr)" (ML: Asm_lr_simp_tac) instead often solves this
  6041        kind of problem.
  6042 
  6043     -- Tactics combining classical reasoner and simplification (such as auto)
  6044        are also affected by this change, because many of them rely on
  6045        simp. They may sometimes diverge as well or yield a different numbers
  6046        of subgoals. Try to use e.g. force, fastsimp, or safe instead of auto
  6047        in case of problems. Sometimes subsequent calls to the classical
  6048        reasoner will fail because a preceeding call to the simplifier too
  6049        eagerly simplified the goal, e.g. deleted redundant premises.
  6050 
  6051   - The simplifier trace now shows the names of the applied rewrite rules
  6052 
  6053   - You can limit the number of recursive invocations of the simplifier
  6054     during conditional rewriting (where the simplifie tries to solve the
  6055     conditions before applying the rewrite rule):
  6056     ML "simp_depth_limit := n"
  6057     where n is an integer. Thus you can force termination where previously
  6058     the simplifier would diverge.
  6059 
  6060   - Accepts free variables as head terms in congruence rules.  Useful in Isar.
  6061 
  6062   - No longer aborts on failed congruence proof.  Instead, the
  6063     congruence is ignored.
  6064 
  6065 * Pure: New generic framework for extracting programs from constructive
  6066   proofs. See HOL/Extraction.thy for an example instantiation, as well
  6067   as HOL/Extraction for some case studies.
  6068 
  6069 * Pure: The main goal of the proof state is no longer shown by default, only
  6070 the subgoals. This behaviour is controlled by a new flag.
  6071    PG menu: Isabelle/Isar -> Settings -> Show Main Goal
  6072 (ML: Proof.show_main_goal).
  6073 
  6074 * Pure: You can find all matching introduction rules for subgoal 1, i.e. all
  6075 rules whose conclusion matches subgoal 1:
  6076       PG menu: Isabelle/Isar -> Show me -> matching rules
  6077 The rules are ordered by how closely they match the subgoal.
  6078 In particular, rules that solve a subgoal outright are displayed first
  6079 (or rather last, the way they are printed).
  6080 (ML: ProofGeneral.print_intros())
  6081 
  6082 * Pure: New flag trace_unify_fail causes unification to print
  6083 diagnostic information (PG: in trace buffer) when it fails. This is
  6084 useful for figuring out why single step proofs like rule, erule or
  6085 assumption failed.
  6086 
  6087 * Pure: Locale specifications now produce predicate definitions
  6088 according to the body of text (covering assumptions modulo local
  6089 definitions); predicate "loc_axioms" covers newly introduced text,
  6090 while "loc" is cumulative wrt. all included locale expressions; the
  6091 latter view is presented only on export into the global theory
  6092 context; potential INCOMPATIBILITY, use "(open)" option to fall back
  6093 on the old view without predicates;
  6094 
  6095 * Pure: predefined locales "var" and "struct" are useful for sharing
  6096 parameters (as in CASL, for example); just specify something like
  6097 ``var x + var y + struct M'' as import;
  6098 
  6099 * Pure: improved thms_containing: proper indexing of facts instead of
  6100 raw theorems; check validity of results wrt. current name space;
  6101 include local facts of proof configuration (also covers active
  6102 locales), cover fixed variables in index; may use "_" in term
  6103 specification; an optional limit for the number of printed facts may
  6104 be given (the default is 40);
  6105 
  6106 * Pure: disallow duplicate fact bindings within new-style theory files
  6107 (batch-mode only);
  6108 
  6109 * Provers: improved induct method: assumptions introduced by case
  6110 "foo" are split into "foo.hyps" (from the rule) and "foo.prems" (from
  6111 the goal statement); "foo" still refers to all facts collectively;
  6112 
  6113 * Provers: the function blast.overloaded has been removed: all constants
  6114 are regarded as potentially overloaded, which improves robustness in exchange
  6115 for slight decrease in efficiency;
  6116 
  6117 * Provers/linorder: New generic prover for transitivity reasoning over
  6118 linear orders.  Note: this prover is not efficient!
  6119 
  6120 * Isar: preview of problems to finish 'show' now produce an error
  6121 rather than just a warning (in interactive mode);
  6122 
  6123 
  6124 *** HOL ***
  6125 
  6126 * arith(_tac)
  6127 
  6128  - Produces a counter example if it cannot prove a goal.
  6129    Note that the counter example may be spurious if the goal is not a formula
  6130    of quantifier-free linear arithmetic.
  6131    In ProofGeneral the counter example appears in the trace buffer.
  6132 
  6133  - Knows about div k and mod k where k is a numeral of type nat or int.
  6134 
  6135  - Calls full Presburger arithmetic (by Amine Chaieb) if quantifier-free
  6136    linear arithmetic fails. This takes account of quantifiers and divisibility.
  6137    Presburger arithmetic can also be called explicitly via presburger(_tac).
  6138 
  6139 * simp's arithmetic capabilities have been enhanced a bit: it now
  6140 takes ~= in premises into account (by performing a case split);
  6141 
  6142 * simp reduces "m*(n div m) + n mod m" to n, even if the two summands
  6143 are distributed over a sum of terms;
  6144 
  6145 * New tactic "trans_tac" and method "trans" instantiate
  6146 Provers/linorder.ML for axclasses "order" and "linorder" (predicates
  6147 "<=", "<" and "=").
  6148 
  6149 * function INCOMPATIBILITIES: Pi-sets have been redefined and moved from main
  6150 HOL to Library/FuncSet; constant "Fun.op o" is now called "Fun.comp";
  6151 
  6152 * 'typedef' command has new option "open" to suppress the set
  6153 definition;
  6154 
  6155 * functions Min and Max on finite sets have been introduced (theory
  6156 Finite_Set);
  6157 
  6158 * attribute [symmetric] now works for relations as well; it turns
  6159 (x,y) : R^-1 into (y,x) : R, and vice versa;
  6160 
  6161 * induct over a !!-quantified statement (say !!x1..xn):
  6162   each "case" automatically performs "fix x1 .. xn" with exactly those names.
  6163 
  6164 * Map: `empty' is no longer a constant but a syntactic abbreviation for
  6165 %x. None. Warning: empty_def now refers to the previously hidden definition
  6166 of the empty set.
  6167 
  6168 * Algebra: formalization of classical algebra.  Intended as base for
  6169 any algebraic development in Isabelle.  Currently covers group theory
  6170 (up to Sylow's theorem) and ring theory (Universal Property of
  6171 Univariate Polynomials).  Contributions welcome;
  6172 
  6173 * GroupTheory: deleted, since its material has been moved to Algebra;
  6174 
  6175 * Complex: new directory of the complex numbers with numeric constants,
  6176 nonstandard complex numbers, and some complex analysis, standard and
  6177 nonstandard (Jacques Fleuriot);
  6178 
  6179 * HOL-Complex: new image for analysis, replacing HOL-Real and HOL-Hyperreal;
  6180 
  6181 * Hyperreal: introduced Gauge integration and hyperreal logarithms (Jacques
  6182 Fleuriot);
  6183 
  6184 * Real/HahnBanach: updated and adapted to locales;
  6185 
  6186 * NumberTheory: added Gauss's law of quadratic reciprocity (by Avigad,
  6187 Gray and Kramer);
  6188 
  6189 * UNITY: added the Meier-Sanders theory of progress sets;
  6190 
  6191 * MicroJava: bytecode verifier and lightweight bytecode verifier
  6192 as abstract algorithms, instantiated to the JVM;
  6193 
  6194 * Bali: Java source language formalization. Type system, operational
  6195 semantics, axiomatic semantics. Supported language features:
  6196 classes, interfaces, objects,virtual methods, static methods,
  6197 static/instance fields, arrays, access modifiers, definite
  6198 assignment, exceptions.
  6199 
  6200 
  6201 *** ZF ***
  6202 
  6203 * ZF/Constructible: consistency proof for AC (Gdel's constructible
  6204 universe, etc.);
  6205 
  6206 * Main ZF: virtually all theories converted to new-style format;
  6207 
  6208 
  6209 *** ML ***
  6210 
  6211 * Pure: Tactic.prove provides sane interface for internal proofs;
  6212 omits the infamous "standard" operation, so this is more appropriate
  6213 than prove_goalw_cterm in many situations (e.g. in simprocs);
  6214 
  6215 * Pure: improved error reporting of simprocs;
  6216 
  6217 * Provers: Simplifier.simproc(_i) provides sane interface for setting
  6218 up simprocs;
  6219 
  6220 
  6221 *** Document preparation ***
  6222 
  6223 * uses \par instead of \\ for line breaks in theory text. This may
  6224 shift some page breaks in large documents. To get the old behaviour
  6225 use \renewcommand{\isanewline}{\mbox{}\\\mbox{}} in root.tex.
  6226 
  6227 * minimized dependencies of isabelle.sty and isabellesym.sty on
  6228 other packages
  6229 
  6230 * \<euro> now needs package babel/greek instead of marvosym (which
  6231 broke \Rightarrow)
  6232 
  6233 * normal size for \<zero>...\<nine> (uses \mathbf instead