NEWS
author wenzelm
Fri Dec 19 10:13:47 1997 +0100 (1997-12-19)
changeset 4440 9ed4098074bc
parent 4410 b68047c56fce
child 4502 337c073de95e
permissions -rw-r--r--
adapted to new sort function;
     1 
     2 Isabelle NEWS -- history of user-visible changes
     3 ================================================
     4 
     5 New in Isabelle98 (January 1998)
     6 --------------------------------
     7 
     8 *** Overview of INCOMPATIBILITIES (see below for more details) ***
     9 
    10 * changed lexical syntax of terms / types: dots made part of long
    11 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
    12 
    13 * simpset (and claset) reference variable replaced by functions
    14 simpset / simpset_ref;
    15 
    16 * no longer supports theory aliases (via merge) and non-trivial
    17 implicit merge of thms' signatures;
    18 
    19 * most internal names of constants changed due to qualified names;
    20 
    21 * changed Pure/Sequence interface (see Pure/seq.ML);
    22 
    23 
    24 *** General Changes ***
    25 
    26 * hierachically structured name spaces (for consts, types, axms, thms
    27 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
    28 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
    29 isatool fixdots ensures space after dots (e.g. "%x. x"); set
    30 long_names for fully qualified output names; NOTE: ML programs
    31 (special tactics, packages etc.) referring to internal names may have
    32 to be adapted to cope with fully qualified names; in case of severe
    33 backward campatibility problems try setting 'global_names' at compile
    34 time to have enrything declared within a flat name space; one may also
    35 fine tune name declarations in theories via the 'global' and 'local'
    36 section;
    37 
    38 * reimplemented the implicit simpset and claset using the new anytype
    39 data filed in signatures; references simpset:simpset ref etc. are
    40 replaced by functions simpset:unit->simpset and
    41 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
    42 to patch your ML files accordingly;
    43 
    44 * HTML output now includes theory graph data for display with Java
    45 applet or isatool browser; data generated automatically via isatool
    46 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
    47 
    48 * defs may now be conditional; improved rewrite_goals_tac to handle
    49 conditional equations;
    50 
    51 * defs now admits additional type arguments, using TYPE('a) syntax;
    52 
    53 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
    54 creates a new theory node; implicit merge of thms' signatures is
    55 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
    56 transfer:theory->thm->thm in (rare) cases;
    57 
    58 * improved handling of draft signatures / theories; draft thms (and
    59 ctyps, cterms) are automatically promoted to real ones;
    60 
    61 * slightly changed interfaces for oracles: admit many per theory, named
    62 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
    63 
    64 * print_goals: optional output of const types (set show_consts and
    65 show_types);
    66 
    67 * improved output of warnings (###) and errors (***);
    68 
    69 * subgoal_tac displays a warning if the new subgoal has type variables;
    70 
    71 * removed old README and Makefiles;
    72 
    73 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
    74 
    75 * removed obsolete init_pps and init_database;
    76 
    77 * deleted the obsolete tactical STATE, which was declared by
    78     fun STATE tacfun st = tacfun st st;
    79 
    80 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
    81 (which abbreviates $HOME);
    82 
    83 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
    84 use isatool fixseq to adapt your ML programs (this works for fully
    85 qualified references to the Sequence structure only!);
    86 
    87 * use_thy no longer requires writable current directory; it always
    88 reloads .ML *and* .thy file, if either one is out of date;
    89 
    90 
    91 *** Classical Reasoner ***
    92 
    93 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
    94 tactics that use classical reasoning to simplify a subgoal without
    95 splitting it into several subgoals;
    96 
    97 * Safe_tac: like safe_tac but uses the default claset;
    98 
    99 
   100 *** Simplifier ***
   101 
   102 * added simplification meta rules:
   103     (asm_)(full_)simplify: simpset -> thm -> thm;
   104 
   105 * simplifier.ML no longer part of Pure -- has to be loaded by object
   106 logics (again);
   107 
   108 * added prems argument to simplification procedures;
   109 
   110 * HOL, FOL, ZF: added infix function `addsplits':
   111   instead of `<simpset> setloop (split_tac <thms>)'
   112   you can simply write `<simpset> addsplits <thms>'
   113 
   114 
   115 *** Syntax ***
   116 
   117 * TYPE('a) syntax for type reflection terms;
   118 
   119 * no longer handles consts with name "" -- declare as 'syntax' instead;
   120 
   121 * pretty printer: changed order of mixfix annotation preference (again!);
   122 
   123 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
   124 
   125 
   126 *** HOL ***
   127 
   128 * HOL: there is a new splitter `split_asm_tac' that can be used e.g. 
   129   with `addloop' of the simplifier to faciliate case splitting in premises.
   130 
   131 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
   132 
   133 * HOL/Auth: new protocol proofs including some for the Internet
   134   protocol TLS;
   135 
   136 * HOL/Map: new theory of `maps' a la VDM;
   137 
   138 * HOL/simplifier: simplification procedures nat_cancel_sums for
   139 cancelling out common nat summands from =, <, <= (in)equalities, or
   140 differences; simplification procedures nat_cancel_factor for
   141 cancelling common factor from =, <, <= (in)equalities over natural
   142 sums; nat_cancel contains both kinds of procedures, it is installed by
   143 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
   144 
   145 * HOL/simplifier: terms of the form
   146   `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)'  (or t=x)
   147   are rewritten to
   148   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
   149   and those of the form
   150   `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)'  (or t=x)
   151   are rewritten to
   152   `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
   153 
   154 * HOL/datatype
   155   Each datatype `t' now comes with a theorem `split_t_case' of the form
   156 
   157   P(t_case f1 ... fn x) =
   158      ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
   159         ...
   160        (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
   161      )
   162 
   163   which can be added to a simpset via `addsplits'. The existing theorems
   164   expand_list_case and expand_option_case have been renamed to
   165   split_list_case and split_option_case.
   166 
   167   Additionally, there is a theorem `split_t_case_asm' of the form
   168 
   169   P(t_case f1 ... fn x) =
   170     ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
   171         ...
   172        (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
   173      )
   174 
   175   it be used with the new `split_asm_tac'.
   176 
   177 * HOL/Arithmetic:
   178   - `pred n' is automatically converted to `n-1'.
   179     Users are strongly encouraged not to use `pred' any longer,
   180     because it will disappear altogether at some point.
   181   - Users are strongly encouraged to write "0 < n" rather than
   182     "n ~= 0". Theorems and proof tools have been modified towards this
   183     `standard'.
   184 
   185 * HOL/Lists: the function "set_of_list" has been renamed "set"
   186   (and its theorems too);
   187 
   188 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
   189 
   190 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
   191   specialist theorems (like UN1_I) are gone.  Similarly for (INT x.B x);
   192 
   193 
   194 *** HOLCF ***
   195 
   196 * removed "axioms" and "generated by" sections;
   197 
   198 * replaced "ops" section by extended "consts" section, which is capable of
   199   handling the continuous function space "->" directly;
   200 
   201 * domain package:
   202   . proves theorems immediately and stores them in the theory,
   203   . creates hierachical name space,
   204   . now uses normal mixfix annotations (instead of cinfix...),
   205   . minor changes to some names and values (for consistency),
   206   . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
   207   . separator between mutual domain defs: changed "," to "and",
   208   . improved handling of sort constraints;  now they have to
   209     appear on the left-hand side of the equations only;
   210 
   211 * fixed LAM <x,y,zs>.b syntax;
   212 
   213 * added extended adm_tac to simplifier in HOLCF -- can now discharge
   214 adm (%x. P (t x)), where P is chainfinite and t continuous;
   215 
   216 
   217 *** FOL and ZF ***
   218 
   219 * FOL: there is a new splitter `split_asm_tac' that can be used e.g. 
   220   with `addloop' of the simplifier to faciliate case splitting in premises.
   221 
   222 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
   223 in HOL, they strip ALL and --> from proved theorems;
   224 
   225 
   226 
   227 New in Isabelle94-8 (May 1997)
   228 ------------------------------
   229 
   230 *** General Changes ***
   231 
   232 * new utilities to build / run / maintain Isabelle etc. (in parts
   233 still somewhat experimental); old Makefiles etc. still functional;
   234 
   235 * new 'Isabelle System Manual';
   236 
   237 * INSTALL text, together with ./configure and ./build scripts;
   238 
   239 * reimplemented type inference for greater efficiency, better error
   240 messages and clean internal interface;
   241 
   242 * prlim command for dealing with lots of subgoals (an easier way of
   243 setting goals_limit);
   244 
   245 
   246 *** Syntax ***
   247 
   248 * supports alternative (named) syntax tables (parser and pretty
   249 printer); internal interface is provided by add_modesyntax(_i);
   250 
   251 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
   252 be used in conjunction with the Isabelle symbol font; uses the
   253 "symbols" syntax table;
   254 
   255 * added token_translation interface (may translate name tokens in
   256 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
   257 the current print_mode); IMPORTANT: user print translation functions
   258 are responsible for marking newly introduced bounds
   259 (Syntax.mark_boundT);
   260 
   261 * token translations for modes "xterm" and "xterm_color" that display
   262 names in bold, underline etc. or colors (which requires a color
   263 version of xterm);
   264 
   265 * infixes may now be declared with names independent of their syntax;
   266 
   267 * added typed_print_translation (like print_translation, but may
   268 access type of constant);
   269 
   270 
   271 *** Classical Reasoner ***
   272 
   273 Blast_tac: a new tactic!  It is often more powerful than fast_tac, but has
   274 some limitations.  Blast_tac...
   275   + ignores addss, addbefore, addafter; this restriction is intrinsic
   276   + ignores elimination rules that don't have the correct format
   277 	(the conclusion MUST be a formula variable)
   278   + ignores types, which can make HOL proofs fail
   279   + rules must not require higher-order unification, e.g. apply_type in ZF
   280     [message "Function Var's argument not a bound variable" relates to this]
   281   + its proof strategy is more general but can actually be slower
   282 
   283 * substitution with equality assumptions no longer permutes other
   284 assumptions;
   285 
   286 * minor changes in semantics of addafter (now called addaltern); renamed
   287 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
   288 (and access functions for it);
   289 
   290 * improved combination of classical reasoner and simplifier: 
   291   + functions for handling clasimpsets
   292   + improvement of addss: now the simplifier is called _after_ the
   293     safe steps.
   294   + safe variant of addss called addSss: uses safe simplifications
   295     _during_ the safe steps. It is more complete as it allows multiple 
   296     instantiations of unknowns (e.g. with slow_tac).
   297 
   298 *** Simplifier ***
   299 
   300 * added interface for simplification procedures (functions that
   301 produce *proven* rewrite rules on the fly, depending on current
   302 redex);
   303 
   304 * ordering on terms as parameter (used for ordered rewriting);
   305 
   306 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
   307 
   308 * the solver is now split into a safe and an unsafe part.
   309 This should be invisible for the normal user, except that the
   310 functions setsolver and addsolver have been renamed to setSolver and
   311 addSolver; added safe_asm_full_simp_tac;
   312 
   313 
   314 *** HOL ***
   315 
   316 * a generic induction tactic `induct_tac' which works for all datatypes and
   317 also for type `nat';
   318 
   319 * a generic case distinction tactic `exhaust_tac' which works for all
   320 datatypes and also for type `nat';
   321 
   322 * each datatype comes with a function `size';
   323 
   324 * patterns in case expressions allow tuple patterns as arguments to
   325 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
   326 
   327 * primrec now also works with type nat;
   328 
   329 * recdef: a new declaration form, allows general recursive functions to be
   330 defined in theory files.  See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
   331 
   332 * the constant for negation has been renamed from "not" to "Not" to
   333 harmonize with FOL, ZF, LK, etc.;
   334 
   335 * HOL/ex/LFilter theory of a corecursive "filter" functional for
   336 infinite lists;
   337 
   338 * HOL/Modelcheck demonstrates invocation of model checker oracle;
   339 
   340 * HOL/ex/Ring.thy declares cring_simp, which solves equational
   341 problems in commutative rings, using axiomatic type classes for + and *;
   342 
   343 * more examples in HOL/MiniML and HOL/Auth;
   344 
   345 * more default rewrite rules for quantifiers, union/intersection;
   346 
   347 * a new constant `arbitrary == @x.False';
   348 
   349 * HOLCF/IOA replaces old HOL/IOA;
   350 
   351 * HOLCF changes: derived all rules and arities 
   352   + axiomatic type classes instead of classes 
   353   + typedef instead of faking type definitions
   354   + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
   355   + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
   356   + eliminated the types void, one, tr
   357   + use unit lift and bool lift (with translations) instead of one and tr
   358   + eliminated blift from Lift3.thy (use Def instead of blift)
   359   all eliminated rules are derived as theorems --> no visible changes ;
   360 
   361 
   362 *** ZF ***
   363 
   364 * ZF now has Fast_tac, Simp_tac and Auto_tac.  Union_iff is a now a default
   365 rewrite rule; this may affect some proofs.  eq_cs is gone but can be put back
   366 as ZF_cs addSIs [equalityI];
   367 
   368 
   369 
   370 New in Isabelle94-7 (November 96)
   371 ---------------------------------
   372 
   373 * allowing negative levels (as offsets) in prlev and choplev;
   374 
   375 * super-linear speedup for large simplifications;
   376 
   377 * FOL, ZF and HOL now use miniscoping: rewriting pushes
   378 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
   379 FAIL); can suppress it using the command Delsimps (ex_simps @
   380 all_simps); De Morgan laws are also now included, by default;
   381 
   382 * improved printing of ==>  :  ~:
   383 
   384 * new object-logic "Sequents" adds linear logic, while replacing LK
   385 and Modal (thanks to Sara Kalvala);
   386 
   387 * HOL/Auth: correctness proofs for authentication protocols;
   388 
   389 * HOL: new auto_tac combines rewriting and classical reasoning (many
   390 examples on HOL/Auth);
   391 
   392 * HOL: new command AddIffs for declaring theorems of the form P=Q to
   393 the rewriter and classical reasoner simultaneously;
   394 
   395 * function uresult no longer returns theorems in "standard" format;
   396 regain previous version by: val uresult = standard o uresult;
   397 
   398 
   399 
   400 New in Isabelle94-6
   401 -------------------
   402 
   403 * oracles -- these establish an interface between Isabelle and trusted
   404 external reasoners, which may deliver results as theorems;
   405 
   406 * proof objects (in particular record all uses of oracles);
   407 
   408 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
   409 
   410 * "constdefs" section in theory files;
   411 
   412 * "primrec" section (HOL) no longer requires names;
   413 
   414 * internal type "tactic" now simply "thm -> thm Sequence.seq";
   415 
   416 
   417 
   418 New in Isabelle94-5
   419 -------------------
   420 
   421 * reduced space requirements;
   422 
   423 * automatic HTML generation from theories;
   424 
   425 * theory files no longer require "..." (quotes) around most types;
   426 
   427 * new examples, including two proofs of the Church-Rosser theorem;
   428 
   429 * non-curried (1994) version of HOL is no longer distributed;
   430 
   431 
   432 
   433 New in Isabelle94-4
   434 -------------------
   435 
   436 * greatly reduced space requirements;
   437 
   438 * theory files (.thy) no longer require \...\ escapes at line breaks;
   439 
   440 * searchable theorem database (see the section "Retrieving theorems" on 
   441 page 8 of the Reference Manual);
   442 
   443 * new examples, including Grabczewski's monumental case study of the
   444 Axiom of Choice;
   445 
   446 * The previous version of HOL renamed to Old_HOL;
   447 
   448 * The new version of HOL (previously called CHOL) uses a curried syntax 
   449 for functions.  Application looks like f a b instead of f(a,b);
   450 
   451 * Mutually recursive inductive definitions finally work in HOL;
   452 
   453 * In ZF, pattern-matching on tuples is now available in all abstractions and
   454 translates to the operator "split";
   455 
   456 
   457 
   458 New in Isabelle94-3
   459 -------------------
   460 
   461 * new infix operator, addss, allowing the classical reasoner to 
   462 perform simplification at each step of its search.  Example:
   463 	fast_tac (cs addss ss)
   464 
   465 * a new logic, CHOL, the same as HOL, but with a curried syntax 
   466 for functions.  Application looks like f a b instead of f(a,b).  Also pairs 
   467 look like (a,b) instead of <a,b>;
   468 
   469 * PLEASE NOTE: CHOL will eventually replace HOL!
   470 
   471 * In CHOL, pattern-matching on tuples is now available in all abstractions.
   472 It translates to the operator "split".  A new theory of integers is available;
   473 
   474 * In ZF, integer numerals now denote two's-complement binary integers.
   475 Arithmetic operations can be performed by rewriting.  See ZF/ex/Bin.ML;
   476 
   477 * Many new examples: I/O automata, Church-Rosser theorem, equivalents 
   478 of the Axiom of Choice;
   479 
   480 
   481 
   482 New in Isabelle94-2
   483 -------------------
   484 
   485 * Significantly faster resolution;  
   486 
   487 * the different sections in a .thy file can now be mixed and repeated
   488 freely;
   489 
   490 * Database of theorems for FOL, HOL and ZF.  New
   491 commands including qed, qed_goal and bind_thm store theorems in the database.
   492 
   493 * Simple database queries: return a named theorem (get_thm) or all theorems of
   494 a given theory (thms_of), or find out what theory a theorem was proved in
   495 (theory_of_thm);
   496 
   497 * Bugs fixed in the inductive definition and datatype packages;
   498 
   499 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
   500 and HOL_dup_cs obsolete;
   501 
   502 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
   503 have been removed;
   504 
   505 * Simpler definition of function space in ZF;
   506 
   507 * new results about cardinal and ordinal arithmetic in ZF;
   508 
   509 * 'subtype' facility in HOL for introducing new types as subsets of existing
   510 types;
   511 
   512 
   513 $Id$