2 Isabelle NEWS -- history user-relevant changes
3 ==============================================
5 New in this Isabelle version
6 ----------------------------
8 *** Overview of INCOMPATIBILITIES (see below for more details) ***
10 * HOL: simplification of natural numbers is much changed; to partly
11 recover the old behaviour (e.g. to prevent n+n rewriting to #2*n)
12 issue the following ML commands:
14 Delsimprocs Nat_Numeral_Simprocs.cancel_numerals;
15 Delsimprocs [Nat_Numeral_Simprocs.combine_numerals];
17 * HOL: 0 is now overloaded, so the type constraint ::nat may sometimes be
20 * HOL: the constant for f``x is now "image" rather than "op ``";
22 * HOL: the disjoint sum is now "<+>" instead of "Plus"; the cartesian
23 product is now "<*>" instead of "Times"; the lexicographic product is
24 now "<*lex*>" instead of "**";
26 * HOL: exhaust_tac on datatypes superceded by new generic case_tac;
28 * HOL: simplification no longer dives into case-expressions
30 * HOL: the recursion equations generated by 'recdef' are now called
31 f.simps instead of f.rules;
33 * HOL: theory Sexp now in HOL/Induct examples (used to be part of main
34 HOL, but was unused); should better use HOL's datatype package anyway;
36 * HOL: removed obsolete theorem binding expand_if, use split_if instead;
38 * HOL/Real: "rabs" replaced by overloaded "abs" function;
40 * HOL/ML: even fewer consts are declared as global (see theories Ord,
41 Lfp, Gfp, WF); this only affects ML packages that refer to const names
44 * HOL, ZF: syntax for quotienting wrt an equivalence relation changed from
47 * Isar: changed syntax of local blocks from {{ }} to { };
49 * Isar/Provers: intro/elim/dest attributes: changed
50 intro/intro!/intro!! flags to intro!/intro/intro? (in most cases, one
51 should have to change intro!! to intro? only);
53 * Provers: strengthened force_tac by using new first_best_tac;
55 * Provers: Blast_tac now warns of and ignores "weak elimination rules" e.g.
56 [| inj ?f; ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
57 use instead the strong form,
58 [| inj ?f; ~ ?W ==> ?f ?x = ?f ?y; ?x = ?y ==> ?W |] ==> ?W
59 In HOL, FOL and ZF the function cla_make_elim will create such rules
62 * Provers: safe_asm_full_simp_tac is no longer in the simplifier signature. Use
63 val safe_asm_full_simp_tac = generic_simp_tac true (true,true,true);
66 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
67 timing flag supersedes proof_timing and Toplevel.trace;
69 * ML: PureThy.add_thms/add_axioms/add_defs return theorems as well;
71 * ML: PureThy.add_defs gets additional argument to indicate potential
72 overloading (usually false);
74 * LaTeX: several changes of isabelle.sty;
77 *** Document preparation ***
79 * formal comments (text blocks etc.) in new-style theories may now
80 contain antiquotations of thm/prop/term/typ to be presented according
81 to latex print mode; concrete syntax is like this: @{term[show_types]
84 * isatool mkdir provides easy setup of Isabelle session directories,
85 including proper document sources;
87 * generated LaTeX sources are now deleted after successful run
88 (isatool document -c); may retain a copy somewhere else via -D option
91 * isatool usedir -D now lets isatool latex -o sty update the Isabelle
92 style files, achieving self-contained LaTeX sources;
94 * old-style theories now produce (crude) LaTeX output as well;
96 * browser info session directories are now self-contained (may be put
97 on WWW server seperately); improved graphs of nested sessions; removed
98 graph for 'all sessions';
103 * Pure: local results and corresponding term bindings are now subject
104 to Hindley-Milner polymorphism (similar to ML); this accommodates
105 incremental type-inference nicely;
107 * Pure: new 'obtain' language element supports generalized existence
110 * Pure: new calculational elements 'moreover' and 'ultimately' support
111 plain accumulation of results, without applying any rules yet;
113 * Pure: scalable support for case-analysis type proofs: new 'case'
114 language element refers to local contexts symbolically, as produced by
115 certain proof methods; internally, case names are attached to theorems
118 * Pure: theory command 'hide' removes declarations from
119 class/type/const name spaces;
121 * Pure: theory command 'defs' supports option "(overloaded)" to
122 indicate potential overloading;
124 * Pure: changed syntax of local blocks from {{ }} to { };
126 * Pure: syntax of sorts made inner, i.e. have to write "{a, b, c}"
127 instead of {a, b, c};
129 * Pure now provides its own version of intro/elim/dest attributes;
130 useful for building new logics, but beware of confusion with the
131 Provers/classical ones;
133 * Pure: the local context of (non-atomic) goals is provided via case
136 * Pure: removed obsolete 'transfer' attribute (transfer of thms to the
137 current context is now done automatically);
139 * Pure: theory command 'method_setup' provides a simple interface for
140 definining proof methods in ML;
142 * Provers: splitter support (via 'split' attribute and 'simp' method
143 modifier); 'simp' method: 'only:' modifier removes loopers as well
146 * HOL: new proof method 'cases' and improved version of 'induct' now
147 support named cases; major packages (inductive, datatype, primrec,
148 recdef) support case names and properly name parameters;
150 * HOL: removed 'case_split' thm binding, should use 'cases' proof
153 * HOL/Calculation: new rules for substitution in inequalities
154 (monotonicity conditions are extracted to be proven terminally);
156 * HOL: removed obsolete expand_if = split_if; theorems if_splits =
157 split_if split_if_asm; datatype package provides theorems foo.splits =
158 foo.split foo.split_asm for each datatype;
160 * names of theorems etc. may be natural numbers as well;
162 * Provers: intro/elim/dest attributes: changed intro/intro!/intro!!
163 flags to intro!/intro/intro? (in most cases, one should have to change
164 intro!! to intro? only);
166 * 'pr' command: optional goals_limit argument; no longer prints theory
167 contexts, but only proof states;
169 * diagnostic commands 'pr', 'thm', 'prop', 'term', 'typ' admit
170 additional print modes to be specified; e.g. "pr(latex)" will print
171 proof state according to the Isabelle LaTeX style;
173 * improved support for emulating tactic scripts, including proof
174 methods 'tactic', 'res_inst_tac' etc., 'subgoal_tac', and 'case_tac' /
175 'induct_tac' (for HOL datatypes);
177 * simplified (more robust) goal selection of proof methods: 1st goal,
178 all goals, or explicit goal specifier (tactic emulation); thus 'proof
179 method scripts' have to be in depth-first order;
181 * tuned 'let' syntax: replaced 'as' keyword by 'and';
183 * removed 'help' command, which hasn't been too helpful anyway; should
184 instead use individual commands for printing items (print_commands,
187 * added 'nothing' --- the empty list of theorems;
192 * HOL/Prolog: a (bare-bones) implementation of Lambda-Prolog
194 * HOL/Algebra: new theory of rings and univariate polynomials, by
197 * HOL/record: fixed select-update simplification procedure to handle
198 extended records as well; admit "r" as field name;
200 * HOL/ex: new theory Factorization proving the Fundamental Theorem of
201 Arithmetic, by Thomas M Rasmussen;
203 * HOL/ex/Multiquote: multiple nested quotations and anti-quotations --
204 basically a generalized version of de-Bruijn representation; very
205 useful in avoiding lifting all operations;
207 * HOL/Real: "rabs" replaced by overloaded "abs" function;
209 * HOL: 0 is now overloaded over the new sort "zero", allowing its use with
210 other numeric types and also as the identity of groups, rings, etc.;
212 * HOL: new axclass plus_ac0 for addition with the AC-laws and 0 as identity.
213 Types nat and int belong to this axclass;
215 * greatly improved simplification involving numerals of type nat, int, real:
216 (i + #8 + j) = Suc k simplifies to #7 + (i + j) = k
217 i*j + k + j*#3*i simplifies to #4*(i*j) + k
218 two terms #m*u and #n*u are replaced by #(m+n)*u
219 (where #m, #n and u can implicitly be 1; this is simproc combine_numerals)
220 and the term/formula #m*u+x ~~ #n*u+y simplifies simplifies to #(m-n)+x ~~ y
221 or x ~~ #(n-m)+y, where ~~ is one of = < <= or - (simproc cancel_numerals);
223 * HOL: new version of "case_tac" subsumes both boolean case split and
224 "exhaust_tac" on datatypes; INCOMPATIBILITY: exhaust_tac no longer
225 exists, may define val exhaust_tac = case_tac for ad-hoc portability;
227 * HOL: simplification no longer dives into case-expressions: only the
228 selector expression is simplified, but not the remaining arms. To
229 enable full simplification of case-expressions for datatype t, you
230 need to remove t.weak_case_cong from the simpset, either permanently
231 (Delcongs[thm"t.weak_case_cong"];) or locally (delcongs [...]).
233 * HOL/recdef: the recursion equations generated by 'recdef' for
234 function 'f' are now called f.simps instead of f.rules; if all
235 termination conditions are proved automatically, these simplification
236 rules are added to the simpset, as in primrec; rules may be named
237 individually as well, resulting in a separate list of theorems for
240 * HOL/While is a new theory that provides a while-combinator. It permits the
241 definition of tail-recursive functions without the provision of a termination
242 measure. The latter is necessary once the invariant proof rule for while is
245 * HOL: new (overloaded) notation for the set of elements below/above some
246 element: {..u}, {..u(}, {l..}, {)l..}. See theory SetInterval.
248 * HOL: theorems impI, allI, ballI bound as "strip";
250 * theory Sexp now in HOL/Induct examples (used to be part of main HOL,
253 * fewer consts declared as global (e.g. have to refer to "Lfp.lfp"
254 instead of "lfp" internally; affects ML packages only);
256 * tuned AST representation of nested pairs, avoiding bogus output in
257 case of overlap with user translations (e.g. judgements over tuples);
262 * AddIffs now available, giving theorems of the form P<->Q to the
263 simplifier and classical reasoner simultaneously;
268 * AST translation rules no longer require constant head on LHS;
270 * improved name spaces: ambiguous output is qualified; support for
273 * compression of ML heaps images may now be controlled via -c option
274 of isabelle and isatool usedir (currently only observed by Poly/ML);
276 * provide TAGS file for Isabelle sources;
278 * ML: infix 'OF' is a version of 'MRS' with more appropriate argument
281 * ML: renamed flags Syntax.trace_norm_ast to Syntax.trace_ast; global
282 timing flag supersedes proof_timing and Toplevel.trace;
284 * ML: PureThy.add_defs gets additional argument to indicate potential
285 overloading (usually false);
287 * ML: new combinators |>> and |>>> for incremental transformations
288 with secondary results (e.g. certain theory extensions):
292 New in Isabelle99 (October 1999)
293 --------------------------------
295 *** Overview of INCOMPATIBILITIES (see below for more details) ***
297 * HOL: The THEN and ELSE parts of conditional expressions (if P then x else y)
298 are no longer simplified. (This allows the simplifier to unfold recursive
299 functional programs.) To restore the old behaviour, declare
301 Delcongs [if_weak_cong];
303 * HOL: Removed the obsolete syntax "Compl A"; use -A for set
306 * HOL: the predicate "inj" is now defined by translation to "inj_on";
308 * HOL/datatype: mutual_induct_tac no longer exists --
309 use induct_tac "x_1 ... x_n" instead of mutual_induct_tac ["x_1", ..., "x_n"]
311 * HOL/typedef: fixed type inference for representing set; type
312 arguments now have to occur explicitly on the rhs as type constraints;
314 * ZF: The con_defs part of an inductive definition may no longer refer
315 to constants declared in the same theory;
317 * HOL, ZF: the function mk_cases, generated by the inductive
318 definition package, has lost an argument. To simplify its result, it
319 uses the default simpset instead of a supplied list of theorems.
321 * HOL/List: the constructors of type list are now Nil and Cons;
323 * Simplifier: the type of the infix ML functions
324 setSSolver addSSolver setSolver addSolver
325 is now simpset * solver -> simpset where `solver' is a new abstract type
326 for packaging solvers. A solver is created via
327 mk_solver: string -> (thm list -> int -> tactic) -> solver
328 where the string argument is only a comment.
333 * Provers/Arith/fast_lin_arith.ML contains a functor for creating a
334 decision procedure for linear arithmetic. Currently it is used for
335 types `nat', `int', and `real' in HOL (see below); it can, should and
336 will be instantiated for other types and logics as well.
338 * The simplifier now accepts rewrite rules with flexible heads, eg
339 hom ?f ==> ?f(?x+?y) = ?f ?x + ?f ?y
340 They are applied like any rule with a non-pattern lhs, i.e. by first-order
346 * New Isabelle/Isar subsystem provides an alternative to traditional
347 tactical theorem proving; together with the ProofGeneral/isar user
348 interface it offers an interactive environment for developing human
349 readable proof documents (Isar == Intelligible semi-automated
350 reasoning); for further information see isatool doc isar-ref,
351 src/HOL/Isar_examples and http://isabelle.in.tum.de/Isar/
353 * improved presentation of theories: better HTML markup (including
354 colors), graph views in several sizes; isatool usedir now provides a
355 proper interface for user theories (via -P option); actual document
356 preparation based on (PDF)LaTeX is available as well (for new-style
357 theories only); see isatool doc system for more information;
359 * native support for Proof General, both for classic Isabelle and
362 * ML function thm_deps visualizes dependencies of theorems and lemmas,
363 using the graph browser tool;
365 * Isabelle manuals now also available as PDF;
367 * theory loader rewritten from scratch (may not be fully
368 bug-compatible); old loadpath variable has been replaced by show_path,
369 add_path, del_path, reset_path functions; new operations such as
370 update_thy, touch_thy, remove_thy, use/update_thy_only (see also
373 * improved isatool install: option -k creates KDE application icon,
374 option -p DIR installs standalone binaries;
376 * added ML_PLATFORM setting (useful for cross-platform installations);
377 more robust handling of platform specific ML images for SML/NJ;
379 * the settings environment is now statically scoped, i.e. it is never
380 created again in sub-processes invoked from isabelle, isatool, or
383 * path element specification '~~' refers to '$ISABELLE_HOME';
385 * in locales, the "assumes" and "defines" parts may be omitted if
388 * new print_mode "xsymbols" for extended symbol support (e.g. genuine
391 * new print_mode "HTML";
393 * new flag show_tags controls display of tags of theorems (which are
394 basically just comments that may be attached by some tools);
396 * Isamode 2.6 requires patch to accomodate change of Isabelle font
397 mode and goal output format:
399 diff -r Isamode-2.6/elisp/isa-load.el Isamode/elisp/isa-load.el
401 < (list (isa-getenv "ISABELLE") "-msymbols" logic-name)
403 > (list (isa-getenv "ISABELLE") "-misabelle_font" "-msymbols" logic-name)
404 diff -r Isabelle-2.6/elisp/isa-proofstate.el Isamode/elisp/isa-proofstate.el
406 < (defconst proofstate-proofstart-regexp "^Level [0-9]+$"
408 > (defconst proofstate-proofstart-regexp "^Level [0-9]+"
410 * function bind_thms stores lists of theorems (cf. bind_thm);
412 * new shorthand tactics ftac, eatac, datac, fatac;
414 * qed (and friends) now accept "" as result name; in that case the
415 theorem is not stored, but proper checks and presentation of the
418 * theorem database now also indexes constants "Trueprop", "all",
419 "==>", "=="; thus thms_containing, findI etc. may retrieve more rules;
426 * There are now decision procedures for linear arithmetic over nat and
429 1. arith_tac copes with arbitrary formulae involving `=', `<', `<=',
430 `+', `-', `Suc', `min', `max' and numerical constants; other subterms
431 are treated as atomic; subformulae not involving type `nat' or `int'
432 are ignored; quantified subformulae are ignored unless they are
433 positive universal or negative existential. The tactic has to be
434 invoked by hand and can be a little bit slow. In particular, the
435 running time is exponential in the number of occurrences of `min' and
436 `max', and `-' on `nat'.
438 2. fast_arith_tac is a cut-down version of arith_tac: it only takes
439 (negated) (in)equalities among the premises and the conclusion into
440 account (i.e. no compound formulae) and does not know about `min' and
441 `max', and `-' on `nat'. It is fast and is used automatically by the
444 NB: At the moment, these decision procedures do not cope with mixed
445 nat/int formulae where the two parts interact, such as `m < n ==>
448 * HOL/Numeral provides a generic theory of numerals (encoded
449 efficiently as bit strings); setup for types nat/int/real is in place;
450 INCOMPATIBILITY: since numeral syntax is now polymorphic, rather than
451 int, existing theories and proof scripts may require a few additional
454 * integer division and remainder can now be performed on constant
457 * many properties of integer multiplication, division and remainder
460 * An interface to the Stanford Validity Checker (SVC) is available through the
461 tactic svc_tac. Propositional tautologies and theorems of linear arithmetic
462 are proved automatically. SVC must be installed separately, and its results
463 must be TAKEN ON TRUST (Isabelle does not check the proofs, but tags any
464 invocation of the underlying oracle). For SVC see
465 http://verify.stanford.edu/SVC
467 * IsaMakefile: the HOL-Real target now builds an actual image;
472 * HOL/Real/HahnBanach: the Hahn-Banach theorem for real vector spaces
473 (in Isabelle/Isar) -- by Gertrud Bauer;
475 * HOL/BCV: generic model of bytecode verification, i.e. data-flow
476 analysis for assembly languages with subtypes;
478 * HOL/TLA (Lamport's Temporal Logic of Actions): major reorganization
479 -- avoids syntactic ambiguities and treats state, transition, and
480 temporal levels more uniformly; introduces INCOMPATIBILITIES due to
481 changed syntax and (many) tactics;
483 * HOL/inductive: Now also handles more general introduction rules such
484 as "ALL y. (y, x) : r --> y : acc r ==> x : acc r"; monotonicity
485 theorems are now maintained within the theory (maintained via the
488 * HOL/datatype: Now also handles arbitrarily branching datatypes
489 (using function types) such as
491 datatype 'a tree = Atom 'a | Branch "nat => 'a tree"
493 * HOL/record: record_simproc (part of the default simpset) takes care
494 of selectors applied to updated records; record_split_tac is no longer
495 part of the default claset; update_defs may now be removed from the
496 simpset in many cases; COMPATIBILITY: old behavior achieved by
498 claset_ref () := claset() addSWrapper record_split_wrapper;
499 Delsimprocs [record_simproc]
501 * HOL/typedef: fixed type inference for representing set; type
502 arguments now have to occur explicitly on the rhs as type constraints;
504 * HOL/recdef (TFL): 'congs' syntax now expects comma separated list of theorem
505 names rather than an ML expression;
507 * HOL/defer_recdef (TFL): like recdef but the well-founded relation can be
508 supplied later. Program schemes can be defined, such as
509 "While B C s = (if B s then While B C (C s) else s)"
510 where the well-founded relation can be chosen after B and C have been given.
512 * HOL/List: the constructors of type list are now Nil and Cons;
513 INCOMPATIBILITY: while [] and infix # syntax is still there, of
514 course, ML tools referring to List.list.op # etc. have to be adapted;
516 * HOL_quantifiers flag superseded by "HOL" print mode, which is
517 disabled by default; run isabelle with option -m HOL to get back to
518 the original Gordon/HOL-style output;
520 * HOL/Ord.thy: new bounded quantifier syntax (input only): ALL x<y. P,
521 ALL x<=y. P, EX x<y. P, EX x<=y. P;
523 * HOL basic syntax simplified (more orthogonal): all variants of
524 All/Ex now support plain / symbolic / HOL notation; plain syntax for
525 Eps operator is provided as well: "SOME x. P[x]";
527 * HOL/Sum.thy: sum_case has been moved to HOL/Datatype;
529 * HOL/Univ.thy: infix syntax <*>, <+>, <**>, <+> eliminated and made
530 thus available for user theories;
532 * HOLCF/IOA/Sequents: renamed 'Cons' to 'Consq' to avoid clash with
533 HOL/List; hardly an INCOMPATIBILITY since '>>' syntax is used all the
536 * HOL: new tactic smp_tac: int -> int -> tactic, which applies spec
537 several times and then mp;
542 * the notation <<...>> is now available as a notation for sequences of
545 * the simplifier is now installed
547 * the axiom system has been generalized (thanks to Soren Heilmann)
549 * the classical reasoner now has a default rule database
554 * new primrec section allows primitive recursive functions to be given
555 directly (as in HOL) over datatypes and the natural numbers;
557 * new tactics induct_tac and exhaust_tac for induction (or case
558 analysis) over datatypes and the natural numbers;
560 * the datatype declaration of type T now defines the recursor T_rec;
562 * simplification automatically does freeness reasoning for datatype
565 * automatic type-inference, with AddTCs command to insert new
568 * datatype introduction rules are now added as Safe Introduction rules
571 * the syntax "if P then x else y" is now available in addition to
575 *** Internal programming interfaces ***
577 * tuned simplifier trace output; new flag debug_simp;
579 * structures Vartab / Termtab (instances of TableFun) offer efficient
580 tables indexed by indexname_ord / term_ord (compatible with aconv);
582 * AxClass.axclass_tac lost the theory argument;
584 * tuned current_goals_markers semantics: begin / end goal avoids
585 printing empty lines;
587 * removed prs and prs_fn hook, which was broken because it did not
588 include \n in its semantics, forcing writeln to add one
589 uncoditionally; replaced prs_fn by writeln_fn; consider std_output:
590 string -> unit if you really want to output text without newline;
592 * Symbol.output subject to print mode; INCOMPATIBILITY: defaults to
593 plain output, interface builders may have to enable 'isabelle_font'
594 mode to get Isabelle font glyphs as before;
596 * refined token_translation interface; INCOMPATIBILITY: output length
597 now of type real instead of int;
599 * theory loader actions may be traced via new ThyInfo.add_hook
600 interface (see src/Pure/Thy/thy_info.ML); example application: keep
601 your own database of information attached to *whole* theories -- as
602 opposed to intra-theory data slots offered via TheoryDataFun;
604 * proper handling of dangling sort hypotheses (at last!);
605 Thm.strip_shyps and Drule.strip_shyps_warning take care of removing
606 extra sort hypotheses that can be witnessed from the type signature;
607 the force_strip_shyps flag is gone, any remaining shyps are simply
608 left in the theorem (with a warning issued by strip_shyps_warning);
612 New in Isabelle98-1 (October 1998)
613 ----------------------------------
615 *** Overview of INCOMPATIBILITIES (see below for more details) ***
617 * several changes of automated proof tools;
619 * HOL: major changes to the inductive and datatype packages, including
620 some minor incompatibilities of theory syntax;
622 * HOL: renamed r^-1 to 'converse' from 'inverse'; 'inj_onto' is now
625 * HOL: removed duplicate thms in Arith:
626 less_imp_add_less should be replaced by trans_less_add1
627 le_imp_add_le should be replaced by trans_le_add1
629 * HOL: unary minus is now overloaded (new type constraints may be
632 * HOL and ZF: unary minus for integers is now #- instead of #~. In
633 ZF, expressions such as n#-1 must be changed to n#- 1, since #-1 is
634 now taken as an integer constant.
636 * Pure: ML function 'theory_of' renamed to 'theory';
642 1. Asm_full_simp_tac is now more aggressive.
643 1. It will sometimes reorient premises if that increases their power to
645 2. It does no longer proceed strictly from left to right but may also
646 rotate premises to achieve further simplification.
647 For compatibility reasons there is now Asm_lr_simp_tac which is like the
648 old Asm_full_simp_tac in that it does not rotate premises.
649 2. The simplifier now knows a little bit about nat-arithmetic.
651 * Classical reasoner: wrapper mechanism for the classical reasoner now
652 allows for selected deletion of wrappers, by introduction of names for
653 wrapper functionals. This implies that addbefore, addSbefore,
654 addaltern, and addSaltern now take a pair (name, tactic) as argument,
655 and that adding two tactics with the same name overwrites the first
656 one (emitting a warning).
657 type wrapper = (int -> tactic) -> (int -> tactic)
658 setWrapper, setSWrapper, compWrapper and compSWrapper are replaced by
659 addWrapper, addSWrapper: claset * (string * wrapper) -> claset
660 delWrapper, delSWrapper: claset * string -> claset
661 getWrapper is renamed to appWrappers, getSWrapper to appSWrappers;
663 * Classical reasoner: addbefore/addSbefore now have APPEND/ORELSE
664 semantics; addbefore now affects only the unsafe part of step_tac
665 etc.; this affects addss/auto_tac/force_tac, so EXISTING PROOFS MAY
666 FAIL, but proofs should be fixable easily, e.g. by replacing Auto_tac
669 * Classical reasoner: setwrapper to setWrapper and compwrapper to
670 compWrapper; added safe wrapper (and access functions for it);
672 * HOL/split_all_tac is now much faster and fails if there is nothing
673 to split. Some EXISTING PROOFS MAY REQUIRE ADAPTION because the order
674 and the names of the automatically generated variables have changed.
675 split_all_tac has moved within claset() from unsafe wrappers to safe
676 wrappers, which means that !!-bound variables are split much more
677 aggressively, and safe_tac and clarify_tac now split such variables.
678 If this splitting is not appropriate, use delSWrapper "split_all_tac".
679 Note: the same holds for record_split_tac, which does the job of
680 split_all_tac for record fields.
682 * HOL/Simplifier: Rewrite rules for case distinctions can now be added
683 permanently to the default simpset using Addsplits just like
684 Addsimps. They can be removed via Delsplits just like
685 Delsimps. Lower-case versions are also available.
687 * HOL/Simplifier: The rule split_if is now part of the default
688 simpset. This means that the simplifier will eliminate all occurrences
689 of if-then-else in the conclusion of a goal. To prevent this, you can
690 either remove split_if completely from the default simpset by
691 `Delsplits [split_if]' or remove it in a specific call of the
692 simplifier using `... delsplits [split_if]'. You can also add/delete
693 other case splitting rules to/from the default simpset: every datatype
694 generates suitable rules `split_t_case' and `split_t_case_asm' (where
695 t is the name of the datatype).
697 * Classical reasoner / Simplifier combination: new force_tac (and
698 derivatives Force_tac, force) combines rewriting and classical
699 reasoning (and whatever other tools) similarly to auto_tac, but is
700 aimed to solve the given subgoal completely.
705 * new top-level commands `Goal' and `Goalw' that improve upon `goal'
706 and `goalw': the theory is no longer needed as an explicit argument -
707 the current theory context is used; assumptions are no longer returned
708 at the ML-level unless one of them starts with ==> or !!; it is
709 recommended to convert to these new commands using isatool fixgoal
710 (backup your sources first!);
712 * new top-level commands 'thm' and 'thms' for retrieving theorems from
713 the current theory context, and 'theory' to lookup stored theories;
715 * new theory section 'locale' for declaring constants, assumptions and
716 definitions that have local scope;
718 * new theory section 'nonterminals' for purely syntactic types;
720 * new theory section 'setup' for generic ML setup functions
721 (e.g. package initialization);
723 * the distribution now includes Isabelle icons: see
724 lib/logo/isabelle-{small,tiny}.xpm;
726 * isatool install - install binaries with absolute references to
729 * isatool logo -- create instances of the Isabelle logo (as EPS);
731 * print mode 'emacs' reserved for Isamode;
733 * support multiple print (ast) translations per constant name;
735 * theorems involving oracles are now printed with a suffixed [!];
740 * there is now a tutorial on Isabelle/HOL (do 'isatool doc tutorial');
742 * HOL/inductive package reorganized and improved: now supports mutual
748 oddI "n : EVEN ==> Suc n : ODD"
749 evenI "n : ODD ==> Suc n : EVEN"
751 new theorem list "elims" contains an elimination rule for each of the
752 recursive sets; inductive definitions now handle disjunctive premises
755 INCOMPATIBILITIES: requires Inductive as an ancestor; component
756 "mutual_induct" no longer exists - the induction rule is always
757 contained in "induct";
760 * HOL/datatype package re-implemented and greatly improved: now
761 supports mutually recursive datatypes such as
764 'a aexp = IF_THEN_ELSE ('a bexp) ('a aexp) ('a aexp)
765 | SUM ('a aexp) ('a aexp)
766 | DIFF ('a aexp) ('a aexp)
769 'a bexp = LESS ('a aexp) ('a aexp)
770 | AND ('a bexp) ('a bexp)
771 | OR ('a bexp) ('a bexp)
773 as well as indirectly recursive datatypes such as
776 ('a, 'b) term = Var 'a
777 | App 'b ((('a, 'b) term) list)
779 The new tactic mutual_induct_tac [<var_1>, ..., <var_n>] i performs
780 induction on mutually / indirectly recursive datatypes.
782 Primrec equations are now stored in theory and can be accessed via
783 <function_name>.simps.
787 - Theories using datatypes must now have theory Datatype as an
789 - The specific <typename>.induct_tac no longer exists - use the
790 generic induct_tac instead.
791 - natE has been renamed to nat.exhaust - use exhaust_tac
792 instead of res_inst_tac ... natE. Note that the variable
793 names in nat.exhaust differ from the names in natE, this
794 may cause some "fragile" proofs to fail.
795 - The theorems split_<typename>_case and split_<typename>_case_asm
796 have been renamed to <typename>.split and <typename>.split_asm.
797 - Since default sorts of type variables are now handled correctly,
798 some datatype definitions may have to be annotated with explicit
800 - Primrec definitions no longer require function name and type
801 of recursive argument.
803 Consider using isatool fixdatatype to adapt your theories and proof
804 scripts to the new package (backup your sources first!).
807 * HOL/record package: considerably improved implementation; now
808 includes concrete syntax for record types, terms, updates; theorems
809 for surjective pairing and splitting !!-bound record variables; proof
810 support is as follows:
812 1) standard conversions (selectors or updates applied to record
813 constructor terms) are part of the standard simpset;
815 2) inject equations of the form ((x, y) = (x', y')) == x=x' & y=y' are
816 made part of standard simpset and claset via addIffs;
818 3) a tactic for record field splitting (record_split_tac) is part of
819 the standard claset (addSWrapper);
821 To get a better idea about these rules you may retrieve them via
822 something like 'thms "foo.simps"' or 'thms "foo.iffs"', where "foo" is
823 the name of your record type.
825 The split tactic 3) conceptually simplifies by the following rule:
827 "(!!x. PROP ?P x) == (!!a b. PROP ?P (a, b))"
829 Thus any record variable that is bound by meta-all will automatically
830 blow up into some record constructor term, consequently the
831 simplifications of 1), 2) apply. Thus force_tac, auto_tac etc. shall
832 solve record problems automatically.
835 * reorganized the main HOL image: HOL/Integ and String loaded by
836 default; theory Main includes everything;
838 * automatic simplification of integer sums and comparisons, using cancellation;
840 * added option_map_eq_Some and not_Some_eq to the default simpset and claset;
842 * added disj_not1 = "(~P | Q) = (P --> Q)" to the default simpset;
844 * many new identities for unions, intersections, set difference, etc.;
846 * expand_if, expand_split, expand_sum_case and expand_nat_case are now
847 called split_if, split_split, split_sum_case and split_nat_case (to go
850 * HOL/Prod introduces simplification procedure unit_eq_proc rewriting
851 (?x::unit) = (); this is made part of the default simpset, which COULD
852 MAKE EXISTING PROOFS FAIL under rare circumstances (consider
853 'Delsimprocs [unit_eq_proc];' as last resort); also note that
854 unit_abs_eta_conv is added in order to counter the effect of
855 unit_eq_proc on (%u::unit. f u), replacing it by f rather than by
858 * HOL/Fun INCOMPATIBILITY: `inj_onto' is now called `inj_on' (which
861 * HOL/Set INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
862 It and 'sym RS equals0D' are now in the default claset, giving automatic
863 disjointness reasoning but breaking a few old proofs.
865 * HOL/Relation INCOMPATIBILITY: renamed the relational operator r^-1
866 to 'converse' from 'inverse' (for compatibility with ZF and some
869 * HOL/recdef can now declare non-recursive functions, with {} supplied as
870 the well-founded relation;
872 * HOL/Set INCOMPATIBILITY: the complement of set A is now written -A instead of
873 Compl A. The "Compl" syntax remains available as input syntax for this
876 * HOL/Update: new theory of function updates:
877 f(a:=b) == %x. if x=a then b else f x
878 may also be iterated as in f(a:=b,c:=d,...);
880 * HOL/Vimage: new theory for inverse image of a function, syntax f-``B;
883 - new function list_update written xs[i:=v] that updates the i-th
884 list position. May also be iterated as in xs[i:=a,j:=b,...].
885 - new function `upt' written [i..j(] which generates the list
886 [i,i+1,...,j-1], i.e. the upper bound is excluded. To include the upper
887 bound write [i..j], which is a shorthand for [i..j+1(].
888 - new lexicographic orderings and corresponding wellfoundedness theorems.
891 - removed 'pred' (predecessor) function;
892 - generalized some theorems about n-1;
893 - many new laws about "div" and "mod";
894 - new laws about greatest common divisors (see theory ex/Primes);
896 * HOL/Relation: renamed the relational operator r^-1 "converse"
897 instead of "inverse";
899 * HOL/Induct/Multiset: a theory of multisets, including the wellfoundedness
900 of the multiset ordering;
902 * directory HOL/Real: a construction of the reals using Dedekind cuts
903 (not included by default);
905 * directory HOL/UNITY: Chandy and Misra's UNITY formalism;
907 * directory HOL/Hoare: a new version of Hoare logic which permits many-sorted
908 programs, i.e. different program variables may have different types.
910 * calling (stac rew i) now fails if "rew" has no effect on the goal
911 [previously, this check worked only if the rewrite rule was unconditional]
912 Now rew can involve either definitions or equalities (either == or =).
917 * theory Main includes everything; INCOMPATIBILITY: theory ZF.thy contains
918 only the theorems proved on ZF.ML;
920 * ZF INCOMPATIBILITY: rule `equals0D' is now a well-formed destruct rule;
921 It and 'sym RS equals0D' are now in the default claset, giving automatic
922 disjointness reasoning but breaking a few old proofs.
924 * ZF/Update: new theory of function updates
925 with default rewrite rule f(x:=y) ` z = if(z=x, y, f`z)
926 may also be iterated as in f(a:=b,c:=d,...);
928 * in let x=t in u(x), neither t nor u(x) has to be an FOL term.
930 * calling (stac rew i) now fails if "rew" has no effect on the goal
931 [previously, this check worked only if the rewrite rule was unconditional]
932 Now rew can involve either definitions or equalities (either == or =).
934 * case_tac provided for compatibility with HOL
935 (like the old excluded_middle_tac, but with subgoals swapped)
938 *** Internal programming interfaces ***
940 * Pure: several new basic modules made available for general use, see
941 also src/Pure/README;
943 * improved the theory data mechanism to support encapsulation (data
944 kind name replaced by private Object.kind, acting as authorization
945 key); new type-safe user interface via functor TheoryDataFun; generic
946 print_data function becomes basically useless;
948 * removed global_names compatibility flag -- all theory declarations
949 are qualified by default;
951 * module Pure/Syntax now offers quote / antiquote translation
952 functions (useful for Hoare logic etc. with implicit dependencies);
953 see HOL/ex/Antiquote for an example use;
955 * Simplifier now offers conversions (asm_)(full_)rewrite: simpset ->
958 * new tactical CHANGED_GOAL for checking that a tactic modifies a
961 * Display.print_goals function moved to Locale.print_goals;
963 * standard print function for goals supports current_goals_markers
964 variable for marking begin of proof, end of proof, start of goal; the
965 default is ("", "", ""); setting current_goals_markers := ("<proof>",
966 "</proof>", "<goal>") causes SGML like tagged proof state printing,
971 New in Isabelle98 (January 1998)
972 --------------------------------
974 *** Overview of INCOMPATIBILITIES (see below for more details) ***
976 * changed lexical syntax of terms / types: dots made part of long
977 identifiers, e.g. "%x.x" no longer possible, should be "%x. x";
979 * simpset (and claset) reference variable replaced by functions
980 simpset / simpset_ref;
982 * no longer supports theory aliases (via merge) and non-trivial
983 implicit merge of thms' signatures;
985 * most internal names of constants changed due to qualified names;
987 * changed Pure/Sequence interface (see Pure/seq.ML);
990 *** General Changes ***
992 * hierachically structured name spaces (for consts, types, axms, thms
993 etc.); new lexical class 'longid' (e.g. Foo.bar.x) may render much of
994 old input syntactically incorrect (e.g. "%x.x"); COMPATIBILITY:
995 isatool fixdots ensures space after dots (e.g. "%x. x"); set
996 long_names for fully qualified output names; NOTE: ML programs
997 (special tactics, packages etc.) referring to internal names may have
998 to be adapted to cope with fully qualified names; in case of severe
999 backward campatibility problems try setting 'global_names' at compile
1000 time to have enrything declared within a flat name space; one may also
1001 fine tune name declarations in theories via the 'global' and 'local'
1004 * reimplemented the implicit simpset and claset using the new anytype
1005 data filed in signatures; references simpset:simpset ref etc. are
1006 replaced by functions simpset:unit->simpset and
1007 simpset_ref:unit->simpset ref; COMPATIBILITY: use isatool fixclasimp
1008 to patch your ML files accordingly;
1010 * HTML output now includes theory graph data for display with Java
1011 applet or isatool browser; data generated automatically via isatool
1012 usedir (see -i option, ISABELLE_USEDIR_OPTIONS);
1014 * defs may now be conditional; improved rewrite_goals_tac to handle
1015 conditional equations;
1017 * defs now admits additional type arguments, using TYPE('a) syntax;
1019 * theory aliases via merge (e.g. M=A+B+C) no longer supported, always
1020 creates a new theory node; implicit merge of thms' signatures is
1021 restricted to 'trivial' ones; COMPATIBILITY: one may have to use
1022 transfer:theory->thm->thm in (rare) cases;
1024 * improved handling of draft signatures / theories; draft thms (and
1025 ctyps, cterms) are automatically promoted to real ones;
1027 * slightly changed interfaces for oracles: admit many per theory, named
1028 (e.g. oracle foo = mlfun), additional name argument for invoke_oracle;
1030 * print_goals: optional output of const types (set show_consts and
1033 * improved output of warnings (###) and errors (***);
1035 * subgoal_tac displays a warning if the new subgoal has type variables;
1037 * removed old README and Makefiles;
1039 * replaced print_goals_ref hook by print_current_goals_fn and result_error_fn;
1041 * removed obsolete init_pps and init_database;
1043 * deleted the obsolete tactical STATE, which was declared by
1044 fun STATE tacfun st = tacfun st st;
1046 * cd and use now support path variables, e.g. $ISABELLE_HOME, or ~
1047 (which abbreviates $HOME);
1049 * changed Pure/Sequence interface (see Pure/seq.ML); COMPATIBILITY:
1050 use isatool fixseq to adapt your ML programs (this works for fully
1051 qualified references to the Sequence structure only!);
1053 * use_thy no longer requires writable current directory; it always
1054 reloads .ML *and* .thy file, if either one is out of date;
1057 *** Classical Reasoner ***
1059 * Clarify_tac, clarify_tac, clarify_step_tac, Clarify_step_tac: new
1060 tactics that use classical reasoning to simplify a subgoal without
1061 splitting it into several subgoals;
1063 * Safe_tac: like safe_tac but uses the default claset;
1068 * added simplification meta rules:
1069 (asm_)(full_)simplify: simpset -> thm -> thm;
1071 * simplifier.ML no longer part of Pure -- has to be loaded by object
1074 * added prems argument to simplification procedures;
1076 * HOL, FOL, ZF: added infix function `addsplits':
1077 instead of `<simpset> setloop (split_tac <thms>)'
1078 you can simply write `<simpset> addsplits <thms>'
1083 * TYPE('a) syntax for type reflection terms;
1085 * no longer handles consts with name "" -- declare as 'syntax' instead;
1087 * pretty printer: changed order of mixfix annotation preference (again!);
1089 * Pure: fixed idt/idts vs. pttrn/pttrns syntactic categories;
1094 * HOL: there is a new splitter `split_asm_tac' that can be used e.g.
1095 with `addloop' of the simplifier to faciliate case splitting in premises.
1097 * HOL/TLA: Stephan Merz's formalization of Lamport's Temporal Logic of Actions;
1099 * HOL/Auth: new protocol proofs including some for the Internet
1102 * HOL/Map: new theory of `maps' a la VDM;
1104 * HOL/simplifier: simplification procedures nat_cancel_sums for
1105 cancelling out common nat summands from =, <, <= (in)equalities, or
1106 differences; simplification procedures nat_cancel_factor for
1107 cancelling common factor from =, <, <= (in)equalities over natural
1108 sums; nat_cancel contains both kinds of procedures, it is installed by
1109 default in Arith.thy -- this COULD MAKE EXISTING PROOFS FAIL;
1111 * HOL/simplifier: terms of the form
1112 `? x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x)' (or t=x)
1114 `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t)',
1115 and those of the form
1116 `! x. P1(x) & ... & Pn(x) & x=t & Q1(x) & ... Qn(x) --> R(x)' (or t=x)
1118 `P1(t) & ... & Pn(t) & Q1(t) & ... Qn(t) --> R(t)',
1121 Each datatype `t' now comes with a theorem `split_t_case' of the form
1123 P(t_case f1 ... fn x) =
1124 ( (!y1 ... ym1. x = C1 y1 ... ym1 --> P(f1 y1 ... ym1)) &
1126 (!y1 ... ymn. x = Cn y1 ... ymn --> P(f1 y1 ... ymn))
1129 and a theorem `split_t_case_asm' of the form
1131 P(t_case f1 ... fn x) =
1132 ~( (? y1 ... ym1. x = C1 y1 ... ym1 & ~P(f1 y1 ... ym1)) |
1134 (? y1 ... ymn. x = Cn y1 ... ymn & ~P(f1 y1 ... ymn))
1136 which can be added to a simpset via `addsplits'. The existing theorems
1137 expand_list_case and expand_option_case have been renamed to
1138 split_list_case and split_option_case.
1141 - `pred n' is automatically converted to `n-1'.
1142 Users are strongly encouraged not to use `pred' any longer,
1143 because it will disappear altogether at some point.
1144 - Users are strongly encouraged to write "0 < n" rather than
1145 "n ~= 0". Theorems and proof tools have been modified towards this
1149 the function "set_of_list" has been renamed "set" (and its theorems too);
1150 the function "nth" now takes its arguments in the reverse order and
1151 has acquired the infix notation "!" as in "xs!n".
1153 * HOL/Set: UNIV is now a constant and is no longer translated to Compl{};
1155 * HOL/Set: The operator (UN x.B x) now abbreviates (UN x:UNIV. B x) and its
1156 specialist theorems (like UN1_I) are gone. Similarly for (INT x.B x);
1158 * HOL/record: extensible records with schematic structural subtyping
1159 (single inheritance); EXPERIMENTAL version demonstrating the encoding,
1160 still lacks various theorems and concrete record syntax;
1165 * removed "axioms" and "generated by" sections;
1167 * replaced "ops" section by extended "consts" section, which is capable of
1168 handling the continuous function space "->" directly;
1171 . proves theorems immediately and stores them in the theory,
1172 . creates hierachical name space,
1173 . now uses normal mixfix annotations (instead of cinfix...),
1174 . minor changes to some names and values (for consistency),
1175 . e.g. cases -> casedist, dists_eq -> dist_eqs, [take_lemma] -> take_lemmas,
1176 . separator between mutual domain defs: changed "," to "and",
1177 . improved handling of sort constraints; now they have to
1178 appear on the left-hand side of the equations only;
1180 * fixed LAM <x,y,zs>.b syntax;
1182 * added extended adm_tac to simplifier in HOLCF -- can now discharge
1183 adm (%x. P (t x)), where P is chainfinite and t continuous;
1188 * FOL: there is a new splitter `split_asm_tac' that can be used e.g.
1189 with `addloop' of the simplifier to faciliate case splitting in premises.
1191 * qed_spec_mp, qed_goal_spec_mp, qed_goalw_spec_mp are available, as
1192 in HOL, they strip ALL and --> from proved theorems;
1196 New in Isabelle94-8 (May 1997)
1197 ------------------------------
1199 *** General Changes ***
1201 * new utilities to build / run / maintain Isabelle etc. (in parts
1202 still somewhat experimental); old Makefiles etc. still functional;
1204 * new 'Isabelle System Manual';
1206 * INSTALL text, together with ./configure and ./build scripts;
1208 * reimplemented type inference for greater efficiency, better error
1209 messages and clean internal interface;
1211 * prlim command for dealing with lots of subgoals (an easier way of
1212 setting goals_limit);
1217 * supports alternative (named) syntax tables (parser and pretty
1218 printer); internal interface is provided by add_modesyntax(_i);
1220 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
1221 be used in conjunction with the Isabelle symbol font; uses the
1222 "symbols" syntax table;
1224 * added token_translation interface (may translate name tokens in
1225 arbitrary ways, dependent on their type (free, bound, tfree, ...) and
1226 the current print_mode); IMPORTANT: user print translation functions
1227 are responsible for marking newly introduced bounds
1228 (Syntax.mark_boundT);
1230 * token translations for modes "xterm" and "xterm_color" that display
1231 names in bold, underline etc. or colors (which requires a color
1234 * infixes may now be declared with names independent of their syntax;
1236 * added typed_print_translation (like print_translation, but may
1237 access type of constant);
1240 *** Classical Reasoner ***
1242 Blast_tac: a new tactic! It is often more powerful than fast_tac, but has
1243 some limitations. Blast_tac...
1244 + ignores addss, addbefore, addafter; this restriction is intrinsic
1245 + ignores elimination rules that don't have the correct format
1246 (the conclusion MUST be a formula variable)
1247 + ignores types, which can make HOL proofs fail
1248 + rules must not require higher-order unification, e.g. apply_type in ZF
1249 [message "Function Var's argument not a bound variable" relates to this]
1250 + its proof strategy is more general but can actually be slower
1252 * substitution with equality assumptions no longer permutes other
1255 * minor changes in semantics of addafter (now called addaltern); renamed
1256 setwrapper to setWrapper and compwrapper to compWrapper; added safe wrapper
1257 (and access functions for it);
1259 * improved combination of classical reasoner and simplifier:
1260 + functions for handling clasimpsets
1261 + improvement of addss: now the simplifier is called _after_ the
1263 + safe variant of addss called addSss: uses safe simplifications
1264 _during_ the safe steps. It is more complete as it allows multiple
1265 instantiations of unknowns (e.g. with slow_tac).
1269 * added interface for simplification procedures (functions that
1270 produce *proven* rewrite rules on the fly, depending on current
1273 * ordering on terms as parameter (used for ordered rewriting);
1275 * new functions delcongs, deleqcongs, and Delcongs. richer rep_ss;
1277 * the solver is now split into a safe and an unsafe part.
1278 This should be invisible for the normal user, except that the
1279 functions setsolver and addsolver have been renamed to setSolver and
1280 addSolver; added safe_asm_full_simp_tac;
1285 * a generic induction tactic `induct_tac' which works for all datatypes and
1286 also for type `nat';
1288 * a generic case distinction tactic `exhaust_tac' which works for all
1289 datatypes and also for type `nat';
1291 * each datatype comes with a function `size';
1293 * patterns in case expressions allow tuple patterns as arguments to
1294 constructors, for example `case x of [] => ... | (x,y,z)#ps => ...';
1296 * primrec now also works with type nat;
1298 * recdef: a new declaration form, allows general recursive functions to be
1299 defined in theory files. See HOL/ex/Fib, HOL/ex/Primes, HOL/Subst/Unify.
1301 * the constant for negation has been renamed from "not" to "Not" to
1302 harmonize with FOL, ZF, LK, etc.;
1304 * HOL/ex/LFilter theory of a corecursive "filter" functional for
1307 * HOL/Modelcheck demonstrates invocation of model checker oracle;
1309 * HOL/ex/Ring.thy declares cring_simp, which solves equational
1310 problems in commutative rings, using axiomatic type classes for + and *;
1312 * more examples in HOL/MiniML and HOL/Auth;
1314 * more default rewrite rules for quantifiers, union/intersection;
1316 * a new constant `arbitrary == @x.False';
1318 * HOLCF/IOA replaces old HOL/IOA;
1320 * HOLCF changes: derived all rules and arities
1321 + axiomatic type classes instead of classes
1322 + typedef instead of faking type definitions
1323 + eliminated the internal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
1324 + new axclasses cpo, chfin, flat with flat < chfin < pcpo < cpo < po
1325 + eliminated the types void, one, tr
1326 + use unit lift and bool lift (with translations) instead of one and tr
1327 + eliminated blift from Lift3.thy (use Def instead of blift)
1328 all eliminated rules are derived as theorems --> no visible changes ;
1333 * ZF now has Fast_tac, Simp_tac and Auto_tac. Union_iff is a now a default
1334 rewrite rule; this may affect some proofs. eq_cs is gone but can be put back
1335 as ZF_cs addSIs [equalityI];
1339 New in Isabelle94-7 (November 96)
1340 ---------------------------------
1342 * allowing negative levels (as offsets) in prlev and choplev;
1344 * super-linear speedup for large simplifications;
1346 * FOL, ZF and HOL now use miniscoping: rewriting pushes
1347 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
1348 FAIL); can suppress it using the command Delsimps (ex_simps @
1349 all_simps); De Morgan laws are also now included, by default;
1351 * improved printing of ==> : ~:
1353 * new object-logic "Sequents" adds linear logic, while replacing LK
1354 and Modal (thanks to Sara Kalvala);
1356 * HOL/Auth: correctness proofs for authentication protocols;
1358 * HOL: new auto_tac combines rewriting and classical reasoning (many
1359 examples on HOL/Auth);
1361 * HOL: new command AddIffs for declaring theorems of the form P=Q to
1362 the rewriter and classical reasoner simultaneously;
1364 * function uresult no longer returns theorems in "standard" format;
1365 regain previous version by: val uresult = standard o uresult;
1372 * oracles -- these establish an interface between Isabelle and trusted
1373 external reasoners, which may deliver results as theorems;
1375 * proof objects (in particular record all uses of oracles);
1377 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
1379 * "constdefs" section in theory files;
1381 * "primrec" section (HOL) no longer requires names;
1383 * internal type "tactic" now simply "thm -> thm Sequence.seq";
1390 * reduced space requirements;
1392 * automatic HTML generation from theories;
1394 * theory files no longer require "..." (quotes) around most types;
1396 * new examples, including two proofs of the Church-Rosser theorem;
1398 * non-curried (1994) version of HOL is no longer distributed;
1405 * greatly reduced space requirements;
1407 * theory files (.thy) no longer require \...\ escapes at line breaks;
1409 * searchable theorem database (see the section "Retrieving theorems" on
1410 page 8 of the Reference Manual);
1412 * new examples, including Grabczewski's monumental case study of the
1415 * The previous version of HOL renamed to Old_HOL;
1417 * The new version of HOL (previously called CHOL) uses a curried syntax
1418 for functions. Application looks like f a b instead of f(a,b);
1420 * Mutually recursive inductive definitions finally work in HOL;
1422 * In ZF, pattern-matching on tuples is now available in all abstractions and
1423 translates to the operator "split";
1430 * new infix operator, addss, allowing the classical reasoner to
1431 perform simplification at each step of its search. Example:
1432 fast_tac (cs addss ss)
1434 * a new logic, CHOL, the same as HOL, but with a curried syntax
1435 for functions. Application looks like f a b instead of f(a,b). Also pairs
1436 look like (a,b) instead of <a,b>;
1438 * PLEASE NOTE: CHOL will eventually replace HOL!
1440 * In CHOL, pattern-matching on tuples is now available in all abstractions.
1441 It translates to the operator "split". A new theory of integers is available;
1443 * In ZF, integer numerals now denote two's-complement binary integers.
1444 Arithmetic operations can be performed by rewriting. See ZF/ex/Bin.ML;
1446 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
1447 of the Axiom of Choice;
1454 * Significantly faster resolution;
1456 * the different sections in a .thy file can now be mixed and repeated
1459 * Database of theorems for FOL, HOL and ZF. New
1460 commands including qed, qed_goal and bind_thm store theorems in the database.
1462 * Simple database queries: return a named theorem (get_thm) or all theorems of
1463 a given theory (thms_of), or find out what theory a theorem was proved in
1466 * Bugs fixed in the inductive definition and datatype packages;
1468 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
1469 and HOL_dup_cs obsolete;
1471 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
1474 * Simpler definition of function space in ZF;
1476 * new results about cardinal and ordinal arithmetic in ZF;
1478 * 'subtype' facility in HOL for introducing new types as subsets of existing