2 Isabelle NEWS -- history of user-visible changes
3 ================================================
5 New in Isabelle94-8 (really-soon-now 1997 FIXME)
6 ------------------------------------------------
8 * HOLCF changes: derived all rules and arities
9 + axiomatic type classes instead of classes
10 + typedef instead of faking type definitions
11 + eliminated the initernal constants less_fun, less_cfun, UU_fun, UU_cfun etc.
12 + new axclasses cpo,chfin,flat with flat<chfin<pcpo<cpo<po
13 + eliminated the types void, one, tr
14 + use unit lift and bool lift (with translations) instead of one and tr
15 + eliminated blift from Lift3.thy (use Def instead of blift)
16 all eliminated rules are derivd as theorems --> no visible changes
18 * simplifier: new functions delcongs, deleqcongs, and Delcongs. richer rep_ss.
20 * simplifier: the solver is now split into a safe and an unsafe part.
21 This should be invisible for the normal user, except that the functions
22 setsolver and addsolver have been renamed to setSolver and addSolver.
23 added safe_asm_full_simp_tac.
25 * classical reasoner: little changes in semantics of addafter (now: addaltern),
26 renamed setwrapper to setWrapper, addwrapper to addWrapper
27 added safe wrapper (and access functions for it)
29 * improved combination of classical reasoner and simplifier:
30 new addss, auto_tac, functions for handling clasimpsets, ...
31 Now, the simplification is safe (therefore moved to safe_step_tac) and thus
32 more complete, as multiple instantiation of unknowns (with slow_tac) possible
33 COULD MAKE EXISTING PROOFS FAIL; in case of problems with unstable old proofs:
34 use unsafe_addss and unsafe_auto_tac
36 * HOL: primrec now also works with type nat;
38 * new utilities to build / run / maintain Isabelle etc. (in parts
39 still somewhat experimental); old Makefiles etc. still functional;
41 * simplifier: termless order as parameter; added interface for
42 simplification procedures (functions that produce *proven* rewrite
43 rules on the fly, depending on current redex);
45 * now supports alternative (named) syntax tables (parser and pretty
46 printer); internal interface is provided by add_modesyntax(_i);
48 * Pure, FOL, ZF, HOL, HOLCF now support symbolic input and output; to
49 be used in conjunction with the isabelle symbol font; uses the
50 "symbols" syntax table;
52 * infixes may now be declared with names independent of their syntax;
54 * added typed_print_translation (like print_translation, but may
55 access type of constant);
57 * prlim command for dealing with lots of subgoals (an easier way of
60 * HOL/ex/Ring.thy declares cring_simp, which solves equational
61 problems in commutative rings, using axiomatic type classes for + and *;
63 * ZF now has Fast_tac, Simp_tac and Auto_tac. WARNING: don't use
64 ZF.thy anymore! Contains fewer defs and could make a bogus simpset.
65 Beware of Union_iff. eq_cs is gone, can be put back as ZF_cs addSIs
68 * more examples in HOL/MiniML and HOL/Auth;
70 * more default rewrite rules in HOL for quantifiers, union/intersection;
75 New in Isabelle94-7 (November 96)
76 ---------------------------------
78 * allowing negative levels (as offsets) in prlev and choplev;
80 * super-linear speedup for large simplifications;
82 * FOL, ZF and HOL now use miniscoping: rewriting pushes
83 quantifications in as far as possible (COULD MAKE EXISTING PROOFS
84 FAIL); can suppress it using the command Delsimps (ex_simps @
85 all_simps); De Morgan laws are also now included, by default;
87 * improved printing of ==> : ~:
89 * new object-logic "Sequents" adds linear logic, while replacing LK
90 and Modal (thanks to Sara Kalvala);
92 * HOL/Auth: correctness proofs for authentication protocols;
94 * HOL: new auto_tac combines rewriting and classical reasoning (many
95 examples on HOL/Auth);
97 * HOL: new command AddIffs for declaring theorems of the form P=Q to
98 the rewriter and classical reasoner simultaneously;
100 * function uresult no longer returns theorems in "standard" format;
101 regain previous version by: val uresult = standard o uresult;
108 * oracles -- these establish an interface between Isabelle and trusted
109 external reasoners, which may deliver results as theorems;
111 * proof objects (in particular record all uses of oracles);
113 * Simp_tac, Fast_tac, etc. that refer to implicit simpset / claset;
115 * "constdefs" section in theory files;
117 * "primrec" section (HOL) no longer requires names;
119 * internal type "tactic" now simply "thm -> thm Sequence.seq";
126 * reduced space requirements;
128 * automatic HTML generation from theories;
130 * theory files no longer require "..." (quotes) around most types;
132 * new examples, including two proofs of the Church-Rosser theorem;
134 * non-curried (1994) version of HOL is no longer distributed;
141 * greatly space requirements;
143 * theory files (.thy) no longer require \...\ escapes at line breaks;
145 * searchable theorem database (see the section "Retrieving theorems" on
146 page 8 of the Reference Manual);
148 * new examples, including Grabczewski's monumental case study of the
151 * The previous version of HOL renamed to Old_HOL;
153 * The new version of HOL (previously called CHOL) uses a curried syntax
154 for functions. Application looks like f a b instead of f(a,b);
156 * Mutually recursive inductive definitions finally work in HOL;
158 * In ZF, pattern-matching on tuples is now available in all abstractions and
159 translates to the operator "split";
166 * new infix operator, addss, allowing the classical reasoner to
167 perform simplification at each step of its search. Example:
168 fast_tac (cs addss ss)
170 * a new logic, CHOL, the same as HOL, but with a curried syntax
171 for functions. Application looks like f a b instead of f(a,b). Also pairs
172 look like (a,b) instead of <a,b>;
174 * PLEASE NOTE: CHOL will eventually replace HOL!
176 * In CHOL, pattern-matching on tuples is now available in all abstractions.
177 It translates to the operator "split". A new theory of integers is available;
179 * In ZF, integer numerals now denote two's-complement binary integers.
180 Arithmetic operations can be performed by rewriting. See ZF/ex/Bin.ML;
182 * Many new examples: I/O automata, Church-Rosser theorem, equivalents
183 of the Axiom of Choice;
190 * Significantly faster resolution;
192 * the different sections in a .thy file can now be mixed and repeated
195 * Database of theorems for FOL, HOL and ZF. New
196 commands including qed, qed_goal and bind_thm store theorems in the database.
198 * Simple database queries: return a named theorem (get_thm) or all theorems of
199 a given theory (thms_of), or find out what theory a theorem was proved in
202 * Bugs fixed in the inductive definition and datatype packages;
204 * The classical reasoner provides deepen_tac and depth_tac, making FOL_dup_cs
205 and HOL_dup_cs obsolete;
207 * Syntactic ambiguities caused by the new treatment of syntax in Isabelle94-1
210 * Simpler definition of function space in ZF;
212 * new results about cardinal and ordinal arithmetic in ZF;
214 * 'subtype' facility in HOL for introducing new types as subsets of existing