diff -r 3d51fbf81c17 -r ebfe5ba905b0 NEWS
--- a/NEWS Fri Oct 05 21:52:39 2001 +0200
+++ b/NEWS Fri Oct 05 23:58:17 2001 +0200
@@ -33,6 +33,32 @@
*** HOL ***
+* HOL: moved over to sane numeral syntax; the new policy is as
+follows:
+
+ - 0 and 1 are polymorphic constants, which are defined on any
+ numeric type (nat, int, real etc.);
+
+ - 2, 3, 4, ... and -1, -2, -3, ... are polymorphic numerals, based
+ binary representation internally;
+
+ - type nat has special constructor Suc, and generally prefers Suc 0
+ over 1::nat and Suc (Suc 0) over 2::nat;
+
+This change may cause significant INCOMPATIBILITIES; here are some
+hints on converting existing sources:
+
+ - due to the new "num" token, "-0" and "-1" etc. are now atomic
+ entities, so expressions involving "-" (unary or binary minus) need
+ to be spaced properly;
+
+ - existing occurrences of "1" may need to be constraint "1::nat" or
+ even replaced by Suc 0; similar for old "2";
+
+ - replace "#nnn" by "nnn", and "#-nnn" by "-nnn";
+
+ - remove all special provisions on numerals in proofs;
+
* HOL: linorder_less_split superseded by linorder_cases;
* HOL: added "The" definite description operator; move Hilbert's "Eps"