diff -r de7792ea4090 -r b7c394c7a619 NEWS
--- a/NEWS	Tue Mar 10 16:12:35 2015 +0000
+++ b/NEWS	Mon Mar 16 15:30:00 2015 +0000
@@ -80,6 +80,12 @@
   type, so in particular on "real" and "complex" uniformly.
   Minor INCOMPATIBILITY: type constraints may be needed.
 
+* The factorial function, "fact", now has type "nat => 'a" (of a sort that admits
+  numeric types including nat, int, real and complex. INCOMPATIBILITY:
+  an expression such as "fact 3 = 6" may require a type constraint, and the combination
+  "real (fact k)" is likely to be unsatisfactory. If a type conversion is still necessary,
+  then use "of_nat (fact k)".
+
 * removed functions "natfloor" and "natceiling",
   use "nat o floor" and "nat o ceiling" instead.
   A few of the lemmas have been retained and adapted: in their names