--- a/src/HOL/Arith.thy Tue May 23 18:19:06 2000 +0200
+++ b/src/HOL/Arith.thy Tue May 23 18:21:51 2000 +0200
@@ -26,9 +26,8 @@
mult_0 "0 * n = 0"
mult_Suc "Suc m * n = n + (m * n)"
-(*We overload the constant for all + types, but unfortunately there's no
- overloaded 0...*)
-consts sum_below :: [nat=>'a, nat] => ('a::plus)
+(*We overload the constant for all + types*)
+consts sum_below :: "[nat=>'a, nat] => ('a::{zero,plus})"
primrec
sum_below_0 "sum_below f 0 = 0"
sum_below_Suc "sum_below f (Suc n) = f(n) + sum_below f n"