--- a/src/HOL/Transitive_Closure.thy Fri Sep 18 07:54:26 2009 +0200
+++ b/src/HOL/Transitive_Closure.thy Fri Sep 18 09:07:48 2009 +0200
@@ -77,7 +77,7 @@
subsection {* Reflexive-transitive closure *}
lemma reflcl_set_eq [pred_set_conv]: "(sup (\<lambda>x y. (x, y) \<in> r) op =) = (\<lambda>x y. (x, y) \<in> r Un Id)"
- by (simp add: expand_fun_eq)
+ by (simp add: expand_fun_eq sup2_iff)
lemma r_into_rtrancl [intro]: "!!p. p \<in> r ==> p \<in> r^*"
-- {* @{text rtrancl} of @{text r} contains @{text r} *}