diff -r 8361d7a517b4 -r b5260f5272a4 src/HOL/Algebra/Bij.thy
--- a/src/HOL/Algebra/Bij.thy	Mon Jun 22 08:17:52 2009 +0200
+++ b/src/HOL/Algebra/Bij.thy	Mon Jun 22 20:59:12 2009 +0200
@@ -50,7 +50,7 @@
     apply (simp add: compose_Bij)
    apply (simp add: id_Bij)
   apply (simp add: compose_Bij)
-  apply (blast intro: compose_assoc [symmetric] Bij_imp_funcset)
+  apply (blast intro: compose_assoc [symmetric] dest: Bij_imp_funcset)
  apply (simp add: id_Bij Bij_imp_funcset Bij_imp_extensional, simp)
 apply (blast intro: Bij_compose_restrict_eq restrict_Inv_Bij)
 done