diff -r 42af8ae6e2c1 -r f04da668581c src/HOL/Fun.thy
--- a/src/HOL/Fun.thy	Tue Feb 24 10:44:53 1998 +0100
+++ b/src/HOL/Fun.thy	Tue Feb 24 11:35:33 1998 +0100
@@ -6,7 +6,7 @@
 Notions about functions.
 *)
 
-Fun = Set +
+Fun = Vimage +
 
 instance set :: (term) order
                        (subset_refl,subset_trans,subset_antisym,psubset_eq)