diff -r 6fe4200532b7 -r 7071b017cb35 src/HOLCF/CompactBasis.thy
--- a/src/HOLCF/CompactBasis.thy	Fri Jan 16 14:58:12 2009 +0100
+++ b/src/HOLCF/CompactBasis.thy	Fri Jan 16 14:58:56 2009 +0100
@@ -244,7 +244,7 @@
   assumes "ab_semigroup_idem_mult f"
   shows "fold_pd g f (PDPlus t u) = f (fold_pd g f t) (fold_pd g f u)"
 proof -
-  class_interpret ab_semigroup_idem_mult [f] by fact
+  interpret ab_semigroup_idem_mult f by fact
   show ?thesis unfolding fold_pd_def Rep_PDPlus by (simp add: image_Un fold1_Un2)
 qed