--- a/src/Pure/Isar/class.ML Tue Aug 14 23:23:00 2007 +0200
+++ b/src/Pure/Isar/class.ML Tue Aug 14 23:23:04 2007 +0200
@@ -617,7 +617,7 @@
in
-val instance_sort_cmd = gen_instance_sort Sign.read_class Sign.read_sort;
+val instance_sort_cmd = gen_instance_sort Sign.read_class Syntax.global_read_sort;
val instance_sort = gen_instance_sort Sign.certify_class Sign.certify_sort;
val prove_instance_sort = instance_sort' o prove_interpretation_in;
val instance_class_cmd = gen_instance_class Sign.read_class;