diff -r f54a8a4134d3 -r e7ebe5554281 src/HOL/Enum.thy
--- a/src/HOL/Enum.thy	Sun Aug 31 09:10:41 2014 +0200
+++ b/src/HOL/Enum.thy	Sun Aug 31 09:10:42 2014 +0200
@@ -3,7 +3,7 @@
 header {* Finite types as explicit enumerations *}
 
 theory Enum
-imports Map
+imports Map Groups_List
 begin
 
 subsection {* Class @{text enum} *}