--- a/src/Tools/Metis/src/ElementSet.sig Wed Jun 08 08:47:43 2011 +0200
+++ b/src/Tools/Metis/src/ElementSet.sig Wed Jun 08 08:47:43 2011 +0200
@@ -131,6 +131,14 @@
val disjoint : set -> set -> bool
(* ------------------------------------------------------------------------- *)
+(* Closing under an operation. *)
+(* ------------------------------------------------------------------------- *)
+
+val closedAdd : (element -> set) -> set -> set -> set
+
+val close : (element -> set) -> set -> set
+
+(* ------------------------------------------------------------------------- *)
(* Converting to and from lists. *)
(* ------------------------------------------------------------------------- *)