sets.extras: few more words.

diff --git a/extra/sets/extras/extras.factor b/extra/sets/extras/extras.factor
index 0a5132b3790be689d15fd366f4afa8d5101aab05..323db086b68ff8c09c438f1b11460fb7a6833f5d 100644 (file)
--- a/extra/sets/extras/extras.factor
+++ b/extra/sets/extras/extras.factor
@@ -11,3 +11,9 @@ IN: sets.extras
 
 : proper-subset? ( set1 set2 -- ? )
     2dup subset? [ swap subset? not ] [ 2drop f ] if ;
+
+: superset? ( set1 set2 -- ? )
+    swap subset? ;
+
+: disjoint? ( set1 set2 -- ? )
+    intersects? not ;