+lookupUniqSet :: Uniquable a => UniqSet a -> a -> Maybe a
+lookupUniqSet (MkUniqSet set) x = lookupUFM set x
+
+elemUniqSet_Directly :: Unique -> UniqSet a -> Bool
+elemUniqSet_Directly x (MkUniqSet set) = maybeToBool (lookupUFM_Directly set x)
+
+sizeUniqSet :: UniqSet a -> Int
+sizeUniqSet (MkUniqSet set) = sizeUFM set
+
+hashUniqSet :: UniqSet a -> Int
+hashUniqSet (MkUniqSet set) = hashUFM set
+