intersectionWith f m1 m2
= intersectionWithKey (\k x y -> f x y) m1 m2
-- | /O(n+m)/. Intersection with a combining function.
-- Intersection is more efficient on (bigset `intersection` smallset)
intersectionWith f m1 m2
= intersectionWithKey (\k x y -> f x y) m1 m2
-- | /O(n+m)/. Intersection with a combining function.
-- Intersection is more efficient on (bigset `intersection` smallset)