-- | /O(n+m)/. Is this a proper submap? (ie. a submap but not equal).
-- Defined as (@'isProperSubmapOf' = 'isProperSubmapOfBy' (==)@).
isProperSubmapOf :: Eq a => IntMap a -> IntMap a -> Bool
isProperSubmapOf (IntMap m1) (IntMap m2) = W.isProperSubmapOf m1 m2
isProperSubmapOf :: Eq a => IntMap a -> IntMap a -> Bool
isProperSubmapOf (IntMap m1) (IntMap m2) = W.isProperSubmapOf m1 m2
isProperSubmapOf (IntMap m1) (IntMap m2) = W.isProperSubmapOf m1 m2