\\

(\\) :: Eq a => [a] -> [a] -> [a]
base Data.List
The \\ function is list difference ((non-associative). In the result of xs \\ ys, the first occurrence of each element of ys in turn (if any) has been removed from xs. Thus > (xs ++ ys) \\ xs == ys. It is a special case of deleteFirstsBy, which allows the programmer to supply their own equality test.
(\\) :: IntMap a -> IntMap b -> IntMap a
containers Data.IntMap.Strict, containers Data.IntMap.Lazy
Same as difference.
(\\) :: IntSet -> IntSet -> IntSet
containers Data.IntSet
O(n+m). See difference.
(\\) :: Ord a => Set a -> Set a -> Set a
containers Data.Set
O(n+m). See difference.
(\\) :: Ord k => Map k a -> Map k b -> Map k a
containers Data.Map.Lazy, containers Data.Map.Strict
Same as difference.