is there union and intersect Haskell Prelude implementation?

Question

Is there in the Standard Prelude functions which implement the union and the intersection of sets ?

union      :: (Eq a) => [a] -> [a] -> [a]
inters         


        

Answer 1

The base library provides list versions, as camccann points out. If you want something a bit more efficient, consider Data.Set, which provides:

union :: Ord a => Set a -> Set a -> Set a

intersection :: Ord a => Set a -> Set a -> Set a

with complexity O(n+m).