Haskell Map Implementation with Foldr

myMap.hs

-- Problem 1: Redefine Haskell's map using foldr from the standard prelude

module MyMap where

map'            :: (a -> b) -> [a] -> [b]
map' f []       = []
map' f (x:xs)   = foldr (\y ys -> (f y):ys) [] xs