YusukeHosonuma
/ map_filter.hs
Created
May 8, 2016 13:19
Haskell - implement map and filter functions by recursion and foldr versions.
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| -- | recursion version | |
| map' :: (a -> b) -> [a] -> [b] | |
| map' _ [] = [] | |
| map' f (x:xs) = f x : map' f xs | |
| filter' :: (a -> Bool) -> [a] -> [a] | |
| filter' _ [] = [] | |
| filter' f (x:xs) | |
| | f x = x : (filter' f xs) |