Sha256: 23ed7d6a03ebfe6fc8dde9ba16a9c0f602e16ce1f44bdeeba2e6371c931cd685
Contents?: true
Size: 908 Bytes
Versions: 396
Compression:
Stored size: 908 Bytes
Contents
module ListOps
( length
, reverse
, map
, filter
, foldr
, foldl'
, (++)
, concat
) where
import Prelude hiding
( length, reverse, map, filter, foldr, (++), concat )
foldl' :: (b -> a -> b) -> b -> [a] -> b
foldl' f = go
where
go acc [] = acc
go acc (x:xs) = let acc' = f acc x in acc' `seq` go acc' xs
{-# ANN foldr "HLint: ignore Use foldr" #-}
foldr :: (a -> b -> b) -> b -> [a] -> b
foldr f x0 = go
where
go [] = x0
go (x : xs) = x `f` go xs
length :: [a] -> Int
length = foldl' (\acc _ -> 1 + acc) 0
reverse :: [a] -> [a]
reverse = foldl' (flip (:)) []
map :: (a -> b) -> [a] -> [b]
map f = foldr (\x acc -> f x : acc) []
filter :: (a -> Bool) -> [a] -> [a]
filter f = foldr go []
where go x acc | f x = x : acc
| otherwise = acc
(++) :: [a] -> [a] -> [a]
xs ++ ys = foldr (:) ys xs
concat :: [[a]] -> [a]
concat = foldr (++) []
Version data entries
396 entries across 396 versions & 1 rubygems