shithub: MicroHs

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Add foldl' and foldr'

--- a/lib/Data/List.hs

+++ b/lib/Data/List.hs

@@ -86,6 +86,12 @@

     rec (x : xs) = f x (rec xs)

   in rec

+foldr' :: forall a b . (a -> b -> b) -> b -> [a] -> b

+foldr' f z [] = z

+foldr' f z (x:xs) =

+  let y = foldr f z xs

+  in  y `seq` f x y

+

 foldr1 :: forall a . (a -> a -> a) -> [a] -> a

 foldr1 _ [] = error "foldr1"

 foldr1 f (x : xs) = foldr f x xs

@@ -93,6 +99,12 @@

 foldl :: forall a b . (b -> a -> b) -> b -> [a] -> b

 foldl _ z [] = z

 foldl f z (x : xs) = foldl f (f z x) xs

+

+foldl' :: forall a b . (b -> a -> b) -> b -> [a] -> b

+foldl' _ z [] = z

+foldl' f z (x : xs) =

+  let y = f z x

+  in  y `seq` foldl f y xs

 foldl1 :: forall a . (a -> a -> a) -> [a] -> a

 foldl1 _ [] = error "foldl1"

-- 

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