filter -package:Cabal -package:containers is:exact

filter, applied to a predicate and a list, returns the list of those elements that satisfy the predicate; i.e.,

filter p xs = [ x | x <- xs, p x]

>>> filter odd [1, 2, 3]
[1,3]

filter :: (a -> Bool) -> NonEmpty a -> [a]

filter p xs removes any elements from xs that do not satisfy p.

filter :: (Word8 -> Bool) -> ByteString -> ByteString

O(n) filter, applied to a predicate and a ByteString, returns a ByteString containing those characters that satisfy the predicate.

filter :: (Char -> Bool) -> ByteString -> ByteString

O(n) filter, applied to a predicate and a ByteString, returns a ByteString containing those characters that satisfy the predicate.

filter :: (Word8 -> Bool) -> ShortByteString -> ShortByteString

O(n) filter, applied to a predicate and a ByteString, returns a ByteString containing those characters that satisfy the predicate.

filter :: (Char -> Bool) -> Text -> Text

O(n) filter, applied to a predicate and a Text, returns a Text containing those characters that satisfy the predicate.

filter :: (Char -> Bool) -> Stream Char -> Stream Char

O(n) filter, applied to a predicate and a stream, returns a stream containing those characters that satisfy the predicate. Properties

unstream . filter p . stream = filter p

filter :: (a -> Bool) -> Vector a -> Vector a

O(n) Drop all elements that do not satisfy the predicate.

filter :: (a -> Bool) -> Bundle v a -> Bundle v a

Drop elements which do not satisfy the predicate

filter :: Monad m => (a -> Bool) -> Bundle m v a -> Bundle m v a

Drop elements which do not satisfy the predicate

filter :: Vector v a => (a -> Bool) -> v a -> v a

O(n) Drop all elements that do not satisfy the predicate.

filter :: Prim a => (a -> Bool) -> Vector a -> Vector a

O(n) Drop all elements that do not satisfy the predicate.

filter :: Storable a => (a -> Bool) -> Vector a -> Vector a

O(n) Drop all elements that do not satisfy the predicate.

filter :: Unbox a => (a -> Bool) -> Vector a -> Vector a

O(n) Drop all elements that do not satisfy the predicate.

filter :: (v -> Bool) -> HashMap k v -> HashMap k v

Filter this map by retaining only elements which values satisfy a predicate.

filter :: (a -> Bool) -> HashSet a -> HashSet a

Filter this set by retaining only elements satisfying a predicate.