Map +Data +base

Packages
base

map f xs is the list obtained by applying f to each element of xs, i.e., > map f [x1, x2, ..., xn] == [f x1, f x2, ..., f xn] > map f [x1, x2, ...] == [f x1, f x2, ...]

mapAccumL :: (acc -> x -> (acc, y)) -> acc -> [x] -> (acc, [y])

base Data.List

The mapAccumL function behaves like a combination of map and foldl; it applies a function to each element of a list, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new list.

mapAccumL :: Traversable t => (a -> b -> (a, c)) -> a -> t b -> (a, t c)

base Data.Traversable

The mapAccumL function behaves like a combination of fmap and foldl; it applies a function to each element of a structure, passing an accumulating parameter from left to right, and returning a final value of this accumulator together with the new structure.

mapAccumR :: (acc -> x -> (acc, y)) -> acc -> [x] -> (acc, [y])

base Data.List

The mapAccumR function behaves like a combination of map and foldr; it applies a function to each element of a list, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new list.

mapAccumR :: Traversable t => (a -> b -> (a, c)) -> a -> t b -> (a, t c)

base Data.Traversable

The mapAccumR function behaves like a combination of fmap and foldr; it applies a function to each element of a structure, passing an accumulating parameter from right to left, and returning a final value of this accumulator together with the new structure.

mapM :: (Traversable t, Monad m) => (a -> m b) -> t a -> m (t b)

base Data.Traversable

mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()

base Data.Foldable

Map each element of a structure to a monadic action, evaluate these actions from left to right, and ignore the results.

mapMaybe :: (a -> Maybe b) -> [a] -> [b]

base Data.Maybe

The mapMaybe function is a version of map which can throw out elements. In particular, the functional argument returns something of type Maybe b. If this is Nothing, no element is added on to the result list. If it just Just b, then b is included in the result list.

mappend :: Monoid a => a -> a -> a

base Data.Monoid

concatMap :: (a -> [b]) -> [a] -> [b]

base Prelude, base Data.List

Map a function over a list and concatenate the results.

fmap :: Functor f => (a -> b) -> f a -> f b

base Prelude, base Data.Functor, base Control.Monad, base Control.Monad.Instances

concatMap :: Foldable t => (a -> [b]) -> t a -> [b]

base Data.Foldable

Map a function over all the elements of a container and concatenate the resulting lists.

fmapDefault :: Traversable t => (a -> b) -> t a -> t b

base Data.Traversable