universum-1.0.0: Custom prelude used in Serokell
Universum.Functor.Fmap
Synopsis
map :: Functor f => (a -> b) -> f a -> f b Source #
map generalized to Functor.
map
Functor
(<<$>>) :: (Functor f, Functor g) => (a -> b) -> f (g a) -> f (g b) infixl 4 Source #
Alias for fmap . fmap. Convenient to work with two nested Functors.
fmap . fmap
>>> negate <<$>> Just [1,2,3] Just [-1,-2,-3]
>>>
negate <<$>> Just [1,2,3]