The Functor class is used for types that can be mapped over.



: Functor f => f a -> b -> f b

Replace all locations in the input (on the left) with the given value (on the right).


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

Map a function over a functor. Given a value as and a function f, as <&> f is f <$> as. That is, <&> is like <$> but the arguments are in reverse order.


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

Replace all the locations in the input with ().