MHask-0.3.0.0: The category of monads

MHask.Functor

Description

Compare to base.Prelude.Functor (Functor)

Synopsis

class Functor t whereSource

Functor is its own dual.

Methods

fmap :: (Monad m, Monad n) => (m ~> n) -> t m ~> t nSource

Flipping the arrows on fmap's type signature is just the same type signature in disguise.

(m <~ n) -> (t m <~ t n)

Instances