Re: [Haskell-cafe] better way to do this?

On Mon, Oct 05, 2009 at 07:24:00AM -0700, Michael Mossey wrote:

If I understand correctly, this works because IO is an instance of Applicative, correct?

I wonder if any of the random monads are instances of Applicative.

If they aren't then that's a bug in the library :). Every monad can be made an instance of Applicative; given any monad M, instance Functor M where fmap = liftM -- from Control.Monad instance Applicative M where pure = return (<*>) = ap -- from Control.Applicative -- Felipe.