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A comment on Functors, Applicatives, and Monads in Pictures (2013). Parent comment

Re:Functors, Applicatives, and Monads in Pictures (2013) by rane on Thursday September 24, 2015 @07:18PM (#10275461)
Isn't Maybe being an instance of Applicative enough in this case?
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Re:Functors, Applicatives, and Monads in Pictures (2013) by AnimalMuppet on Thursday September 24, 2015 @07:48PM (#10275591)
Maybe...

But seriously, I guess I think it's not a Monad. The Monad signature (in this case) is

  (>>=) :: Maybe a -> (a -> Maybe b) -> Maybe b
and I think what we really want (and what I said we wanted to do) is

  Maybe a -> (a -> b) -> Maybe b
I don't know whether that's Applicative or Functor, but I don't think it's Monad.
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Re:Functors, Applicatives, and Monads in Pictures (2013) by Muphrid on Saturday September 26, 2015 @06:20PM (#10284627)
That operation is called fmap, and it's characteristic of a functor. In Haskell, it's called liftM for monads, but they're really the same thing (and I think recent proposals are going to iron out this redundancy). fmap is one of the properties of a functor. All monads are functors, so all monads provide an operation with that signature.
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