AW: Newbie qustion about monads

Juanma Barranquero jmbarranquero at
Thu Oct 2 15:25:41 EDT 2003

On Thu, 2 Oct 2003 13:16:13 +0200 
Markus.Schnell at wrote:

> The Monad class is just called Monad because it is intended
> to cover a monad. But it doesn't ensure the laws. That is your
> sole responsibility.

Yeah, I know. But it's difficult to ensure I'm satisfying the laws when
I'm not entirely sure what do they ask from me...

> You can define it to your liking as long as it is commutative.

Ah, that's what I was expecting. So, in both my examples, defining:

  instance Eq MyMonad where
      MM _ x == MM _ y = x == y

would suffice and the first law would be satisfied.



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