[Haskell-cafe] Confusion on the third monad law when using lambda abstractions

[Dan Piponi]

On Wed, Jun 17, 2009 at 6:08 PM, Jon Strait<jstrait at moonloop.net> wrote:
> ...but if there
> were another monad defined like,
>
> data MadMaybe a = Nothing | Perhaps | Just a

MadMaybe violates the second law. It's quite unlike a monad.
--
Dan