On 31/12/2011 13:18, Yves Parès wrote:
But still, I maintain my previous view. I could clarify that by saying
that (e.g. for Maybe) we could separate it in two types, Maybe itself
and its monad:
-- The plain Maybe type
data Maybe a = Just a | Nothing
-- The MaybeMonad
newtype MaybeMonad a = MM ( () -> Maybe a )
You've just reminded me of a painful time - lot's a scratching my head
and saying "but these parser functions are monadic - the tutorial
clearly says they're monadic - why does my every attempt at making the
type an instance of Monad fail?"
Answer - I only had the equivalent of the Maybe type, and I was trying
to force it where the MaybeMonad should go.
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