> "Cont (Endo b) a" is the usual backtracking monad.
It is? Would you say more about that? A pointer would be fine. I'm wondering what the role of Endo is here.
Cheers, - Conal
On 9/9/07, David Menendez <zednenem@psualum.com> wrote:
On 9/8/07, Conal Elliott <conal@conal.net> wrote:
> I'd like to see the following addition to Control.Monad.Cont in mtl:
>
> instance Monoid r => Monoid (Cont r a) where
> mempty = Cont mempty
> m `mappend` m' = Cont (runCont m `mappend` runCont m')
Alternatively,
instance Monoid r => MonadPlus (Cont r a) where
mzero = Cont mempty
mplus a b = Cont $ runCont a `mappend` runCont b
"Cont (Endo b) a" is the usual backtracking monad.