On 9/13/06, Bertram Felgenhauer [EMAIL PROTECTED] wrote:
Michael Shulman wrote:
class MonadList m where
option :: [a] - m a
[...]
There's no need for an extra class, it can be done with MonadPlus:
option :: MonadPlus m = [a] - m a
option = msum . map return
But this doesn't always give
Michael Shulman wrote:
The frequent occurence of ListT $ return in my code when I use the ListT
monad transformer has made me wonder why there isn't a standard typeclass
`MonadList', like those for the other monad transformers, encapsulating
the essence of being a list-like monad -- in this
