On 3/13/07, Taral <[EMAIL PROTECTED]> wrote:
This is closer, but still doesn't work:

And this works, and I don't know why:

class MonadTrans' i o where
   lift' :: (Monad i, Monad o) => i a -> o a

instance Monad m => MonadTrans' m m where
   lift' = id

instance (MonadTrans t, Monad b, MonadTrans' a b) => MonadTrans' a (t b) where
   lift' = lift . lift'

Help?

--
Taral <[EMAIL PROTECTED]>
"You can't prove anything."
   -- Gödel's Incompetence Theorem
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