MonadTrans MaybeT |
MonadReader r m => MonadReader r (MaybeT m) |
MonadState s m => MonadState s (MaybeT m) |
(Monoid w, MonadWriter w m) => MonadWriter w (MaybeT m) |
Functor m => Functor (MaybeT m) |
Monad m => Monad (MaybeT m) |
MonadIO m => MonadIO (MaybeT m) |
Monad m => MonadPlus (MaybeT m) |