[Haskell-beginners] (no subject)

I wanted to run the map function from Data.Map, let's call it M.map, but inside a monad transformer stack including the Error monad. M.map has this type: M.map :: (Ord k) => (a -> b) -> Map k a -> Map k b However, I want to use a mapping function that has type (Monad m) => a -> m b (i.e. errors could be thrown during the computation, a log could be written, etc) I wrote the following. Any comments on this way of doing things? mapMapM :: (Monad m, Ord k) => (a -> m b) -> Map k a -> m (Map k b) mapMapM g mapIn = do let h (k,a) = do b <- g a return (k,b) y <- mapM h (M.toAscList mapIn) return $ M.fromAscList y