Am Mittwoch 03 Juni 2009 06:12:46 schrieb Michael Snoyman: > I made two changes: > > 1. You had the arguments to M.lookup backwards. > 2. lookup does not return any generalized Monad, just Maybe (I think that > should be changed).
Data.Map.lookup used to return a value in any monad you wanted, I believe until 6.8 inclusive. I don't think it's going to change again soon. > I added the simple liftMaybe function to convert the > Maybe result into something that will work with your state monad. > > Michael _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
