Hi > > full -> Maybe (item, full) > > Hrm, what exactly is the return data here? Is is the head and the > tail if the list has >= 1 item, or Nothing otherwise? Or...?
Yes, its the projection onto another type: [] = Nothing (x:xs) = Just (x, xs) > What is the problem with MPTC in base? MPTC is not a part of any Haskell standard. The rules surrounding MPTC are not clear. People want to remove MPTC's/functional dependencies, or modify them with associated types. Compilers such as nhc and yhc can't implement them. Once they are in Haskell', with an associated set of restrictions/overlap rules etc, then they can be freely used with the base library. Thanks Neil _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
