Well, I was thinking that way when I was starting learning Haskell. But then I realized that this "feature" would make code much harder to read. Suppose you have different thing all named "insertWith". You've got one somewhere in your program; how do YOU know when looking at the code after a month or so, which one is this? Certainly, given a smart IDE you can ask it; but I think that code should be clear just when you look at it, without any action. What CAN be useful is, IMHO, to make your IDE substitute this "M."s for you when you type. On 31 Aug 2008, at 22:21, Ryan Ingram wrote:
The point of having a strongly typed language is so the compiler can do more work for you. But right now I do a lot of typing (pun not intended) to appease the compiler.
Let me give you an example:
module Prob where import qualified Data.Map as M ...
newtype Prob p a = Prob { runProb :: [(a,p)] }
combine :: (Num p, Ord a) => Prob p a -> Prob p a combine m = Prob $ M.assocs $ foldl' (flip $ uncurry $ M.insertWith (+)) M.empty $ runProb m
Do you see it? All those "M." just seem dirty to me, especially because the compiler should be able to deduce them from the types of the arguments.
My proposal is to allow "ad-hoc" overloading of names; if a name is ambiguous in a scope, attempt to type-check the expression against each name. It is only an error if type-checking against all names fails. If type-checking succeeds for more than one then the expression is ambiguous and this is also an error.
Pros: shorter code, less busywork to please the compiler Cons: potentially exponential compile time?
Any thoughts?
-- ryan _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe