I'm assuming you're not fond of the way the print function handles Strings?
With GHC you can do this:
{-# OPTIONS -fallow-overlapping-instances #-} {-# OPTIONS -fallow-undecidable-instances #-}
class Show a => MyShow a where show_ :: a -> String instance MyShow String where show_ s = s instance (Show a) => MyShow a where show_ s = show s
I'm curious why this works. How does GHC know to pick the MyShow String instance instead of the one coming from Show String? I expect there's no way to do this without undecidable instances, is there? I try to stay away from that flag nowadays, since I've seen some strange unpredictable behavior from it in the past (the unpredictability of the behavior may come from the fact that I don't know how the inference algorithm works). Luke