John Meacham wrote:
newtype Eq a => Set a = Set (List a) singleton :: Eq a => a -> Set a class Monad m where return :: a -> m ainstance Monad Set where return x = singleton xokay, our goal is to make this typesafe.
You shouldn't be able to, should you? Monad makes a promise that Set can't keep. In particular:
returnid :: (Monad m) => m (a -> a) returnid = return id bad :: Set (a -> a) bad = returnid _______________________________________________ Haskell-prime mailing list [email protected] http://haskell.org/mailman/listinfo/haskell-prime
