On 03/03/07, C Rodrigues <[EMAIL PROTECTED]> wrote:
class Foo a b | a -> b where foo :: a -> FooBox b data FooBox b = forall c. Foo b c => FooBox (Maybe c)
Existential boxes is indeed the method I've used to tackle this in practice. However, it's kind of annoying, hence my email asking whether there's a good reason it's not possible. I guess there are no theoretical limitations, because, as you've just shown, you can hack your way around it. -- -David House, [EMAIL PROTECTED] _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
