Re: [Haskell-cafe] Re: Positive integers

On 3/29/06, Aaron Denney wrote:

(And yes, we desperately need something like class aliases.)

You mean like this? class Foo a b where foo :: a -> b class Foo a b => Bar a b where instance Foo a b => Bar a b where This will make every instance of Foo one of Bar, and make sure every instance of Bar is an instance of Foo.