[Haskell-cafe] Overloading in a sub-class

Hi, Below are two questions concerning overloading in a sub-class. Thanks, Pat class Numb0 a where (+) :: a -> a -> a negate :: a -> a instance Numb0 Int where x + y = y negate x = x -- Are + and negate part of the signature of Numb1? class Numb0 a => Numb1 a where -- Is it possible to override these operations in instances of Numb1? -- Something like: -- instance Numb1 Float where -- x + y = y -- negate x = x -- Or even using Int as in the super class instance: -- instance Numb1 Int where -- x + y = y -- negate x = x This message has been scanned for content and viruses by the DIT Information Services E-Mail Scanning Service, and is believed to be clean. http://www.dit.ie