[Haskell-cafe] Overloading in a sub-class

[Patrick Browne]

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