On 19/03/07, Fawzi Mohamed
This is is very ugly in my opinion, because for me a type class should represent something more than just a way to overload, is something is not a number then it should not have the class Num.
Num is a collection of types whose members can be added and subtracted and so on. As numbers are the most common example of this, one could say the members of Num _act like numbers_, rather than are numbers in themselves. Really typeclasses are all about overloading. For example, Eq is the collection of types that the equality predicate (==) applies to. I don't see this as ugly; quite the contrary, in that if you know a type instantiates Eq you can use (==) without worrying about using a type-specific equality predicate. E.g. it's nice to see the same (==) everywhere rather than seeing (say) (Int.==), (Bool.==) and so on. -- -David House, dmhouse@gmail.com