classes and instances

[Russo, Tom]

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Hello,

I'm learning haskell and I'm having some trouble with type classes.  I
understand them conceptually, but when I try to create an instance I run
into problems.  As a simple example, I create a class called ToInt:

>	class ToCh a where
>		int :: a -> Int

Then I create an instance:

>	instance ToInt Int where:
>		int n = n

However, when I try to use the function int :: Int -> Int at the hugs
prompt, I get the following error message:

Main> int 5
ERROR - Unresolved overloading
*** Type       : (Num a, ToInt a) => Int
*** Expression : int 5

Can someone explain what the problem is, and how to interpret the error
message I'm getting?

thanks
_t



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