[Haskell] GHC Error question

Rene de Visser Rene_de_Visser at hotmail.com
Fri Dec 8 12:57:49 EST 2006

There may be a heuristic that would help more programs to go through... but 
I prefer asking the programmer to make the desired behaviour explicit.


How can the user make this explicit?

With the

class C a b where
    op :: a -> a
instance C Int Int where
    op a = -a

test d = op d


I have been unable to figure out what type annotations I need to add to 
'test', for exampl,e to define test to be for the C Int Int instance.

Or is it simply impossible in GHC to give test a type signature and to use 
it as a useful function?


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