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                    2010
                
            
            
                15 Jul
                
                '10
                
            
            
            
        
    
                3:09 a.m.
            
        On Thu, Jul 15, 2010 at 3:13 AM, Michael Snoyman 
You could also use type families for this, but I believe you cannot express the "Show" superclass: class MyClass a where type MyResult a fn :: a -> MyResult a
I guess this works: class Show (MyResult a) => MyClass a where type MyResult a fn :: a -> MyResult a HTH, -- Felipe.