RE: Type classes in GADTs

Thanks for the explanation. I see how this wouldn't behave nicely with automatic class constraint inference. I didn't test the example on any other GHC versions. I will probably end up passing in the Eq dictionary from outside like Daniil suggested. I would prefer to do the following, but GHC doesn't accept the type signature. evidenceOfEq :: CAOp a -> (Eq a => b) -> b Neither does it accept data EqConstraint a b = EqConstraint (Eq a => b). Foiled again. _________________________________________________________________ Want to read Hotmail messages in Outlook? The Wordsmiths show you how. http://windowslive.com/connect/post/wedowindowslive.spaces.live.com-Blog-cns...