Re: [Haskell-cafe] Restrictions on associated types for classes

17 Dec 2009

      ...
class MyClass k where
 type AssociatedType k :: *
Is there a way of requiring AssociatedType be of class Eq, say?
Have you tried:

{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE FlexibleContexts #-}

class Eq (AssociatedType k) => MyClass k where
   type AssociatedType k :: *

?

Cheers,

Tom

--
Tom Schrijvers

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