[Haskell-cafe] Restrictions on associated types for classes

[Tom Schrijvers]

> 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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