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

Ah yes, this is very very very helpful. Thanks : ) Miguel's example is not quite as idiomatic, but...for some reason I find it beguiling nonetheless. On Thu, Dec 17, 2009 at 2:36 PM, Roman Leshchinskiy <rl@cse.unsw.edu.au> wrote:

On 18/12/2009, at 00:37, Stephen Lavelle wrote:

...

Given

class MyClass k where  type AssociatedType k :: *

Is there a way of requiring AssociatedType be of class Eq, say?

This works with -XFlexibleContexts:

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

Roman