forall and class contexts

[Hal Daume III]

> >  class (Eq (forall a. t a), Monad t) => C t
> 
> more logically,
> 
>   class (forall a. Eq (t a), Monad t) => C t

and more usefully,

  class (forall a . Eq a => Eq (t a), Monad t) => C t

 - Hal