[Haskell-cafe] Re: ambiguous partially defined type problem

[Brian Hulley]

Maarten wrote:
> Only update (see code below) is a bit ugly (I have no idea why I need
> fixCastUpdate) 
>
>    update :: a -> (forall b. (ICustom b) => b -> b) -> a
>    update a f = f a

If you changed the type signature to:

    update :: a -> (a -> a) -> a

would the code compile without fixCastUpdate?

Regards, Brian.
-- 
Logic empowers us and Love gives us purpose.
Yet still phantoms restless for eras long past,
congealed in the present in unthought forms,
strive mightily unseen to destroy us.

http://www.metamilk.com