Type wildcards, was: Re: [Haskell] GHC Error question

John Meacham john at repetae.net
Thu Dec 7 20:06:54 EST 2006


On Thu, Dec 07, 2006 at 10:53:38AM -0500, J. Garrett Morris wrote:
> On 12/7/06, Lennart Augustsson <lennart at augustsson.net> wrote:
> >Speaking of wishlist, I'd also like to see context synonyms, e.g.,
> >context C a = (Ord a, Num a)
> 
> This is equivalent to John Meacham's class alias proposal, right?
> (http://repetae.net/john/recent/out/classalias.html)

is is a small part of it, the class alias proposal gives both a shorthand form
of refering to a set of class constraints, and a 'template language' of
sorts for declaring class instances. the instance declarations part is
the "meat" of the proposal, the shorthand form is more of a natural
consequence of it.

        John

-- 
John Meacham - ⑆repetae.net⑆john⑈


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