On 13/10/2004, at 10:02 AM, MR K P SCHUPKE wrote:

Okay, I see the Generic type class stuff does not support multi
parameter type classes. I guess I am stuck - any suggestions as to
how best do this?

I wish to be able to derive type level labels for datatypes, like
the following:

data Fred a = Fred a deriving TTypeable

generates the instance:

instance TTypeable a al => TTypeable (Fred a) (NCons (N3 (N4 (N5 Nil))) (TCons al Nil))

If you are happy to live on the edge a bit (which you seem to be happy with, considering that you're playing with GHC CVS ;), Template Haskell might be one way to do it. See "Template Haskell: A Report from the Field", a paper where Ian Lynagh does exactly what you're trying to do:


    http://www.haskell.org/th/papers.html


-- % Andre Pang : trust.in.love.to.save

_______________________________________________
Glasgow-haskell-users mailing list
[EMAIL PROTECTED]
http://www.haskell.org/mailman/listinfo/glasgow-haskell-users

Reply via email to