This seems similar to my 'supertyping' proposal. The basic gist was that you can declare a superclass (which must have a subset of the members of the original class) after the declaration of the original class...
my original message is here: http://repetae.net/john/computer/haskell/supertyping.txt John On Sun, Jan 12, 2003 at 09:37:25AM -0500, Dylan Thurston wrote: > On Wed, Jan 08, 2003 at 02:24:06PM +0100, Marc Ziegert wrote: > > --------------------It would be nice to be able to overload class-functions like >classes: > > > > instance (+), (-) -> Vector where > > (+) v1 v2 = ... > > (-) v1 v2 = ... > > ... > > You seem to be making a general complaint, but there's been extensive > discussion about this particular instance. I agree with you that the > numeric hierarchy is too coarsely grained right here; do a search on > the archives for "numeric prelude" for an extensive discussion. > > Your proposals seem interesting, but seem hard to implement/make > precise at first glance. > > Best, > Dylan Thurston -- --------------------------------------------------------------------------- John Meacham - California Institute of Technology, Alum. - [EMAIL PROTECTED] --------------------------------------------------------------------------- _______________________________________________ Haskell mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell
