"cartesian classes"

[Frank Atanassow]

David Bergman wrote (on 26-11-02 01:29 -0500):
> I would like to know if anyone (maybe Mark P) knows the status of
> "Cartesian classes" in different Haskell implementations. I.e., does
> anyone implement the suggested functional dependencies or the less
> general parameterized type classes?
> 
> I have need for the multi-variable classes quite often (especially in a
> genetic algorithm framework I am building in Haskell). Although I would
> hesitate to extend beyond Haskell 98, if there exist a common view on
> how to best implement Cartesian classes (read "it will be part of
> Haskell 2") and/or a stable implementation for it, I am willing to be a
> bit adventurous...

What do you mean by "cartesian classes"? Do you mean multi-parameter type
classes?

They're supported by GHC and Hugs, but not NHC98 or HBC. The same goes for
functional dependencies.

-- 
Frank