>
> I agree; Haskell 2 should have existential (and universal) types. I
> also think it should have both extensible records and extensible
> variants. (See the following paper for more information on these.
> TREX is an implementation of half of this system; it has the
> extensible records but not extensible variants.)
>
> Carl Witty
> [EMAIL PROTECTED]
>
Just a question, Is there anyone trying to implement extensible variants?
I can simulate them with the "Subtyping" trick of S. Liang, P. Hudak, M.
Jones [1], but I am not very happy with that solution.
Regards, Jose E. Labra
[1] S. Liang, P. Hudak, M. Jones, Monad transformers and modular
interpreters, POPL'94: 21st ACM SIGPLAN-SIGACT Symposium on Principles of
Programming Languages, San Francisco, California (1995).
