Class System current status

Taral taralx at
Thu May 11 13:30:46 EDT 2006

On 5/11/06, Stephanie Weirich <sweirich at> wrote:
> a) standardize on MPTC and FDs using rules from CHR paper.

>   - We're already in that state. There *is* a lot of Haskell code that
> uses FDs, it's just not Haskell 98 code. Whenever ATs take over, we'll
> still have to deal with this code.

In my opinion, this one holds the greatest weight. The current mass of
*useful* and *used* code that is written with and requires FDs is
possibly the most important consideration of all.

Given that FD *syntax* is well-defined, I see no reason not to
standardize it. It remains, however, to decide on what level of
*minimum* termination support Haskell' will insist upon. The CHR paper
(with the confluence improvements by Claus) is currently the most
promising option, and has an implementation (another important
consideration) in GHC.

Taral <taralx at>
"You can't prove anything."
    -- Gödel's Incompetence Theorem

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