Call Arity, oneShot, or both

Joachim Breitner mail at
Sun Oct 26 16:06:44 UTC 2014


Am Sonntag, den 26.10.2014, 10:56 -0400 schrieb David Feuer:
> > There is also the option of combining both. Then we do not get the
> > regression, but still the improvement for fft2:
> I *definitely* think we should leave Call Arity in place by default
> unless and until something strictly better comes along. One very nice
> feature is that it works for a lot of user-written code of various
> kinds without the user having to do *anything* special.

That would be great! But do we have evidence of this user-written code
that benefits? So far I have only seen relevant improvement due to
list-fusion a left-foldish function.

> oneShot seems more limited in applicability, for use primarily in
> library code. So I would personally think that it should be added,
> with an option, of course, to turn it off. I would also go for
> documenting it as experimental and provisional.

well, either we put in oneShot and use it for foldl etc. (so it wouldn’t
be optional) or we leave it out completely.


Joachim “nomeata” Breitner
  mail at joachim-breitner.de
  Jabber: nomeata at  • GPG-Key: 0xF0FBF51F
  Debian Developer: nomeata at

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