Call Arity, oneShot, or both

Joachim Breitner mail at
Mon Oct 27 10:16:40 UTC 2014


Am Montag, den 27.10.2014, 03:39 -0400 schrieb David Feuer:
> Joachim Breitner כתב 
>         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.
> I was under the impression that the transformation was much more
> general than that, improving various recursive forms. Was I wrong?

It is more general, but that doesn’t mean that the general form occurs
in practice...

>  But aside from that, I would be astonished if the library authors
> were the only ones writing left-accumulating folds!

I’d expect most others to write their folds already in eta-expanded
form; it is rather unnatural to write it in non-expanded form.

Maybe if someone uses difference lists there is a possibility for Call
Arity to do something.


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

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