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From: ludo@gnu.org (Ludovic Courtès)
To: guile-devel@gnu.org
Subject: Re: Will guile support R7RS terminating "equal?" in the presence of cycle?
Date: Sat, 01 Sep 2012 15:30:26 +0200	[thread overview]
Message-ID: <87wr0dq39p.fsf@gnu.org> (raw)
In-Reply-To: E1T7e4E-0007ur-Pe@fenris.runbox.com

Hi,

"David A. Wheeler" <dwheeler@dwheeler.com> skribis:

> *However*, the current R7RS draft for "equal?" requires termination
> even in the presence of cycles, as well as impose other requirements
> on "write" and "display" in the presence of cycles.  Will guile
> support such changes?  I worry that these new requirements on "equal?"
> will have such a high overhead that people won't do it.  But perhaps
> those fear are misplaced.

Are you talking about termination in the case of circular lists, or for
arbitrary data structures?

The former is easy and reasonably cheap, but the latter may require more
work, indeed.

Thanks,
Ludo’.




  reply	other threads:[~2012-09-01 13:30 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-01  3:08 Will guile support R7RS terminating "equal?" in the presence of cycle? David A. Wheeler
2012-09-01 13:30 ` Ludovic Courtès [this message]
2012-09-02 14:50 ` Ian Price
2012-09-02 15:17   ` David A. Wheeler
2012-09-02 18:43     ` Stefan Israelsson Tampe
2012-09-02 22:07       ` Ludovic Courtès
2012-09-03 13:55         ` Stefan Israelsson Tampe
2012-09-08 16:56           ` Mark H Weaver
2012-09-08 17:00             ` Stefan Israelsson Tampe
2012-09-09  1:35               ` Alex Shinn
2012-09-09  3:41                 ` Mark H Weaver
2012-09-10  9:21                   ` William ML Leslie
2012-09-09 17:14                 ` Stefan Israelsson Tampe
2012-09-03 17:56         ` Stefan Israelsson Tampe
2012-09-03 21:12           ` Ludovic Courtès
2012-09-04  5:35             ` Stefan Israelsson Tampe

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