From: Andreas Schwab <schwab@suse.de>
Cc: Zack Weinberg <zack@codesourcery.com>,
Stefan Monnier <monnier@iro.umontreal.ca>,
emacs-devel@gnu.org
Subject: Re: byte-opt.el addition - optimize list of compile-time constants
Date: Thu, 09 Dec 2004 11:34:13 +0100 [thread overview]
Message-ID: <je653boj4q.fsf@sykes.suse.de> (raw)
In-Reply-To: <200412082133.12630.pogonyshev@gmx.net> (Paul Pogonyshev's message of "Wed, 8 Dec 2004 21:33:12 +0200")
Paul Pogonyshev <pogonyshev@gmx.net> writes:
> Zack Weinberg wrote:
>> I seriously wonder how much would break if this optimization were
>> implemented for 'list'. My suspicion is that people don't commonly
>> apply 'eq' to lists in the first place.
>
> You are very wrong here. While it will hardly break sane code,
> `eq' is _very_ often applied to cons cells, e.g. lists.
Also 'list' is sometimes intentionally used to create a new cons that can
be changed by side effect. If it were optimized to a constant the side
effect would now change a literal.
Andreas.
--
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5
"And now for something completely different."
prev parent reply other threads:[~2004-12-09 10:34 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-12-08 9:21 byte-opt.el addition - optimize list of compile-time constants Zack Weinberg
2004-12-08 16:56 ` Stefan Monnier
2004-12-08 18:59 ` Zack Weinberg
2004-12-08 19:27 ` Stefan Monnier
2004-12-08 19:45 ` Zack Weinberg
2004-12-08 19:56 ` Stefan Monnier
2004-12-08 20:14 ` Nick Roberts
2004-12-08 22:47 ` Zack Weinberg
2004-12-08 23:40 ` Stefan Monnier
2004-12-09 1:20 ` Zack Weinberg
2004-12-09 2:11 ` Stefan Monnier
2004-12-09 2:33 ` Zack Weinberg
2004-12-09 2:46 ` Miles Bader
2004-12-09 3:08 ` Zack Weinberg
2004-12-09 3:28 ` Miles Bader
2004-12-09 3:48 ` Zack Weinberg
2004-12-09 4:04 ` Miles Bader
2004-12-09 4:41 ` Zack Weinberg
2004-12-09 4:52 ` Stefan Monnier
2004-12-09 5:33 ` Zack Weinberg
2004-12-09 5:39 ` Miles Bader
2004-12-09 6:49 ` Zack Weinberg
2004-12-09 15:22 ` Thien-Thi Nguyen
2004-12-10 5:50 ` Richard Stallman
2004-12-09 9:22 ` David Kastrup
2004-12-09 4:54 ` Miles Bader
2004-12-09 9:20 ` David Kastrup
2004-12-09 4:35 ` Stefan Monnier
2004-12-09 4:55 ` Zack Weinberg
2004-12-09 5:13 ` Stefan Monnier
2004-12-09 9:10 ` David Kastrup
2004-12-08 19:33 ` Paul Pogonyshev
2004-12-09 10:34 ` Andreas Schwab [this message]
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