From: Miles Bader <miles.bader@necel.com>
To: emacs-devel@gnu.org
Subject: Re: Using empty_string as the only "" string
Date: Wed, 25 Apr 2007 10:47:59 +0900 [thread overview]
Message-ID: <buoejm98bsg.fsf@dhapc248.dev.necel.com> (raw)
In-Reply-To: yoij1wi9jq2d.fsf@gamma02.me.chalmers.se
bojohan+news@dd.chalmers.se (Johan Bockgård) writes:
>> I disagree. I don't think most people expect much one way or the other
>> in this case, _especially_ because we're talking about lexical constants
>> (for instance, I expect very few people would be surprised if the
>> compiler merged various lexical constants).
>
> How about this then?
>
> (let ((s1 (concat "ab" "c"))
> (s2 (concat "a" "bc")))
> (eq s1 s2)))))
..
> ** Prevent byte compiler from causing spurious string sharing
> when it optimizes away calls to functions such as concat.
S1 and S2 are not lexical constants -- and more importantly, the
`concat' function makes a specific guarantee that it will always return
a new string.
-Miles
--
`There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.'
next prev parent reply other threads:[~2007-04-25 1:47 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-04-24 16:32 Using empty_string as the only "" string Dmitry Antipov
2007-04-24 17:05 ` Juanma Barranquero
2007-04-24 18:11 ` Andreas Schwab
2007-04-24 18:50 ` Juanma Barranquero
2007-04-24 21:38 ` Andreas Schwab
2007-04-24 21:54 ` Juanma Barranquero
2007-04-24 22:11 ` Andreas Schwab
2007-04-24 22:54 ` Juanma Barranquero
2007-04-24 21:57 ` David Kastrup
2007-04-24 22:07 ` Lennart Borgman (gmail)
2007-04-24 22:29 ` David Kastrup
2007-04-24 22:35 ` Andreas Schwab
2007-04-25 0:55 ` Kenichi Handa
2007-04-25 9:51 ` Andreas Schwab
2007-04-25 9:58 ` David Kastrup
2007-04-25 10:50 ` Andreas Schwab
2007-04-24 22:40 ` Lennart Borgman (gmail)
2007-04-24 22:12 ` Andreas Schwab
2007-04-24 22:31 ` David Kastrup
2007-04-24 22:56 ` Andreas Schwab
2007-04-24 21:39 ` Miles Bader
2007-04-24 21:45 ` Juanma Barranquero
2007-04-24 22:11 ` Miles Bader
2007-04-24 22:59 ` Juanma Barranquero
2007-04-24 23:37 ` Miles Bader
2007-04-24 23:44 ` Johan Bockgård
2007-04-25 1:47 ` Miles Bader [this message]
2007-04-25 14:52 ` Richard Stallman
2007-04-26 15:03 ` Daniel Brockman
2007-04-27 20:40 ` Richard Stallman
2007-04-25 2:05 ` Richard Stallman
2007-04-25 12:00 ` Juanma Barranquero
2007-04-25 2:05 ` Richard Stallman
2007-04-24 17:48 ` Stefan Monnier
2007-04-25 2:05 ` Richard Stallman
2007-04-26 14:24 ` Dmitry Antipov
2007-04-25 2:05 ` Richard Stallman
-- strict thread matches above, loose matches on Subject: below --
2007-04-25 5:38 using " dmantipov
2007-04-25 5:49 ` Miles Bader
2007-04-25 11:50 ` Juanma Barranquero
2007-04-25 11:56 ` Kenichi Handa
2007-04-25 13:22 ` Dmitry Antipov
2007-04-25 16:07 ` Stefan Monnier
2007-04-26 4:23 ` Richard Stallman
2007-04-26 13:03 ` Dmitry Antipov
2007-04-27 6:00 ` Richard Stallman
2007-04-27 10:04 ` Dmitry Antipov
2007-04-27 10:29 ` David Kastrup
2007-04-28 4:06 ` Richard Stallman
2007-04-28 8:54 ` Dmitry Antipov
2007-04-28 18:35 ` Richard Stallman
2007-06-05 15:43 ` Juanma Barranquero
2007-06-05 19:17 ` Richard Stallman
2007-06-05 19:45 ` Juanma Barranquero
2007-06-06 1:17 ` Stefan Monnier
2007-06-06 11:04 ` Juanma Barranquero
2007-06-06 22:09 ` Richard Stallman
2007-06-08 15:49 ` Juanma Barranquero
2007-06-08 19:16 ` Stefan Monnier
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