From: David Kastrup <dak@gnu.org>
To: emacs-devel@gnu.org
Subject: Re: `save-excursion' defeated by `set-buffer'
Date: Mon, 04 Jan 2010 18:34:50 +0100 [thread overview]
Message-ID: <87wrzxwz7p.fsf@lola.goethe.zz> (raw)
In-Reply-To: 47994.130.55.118.19.1262624933.squirrel@webmail.lanl.gov
"Davis Herring" <herring@lanl.gov> writes:
>> save-excursion only saves point in the current buffer, so
>>
>> (save-excursion (set-buffer foo) (goto-char (point-min)))
>>
>> will move point in foo and the point-saving done by save-excursion is
>> useless. So either you want to use
>
> If we know that (eq foo (current-buffer)), we should drop the
> `set-buffer'. If we know that not to be the case, we should use
> `with-current-buffer' (or perhaps `save-current-buffer'). But what if it
> could but needn't be?
And what if we don't have just (goto-char (point-min)), but some code
that might _revisit_ the original buffer (with set-buffer or otherwise)
and _move_ its point? Then save-excursion _will_ restore the original
point in the buffer at its end which otherwise would remain moved.
--
David Kastrup
next prev parent reply other threads:[~2010-01-04 17:34 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-12-20 19:19 `save-excursion' defeated by `set-buffer' Roland Winkler
2009-12-21 15:26 ` Stefan Monnier
2009-12-21 16:23 ` David Kastrup
2009-12-22 12:51 ` martin rudalics
2009-12-23 0:45 ` Stefan Monnier
2009-12-23 9:07 ` David Kastrup
2009-12-24 4:35 ` Stefan Monnier
2009-12-24 9:03 ` David Kastrup
2009-12-29 16:01 ` Stefan Monnier
2010-01-04 9:09 ` Drew Adams
2010-01-04 18:30 ` Stefan Monnier
2010-01-05 20:17 ` David Kastrup
2010-01-06 0:02 ` Drew Adams
2010-01-06 4:20 ` Stefan Monnier
2010-01-06 8:07 ` David Kastrup
2010-01-06 8:57 ` Drew Adams
2010-01-10 4:57 ` Stefan Monnier
2010-01-10 8:12 ` David Kastrup
2010-01-10 21:43 ` Stefan Monnier
2010-01-11 8:24 ` David Kastrup
2010-01-11 9:21 ` martin rudalics
2010-01-11 16:50 ` Stefan Monnier
2010-01-10 17:03 ` Drew Adams
2010-01-10 4:51 ` Stefan Monnier
2010-01-10 15:58 ` Harald Hanche-Olsen
2010-01-10 18:05 ` martin rudalics
2010-01-10 18:06 ` Drew Adams
2010-01-10 19:44 ` Harald Hanche-Olsen
2009-12-24 14:04 ` Roland Winkler
2010-01-04 17:08 ` Davis Herring
2010-01-04 17:34 ` David Kastrup [this message]
2010-01-04 18:33 ` Stefan Monnier
-- strict thread matches above, loose matches on Subject: below --
2009-12-18 9:20 Eli Zaretskii
2009-12-18 15:29 ` Juanma Barranquero
2009-12-18 15:58 ` Thierry Volpiatto
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