From: Alan Mackenzie <acm@muc.de>
To: YOUNG <breadncup@gmail.com>
Cc: help-gnu-emacs@gnu.org
Subject: Re: c preprocessor and indent problem in c-mode?
Date: Mon, 26 Jan 2009 09:00:47 +0000 [thread overview]
Message-ID: <20090126090047.GA1417@muc.de> (raw)
In-Reply-To: <035566ec-3070-441e-8040-6f44c5c0d96c@p36g2000prp.googlegroups.com>
Hi, there,
On Sun, Jan 25, 2009 at 04:46:38PM -0800, YOUNG wrote:
> Hi,
> If there is a following code, emacs does not present indent correctly.
> #incude <stdio.h>
> int main(void) {
> int a = 10;
> #ifdef AAA
> if (a == 10) { <====================== A
> printf("a:%d\n", a);
> #else
> if (b == 10) { <====================== B
> printf("b=10\n");
> #endif
> }
> #endif
> }
> If the curly brace is not closed before the preprocessor, emacs seems
> to confuse to make indent.
Yes.
> Is there anyone who know this problem and how to resolve?
Yes. CC Mode doesn't take account of the #ifdef and #else when parsing
braces. So it looks like the brace on line B is nested within the brace
on line A. This is a longstanding bug, which needs fundamental work in
CC Mode (and possibly the Emacs core) to fix. It may get fixed in the
medium future. Sorry!
A reasonable workaround, if the project you're working on will let you,
is to keep braces in #ifdefs (and #defines) balanced. You could thus
write this instead:
#ifdef AAA
if (a == 10) {
printf("a:%d\n", a);
}
#else
if (b == 10) {
printf("b=10\n");
}
#endif
--
Alan Mackenzie (Nuremberg, Germany).
prev parent reply other threads:[~2009-01-26 9:00 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-26 0:46 c preprocessor and indent problem in c-mode? YOUNG
2009-01-26 2:03 ` YOUNG
2009-01-26 9:00 ` Alan Mackenzie [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20090126090047.GA1417@muc.de \
--to=acm@muc.de \
--cc=breadncup@gmail.com \
--cc=help-gnu-emacs@gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this external index
https://git.savannah.gnu.org/cgit/emacs.git
https://git.savannah.gnu.org/cgit/emacs/org-mode.git
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.