From mboxrd@z Thu Jan  1 00:00:00 1970
Path: news.gmane.org!.POSTED!not-for-mail
From: Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups: gmane.emacs.help
Subject: Re: re-search-forward hangs
Date: Mon, 30 Jul 2018 15:36:16 +0100
Organization: A noiseless patient Spider
Message-ID: <87bmao4wpr.fsf@bsb.me.uk>
References: <mailman.4412.1532953259.1292.help-gnu-emacs@gnu.org>
NNTP-Posting-Host: blaine.gmane.org
Mime-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Transfer-Encoding: 8bit
X-Trace: blaine.gmane.org 1532961500 25205 195.159.176.226 (30 Jul 2018 14:38:20 GMT)
X-Complaints-To: usenet@blaine.gmane.org
NNTP-Posting-Date: Mon, 30 Jul 2018 14:38:20 +0000 (UTC)
To: help-gnu-emacs@gnu.org
Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Mon Jul 30 16:38:16 2018
Return-path: <help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org>
Envelope-to: geh-help-gnu-emacs@m.gmane.org
Original-Received: from lists.gnu.org ([208.118.235.17])
	by blaine.gmane.org with esmtp (Exim 4.84_2)
	(envelope-from <help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org>)
	id 1fk9JP-0006Tw-TN
	for geh-help-gnu-emacs@m.gmane.org; Mon, 30 Jul 2018 16:38:16 +0200
Original-Received: from localhost ([::1]:52997 helo=lists.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org>)
	id 1fk9LW-0006hT-OE
	for geh-help-gnu-emacs@m.gmane.org; Mon, 30 Jul 2018 10:40:26 -0400
Original-Path: usenet.stanford.edu!goblin2!goblin1!goblin.stu.neva.ru!eternal-september.org!feeder.eternal-september.org!reader02.eternal-september.org!.POSTED!not-for-mail
Original-Newsgroups: gnu.emacs.help
Original-Lines: 24
Original-Injection-Info: reader02.eternal-september.org;
	posting-host="b3e133b6860e48286587f6bb1c7ef85a"; 
	logging-data="22583"; mail-complaints-to="abuse@eternal-september.org";
	posting-account="U2FsdGVkX1/TU81C1Gvm2pXW48u9t0+xyYb10gUb3j4="
Cancel-Lock: sha1:OHwTjeCwEri2zBOerqacpx9ATJI=
	sha1:SYJ85nLeyWIT0W/29BgL5y4NW+I=
X-BSB-Auth: 1.c0a2ad122ada9a368ad6.20180730153616BST.87bmao4wpr.fsf@bsb.me.uk
Original-Xref: usenet.stanford.edu gnu.emacs.help:223484
X-BeenThere: help-gnu-emacs@gnu.org
X-Mailman-Version: 2.1.21
Precedence: list
List-Id: Users list for the GNU Emacs text editor <help-gnu-emacs.gnu.org>
List-Unsubscribe: <https://lists.gnu.org/mailman/options/help-gnu-emacs>,
	<mailto:help-gnu-emacs-request@gnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/archive/html/help-gnu-emacs/>
List-Post: <mailto:help-gnu-emacs@gnu.org>
List-Help: <mailto:help-gnu-emacs-request@gnu.org?subject=help>
List-Subscribe: <https://lists.gnu.org/mailman/listinfo/help-gnu-emacs>,
	<mailto:help-gnu-emacs-request@gnu.org?subject=subscribe>
Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org
Original-Sender: "help-gnu-emacs"
	<help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org>
Xref: news.gmane.org gmane.emacs.help:117609
Archived-At: <http://permalink.gmane.org/gmane.emacs.help/117609>

Andreas Röhler <andreas.roehler@easy-emacs.de> writes:

> emacs -Q, when evaluating from in scratch-buffer
>
> (while (re-search-forward "" nil t 1))
>
> Emacs hangs.
>
> Same with plain
>
> (while (search-forward "" nil t 1))
>
> Expect it terminating.

Why do you expect a difference?  I would expect both to loop
indefinitely (and they do in my slightly older Emacs).

> Are there reasons for this?

Both loop because the match always succeeds.  Neither match moves point
so neither can fail.

-- 
Ben.