From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.help Subject: Re: will we ever have zero width assertions in regexps? Date: Wed, 26 Jan 2011 21:21:18 -0500 Organization: A noiseless patient Spider Message-ID: References: NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1296096052 21950 80.91.229.12 (27 Jan 2011 02:40:52 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Thu, 27 Jan 2011 02:40:52 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Thu Jan 27 03:40:49 2011 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1PiHmy-0001cC-Jp for geh-help-gnu-emacs@m.gmane.org; Thu, 27 Jan 2011 03:40:48 +0100 Original-Received: from localhost ([127.0.0.1]:41969 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PiHmy-0001Vz-5a for geh-help-gnu-emacs@m.gmane.org; Wed, 26 Jan 2011 21:40:48 -0500 Original-Path: usenet.stanford.edu!news.tele.dk!news.tele.dk!small.news.tele.dk!newsgate.cistron.nl!newsgate.news.xs4all.nl!news2.euro.net!xlned.com!feeder3.xlned.com!feeder.news-service.com!85.214.198.2.MISMATCH!eternal-september.org!feeder.eternal-september.org!.POSTED!not-for-mail Original-Newsgroups: gnu.emacs.help Original-Lines: 14 Injection-Info: mx03.eternal-september.org; posting-host="cDuFTaxWZtHn7h45EreUyw"; logging-data="3643"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX188OGB9qpKIu3Z0MRrYPLSL" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (gnu/linux) Cancel-Lock: sha1:85VOkQ8tXX51mdizJpAC7VVZn8A= sha1:17Hm76aMOb5qHFSX757ftOBmZo0= Original-Xref: usenet.stanford.edu gnu.emacs.help:184618 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:78776 Archived-At: > Indeed. I'm using Emacs 23.2.1, so I don't know whether this is already in > the latest CVS version. But assuming it's not, is this feature on the radar > of the developers? No. There hasn't been much demand/interest for it, tho IIRC someone posted a patch to implement it at some point in the past. I think there'd be more interest in extending regexps to PEG in a way similar to Lua's Lpeg. I myself would also be more interested in replacing the backtracking matcher with a non-backtracking one (for the cases where backtracking is not required by backrefs). Stefan