From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Kevin Rodgers Newsgroups: gmane.emacs.help Subject: Re: regexp to collapse multiple blank lines into one Date: Mon, 10 Oct 2005 12:33:50 -0600 Message-ID: References: <9rd2f.11472$vw6.9111@newsread1.news.atl.earthlink.net> <20051010172845.GX29712@SDF.LONESTAR.ORG> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Trace: sea.gmane.org 1128969411 19014 80.91.229.2 (10 Oct 2005 18:36:51 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Mon, 10 Oct 2005 18:36:51 +0000 (UTC) Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Mon Oct 10 20:36:50 2005 Return-path: Original-Received: from lists.gnu.org ([199.232.76.165]) by ciao.gmane.org with esmtp (Exim 4.43) id 1EP2VX-000251-3q for geh-help-gnu-emacs@m.gmane.org; Mon, 10 Oct 2005 20:36:19 +0200 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1EP2VW-0001o5-J6 for geh-help-gnu-emacs@m.gmane.org; Mon, 10 Oct 2005 14:36:18 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1EP2VK-0001np-Ct for help-gnu-emacs@gnu.org; Mon, 10 Oct 2005 14:36:06 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1EP2VI-0001nd-Al for help-gnu-emacs@gnu.org; Mon, 10 Oct 2005 14:36:06 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1EP2VI-0001na-87 for help-gnu-emacs@gnu.org; Mon, 10 Oct 2005 14:36:04 -0400 Original-Received: from [80.91.229.2] (helo=ciao.gmane.org) by monty-python.gnu.org with esmtp (TLS-1.0:RSA_AES_128_CBC_SHA:16) (Exim 4.34) id 1EP2VI-00084e-4U for help-gnu-emacs@gnu.org; Mon, 10 Oct 2005 14:36:04 -0400 Original-Received: from list by ciao.gmane.org with local (Exim 4.43) id 1EP2U4-0001QP-51 for help-gnu-emacs@gnu.org; Mon, 10 Oct 2005 20:34:48 +0200 Original-Received: from 207.167.42.60 ([207.167.42.60]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 10 Oct 2005 20:34:48 +0200 Original-Received: from ihs_4664 by 207.167.42.60 with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Mon, 10 Oct 2005 20:34:48 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-To: help-gnu-emacs@gnu.org Original-Lines: 28 Original-X-Complaints-To: usenet@sea.gmane.org X-Gmane-NNTP-Posting-Host: 207.167.42.60 User-Agent: Mozilla Thunderbird 0.9 (X11/20041105) X-Accept-Language: en-us, en In-Reply-To: <20051010172845.GX29712@SDF.LONESTAR.ORG> 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:30110 Archived-At: Neon Absentius wrote: > Actually that also works. The reason I used "\1" is that I had > already grouped the regexp so it saved me typing. ... > I don't understand what you don't understand :) My solutions replaces > one or more occurences of a regexp with a single occurence. Perhaps > you are worried abour efficiency? No, it was just that I read \(...\)+ as \(...+\). \(...\)+ is suspect to me, since in the general case ... can match different literal strings in the buffer and it wasn't obvious to me what \1 should refer to. I know see that the Emacs manual says If a particular `\( ... \)' construct matches more than once (which can easily happen if it is followed by `*'), only the last match is recorded. but I guess I was effected by my experience with a proprietary text processing language (which shall remain nameless) that prohibited such references. In any case, replacing \(^ C-q C-j \)+ with \1 is 10 key strokes, which is actually more typing than if you were to replace ^ C-q C-j + with C-q C-j (6 keys). -- Kevin Rodgers