From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Barry Margolin Newsgroups: gmane.emacs.help Subject: Re: empty-line-p Date: Fri, 30 Mar 2007 01:46:53 -0400 Organization: Symantec Message-ID: References: NNTP-Posting-Host: lo.gmane.org X-Trace: sea.gmane.org 1175236679 11593 80.91.229.12 (30 Mar 2007 06:37:59 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Fri, 30 Mar 2007 06:37:59 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Fri Mar 30 08:37:58 2007 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 4.50) id 1HXAkE-0000Z0-VL for geh-help-gnu-emacs@m.gmane.org; Fri, 30 Mar 2007 08:37:55 +0200 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HXAmt-0008BT-CD for geh-help-gnu-emacs@m.gmane.org; Fri, 30 Mar 2007 01:40:39 -0500 Original-Path: shelby.stanford.edu!newshub.stanford.edu!postnews.google.com!news3.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local01.nntp.dca.giganews.com!nntp.comcast.com!news.comcast.com.POSTED!not-for-mail Original-NNTP-Posting-Date: Fri, 30 Mar 2007 00:46:53 -0500 Original-Newsgroups: gnu.emacs.help Mail-Copies-To: nobody User-Agent: MT-NewsWatcher/3.5.2 (PPC Mac OS X) X-Copies-To: never Original-Lines: 27 Original-NNTP-Posting-Host: 24.34.108.171 Original-X-Trace: sv3-bqJD8IzTcnHO4hL/MdTTjSClf3HaxDNh366+8zMEwGAm0rL9KhiCyQMcO//ixClZ5rwZXrCKNM+Cckk!U0FScZgxD9bxOuniRyYbgwnSSls8oEv/0Scz0bQcTgVlvUrdygfGXBXoXpnIzBAlPCrQ3KW2EAAE!9xIZPibmsBVYEekPA091hU3k6DqhqXybl97S20e3HA== Original-X-Complaints-To: abuse@comcast.net X-DMCA-Complaints-To: dmca@comcast.net X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.34 Original-Xref: shelby.stanford.edu gnu.emacs.help:146695 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:42300 Archived-At: In article , Stefan Monnier wrote: > > (if (looking-at "^[ \t\f\r]*$") > > t > > nil))) > > (if t nil) > > is an eta-regexp, which can be advantageously reduced to just . > > > Stefan > > > PS: The classical eta-regexp is (lambda (x) ( x)), which is equivalent to > just . Another variant is (cons (car ) (cdr )), which > eta-reduces to just . That last one is different, because the new cons is not eq to the original . -- Barry Margolin, barmar@alum.mit.edu Arlington, MA *** PLEASE post questions in newsgroups, not directly to me *** *** PLEASE don't copy me on replies, I'll read them in the group ***