From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Andreas Politz Newsgroups: gmane.emacs.help Subject: Re: How could I modify list element? Date: Tue, 09 Dec 2008 17:36:21 +0100 Organization: FH-Trier Message-ID: <1228840648.405357@arno.fh-trier.de> References: NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1228840857 7871 80.91.229.12 (9 Dec 2008 16:40:57 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 9 Dec 2008 16:40:57 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Tue Dec 09 17:42:01 2008 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 1LA5eh-0005GG-Au for geh-help-gnu-emacs@m.gmane.org; Tue, 09 Dec 2008 17:41:51 +0100 Original-Received: from localhost ([127.0.0.1]:33389 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LA5dW-0005hy-3b for geh-help-gnu-emacs@m.gmane.org; Tue, 09 Dec 2008 11:40:38 -0500 Original-Path: news.stanford.edu!headwall.stanford.edu!newsfeed.stanford.edu!news.tele.dk!news.tele.dk!small.news.tele.dk!kanaga.switch.ch!switch.ch!news.belwue.de!news.uni-kl.de!not-for-mail Original-Newsgroups: gnu.emacs.help Original-Lines: 23 Original-NNTP-Posting-Host: 143-93-54-11.arno.fh-trier.de Original-X-Trace: news.uni-kl.de 1228840694 14519 143.93.54.11 (9 Dec 2008 16:38:14 GMT) Original-X-Complaints-To: usenet@news.uni-kl.de Original-NNTP-Posting-Date: Tue, 9 Dec 2008 16:38:14 +0000 (UTC) User-Agent: Mozilla-Thunderbird 2.0.0.17 (X11/20081018) In-Reply-To: Cache-Post-Path: arno.fh-trier.de!unknown@dslb-088-069-050-088.pools.arcor-ip.net X-Cache: nntpcache 3.0.1 (see http://www.nntpcache.org/) Original-Xref: news.stanford.edu gnu.emacs.help:165173 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:60502 Archived-At: richardeng wrote: > Hi all, > setcar/setcdr is not convenient. > In a long list, ex. > (setq a '(a b c d e f g)) > I want to change 'e to 'E. > I need a function: (set-list-elt list old-elt new-elt) > > How? translate list to vector, modify, then turn it back??? > > Why don't you ... (let ((list '(a b c d e))) (or (and (require 'cl nil t) (substitute 'E 'e list)) (mapcar #'(lambda (elt) (if (eq elt 'e) 'E elt)) list))) -ap