From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Thorsten Jolitz Newsgroups: gmane.emacs.help Subject: Re: Why doesn't nconc change my variable? Date: Sun, 05 Oct 2014 12:52:03 +0200 Message-ID: <87zjda23ho.fsf@gmail.com> References: <87y4svl2ku.fsf@wmi.amu.edu.pl> <3867d7c2-936d-4441-91d6-3b12dc959391@default> <87vbnylu3z.fsf@wmi.amu.edu.pl> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1412506369 6384 80.91.229.3 (5 Oct 2014 10:52:49 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 5 Oct 2014 10:52:49 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Sun Oct 05 12:52:42 2014 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1XajQf-0007yG-Bf for geh-help-gnu-emacs@m.gmane.org; Sun, 05 Oct 2014 12:52:41 +0200 Original-Received: from localhost ([::1]:46988 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XajQf-0000Ee-0G for geh-help-gnu-emacs@m.gmane.org; Sun, 05 Oct 2014 06:52:41 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:36674) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XajQP-0000EQ-0D for help-gnu-emacs@gnu.org; Sun, 05 Oct 2014 06:52:31 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XajQI-0002PH-VY for help-gnu-emacs@gnu.org; Sun, 05 Oct 2014 06:52:24 -0400 Original-Received: from plane.gmane.org ([80.91.229.3]:46731) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XajQI-0002Og-Pl for help-gnu-emacs@gnu.org; Sun, 05 Oct 2014 06:52:18 -0400 Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1XajQF-0007ml-L2 for help-gnu-emacs@gnu.org; Sun, 05 Oct 2014 12:52:15 +0200 Original-Received: from e178190193.adsl.alicedsl.de ([85.178.190.193]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 05 Oct 2014 12:52:15 +0200 Original-Received: from tjolitz by e178190193.adsl.alicedsl.de with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 05 Oct 2014 12:52:15 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 17 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: e178190193.adsl.alicedsl.de User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) Cancel-Lock: sha1:4UuApi8P2TtlpB/HUCfAFkQpft4= X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 80.91.229.3 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:100283 Archived-At: Marcin Borkowski writes: >>> (setq my-list (nconc my-list '("wtf"))) > That I didn't read earlier; I've read it now, and still don't get it. even w/o understanding the details, one can simply try to internalize the rule that after destructive list operations a setq is necessary to make changes take effect, i.e. always use this (pseudo-code) pattern: ,---- | (setq X (destuctively-modify X)) `---- -- cheers, Thorsten