From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Jean Louis Newsgroups: gmane.emacs.help Subject: Re: append, push, and add-to-list. Date: Mon, 5 Jul 2021 08:06:16 +0300 Message-ID: References: <8735suaw71.fsf@zoho.eu> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="8358"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Mutt/2.0.7+183 (3d24855) (2021-05-28) Cc: help-gnu-emacs , Emanuel Berg To: Hongyi Zhao Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Mon Jul 05 07:12:20 2021 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1m0Gu4-0001zc-8L for geh-help-gnu-emacs@m.gmane-mx.org; Mon, 05 Jul 2021 07:12:20 +0200 Original-Received: from localhost ([::1]:51780 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m0Gu3-0007ny-AT for geh-help-gnu-emacs@m.gmane-mx.org; Mon, 05 Jul 2021 01:12:19 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:44670) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m0GtY-0007nf-Tk for help-gnu-emacs@gnu.org; Mon, 05 Jul 2021 01:11:48 -0400 Original-Received: from stw1.rcdrun.com ([217.170.207.13]:52399) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m0GtX-0005Ki-9b for help-gnu-emacs@gnu.org; Mon, 05 Jul 2021 01:11:48 -0400 Original-Received: from localhost ([::ffff:197.157.34.164]) (AUTH: PLAIN admin, TLS: TLS1.3,256bits,ECDHE_RSA_AES_256_GCM_SHA384) by stw1.rcdrun.com with ESMTPSA id 0000000000057EBC.0000000060E29470.00004724; Sun, 04 Jul 2021 22:11:12 -0700 Mail-Followup-To: Hongyi Zhao , Emanuel Berg , help-gnu-emacs Content-Disposition: inline In-Reply-To: Received-SPF: pass client-ip=217.170.207.13; envelope-from=bugs@gnu.support; helo=stw1.rcdrun.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.23 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-mx.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.io gmane.emacs.help:131471 Archived-At: * Hongyi Zhao [2021-07-05 05:17]: > On Mon, Jul 5, 2021 at 12:19 AM Emanuel Berg via Users list for the > GNU Emacs text editor wrote: > > > > Hongyi Zhao wrote: > > > > > I've noticed there are some similar functions, i.e., append, > > > push, and add-to-list, for revising/updating the content of > > > a list. But I'm still not so clear on the specific use > > > scenarios for them. Consider the following command [1] > > > > `nconc', `cl-pushnew', (setq lst `(,@lst el)) ... > > Does the following append `el' to `lst'? > (defvar lst '()) ⇒ lst (setq lst `(,@lst el)) ⇒ (el) lst ⇒ (el) I see it does when variable `list' is defined in advance. -- Jean Take action in Free Software Foundation campaigns: https://www.fsf.org/campaigns In support of Richard M. Stallman https://stallmansupport.org/