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: Visiting buffers programmatically Date: Fri, 11 Jun 2021 03:47:03 +0300 Message-ID: References: <5fc2e0a6-470e-0ebc-fe81-9eea2dd7fa5f@akwebsoft.com> 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="21596"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Mutt/2.0.7+183 (3d24855) (2021-05-28) Cc: MLEmacs To: Tim Johnson Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Fri Jun 11 02:48:53 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 1lrVLw-0005Sl-Ni for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 11 Jun 2021 02:48:52 +0200 Original-Received: from localhost ([::1]:55850 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lrVLv-0003n2-Pn for geh-help-gnu-emacs@m.gmane-mx.org; Thu, 10 Jun 2021 20:48:51 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:34262) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lrVLS-0003WO-PX for Help-gnu-emacs@gnu.org; Thu, 10 Jun 2021 20:48:22 -0400 Original-Received: from stw1.rcdrun.com ([217.170.207.13]:47127) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lrVLQ-00013T-0H for Help-gnu-emacs@gnu.org; Thu, 10 Jun 2021 20:48:22 -0400 Original-Received: from localhost ([::ffff:197.157.0.23]) (AUTH: PLAIN admin, TLS: TLS1.3,256bits,ECDHE_RSA_AES_256_GCM_SHA384) by stw1.rcdrun.com with ESMTPSA id 00000000000D59E1.0000000060C2B2B0.00002017; Thu, 10 Jun 2021 17:47:44 -0700 Mail-Followup-To: Tim Johnson , MLEmacs Content-Disposition: inline In-Reply-To: <5fc2e0a6-470e-0ebc-fe81-9eea2dd7fa5f@akwebsoft.com> Received-SPF: pass client-ip=217.170.207.13; envelope-from=bugs@gnu.support; helo=stw1.rcdrun.com X-Spam_score_int: -3 X-Spam_score: -0.4 X-Spam_bar: / X-Spam_report: (-0.4 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_SORBS_WEB=1.5, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no 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:130740 Archived-At: * Tim Johnson [2021-06-11 00:18]: > GNU Emacs 27.2 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.20, cairo > version 1.16.0) >  of 2021-06-04 ubuntu 20.04 > > I would like to write three simple elisp routines that would each visit one > of: > *scratch*, *messages* and *shell* > > For *messages* I would only be reading or copying text. > For *scratch* and *shell* I would be modifying those buffers. > > which elisp function is best for each of > these buffers? Here is function that will cycle over the list of buffer names: (defvar rcd-switch-to-buffer-list '("*scratch*" "*shell*" "*Messages*")) (defun rcd-switch-to-buffer () (interactive) (if (member (current-buffer) (mapcar (lambda (buffer) (get-buffer buffer)) rcd-switch-to-buffer-list)) (when (buffer-live-p (next-circular-list-item (mapcar (lambda (buffer) (get-buffer buffer)) rcd-switch-to-buffer-list) (current-buffer))) (switch-to-buffer (next-circular-list-item (mapcar (lambda (buffer) (get-buffer buffer)) rcd-switch-to-buffer-list) (current-buffer)))) (when (buffer-live-p (get-buffer (nth 0 rcd-switch-to-buffer-list))) (switch-to-buffer (nth 0 rcd-switch-to-buffer-list))))) and you need this one too: (defun next-circular-list-item (list previous-item) "Return the next element in the LIST by looking at PREVIOUS-ITEM. All elements in the LIST have to be different. If last element of LIST is equal to PREVIOUS-ITEM then first element is returned." (let ((last-element (car (last list)))) (cond ((eq last-element previous-item) (car list)) (t (nth 1 (member previous-item list)))))) Then M-x rcd-switch-to-buffer will cycle over the list of buffers. -- Jean Take action in Free Software Foundation campaigns: https://www.fsf.org/campaigns In support of Richard M. Stallman https://stallmansupport.org/