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: How to save custom variable programmatically? Date: Tue, 17 Nov 2020 18:44:07 +0300 Message-ID: References: <87blg5e9re.fsf@web.de> <87o8k5b7oq.fsf@web.de> <87h7pwgbg1.fsf@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="37824"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Mutt/2.0 (3d08634) (2020-11-07) Cc: help-gnu-emacs@gnu.org To: Michael Heerdegen Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Tue Nov 17 17:18:06 2020 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 1kf3gD-0009iy-KJ for geh-help-gnu-emacs@m.gmane-mx.org; Tue, 17 Nov 2020 17:18:05 +0100 Original-Received: from localhost ([::1]:50220 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kf3gC-0004kY-MI for geh-help-gnu-emacs@m.gmane-mx.org; Tue, 17 Nov 2020 11:18:04 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:34710) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kf3fN-0004MC-UK for help-gnu-emacs@gnu.org; Tue, 17 Nov 2020 11:17:14 -0500 Original-Received: from static.rcdrun.com ([95.85.24.50]:41705) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kf3fK-0002k3-Lr for help-gnu-emacs@gnu.org; Tue, 17 Nov 2020 11:17:13 -0500 Original-Received: from localhost ([::ffff:41.202.241.56]) (AUTH: PLAIN admin, TLS: TLS1.2,256bits,ECDHE_RSA_AES_256_GCM_SHA384) by static.rcdrun.com with ESMTPSA id 00000000002C0006.000000005FB3F764.00002EFD; Tue, 17 Nov 2020 16:16:35 +0000 Content-Disposition: inline In-Reply-To: <87h7pwgbg1.fsf@web.de> Received-SPF: pass client-ip=95.85.24.50; envelope-from=bugs@gnu.support; helo=static.rcdrun.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/11/17 10:11:24 X-ACL-Warn: Detected OS = Linux 3.11 and newer [fuzzy] 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:125296 Archived-At: * Michael Heerdegen [2020-11-11 00:17]: > Jean Louis writes: > > > Thank you. If you have ready simplest example it may be useful for > > review. > > Simplest? Ok, that might be possible. Let's make a wrapper holding a > single value that is savable: > > #+begin_src emacs-lisp > (defclass my-persistent (eieio-persistent) > ((data :initarg :data))) > > (defun my-save-in-location (thing file) > (let ((obj (my-persistent :data thing))) > (setf (oref obj file) file) > (eieio-persistent-save obj))) > This is not only a nice abstraction. eieio-persistent has some > (programmable) knowledge about how to print and "restore" objects where > a normal print+read cycle would not work. > > Michael. I remember from Common Lisp about `defstruc' and more than that I did not use. But I remember `defstruct' preparing various methods (probably methods) automatically. From there I understand this and keep it as note until I come to implement it. As it is built-in, it offers straight solution, good to know! Jean