From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Marcin Borkowski Newsgroups: gmane.emacs.help Subject: Re: Persistence of variables Date: Wed, 28 Mar 2018 21:12:53 +0200 Message-ID: <87tvt0qaiy.fsf@mbork.pl> References: <87a7v20xlf.fsf@mbork.pl> <83a7v1lxxz.fsf@gnu.org> <87605p28ma.fsf@mbork.pl> <874ll94uvs.fsf@ericabrahamsen.net> <77e3430c-8533-4962-92fa-3b87e2226563@default> <874ll3bo90.fsf@ericabrahamsen.net> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1522264381 22471 195.159.176.226 (28 Mar 2018 19:13:01 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 28 Mar 2018 19:13:01 +0000 (UTC) User-Agent: mu4e 1.1.0; emacs 27.0.50 Cc: help-gnu-emacs@gnu.org To: Eric Abrahamsen Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Wed Mar 28 21:12:57 2018 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1f1GVF-0005iU-50 for geh-help-gnu-emacs@m.gmane.org; Wed, 28 Mar 2018 21:12:57 +0200 Original-Received: from localhost ([::1]:40677 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f1GXI-0007qS-Ei for geh-help-gnu-emacs@m.gmane.org; Wed, 28 Mar 2018 15:15:04 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:49677) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f1GVm-0006ek-Pw for help-gnu-emacs@gnu.org; Wed, 28 Mar 2018 15:13:32 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f1GVi-0004g1-Q7 for help-gnu-emacs@gnu.org; Wed, 28 Mar 2018 15:13:30 -0400 Original-Received: from mail.mojserwer.eu ([195.110.48.8]:54770) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f1GVi-0004fo-Hh for help-gnu-emacs@gnu.org; Wed, 28 Mar 2018 15:13:26 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by mail.mojserwer.eu (Postfix) with ESMTP id B0EF6E6778; Wed, 28 Mar 2018 21:13:25 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at mail.mojserwer.eu Original-Received: from mail.mojserwer.eu ([127.0.0.1]) by localhost (mail.mojserwer.eu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id w4sZgXawXY_X; Wed, 28 Mar 2018 21:13:21 +0200 (CEST) Original-Received: from localhost (static-dwadziewiec-jedenpiec7.echostar.pl [109.232.29.157]) by mail.mojserwer.eu (Postfix) with ESMTPSA id 4138CE6700; Wed, 28 Mar 2018 21:13:21 +0200 (CEST) In-reply-to: <874ll3bo90.fsf@ericabrahamsen.net> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 195.110.48.8 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.21 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" Xref: news.gmane.org gmane.emacs.help:116289 Archived-At: On 2018-03-26, at 03:48, Eric Abrahamsen wrote: > Drew Adams writes: > >>> > But no, way too heavy. I want _one variable_ to persist, and nothing >>> > more. >>> >>> If you already use savehist-mode, you can add your variable to >>> savehist-additional-variables. >> >> There are several possibilities, including these: >> >> 1. `savehist.el' (what Eric said) >> 2. Customize (option value) >> 3. Bookmark (e.g., Bookmark+ variable-list bookmark) >> 4. Desktop >> >> If you only want to save one variable, just use an option. > > To muddy the waters further, there's also eieio-persistent: > > (require 'eieio-base) > (defclass my-var-persister (eieio-persistent) > ((directory > :initarg :directory > :initform "" > :type string))) > > (setq persister (make-instance 'my-var-persister > :directory "~/dir" > :file "~/.emacs.d/persist")) > > (eieio-persistent-save persister) > > ;; Restart Emacs > > (setq persister (eieio-persistent-read "~/.emacs.d/persist")) > > (slot-value persister 'directory) ; "~/.dir" > > > Probably too heavy-weight for what you're describing, but it's another > option. If you ever want to save more complex data than just a single > value, it's not a bad choice. Interesting. Not for one string-valued variable, but worth keeping in mind. Thanks! -- Marcin Borkowski http://mbork.pl