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: Is it possible to save undo state in file and reload again? Date: Fri, 06 Jan 2023 18:24:41 +0300 Message-ID: <0357584ce5b79f1e9f0c303f22901b06.support1@rcdrun.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="3235"; mail-complaints-to="usenet@ciao.gmane.io" To: Help GNU Emacs Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Fri Jan 06 16:25:44 2023 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 1pDobG-0000az-IN for geh-help-gnu-emacs@m.gmane-mx.org; Fri, 06 Jan 2023 16:25:42 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pDoar-0006ZM-3F; Fri, 06 Jan 2023 10:25:17 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pDoan-0006Vu-QN for help-gnu-emacs@gnu.org; Fri, 06 Jan 2023 10:25:14 -0500 Original-Received: from stw1.rcdrun.com ([217.170.207.13]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pDoam-0004ue-53 for help-gnu-emacs@gnu.org; Fri, 06 Jan 2023 10:25:13 -0500 Original-Received: from localhost ([::ffff:197.239.40.106]) (AUTH: PLAIN admin, TLS: TLS1.3,256bits,ECDHE_RSA_AES_256_GCM_SHA384) by stw1.rcdrun.com with ESMTPSA id 0000000000055D56.0000000063B83D5A.00001C2F; Fri, 06 Jan 2023 08:25:14 -0700 Received-SPF: pass client-ip=217.170.207.13; envelope-from=support1@rcdrun.com; helo=stw1.rcdrun.com X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.25, 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: 2.1.29 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-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.help:142133 Archived-At: There must exist some "undo" state in Emacs for {C-x u} to work, right? Is it maybe the contents of variable `pending-undo-list'? I have tried saving it this way: (defun data-to-file (data file) "PRIN1 Emacs Lisp DATA to FILE" (string-to-file-force (prin1-to-string data) file)) (defun data-from-file (file) "Reads and returns Emacs Lisp data from FILE" (condition-case nil (car (read-from-string (file-to-string file))) (error nil))) (data-to-file pending-undo-list "pul") ➜ "pul" (file-to-string "pul") works and I can see what is inside. But then my function `data-from-file' can't handle it: (data-from-file "pul") because I get this error (read-from-string (file-to-string "pul")) eval: Invalid read syntax: "#" How can I save it in file and read from file with that read syntax "#"? It should be somehow possible. When editing database objects I would try to capture the undo state and at any new editing to reload the undo state. -- Jean Take action in Free Software Foundation campaigns: https://www.fsf.org/campaigns In support of Richard M. Stallman https://stallmansupport.org/