From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: martin rudalics Newsgroups: gmane.emacs.devel Subject: Re: Unrecoverable data loss Date: Sun, 18 May 2008 23:25:39 +0200 Message-ID: <48309ED3.3020701@gmx.at> References: <87zlqnqxrl.fsf@escher.local.home> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1211145962 14823 80.91.229.12 (18 May 2008 21:26:02 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 18 May 2008 21:26:02 +0000 (UTC) Cc: emacs-devel@gnu.org To: Stephen Berman Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun May 18 23:26:40 2008 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1JxqOt-0008F4-0A for ged-emacs-devel@m.gmane.org; Sun, 18 May 2008 23:26:39 +0200 Original-Received: from localhost ([127.0.0.1]:55960 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1JxqO8-0005PI-TJ for ged-emacs-devel@m.gmane.org; Sun, 18 May 2008 17:25:52 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1JxqO3-0005O0-QJ for emacs-devel@gnu.org; Sun, 18 May 2008 17:25:47 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1JxqO1-0005KJ-Ao for emacs-devel@gnu.org; Sun, 18 May 2008 17:25:46 -0400 Original-Received: from [199.232.76.173] (port=45325 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1JxqO1-0005K7-3o for emacs-devel@gnu.org; Sun, 18 May 2008 17:25:45 -0400 Original-Received: from mail.gmx.net ([213.165.64.20]:39371) by monty-python.gnu.org with smtp (Exim 4.60) (envelope-from ) id 1JxqO0-0002XJ-HS for emacs-devel@gnu.org; Sun, 18 May 2008 17:25:44 -0400 Original-Received: (qmail invoked by alias); 18 May 2008 21:25:42 -0000 Original-Received: from 62-47-37-109.adsl.highway.telekom.at (EHLO [62.47.37.109]) [62.47.37.109] by mail.gmx.net (mp005) with SMTP; 18 May 2008 23:25:42 +0200 X-Authenticated: #14592706 X-Provags-ID: V01U2FsdGVkX1+HFNtJLZ2H9IpPdfcfOYkOfSwhK1IAmIu8brWR59 jexJwjNhcm422F User-Agent: Mozilla Thunderbird 1.0 (Windows/20041206) X-Accept-Language: de-DE, de, en-us, en In-Reply-To: <87zlqnqxrl.fsf@escher.local.home> X-Y-GMX-Trusted: 0 X-detected-kernel: by monty-python.gnu.org: Linux 2.6 (newer, 3) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:97368 Archived-At: > 5. The inserted text retains the properties in buffer A that it has in > the *Help* buffer, in particular clickable links. Click on the link > displaying the value of the preferred charset, or, if there are text > properties in the description, you can click on one of these links. > (Clicking the link of the value of the code point, or the button > labelled "customize what to show" does not produce the problem.) > > 6. Now buffer A is in Help mode and contains only the Help text of the > clicked link; the text you had previously type is gone. If you type > C-_, Emacs beeps and says "Buffer is read-only". If you toggle the > read-only status and type C-_ again, Emacs beeps again and says "No undo > information in this buffer". If you were typing in a buffer that does > not have auto-save, its contents prior to step 5 is AFAICT unrecoverably > lost. `describe-character-set' uses (with-output-to-temp-buffer (help-buffer) where `help-buffer' is defined as (defun help-buffer () (buffer-name ;for with-output-to-temp-buffer (if help-xref-following (current-buffer) (get-buffer-create "*Help*")))) hence turning your current buffer into a help buffer thus clearing its contents and undo-list, making it read-only, ... Maybe `help-buffer' should refuse to return a buffer if it is not read-only, `buffer-undo-list' is not t, ...