From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.devel Subject: Re: Unbalanced change hooks (part 2) [Documentation fix still remaining] Date: Tue, 30 Aug 2016 17:12:22 +0000 Message-ID: <20160830171222.GA6672@acm.fritz.box> References: <20160811112951.GA2154@acm.fritz.box> <7e1478b6-cf00-fcbf-8c24-43bdaa57e2b6@dancol.org> <415d1cca-f32c-624e-a4be-9aadcf8a0f17@dancol.org> <83inujbpek.fsf@gnu.org> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: blaine.gmane.org 1472577254 21068 195.159.176.226 (30 Aug 2016 17:14:14 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 30 Aug 2016 17:14:14 +0000 (UTC) User-Agent: Mutt/1.5.24 (2015-08-30) Cc: Daniel Colascione , monnier@iro.umontreal.ca, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Aug 30 19:14:09 2016 Return-path: Envelope-to: ged-emacs-devel@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 1bembv-0004pg-NH for ged-emacs-devel@m.gmane.org; Tue, 30 Aug 2016 19:14:07 +0200 Original-Received: from localhost ([::1]:50297 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bembt-0001vJ-6o for ged-emacs-devel@m.gmane.org; Tue, 30 Aug 2016 13:14:05 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:41836) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bemao-0001lb-M3 for emacs-devel@gnu.org; Tue, 30 Aug 2016 13:12:59 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bemah-0006Ht-4S for emacs-devel@gnu.org; Tue, 30 Aug 2016 13:12:57 -0400 Original-Received: from mail.muc.de ([193.149.48.3]:44382) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bemag-0006Hd-UF for emacs-devel@gnu.org; Tue, 30 Aug 2016 13:12:51 -0400 Original-Received: (qmail 15569 invoked by uid 3782); 30 Aug 2016 17:12:48 -0000 Original-Received: from acm.muc.de (p548C605C.dip0.t-ipconnect.de [84.140.96.92]) by colin.muc.de (tmda-ofmipd) with ESMTP; Tue, 30 Aug 2016 19:12:46 +0200 Original-Received: (qmail 6791 invoked by uid 1000); 30 Aug 2016 17:12:22 -0000 Content-Disposition: inline In-Reply-To: <83inujbpek.fsf@gnu.org> X-Delivery-Agent: TMDA/1.1.12 (Macallan) X-Primary-Address: acm@muc.de X-detected-operating-system: by eggs.gnu.org: FreeBSD 9.x X-Received-From: 193.149.48.3 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:206970 Archived-At: Hello, Eli. On Mon, Aug 29, 2016 at 05:50:11PM +0300, Eli Zaretskii wrote: > > From: Daniel Colascione > > Date: Sun, 28 Aug 2016 20:18:32 -0700 > > Please trust me that the documentation misleads. > You are welcome to suggest more accurate wording that describes the > current implementation. I think it's only fair to point out that I did precisly this almost three weeks ago (on 2016-08-10) and the welcome my efforts got was somewhat less than wholeheartedly warm. The current documentation misleads in asserting that b-c-f and a-c-f cannot be used together in balanced pairs. They most assuredly can, with the exception of a tiny number of rarely occurring cases. If this were not true, CC Mode would not work at all. Using b-c-f and a-c-f together is an essential technique - there are things that cannot be done without it, or at least not in any reasonable manner. In this sense, maintaining a duplicate shadow buffer, or scanning from BOB at every buffer change, or maintaining a separate record of all text properties on a buffer, don't fall into the category of reasonable, from my point of view. Eliminating this technique from Emacs, whether by "polluting" the source to stop it working altogether (as suggested by Stefan), or by forbidding it in the documentation, has the effect of making Emacs a less powerful programming system. I don't think this is what any of us should want. [ .... ] -- Alan Mackenzie (Nuremberg, Germany).