From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.devel Subject: Re: CC Mode with font-lock-maximum-decoration 2 Date: Mon, 8 Aug 2022 19:09:50 +0000 Message-ID: References: <83pmhcvugm.fsf@gnu.org> <83czdbwjfr.fsf@gnu.org> <837d3jvu9f.fsf@gnu.org> <83sfm6veqa.fsf@gnu.org> <83pmhavdim.fsf@gnu.org> <83o7wuva9o.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="6607"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Aug 08 21:11:52 2022 Return-path: Envelope-to: ged-emacs-devel@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 1oL8AK-0001Wq-CD for ged-emacs-devel@m.gmane-mx.org; Mon, 08 Aug 2022 21:11:52 +0200 Original-Received: from localhost ([::1]:57464 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oL8AI-0004M5-Ph for ged-emacs-devel@m.gmane-mx.org; Mon, 08 Aug 2022 15:11:50 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:33352) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oL88S-0003O4-AY for emacs-devel@gnu.org; Mon, 08 Aug 2022 15:09:56 -0400 Original-Received: from colin.muc.de ([193.149.48.1]:19576 helo=mail.muc.de) by eggs.gnu.org with smtp (Exim 4.90_1) (envelope-from ) id 1oL88Q-000653-BJ for emacs-devel@gnu.org; Mon, 08 Aug 2022 15:09:56 -0400 Original-Received: (qmail 36468 invoked by uid 3782); 8 Aug 2022 19:09:51 -0000 Original-Received: from acm.muc.de (p4fe1582e.dip0.t-ipconnect.de [79.225.88.46]) (using STARTTLS) by colin.muc.de (tmda-ofmipd) with ESMTP; Mon, 08 Aug 2022 21:09:51 +0200 Original-Received: (qmail 8329 invoked by uid 1000); 8 Aug 2022 19:09:50 -0000 Content-Disposition: inline In-Reply-To: <83o7wuva9o.fsf@gnu.org> X-Submission-Agent: TMDA/1.3.x (Ph3nix) X-Primary-Address: acm@muc.de Received-SPF: pass client-ip=193.149.48.1; envelope-from=acm@muc.de; helo=mail.muc.de 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_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 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-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:293282 Archived-At: Hello, Eli. On Mon, Aug 08, 2022 at 21:51:47 +0300, Eli Zaretskii wrote: > > Date: Mon, 8 Aug 2022 18:41:01 +0000 > > Cc: emacs-devel@gnu.org > > From: Alan Mackenzie > > > And btw, I'm not sure I understand what you are saying. Are you > > > saying that level 2 is enough for fontifications in C mode? > > No. > > > If so, what are we losing when compared to the value t, and if we don't > > > lose anything important, why do we need any fontifications beyond what > > > level 2 gives us? > > We lose accuracy. That is important to a lot of people, including the > > many who have sent in bug reports because of lack of accuracy. > Then what is the importance of these measurements of yours? They show that an attempt to speed up CC Mode/2 should be concentrating on the code which isn't fontification code. > The fact that at level 2 C mode is only slightly slower than Lisp mode > is therefore purely academic: you don't expect anyone to use it, and > don't recommend using it. The _FONTIFICATION_ of CC Mode/2 is only a little slower than that of Emacs Lisp Mode. Reports from you show that the mode as a whole is too slow. I do expect people to use it, those for whom lightning fast response is more important than accuracy. I just don't think these users constitute a majority. > > > For Lisp, btw, the difference between level 2 and t is negligible. > > > And the same goes for most/all other modes, which is the reason why we > > > have set the value to t years ago. I'm quite sure at that time the > > > difference between 2 and t for C mode was also very small. > > Martin Stjernholm wrote (what has become) the current level 3 around 20 > > years ago, noting specifically it was expected to be slower than before, > > and that the new level 2 was comparable in both speed and accuracy to the > > old level 3. Since then level 3 has become considerably more accurate > > and quite a bit slower, too. > That's almost certainly what happened. -- Alan Mackenzie (Nuremberg, Germany).