From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: bug-reference-prog-mode slows down CC Mode's scrolling by ~7% Date: Fri, 03 Sep 2021 14:24:31 +0300 Message-ID: <83r1e5yk9c.fsf@gnu.org> References: <83a6kuyysv.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="28967"; mail-complaints-to="usenet@ciao.gmane.io" Cc: monnier@iro.umontreal.ca, emacs-devel@gnu.org To: Alan Mackenzie Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Sep 03 13:54:15 2021 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 1mM7lv-0007Id-Aq for ged-emacs-devel@m.gmane-mx.org; Fri, 03 Sep 2021 13:54:15 +0200 Original-Received: from localhost ([::1]:56866 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mM7lt-0002tP-If for ged-emacs-devel@m.gmane-mx.org; Fri, 03 Sep 2021 07:54:13 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:48426) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mM7JB-00034O-8m for emacs-devel@gnu.org; Fri, 03 Sep 2021 07:24:33 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:56564) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mM7JA-0001pq-8U; Fri, 03 Sep 2021 07:24:32 -0400 Original-Received: from 84.94.185.95.cable.012.net.il ([84.94.185.95]:1403 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mM7J9-0005eD-Rd; Fri, 03 Sep 2021 07:24:32 -0400 In-Reply-To: (message from Alan Mackenzie on Fri, 3 Sep 2021 10:47:41 +0000) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 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:273769 Archived-At: > Date: Fri, 3 Sep 2021 10:47:41 +0000 > Cc: monnier@iro.umontreal.ca, emacs-devel@gnu.org > From: Alan Mackenzie > > > Bother: this is not future-proof, and certainly isn't scalable. If we > > are changing the protocol, can we instead come up with a more scalable > > change, so that functions won't "fight" in the future who gets to be > > "the first"? > > I think we need to be clear about the current situation versus my > proposal. If there is only one element (typically > font-lock-fontify-region) on jit-lock-functions, nothing changes. With > several elements: > > Current situation: The region marked with 'fontified text properties is > the _smallest_ returned by the jit-lock-functions functions. If such a > function returns nil (which is usual), that region becomes precisely > (BEG END), and we lose all the benefit of jit-lock-bounds. > > Proposed mechanism: The region marked with 'fontified is that supplied > by the first j-l-f function, typically font-lock-fontify-region. This > is an enhancement. > > Note that it is difficult to use the jit-lock-bounds returned by a > subsequent function, if they exceed the bounds returned by the first > function. To do this safely, we would have to re-run all the previous > jit-lock-functions on the newly enlarged region. This would be clumsy, > and wouldn't fit in well with our current scheme. > > As for "fighting" to be the first function in j-l-f, I don't think that > should be a problem. We can document the new &optional parameter to > jit-lock-register (not yet implemented) to say "don't use this unless > you really know what you're doing". > > What we have isn't scalable in the sense you mean, and I don't think it > can be made scalable without massive changes in the jit-lock mechanism, > which might well reverse the benefits of using jit-lock-bounds (the 7% > saving in font locking time in CC Mode (and surely other modes, too)). You basically say that you consider what I said not important enough to handle. The only "arguments" you bring up are that you disagree with my assessment. I don't think those are useful arguments, because who said your vision of the future is more accurate than mine? But I don't intend to continue arguing.