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: Emacs design and architecture (was: Shrinking the C core) Date: Fri, 15 Sep 2023 10:30:35 +0300 Message-ID: <83sf7fki5g.fsf@gnu.org> References: <877cpfybhf.fsf@yahoo.com> <873503y66i.fsf@yahoo.com> <87fs3ur9u8.fsf@dataswamp.org> <875y4moiiq.fsf@dataswamp.org> <83r0n4rj78.fsf@gnu.org> <83cyynpmvd.fsf@gnu.org> <838r99mh40.fsf@gnu.org> <83h6nwlmt4.fsf@gnu.org> <456d12ac-ecf4-3de4-56bb-a2440580777f@gutov.dev> <83a5tokmsv.fsf@gnu.org> 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="27818"; mail-complaints-to="usenet@ciao.gmane.io" Cc: dmitry@gutov.dev, owinebar@gmail.com, rms@gnu.org, emacs-devel@gnu.org To: Yuri Khan Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Sep 15 09:31:50 2023 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 1qh3Ir-0006zf-UB for ged-emacs-devel@m.gmane-mx.org; Fri, 15 Sep 2023 09:31:49 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qh3I3-0005ZE-JC; Fri, 15 Sep 2023 03:30:59 -0400 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 1qh3I1-0005Yj-Gc for emacs-devel@gnu.org; Fri, 15 Sep 2023 03:30:57 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qh3I1-00072W-3X; Fri, 15 Sep 2023 03:30:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=gnu.org; s=fencepost-gnu-org; h=MIME-version:References:Subject:In-Reply-To:To:From: Date; bh=5gZDFudMkc4azrmV2GjWAS0vTvlkcLoS/cCATpJiCmY=; b=GegolfrOIQGjmgLaaIwQ KI2bGPyhj7yMPSsUVFPkfbiHg1ZmyWxxaHyIFoUwYfwiVhdeYNsEaBLYtzVLQesPSLVb3ruMxr527 jBNcMdNg8GaK9Br+c+gJi7KRlULIg/XJ/hC1E4zQ/7j2MZOJO3n6I+xIRGUHID9cMVu8WsUxZcXzq De7V75u6AUxhqSxpBDGYcsoTfOgXgdDbM0Q3vArB7FW2xuPfSIb7zjm5/mVkIWDmqhoGtoJmYV1Io d4J+iPfFF3r/ancwiEEKQesQ3OFHt9mUIsDn50fbPJ2J1l/3PHufwu9weaqUIQaOvoOtGRQJBnANB cYvGLbieqsOl5A==; In-Reply-To: (message from Yuri Khan on Fri, 15 Sep 2023 13:51:56 +0700) 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-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:310594 Archived-At: > From: Yuri Khan > Date: Fri, 15 Sep 2023 13:51:56 +0700 > Cc: Dmitry Gutov , owinebar@gmail.com, rms@gnu.org, emacs-devel@gnu.org > > On Fri, 15 Sept 2023 at 12:51, Eli Zaretskii wrote: > > > One of the important aspects to keep in mind in this regard is that > > Emacs must give Lisp programs dynamic control of how stuff is > > displayed, and should be able to exercise that control at high > > frequency (a trivial example: pulse.el). > > In CSS, this is solved in core with transitions. A style specifies > that a certain property will change gradually, provides its target > value, the transition duration, and a transition curve. You have taken the pulse.el example too literally. The fact that it changes the color gradually is not relevant to the point I was trying to make, but you made it the main point. My point is that quite a few Lisp programs affect the display in near-real time and at high frequency. This is what makes Emacs so powerful, and we don't want to lose this power when changing the display engine. > The use case of pulse.el would be translated to a couple of styles > that say effectively “A pulsed span will instantly gain yellow > background” and “A non-pulsed span will linearly revert to whatever > background it had over the course of 200 milliseconds” and a small > function that sets the span to pulsed and then immediately to > non-pulsed. This sounds like a lot of hair, when a Lisp program just wants to change the color of some part of the display. > (Implementing a CSS engine over a character terminal is a nontrivial > matter though.) Something else to keep in mind, I guess. TTY colors are implemented specially and separately in Emacs (under the hood; Lisp programs can disregard the differences if they want), so it isn't a non-starter, per se.