From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Ihor Radchenko Newsgroups: gmane.emacs.devel Subject: Re: Emacs design and architecture. How about copy-on-write? Date: Fri, 22 Sep 2023 15:49:21 +0300 Message-ID: <87wmwiwey6.fsf@localhost> References: <877conk5ny.fsf@localhost> <83ttrreeu0.fsf@gnu.org> <87bkdzeas1.fsf@localhost> <83cyyfe5l8.fsf@gnu.org> <87led2o0nb.fsf@localhost> <83ttrqcpfb.fsf@gnu.org> <877comnv4a.fsf@localhost> <83fs3ackrq.fsf@gnu.org> <99e84ae7-b3aa-a009-5cb8-a75826343196@gutov.dev> <838r92cgxp.fsf@gnu.org> <837comcam8.fsf@gnu.org> <6946e6f0-c6ef-186c-35d4-c09935c05a07@gutov.dev> <83y1h1axtq.fsf@gnu.org> <87cyyd8487.fsf@localhost> <83il84c3p4.fsf@gnu.org> <87pm2bzu33.fsf@localhost> <831qerac81.fsf@gnu.org> <87pm2ay13w.fsf@localhost> <83o7hu77bm.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="28731"; mail-complaints-to="usenet@ciao.gmane.io" Cc: dmitry@gutov.dev, acm@muc.de, incal@dataswamp.org, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Fri Sep 22 14:49:00 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 1qjfad-0007EC-Tr for ged-emacs-devel@m.gmane-mx.org; Fri, 22 Sep 2023 14:49:00 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qjfZw-0006u6-Le; Fri, 22 Sep 2023 08:48:17 -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 1qjfZs-0006tc-0f for emacs-devel@gnu.org; Fri, 22 Sep 2023 08:48:12 -0400 Original-Received: from mout01.posteo.de ([185.67.36.65]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qjfZp-0006VF-1q for emacs-devel@gnu.org; Fri, 22 Sep 2023 08:48:11 -0400 Original-Received: from submission (posteo.de [185.67.36.169]) by mout01.posteo.de (Postfix) with ESMTPS id B4C85240028 for ; Fri, 22 Sep 2023 14:48:06 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=posteo.net; s=2017; t=1695386886; bh=EoaUSp+wbaFWsOxgEirCpMZEbh0IP67UNtXgnPcwI20=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:From; b=gjBmw+CnJvEUkCrMhhUKVNrWVKxXv0GT+TudWANa4CHpZBeKKSIuftRGWTzJab32U Yg9SvvEZ09InY6EiTdmxp+glpwyKx+mCJdoIDDXfue/QcB05XJJ1QI6QL3WbuP+YR8 4HEeFAiEhb9PgXvj3uPjpfzBVmJ1r1aEpbL9pUQBb1jN0zTZeG7ffMhRyaSJf/XWG/ 4GUgVTpbzEAMGiVKegcByONMUuRCZogGzUEL2a1/Cmy5kROu9P+m3lX7gFjza1Rj86 NmM9MZccjc4GFdmE8P9zNfeLTU80WpORsNRVNB0jgWRH8i3p436GHAApKUhKDlCoFN 7hs6w5H+e/gZg== Original-Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4RsX9x5ymXz6twr; Fri, 22 Sep 2023 14:48:05 +0200 (CEST) In-Reply-To: <83o7hu77bm.fsf@gnu.org> Received-SPF: pass client-ip=185.67.36.65; envelope-from=yantar92@posteo.net; helo=mout01.posteo.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.devel:310956 Archived-At: Eli Zaretskii writes: >> > compute_stop_pos finds the next "stop position" where properties (or >> > something else of interest to redisplay) change, and when the >> > iteration gets to that position, handle_stop calls the available >> > handler methods to do their thing. The intervals of the text >> > properties are examined by compute_stop_pos. >> >> Thanks! >> "stop position" is not triggered by _all_ the properties though. >> `compute_stop_pos' calculates the largest region where the properties >> listed in `it_props' ('fontified, 'face, 'invisible, and 'composition) >> remain the same. If any other property not in the list changes, it is >> ignored (except `char-property-alias-alist' which may link other >> properties to 'fontified/face/invisible/composition). > > Does this contradict what I wrote? if so, how? Does not contradict, but adds some details. IMHO, it is important that not _a_ property should change to "stop". But one of a small set of properties. I did not write this to argue about your statement. Just to get a reply if I missed something when reading the code. >> Further, handle_stop handlers do search for their corresponding handled >> property via Fnext_single_property_change, which again iterates over >> every interval in the buffer until that single property value changes. > > If they do this, it's because they need that to do their thing. > There's no requirement from the handlers to do that. Moreover, we > could record the position of the next change of each property, when > the handler does determine that, and use that in compute_stop_pos, to > avoid repeating the same search. That might indeed be one possible optimization. >> I believe that having a more efficient algorithm to detect where a >> single property change should speed things up significantly. handle_stop >> will benefit directly, while `compute_stop_pos' could query >> min (mapcar (Fnext_single_property_change, it_props)) >> to avoid counting unrelated properties. > > Feel free to present such a more efficient algorithm, and thanks. > And I'm not sure I understand why you think that > > min (mapcar (Fnext_single_property_change, it_props)) > > will be cheaper than the current algorithm in compute_stop_pos, since > Fnext_single_property_change basically examines the same intervals > again and again for each property in it_props. The algorithm I have in mind is to change interval tree to store several trees together - a common tree storing segments delimited by _a_ property change + a tree for individual properties. That way, looking up for next single property change will be a simple call to next_interval for the property itself + property aliases. -- Ihor Radchenko // yantar92, Org mode contributor, Learn more about Org mode at . Support Org development at , or support my work at