From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Daniel Colascione Newsgroups: gmane.emacs.devel Subject: Re: cc-mode fontification feels random Date: Thu, 10 Jun 2021 00:01:38 -0700 Message-ID: <179f4b9f450.2816.cc5b3318d7e9908e2c46732289705cb0@dancol.org> References: <73ff18bf-66dc-7d7a-a0db-8edc2cdceba8@gmx.at> <83o8cge4lg.fsf@gnu.org> <62e438b5-d27f-1d3c-69c6-11fe29a76d74@dancol.org> <83fsxsdxhu.fsf@gnu.org> <179f22a44d8.2816.cc5b3318d7e9908e2c46732289705cb0@dancol.org> Mime-Version: 1.0 Content-Type: text/plain; format=flowed; charset="us-ascii" Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="4076"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: AquaMail/1.29.2-1810 (build: 102900008) Cc: rudalics@gmx.at, Eli Zaretskii , rms@gnu.org, emacs-devel@gnu.org To: Stefan Monnier , Alan Mackenzie Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Jun 10 09:04:17 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 1lrEjh-0000sw-Ci for ged-emacs-devel@m.gmane-mx.org; Thu, 10 Jun 2021 09:04:17 +0200 Original-Received: from localhost ([::1]:36974 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lrEjg-0007cT-8H for ged-emacs-devel@m.gmane-mx.org; Thu, 10 Jun 2021 03:04:16 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:59424) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lrEhM-0005yO-3D for emacs-devel@gnu.org; Thu, 10 Jun 2021 03:01:52 -0400 Original-Received: from dancol.org ([2600:3c01:e000:3d8::1]:56910) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lrEhG-0008EN-Lr; Thu, 10 Jun 2021 03:01:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=dancol.org; s=x; h=Content-Transfer-Encoding:Content-Type:MIME-Version:Subject: References:In-Reply-To:Message-ID:Date:CC:To:From:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=MJ0ClJ37AVi/gSRndRFqODgWjZO7A737kV1UsO1H3ow=; b=ZKi+KSj45vxM/4PhG3u5Lvt29M uIP5/WAPCVTsYThwknq9WWr8eD8uQsKyCSaP3s0Ywto20XNKxtHcQqF+F2hS4AFu6FVTRE33aEGEe Uv8TjLYK+RPQrCPkpUgORrELXi3mTSpRacBMnkNeIzRoAKi1RZfmQOh/VXnRqE+1hWFfZ6TUNZO/2 kexIb8N6Ah3JISHzm8LCAO7OewyveFwQLP3VnH9KIISmofqoyzQ10ZD3OweIq2asrgaRG9SNjzvYP 16OxnaeovuXK8JJ8JS/VKhGglZ6/qItXbpvuf7P4HcX5XAA7YvebTEN5qHtofflA7AawQeTUURmsh 5WKW3PZg==; Original-Received: from 195.sub-174-193-168.myvzw.com ([174.193.168.195]:5762 helo=[100.93.253.121]) by dancol.org with esmtpsa (TLS1.2:ECDHE_RSA_CHACHA20_POLY1305:256) (Exim 4.89) (envelope-from ) id 1lrEhA-00042w-JX; Thu, 10 Jun 2021 00:01:40 -0700 In-Reply-To: Received-SPF: pass client-ip=2600:3c01:e000:3d8::1; envelope-from=dancol@dancol.org; helo=dancol.org X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 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, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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:270632 Archived-At: On June 9, 2021 1:36:42 PM Stefan Monnier wrote: >> That's a rather negative way of putting things, which is a bit indefinite >> and wishy-washy. You could instead try to specify which tokens should get >> font-lock-type-face and which shouldn't, thus giving something concrete >> to discuss. I think this will be difficult to do well, and may lead to >> the result which I alluded to above. > > It has to be said also that C/C++ is quite unusual in that knowing which > identifier is a type is necessary for correct parsing. If it weren't > so, we could reliably highlight types not based on their name but based > on their location in the syntax. > > I think an approach like that of tree-sitter should be able (at least in > theory) to give reasonably good highlighting of types based on their > position (tho sadly not in those cases where the syntax is ambiguous). The model I've had in mind for dealing with parse ambiguity is an incremental GLR parser generating a parse forest, pruning the forest by constraint solving on ad-hoc language specific constraints, then picking one of the remaining parse trees incrementally to fontify.