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: How to add pseudo vector types Date: Sat, 17 Jul 2021 20:54:56 +0300 Message-ID: <831r7w4yhb.fsf@gnu.org> References: <83h7gw6pyj.fsf@gnu.org> <45EBF16A-C953-42C7-97D1-3A2BFEF7DD01@gmail.com> <83y2a764oy.fsf@gnu.org> <83v95b60fn.fsf@gnu.org> <00DD5BFE-D14E-449A-9319-E7B725DEBFB3@gmail.com> <83r1fz5xr9.fsf@gnu.org> <1AAB1BCC-362B-4249-B785-4E0530E15C60@gmail.com> <83czri67h0.fsf@gnu.org> <46BBFF88-76C3-4818-8805-5437409BEA93@gmail.com> <83wnpq46uk.fsf@gnu.org> <533BD53B-4E85-4E9E-B46A-346A5BBAD0F5@gmail.com> <258CB68D-1CC1-42C8-BDCD-2A8A8099B783@gmail.com> <1a776770-50b7-93cd-6591-c9a5b3a56eb8@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="33238"; mail-complaints-to="usenet@ciao.gmane.io" Cc: cpitclaudel@gmail.com, emacs-devel@gnu.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sat Jul 17 19:56:08 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 1m4oXo-0008Vc-Bx for ged-emacs-devel@m.gmane-mx.org; Sat, 17 Jul 2021 19:56:08 +0200 Original-Received: from localhost ([::1]:47906 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m4oXn-0001Bh-DN for ged-emacs-devel@m.gmane-mx.org; Sat, 17 Jul 2021 13:56:07 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:57034) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m4oXE-0000CB-B2 for emacs-devel@gnu.org; Sat, 17 Jul 2021 13:55:32 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:52746) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m4oXC-0002Lo-RG; Sat, 17 Jul 2021 13:55:30 -0400 Original-Received: from 84.94.185.95.cable.012.net.il ([84.94.185.95]:4259 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 1m4oWr-0000hA-Og; Sat, 17 Jul 2021 13:55:28 -0400 In-Reply-To: (message from Stefan Monnier on Sat, 17 Jul 2021 13:30:40 -0400) 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:271340 Archived-At: > From: Stefan Monnier > Cc: emacs-devel@gnu.org > Date: Sat, 17 Jul 2021 13:30:40 -0400 > > Clément said: > > I have no idea if it makes sense, but: does the initial parse need to be > > synchronous, or could you instead run the parsing in one thread, and the > > rest of Emacs in another? (I'm talking about concurrent execution, not > > cooperative threading). > > If we copy the buffer's content to a freshly malloc area before passing > that to TS, then there should be no problem running TS in a separate > concurrent thread, indeed. Making a copy of the buffer is a non-starter from where I stand. It doesn't scale, for starters. I don't see any reason to go to such a complex design at this early stage. > Eli said: > > Why do you update the entire parser list for every modification? > > This comment: > > If having multiple parsers in a single buffer is a not-uncommon case, > then indeed we'll need to do better, but if we assume this is an > anomalous situation, then Yuan's code is optimal ;-) > > > Yes, I think we should only ask TS to parse what we need, not more. > > We'll need to experiment with that. We can experiment, but I think the basic design should be clean and reasonable from the get-go. > Using an approach like `syntax-ppss` where we only parse up to some > high-watermark might be a good approach, but it's also possible that > it will work poorly: if TS assumes it works on the whole buffer, > then it will see the truncated text as a syntax error and while it > is supposed to handle syntax errors nicely it may still lead to > suboptimal behavior when parts of perfectly valid code is misparsed > because the parser was not allowed to see the closing braces that > make it "perfectly valid". TS must be able to handle these situation well enough, because they happen during editing all the time. I wouldn't worry about that, definitely not at this stage. Different uses of the parse results will need to pass different chunks of buffer text, and that is okay.