From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.bugs Subject: bug#17139: Race condition in complete-in-region: should we be using pre-command-hook, not post-command-hook? Date: Mon, 31 Mar 2014 08:40:04 -0400 Message-ID: References: <53362D5C.2070502@dancol.org> <53363260.9060207@dancol.org> <53389187.3090901@dancol.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1396269694 27703 80.91.229.3 (31 Mar 2014 12:41:34 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 31 Mar 2014 12:41:34 +0000 (UTC) Cc: 17139@debbugs.gnu.org To: Daniel Colascione Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Mon Mar 31 14:41:27 2014 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1WUbWo-0005eT-SE for geb-bug-gnu-emacs@m.gmane.org; Mon, 31 Mar 2014 14:41:26 +0200 Original-Received: from localhost ([::1]:48506 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WUbWo-0001sZ-G6 for geb-bug-gnu-emacs@m.gmane.org; Mon, 31 Mar 2014 08:41:26 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:50137) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WUbWd-0001sA-II for bug-gnu-emacs@gnu.org; Mon, 31 Mar 2014 08:41:23 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WUbWR-0003A6-QF for bug-gnu-emacs@gnu.org; Mon, 31 Mar 2014 08:41:15 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:56483) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WUbWR-00039z-Mh for bug-gnu-emacs@gnu.org; Mon, 31 Mar 2014 08:41:03 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1WUbWR-0001uX-As for bug-gnu-emacs@gnu.org; Mon, 31 Mar 2014 08:41:03 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Monnier Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Mon, 31 Mar 2014 12:41:03 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 17139 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 17139-submit@debbugs.gnu.org id=B17139.13962696167272 (code B ref 17139); Mon, 31 Mar 2014 12:41:03 +0000 Original-Received: (at 17139) by debbugs.gnu.org; 31 Mar 2014 12:40:16 +0000 Original-Received: from localhost ([127.0.0.1]:57665 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WUbVe-0001tD-TH for submit@debbugs.gnu.org; Mon, 31 Mar 2014 08:40:15 -0400 Original-Received: from chene.dit.umontreal.ca ([132.204.246.20]:51449) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WUbVY-0001sw-Pt for 17139@debbugs.gnu.org; Mon, 31 Mar 2014 08:40:09 -0400 Original-Received: from pastel.home (lechon.iro.umontreal.ca [132.204.27.242]) by chene.dit.umontreal.ca (8.14.1/8.14.1) with ESMTP id s2VCeR2Z025682; Mon, 31 Mar 2014 08:40:27 -0400 Original-Received: by pastel.home (Postfix, from userid 20848) id 5D1F6604C6; Mon, 31 Mar 2014 08:40:04 -0400 (EDT) In-Reply-To: <53389187.3090901@dancol.org> (Daniel Colascione's message of "Sun, 30 Mar 2014 14:49:59 -0700") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3.50 (gnu/linux) X-NAI-Spam-Flag: NO X-NAI-Spam-Threshold: 5 X-NAI-Spam-Score: 0 X-NAI-Spam-Rules: 1 Rules triggered RV4898=0 X-NAI-Spam-Version: 2.3.0.9362 : core <4898> : inlines <664> : streams <1148397> : uri <1715862> X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 140.186.70.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:87567 Archived-At: > Come to think of it, supplying a function instead of a simple list of > strings as the completion table returned from the completion function > would probably help too, since then completion-in-region--postch could > inspect the first element of the returned list (the completion region > start) without having to actually "force the promise" and resolve the > whole list after every command. Exactly: completion-in-region--postch does not need to know the candidates. If you need a subprocess to get the list of candidates, then foo-at-point-function is usually not the right place/time to build this list, you should use completion-table-dynamic, completion-table-with-cache, or something like that instead. Some foo-at-point-function get away with building the list directly, but then caching it so that subsequent calls (e.g. via completion-in-region--postch) don't need to contact the subprocess again. Of course, there could be cases where the star&end positions are themselves computed by a subprocess, in which case completion-in-region--postch would have to contact the subprocess. Stefan