From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: "Perry E. Metzger" Newsgroups: gmane.emacs.devel Subject: Re: [Emacs-diffs] master 938d252 4/4: Make regex matching reentrant; update syntax during match Date: Tue, 19 Jun 2018 13:04:15 -0400 Message-ID: <20180619130415.3e9eb123@jabberwock.cb.piermont.com> References: <20180616204650.8423.73499@vcs0.savannah.gnu.org> <20180616204653.86AFC203CB@vcs0.savannah.gnu.org> <04e89d2beffedcc102b811863910c1ec.squirrel@dancol.org> <20180618115941.4f22a9d3@jabberwock.cb.piermont.com> <1de38eca2662563e9e08006c88a6d2e5.squirrel@dancol.org> <20180619094005.11465a87@jabberwock.cb.piermont.com> <20180619094442.41287e4b@jabberwock.cb.piermont.com> <20180619103002.4f000018@jabberwock.cb.piermont.com> <20180619103325.7d79befb@jabberwock.cb.piermont.com> <9a5f3904-8298-b5e3-cd97-b525f602cc63@dancol.org> <20180619113729.3d1a4c0b@jabberwock.cb.piermont.com> <68752b66-75d2-a732-6ce2-3d8a13b7ff37@cs.ucla.edu> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Trace: blaine.gmane.org 1529427830 8427 195.159.176.226 (19 Jun 2018 17:03:50 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 19 Jun 2018 17:03:50 +0000 (UTC) Cc: Paul Eggert , Daniel Colascione , Stefan Monnier , emacs-devel@gnu.org To: "John Wiegley" Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Jun 19 19:03:45 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fVK2j-00027Z-BX for ged-emacs-devel@m.gmane.org; Tue, 19 Jun 2018 19:03:45 +0200 Original-Received: from localhost ([::1]:43931 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fVK4q-00075E-Jk for ged-emacs-devel@m.gmane.org; Tue, 19 Jun 2018 13:05:56 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:38386) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fVK3H-0006cG-KA for emacs-devel@gnu.org; Tue, 19 Jun 2018 13:04:21 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fVK3E-00085z-Es for emacs-devel@gnu.org; Tue, 19 Jun 2018 13:04:19 -0400 Original-Received: from hacklheber.piermont.com ([166.84.7.14]:58432) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fVK3E-00085n-A0; Tue, 19 Jun 2018 13:04:16 -0400 Original-Received: from snark.cb.piermont.com (localhost [127.0.0.1]) by hacklheber.piermont.com (Postfix) with ESMTP id 9FE3C1AE; Tue, 19 Jun 2018 13:04:15 -0400 (EDT) Original-Received: from jabberwock.cb.piermont.com (jabberwock.cb.piermont.com [10.160.2.107]) by snark.cb.piermont.com (Postfix) with ESMTP id 8BDC62DEC77; Tue, 19 Jun 2018 13:04:15 -0400 (EDT) In-Reply-To: X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 166.84.7.14 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 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.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:226522 Archived-At: On Tue, 19 Jun 2018 09:54:50 -0700 "John Wiegley" wrote: > >>>>> "PE" == Paul Eggert writes: > > PE> If we're going to go to that much work, why not use glibc > PE> regex? It uses a DFA and falls back on backtracking only when > PE> needed. Although glibc regex isn't maintained that well, it's > PE> at least maintained, which TRE is not. And it does have some > PE> advantages: it has an API that is like Emacs src/regex.c, and > PE> it won't have any licensing issues. Its main disadvantage (it > PE> doesn't support split buffers) could be overcome fairly easily, > PE> either by adding support for that back into the library, or > PE> arranging for a single array whenever the regex matcher is > PE> called. > > If we do find a problem with it, how long will it take before the > fix we need is propagated everywhere it needs to go? Which package was the referent for "it"? -- Perry E. Metzger perry@piermont.com