From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: Patch for lookaround assertion in regexp Date: Mon, 23 Jan 2012 12:11:26 -0500 Message-ID: References: <009001ccd9c0$9bde09f0$d39a1dd0$@cfraizer.com> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1327338696 16347 80.91.229.12 (23 Jan 2012 17:11:36 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Mon, 23 Jan 2012 17:11:36 +0000 (UTC) Cc: Tom , emacs-devel@gnu.org To: Andreas Schwab Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Jan 23 18:11:32 2012 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([140.186.70.17]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1RpNQZ-0008Hu-LQ for ged-emacs-devel@m.gmane.org; Mon, 23 Jan 2012 18:11:31 +0100 Original-Received: from localhost ([::1]:45257 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RpNQZ-0002Dt-70 for ged-emacs-devel@m.gmane.org; Mon, 23 Jan 2012 12:11:31 -0500 Original-Received: from eggs.gnu.org ([140.186.70.92]:37256) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RpNQW-0002AF-Iq for emacs-devel@gnu.org; Mon, 23 Jan 2012 12:11:29 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RpNQV-0007Xz-Me for emacs-devel@gnu.org; Mon, 23 Jan 2012 12:11:28 -0500 Original-Received: from ironport2-out.teksavvy.com ([206.248.154.181]:36457) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RpNQV-0007Xt-J1 for emacs-devel@gnu.org; Mon, 23 Jan 2012 12:11:27 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Av0EAFWTHU9MCos2/2dsb2JhbABDrieBBoFyAQEEAVYjBQsLNBIUGA0kiA+4N4wmBIg7mnOEVw X-IronPort-AV: E=Sophos;i="4.71,556,1320642000"; d="scan'208";a="158249932" Original-Received: from 76-10-139-54.dsl.teksavvy.com (HELO pastel.home) ([76.10.139.54]) by ironport2-out.teksavvy.com with ESMTP/TLS/ADH-AES256-SHA; 23 Jan 2012 12:11:26 -0500 Original-Received: by pastel.home (Postfix, from userid 20848) id 6763A58D29; Mon, 23 Jan 2012 12:11:26 -0500 (EST) In-Reply-To: (Andreas Schwab's message of "Mon, 23 Jan 2012 17:14:49 +0100") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.92 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 206.248.154.181 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:147856 Archived-At: >> If it doesn't then it's a job for the translation layer. Char syntaxes >> and categories could be converted into the standard [...] format. > Enumerating the syntax/category members is not an option. Indeed. > There is no easy way to do that. For `categories', there is a way, but the result is a *very* large [...] chunk, so it's impractical. For `syntax' there is indeed no way, since the syntax of a char doesn't only depend on the char itself but also of the `char-table' text-property that might be applied to that particular character position (and of course, if we ignore this problem, we're still back to the same problem of enormous [...] expressions, as is the case for categories). These entities really need to be implemented inside the regexp-engine (but they're usually pretty easy to implement there). Stefan