From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Thorsten Jolitz Newsgroups: gmane.emacs.help Subject: Re: regexp question: match anything but not a group? Date: Thu, 03 Apr 2014 12:50:43 +0200 Message-ID: <87r45eit4s.fsf@gmail.com> References: <87zjk4louc.fsf@gmail.com> <533BC538.7010906@easy-emacs.de> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: ger.gmane.org 1396533327 4252 80.91.229.3 (3 Apr 2014 13:55:27 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 3 Apr 2014 13:55:27 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Thu Apr 03 15:55:21 2014 Return-path: Envelope-to: geh-help-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 1WVhpE-0007De-RE for geh-help-gnu-emacs@m.gmane.org; Thu, 03 Apr 2014 15:37:00 +0200 Original-Received: from localhost ([::1]:44106 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WVhpE-0005jX-E9 for geh-help-gnu-emacs@m.gmane.org; Thu, 03 Apr 2014 09:37:00 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:59288) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WVhoP-0004wc-94 for help-gnu-emacs@gnu.org; Thu, 03 Apr 2014 09:36:14 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WVhoJ-00015N-Mj for help-gnu-emacs@gnu.org; Thu, 03 Apr 2014 09:36:09 -0400 Original-Received: from plane.gmane.org ([80.91.229.3]:46426) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WVhoJ-00015I-FL for help-gnu-emacs@gnu.org; Thu, 03 Apr 2014 09:36:03 -0400 Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1WVglF-0005ng-7t for help-gnu-emacs@gnu.org; Thu, 03 Apr 2014 14:28:49 +0200 Original-Received: from e178191011.adsl.alicedsl.de ([85.178.191.11]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 03 Apr 2014 14:28:49 +0200 Original-Received: from tjolitz by e178191011.adsl.alicedsl.de with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 03 Apr 2014 14:28:49 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 88 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: e178191011.adsl.alicedsl.de User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) Cancel-Lock: sha1:3ksn/5Bk646+LYnNZ2rSydde1tQ= X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 80.91.229.3 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:96935 Archived-At: Andreas Röhler writes: > Am 01.04.2014 23:30, schrieb Thorsten Jolitz: >> >> Hi List, >> >> how can I write a regexp that acts like e.g. >> >> ,------ >> | ".*?" >> `------ >> >> but does not match a group like e.g. >> >> ,--------------------- >> | (regexp-quote "\\)") >> `--------------------- >> >> ? >> >> This works more or less but does not seem to be very robust >> >> ,--------- >> | "[^)]*?" >> `--------- >> >> since ')' could appear in other contexts than the group. How can I >> negate a specific group of characters and not only any occurence of >> single characters? >> > > > You need look-ahead-assertions, which aren't implemented in Emacs AFAIK. > Here is a workaround to play with: > > (progn > (and (looking-at ".*") > (not (eq (char-after) ?\)))) > (message "%s" (match-string-no-properties 0))) > > Test with more than one char ahead writing n char-after: > > (not (eq (char-after (+ 1 (point)) MY-CHAR))) > (not (eq (char-after (+ 2 (point)) MY-CHAR))) Since gmane.org was down sometime, this thread was continued with PMs, so, just for reference, here is my solution to an extended form of the original problem (i.e. determine if a given regexp is a regexp group or not): ,------------------------------------------------------- | Andreas Röhler writes: | | > Which would extend the question... | > You wanted not to match any | > | > (regexp-quote "\\)") | | I think I got it: | | #+begin_src emacs-lisp | (defun tj/regexp-group-p (rgxp) | "Return RGXP if its a regexp group, nil otherwise." | (with-temp-buffer | (insert (format "%S" rgxp)) | (goto-char (point-min)) | (if (ignore-errors | (save-excursion | (and | (re-search-forward "(") | (save-match-data | (looking-back | (concat "^" (regexp-quote "\"\\\\(")) | (line-beginning-position))) | (goto-char (match-beginning 0)) | (progn | (forward-sexp) | (looking-at | "[*+]?[?]?\"$"))))) | rgxp nil))) | #+end_src | | Thanks for you help! `------------------------------------------------------- -- cheers, Thorsten