From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.help Subject: Re: cl-dolist, dolist, cl-return, Date: Fri, 10 Jul 2015 12:57:27 -0400 Message-ID: References: <87fv4za4jo.fsf@nl106-137-147.student.uu.se> <87k2ub2bgb.fsf@nl106-137-147.student.uu.se> <87oajmi6eh.fsf@nl106-137-147.student.uu.se> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1436547488 16169 80.91.229.3 (10 Jul 2015 16:58:08 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 10 Jul 2015 16:58:08 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Fri Jul 10 18:58:00 2015 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 1ZDbcd-00082M-OF for geh-help-gnu-emacs@m.gmane.org; Fri, 10 Jul 2015 18:57:59 +0200 Original-Received: from localhost ([::1]:45480 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZDbcc-0001NM-Vs for geh-help-gnu-emacs@m.gmane.org; Fri, 10 Jul 2015 12:57:58 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:33236) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZDbcQ-0001NB-2J for help-gnu-emacs@gnu.org; Fri, 10 Jul 2015 12:57:46 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZDbcM-0006HE-TT for help-gnu-emacs@gnu.org; Fri, 10 Jul 2015 12:57:46 -0400 Original-Received: from plane.gmane.org ([80.91.229.3]:41409) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZDbcM-0006H2-Mk for help-gnu-emacs@gnu.org; Fri, 10 Jul 2015 12:57:42 -0400 Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1ZDbcK-0007qP-8q for help-gnu-emacs@gnu.org; Fri, 10 Jul 2015 18:57:40 +0200 Original-Received: from 157-52-6-103.cpe.teksavvy.com ([157.52.6.103]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 10 Jul 2015 18:57:40 +0200 Original-Received: from monnier by 157-52-6-103.cpe.teksavvy.com with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 10 Jul 2015 18:57:40 +0200 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 12 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: 157-52-6-103.cpe.teksavvy.com User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux) Cancel-Lock: sha1:P8kO62G7hOCUQKZnlgo4vMfvGok= 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:105582 Archived-At: > But I'm not using nth - probably you misread "neq". No, I'm talking about the code used internally by dolist. If the list over which we iterate were re-computed each time, then to find the "next" element, we'd need to use nth at each iteration. IOW it's a different problem from the re-computation of array bounds at each iteration (which would be inefficient in itself but wouldn't impose additional inefficiencies on the rest of the loop). Stefan