From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Emanuel Berg Newsgroups: gmane.emacs.help Subject: Re: side effects, list sharing [was: `append' vs. `nconc'] Date: Fri, 01 Jan 2016 14:20:45 +0100 Message-ID: <87r3i1tp02.fsf@debian.uxu> References: <568164D8.6050700@ojkastl.de> <87io3iyr7t.fsf@debian.uxu> <87si2kezg1.fsf@mithlond.arda> <87a8osrlj4.fsf_-_@debian.uxu> <87lh8bgafa.fsf@mithlond.arda> <87r3i3ch63.fsf@kuiper.lan.informatimago.com> <87si2jqee2.fsf@debian.uxu> <20151231093045.GB19900@tuxteam.de> <8760zev3xt.fsf@debian.uxu> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1451654492 852 80.91.229.3 (1 Jan 2016 13:21:32 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 1 Jan 2016 13:21:32 +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 Jan 01 14:21:24 2016 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 1aEzdz-00060o-9a for geh-help-gnu-emacs@m.gmane.org; Fri, 01 Jan 2016 14:21:23 +0100 Original-Received: from localhost ([::1]:35919 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aEzdv-00008A-Af for geh-help-gnu-emacs@m.gmane.org; Fri, 01 Jan 2016 08:21:19 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:42104) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aEzdk-00007x-N2 for help-gnu-emacs@gnu.org; Fri, 01 Jan 2016 08:21:09 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aEzdg-0005V8-Kw for help-gnu-emacs@gnu.org; Fri, 01 Jan 2016 08:21:08 -0500 Original-Received: from plane.gmane.org ([80.91.229.3]:51015) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aEzdg-0005V2-ED for help-gnu-emacs@gnu.org; Fri, 01 Jan 2016 08:21:04 -0500 Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1aEzdd-0005dK-6Y for help-gnu-emacs@gnu.org; Fri, 01 Jan 2016 14:21:01 +0100 Original-Received: from nl106-137-56.student.uu.se ([130.243.137.56]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 01 Jan 2016 14:21:01 +0100 Original-Received: from embe8573 by nl106-137-56.student.uu.se with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 01 Jan 2016 14:21:01 +0100 X-Injected-Via-Gmane: http://gmane.org/ Mail-Followup-To: help-gnu-emacs@gnu.org Original-Lines: 39 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: nl106-137-56.student.uu.se Mail-Copies-To: never User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) Cancel-Lock: sha1:W2ZSikTCnhnmL11GpQwepilE5Go= 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:108563 Archived-At: Drew Adams writes: >> But other then time/space optimization, what would >> you say is the reason not to play it safe/sane and >> just return stuff, new stuff if necessary, but >> instead modify them directly? > > You will know it if you see it or when you really > need it! Morpheus: Unfortunately, no one can be *told* what the Matrix is. You have to see it for yourself. > If you don't see a need for sharing list structure > then playing it safe/sane is the right approach. Say that you do a rope-and-wheel mechanism to have a bathroom door close automatically. As a weight, you use a bottle. How do you tie the bottle to the rope? Do you just tie it as a kid would, with random loops all over, and then pull tight with your muscles? Or do you look up a professional knot in the BIG BOOK OF KNOTS? Just as using advanced Lisp to solve perhaps trivial, and definitely non-critical problems of Emacs configuration, it can be seen as hitting the heavy bag. If the real deal, whatever that is, ever appears, you'll be more ready than otherwise. If it doesn't appear, you at least have a good looking knot, some cool Elisp, and a fit body! -- underground experts united http://user.it.uu.se/~embe8573