From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "Pascal J. Bourguignon" Newsgroups: gmane.emacs.help Subject: Re: `append' vs. `nconc' Date: Fri, 01 Jan 2016 07:25:21 +0100 Organization: Informatimago Message-ID: <87bn95ddf2.fsf@kuiper.lan.informatimago.com> References: <568164D8.6050700@ojkastl.de> <87io3iyr7t.fsf@debian.uxu> <87si2kezg1.fsf@mithlond.arda> <87a8osrlj4.fsf_-_@debian.uxu> <87lh8bgafa.fsf@mithlond.arda> <87io3fdqfm.fsf@mithlond.arda> 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 1451629822 32326 80.91.229.3 (1 Jan 2016 06:30:22 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 1 Jan 2016 06:30:22 +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 07:30:18 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 1aEtEA-0003uM-Cf for geh-help-gnu-emacs@m.gmane.org; Fri, 01 Jan 2016 07:30:18 +0100 Original-Received: from localhost ([::1]:57472 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aEtE9-0000r9-Ii for geh-help-gnu-emacs@m.gmane.org; Fri, 01 Jan 2016 01:30:17 -0500 Original-Path: usenet.stanford.edu!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail Original-Newsgroups: gnu.emacs.help Original-Lines: 35 Original-X-Trace: individual.net 2309hCAw7CP/8eOc0MU4Fw/nZUab8fe6j3viM46W5h16je5A0Q Cancel-Lock: sha1:NmFmYjc5Nzk3MTBiZjRhNmUwMmYwNzE2NjU0ZjUxM2JiOTJmODkyMg== sha1:50M87/WQh2B21/9W2lv2NIVnV1E= Face: iVBORw0KGgoAAAANSUhEUgAAADAAAAAwAQMAAABtzGvEAAAABlBMVEUAAAD///+l2Z/dAAAA oElEQVR4nK3OsRHCMAwF0O8YQufUNIQRGIAja9CxSA55AxZgFO4coMgYrEDDQZWPIlNAjwq9 033pbOBPtbXuB6PKNBn5gZkhGa86Z4x2wE67O+06WxGD/HCOGR0deY3f9Ijwwt7rNGNf6Oac l/GuZTF1wFGKiYYHKSFAkjIo1b6sCYS1sVmFhhhahKQssRjRT90ITWUk6vvK3RsPGs+M1RuR mV+hO/VvFAAAAABJRU5ErkJggg== X-Accept-Language: fr, es, en User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) Original-Xref: usenet.stanford.edu gnu.emacs.help:216272 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:108562 Archived-At: Emanuel Berg writes: > What is the reason one has to use `list'? (I suppose > the ` isn't safe, either.) list returns a fresh list. ` doesn't. ` may return a structure that shares literal substructures with others. Typically, it will be a tail, but it can also be some cars: `((a . b) (c . ,x) ,@y d e f) could translate to: (list* '(a . b) (cons 'c x) (append y '(d e f))) or something similar. Then each time you execute it, you get a list whose tail is the same literal (d e f), and whose car is the same literal cons (a . b). > And: In Pascal's examples he always used `setf'. > The help says it can be used for places as well as for > symbols. In the examples tho there has been only > symbols if I'm not mistaken. It's simplier to forget about set and setq, and always use setf. That frees two neurons to think about other things. -- __Pascal Bourguignon__ http://www.informatimago.com/ “The factory of the future will have only two employees, a man and a dog. The man will be there to feed the dog. The dog will be there to keep the man from touching the equipment.” -- Carl Bass CEO Autodesk