From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: David Kastrup Newsgroups: gmane.emacs.devel Subject: Re: Documentation for car and cdr Date: Thu, 26 Jan 2006 00:36:08 +0100 Message-ID: <85ek2vj2xj.fsf@lola.goethe.zz> References: <21088.1138231911@brains.moreideas.ca> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1138232194 17142 80.91.229.2 (25 Jan 2006 23:36:34 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Wed, 25 Jan 2006 23:36:34 +0000 (UTC) Cc: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu Jan 26 00:36:25 2006 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by ciao.gmane.org with esmtp (Exim 4.43) id 1F1uBT-0001SO-Rp for ged-emacs-devel@m.gmane.org; Thu, 26 Jan 2006 00:36:16 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1F1uEF-00044i-2C for ged-emacs-devel@m.gmane.org; Wed, 25 Jan 2006 18:39:07 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1F1uE3-00044X-SC for emacs-devel@gnu.org; Wed, 25 Jan 2006 18:38:55 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1F1uE2-000446-OL for emacs-devel@gnu.org; Wed, 25 Jan 2006 18:38:55 -0500 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1F1uE2-000443-Ei for emacs-devel@gnu.org; Wed, 25 Jan 2006 18:38:54 -0500 Original-Received: from [199.232.76.164] (helo=fencepost.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.52) id 1F1uBV-0007QH-KS for emacs-devel@gnu.org; Wed, 25 Jan 2006 18:36:17 -0500 Original-Received: from localhost ([127.0.0.1] helo=lola.goethe.zz) by fencepost.gnu.org with esmtp (Exim 4.34) id 1F1uB1-0005B6-O6; Wed, 25 Jan 2006 18:35:47 -0500 Original-Received: by lola.goethe.zz (Postfix, from userid 1002) id 3BAE81D3273B; Thu, 26 Jan 2006 00:36:09 +0100 (CET) Original-To: Peter Whaite In-Reply-To: <21088.1138231911@brains.moreideas.ca> (Peter Whaite's message of "Wed, 25 Jan 2006 18:31:51 -0500") User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.0.50 (gnu/linux) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:49549 Archived-At: Peter Whaite writes: > Kim F. Storm wrote: >> >> I fully agree, but notice that the doc strings for car and cdr >> say that the arg is "list". I think that part of the confusion >> is that a "pure" list does have a head and a tail and car==head >> and cdr==tail. > > Yes exactly right. As it is now the doc string gives the > misleading impression that c[ad]r operate on lists when they don't. The terminology in the Elisp manual distinguishes between "true lists", "circular lists" and "dotted lists". So a cons cell is a list always, though not necessarily a "true list". listp returns t whenever we have a cons cell or nil. -- David Kastrup, Kriemhildstr. 15, 44793 Bochum