From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Andreas Schwab Newsgroups: gmane.emacs.devel Subject: Re: Using empty_string as the only "" string Date: Wed, 25 Apr 2007 00:35:35 +0200 Message-ID: References: <462E310C.20400@yandex.ru> <85k5w1cu64.fsf@lola.goethe.zz> <462E7FB5.7090905@gmail.com> <857is1csoy.fsf@lola.goethe.zz> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable X-Trace: sea.gmane.org 1177454149 29597 80.91.229.12 (24 Apr 2007 22:35:49 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Tue, 24 Apr 2007 22:35:49 +0000 (UTC) Cc: Juanma Barranquero , Dmitry Antipov , "Lennart Borgman \(gmail\)" , emacs-devel@gnu.org To: David Kastrup Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Apr 25 00:35:46 2007 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1HgTbt-0005lp-Mz for ged-emacs-devel@m.gmane.org; Wed, 25 Apr 2007 00:35:45 +0200 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HgThR-0006ML-Rh for ged-emacs-devel@m.gmane.org; Tue, 24 Apr 2007 18:41:29 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1HgThO-0006ME-9g for emacs-devel@gnu.org; Tue, 24 Apr 2007 18:41:26 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1HgThL-0006M2-Tk for emacs-devel@gnu.org; Tue, 24 Apr 2007 18:41:24 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HgThL-0006Lz-O9 for emacs-devel@gnu.org; Tue, 24 Apr 2007 18:41:23 -0400 Original-Received: from ns2.suse.de ([195.135.220.15] helo=mx2.suse.de) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1HgTbl-0004Go-J4; Tue, 24 Apr 2007 18:35:37 -0400 Original-Received: from Relay2.suse.de (mail2.suse.de [195.135.221.8]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx2.suse.de (Postfix) with ESMTP id DF9712162C; Wed, 25 Apr 2007 00:35:35 +0200 (CEST) X-Yow: Join the PLUMBER'S UNION!! In-Reply-To: <857is1csoy.fsf@lola.goethe.zz> (David Kastrup's message of "Wed, 25 Apr 2007 00:29:17 +0200") User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/22.0.97 (gnu/linux) X-detected-kernel: Linux 2.4-2.6 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:70009 Archived-At: David Kastrup writes: > Aren't grounded at all. (concat "a" "b") does not make "b" part of > the result. So (concat "a" "") and (concat "b" "") would not share > the same "" even if one replaced both of them by the same object. > > Every created string is a separate object not containing any other > string as a part. The same is not true for lists. You can, for > example, modify a sublist and in the process change the list > containing it. > > This does not happen for substrings. Since you can't modify the empty string there is no contradiction. Andreas. --=20 Andreas Schwab, SuSE Labs, schwab@suse.de SuSE Linux Products GmbH, Maxfeldstra=DFe 5, 90409 N=FCrnberg, Germany PGP key fingerprint =3D 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED= 5 "And now for something completely different."