From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Chong Yidong Newsgroups: gmane.emacs.devel Subject: Re: Why isn't the string returned by symbol-name read-only? Date: Sat, 23 Jan 2010 16:53:57 -0500 Message-ID: <87vdespjwq.fsf@stupidchicken.com> References: <4B5B6250.1080108@censorshipresearch.org> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1264283662 12029 80.91.229.12 (23 Jan 2010 21:54:22 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 23 Jan 2010 21:54:22 +0000 (UTC) Cc: Emacs development discussions To: Daniel Colascione Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Jan 23 22:54:13 2010 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 1NYnvp-0000hk-9v for ged-emacs-devel@m.gmane.org; Sat, 23 Jan 2010 22:54:13 +0100 Original-Received: from localhost ([127.0.0.1]:55887 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NYnvq-0002eA-Hv for ged-emacs-devel@m.gmane.org; Sat, 23 Jan 2010 16:54:14 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NYnvk-0002dC-K3 for emacs-devel@gnu.org; Sat, 23 Jan 2010 16:54:08 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NYnvg-0002YP-GQ for emacs-devel@gnu.org; Sat, 23 Jan 2010 16:54:08 -0500 Original-Received: from [199.232.76.173] (port=54750 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NYnvg-0002YE-Cq for emacs-devel@gnu.org; Sat, 23 Jan 2010 16:54:04 -0500 Original-Received: from pantheon-po33.its.yale.edu ([130.132.50.94]:59174) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1NYnvf-000833-UQ for emacs-devel@gnu.org; Sat, 23 Jan 2010 16:54:04 -0500 Original-Received: from furry ([192.54.222.11]) (authenticated bits=0) by pantheon-po33.its.yale.edu (8.12.11.20060308/8.12.11) with ESMTP id o0NLrwrK013198 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Sat, 23 Jan 2010 16:53:58 -0500 Original-Received: by furry (Postfix, from userid 1000) id 0116EC05D; Sat, 23 Jan 2010 14:53:57 -0700 (MST) In-Reply-To: <4B5B6250.1080108@censorshipresearch.org> (Daniel Colascione's message of "Sat, 23 Jan 2010 15:55:44 -0500") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1.91 (gnu/linux) X-YaleITSMailFilter: Version 1.2c (attachment(s) not renamed) X-detected-operating-system: by monty-python.gnu.org: GNU/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:120313 Archived-At: Daniel Colascione writes: > Consider > > (let ((name (symbol-name 'foo))) > (aset name 0 ?x) > (cons name (symbol-name 'foo))) > > That yields ("xoo" . " xoo") > > Now try > > > (let ((name (symbol-name 'car))) > (aset name 0 ?x) > (cons name (symbol-name 'car))) > > That returns in an error when you try to evaluate it. The object > returned by (symbol-name 'car) must have some read-only bit set. > > Why isn't that bit set for *all* symbol names? Users will always have enough rope to hang themselves. I don't think we need to lose sleep over this, unless this is demonstrated to be a problem in the real world.