From xemacs-m  Wed Apr 23 21:22:42 1997
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Date: Wed, 23 Apr 1997 19:22:04 -0700
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From: Martin Buchholz <mrb@Eng.Sun.COM>
To: Steven L Baur <steve@miranova.com>
Cc: xemacs-beta@xemacs.org
Subject: Re: `purecopy' with lists
In-Reply-To: <m2wwptjhvs.fsf@altair.xemacs.org>
References: <kig67xdyioj.fsf@jagor.srce.hr>
	<m2wwptjhvs.fsf@altair.xemacs.org>
X-Mailer: VM 6.24 under 20.1 XEmacs Lucid (beta15)
Reply-To: Martin Buchholz <mrb@Eng.Sun.COM>

>>>>> "sb" == Steven L Baur <steve@miranova.com> writes:

sb> Hmm, so why can you do:

sb> (setf (car completion-ignored-extensions) ".O")

(setf (aref (car completion-ignored-extensions) 1) ?x)

=> Attempt to modify read-only object

The string is not modifyable, but the pointer to it in the cons cell is.

Martin

