From: Andreas Politz <politza@fh-trier.de>
To: help-gnu-emacs@gnu.org
Subject: Re: How could I modify list element?
Date: Tue, 09 Dec 2008 17:36:21 +0100 [thread overview]
Message-ID: <1228840648.405357@arno.fh-trier.de> (raw)
In-Reply-To: <mailman.2319.1228836378.26697.help-gnu-emacs@gnu.org>
richardeng wrote:
> Hi all,
> setcar/setcdr is not convenient.
> In a long list, ex.
> (setq a '(a b c d e f g))
> I want to change 'e to 'E.
> I need a function: (set-list-elt list old-elt new-elt)
>
> How? translate list to vector, modify, then turn it back???
>
>
Why don't you ...
(let ((list '(a b c d e)))
(or
(and (require 'cl nil t)
(substitute 'E 'e list))
(mapcar #'(lambda (elt)
(if (eq elt 'e) 'E elt))
list)))
-ap
next parent reply other threads:[~2008-12-09 16:36 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <mailman.2319.1228836378.26697.help-gnu-emacs@gnu.org>
2008-12-09 16:36 ` Andreas Politz [this message]
2008-12-09 20:46 ` How could I modify list element? Niels Giesen
2008-12-09 14:15 richardeng
2008-12-09 15:37 ` Alan Mackenzie
2008-12-09 17:43 ` richardeng
[not found] ` <mailman.2345.1228845668.26697.help-gnu-emacs@gnu.org>
2008-12-09 20:30 ` Andreas Politz
2008-12-09 17:21 ` Thierry Volpiatto
2008-12-09 17:26 ` Thierry Volpiatto
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