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From: Tassilo Horn <tassilo@member.fsf.org>
To: help-gnu-emacs@gnu.org
Subject: Re: elisp - anonymous function in an association list?
Date: Thu, 29 Nov 2007 16:41:36 +0100	[thread overview]
Message-ID: <87ir3lrrdb.fsf@member.fsf.org> (raw)
In-Reply-To: 10f246a9-2a9b-477e-806d-7e3b38ce2607@i29g2000prf.googlegroups.com

apatheticagnostic <apatheticagnostic@gmail.com> writes:

Hi,

> Both calls fail, with an error message like so:
>
> for "b": Debugger entered--Lisp error: (invalid-function ((function
> (lambda nil (message "B worked too!")))))
>
> for "a": Debugger entered--Lisp error: (invalid-function ((quote
> (lambda nil (message "We worked!")))))

This works:

--8<---------------cut here---------------start------------->8---
(defvar sample-alist '(("a" (lambda ()
                              (message "We worked!")))
                       ("b" (lambda ()
                              (message "B worked too!")))))

(defun test-call (x)
  (funcall (cadr (assoc x sample-alist))))

(test-call "a")
(test-call "b")
--8<---------------cut here---------------end--------------->8---

First, you don't need to quote the lambdas inside the list, which is
already quoted.  Second in `test-call' you don't want the cdr but the
car of the cdr (= cadr) from the assoc.

Bye,
Tassilo

      parent reply	other threads:[~2007-11-29 15:41 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-11-29 14:00 elisp - anonymous function in an association list? apatheticagnostic
2007-11-29 14:50 ` Marc Tfardy
2007-11-29 15:01   ` apatheticagnostic
2007-11-29 15:04     ` apatheticagnostic
2007-11-30  0:08       ` Johan Bockgård
2007-11-29 15:32     ` David Kastrup
2007-11-29 15:52       ` apatheticagnostic
2007-11-29 21:24       ` Barry Margolin
2007-11-29 15:41 ` Tassilo Horn [this message]

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