From: "T.V Raman" <raman@google.com>
To: emacs-devel@gnu.org
Subject: lists, plain conses and length
Date: Thu, 3 Sep 2020 19:23:34 -0700 (PDT) [thread overview]
Message-ID: <20200904022334.791EBC2177B@raman-glaptop.localdomain> (raw)
Ran into this while trying to distinguish a cons from a list:
Try this:
(setq a (cons 1 2)) => (1 . 2)
(consp a) => t
(listp a) => t
(length a)=> Debugger entered--Lisp error: (wrong-type-argument listp 2)
Q: how does one distinguish a cons from a list.
The error message for length may need fixing since it says the
argument passed to it is not a list (it's correct) but then listp is wrong?
--
♉ Id: kg:/m/0285kf1 🦮
--
♉ Id: kg:/m/0285kf1 🦮
--
♉ Id: kg:/m/0285kf1 🦮
next reply other threads:[~2020-09-04 2:23 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-04 2:23 T.V Raman [this message]
2020-09-04 2:26 ` lists, plain conses and length Stefan Monnier
2020-09-04 14:19 ` T.V Raman
2020-09-04 2:29 ` Lars Ingebrigtsen
2020-09-04 8:53 ` tomas
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