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From: tomas@tuxteam.de
To: Heime <heimeborgia@protonmail.com>
Cc: help-gnu-emacs@gnu.org
Subject: Re: Check whether an object is an alist
Date: Tue, 17 Sep 2024 19:57:42 +0200	[thread overview]
Message-ID: <ZunDFiYI5t93y7+p@tuxteam.de> (raw)
In-Reply-To: <DgzzCeOZ2VHYlFg0WVSf8-R3I4_h7b3z_fEH1e0hysPmkupqe5bRjKdzCcI_2-TMZd8IzkDHGn86K-xjX_c6oWuiDNAUQTZK2ku45qjnHDA=@protonmail.com>

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On Tue, Sep 17, 2024 at 04:26:19PM +0000, Heime wrote:

[...]

> Is (null x) the part that allows nil, a non-pair object ?

Just ask Emacs:

  (cl-every (lambda (x)
              (or (null x)
                  (consp x)))
            '((foo . bar)
              nil
              (baz . quux)))
  
  => t
  
  (cl-every (lambda (x)
              (consp x))
            '((foo . bar)
              nil
              (baz . quux)))
  
  => nil

Now, should you decide you prefer the second variant, there is
a more concise way of writing it. This is left as an exercise
for the reader.

Cheers
-- 
t

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  reply	other threads:[~2024-09-17 17:57 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-09-16 10:29 Check whether an object is an alist Heime
2024-09-17  8:45 ` Heime
2024-09-17  9:38   ` Manuel Giraud via Users list for the GNU Emacs text editor
2024-09-17  9:46     ` tomas
2024-09-17 11:16       ` Heime
2024-09-17 11:23         ` tomas
2024-09-17 13:51           ` Heime
2024-09-17 13:58             ` tomas
2024-09-17 14:32               ` Heime
2024-09-17 15:20                 ` tomas
2024-09-17 16:26                   ` Heime
2024-09-17 17:57                     ` tomas [this message]
2024-09-17 18:04                       ` Heime
2024-09-17 18:28                         ` tomas
2024-09-17 19:20                           ` Heime
2024-09-17 19:35                             ` tomas
2024-09-17 21:02                               ` Heime
2024-09-17 21:25                                 ` Heime
2024-09-18  4:21                                   ` tomas
2024-09-18  4:52                                     ` Heime
2024-09-17 22:01                                 ` Stephen Berman
2024-09-17 19:22                 ` [External] : " Drew Adams

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