From: Michael Heerdegen <michael_heerdegen@web.de>
To: Drew Adams <drew.adams@oracle.com>
Cc: Eric Abrahamsen <eric@ericabrahamsen.net>, 34708@debbugs.gnu.org
Subject: bug#34708: alist-get has unclear documentation
Date: Tue, 12 Mar 2019 14:12:31 +0100 [thread overview]
Message-ID: <87a7i01bk0.fsf@web.de> (raw)
In-Reply-To: <3af3b645-84e0-4208-be48-810e8cd2cfa8@default> (Drew Adams's message of "Mon, 11 Mar 2019 07:52:31 -0700 (PDT)")
Drew Adams <drew.adams@oracle.com> writes:
> > (progn
> > (setq my-alist '((a . 1) (b . 2)))
> > (push (car my-alist) my-alist)
> > ;; my-alist ==> (#1=(a . 1) #1# (b . 2))
> > (setf (alist-get 'a my-alist nil 'remove) nil))
> > ;; my-alist ==> ((b . 2))
> >
> > This is because the code uses delq to delete a found cons, and delq
> > removes all `eq' elements.
> >
> > Is it worth to document or change that?
>
> Sounds like an implementation/design artifact. If that will stay as
> part of the design then yes, I'd say such behavior needs to be
> documented.
BTW with a different viewpoint, when you use
(setcdr (assoc 'a my-alist) 17)
on the above degenerated alist you also change _both_ of the 'a
associations, so one could argue that the `alist-get' setter behaves
correctly when removing both: there are not two 'a associations in
MY-ALIST but the same one has just been added two times, so it's correct
to remove both of them.
Michael.
next prev parent reply other threads:[~2019-03-12 13:12 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-02 4:50 bug#34708: alist-get has unclear documentation Miguel V. S. Frasson
2019-03-02 9:25 ` Michael Heerdegen
2019-03-02 15:40 ` Miguel V. S. Frasson
2019-03-02 18:10 ` Michael Heerdegen
2019-03-02 19:06 ` Eric Abrahamsen
2019-03-03 0:15 ` Phil Sainty
2019-03-03 12:50 ` Michael Heerdegen
2019-03-19 1:35 ` Michael Heerdegen
2019-03-02 19:51 ` Miguel V. S. Frasson
2019-03-02 20:32 ` Eric Abrahamsen
2019-03-03 11:32 ` Miguel V. S. Frasson
2019-03-03 12:21 ` Michael Heerdegen
2019-03-03 15:51 ` Drew Adams
2019-03-03 16:49 ` Eric Abrahamsen
2019-03-04 16:24 ` Eric Abrahamsen
2019-03-04 16:38 ` Michael Heerdegen
2019-03-04 17:16 ` Eric Abrahamsen
2019-03-04 18:22 ` Michael Heerdegen
2019-03-04 22:49 ` Eric Abrahamsen
2019-03-05 12:35 ` Michael Heerdegen
2019-03-05 22:50 ` Eric Abrahamsen
2019-03-06 0:16 ` Drew Adams
2019-03-11 13:39 ` Michael Heerdegen
2019-03-11 14:52 ` Drew Adams
2019-03-11 16:19 ` Michael Heerdegen
2019-03-11 17:48 ` Drew Adams
2019-03-12 13:04 ` Michael Heerdegen
2019-03-12 14:48 ` Drew Adams
2019-03-12 16:08 ` Michael Heerdegen
2019-03-12 16:48 ` Drew Adams
2019-03-12 17:45 ` Michael Heerdegen
2019-03-12 13:12 ` Michael Heerdegen [this message]
2019-03-12 14:53 ` Drew Adams
2019-03-12 15:38 ` Michael Heerdegen
2019-03-12 16:18 ` Drew Adams
2019-03-12 17:55 ` Michael Heerdegen
2019-03-15 15:54 ` Michael Heerdegen
2019-03-15 18:48 ` Eric Abrahamsen
2019-03-27 22:31 ` Michael Heerdegen
2019-04-19 1:33 ` Michael Heerdegen
2019-04-19 2:24 ` bug#34708: Thanks Miguel V. S. Frasson
2019-04-19 4:18 ` Michael Heerdegen
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