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From: Philipp Stephani <p.stephani2@gmail.com>
To: Glenn Morris <rgm@gnu.org>
Cc: 25166@debbugs.gnu.org
Subject: bug#25166: 26.0.50; It shouldn't be possible to set the function cell of nil and t
Date: Mon, 26 Dec 2016 19:29:17 +0000	[thread overview]
Message-ID: <CAArVCkS990mMYOQMks5qA9TX_cV2UfoyJ2KXeLxLi+dZZsOsyA@mail.gmail.com> (raw)
In-Reply-To: <1hpokwx5br.fsf@fencepost.gnu.org>

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Glenn Morris <rgm@gnu.org> schrieb am Mo., 12. Dez. 2016 um 21:25 Uhr:

> Glenn Morris wrote:
>
> > Philipp wrote:
> >
> >> You can set the function cell of nil and t using `fset' and friends.
> >> But you can't call the `nil' function using (nil) (it does work with
> >> (t)).  I think that attempting to set the function cell of nil and t is
> >> almost always a bug -- probably the programmer wanted to set a real
> >> symbol, but some of the constants got passed.  I propose to signal an
> >> error (e.g. `setting-constant') whenever the function cell of nil and t
> >> is modified; maybe the same should happen for keywords.
> >
> > I just did this yesterday...
> > See https://debbugs.gnu.org/25110, ba8e883, and 3fd4433.
>
> And now see also ffb1302. :)
> Anyway, I only did "nil", since as you say "t" can actually be called as
> a function. But you are right that it's probably unintended.
>
>
Thanks! Interestingly the behavior was already added in 1994 (commit
c15c5d408d696928862ca2848a359231e373556c), but apparently reverted later.
I'd suggest to simply reinstate that commit.

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  reply	other threads:[~2016-12-26 19:29 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-12-11  9:41 bug#25166: 26.0.50; It shouldn't be possible to set the function cell of nil and t Philipp
2016-12-11 18:38 ` Glenn Morris
2016-12-12 20:25   ` Glenn Morris
2016-12-26 19:29     ` Philipp Stephani [this message]
2016-12-26 19:41       ` Philipp Stephani
2016-12-26 19:47       ` Eli Zaretskii
2016-12-27 15:15         ` Stefan Monnier
2016-12-27 22:49           ` Eli Zaretskii
2016-12-27 23:11             ` Stefan Monnier
2017-05-01 14:44               ` Philipp Stephani
2017-05-01 15:12                 ` Eli Zaretskii
2017-10-27 17:59                   ` Noam Postavsky
2017-10-28 16:16                     ` Stefan Monnier
2017-10-28 16:45                       ` Noam Postavsky
2017-10-29 18:10                         ` Stefan Monnier

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