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From: Eli Zaretskii <eliz@gnu.org>
To: help-gnu-emacs@gnu.org
Subject: Re: Which Elisp types are mutable?
Date: Mon, 05 Jul 2021 21:48:51 +0300	[thread overview]
Message-ID: <834kd8ha0c.fsf@gnu.org> (raw)
In-Reply-To: <4AA1E624-B979-4B08-8AE0-E33A1C9A0E94@gmail.com> (message from Philipp on Mon, 5 Jul 2021 20:41:58 +0200)

> From: Philipp <p.stephani2@gmail.com>
> Date: Mon, 5 Jul 2021 20:41:58 +0200
> Cc: Help Gnu Emacs mailing list <help-gnu-emacs@gnu.org>
> 
> > Well, in my book, "you can't mutate them" is.  You always /can/ mutate
> > a string, but of you do it in certain circumstances, you're asking for
> > trouble.
> 
> You can mutate all objects, because all of them are stored in mutable memory.

Not if you put it in read-only memory: you'd get a segfault with any
modern OS.

> For a reference manual, "you're asking for trouble" isn't a terribly useful statement.

And "you must not mutate them" is?  At least "you're asking for
trouble" explains why not, especially if it actually describes some of
the trouble.



  reply	other threads:[~2021-07-05 18:48 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-03  4:03 Which Elisp types are mutable? Marcin Borkowski
2021-06-03 12:11 ` Philipp
2021-06-05 11:22   ` Marcin Borkowski
2021-06-05 12:58     ` Philipp
2021-06-05 14:25       ` Stefan Monnier via Users list for the GNU Emacs text editor
2021-07-05 18:40         ` Philipp
2021-07-05 20:19           ` Stefan Monnier
2021-07-05 20:44             ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-07-05 20:58               ` Stefan Monnier via Users list for the GNU Emacs text editor
2021-07-05 21:03                 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-06-05 19:19       ` Marcin Borkowski
2021-06-05 20:17         ` [External] : " Drew Adams
2021-06-05 20:36           ` Dmitry Gutov
2021-06-06  1:57             ` Drew Adams
2021-07-05 18:41         ` Philipp
2021-07-05 18:48           ` Eli Zaretskii [this message]
2021-07-05 18:55             ` tomas
2021-07-05 19:26               ` [External] : " Drew Adams
2021-07-05 19:40                 ` tomas
2021-07-05 20:03                   ` Drew Adams
2021-07-05 20:12                     ` tomas
2021-07-05 20:39                       ` Drew Adams
2021-07-05 20:58                         ` Emanuel Berg via Users list for the GNU Emacs text editor

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