From: Eli Zaretskii <eliz@gnu.org>
To: help-gnu-emacs@gnu.org
Subject: Re: Is there a way of setting a variable only when it exists?
Date: Mon, 14 Mar 2022 14:52:02 +0200 [thread overview]
Message-ID: <83zglsk87h.fsf@gnu.org> (raw)
In-Reply-To: <87lexdul8e.fsf@mbork.pl> (message from Marcin Borkowski on Mon, 14 Mar 2022 07:00:33 +0100)
> From: Marcin Borkowski <mbork@mbork.pl>
> Date: Mon, 14 Mar 2022 07:00:33 +0100
>
> I'd like to be able to say something like
>
> (setq-safe hello "world")
>
> so that `hello' is set to `"world"' if it is an existing variable (e.g.,
> defined by `defvar') and an error is raised if `hello' does not exist.
>
> Rationale: I'm setting an internal Emacs variable. At the same time,
> I submitted a feature request to turn it into a user option, so that
> it's possible that in a future version of Emacs it's going to change its
> name (it has two dashes in it). I want to be warned then that I need to
> change my `init.el' accordingly.
>
> I assume it would be fairly easy to code such a macro (using `boundp'),
> but maybe it exists already?
Why not just use boundp?
next prev parent reply other threads:[~2022-03-14 12:52 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-14 6:00 Is there a way of setting a variable only when it exists? Marcin Borkowski
2022-03-14 12:52 ` Eli Zaretskii [this message]
2022-03-14 13:16 ` Stefan Monnier via Users list for the GNU Emacs text editor
2022-03-14 13:48 ` Emanuel Berg via Users list for the GNU Emacs text editor
2022-03-15 6:17 ` Marcin Borkowski
2022-03-15 6:50 ` Emanuel Berg via Users list for the GNU Emacs text editor
2022-03-15 6:58 ` Jean Louis
2022-03-15 7:45 ` Marcin Borkowski
2022-03-15 8:12 ` Jean Louis
2022-03-15 7:49 ` tomas
2022-03-15 8:13 ` Jean Louis
2022-03-15 8:36 ` tomas
2022-03-15 9:28 ` Jean Louis
2022-03-15 10:01 ` tomas
2022-03-15 11:29 ` Emanuel Berg via Users list for the GNU Emacs text editor
2022-03-15 8:14 ` Emanuel Berg via Users list for the GNU Emacs text editor
2022-03-15 15:33 ` [External] : " Drew Adams
2022-03-15 15:38 ` Drew Adams
2022-03-16 18:32 ` Marcin Borkowski
2022-03-16 0:47 ` Michael Heerdegen
2022-03-16 18:33 ` Marcin Borkowski
2022-03-16 6:02 ` Tomas Nordin
2022-03-16 6:37 ` Emanuel Berg via Users list for the GNU Emacs text editor
2022-03-16 18:34 ` Marcin Borkowski
2022-03-15 6:48 ` Jean Louis
2022-03-14 22:09 ` Michael Heerdegen
2022-03-15 6:16 ` Marcin Borkowski
2022-03-15 7:05 ` Emanuel Berg via Users list for the GNU Emacs text editor
2022-03-16 0:25 ` Michael Heerdegen
2022-03-16 18:33 ` Marcin Borkowski
2022-03-16 19:25 ` Michael Heerdegen
2022-03-18 5:58 ` Marcin Borkowski
2022-03-16 20:35 ` Emanuel Berg via Users list for the GNU Emacs text editor
2022-03-17 20:47 ` Stefan Monnier via Users list for the GNU Emacs text editor
2022-03-18 5:59 ` Marcin Borkowski
2022-03-18 17:59 ` Jean Louis
2022-03-19 9:25 ` Emanuel Berg via Users list for the GNU Emacs text editor
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