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From: Emanuel Berg via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org>
To: help-gnu-emacs@gnu.org
Subject: Re: Is there a way of setting a variable only when it exists?
Date: Tue, 15 Mar 2022 07:50:43 +0100	[thread overview]
Message-ID: <877d8v4sl8.fsf@zoho.eu> (raw)
In-Reply-To: 87a6drviwp.fsf@mbork.pl

Marcin Borkowski wrote:

>>>   want to do something else. In that case, the something
>>>   else tends to depend on the specifics so (if (boundp
>>>   'foo) (setq foo ..) ...) is about s good as it gets.
>>
>> If it exists set it with `setq'. If it doesn't exist,
>> create and set it ... with `setq'?
>
> What if it's an internal Emacs variable which might become
> a user option one day (I submitted a bug report about it)
> and then my customization silently disappears? It's the
> "silently" part I want to guard against...

Yeah, that whole system ... *mumble*

But here you go,

(let ((var (variable-at-point t))) ; ANY-SYMBOL
  (when (and (custom-variable-p var)
             (get var 'custom-set) )
    (message "user variable") ))

-- 
underground experts united
https://dataswamp.org/~incal




  reply	other threads:[~2022-03-15  6:50 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
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 [this message]
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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