Re: Is there a way of setting a variable only when it exists?

[Marcin Borkowski]

On 2022-03-16, at 01:47, Michael Heerdegen <michael_heerdegen@web.de> wrote:

> Marcin Borkowski <mbork@mbork.pl> writes:
>
>> 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?
>
> That normally does not happen.  `defcustom' doesn't alter existing
> bindings.  You can still `setq' a user option.  There is no problem
> unless the "meaning" of the variable values changed in an backward
> incompatible way.  I guess nothing can protect against that.
>
> The only notable case I can think of is when things change so that
> setting the variable doesn't have the expected effect any more because
> the custom setter has gotten additional side effects (more than only
> setting the value).  Is that your concern?

No, my concern is the variable changing its _name_.

-- 
Marcin Borkowski
http://mbork.pl