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

[Stefan Monnier]

> I assume it would be fairly easy to code such a macro (using `boundp'),
> but maybe it exists already?

AFAIK it doesn't exist yet.  The reason for it is that it is not
often useful.  Typically there are two cases:

- If the var exist, you want to set it and if not you have no fallback.
  In that case, it is typically harmless to set the var even when it
  doesn't exist, so the code just uses `setq` without bothering to test
  `boundp`.

- If the var exist you want to set it, and if it doesn't you 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.


-- Stefan