We had one more question like that today:
http://emacs.stackexchange.com/q/17256/115


--
Kaushal Modi

On Thu, Oct 8, 2015 at 12:21 PM, John Wiegley <johnw@newartisans.com> wrote:

> >>>>> Artur Malabarba <bruce.connor.am@gmail.com> writes:
>
> > Actually, we have that already.
> > It's a defcustom called custom-theme-directory. It only holds one
> directory,
> > and it is safe to be customised by the user.
>
> In that case, changing the other defcustom to defvar sounds like the right
> change.
>
> John
>
>