bug#24229: 25.1; Can't set EPA program

[Eli Zaretskii]

> From: Daiki Ueno <ueno@gnu.org>
> Date: Wed, 17 Aug 2016 09:46:01 +0200
> Cc: "24229@debbugs.gnu.org" <24229@debbugs.gnu.org>
> 
> > None of these variables forces the use of customize. Why 
> > is epg-gpg-program such a special case?
> 
> That is primarily because of the UX differences between three maintained
> versions of GnuPG: 2.0, 2.1, and 1.x.  GnuPG 2.0 does not provide a way
> to prompt passphrase without GUI, but others do.  Some people are fine
> with 2.0 as they use Emacs on a graphical environment only, but other
> people are not.
> 
> So, we really need to take account of user's intention here; check
> whether the variable set by user or it is the default value.  With
> 'setq' it is not possible to have such distinction.

Doesn't Customize provide some functions that allow such a
distinction?  The Customize UI surely is able to tell when a variable
was "changed not through Customize", isn't that what you want?

Thanks.