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

[Daiki Ueno]

Nick Helm <nick@tenpoint.co.nz> writes:

> 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.

Regards,
-- 
Daiki Ueno