Re: [PATCH] Make display-time-mode time zone configurable

[Mark Oteiza <mvoteiza@udel.edu>]

On 15/02/16 at 08:45pm, Paul Eggert wrote:
> Mark Oteiza wrote:
> > +(defcustom display-time-zone nil
> > +  "Variable specifying the time zone used in `display-time-string-forms'.
> > +See the function `format-time-string' for an explanation of
> > +its ZONE variable."
> > +  :type '(choice (const :tag "Emacs Local Time" nil)
> > +                 (const :tag "Universal Time" t)
> > +                 (const :tag "System Wall Clock Time" wall)
> > +                 (string "Time Zone Rule"))
> > +  :link '(function-link format-time-string)
> > +  :group 'display-time)
> 
> This new defcustom seems to duplicate some or all of the existing defcustom
> time-stamp-time-zone. Should there be just custom var? or if there should be
> two, how should they differ in operation?

I suppose ideally there would just be one; however, it appears to me
that lots of time-related things are fragmented across Emacs.  For
instance, setting 24hr clock in display-time has its own defcustom, but
to do the same for things that use calendarfu involves setting
calendar-time-display-form.

This patch just conveniently exposes the ZONE feature in
display-time-mode in the same way time-stamp-time-zone does in
time-stamp.el.  Would it make sense to put a defcustom in (I guess)
time.el and have time-stamp.el use it?