Hello,

There are several programming languages with support for D-Bus client
implementation.  For example, with the following code:
https://git.gnome.org/browse/gnome-shell/tree/js/ui/keyboard.js#n56

  const CaribouDaemonIface = '<node> \
  <interface name="org.gnome.Caribou.Daemon"> \
  <method name="Run" /> \
  <method name="Quit" /> \
  </interface> \
  </node>';

  const CaribouDaemonProxy = Gio.DBusProxy.makeProxyWrapper(CaribouDaemonIface);

One can call a D-Bus method as a normal method of CaribouDaemonProxy.
This is really handy and I wished to have similar feature in Elisp
(though I haven't ever written any practical D-Bus code in Elisp).

Thanks to cl-generic, I gave it a try.  With the attached code (far from
complete though), a client can be implemented as:

  (dbus-define-proxy search-provider "\
  <node>
    <interface name=\"org.gnome.Shell.SearchProvider2\">
      <method name=\"GetInitialResultSet\">
        <arg type=\"as\" name=\"terms\" direction=\"in\" />
        <arg type=\"as\" name=\"results\" direction=\"out\" />
      </method>
      <!-- actually, there are more methods in this interface -->
    </interface>
  </node>")

Then you can create a client and call D-Bus methods:

  (setq search-provider
        (search-provider-make :session
                              "org.gnome.Weather.BackgroundService"
                              "/org/gnome/Weather/BackgroundService"))
  (search-provider-call-GetInitialResultSet search-provider '("tokyo"))

If this seems to be useful, I can finish it off as a patch.

Thanks,
--
Daiki Ueno