ng a class also updates the
configuration of all subclasses of the class and all objects that are
instances of that class or which mix it in (as modified by any per-instance
configuration). The way in which the configuration is done is controlled by
either the <I>defScript</I> argument or by the <I>subcommand</I> and following
<I>arg</I> arguments; when the second is present, it is exactly as if all the
arguments from <I>subcommand</I> onwards are made into a list and that list is
used as the <I>defScript</