SYNOPSIS
        object *deep_inventory(void)
        object *deep_inventory(object ob)

DESCRIPTION
        Returns an array of the objects contained in the inventory of
        ob (or this_object() if no arg given) and in the inventories
        of these objects, climbing down recursively.

        ob
           ob1
           ob2
              ob21  deep_inventory(ob) => ({ob1, ob2, ob3, ob4, ob21, ob31})
           ob3
              ob31
           ob4

SEE ALSO
        first_inventory(E), next_inventory(E), all_inventory(E)