    deferred class
    	SED_OBJECT_GRAPH_TRAVERSABLE

    General
    	cluster: base
    	description: "Objects that traverse object graphs starting at the root object."

    Ancestors
    	ANY

    Queries
    	is_object_action_set: BOOLEAN
    	is_root_object_set: BOOLEAN
    	object_action: PROCEDURE [ANY, TUPLE [ANY]]
    	root_object: ANY
    	visited_objects: ARRAYED_LIST [ANY]

    Commands
    	set_object_action (an_object_action: [like object_action] PROCEDURE [ANY, TUPLE [ANY]])
    	set_root_object (an_object: [like root_object] ANY)
    	traverse
    	wipe_out