indexing description: "A list item with a topic object." author: "Vincent Brendel" class TOPIC_LIST_ITEM inherit EV_LIST_ITEM rename data as topic redefine topic end creation make_item feature -- Initialization make_item(li: EV_LIST; top: E_TOPIC) is -- Initialize with parent 'li'. require not_void: li /= Void and then top /= Void and then top.id/=Void do make_with_text(li, top.id) topic := top end feature -- Access topic: E_TOPIC -- The topic object. invariant TOPIC_LIST_ITEM_topic_exists: topic /= Void end -- class TOPIC_LIST_ITEM