    deferred class
    	SUBSET_STRATEGY [G]

    General
    	cluster: base
    	description:
    		"Strategies for computing several features of subsets. The computing
    		strategy is optimized depending on the type of elements contained in
    		the set."

    Ancestors
    	ANY

    Queries
    	disjoint (set1, set2: TRAVERSABLE_SUBSET [G]): BOOLEAN

    Commands
    	symdif (set1, set2: TRAVERSABLE_SUBSET [G])