eachSubSet(subset, new P1<Set<A>>() {public void e(Set<A> subOfSub) {
//			System.out.println("set=" + set + ", subset=" + subset + ", subOfSub=" + subOfSub);
			// Not with a
			p1.e(subOfSub);
			
			// With a
			HashSet<A> newSub = new HashSet<A>(subOfSub);
			newSub.add(a);
			p1.e(newSub);
		}}