public Object evaluate(Context c, HashMap map, DataFactory factory) {
		IVPNumber expressionA = (IVPNumber) ((DataObject)map.get(expA)).evaluate(c, map, factory);
		IVPNumber expressionB = (IVPNumber) ((DataObject)map.get(expB)).evaluate(c, map, factory);
		return expressionA.greaterThan(expressionB, c, map, factory);
	}