@Override
        public Traversal<Vertex, Double> get_g_withSideEffectXx_100X_V_age_mathX__plus_xX() {
            return g.withSideEffect("x", 100).V().values("age").math("_ + x");
        }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/MathTest.java