@Test
    @LoadGraphWith(MODERN)
    public void g_withSackX0X_V_outE_sackXsumX_byXweightX_inV_sack_sum() {
        final Traversal<Vertex, Double> traversal = get_g_withSackX0X_V_outE_sackXsumX_byXweightX_inV_sack_sum();
        printTraversalForm(traversal);
        assertEquals(3.5d, traversal.next(), 0.00001d);
        assertFalse(traversal.hasNext());
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/sideEffect/SackTest.java