@Override
    public int hashCode() {
        int result = super.hashCode();
        return Objects.hash(result, valueTraversal, parameterItems);
    }
A map step that returns the difference of the traverser and the provided arguments without duplicates.
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/DifferenceStep.java