public final boolean doEmit(final Traverser.Admin<S> traverser, boolean emitFirst) {
        return emitFirst == this.emitFirst && null != this.emitTraversal && TraversalUtil.test(traverser, this.emitTraversal);
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/branch/RepeatStep.java