public static <S> Iterable<S> peek(final Iterable<S> iterable, final Consumer<S> function) {
        return () -> IteratorUtils.peek(iterable.iterator(), function);
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/util/iterator/IteratorUtils.java