docs: @SuppressWarnings("unchecked")
      public final static <T> Tuple4<Stream<T>, Stream<T>, Stream<T>, Stream<T>> quadruplicate(final Stream<T> stream) {
          final Stream<Stream<T>> its = Streams.toBufferingCopier(stream.iterator(), 4)
                                                   .stream()
                                                   .map(it -> Streams.stream(it));
          final Iterator<Stream<T>> it = its.iterator();
          return new Tuple4(
                            it.next(), it.next(), it.next(), it.next());
      }