docs: public <U> FutureStream<U> fromIteratorAsync(final Iterator<? extends Supplier<U>> actions) {
  
          return this.<U> constructFutures(StreamSupport.<Supplier<U>> stream(Spliterators.<Supplier<U>> spliteratorUnknownSize(actions,
                                                                                                                                Spliterator.ORDERED),
                                                                              false)
                                                        .map(next -> CompletableFuture.supplyAsync(next, getExecutor())));
      }