docs: public <U> FutureStream<U> fromIterable(final Iterable<U> iter) {
          if(iter instanceof FutureStream){
              return (FutureStream<U>)iter;
          }
          final ReactiveSeq<U> seq = iter instanceof List ? ReactiveSeq.fromList((List) iter) : ReactiveSeq.fromIterable(iter);
          return this.fromStream(seq);
      }