@CanIgnoreReturnValue
    public Builder addAll(LongStream stream) {
      Spliterator.OfLong spliterator = stream.spliterator();
      long size = spliterator.getExactSizeIfKnown();
      if (size > 0) { // known *and* nonempty
        ensureRoomFor(Ints.saturatedCast(size));
      }
      spliterator.forEachRemaining((LongConsumer) this::add);
      return this;
    }

     */
    @CanIgnoreReturnValue
    public Builder addAll(IntStream stream) {
      Spliterator.OfInt spliterator = stream.spliterator();
      long size = spliterator.getExactSizeIfKnown();
      if (size > 0) { // known *and* nonempty
        ensureRoomFor(Ints.saturatedCast(size));
      }
      spliterator.forEachRemaining((IntConsumer) this::add);
      return this;
    }