code: public static LongStreamEx of(LongStream stream) {
          return stream instanceof LongStreamEx ? (LongStreamEx) stream
                  : new LongStreamEx(stream, StreamContext.of(stream));
      }
docs: Returns a {@code LongStreamEx} object which wraps given
  {@link LongStream}.
  
  <p>
  The supplied stream must not be consumed or closed when this method is
  called. No operation must be performed on the supplied stream after it's
  wrapped.
  
  @param stream original stream
  @return the wrapped stream
  @since 0.0.8