code: func ReaderIteratorNoHeader(in DataInput, format PackedFormat, version,
  	valueCount, bitsPerValue, mem int) ReaderIterator {
  	CheckVersion(int32(version))
  	return newPackedReaderIterator(format, version, valueCount, bitsPerValue, in, mem)
  }
docs: /*
  Expert: Restore a ReaderIterator from a stream without reading metadata at the
  beginning of the stream. This method is useful to restore data from streams
  which have been created using WriterNoHeader().
  */