code: func (cm *Meta) writeHash(h hash.Hash) error {
  	if _, err := h.Write([]byte{byte(cm.Chunk.Encoding())}); err != nil {
  		return err
  	}
  	if _, err := h.Write(cm.Chunk.Bytes()); err != nil {
  		return err
  	}
  	return nil
  }
docs: // writeHash writes the chunk encoding and raw data into the provided hash.