code: func (w yamlFrameWriter) Write(data []byte) (n int, err error) {
  	if _, err := w.w.Write([]byte("---\n")); err != nil {
  		return 0, err
  	}
  	return w.w.Write(data)
  }
docs: // Write separates each document with the YAML document separator (`---` followed by line
  // break). Writers must write well formed YAML documents (include a final line break).