code: func (rs RepositoryScope) String() string {
  	repoType := "repository"
  	// Keep existing format for image class to maintain backwards compatibility
  	// with authorization servers which do not support the expanded grammar.
  	if rs.Class != "" && rs.Class != "image" {
  		repoType = fmt.Sprintf("%s(%s)", repoType, rs.Class)
  	}
  	return fmt.Sprintf("%s:%s:%s", repoType, rs.Repository, strings.Join(rs.Actions, ","))
  }
docs: // String returns the string representation of the repository
  // using the scope grammar