code: func (a *FlagArray) UnmarshalYAML(unmarshal func(interface{}) error) error {
  	var flags []string
  	if err := unmarshal(&flags); err != nil {
  		var flagstr string
  		if err := unmarshal(&flagstr); err != nil {
  			return err
  		}
  		*a = strings.Fields(flagstr)
  	} else {
  		*a = flags
  	}
  	return nil
  }
docs: // UnmarshalYAML is a custom unmarshaler that wraps strings in arrays