/**
  * Helper function to format the min/max rules
  *
  * @param $field
  * @return string formatted (i.e. "min:2|max:20")
  */
 private function betweenFormatter($field)
 {
     return 'between:' . Project::attributeLengths()[$field]['min'] . ',' . Project::attributeLengths()[$field]['max'];
 }