code: protected function transformParam($param, $k)
      {
          if (isset($this->routeMapParse[$k][$param]) and !is_array($this->routeMapParse[$k][$param])) {
              return $this->routeMapParse[$k][$param];
          } else {
              return '(.+?)';
          }
      }
docs: Prepares the regexp
  
  @param string $param
  @param string $k
  
  @return string