/**
  * Returns a concatenated path
  *
  * @param RouteInterface $resource
  *
  * @return string
  */
 protected function getPath(RouteInterface $resource)
 {
     if (strlen($this->pattern)) {
         return $resource->getPath() . RouteGeneratorInterface::PATH_PARAMS_SEPARATOR . $this->pattern;
     }
     return $resource->getPath();
 }