/**
* Get the regex for matching the domain part of this route.
*
* @param \Illuminate\Routing\Route $route
* @return string
*/
private function getDomainRegex($route)
{
ReflectionHelper::invokePrivateMethod($route, 'compileRoute');
$compiledRoute = ReflectionHelper::readPrivateProperty($route, 'compiled');
return $compiledRoute->getHostRegex();
}
