code: public function render($action, $package = NULL, $subpackage = NULL, $controller = NULL) {
  		if ($package === NULL) {
  			$package = $this->request->getControllerPackageKey();
  		}
  		if (($package === NULL) && ($subpackage === NULL)) {
  			$subpackage = $this->request->getControllerSubpackageKey();
  		}
  		if ($controller === NULL) {
  			$controller = $this->request->getControllerName();
  		}
  
  		if ($this->hasAccessToAction($package, $subpackage, $controller, $action)) {
  			return $this->renderThenChild();
  		}
  		return $this->renderElseChild();
  	}
docs: renders <f:then> child if access to the given resource is allowed, otherwise renders <f:else> child.
  
  @param null $package
  @param null $subpackage
  @param null $controller
  @param $action
  @internal param string $resource Policy resource
  @return string the rendered string
  @api