Registry::parseControllerActions() 

\nn\t3::Registry()->parseControllerActions($controllerActionList = []); 

Parse list with 'ControllerName' => 'action,list,show' Always specify the full class path in the ::class notation. Take into account that before Typo3 10 only the simple class name (e.g. Main) is used as the key.

\nn\t3::Registry()->parseControllerActions(
    [\Nng\ExtName\Controller\MainController::class => 'index,list'],
);

| @return array

public function parseControllerActions( $controllerActionList = [] )
{
	return $controllerActionList;
}