public static function is_empty_subsystem($component) {
        if (strpos($component, 'core_') === 0) {
            if (null === \core_component::get_subsystem_directory(substr($component, 5))) {
                // This is a subsystem without a directory.
                return true;
            }
        }

        return false;
    }
public static function is_empty_subsystem($component) {
        if (strpos($component, 'core_') === 0) {
            if (null === \core_component::get_subsystem_directory(substr($component, 5))) {
                // This is a subsystem without a directory.
                return true;
            }
        }

        return false;
    }
public static function is_empty_subsystem ( $ component ) { if ( strpos ( $ component , 'core_' ) === 0 ) { if ( null === \ core_component :: get_subsystem_directory ( substr ( $ component , 5 ) ) ) { // This is a subsystem without a directory. return true ; } } return false ; }
Return whether this is an 'empty' subsystem - that is, a subsystem without a directory.

@param  string $component Frankenstyle component name.
@return string The key to retrieve the language string for the null provider reason.
Return whether this is an empty subsystem - that is a subsystem without a directory .