code: public function __isset($name)
      {
          try {
              return $this->__get($name) !== null;
          } catch (\Throwable $t) {
              return false;
          } catch (\Exception $e) {
              return false;
          }
      }
docs: Checks if a property value is null.
  This method overrides the parent implementation by checking if the named attribute is `null` or not.
  @param string $name the property name or the event name
  @return bool whether the property value is null