All classes that implement MessengerInterface in Drupal 8
- class \Drupal\Core\Messenger\LegacyMessenger implements MessengerInterface
- class \Drupal\Core\Messenger\Messenger implements MessengerInterface
- class \Drupal\Tests\rules\Unit\TestMessenger implements MessengerInterface
- class \Drupal\Tests\uc_cart_links\Unit\TestMessenger implements MessengerInterface
- class \Drupal\feeds_ex\Messenger\TestMessenger
- class \Drupal\social_demo\Messenger
- class \Drupal\social_demo\Messenger