Rx\Observable::subscribeCallback PHP Method

    public function subscribeCallback(callable $onNext = null, callable $onError = null, callable $onCompleted = null, SchedulerInterface $scheduler = null)
    {
        $observer = new CallbackObserver($onNext, $onError, $onCompleted);
        return $this->subscribe($observer, $scheduler);
    }

 public function observe(Observable $observable)
 {
     return $observable->subscribeCallback(function (Event $event) {
         //$name = basename(str_replace('\\', '/', (is_object($event) ? get_class($event) : $event)));
         //\Log::info("{$this->preposition} {$name} {$event->name}", $event->labels);
         if ($this->verbosity == 4) {
             $this->dump($event->data);
         }
     }, function ($e) {
         if ($this->verbosity == 4) {
             //\Log::error("{$this->preposition} {$e->getMessage()}");
         } else {
             //\Log::error("{$this->preposition} {$e->getMessage()}", [$e]);
         }
     }, function () {
         //\Log::warning("{$this->preposition} event stream is complete");
     });
 }