public function pop($queueName)
    {
        $cache = $this->get($queueName);

        if (!$cache->isEmpty()) {
            return $cache->dequeue();
        }
    }
public function pop($queueName)
    {
        $cache = $this->get($queueName);

        if (!$cache->isEmpty()) {
            return $cache->dequeue();
        }
    }
public function pop ( $ queueName ) { $ cache = $ this -> get ( $ queueName ) ; if ( ! $ cache -> isEmpty ( ) ) { return $ cache -> dequeue ( ) ; } }
Get the next message in line. Or nothing if there is no more
in the cache.

@param string $queueName

@return array|null
Get the next message in line . Or nothing if there is no more in the cache .