public function getBacklogLength() : int
    {
        return array_reduce(
            $this->commandQueue,
            function ($a, CommandInterface $command) {
                if ($command instanceof Query || $command instanceof Sync) {
                    $a++;
                }
                return $a;
            },
            0);
    }
public function getBacklogLength() : int
    {
        return array_reduce(
            $this->commandQueue,
            function ($a, CommandInterface $command) {
                if ($command instanceof Query || $command instanceof Sync) {
                    $a++;
                }
                return $a;
            },
            0);
    }
public function getBacklogLength ( ) : int { return array_reduce ( $ this -> commandQueue , function ( $ a , CommandInterface $ command ) { if ( $ command instanceof Query || $ command instanceof Sync ) { $ a ++ ; } return $ a ; } , 0 ) ; }
Get Query commands queue length
@return int
Get Query commands queue length