[AggregationBuilder] - check empty array after lookup

[vencakrecl]

Is there better way how to write this $match?

                 $qb->lookup(Document::class)
                        ->localField('_id')
                        ->foreignField('object_id')
                        ->alias('items')

                        ->match()
                        ->field('$expr')->equals([
                            '$gt' => [
                                ['$size' => '$items'],
                                0,
                            ],
                        ]);