/** * Return a simple lists string. * * @return null|string */ public function lists($column = null) { /* @var Relation $value */ $value = $this->object->getValue(); $related = $this->object->getRelatedModel(); /* @var EloquentCollection $relations */ if ($relations = $value->get()) { return implode(', ', $relations->lists($column ?: $related->getTitleName())); } return null; }