public function canVisit(Criterion $criterion)
    {
        return
            $criterion instanceof Criterion\FieldRelation &&
            (($criterion->operator ?: Operator::IN) === Operator::IN ||
                $criterion->operator === Operator::CONTAINS);
    }
public function canVisit(Criterion $criterion)
    {
        return
            $criterion instanceof Criterion\FieldRelation &&
            (($criterion->operator ?: Operator::IN) === Operator::IN ||
                $criterion->operator === Operator::CONTAINS);
    }
public function canVisit ( Criterion $ criterion ) { return $ criterion instanceof Criterion \ FieldRelation && ( ( $ criterion -> operator ? : Operator :: IN ) === Operator :: IN || $ criterion -> operator === Operator :: CONTAINS ) ; }
Check if visitor is applicable to current criterion.

@param Criterion $criterion

@return bool
Check if visitor is applicable to current criterion .