Happyr\DoctrineSpecification\Filter\IsNull::__construct PHP Метод

public __construct ( string $field, string \| null $dqlAlias = null )
$field	string
$dqlAlias	string \| null

    public function __construct($field, $dqlAlias = null)
    {
        $this->field = $field;
        $this->dqlAlias = $dqlAlias;
    }

IsNull