Neos\Flow\Package\MetaData\SystemConstraint::__construct PHP Method

    public function __construct($constraintType, $type, $value = null, $minVersion = null, $maxVersion = null)
    {
        if ($value === '') {
            $value = null;
        }
        parent::__construct($constraintType, $value, $minVersion, $maxVersion);
        $this->type = $type;
    }