relation property

Implementation

NSLayoutRelation get relation {
  objc.checkOsVersionInternal('NSLayoutConstraint.relation', iOS: (false, (6, 0, 0)), macOS: (false, (10, 7, 0)));
  final _ret = _objc_msgSend_utwjq8(this.ref.pointer, _sel_relation);
  return NSLayoutRelation.fromValue(_ret);
}