index method

Implementation

int? index() {
  var tmp0 = 0;
  tmp0 = _box.borrow();
  final tmp1 = _api._spaceDiffIndex(
    tmp0,
  );
  final tmp3 = tmp1.arg0;
  final tmp4 = tmp1.arg1;
  if (tmp3 == 0) {
    return null;
  }
  final tmp2 = tmp4;
  return tmp2;
}