How to use keep_alive with a function returning different types of objects

[ozars]

I have some code similar to this:

struct A {
  std::vector<int> x;
  int y;
};

PYBIND11_MODULE(example, m) {

  py::class<A>(m, "A").def(
      "__getitem__",
      [](A& a, int64_t i) -> py::object {
        switch (i) {
          case 0: return py::array_t(a.x.size(), a.x.data());
          case 1: return py::cast(a.y);
          default: throw py::index_error("index out of range");
        }
      },
      py::keep_alive<0, 1>{});

}

Calling a[0] works as expected. a[1] fails with RuntimeError: Could not allocate weak reference!, I assume because assigning an int object as nurse doesn't make sense.

What is the recommended way for dealing with both indices while keeping the reference alive?

[ozars]

Moved question to https://stackoverflow.com/questions/68960270/