#include <boost/python.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/weak_ptr.hpp>
#include <iostream>

using namespace boost;

class A {
  public:
    int i;
    A(int _i) : i(_i) {}
};

weak_ptr<A> wpa;

void output(shared_ptr<A>& ptr) {
  wpa = ptr;
  std::cout << "output: " << ptr->i << std::endl;
}

void output_weak() {
  shared_ptr<A> spa;
  spa = wpa.lock();
  if (!spa)
      std::cout << "output: none " << std::endl;
  else
      std::cout << "output: " << spa->i << std::endl;
}

BOOST_PYTHON_MODULE(tester) {
  python::class_<A, shared_ptr<A> >("A", python::init<int>())
    .def_readwrite("i", &A::i)
    ;
  python::def("output", output);
  python::def("output_weak", output_weak);
}