#include <iostream>
#include <vector>
#include <string>
#include <memory>
#include <map>

using namespace std;

struct ptrwrap
{
    unique_ptr<int> foo;
};

template <typename T>
struct holder
{
    holder() = default;

    holder(const holder& b)
        : t(b.t)
    {
    }

    holder(holder&& b)
        : t(std::move(b.t))
    {
    }

    holder& operator=(const holder& h)
    {
        t = h.t;
        return *this;
    }

    holder& operator=(holder&& h)
    {
        t = std::move(h.t);
        return *this;
    }

    T t;
};

struct y_u_no_elision
{
    holder<ptrwrap> elem;
};

typedef map<std::string, y_u_no_elision> mymap;

mymap foo();

int main()
{
    auto m = foo();
    m = foo();
    return 0;
}