class A
{
public:
    const int (&get_array() const)[4] { return m_arr; }
    
    void set_array(int (&newArr)[4])
    {
        for (int i = 0; i < int(sizeof(newArr) / sizeof(int)); ++i)
            m_arr[i] = newArr[i];
    }

private:
    int m_arr[4];
};

typedef const int (&(A::*get_arr_fcn)() const)[4];

#include <boost/intrusive/list.hpp>

using namespace boost::intrusive;

struct mytag1;
struct mytag2;
struct linked
{
    typedef list_member_hook<tag<mytag1>, link_mode<auto_unlink> > hook1_t;
    typedef list_member_hook<tag<mytag2>, link_mode<safe_link> > hook2_t;
    hook1_t _hook1;
    hook2_t _hook2;
};
list<linked, member_hook<linked, linked::hook1_t, &linked::_hook1>,  constant_time_size<false> > list1;
list<linked, member_hook<linked, linked::hook2_t, &linked::_hook2>,  constant_time_size<false> > list2;