#include <boost/core/empty_value.hpp>
template<class T>
struct derived
: boost::empty_value<T> {
typedef typename boost::empty_value<T>::type type;
derived(boost::empty_init_t e)
: boost::empty_value<T>(e) { }
};
struct outer {
struct inner_empty { };
struct inner_non_empty {
inner_non_empty()
: value() { }
int value;
};
};
void test()
{
const boost::empty_value<outer> x1(boost::empty_init);
(void)x1;
const boost::empty_value<outer::inner_empty> x2(boost::empty_init);
(void)x2;
const boost::empty_value<outer::inner_non_empty> x3(boost::empty_init);
(void)x3;
const derived<outer> x4(boost::empty_init);
(void)x4;
const derived<outer::inner_empty> x5(boost::empty_init);
(void)x5;
const derived<outer::inner_non_empty> x6(boost::empty_init);
(void)x6;
}