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// { dg-do compile { target c++17 } }
// { dg-skip-if "requires hosted libstdc++ for string" { ! hostedlib } }
#include <memory>
#include <tuple>
#include <string>
struct X : private std::shared_ptr<int>
{
std::string fun_payload;
};
template<int N> std::string& get(X& x)
{
if constexpr(N==0) return x.fun_payload;
}
namespace std {
template<> class tuple_size<X> : public std::integral_constant<int, 1> {};
template<> class tuple_element<0, X> {public: using type = std::string;};
}
struct X2 : private std::shared_ptr<int>
{
int fun_payload;
template <class T> void get();
};
template<int N> int& get(X2& x)
{
if constexpr(N==0) return x.fun_payload;
}
namespace std {
template<> class tuple_size<X2> : public std::integral_constant<int, 1> {};
template<> class tuple_element<0, X2> {public: using type = int;};
}
class X3
{
double fun_payload;
public:
template <int N> double& get()
{
if constexpr(N==0) return fun_payload;
}
};
namespace std {
template<> class tuple_size<X3> : public std::integral_constant<int, 1> {};
template<> class tuple_element<0, X3> {public: using type = double;};
}
int main()
{
X x;
auto& [b1] = x;
X2 x2;
auto& [b2] = x2;
X3 x3;
auto& [b3] = x3;
}
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