1//===----------------------------------------------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is dual licensed under the MIT and the University of Illinois Open 6// Source Licenses. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9 10// UNSUPPORTED: c++98, c++03, c++11, c++14 11// <optional> 12 13// template <class T> 14// class optional 15// { 16// public: 17// typedef T value_type; 18// ... 19 20#include <optional> 21#include <type_traits> 22 23using std::optional; 24 25template <class Opt, class T> 26void 27test() 28{ 29 static_assert(std::is_same<typename Opt::value_type, T>::value, ""); 30} 31 32int main() 33{ 34 test<optional<int>, int>(); 35 test<optional<const int>, const int>(); 36 test<optional<double>, double>(); 37 test<optional<const double>, const double>(); 38} 39