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 // <optional> 11 12 // struct in_place_t{}; 13 // constexpr in_place_t in_place{}; 14 15 #include <experimental/optional> 16 #include <type_traits> 17 18 #if _LIBCPP_STD_VER > 11 19 20 using std::experimental::optional; 21 using std::experimental::in_place_t; 22 using std::experimental::in_place; 23 24 constexpr 25 int 26 test(const in_place_t&) 27 { 28 return 3; 29 } 30 31 #endif 32 33 int main() 34 { 35 #if _LIBCPP_STD_VER > 11 36 37 static_assert((std::is_class<in_place_t>::value), ""); 38 static_assert((std::is_empty<in_place_t>::value), ""); 39 40 static_assert(test(in_place) == 3, ""); 41 #endif 42 } 43
