//===----------------------------------------------------------------------===// // // The LLVM Compiler Infrastructure // // This file is dual licensed under the MIT and the University of Illinois Open // Source Licenses. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // <optional> // struct in_place_t{}; // constexpr in_place_t in_place{}; #include <experimental/optional> #include <type_traits> #if _LIBCPP_STD_VER > 11 using std::experimental::optional; using std::experimental::in_place_t; using std::experimental::in_place; constexpr int test(const in_place_t&) { return 3; } #endif int main() { #if _LIBCPP_STD_VER > 11 static_assert((std::is_class<in_place_t>::value), ""); static_assert((std::is_empty<in_place_t>::value), ""); static_assert(test(in_place) == 3, ""); #endif }