//===----------------------------------------------------------------------===// // // 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> // constexpr explicit optional<T>::operator bool() const noexcept; #include <experimental/optional> #include <type_traits> #include <cassert> int main() { #if _LIBCPP_STD_VER > 11 using std::experimental::optional; { constexpr optional<int> opt; static_assert(!opt, ""); } { constexpr optional<int> opt(0); static_assert(opt, ""); } #endif // _LIBCPP_STD_VER > 11 }