//===----------------------------------------------------------------------===// // // 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. // //===----------------------------------------------------------------------===// // // template // constexpr // optional::type> // make_optional(T&& v); #include #include #include #include int main() { #if _LIBCPP_STD_VER > 11 using std::experimental::optional; using std::experimental::make_optional; { optional opt = make_optional(2); assert(*opt == 2); } { std::string s("123"); optional opt = make_optional(s); assert(*opt == s); } { std::string s("123"); optional opt = make_optional(std::move(s)); assert(*opt == "123"); assert(s.empty()); } { std::unique_ptr s(new int(3)); optional> opt = make_optional(std::move(s)); assert(**opt == 3); assert(s == nullptr); } #endif // _LIBCPP_STD_VER > 11 }