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 // template <class T>
13 //   constexpr
14 //   optional<typename decay<T>::type>
15 //   make_optional(T&& v);
16 
17 #include <experimental/optional>
18 #include <string>
19 #include <memory>
20 #include <cassert>
21 
22 int main()
23 {
24 #if _LIBCPP_STD_VER > 11
25     using std::experimental::optional;
26     using std::experimental::make_optional;
27 
28     {
29         optional<int> opt = make_optional(2);
30         assert(*opt == 2);
31     }
32     {
33         std::string s("123");
34         optional<std::string> opt = make_optional(s);
35         assert(*opt == s);
36     }
37     {
38         std::string s("123");
39         optional<std::string> opt = make_optional(std::move(s));
40         assert(*opt == "123");
41         assert(s.empty());
42     }
43     {
44         std::unique_ptr<int> s(new int(3));
45         optional<std::unique_ptr<int>> opt = make_optional(std::move(s));
46         assert(**opt == 3);
47         assert(s == nullptr);
48     }
49 #endif  // _LIBCPP_STD_VER > 11
50 }
51