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 U> optional<T>& operator=(U&& v);
13
14 #include <experimental/optional>
15 #include <type_traits>
16 #include <cassert>
17 #include <memory>
18
19 #if _LIBCPP_STD_VER > 11
20
21 using std::experimental::optional;
22
23 struct X
24 {
25 };
26
27 #endif // _LIBCPP_STD_VER > 11
28
main()29 int main()
30 {
31 #if _LIBCPP_STD_VER > 11
32 static_assert(std::is_assignable<optional<int>, int>::value, "");
33 static_assert(std::is_assignable<optional<int>, int&>::value, "");
34 static_assert(std::is_assignable<optional<int>&, int>::value, "");
35 static_assert(std::is_assignable<optional<int>&, int&>::value, "");
36 static_assert(std::is_assignable<optional<int>&, const int&>::value, "");
37 static_assert(!std::is_assignable<const optional<int>&, const int&>::value, "");
38 static_assert(!std::is_assignable<optional<int>, X>::value, "");
39 {
40 optional<int> opt;
41 opt = 1;
42 assert(static_cast<bool>(opt) == true);
43 assert(*opt == 1);
44 }
45 {
46 optional<int> opt;
47 const int i = 2;
48 opt = i;
49 assert(static_cast<bool>(opt) == true);
50 assert(*opt == i);
51 }
52 {
53 optional<int> opt(3);
54 const int i = 2;
55 opt = i;
56 assert(static_cast<bool>(opt) == true);
57 assert(*opt == i);
58 }
59 {
60 optional<std::unique_ptr<int>> opt;
61 opt = std::unique_ptr<int>(new int(3));
62 assert(static_cast<bool>(opt) == true);
63 assert(**opt == 3);
64 }
65 {
66 optional<std::unique_ptr<int>> opt(std::unique_ptr<int>(new int(2)));
67 opt = std::unique_ptr<int>(new int(3));
68 assert(static_cast<bool>(opt) == true);
69 assert(**opt == 3);
70 }
71 #endif // _LIBCPP_STD_VER > 11
72 }
73