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> constexpr bool operator!=(const optional<T>& x, const T& v);
13 // template <class T> constexpr bool operator!=(const T& v, const optional<T>& x);
14 
15 #include <experimental/optional>
16 
17 #if _LIBCPP_STD_VER > 11
18 
19 using std::experimental::optional;
20 
21 struct X
22 {
23     int i_;
24 
XX25     constexpr X(int i) : i_(i) {}
26 };
27 
operator ==(const X & lhs,const X & rhs)28 constexpr bool operator == ( const X &lhs, const X &rhs )
29     { return lhs.i_ == rhs.i_ ; }
30 
31 #endif
32 
main()33 int main()
34 {
35 #if _LIBCPP_STD_VER > 11
36     {
37     typedef X T;
38     typedef optional<T> O;
39 
40     constexpr T val(2);
41     constexpr O o1;       // disengaged
42     constexpr O o2{1};    // engaged
43     constexpr O o3{val};  // engaged
44 
45     static_assert (  (o1 != T(1)), "" );
46     static_assert ( !(o2 != T(1)), "" );
47     static_assert (  (o3 != T(1)), "" );
48     static_assert ( !(o3 != T(2)), "" );
49     static_assert ( !(o3 != val),  "" );
50 
51     static_assert (  (T(1) != o1), "" );
52     static_assert ( !(T(1) != o2), "" );
53     static_assert (  (T(1) != o3), "" );
54     static_assert ( !(T(2) != o3), "" );
55     static_assert ( !(val  != o3), "" );
56     }
57 #endif
58 }
59