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// UNSUPPORTED: c++98, c++03, c++11, c++14
11// <optional>
12
13// template <class T, class U> constexpr bool operator!=(const optional<T>& x, const U& v);
14// template <class T, class U> constexpr bool operator!=(const U& v, const optional<T>& x);
15
16#include <optional>
17
18using std::optional;
19
20struct X {
21  int i_;
22
23  constexpr X(int i) : i_(i) {}
24};
25
26constexpr bool operator!=(const X& lhs, const X& rhs) {
27  return lhs.i_ != rhs.i_;
28}
29
30int main() {
31  {
32    typedef X T;
33    typedef optional<T> O;
34
35    constexpr T val(2);
36    constexpr O o1;      // disengaged
37    constexpr O o2{1};   // engaged
38    constexpr O o3{val}; // engaged
39
40    static_assert((o1 != T(1)), "");
41    static_assert(!(o2 != T(1)), "");
42    static_assert((o3 != T(1)), "");
43    static_assert(!(o3 != T(2)), "");
44    static_assert(!(o3 != val), "");
45
46    static_assert((T(1) != o1), "");
47    static_assert(!(T(1) != o2), "");
48    static_assert((T(1) != o3), "");
49    static_assert(!(T(2) != o3), "");
50    static_assert(!(val != o3), "");
51  }
52  {
53    using O = optional<int>;
54    constexpr O o1(42);
55    static_assert(o1 != 101l, "");
56    static_assert(!(42l != o1), "");
57  }
58  {
59    using O = optional<const int>;
60    constexpr O o1(42);
61    static_assert(o1 != 101, "");
62    static_assert(!(42 != o1), "");
63  }
64}
65