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
12 // <optional>
13
14 // template <class T> constexpr bool operator<=(const optional<T>& x, nullopt_t) noexcept;
15 // template <class T> constexpr bool operator<=(nullopt_t, const optional<T>& x) noexcept;
16
17 #include <optional>
18
main()19 int main()
20 {
21 using std::optional;
22 using std::nullopt_t;
23 using std::nullopt;
24
25 {
26 typedef int T;
27 typedef optional<T> O;
28
29 constexpr O o1; // disengaged
30 constexpr O o2{1}; // engaged
31
32 static_assert ( (nullopt <= o1), "" );
33 static_assert ( (nullopt <= o2), "" );
34 static_assert ( (o1 <= nullopt), "" );
35 static_assert ( !(o2 <= nullopt), "" );
36
37 static_assert (noexcept(nullopt <= o1), "");
38 static_assert (noexcept(o1 <= nullopt), "");
39 }
40 }
41