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 {
38 typedef X T;
39 typedef optional<T> O;
40
41 constexpr T val(2);
42 constexpr O o1; // disengaged
43 constexpr O o2{1}; // engaged
44 constexpr O o3{val}; // engaged
45
46 static_assert ( (o1 <= T(1)), "" );
47 static_assert ( (o2 <= T(1)), "" ); // equal
48 static_assert ( !(o3 <= T(1)), "" );
49 static_assert ( (o2 <= val), "" );
50 static_assert ( (o3 <= val), "" ); // equal
51 static_assert ( (o3 <= T(3)), "" );
52
53 static_assert ( !(T(1) <= o1), "" );
54 static_assert ( (T(1) <= o2), "" ); // equal
55 static_assert ( (T(1) <= o3), "" );
56 static_assert ( !(val <= o2), "" );
57 static_assert ( (val <= o3), "" ); // equal
58 static_assert ( !(T(3) <= o3), "" );
59 }
60 #endif
61 }
62