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 optional<U>& y);
14
15 #include <optional>
16
17 using std::optional;
18
19 struct X {
20 int i_;
21
XX22 constexpr X(int i) : i_(i) {}
23 };
24
operator <=(const X & lhs,const X & rhs)25 constexpr bool operator<=(const X& lhs, const X& rhs) {
26 return lhs.i_ <= rhs.i_;
27 }
28
main()29 int main() {
30 {
31 typedef optional<X> O;
32
33 constexpr O o1; // disengaged
34 constexpr O o2; // disengaged
35 constexpr O o3{1}; // engaged
36 constexpr O o4{2}; // engaged
37 constexpr O o5{1}; // engaged
38
39 static_assert((o1 <= o1), "");
40 static_assert((o1 <= o2), "");
41 static_assert((o1 <= o3), "");
42 static_assert((o1 <= o4), "");
43 static_assert((o1 <= o5), "");
44
45 static_assert((o2 <= o1), "");
46 static_assert((o2 <= o2), "");
47 static_assert((o2 <= o3), "");
48 static_assert((o2 <= o4), "");
49 static_assert((o2 <= o5), "");
50
51 static_assert(!(o3 <= o1), "");
52 static_assert(!(o3 <= o2), "");
53 static_assert((o3 <= o3), "");
54 static_assert((o3 <= o4), "");
55 static_assert((o3 <= o5), "");
56
57 static_assert(!(o4 <= o1), "");
58 static_assert(!(o4 <= o2), "");
59 static_assert(!(o4 <= o3), "");
60 static_assert((o4 <= o4), "");
61 static_assert(!(o4 <= o5), "");
62
63 static_assert(!(o5 <= o1), "");
64 static_assert(!(o5 <= o2), "");
65 static_assert((o5 <= o3), "");
66 static_assert((o5 <= o4), "");
67 static_assert((o5 <= o5), "");
68 }
69 {
70 using O1 = optional<int>;
71 using O2 = optional<long>;
72 constexpr O1 o1(42);
73 static_assert(o1 <= O2(42), "");
74 static_assert(!(O2(101) <= o1), "");
75 }
76 {
77 using O1 = optional<int>;
78 using O2 = optional<const int>;
79 constexpr O1 o1(42);
80 static_assert(o1 <= O2(42), "");
81 static_assert(!(O2(101) <= o1), "");
82 }
83 }
84