1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
|
//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11, c++14
// <optional>
// template <class T> constexpr bool operator==(const optional<T>& x, const T& v);
// template <class T> constexpr bool operator==(const T& v, const optional<T>& x);
#include <optional>
using std::optional;
struct X
{
int i_;
constexpr X(int i) : i_(i) {}
};
constexpr bool operator == ( const X &lhs, const X &rhs )
{ return lhs.i_ == rhs.i_ ; }
int main()
{
{
typedef X T;
typedef optional<T> O;
constexpr T val(2);
constexpr O o1; // disengaged
constexpr O o2{1}; // engaged
constexpr O o3{val}; // engaged
static_assert ( !(o1 == T(1)), "" );
static_assert ( (o2 == T(1)), "" );
static_assert ( !(o3 == T(1)), "" );
static_assert ( (o3 == T(2)), "" );
static_assert ( (o3 == val), "" );
static_assert ( !(T(1) == o1), "" );
static_assert ( (T(1) == o2), "" );
static_assert ( !(T(1) == o3), "" );
static_assert ( (T(2) == o3), "" );
static_assert ( (val == o3), "" );
}
}
|
