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
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
// <utility>
// template <class T1, class T2> struct pair
// template <class U1, class U2>
// constexpr const pair& operator=(pair<U1, U2>&& p) const;
#include <cassert>
#include <utility>
#include "test_macros.h"
#include "copy_move_types.h"
// Constraints:
// is_assignable<const first_type&, U1> is true and
// is_assignable<const second_type&, U2> is true.
// clang-format off
static_assert( std::is_assignable_v<const std::pair<int&&, int&&>&,
std::pair<long&&, long&&>&&>);
static_assert(!std::is_assignable_v<const std::pair<int, int>&,
std::pair<long, long>&&>);
static_assert(!std::is_assignable_v<const std::pair<int, int&&>&,
std::pair<long, long&&>&&>);
static_assert(!std::is_assignable_v<const std::pair<int&&, int>&,
std::pair<long&&, long>&&>);
static_assert(std::is_assignable_v<
const std::pair<AssignableFrom<ConstMoveAssign>, AssignableFrom<ConstMoveAssign>>&,
std::pair<ConstMoveAssign, ConstMoveAssign>&&>);
static_assert(!std::is_assignable_v<
const std::pair<AssignableFrom<MoveAssign>, AssignableFrom<MoveAssign>>&,
std::pair<MoveAssign, MoveAssign>&&>);
// clang-format on
constexpr bool test() {
// reference types
{
int i1 = 1;
int i2 = 2;
long j1 = 3;
long j2 = 4;
std::pair<int&&, int&&> p1{std::move(i1), std::move(i2)};
const std::pair<long&&, long&&> p2{std::move(j1), std::move(j2)};
p2 = std::move(p1);
assert(p2.first == 1);
assert(p2.second == 2);
}
// user defined const move assignment
{
std::pair<ConstMoveAssign, ConstMoveAssign> p1{1, 2};
const std::pair<AssignableFrom<ConstMoveAssign>, AssignableFrom<ConstMoveAssign>> p2{3, 4};
p2 = std::move(p1);
assert(p2.first.v.val == 1);
assert(p2.second.v.val == 2);
}
// The correct assignment operator of the underlying type is used
{
std::pair<TracedAssignment, TracedAssignment> t1{};
const std::pair<AssignableFrom<TracedAssignment>, AssignableFrom<TracedAssignment>> t2{};
t2 = std::move(t1);
assert(t2.first.v.constMoveAssign == 1);
assert(t2.second.v.constMoveAssign == 1);
}
return true;
}
int main(int, char**) {
test();
// gcc cannot have mutable member in constant expression
#if !defined(TEST_COMPILER_GCC)
static_assert(test());
#endif
return 0;
}
|
