1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9// constexpr bool operator[](size_t pos) const; // constexpr since C++23
10
11// XFAIL: FROZEN-CXX03-HEADERS-FIXME
12
13#include <bitset>
14#include <cassert>
15#include <cstddef>
16#include <vector>
17
18#include "../bitset_test_cases.h"
19#include "test_macros.h"
20
21template <std::size_t N>
22TEST_CONSTEXPR_CXX23 void test_index_const() {
23 std::vector<std::bitset<N> > const cases = get_test_cases<N>();
24 for (std::size_t c = 0; c != cases.size(); ++c) {
25 std::bitset<N> const v = cases[c];
26 if (v.size() > 0) {
27 assert(v[N / 2] == v.test(N / 2));
28 }
29 }
30#if !defined(_LIBCPP_VERSION) || defined(_LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL)
31 ASSERT_SAME_TYPE(decltype(cases[0][0]), bool);
32#else
33 ASSERT_SAME_TYPE(decltype(cases[0][0]), typename std::bitset<N>::__const_reference);
34#endif
35}
36
37TEST_CONSTEXPR_CXX23 bool test() {
38 test_index_const<0>();
39 test_index_const<1>();
40 test_index_const<31>();
41 test_index_const<32>();
42 test_index_const<33>();
43 test_index_const<63>();
44 test_index_const<64>();
45 test_index_const<65>();
46
47 std::bitset<1> set_;
48 set_[0] = false;
49 const auto& set = set_;
50 auto b = set[0];
51 set_[0] = true;
52#if !defined(_LIBCPP_VERSION) || defined(_LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL)
53 assert(!b);
54#else
55 assert(b);
56#endif
57
58 return true;
59}
60
61int main(int, char**) {
62 test();
63 test_index_const<1000>(); // not in constexpr because of constexpr evaluation step limits
64#if TEST_STD_VER > 20
65 static_assert(test());
66#endif
67
68 return 0;
69}
70

source code of libcxx/test/std/utilities/template.bitset/bitset.members/index_const.pass.cpp