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 // <array>
10 
11 // const_reference operator[](size_type) const; // constexpr in C++14
12 // Libc++ marks it as noexcept
13 
14 #include <array>
15 #include <cassert>
16 
17 #include "test_macros.h"
18 
19 TEST_CONSTEXPR_CXX14 bool tests()
20 {
21     {
22         typedef double T;
23         typedef std::array<T, 3> C;
24         C const c = {1, 2, 3.5};
25         LIBCPP_ASSERT_NOEXCEPT(c[0]);
26         ASSERT_SAME_TYPE(C::const_reference, decltype(c[0]));
27         C::const_reference r1 = c[0];
28         assert(r1 == 1);
29         C::const_reference r2 = c[2];
30         assert(r2 == 3.5);
31     }
32     // Test operator[] "works" on zero sized arrays
33     {
34         {
35             typedef double T;
36             typedef std::array<T, 0> C;
37             C const c = {};
38             LIBCPP_ASSERT_NOEXCEPT(c[0]);
39             ASSERT_SAME_TYPE(C::const_reference, decltype(c[0]));
40             if (c.size() > (0)) { // always false
41                 C::const_reference r = c[0];
42                 (void)r;
43             }
44         }
45         {
46             typedef double T;
47             typedef std::array<T const, 0> C;
48             C const c = {};
49             LIBCPP_ASSERT_NOEXCEPT(c[0]);
50             ASSERT_SAME_TYPE(C::const_reference, decltype(c[0]));
51             if (c.size() > (0)) { // always false
52               C::const_reference r = c[0];
53               (void)r;
54             }
55         }
56     }
57 
58     return true;
59 }
60 
61 int main(int, char**)
62 {
63     tests();
64 #if TEST_STD_VER >= 14
65     static_assert(tests(), "");
66 #endif
67   return 0;
68 }
69