97 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++0310 11// <iterator>12//13// template <class T, size_t N> constexpr T* begin(T (&array)[N]) noexcept;14// template <class T, size_t N> constexpr T* end(T (&array)[N]) noexcept;15//16// template <class T, size_t N> constexpr reverse_iterator<T*> rbegin(T (&array)[N]); // C++14, constexpr since C++1717// template <class T, size_t N> constexpr reverse_iterator<T*> rend(T (&array)[N]); // C++14, constexpr since C++1718 19#include <cassert>20#include <iterator>21 22#include "test_macros.h"23 24TEST_CONSTEXPR_CXX14 bool test() {25 int a[] = {1, 2, 3};26 const auto& ca = a;27 28 // std::begin(T (&)[N]) / std::end(T (&)[N])29 {30 ASSERT_NOEXCEPT(std::begin(a));31 ASSERT_SAME_TYPE(decltype(std::begin(a)), int*);32 assert(std::begin(a) == a);33 34 ASSERT_NOEXCEPT(std::end(a));35 ASSERT_SAME_TYPE(decltype(std::end(a)), int*);36 assert(std::end(a) == a + 3);37 38 // kind of overkill since it follows from the definition, but worth testing39 ASSERT_NOEXCEPT(std::begin(ca));40 ASSERT_SAME_TYPE(decltype(std::begin(ca)), const int*);41 assert(std::begin(ca) == ca);42 43 ASSERT_NOEXCEPT(std::end(ca));44 ASSERT_SAME_TYPE(decltype(std::end(ca)), const int*);45 assert(std::end(ca) == ca + 3);46 }47 48 return true;49}50 51TEST_CONSTEXPR_CXX17 bool test_r() {52#if TEST_STD_VER >= 1453 int a[] = {1, 2, 3};54 const auto& ca = a;55 56 // std::rbegin(T (&)[N]) / std::rend(T (&)[N])57 {58 ASSERT_SAME_TYPE(decltype(std::rbegin(a)), std::reverse_iterator<int*>);59 assert(std::rbegin(a).base() == a + 3);60 61 ASSERT_SAME_TYPE(decltype(std::rend(a)), std::reverse_iterator<int*>);62 assert(std::rend(a).base() == a);63 64 // kind of overkill since it follows from the definition, but worth testing65 ASSERT_SAME_TYPE(decltype(std::rbegin(ca)), std::reverse_iterator<const int*>);66 assert(std::rbegin(ca).base() == ca + 3);67 68 ASSERT_SAME_TYPE(decltype(std::rend(ca)), std::reverse_iterator<const int*>);69 assert(std::rend(ca).base() == ca);70 }71#endif72 73 return true;74}75 76int main(int, char**) {77 test();78 test_r();79#if TEST_STD_VER >= 1480 static_assert(test(), "");81#endif82#if TEST_STD_VER >= 1783 static_assert(test_r(), "");84#endif85 86 // Make sure std::begin(T (&)[N]) and std::end(T (&)[N]) are constexpr in C++11 too (see LWG2280).87 {88 static constexpr int a[] = {1, 2, 3};89 constexpr auto b = std::begin(a);90 assert(b == a);91 constexpr auto e = std::end(a);92 assert(e == a + 3);93 }94 95 return 0;96}97