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//===----------------------------------------------------------------------===//
//
// 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
// <iterator>
//
// template <class T, size_t N> constexpr T* begin(T (&array)[N]) noexcept;
// template <class T, size_t N> constexpr T* end(T (&array)[N]) noexcept;
//
// template <class T, size_t N> constexpr reverse_iterator<T*> rbegin(T (&array)[N]); // C++14, constexpr since C++17
// template <class T, size_t N> constexpr reverse_iterator<T*> rend(T (&array)[N]); // C++14, constexpr since C++17
#include <cassert>
#include <iterator>
#include "test_macros.h"
TEST_CONSTEXPR_CXX14 bool test() {
int a[] = {1, 2, 3};
const auto& ca = a;
// std::begin(T (&)[N]) / std::end(T (&)[N])
{
ASSERT_NOEXCEPT(std::begin(a));
ASSERT_SAME_TYPE(decltype(std::begin(a)), int*);
assert(std::begin(a) == a);
ASSERT_NOEXCEPT(std::end(a));
ASSERT_SAME_TYPE(decltype(std::end(a)), int*);
assert(std::end(a) == a + 3);
// kind of overkill since it follows from the definition, but worth testing
ASSERT_NOEXCEPT(std::begin(ca));
ASSERT_SAME_TYPE(decltype(std::begin(ca)), const int*);
assert(std::begin(ca) == ca);
ASSERT_NOEXCEPT(std::end(ca));
ASSERT_SAME_TYPE(decltype(std::end(ca)), const int*);
assert(std::end(ca) == ca + 3);
}
return true;
}
TEST_CONSTEXPR_CXX17 bool test_r() {
#if TEST_STD_VER >= 14
int a[] = {1, 2, 3};
const auto& ca = a;
// std::rbegin(T (&)[N]) / std::rend(T (&)[N])
{
ASSERT_SAME_TYPE(decltype(std::rbegin(a)), std::reverse_iterator<int*>);
assert(std::rbegin(a).base() == a + 3);
ASSERT_SAME_TYPE(decltype(std::rend(a)), std::reverse_iterator<int*>);
assert(std::rend(a).base() == a);
// kind of overkill since it follows from the definition, but worth testing
ASSERT_SAME_TYPE(decltype(std::rbegin(ca)), std::reverse_iterator<const int*>);
assert(std::rbegin(ca).base() == ca + 3);
ASSERT_SAME_TYPE(decltype(std::rend(ca)), std::reverse_iterator<const int*>);
assert(std::rend(ca).base() == ca);
}
#endif
return true;
}
int main(int, char**) {
test();
test_r();
#if TEST_STD_VER >= 14
static_assert(test(), "");
#endif
#if TEST_STD_VER >= 17
static_assert(test_r(), "");
#endif
// Make sure std::begin(T (&)[N]) and std::end(T (&)[N]) are constexpr in C++11 too (see LWG2280).
{
static constexpr int a[] = {1, 2, 3};
constexpr auto b = std::begin(a);
assert(b == a);
constexpr auto e = std::end(a);
assert(e == a + 3);
}
return 0;
}
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