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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
//
//===----------------------------------------------------------------------===//
// <array>
// UNSUPPORTED: c++03, c++11, c++14
// UNSUPPORTED: clang-5, apple-clang-9
// UNSUPPORTED: libcpp-no-deduction-guides
// Clang 5 will generate bad implicit deduction guides
// Specifically, for the copy constructor.
// template <class T, class... U>
// array(T, U...) -> array<T, 1 + sizeof...(U)>;
//
// Requires: (is_same_v<T, U> && ...) is true. Otherwise the program is ill-formed.
#include <array>
#include <cassert>
#include <cstddef>
// std::array is explicitly allowed to be initialized with A a = { init-list };.
// Disable the missing braces warning for this reason.
#include "disable_missing_braces_warning.h"
#include "test_macros.h"
constexpr bool tests()
{
// Test the explicit deduction guides
{
std::array arr{1,2,3}; // array(T, U...)
static_assert(std::is_same_v<decltype(arr), std::array<int, 3>>, "");
assert(arr[0] == 1);
assert(arr[1] == 2);
assert(arr[2] == 3);
}
{
const long l1 = 42;
std::array arr{1L, 4L, 9L, l1}; // array(T, U...)
static_assert(std::is_same_v<decltype(arr)::value_type, long>, "");
static_assert(arr.size() == 4, "");
assert(arr[0] == 1);
assert(arr[1] == 4);
assert(arr[2] == 9);
assert(arr[3] == l1);
}
// Test the implicit deduction guides
{
std::array<double, 2> source = {4.0, 5.0};
std::array arr(source); // array(array)
static_assert(std::is_same_v<decltype(arr), decltype(source)>, "");
static_assert(std::is_same_v<decltype(arr), std::array<double, 2>>, "");
assert(arr[0] == 4.0);
assert(arr[1] == 5.0);
}
return true;
}
int main(int, char**)
{
tests();
static_assert(tests(), "");
return 0;
}
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