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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, c++11, c++14
// <utility>
// struct in_place_t {
// explicit in_place_t() = default;
// };
// inline constexpr in_place_t in_place{};
// template <class T>
// struct in_place_type_t {
// explicit in_place_type_t() = default;
// };
// template <class T>
// inline constexpr in_place_type_t<T> in_place_type{};
// template <size_t I>
// struct in_place_index_t {
// explicit in_place_index_t() = default;
// };
// template <size_t I>
// inline constexpr in_place_index_t<I> in_place_index{};
#include <cassert>
#include <memory>
#include <type_traits>
#include <utility>
template <class Tp, class Up>
constexpr bool check_tag(Up) {
return std::is_same<Tp, std::decay_t<Tp>>::value
&& std::is_same<Tp, Up>::value;
}
int main(int, char**) {
// test in_place_t
{
using T = std::in_place_t;
static_assert(check_tag<T>(std::in_place));
}
// test in_place_type_t
{
using T1 = std::in_place_type_t<void>;
using T2 = std::in_place_type_t<int>;
using T3 = std::in_place_type_t<const int>;
static_assert(!std::is_same<T1, T2>::value && !std::is_same<T1, T3>::value);
static_assert(!std::is_same<T2, T3>::value);
static_assert(check_tag<T1>(std::in_place_type<void>));
static_assert(check_tag<T2>(std::in_place_type<int>));
static_assert(check_tag<T3>(std::in_place_type<const int>));
}
// test in_place_index_t
{
using T1 = std::in_place_index_t<0>;
using T2 = std::in_place_index_t<1>;
using T3 = std::in_place_index_t<static_cast<std::size_t>(-1)>;
static_assert(!std::is_same<T1, T2>::value && !std::is_same<T1, T3>::value);
static_assert(!std::is_same<T2, T3>::value);
static_assert(check_tag<T1>(std::in_place_index<0>));
static_assert(check_tag<T2>(std::in_place_index<1>));
static_assert(check_tag<T3>(std::in_place_index<static_cast<std::size_t>(-1)>));
}
return 0;
}
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