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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
//
//===----------------------------------------------------------------------===//
// <functional>
//
// template <class T>
// struct unwrap_reference;
//
// template <class T>
// using unwrap_reference_t = typename unwrap_reference<T>::type;
// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
#include <functional>
#include <type_traits>
template <typename T, typename Expected>
void check_equal() {
static_assert(std::is_same_v<typename std::unwrap_reference<T>::type, Expected>);
static_assert(std::is_same_v<typename std::unwrap_reference<T>::type, std::unwrap_reference_t<T>>);
}
template <typename T>
void check() {
check_equal<T, T>();
check_equal<T&, T&>();
check_equal<T const, T const>();
check_equal<T const&, T const&>();
check_equal<std::reference_wrapper<T>, T&>();
check_equal<std::reference_wrapper<T const>, T const&>();
}
struct T { };
int main(int, char**) {
check<T>();
check<int>();
check<float>();
check<T*>();
check<int*>();
check<float*>();
return 0;
}
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