text: //===----------------------------------------------------------------------===//
  //
  // 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++03, c++11, c++14, c++17
  
  #include <functional>
  #include <type_traits>
  
  #include "test_macros.h"
  
  
  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;
  }
  