1// Copyright 2023 The Pigweed Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License"); you may not
4// use this file except in compliance with the License. You may obtain a copy of
5// the License at
6//
7//     https://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
11// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
12// License for the specific language governing permissions and limitations under
13// the License.
14#pragma once
15
16#include "pw_polyfill/standard_library/namespace.h"
17
18_PW_POLYFILL_BEGIN_NAMESPACE_STD
19
20template <typename T>
21class reference_wrapper {
22 public:
23  using type = T;
24
25  // This constructor is incomplete / incorrect!
26  constexpr reference_wrapper(T& reference) : pointer_(&reference) {}
27
28  constexpr reference_wrapper(const reference_wrapper&) noexcept = default;
29  constexpr reference_wrapper& operator=(const reference_wrapper&) noexcept =
30      default;
31
32  constexpr T& get() const noexcept { return *pointer_; }
33  constexpr operator T&() const noexcept { return *pointer_; }
34
35 private:
36  T* pointer_;
37};
38
39_PW_POLYFILL_END_NAMESPACE_STD
40