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 20 template <typename T> 21 class reference_wrapper { 22 public: 23 using type = T; 24 25 // This constructor is incomplete / incorrect! reference_wrapper(T & reference)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 get()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