1 /* 2 * Copyright (C) 2020 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #pragma once 17 18 #include <memory> 19 #include <utility> 20 21 namespace android { 22 23 namespace aidl { 24 25 // nullable/make_nullable provide source-level compatibility between std::opional and std::unique_ptr 26 // usage: 27 // nullable<Foo> a; 28 // nullable<Foo> b = make_nullable<Foo>(...); 29 // auto c = make_nullable<Foo>(...); 30 // c.reset(); 31 // c = make_nullable<Foo>(...); 32 // c = std::move(a); 33 34 template <typename T> 35 using nullable = std::unique_ptr<T>; 36 37 template <typename T, typename... Args> make_nullable(Args &&...args)38inline nullable<T> make_nullable(Args&&... args) { 39 return std::make_unique<T>(std::forward<Args>(args)...); 40 } 41 42 } // namespace aidl 43 44 } // namespace android