1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // Slightly adapted for inclusion in V8. 6 // Copyright 2014 the V8 project authors. All rights reserved. 7 8 #ifndef V8_BASE_ADAPTERS_H_ 9 #define V8_BASE_ADAPTERS_H_ 10 11 #include "src/base/macros.h" 12 13 namespace v8 { 14 namespace base { 15 16 // Internal adapter class for implementing base::Reversed. 17 template <typename T> 18 class ReversedAdapter { 19 public: 20 typedef decltype(static_cast<T*>(nullptr)->rbegin()) Iterator; 21 ReversedAdapter(T & t)22 explicit ReversedAdapter(T& t) : t_(t) {} ReversedAdapter(const ReversedAdapter & ra)23 ReversedAdapter(const ReversedAdapter& ra) : t_(ra.t_) {} 24 begin()25 Iterator begin() const { return t_.rbegin(); } end()26 Iterator end() const { return t_.rend(); } 27 28 private: 29 T& t_; 30 31 DISALLOW_ASSIGN(ReversedAdapter); 32 }; 33 34 // Reversed returns a container adapter usable in a range-based "for" statement 35 // for iterating a reversible container in reverse order. 36 // 37 // Example: 38 // 39 // std::vector<int> v = ...; 40 // for (int i : base::Reversed(v)) { 41 // // iterates through v from back to front 42 // } 43 template <typename T> Reversed(T & t)44ReversedAdapter<T> Reversed(T& t) { 45 return ReversedAdapter<T>(t); 46 } 47 48 } // namespace base 49 } // namespace v8 50 51 #endif // V8_BASE_ADAPTERS_H_ 52