Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 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 | |
| 22 | explicit ReversedAdapter(T& t) : t_(t) {} |
| 23 | ReversedAdapter(const ReversedAdapter& ra) : t_(ra.t_) {} |
| 24 | |
| 25 | Iterator begin() const { return t_.rbegin(); } |
| 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> |
| 44 | ReversedAdapter<T> Reversed(T& t) { |
| 45 | return ReversedAdapter<T>(t); |
| 46 | } |
| 47 | |
| 48 | } // namespace base |
| 49 | } // namespace v8 |
| 50 | |
| 51 | #endif // V8_BASE_ADAPTERS_H_ |