RangedArray.h (2285B)
1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */ 3 /* This Source Code Form is subject to the terms of the Mozilla Public 4 * License, v. 2.0. If a copy of the MPL was not distributed with this 5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 6 7 /* 8 * A compile-time constant-length array, with bounds-checking assertions -- but 9 * unlike mozilla::Array, with indexes biased by a constant. 10 * 11 * Thus where mozilla::Array<int, 3> is a three-element array indexed by [0, 3), 12 * mozilla::RangedArray<int, 8, 3> is a three-element array indexed by [8, 11). 13 */ 14 15 #ifndef mozilla_RangedArray_h 16 #define mozilla_RangedArray_h 17 18 #include "mozilla/Array.h" 19 20 namespace mozilla { 21 22 template <typename T, size_t MinIndex, size_t Length> 23 class RangedArray { 24 private: 25 typedef Array<T, Length> ArrayType; 26 ArrayType mArr; 27 28 public: 29 static size_t length() { return Length; } 30 static size_t minIndex() { return MinIndex; } 31 32 T& operator[](size_t aIndex) { 33 MOZ_ASSERT(aIndex >= MinIndex); 34 return mArr[aIndex - MinIndex]; 35 } 36 37 const T& operator[](size_t aIndex) const { 38 MOZ_ASSERT(aIndex >= MinIndex); 39 return mArr[aIndex - MinIndex]; 40 } 41 42 typedef typename ArrayType::iterator iterator; 43 typedef typename ArrayType::const_iterator const_iterator; 44 typedef typename ArrayType::reverse_iterator reverse_iterator; 45 typedef typename ArrayType::const_reverse_iterator const_reverse_iterator; 46 47 // Methods for range-based for loops. 48 iterator begin() { return mArr.begin(); } 49 const_iterator begin() const { return mArr.begin(); } 50 const_iterator cbegin() const { return mArr.cbegin(); } 51 iterator end() { return mArr.end(); } 52 const_iterator end() const { return mArr.end(); } 53 const_iterator cend() const { return mArr.cend(); } 54 55 // Methods for reverse iterating. 56 reverse_iterator rbegin() { return mArr.rbegin(); } 57 const_reverse_iterator rbegin() const { return mArr.rbegin(); } 58 const_reverse_iterator crbegin() const { return mArr.crbegin(); } 59 reverse_iterator rend() { return mArr.rend(); } 60 const_reverse_iterator rend() const { return mArr.rend(); } 61 const_reverse_iterator crend() const { return mArr.crend(); } 62 }; 63 64 } // namespace mozilla 65 66 #endif // mozilla_RangedArray_h