/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set ts=8 sts=2 et sw=2 tw=80: */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ /* EnumeratedArray is like Array, but indexed by a typed enum. */ #ifndef mozilla_EnumeratedArray_h #define mozilla_EnumeratedArray_h #include "mozilla/Array.h" #include "mozilla/Move.h" namespace mozilla { /** * EnumeratedArray is a fixed-size array container for use when an * array is indexed by a specific enum class. * * This provides type safety by guarding at compile time against accidentally * indexing such arrays with unrelated values. This also removes the need * for manual casting when using a typed enum value to index arrays. * * Aside from the typing of indices, EnumeratedArray is similar to Array. * * Example: * * enum class AnimalSpecies { * Cow, * Sheep, * Count * }; * * EnumeratedArray<AnimalSpecies, AnimalSpecies::Count, int> headCount; * * headCount[AnimalSpecies::Cow] = 17; * headCount[AnimalSpecies::Sheep] = 30; * */ template<typename IndexType, IndexType SizeAsEnumValue, typename ValueType> class EnumeratedArray { public: static const size_t kSize = size_t(SizeAsEnumValue); private: typedef Array<ValueType, kSize> ArrayType; ArrayType mArray; public: EnumeratedArray() {} template <typename... Args> MOZ_IMPLICIT EnumeratedArray(Args&&... aArgs) : mArray{mozilla::Forward<Args>(aArgs)...} {} explicit EnumeratedArray(const EnumeratedArray& aOther) { for (size_t i = 0; i < kSize; i++) { mArray[i] = aOther.mArray[i]; } } EnumeratedArray(EnumeratedArray&& aOther) { for (size_t i = 0; i < kSize; i++) { mArray[i] = Move(aOther.mArray[i]); } } ValueType& operator[](IndexType aIndex) { return mArray[size_t(aIndex)]; } const ValueType& operator[](IndexType aIndex) const { return mArray[size_t(aIndex)]; } typedef typename ArrayType::iterator iterator; typedef typename ArrayType::const_iterator const_iterator; typedef typename ArrayType::reverse_iterator reverse_iterator; typedef typename ArrayType::const_reverse_iterator const_reverse_iterator; // Methods for range-based for loops. iterator begin() { return mArray.begin(); } const_iterator begin() const { return mArray.begin(); } const_iterator cbegin() const { return mArray.cbegin(); } iterator end() { return mArray.end(); } const_iterator end() const { return mArray.end(); } const_iterator cend() const { return mArray.cend(); } // Methods for reverse iterating. reverse_iterator rbegin() { return mArray.rbegin(); } const_reverse_iterator rbegin() const { return mArray.rbegin(); } const_reverse_iterator crbegin() const { return mArray.crbegin(); } reverse_iterator rend() { return mArray.rend(); } const_reverse_iterator rend() const { return mArray.rend(); } const_reverse_iterator crend() const { return mArray.crend(); } }; } // namespace mozilla #endif // mozilla_EnumeratedArray_h