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+/* -*- 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/. */
+
+/* A compile-time constant-length array with bounds-checking assertions. */
+
+#ifndef mozilla_Array_h
+#define mozilla_Array_h
+
+#include "mozilla/Assertions.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/Move.h"
+#include "mozilla/ReverseIterator.h"
+
+#include <stddef.h>
+
+namespace mozilla {
+
+template<typename T, size_t Length>
+class Array
+{
+ T mArr[Length];
+
+public:
+ Array() {}
+
+ template <typename... Args>
+ MOZ_IMPLICIT Array(Args&&... aArgs)
+ : mArr{mozilla::Forward<Args>(aArgs)...}
+ {
+ static_assert(sizeof...(aArgs) == Length,
+ "The number of arguments should be equal to the template parameter Length");
+ }
+
+ T& operator[](size_t aIndex)
+ {
+ MOZ_ASSERT(aIndex < Length);
+ return mArr[aIndex];
+ }
+
+ const T& operator[](size_t aIndex) const
+ {
+ MOZ_ASSERT(aIndex < Length);
+ return mArr[aIndex];
+ }
+
+ typedef T* iterator;
+ typedef const T* const_iterator;
+ typedef ReverseIterator<T*> reverse_iterator;
+ typedef ReverseIterator<const T*> const_reverse_iterator;
+
+ // Methods for range-based for loops.
+ iterator begin() { return mArr; }
+ const_iterator begin() const { return mArr; }
+ const_iterator cbegin() const { return begin(); }
+ iterator end() { return mArr + Length; }
+ const_iterator end() const { return mArr + Length; }
+ const_iterator cend() const { return end(); }
+
+ // Methods for reverse iterating.
+ reverse_iterator rbegin() { return reverse_iterator(end()); }
+ const_reverse_iterator rbegin() const { return const_reverse_iterator(end()); }
+ const_reverse_iterator crbegin() const { return rbegin(); }
+ reverse_iterator rend() { return reverse_iterator(begin()); }
+ const_reverse_iterator rend() const { return const_reverse_iterator(begin()); }
+ const_reverse_iterator crend() const { return rend(); }
+};
+
+template<typename T>
+class Array<T, 0>
+{
+public:
+ T& operator[](size_t aIndex)
+ {
+ MOZ_CRASH("indexing into zero-length array");
+ }
+
+ const T& operator[](size_t aIndex) const
+ {
+ MOZ_CRASH("indexing into zero-length array");
+ }
+};
+
+} /* namespace mozilla */
+
+#endif /* mozilla_Array_h */