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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 <stddef.h>
#include <iterator>
#include <ostream>
#include <utility>
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
namespace mozilla {
template <typename T, size_t _Length>
class Array {
T mArr[_Length];
public:
using ElementType = T;
static constexpr size_t Length = _Length;
Array() = default;
template <typename... Args>
MOZ_IMPLICIT constexpr Array(Args&&... aArgs)
: mArr{std::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];
}
bool operator==(const Array<T, Length>& aOther) const {
for (size_t i = 0; i < Length; i++) {
if (mArr[i] != aOther[i]) {
return false;
}
}
return true;
}
typedef T* iterator;
typedef const T* const_iterator;
typedef std::reverse_iterator<T*> reverse_iterator;
typedef std::reverse_iterator<const T*> const_reverse_iterator;
// Methods for range-based for loops.
iterator begin() { return mArr; }
constexpr const_iterator begin() const { return mArr; }
constexpr const_iterator cbegin() const { return begin(); }
iterator end() { return mArr + Length; }
constexpr const_iterator end() const { return mArr + Length; }
constexpr 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");
}
};
// MOZ_DBG support
template <typename T, size_t Length>
std::ostream& operator<<(std::ostream& aOut, const Array<T, Length>& aArray) {
return aOut << Span(aArray);
}
} /* namespace mozilla */
#endif /* mozilla_Array_h */