/* -*- 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"
#include "mozilla/Likely.h"
namespace mozilla {
template <
typename T, size_t _Length>
class Array {
T mArr[_Length];
public:
using ElementType = T;
static constexpr size_t Length = _Length;
constexpr 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");
}
constexpr T&
operator[](size_t aIndex) {
if (MOZ_UNLIKELY(aIndex >= Length)) {
detail::InvalidArrayIndex_CRASH(aIndex, Length);
}
return mArr[aIndex];
}
constexpr
const T&
operator[](size_t aIndex)
const {
if (MOZ_UNLIKELY(aIndex >= Length)) {
detail::InvalidArrayIndex_CRASH(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(); }
// Method for std::size.
constexpr size_t size()
const {
return Length; }
// 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 */
