Standard library header <array> (C++11)

 

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Standard library headers

Language support
<cstddef> <cstdlib> <version> (C++20) <limits> <climits>	<cfloat> <cstdint> (C++11) <stdfloat> (C++23) <new> <typeinfo>	<source_location> (C++20) <exception> <initializer_list> (C++11) <compare> (C++20)	<coroutine> (C++20) <csignal> <csetjmp> <cstdarg>
Concepts
<concepts> (C++20)
Diagnostics
<stdexcept> <stacktrace> (C++23)	<cassert>	<cerrno>	<system_error> (C++11)
Memory management
<memory>	<memory_resource> (C++17)	<scoped_allocator> (C++11)
Metaprogramming
<type_traits> (C++11)	<ratio> (C++11)
General utilities
<utility> <tuple> (C++11) <optional> (C++17) <variant> (C++17)	<any> (C++17) <expected> (C++23) <bitset>	<functional> <typeindex> (C++11) <execution> (C++17)	<charconv> (C++17) <format> (C++20) <bit> (C++20)
Strings
<string_view> (C++17) <string>	<cctype> <cwctype>	<cstring> <cwchar>	<cuchar> (C++11)
Containers
<array> (C++11) <deque> <forward_list> (C++11) <list>	<vector> <map> <set> <unordered_map> (C++11)	<unordered_set> (C++11) <queue> <stack> <flat_map> (C++23)	<flat_set> (C++23) <span> (C++20) <mdspan> (C++23)
Iterators
<iterator>
Ranges
<ranges> (C++20)	<generator> (C++23)
Algorithms
<algorithm>	<numeric>
Numerics
<cfenv> (C++11) <complex>	<random> (C++11) <valarray>	<cmath>	<numbers> (C++20)
Time
<chrono> (C++11)	<ctime>
Localization
<locale>	<clocale>	<codecvt> (C++11/17*)
Input/output
<iosfwd> <iostream> <ios> <streambuf>	<istream> <ostream> <iomanip> <print> (C++23)	<sstream> <spanstream> (C++23) <fstream> <syncstream> (C++20)	<filesystem> (C++17) <cstdio> <cinttypes> (C++11) <strstream> (C++98*)
Regular expressions
<regex> (C++11)
Concurrency support
<stop_token> (C++20) <thread> (C++11) <atomic> (C++11)	<stdatomic.h> (C++23) <mutex> (C++11) <shared_mutex> (C++14)	<condition_variable> (C++11)   <semaphore> (C++20) <latch> (C++20)	<barrier> (C++20) <future> (C++11)
C compatibility
<cstdbool> (C++11/17/20*)   <ccomplex> (C++11/17/20*)	<ctgmath> (C++11/17/20*)	<cstdalign> (C++11/17/20*)	<ciso646> (until C++20)

 

This header is part of the containers library.

Includes
<compare> (C++20)	Three-way comparison operator support
<initializer_list> (C++11)	std::initializer_list class template
Classes
array (C++11)	static contiguous array (class template)
tuple_size (C++11)	obtains the number of elements of a tuple-like type (class template)
tuple_element (C++11)	obtains the element types of a tuple-like type (class template)
std::tuple_size<std::array> (C++11)	obtains the size of an array (class template specialization)
std::tuple_element<std::array> (C++11)	obtains the type of the elements of array (class template specialization)
Functions
operator==operator!=operator<operator<=operator>operator>=operator<=> (removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(C++20)	lexicographically compares the values in the array (function template)
std::swap(std::array) (C++11)	specializes the std::swap algorithm (function template)
to_array (C++20)	creates a std::array object from a built-in array (function template)
std::get(std::array) (C++11)	accesses an element of an array (function template)
Range access
begincbegin (C++11)(C++14)	returns an iterator to the beginning of a container or array (function template)
endcend (C++11)(C++14)	returns an iterator to the end of a container or array (function template)
rbegincrbegin (C++14)	returns a reverse iterator to the beginning of a container or array (function template)
rendcrend (C++14)	returns a reverse end iterator for a container or array (function template)
sizessize (C++17)(C++20)	returns the size of a container or array (function template)
empty (C++17)	checks whether the container is empty (function template)
data (C++17)	obtains the pointer to the underlying array (function template)

Synopsis

#include <compare>
#include <initializer_list>
 
namespace std
{
    // class template array
    template<class T, size_t N> struct array;
 
    template<class T, size_t N>
        constexpr bool operator==(const array<T, N>& x, const array<T, N>& y);
    template<class T, size_t N>
        constexpr __synth_three_way_result<T>
            operator<=>(const array<T, N>& x, const array<T, N>& y);
 
    // specialized algorithms
    template<class T, size_t N>
        constexpr void swap(array<T, N>& x, array<T, N>& y) noexcept(noexcept(x.swap(y)));
 
    // array creation functions
    template<class T, size_t N>
        constexpr array<remove_cv_t<T>, N> to_array(T (&a)[N]);
    template<class T, size_t N>
        constexpr array<remove_cv_t<T>, N> to_array(T (&&a)[N]);
 
    // tuple interface
    template<class T> struct tuple_size;
    template<size_t I, class T> struct tuple_element;
    template<class T, size_t N>
        struct tuple_size<array<T, N>>;
    template<size_t I, class T, size_t N>
        struct tuple_element<I, array<T, N>>;
    template<size_t I, class T, size_t N>
        constexpr T& get(array<T, N>&) noexcept;
    template<size_t I, class T, size_t N>
        constexpr T&& get(array<T, N>&&) noexcept;
    template<size_t I, class T, size_t N>
        constexpr const T& get(const array<T, N>&) noexcept;
    template<size_t I, class T, size_t N>
        constexpr const T&& get(const array<T, N>&&) noexcept;
}

Class template std::array

namespace std
{
    template<class T, size_t N>
    struct array
    {
        // types
        using value_type             = T;
        using pointer                = T*;
        using const_pointer          = const T*;
        using reference              = T&;
        using const_reference        = const T&;
        using size_type              = size_t;
        using difference_type        = ptrdiff_t;
        using iterator               = /* implementation-defined */;
        using const_iterator         = /* implementation-defined */;
        using reverse_iterator       = std::reverse_iterator<iterator>;
        using const_reverse_iterator = std::reverse_iterator<const_iterator>;
 
        // no explicit construct/copy/destroy for aggregate type
 
        constexpr void fill(const T& u);
        constexpr void swap(array&) noexcept(is_nothrow_swappable_v<T>);
 
        // iterators
        constexpr iterator               begin() noexcept;
        constexpr const_iterator         begin() const noexcept;
        constexpr iterator               end() noexcept;
        constexpr const_iterator         end() const noexcept;
 
        constexpr reverse_iterator       rbegin() noexcept;
        constexpr const_reverse_iterator rbegin() const noexcept;
        constexpr reverse_iterator       rend() noexcept;
        constexpr const_reverse_iterator rend() const noexcept;
 
        constexpr const_iterator         cbegin() const noexcept;
        constexpr const_iterator         cend() const noexcept;
        constexpr const_reverse_iterator crbegin() const noexcept;
        constexpr const_reverse_iterator crend() const noexcept;
 
        // capacity
        [[nodiscard]] constexpr bool empty() const noexcept;
        constexpr size_type size() const noexcept;
        constexpr size_type max_size() const noexcept;
 
        // element access
        constexpr reference       operator[](size_type n);
        constexpr const_reference operator[](size_type n) const;
        constexpr reference       at(size_type n);
        constexpr const_reference at(size_type n) const;
        constexpr reference       front();
        constexpr const_reference front() const;
        constexpr reference       back();
        constexpr const_reference back() const;
 
        constexpr T*       data() noexcept;
        constexpr const T* data() const noexcept;
    };
 
    template<class T, class... U>
        array(T, U...) -> array<T, 1 + sizeof...(U)>;
}