Standard library header <array>

 

C++

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Utilities library

Strings library

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Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Standard Library header files

Language Support
<cstddef> <limits> <climits>	<cfloat> <cstdint> <new>	<typeinfo> <exception> <initializer_list>	<csignal> <csetjmp> <cstdarg>
Diagnostics
<stdexcept>	<cassert>	<cerrno>	<system_error>
General utilities
<utility> <memory> <memory_resource> <scoped_allocator>	<tuple> <optional> <any> <variant>	<bitset> <functional> <type_traits> <ratio>	<chrono> <ctime> <typeindex> <cstdlib>
Strings
<string> <string_view>	<cctype> <cwctype>	<cwchar> <cuchar>	<cstring>
Localization
<locale>	<codecvt>	<clocale>
Containers
<array> <deque> <vector>	<forward_list> <list>	<map> <set> <queue>	<unordered_map> <unordered_set> <stack>
Iterators
<iterator>
Algorithms
<algorithm>	<execution_policy>
Numerics
<complex> <random>	<valarray> <numeric>	<cfenv> <cmath>
Input/Output
<iosfwd> <iostream> <ios>	<streambuf> <istream> <ostream>	<iomanip> <sstream> <fstream>	<filesystem> <cstdio> <cinttypes>
Regular expressions
<regex>
Thread support
<thread> <atomic>	<mutex> <shared_mutex>	<condition_variable> <future>
C compatibility
<ciso646> <cstdalign>	<cstdbool> <ccomplex>	<ctgmath>

 

This header is part of the containers library.

Includes
<initializer_list>(C++11)
Classes
array (since C++11)	static contiguous array (class template)
std::tuple_size<std::array>	obtains the size of an array (class template specialization)
std::tuple_element<std::array>	obtains the type of the elements of array (class template specialization)
Functions
operator==operator!=operator<operator<=operator>operator>=	lexicographically compares the values in the array (function template)
std::get(std::array)	accesses an element of an array (function template)
std::swap(std::array) (C++11)	specializes the std::swap algorithm (function template)

Synopsis

#include <initializer_list>
 
namespace std {
 
    template <class T, size_t N > struct array;
 
    template <class T, size_t N>
        bool operator==(const array<T,N>& x, const array<T,N>& y);
    template <class T, size_t N>
        bool operator!=(const array<T,N>& x, const array<T,N>& y);
    template <class T, size_t N>
        bool operator<(const array<T,N>& x, const array<T,N>& y);
    template <class T, size_t N>
        bool operator>(const array<T,N>& x, const array<T,N>& y);
    template <class T, size_t N>
        bool operator<=(const array<T,N>& x, const array<T,N>& y);
    template <class T, size_t N>
        bool operator>=(const array<T,N>& x, const array<T,N>& y);
 
    template <class T, size_t N >
        void swap(array<T,N>& x, array<T,N>& y) noexcept(noexcept(x.swap(y)));
 
    template <class T> class tuple_size;
    template <size_t I, class T> class 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> T& get(array<T, N>&) noexcept;
    template <size_t I, class T, size_t N> T&& get(array<T, N>&&) noexcept;
    template <size_t I, class T, size_t N> const T& get(const array<T, N>&) noexcept;
}

Class std::array

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

Note

The variable array::elems is only for exposition, it's not part of the interface.