NAME¶

std::get(std::array) - std::get(std::array)

Synopsis¶

Defined in header <array>
template< std::size_t I, class T, (since
std::size_t N > C++11)
T& get( std::array<T,N>& a ) noexcept; (until
C++14)
template< std::size_t I, class T,
std::size_t N > (since
constexpr T& get( std::array<T,N>& a ) C++14)
noexcept;
template< std::size_t I, class T, (since
std::size_t N > C++11)
T&& get( std::array<T,N>&& a ) noexcept; (until
C++14)
template< std::size_t I, class T,
std::size_t N > (since
constexpr T&& get( std::array<T,N>&& a ) C++14)
noexcept; (1)
template< std::size_t I, class T, (since
std::size_t N > C++11)
const T& get( const std::array<T,N>& a ) (until
noexcept; (2) C++14)
template< std::size_t I, class T,
std::size_t N > (since
constexpr const T& get( const C++14)
std::array<T,N>& a ) noexcept; (3)
template< std::size_t I, class T, (since
std::size_t N > C++11)
const T&& get( const std::array<T,N>&& a ) (until
noexcept; (4) C++14)
template< std::size_t I, class T,
std::size_t N > (since
constexpr const T&& get( const C++14)
std::array<T,N>&& a ) noexcept;

Extracts the Ith element element from the array.

I must be an integer value in range [0, N). This is enforced at compile time as
opposed to at() or operator[].

Parameters¶

a - array whose contents to extract

Return value¶

A reference to the Ith element of a.

Complexity¶

Constant.

Example¶

// Run this code

#include <iostream>
#include <array>

int main()
{
std::array<int, 3> arr;

// set values:
std::get<0>(arr) = 1;
std::get<1>(arr) = 2;
std::get<2>(arr) = 3;

// get values:
std::cout << "(" << std::get<0>(arr) << ", " << std::get<1>(arr)
<< ", " << std::get<2>(arr) << ")\n";
}

Output:¶

(1, 2, 3)

Defect reports

The following behavior-changing defect reports were applied retroactively to
previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 2485 C++11 there are no overloads for const array&& the overloads are added

See also¶

Structured binding (C++17) binds the specified names to sub-objects or tuple
elements of the initializer
operator[] access specified element
(C++11) (public member function)
at access specified element with bounds checking
(C++11) (public member function)
std::get(std::tuple) tuple accesses specified element
(C++11) (function template)
std::get(std::pair) accesses an element of a pair
(C++11) (function template)
std::get(std::variant) reads the value of the variant given the index or the
(C++17) type (if the type is unique), throws on error
(function template)
get(std::ranges::subrange) obtains iterator or sentinel from a std::ranges::subrange
(C++20) (function template)