std::get(std::array) (3) Linux Manual Page

std::get(std::array) – std::get(std::array)

Synopsis

template <size_t I, class T, size_t N>
(1)(since C++ 11)

    constexpr T &get(array<T, N> &a) noexcept;

template <size_t I, class T, size_t N>
(2)(since C++ 11)

    constexpr T &&get(array<T, N> &&a) noexcept;

template <size_t I, class T, size_t N>
(3)(since C++ 11)

    constexpr const T &get(const array<T, N> &a) noexcept;

template <size_t I, class T, size_t N>
(4)(since C++ 17)

    constexpr const T &&get(const 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.

Notes

The overloads are marked as constexpr since C++14.

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)

See also

                       access specified element
operator[] (public member function)
                       access specified element with bounds checking
at (public member function)
                       tuple accesses specified element
std::get(std::tuple) (function template)
std::get(std::pair) accesses an element of a pair
                       (function template)
(C++11)
std::get(std::variant) reads the value of the variant given the index or the type (if the type is unique), throws on error
                       (function template)
(C++17)