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std::get(std::array)

template< size_t I, class T, size_t N >
constexpr T& get( array<T,N>& a ) noexcept;
(1) (since C++11)
template< size_t I, class T, size_t N >
constexpr T&& get( array<T,N>&& a ) noexcept;
(2) (since C++11)
template< size_t I, class T, size_t N >
constexpr const T& get( const array<T,N>& a ) noexcept;
(3) (since C++11)
template< size_t I, class T, size_t N >
constexpr const T&& get( const array<T,N>&& a ) noexcept;
(4) (since C++17)

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

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

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