std::get(std::array)
From cppreference.com
| Defined in header <array>
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||
template< std::size_t I, class T, std::size_t N >
T& get( std::array<T,N>& a ) noexcept;
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(1) | (since C++11) (constexpr since C++14) |
template< std::size_t I, class T, std::size_t N >
T&& get( std::array<T,N>&& a ) noexcept;
|
(2) | (since C++11) (constexpr since C++14) |
template< std::size_t I, class T, std::size_t N >
const T& get( const std::array<T,N>& a ) noexcept;
|
(3) | (since C++11) (constexpr since C++14) |
template< std::size_t I, class T, std::size_t N >
const T&& get( const std::array<T,N>&& a ) noexcept;
|
(4) | (since C++11) (constexpr since C++14) |
Extracts the Ith element from the array using tuple-like interface.
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 <array>
#include <iostream>
constexpr std::array v{1, 2, 3};
static_assert(get<0>(v) == 1 && get<1>(v) == 2 && get<2>(v) == 3);
int main()
{
std::array<int, 3> a;
// set values:
get<0>(a) = 1, get<1>(a) = 2, get<2>(a) = 3;
// get values:
std::cout << '(' << get<0>(a) << ',' << get<1>(a) << ',' << get<2>(a) << ")\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 |