function template
<array>
std::get (array)
template <size_t I, class T, size_t N> T& get (array<T,N>& arr) noexcept;
template <size_t I, class T, size_t N> T&& get (array<T,N>&& arr) noexcept;
template <size_t I, class T, size_t N> const T& get (const array<T,N>& arr) noexcept;
Get element (tuple interface)
Returns a reference to the Ith element of array arr.
This overload of tuple's homonym function get is provided so that array objects can be treated as tuples. For that purpose, header <array> also overloads tuple_size and tuple_element types with the appropriate members defined.
Template parameters
- I
- Position of an element in the array, with 0 as the position of the first element.
size_t is an unsigned integral type.
- T
- Type of elements contained in the array (generally obtained implicitly from arr).
- N
- Size of the array, in number of elements (generally obtained implicitly from arr).
Function parameters
- arr
- An array container.
Return value
A reference to the element at the specified position in the array.
Example
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// arrays as tuples
#include <iostream>
#include <array>
#include <tuple>
int main ()
{
std::array<int,3> myarray = {10, 20, 30};
std::tuple<int,int,int> mytuple (10, 20, 30);
std::tuple_element<0,decltype(myarray)>::type myelement; // int myelement
myelement = std::get<2>(myarray);
std::get<2>(myarray) = std::get<0>(myarray);
std::get<0>(myarray) = myelement;
std::cout << "first element in myarray: " << std::get<0>(myarray) << "\n";
std::cout << "first element in mytuple: " << std::get<0>(mytuple) << "\n";
return 0;
}
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Output:
first element in myarray: 30
first element in mytuple: 10
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Iterator validity
No changes.
Data races
Element I of arr is potentially accessed or modified by the caller. Concurrently accessing or modifying other elements of arr is safe.
Exception safety
No-throw guarantee: this function never throws exceptions.