<array>
functions
The <array> header includes two non-member functions, get
and swap
, that operate on array objects.
get
Returns a reference to the specified element of the array.
template <int Index, class T, size_t N>
constexpr T& get(array<T, N>& arr) noexcept;
template <int Index, class T, size_t N>
constexpr const T& get(const array<T, N>& arr) noexcept;
template <int Index, class T, size_t N>
constexpr T&& get(array<T, N>&& arr) noexcept;
Parameters
Index
The element offset.
T
The type of an element.
N
The number of elements in the array.
arr
The array to select from.
Example
#include <array>
#include <iostream>
using namespace std;
typedef array<int, 4> MyArray;
int main()
{
MyArray c0 { 0, 1, 2, 3 };
// display contents " 0 1 2 3"
for (const auto& e : c0)
{
cout << " " << e;
}
cout << endl;
// display odd elements " 1 3"
cout << " " << get<1>(c0);
cout << " " << get<3>(c0) << endl;
}
0 1 2 3
1 3
swap
A non-member template specialization of std::swap
that swaps two array objects.
template <class Ty, std::size_t N>
void swap(array<Ty, N>& left, array<Ty, N>& right);
Parameters
Ty
The type of an element.
N
The size of the array.
left
The first array to swap.
right
The second array to swap.
Remarks
The template function executes left.swap(right)
.
Example
// std__array__swap.cpp
// compile with: /EHsc
#include <array>
#include <iostream>
typedef std::array<int, 4> Myarray;
int main()
{
Myarray c0 = { 0, 1, 2, 3 };
// display contents " 0 1 2 3"
for (Myarray::const_iterator it = c0.begin();
it != c0.end(); ++it)
std::cout << " " << *it;
std::cout << std::endl;
Myarray c1 = { 4, 5, 6, 7 };
c0.swap(c1);
// display swapped contents " 4 5 6 7"
for (Myarray::const_iterator it = c0.begin();
it != c0.end(); ++it)
std::cout << " " << *it;
std::cout << std::endl;
swap(c0, c1);
// display swapped contents " 0 1 2 3"
for (Myarray::const_iterator it = c0.begin();
it != c0.end(); ++it)
std::cout << " " << *it;
std::cout << std::endl;
return (0);
}
0 1 2 3
4 5 6 7
0 1 2 3