std::get(std::pair)
From cppreference.com
(1) | ||
template< size_t N, class T1, class T2 >
typename std::tuple_element<I, std::pair<T1,T2> >::type& |
(1) | (since C++11) (until C++14) |
template< size_t N, class T1, class T2 >
constexpr std::tuple_element_t<I, std::pair<T1,T2> >& |
(1) | (since C++14) |
(2) | ||
template< size_t N, class T1, class T2 >
const typename std::tuple_element<I, std::pair<T1,T2> >::type& |
(2) | (since C++11) (until C++14) |
template< size_t N, class T1, class T2 >
constexpr const std::tuple_element_t<I, std::pair<T1,T2> >& |
(2) | (since C++14) |
(3) | ||
(3) | (since C++11) (until C++14) |
|
(3) | (since C++14) | |
(4) | (since C++14) | |
template <class T, class U>
constexpr T&& get(std::pair<T, U>&& p); |
(5) | (since C++14) |
(6) | (since C++14) | |
template <class T, class U>
constexpr T&& get(std::pair<U, T>&& p); |
(7) | (since C++14) |
Extracts an element from the pair using tuple-like interface.
Type-based overloads 4-7 fail to compile if the types T
and U
are the same.
Contents |
[edit] Parameters
p | - | pair whose contents to extract |
[edit] Return value
1,2) Returns
p.first
if N==0
and p.second
if N==1
.
4) Returns std::get<0>(p)
5) Returns std::get<0>(std::move(p))
6) Returns std::get<1>(p)
7) Returns std::get<1>(std::move(p))
[edit] Exceptions
noexcept specification:
noexcept
[edit] Example
Run this code
#include <iostream> #include <utility> int main() { auto p = std::make_pair(1, 3.14); std::cout << '(' << std::get<0>(p) << ", " << std::get<1>(p) << ")\n"; std::cout << '(' << std::get<int>(p) << ", " << std::get<double>(p) << ")\n"; }
Output:
(1, 3.14) (1, 3.14)
[edit] See also
tuple accesses specified element (function template) |
|
accesses an element of an array (function template) |