tuple_element 클래스 <utility>
Wraps the type of a pair element.
template<class T1, class T2>
class tuple_element<0, pair<T1, T2> > {
typedef T1 type;
};
template<class T1, class T2>
class tuple_element<1, pair<T1, T2> > {
typedef T2 type;
};
매개 변수
T1
The type of the first pair elemment.T2
The type of the second pair elemment.
설명
The templates are specializations of the template class tuple_element 클래스 <tuple>. Each has a nested typedef type that is a synonym for the type of the corresponding pair element.
예제
// std_tr1__utility__tuple_element.cpp
// compile with: /EHsc
#include <utility>
#include <iostream>
typedef std::pair<int, double> Mypair;
int main()
{
Mypair c0(0, 1);
// display contents " 0 1"
std::cout << " " << std::get<0>(c0);
std::cout << " " << std::get<1>(c0);
std::cout << std::endl;
// display first element " 0"
std::tuple_element<0, Mypair>::type val = std::get<0>(c0);
std::cout << " " << val;
std::cout << std::endl;
return (0);
}
요구 사항
Header: <utility>
네임스페이스: std