tuple_size Class <utility>
Wraps pair element count.
template<class T1, class T2>
class tuple_size<pair<T1, T2> > {
static const unsigned value = 2;
};
Parameters
T1
The type of the first pair elemment.T2
The type of the second pair elemment.
Remarks
The template is a specialization of the template class tuple_size Class <tuple>. It has a member value that is an integral constant expression whose value is 2.
Example
// std_tr1__utility__tuple_size.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 size " 2"
std::cout << " " << std::tuple_size<Mypair>::value;
std::cout << std::endl;
return (0);
}
0 1 2
Requirements
Header: <utility>
Namespace: std