tuple_size Class <tuple>
Wraps tuple element count.
template<class Tuple>
class tuple_size {
static const unsigned value = ...;
};
Parameters
- Tuple
The type of the tuple.
Remarks
The template class has a member value that is an integral constant expression whose value is the extent of the tuple type Tuple.
Example
// std_tr1__tuple__tuple_size.cpp
// compile with: /EHsc
#include <tuple>
#include <iostream>
#include <utility>
typedef std::tuple<int, double, int, double> Mytuple;
int main()
{
Mytuple c0(0, 1, 2, 3);
// display contents " 0 1 2 3"
std::cout << " " << std::get<0>(c0);
std::cout << " " << std::get<1>(c0);
std::cout << " " << std::get<2>(c0);
std::cout << " " << std::get<3>(c0);
std::cout << std::endl;
// display size " 4"
std::cout << " " << std::tuple_size<Mytuple>::value;
std::cout << std::endl;
return (0);
}
0 1 2 3 4
Requirements
Header: <tuple>
Namespace: std