extent Class

Gets an array dimension.

template<class Ty, unsigned I = 0>
    struct extent;


The type to query.


The array bound to query.

If Ty is an array type that has at least I dimensions, the type query holds the number of elements in the dimension specified by I. If Ty is not an array type or its rank is less than I, or if I is zero and Ty is of type "array of unknown bound of U", the type query holds the value 0.


// std_tr1__type_traits__extent.cpp 
// compile with: /EHsc 
#include <type_traits> 
#include <iostream> 
int main() 
    std::cout << "extent 0 == " 
        << std::extent<int[5][10]>::value << std::endl; 
    std::cout << "extent 1 == " 
        << std::extent<int[5][10], 1>::value << std::endl; 
    return (0); 
extent 0 == 5
extent 1 == 10

Header: <type_traits>

Namespace: std