extent Class
Gets an array dimension.
Syntax
template <class Ty, unsigned I = 0>
struct extent;
Parameters
Ty
The type to query.
I
The array bound to query.
Remarks
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.
Example
// std__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
Requirements
Header: <type_traits>
Namespace: std