std::extents<IndexType,Extents...>::extent

 

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constexpr index_type extent( rank_type i ) const noexcept;		(since C++23)

Returns dynamic extent size of an extents at a certain rank index.

Parameters

i

-

The rank index to get the extent size of

Return value

The dynamic extent size of an extents at a certain rank index.

Example

Run this code

#include <iostream>
#include <mdspan>
 
int main()
{
    std::extents<int, 1, 2> e1;
    std::extents<int, 3, std::dynamic_extent, std::dynamic_extent> e2(4, 5);
    std::cout << e1.extent(0) << ", " << e1.extent(1) << '\n';
    std::cout << e2.extent(0) << ", " << e2.extent(1) << ", " << e2.extent(2) << '\n';
}

Output:

1, 2
3, 4, 5

See also

static_extent [static]	returns static extent size of an extents at a certain rank index (public static member function)
extent (C++11)	obtains the size of an array type along a specified dimension (class template)