std::remove_extent

 

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Template:ddcl list begin <tr class="t-dsc-header">

<td>

Defined in header <type_traits>

</td>

<td></td> <td></td> </tr> <tr class="t-dcl ">

<td >

template< class T >
struct remove_extent;

</td>

<td class="t-dcl-nopad"> </td> <td > (since C++11) </td> </tr> Template:ddcl list end

If T is an array of some type X, provides the member typedef type equal to X, otherwise type is T. Note that if T is a multidimensional array, only the first dimension is removed.

Member types

Name	Definition
type	the type of the element of T

Example

Run this code

#include <iostream>
#include <iterator>
#include <algorithm>
#include <type_traits>
 
template<class A>
typename std::enable_if< std::rank<A>::value == 1 >::type
print_1d(const A& a)
{
    copy(a, a+std::extent<A>::value,
         std::ostream_iterator<typename std::remove_extent<A>::type>(std::cout, " "));
    std::cout << '\n';
}
 
int main()
{
    int a[][3] = {{1,2,3},{4,5,6}};
//  print_1d(a); // compile-time error
    print_1d(a[1]);
}

Output:

4 5 6

See also

is_array (C++11)	checks if a type is an array type (class template)
rank (C++11)	obtains the number of dimensions of an array type (class template)
extent (C++11)	obtains the size of an array type along a specified dimension (class template)
remove_all_extents (C++11)	removes all extents from the given array type (class template)