C++

Reference

<type_traits>

class template
<type_traits>

std::remove_all_extents

template <class T> struct remove_all_extents;
Remove all array extents
Obtains the type of the elements in the deepest dimension of T (if T is an array type).

The transformed type is aliased as member type remove_all_extents::type.

If T is an array type, this is the same type as the elements in its deepest dimension. Otherwise, member type is the same as T.

Notice that, for multidimensional arrays, all dimensions are removed (see remove_extent to remove a single dimension from an array type).

This class merely obtains a type using another type as model, but it does not transform values or objects between those types.

Template parameters

T
A type.

Member types

member typedefinition
typeIf T is an array, the type of the elements in the deepest dimension of T.
Otherwise, T

Example

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// remove_all_extents
#include <iostream>
#include <type_traits>

int main() {
  typedef std::remove_all_extents<int>::type A;                // int
  typedef std::remove_all_extents<int[24]>::type B;            // int
  typedef std::remove_all_extents<int[24][60]>::type C;        // int
  typedef std::remove_all_extents<int[][60]>::type D;          // int
  typedef std::remove_all_extents<const int[10]>::type E;      // const int

  std::cout << std::boolalpha;
  std::cout << "typedefs of int:" << std::endl;
  std::cout << "A: " << std::is_same<int,A>::value << std::endl;
  std::cout << "B: " << std::is_same<int,B>::value << std::endl;
  std::cout << "C: " << std::is_same<int,C>::value << std::endl;
  std::cout << "D: " << std::is_same<int,D>::value << std::endl;
  std::cout << "E: " << std::is_same<int,E>::value << std::endl;

  return 0;
}

Output:
typedefs of int:
A: true
B: true
C: true
D: true
E: false


See also

remove_extent
Remove array extent (class template)
extent
Array dimension extent (class template)
rank
Array rank (class template)