std::is_bounded_array (3) - Linux Man Pages

std::is_bounded_array: std::is_bounded_array

NAME

std::is_bounded_array - std::is_bounded_array

Synopsis


Defined in header <type_traits>
template< class T > (since C++20)
struct is_bounded_array;


Checks whether T is an array type of known bound. Provides the member constant value which is equal to true, if T is an array type of known bound. Otherwise, value is equal to false.

Template parameters


T - a type to check


Helper variable template


template< class T > (since C++20)
inline constexpr bool is_bounded_array_v = is_bounded_array<T>::value;


Inherited from std::integral_constant

Member constants


value true if T is an array type of known bound , false otherwise
         (public static member constant)
[static]

Member functions


              converts the object to bool, returns value
operator bool (public member function)


operator() returns value
              (public member function)
(C++14)

Member types


Type Definition
value_type bool
type std::integral_constant<bool, value>

Possible implementation


  template<class T>
  struct is_bounded_array: std::false_type {};


  template<class T, std::size_t N>
  struct is_bounded_array<T[N]> : std::true_type {};

Example


// Run this code


  #include <iostream>
  #include <type_traits>


  class A {};


  int main()
  {
      std::cout << std::boolalpha;
      std::cout << std::is_bounded_array_v<A> << '\n';
      std::cout << std::is_bounded_array_v<A[]> << '\n';
      std::cout << std::is_bounded_array_v<A[3]> << '\n';
      std::cout << std::is_bounded_array_v<float> << '\n';
      std::cout << std::is_bounded_array_v<int> << '\n';
      std::cout << std::is_bounded_array_v<int[]> << '\n';
      std::cout << std::is_bounded_array_v<int[3]> << '\n';
  }

Output:


  false
  false
  true
  false
  false
  false
  true

See also


is_array checks if a type is an array type
                   (class template)
(C++11)


is_unbounded_array checks if a type is an array type of unknown bound
                   (class template)
(C++20)


extent obtains the size of an array type along a specified dimension
                   (class template)
(C++11)