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std::is_bounded_array(3)      C++ Standard Libary     std::is_bounded_array(3)

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;

	  std::is_bounded_array	is a UnaryTypeTrait.

	  Checks  whether T is an array	type of	known bound. Provides the mem-
       ber constant value
	  which	is equal to true, if T is an array type	of known bound.	Other-
       wise, value is
	  equal	to false.

	  If the program adds specializations for std::is_bounded_array	or
	  std::is_bounded_array_v, the behavior	is undefined.

Template parameters
	  T - a	type to	check

	  Helper variable template

	  template< class T >
	  inline       constexpr       bool	   is_bounded_array_v	     =
       (since C++20)
	  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
	  [static] (public static member constant)

Member functions
	  operator bool	converts the object to bool, returns value
			(public	member function)
	  operator()	returns	value
	  (C++14)	(public	member function)

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 {};

Notes
		Feature-test  macro	    Value    Std		  Fea-
       ture
	  __cpp_lib_bounded_array_traits 201902L  (C++20)  std::is_bounded_ar-
       ray,
							 std::is_unbounded_ar-
       ray

Example
       // Run this code

	#include <iostream>
	#include <type_traits>

	#define	 OUT(...) std::cout << #__VA_ARGS__ << " : " <<	__VA_ARGS__ <<
       '\n'

	class A	{};

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

Output:
	std::is_bounded_array_v<A> : false
	std::is_bounded_array_v<A[]> : false
	std::is_bounded_array_v<A[3]> :	true
	std::is_bounded_array_v<float> : false
	std::is_bounded_array_v<int> : false
	std::is_bounded_array_v<int[]> : false
	std::is_bounded_array_v<int[3]>	: true

See also
	  is_array	     checks if a type is an array type
	  (C++11)	     (class template)
	  is_unbounded_array checks if a type is  an  array  type  of  unknown
       bound
	  (C++20)	     (class template)
	  extent	      obtains the size of an array type	along a	speci-
       fied dimension
	  (C++11)	     (class template)

http://cppreference.com		  2024.06.10	      std::is_bounded_array(3)

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