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

NAME
       std::is_array - std::is_array

Synopsis
	  Defined in header <type_traits>
	  template< class T >		   (since C++11)
	  struct is_array;

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

	  The behavior of a program that adds specializations for is_array
	  or is_array_v
	  (since C++17)	is undefined.

Template parameters
	  T - a	type to	check

	 Helper	variable template

	  template<  class  T	>					(since
       C++17)
	  inline constexpr bool	is_array_v = is_array<T>::value;

       Inherited from std::integral_constant

Member constants
	  value	   true	if T is	an array type ,	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_array : std::false_type {};

	  template<class T>
	  struct is_array<T[]> : std::true_type	{};

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

Example
       // Run this code

	#include <array>
	#include <iostream>
	#include <type_traits>

	class A	{};

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

Output:
	false
	true
	true
	false
	false
	true
	true
	false

See also
	  is_bounded_array   checks if a type is an array type of known	bound
	  (C++20)	     (class template)
	  is_unbounded_array  checks  if  a  type  is an array type of unknown
       bound
	  (C++20)	     (class template)
	  rank		     obtains the number	of dimensions of an array type
	  (C++11)	     (class template)
	  extent	     obtains the size of an array type along a	speci-
       fied dimension
	  (C++11)	     (class template)
	  remove_extent	     removes one extent	from the given array type
	  (C++11)	     (class template)
	  remove_all_extents removes all extents from the given	array type
	  (C++11)	     (class template)

http://cppreference.com		  2022.07.31		      std::is_array(3)

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