Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help 
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;

	  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.

	  The  behavior	 of  a	 program   that	  adds	 specializations   for
       is_bounded_array	or
	  is_bounded_array_v 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: __cpp_lib_bounded_array_traits

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		  2022.07.31	      std::is_bounded_array(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=std::is_bounded_array&sektion=3&manpath=FreeBSD+Ports+15.0>

home | help