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

NAME
       std::is_unbounded_array - std::is_unbounded_array

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

	  std::is_unbounded_array is a UnaryTypeTrait.

	  Checks  whether T is an arrays of unknown bound. Provides the	member
       constant	value
	  which	is equal to true, if T is an array type	of unknown bound. Oth-
       erwise, value is
	  equal	to false.

	  If the program adds specializations for std::is_unbounded_array or
	  std::is_unbounded_array_v, the behavior is undefined.

Template parameters
	  T - a	type to	check

	  Helper variable template

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

       Inherited from std::integral_constant

Member constants
	  value	    true if T is an array type of unknown bound., false	other-
       wise
	  [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_unbounded_array: std::false_type {};

	  template<class T>
	  struct is_unbounded_array<T[]> : 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 <type_traits>

	class A	{};

	static_assert
	(""
	    && std::is_unbounded_array_v<A> == false
	    && std::is_unbounded_array_v<A[]> == true
	    && std::is_unbounded_array_v<A[3]> == false
	    && std::is_unbounded_array_v<float>	== false
	    && std::is_unbounded_array_v<int> == false
	    && std::is_unbounded_array_v<int[]>	== true
	    && std::is_unbounded_array_v<int[3]> == false
	);

	int main() {}

See also
	  is_array	   checks if a type is an array	type
	  (C++11)	   (class template)
	  is_bounded_array checks if a type is an array	type of	known bound
	  (C++20)	   (class template)
	  extent	   obtains the size of an array	type along a specified
       dimension
	  (C++11)	   (class template)

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

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