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

NAME
       std::is_object -	std::is_object

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

	  If T is an object type (that is any possibly cv-qualified type other
       than function,
	  reference,  or void types), provides the member constant value equal
       true. For any
	  other	type, value is false.

	  The behavior of a program that adds specializations for is_object
	  or is_object_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_object_v = is_object<T>::value;

       Inherited from std::integral_constant

Member constants
	  value	   true	if T is	an object 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_object : std::integral_constant<bool,
			       std::is_scalar<T>::value	||
			       std::is_array<T>::value	||
			       std::is_union<T>::value	||
			       std::is_class<T>::value>	{};

Example
       // Run this code

	#include <iostream>
	#include <type_traits>

	int main() {
	    class cls {};
	    std::cout << std::boolalpha;
	    std::cout << std::is_object<int>::value << '\n';
	    std::cout << std::is_object<int&>::value <<	'\n';
	    std::cout << std::is_object<cls>::value << '\n';
	    std::cout << std::is_object<cls&>::value <<	'\n';
	}

Output:
	true
	false
	true
	false

See also
	  is_scalar checks if a	type is	a scalar type
	  (C++11)   (class template)
	  is_array  checks if a	type is	an array type
	  (C++11)   (class template)
	  is_union  checks if a	type is	an union type
	  (C++11)   (class template)
	  is_class  checks if a	type is	a non-union class type
	  (C++11)   (class template)

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

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