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

NAME
       std::is_compound	- std::is_compound

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

	  If  T	 is a compound type (that is, array, function, object pointer,
       function	pointer,
	  member object	pointer, member	function  pointer,  reference,	class,
       union, or
	  enumeration, including any cv-qualified variants), provides the mem-
       ber constant
	  value	equal true. For	any other type,	value is false.

	  The behavior of a program that adds specializations for is_compound
	  or is_compound_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_compound_v =	is_compound<T>::value;

       Inherited from std::integral_constant

Member constants
	  value	   true	if T is	a compound 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>

Notes
	  Compound  types  are the types that are constructed from fundamental
       types. Any C++
	  type is either fundamental or	compound.

Possible implementation
	  template< class T >
	  struct is_compound : std::integral_constant<bool, !std::is_fundamen-
       tal<T>::value> {};

Example
       // Run this code

	#include <iostream>
	#include <type_traits>

	int main() {
	    class cls {};
	    std::cout << (std::is_compound<cls>::value
			     ? "`cls` is compound"
			     : "`cls` is not a compound") << '\n';
	    std::cout << (std::is_compound_v<int>
			     ? "`int` is compound"
			     : "`int` is not a compound") << '\n';
	}

Output:
	`cls` is compound
	`int` is not a compound

See also
	  is_fundamental checks	if a type is a fundamental type
	  (C++11)	 (class	template)
	  is_scalar	 checks	if a type is a scalar type
	  (C++11)	 (class	template)
	  is_object	 checks	if a type is an	object type
	  (C++11)	 (class	template)
	  is_array	 checks	if a type is an	array type
	  (C++11)	 (class	template)

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

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