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

NAME
       std::is_enum - std::is_enum

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

	  Checks  whether  T  is an enumeration	type. Provides the member con-
       stant value which is
	  equal	to true, if T is an  enumeration  type.	 Otherwise,  value  is
       equal to	false.

	  The behavior of a program that adds specializations for is_enum
	  or is_enum_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_enum_v = is_enum<T>::value;

       Inherited from std::integral_constant

Member constants
	  value	   true	if T is	an enumeration 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>

Example
       // Run this code

	#include <iostream>
	#include <type_traits>

	struct A { enum	E { }; };

	enum E {};

	enum class Ec :	int {};

	int main()
	{
	    std::cout
		<< std::boolalpha
		<< std::is_enum<A>::value << '\n'
		<< std::is_enum<E>::value << '\n'
		<< std::is_enum<A::E>()	<< '\n'
		<<  std::is_enum_v<int>	 <<  '\n' // Uses helper variable tem-
       plate (C++17)
		<< std::is_enum_v<Ec> << '\n'; // Uses	helper	variable  tem-
       plate (C++17)
	}

Output:
	false
	true
	true
	false
	true

See also
	  is_integral	 checks	if a type is an	integral type
	  (C++11)	 (class	template)
	  is_arithmetic	 checks	if a type is an	arithmetic type
	  (C++11)	 (class	template)
	  is_scalar	 checks	if a type is a scalar type
	  (C++11)	 (class	template)
	  is_scoped_enum checks	if a type is a scoped enumeration type
	  (C++23)	 (class	template)

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

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