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

NAME
       std::is_scoped_enum - std::is_scoped_enum

Synopsis
	  Defined in header <type_traits>
	  template< class T >		   (since C++23)
	  struct is_scoped_enum;

	  std::is_scoped_enum is a UnaryTypeTrait.

	  Checks  whether  T is	a scoped enumeration type. Provides the	member
       constant	value
	  which	is equal to true, if T is a scoped  enumeration	 type.	Other-
       wise, value is equal
	  to false.

	  If the program adds specializations for std::is_scoped_enum or
	  std::is_scoped_enum_v, the behavior is undefined.

Template parameters
	  T - a	type to	check

	  Helper variable template

	  template<		     class		   T		     >
       (since C++23)
	  inline constexpr bool	is_scoped_enum_v = is_scoped_enum<T>::value;

       Inherited from std::integral_constant

Member constants
	  value	   true	if T is	a scoped 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>

Notes
	     Feature-test macro	    Value    Std	 Feature
	  __cpp_lib_is_scoped_enum 202011L (C++23) std::is_scoped_enum

Possible implementation
	  template<typename E>
	  struct is_scoped_enum	: std::bool_constant<requires
	  {
	      requires std::is_enum_v<E>;
	      requires !std::is_convertible_v<E, std::underlying_type_t<E>>;
	  }>
	  {};

Example
       // Run this code

	#include <type_traits>

	class A	{};

	enum E {};

	enum struct Es { oz };

	enum class Ec :	int {};

	int main()
	{
	    static_assert(std::is_scoped_enum_v<A> == false);
	    static_assert(std::is_scoped_enum_v<E> == false);
	    static_assert(std::is_scoped_enum_v<Es> == true);
	    static_assert(std::is_scoped_enum_v<Ec> == true);
	    static_assert(std::is_scoped_enum_v<int> ==	false);
	}

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_enum	checks if a type is an enumeration type
	  (C++11)	(class template)

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

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