std::is_enum - cppreference.com

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template< class T > struct is_enum;		(since C++11)

std::is_enum is a UnaryTypeTrait.

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

If the program adds specializations for std::is_enum or std::is_enum_v, the behavior is undefined.

Template parameters

Helper variable template

template< class T > constexpr bool is_enum_v = is_enum<T>::value;		(since C++17)

Inherited from std::integral_constant

Member constants

true if T is an enumeration type, false otherwise
(public static member constant)

Member functions

	converts the object to `bool`, returns `value` (public member function)
	returns `value` (public member function)

Member types

Type	Definition
`value_type`	`bool`
`type`	`std::integral_constant<bool, value>`

Example

#include <type_traits>

struct A { enum E {}; };
static_assert(std::is_enum_v<A> == false);
static_assert(std::is_enum_v<A::E> == true);

enum E {};
static_assert(std::is_enum_v<E> == true);

enum class Ec : int {};
static_assert(std::is_enum_v<Ec> == true);

static_assert(std::is_enum_v<int> == false);

int main() {}