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std::is_enum

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

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.

Template parameters

a type to check

Helper variable template

template< class T >
inline constexpr bool is_enum_v = is_enum<T>::value;

(since C++17)

Inherited from std::integral_constant

Member constants

value

[static]

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

Member functions

operator bool	converts the object to `bool`, returns `value` (public member function)
operator() (C++14)	returns `value` (public member function)

Member types

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

Example

#include <iostream>
#include <type_traits>
 
class A {};
 
enum E {};
 
enum class Ec : int {};
 
int main() 
{
    std::cout << std::boolalpha;
    std::cout << std::is_enum<A>::value << '\n';
    std::cout << std::is_enum<E>::value << '\n';
    std::cout << std::is_enum<Ec>::value << '\n';
    std::cout << std::is_enum<int>::value << '\n';
}

Output:

false
true
true
false

is_integral (C++11)	checks if a type is integral type (class template)
is_arithmetic (C++11)	checks if a type is arithmetic type (class template)