std::is_enum (3) - Linux Manuals

std::is_enum: std::is_enum

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 constant value which is equal to true, if T is an enumeration type . Otherwise, value is equal to false.

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
         (public static member constant)
[static]

Member functions

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

operator() returns value
              (public member function)
(C++14)

Member types

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

Example

// Run this code

  #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