std::is_enum

 

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is_default_constructibleis_trivially_default_constructibleis_nothrow_default_constructible (C++11)(C++11)(C++11)
is_copy_constructibleis_trivially_copy_constructibleis_nothrow_copy_constructible (C++11)(C++11)(C++11)
is_move_constructibleis_trivially_move_constructibleis_nothrow_move_constructible (C++11)(C++11)(C++11)
is_assignableis_trivially_assignableis_nothrow_assignable (C++11)(C++11)(C++11)
is_copy_assignableis_trivially_copy_assignableis_nothrow_copy_assignable (C++11)(C++11)(C++11)
is_move_assignableis_trivially_move_assignableis_nothrow_move_assignable (C++11)(C++11)(C++11)
is_destructibleis_trivially_destructibleis_nothrow_destructible (C++11)(C++11)(C++11)
has_virtual_destructor (C++11)
is_swappable_withis_swappableis_nothrow_swappable_withis_nothrow_swappable (C++17)(C++17)(C++17)(C++17)
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is_same (C++11) is_base_of (C++11) is_convertible (C++11)	alignment_of (C++11) rank (C++11) extent (C++11)
is_invocableis_invocable_ris_nothrow_invocableis_nothrow_invocable_r (C++17)(C++17)(C++17)(C++17)
Type modifications
remove_cvremove_constremove_volatile (C++11)(C++11)(C++11) add_cvadd_constadd_volatile (C++11)(C++11)(C++11) make_signed (C++11) make_unsigned (C++11)	remove_reference (C++11) add_lvalue_referenceadd_rvalue_reference (C++11)(C++11) remove_pointer (C++11) add_pointer (C++11) remove_extent (C++11) remove_all_extents (C++11)
Type transformations
aligned_storage (C++11) aligned_union (C++11) decay (C++11) enable_if (C++11) void_t (C++17)	conditional (C++11) common_type (C++11) underlying_type (C++11) result_ofinvoke_result (C++11)(deprecated in C++17)(C++17)

 

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

T

-

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

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

See also

is_void (C++11)	checks if a type is void (class template)
is_pointer (C++11)	checks if a type is a pointer type (class template)
is_arithmetic (C++11)	checks if a type is arithmetic type (class template)