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is_enum Class

Tests if type is an enumeration.

Syntax

template <class Ty>
struct is_enum;

Parameters

Ty
The type to query.

Remarks

An instance of the type predicate holds true if the type Ty is an enumeration type or a cv-qualified form of an enumeration type, otherwise it holds false.

Example

// std__type_traits__is_enum.cpp
// compile with: /EHsc
#include <type_traits>
#include <iostream>

struct trivial
    {
    int val;
    };

enum color {
    red, greed, blue};

int main()
    {
    std::cout << "is_enum<trivial> == " << std::boolalpha
        << std::is_enum<trivial>::value << std::endl;
    std::cout << "is_enum<color> == " << std::boolalpha
        << std::is_enum<color>::value << std::endl;
    std::cout << "is_enum<int> == " << std::boolalpha
        << std::is_enum<int>::value << std::endl;

    return (0);
    }
is_enum<trivial> == false
is_enum<color> == true
is_enum<int> == false

Requirements

Header: <type_traits>

Namespace: std

See also

<type_traits>
is_integral Class