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is_enum Class

Tests if type is an enumeration.

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_tr1__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

Reference

<type_traits>

is_integral Class