is-polymorphic-class.md

description	title	ms.date	f1_keywords	helpviewer_keywords	ms.assetid
Learn more about: is_polymorphic Class	is_polymorphic Class	11/04/2016	type_traits/std::is_polymorphic	is_polymorphic class is_polymorphic	4e1704db-d6f9-4154-a100-0ba02a373f20

is_polymorphic Class

Tests if type has a virtual function.

Syntax

template <class Ty>
struct is_polymorphic;

Parameters

Ty
The type to query.

Remarks

An instance of the type predicate holds true if the type Ty is a class that declares or inherits a virtual function, otherwise it holds false.

Example

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

struct trivial
    {
    int val;
    };

struct throws
    {
    throws() throw(int)
        {
        }

    throws(const throws&) throw(int)
        {
        }

    throws& operator=(const throws&) throw(int)
        {
        }

    virtual ~throws()
        {
        }

    int val;
    };

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

    return (0);
    }

is_polymorphic<trivial> == false
is_polymorphic<throws> == true

Requirements

Header: <type_traits>

Namespace: std

See also

<type_traits>
is_abstract Class