std::is_polymorphic — cppreference.com

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Déclaré dans l'en-tête `<type_traits>`
`template< class T > struct is_polymorphic;`		(depuis C++11)

Si T est une classe polymorphe (c'est à dire une classe qui hérite déclare ou au moins une fonction virtuelle), fournit du membre de constante value true égale. Pour tout autre type, value est false .

Original:

If T is a polymorphic class (that is, a class that declares or inherits at least one virtual function), provides the member constant value equal true. For any other type, value is false.

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Inherited from std::integral_constant

Member constants


value [ statique Original: static The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. ]	`true` si `T` is a polymorphic class type , `false` autrement Original: `true` if `T` is a polymorphic class type , `false` otherwise The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (constante membre statique publique)

Member functions


	convertit l'objet en `bool`, retourne `value` Original: converts the object to `bool`, returns `value` The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (fonction membre publique)

Member types


Type d' Original: Type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.	Definition

`value_type`	`bool`

`type`	`std::integral_constant<bool, value>`

Notes

Seules les classes polymorphes contiennent caché des informations RTTI qui permet d'examiner et de les convertir avec

dynamic_cast

Original:

Only polymorphic classes contain hidden RTTI information which makes it possible to examine and convert them with

dynamic_cast

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Exemple

#include <iostream>
#include <type_traits>

struct A {
    int m;
};

struct B {
    virtual void foo();
};

struct C : B {};

int main()
{
    std::cout << std::boolalpha;
    std::cout << std::is_polymorphic<A>::value << '\n';
    std::cout << std::is_polymorphic<B>::value << '\n';
    std::cout << std::is_polymorphic<C>::value << '\n';
}

Résultat :

Voir aussi


	checks if a type is a class type (but not union type) (classe générique) [edit]

	vérifie si un type est le type de classe abstraite Original: checks if a type is abstract class type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (classe générique) [edit]