std::is_object – cppreference.com

Aus cppreference.com

definiert in Header `<type_traits>`

`template< class T > struct is_object;`		(seit C++11)

Wenn T ein Objekttyp ist (das heißt, Skalar, Array, Klasse oder Union) sieht das Mitglied konstanten value gleich true. Für jede andere Art, value ist false .

Original:

If T is an object type (that is, scalar, array, class, or union), provides the member constant value equal true. For any other type, value is false.

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

Inherited from std::integral_constant

Member constants


	`true` wenn `T` is an object type , `false` anders Original: `true` if `T` is an object 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. (public static Mitglied konstanten)

Member functions


	wandelt das Objekt `bool`, gibt `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. (öffentliche Elementfunktion)

Member types


Type 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>`

Mögliche Implementierung

template< class T>
struct is_object : std::integral_constant<bool,
                     std::is_scalar<T>::value ||
                     std::is_array<T>::value  ||
                     std::is_union<T>::value  ||
                     std::is_class<T>::value> {};

Beispiel

#include <iostream>
#include <type_traits>

int main() {
    class cls {};
    std::cout << std::boolalpha;
    std::cout << std::is_object<int>::value << '\n';
    std::cout << std::is_object<int&>::value << '\n';
    std::cout << std::is_object<cls>::value << '\n';
    std::cout << std::is_object<cls&>::value << '\n';
}

Output:

Siehe auch


is_scalar (C++11)	prüft, ob ein Typ ist skalaren Typ Original: checks if a type is scalar type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Klassen-Template) [edit]

is_array (C++11)	prüft, ob ein Typ ist ein Array-Typ Original: checks if a type is an array type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Klassen-Template) [edit]

is_union (C++11)	prüft, ob ein Typ ist ein union-Typ Original: checks if a type is an union type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Klassen-Template) [edit]

is_class (C++11)	checks if a type is a class type (but not union type) (Klassen-Template) [edit]