std::is_object
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<metanoindex/>
<tbody> </tbody>| definiert in Header <type_traits>
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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.
You can help to correct and verify the translation. Click here for instructions.
Inherited from std::integral_constant
Member constants
value [statisch] |
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
operator bool |
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
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bool
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type
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std::integral_constant<bool, value>
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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> {};
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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:
true
false
true
false
Siehe auch
(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) |
(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) |
(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) |
(C++11) |
checks if a type is a class type (but not union type) (Klassen-Template) |