std::is_array
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definiert in Header <type_traits> | ||
template<class T > struct is_array; | (seit C++11) | |
Wenn
T
ein Array-Typ ist, stellt das Mitglied konstanten value
gleich true. Für jede andere Art, value
ist false .Original:
If
T
is an array type, 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.
Inhaltsverzeichnis |
Inherited from std::integral_constant
Member constants
value [statisch] | true wenn T is an array type , false anders Original: true if T is an array 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 | bool |
type | std::integral_constant<bool, value> |
[Bearbeiten]Mögliche Implementierung
template<class T>struct is_array :std::false_type{}; template<class T>struct is_array<T[]>:std::true_type{}; template<class T, std::size_t N>struct is_array<T[N]>:std::true_type{}; |
[Bearbeiten]Beispiel
#include <iostream>#include <type_traits> class A {}; int main(){std::cout<<std::boolalpha;std::cout<< std::is_array<A>::value<<'\n';std::cout<< std::is_array<A[3]>::value<<'\n';std::cout<< std::is_array<float>::value<<'\n';std::cout<< std::is_array<int>::value<<'\n';std::cout<< std::is_array<int[3]>::value<<'\n';}
Output:
false true false false true
[Bearbeiten]Siehe auch
(C++11) | ermittelt die Anzahl der Dimensionen eines Array-Typ Original: obtains the number of dimensions of 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) | erhält die Größe eines Array-Typs entlang einer bestimmten Dimension Original: obtains the size of an array type along a specified dimension 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) | Entfernt ein Teil aus dem angegebenen Array-Typ Original: removes one extent from the given 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) | removes all extents from the given array type (Klassen-Template) |