std::is_fundamental
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definiert in Header <type_traits>
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template< class T > struct is_fundamental; |
(seit C++11) | |
Wenn
T
eine grundlegende Art (das heißt, ein arithmetischer Typ, void oder nullptr_t) ist, stellt das Mitglied konstanten value
gleich true. Für jede andere Art, value
ist false .Original:
If
T
is a fundamental type (that is, arithmetic type, void, or nullptr_t), 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 a fundamental type , false anders Original: true if T is a fundamental 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
|
type
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std::integral_constant<bool, value> |
[Bearbeiten] Mögliche Implementierung
template< class T> struct is_fundamental : std::integral_constant< bool, std::is_arithmetic<T>::value || std::is_void<T>::value || std::is_same<std::nullptr_t, typename std::remove_cv<T>::type>::value > {}; |
[Bearbeiten] Beispiel
#include <iostream> #include <type_traits> class A {}; int main() { std::cout << std::boolalpha; std::cout << std::is_fundamental<A>::value << '\n'; std::cout << std::is_fundamental<int>::value << '\n'; std::cout << std::is_fundamental<int&>::value << '\n'; std::cout << std::is_fundamental<int*>::value << '\n'; std::cout << std::is_fundamental<float>::value << '\n'; std::cout << std::is_fundamental<float&>::value << '\n'; std::cout << std::is_fundamental<float*>::value << '\n'; }
Output:
false true false false true false false
[Bearbeiten] Siehe auch
(C++11) |
prüft, ob ein Typ Verbindungstyp Original: checks if a type is compound 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 arithmetischen Typ Original: checks if a type is arithmetic 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 void Original: checks if a type is void The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Klassen-Template) |