std::is_lvalue_reference
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definiert in Header <type_traits>
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template< class T > struct is_lvalue_reference; |
(seit C++11) | |
Wenn
T
ein L-Wert Referenz-Typ ist, stellt das Mitglied konstanten value
gleich true. Für jede andere Art, value
ist false .Original:
If
T
is an lvalue reference 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 lvalue reference type , false anders Original: true if T is an lvalue reference 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
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type
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std::integral_constant<bool, value> |
[Bearbeiten] Mögliche Implementierung
template<class T> struct is_lvalue_reference : std::false_type {}; template<class T> struct is_lvalue_reference<T&> : std::true_type {}; |
[Bearbeiten] Beispiel
#include <iostream> #include <type_traits> class A {}; int main() { std::cout << std::boolalpha; std::cout << std::is_lvalue_reference<A>::value << '\n'; std::cout << std::is_lvalue_reference<A&>::value << '\n'; std::cout << std::is_lvalue_reference<A&&>::value << '\n'; std::cout << std::is_lvalue_reference<int>::value << '\n'; std::cout << std::is_lvalue_reference<int&>::value << '\n'; std::cout << std::is_lvalue_reference<int&&>::value << '\n'; }
Output:
false true false false true false
[Bearbeiten] Siehe auch
(C++11) |
prüft, ob ein Typ ist entweder lvalue Verweis oder rvalue Verweis Original: checks if a type is either lvalue reference or rvalue reference 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 rvalue Verweis Original: checks if a type is rvalue reference The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (Klassen-Template) |