std::is_pointer
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Déclaré dans l'en-tête <type_traits>
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template< class T > struct is_pointer; |
(depuis C++11) | |
Si
T
est un type pointeur d'objet ou un type pointeur de fonction (mais pas un pointeur à l'objet membre non-statique ou fonction membre), fournit la value
true membre constant égal. Pour tout autre type, value
est false .Original:
If
T
is an object pointer type or a function pointer type (but not pointer to non-static member object or member function), 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.
Sommaire |
Inherited from std::integral_constant
Member constants
value [ statique ]Original: static The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
true si T is a pointer type , false autrement Original: true if T is a pointer 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. (constante membre statique publique) |
Member functions
operator bool |
convertit l'objet en bool, retourne 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. (fonction membre publique) |
Member types
Type d'
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> |
[modifier] Mise en œuvre possible
template< class T > struct is_pointer_helper : std::false_type {}; template< class T > struct is_pointer_helper<T*> : std::true_type {}; template< class T > struct is_pointer : is_pointer_helper<typename std::remove_cv<T>::type> {}; |
[modifier] Exemple
#include <iostream> #include <type_traits> class A {}; int main() { std::cout << std::boolalpha; std::cout << std::is_pointer<A>::value << '\n'; std::cout << std::is_pointer<A*>::value << '\n'; std::cout << std::is_pointer<float>::value << '\n'; std::cout << std::is_pointer<int>::value << '\n'; std::cout << std::is_pointer<int*>::value << '\n'; std::cout << std::is_pointer<int**>::value << '\n'; }
Résultat :
false true false false true true
[modifier] Voir aussi
(C++11) |
vérifie si un type est un type tableau 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. (classe générique) |
(C++11) |
vérifie si un type est de type scalaire 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. (classe générique) |