std::is_trivial
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| Défini dans l'en-tête <type_traits>
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| template< class T > struct is_trivial; |
(depuis C++11) | |
Si
T est un type trivial (c'est à dire un type scalaire, une classe trivialement copiable avec un constructeur par défaut insignifiant, ou un tableau de ce type / classe, peut-cv-qualifié), fournit du membre de constante value true égale. Pour tout autre type, value est false .Original:
If
T is a trivial type (that is, a scalar type, a trivially copyable class with a trivial default constructor, or array of such type/class, possibly cv-qualified), 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 trivial type , false autrement Original: true if T is a trivial 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] Notes
Seuls les objets (y compris les tableaux) de type trivial peut être créé par un appel à std::malloc .
Original:
Only objects (including arrays) of trivial type may be created by a call to std::malloc.
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[modifier] Mise en œuvre possible
template< class T > struct is_trivial : std::integral_constant< bool, std::is_trivially_copyable<T>::value && std::is_trivially_default_constructible<T>::value > {}; |
[modifier] Exemple
#include <iostream> #include <type_traits> struct A { int m; }; struct B { B() {} }; int main() { std::cout << std::boolalpha; std::cout << std::is_trivial<A>::value << '\n'; std::cout << std::is_trivial<B>::value << '\n'; }
Résultat :
true false
[modifier] Voir aussi
| (C++11) |
checks if a type is trivially copyable (classe générique) |