std::alignment_of — cppreference.com

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Déclaré dans l'en-tête `<type_traits>`
`template< class T > struct alignment_of;`		(depuis C++11)

Fournit le membre de constante value égale à l'exigence de l'alignement de la T type, si elle est obtenue par une expression alignof. Si T est un type tableau, renvoie les exigences d'alignement du type d'élément .

Original:

Provides the member constant value equal to the alignment requirement of the type T, as if obtained by an alignof expression. If T is an array type, returns the alignment requirements of the element type.

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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. ]	`alignof(typename std::remove_all_extents<T>::type)` (constante membre statique publique)

Member functions


	convertit l'objet en `std::size_t`, retourne `value` Original: converts the object to `std::size_t`, 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`	`std::size_t`

`type`	`std::integral_constant<std::size_t, value>`

Mise en œuvre possible

template< class T >
struct alignment_of : std::integral_constant<
                          std::size_t,
                          alignof(typename std::remove_all_extents<T>::type)
                       > {};

Exemple

#include <iostream>
#include <type_traits>
 
class A {};
 
int main() 
{
    std::cout << std::alignment_of<A>::value << '\n';
    std::cout << std::alignment_of<int>::value << '\n';
    std::cout << std::alignment_of<double>::value << '\n';
}

Résultat :

Voir aussi


alignof operator	queries alignment requirements of a type (depuis C++11) [edit]

aligned_storage (C++11)	définit le type approprié pour une utilisation comme stockage non initialisée pour les types de taille donnée Original: defines the type suitable for use as uninitialized storage for types of given size The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (classe générique) [edit]

aligned_union (C++11)	définit le type approprié pour être utilisé comme stockage non initialisée pour tous les types de données Original: defines the type suitable for use as uninitialized storage for all given types The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (classe générique) [edit]

max_align_t (C++11)	Type de POD avec une exigence d'alignement aussi grand que n'importe quel autre type scalaire (typedef) [edit]