std::is_array - cppreference.com

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Definido no cabeçalho `<type_traits>`

`template< class T > struct is_array;`		(desde C++11)

Se T é um tipo de matriz, fornece o membro constante value true igual. Para qualquer outro tipo, é value false.

Original:

If T is an array type, provides the member constant value equal true. For any other type, value is false.

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Herdado de std::integral_constant

Member constants


	`true` se `T` is an array type , `false` contrário Original: `true` if `T` is an array 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. (membro estático público constante)

Member functions


	converte o objeto em `bool`, retorna `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. (função pública membro)

Member types


Tipo 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`

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

Possível implementação

template<class T>
struct is_array : std::false_type {};

template<class T>
struct is_array<T[]> : std::true_type {};

template<class T, std::size_t N>
struct is_array<T[N]> : std::true_type {};

Exemplo

#include <iostream>
#include <type_traits>

class A {};

int main() 
{
    std::cout << std::boolalpha;
    std::cout << std::is_array<A>::value << '\n';
    std::cout << std::is_array<A[3]>::value << '\n';
    std::cout << std::is_array<float>::value << '\n';
    std::cout << std::is_array<int>::value << '\n';
    std::cout << std::is_array<int[3]>::value << '\n';
}

Saída:

false
true
false
false
true

Veja também


rank (C++11)	obtém o número de dimensões de um tipo de matriz Original: obtains the number of dimensions of 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. (modelo de classe) [edit]

extent (C++11)	obtém o tamanho de um tipo de matriz ao longo de uma dimensão especificada Original: obtains the size of an array type along a specified dimension The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (modelo de classe) [edit]

remove_extent (C++11)	remove uma medida do tipo matriz dada Original: removes one extent from the given array type The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (modelo de classe) [edit]

remove_all_extents (C++11)	removes all extents from the given array type (modelo de classe) [edit]