std::rank - cppreference.com

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Definido no cabeçalho `<type_traits>`

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

If T is an array type, provides the member constant value equal to the number of dimensions of the array. For any other type, value is 0.

Herdado de std::integral_constant

Member constants


	the number of dimensions of `T` or zero (membro estático público constante)

Member functions


	converte o objeto em `std::size_t`, retorna `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. (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`	`std::size_t`

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

Possível implementação

template<class T>
struct rank : std::integral_constant<std::size_t, 0> {};

template<class T>
struct rank<T[]> : public std::integral_constant<std::size_t, rank<T>::value + 1> {};

template<class T, size_t N>
struct rank<T[N]> : public std::integral_constant<std::size_t, rank<T>::value + 1> {};

Exemplo

#include <iostream>
#include <type_traits>

int main()
{
    std::cout << std::rank<int[1][2][3]>::value << '\n';
    std::cout << std::rank<int[][2][3][4]>::value << '\n';
    std::cout << std::rank<int>::value << '\n';
}

Saída:

Veja também


is_array (C++11)	verifica se o tipo é um tipo de matriz 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. (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]