std::rank
De cppreference.com
<metanoindex/>
<tbody> </tbody>| 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
value [estática] |
the number of dimensions of T or zero (membro estático público constante) |
Member functions
operator std::size_t |
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:
3
4
0