std::is_pointer
Da cppreference.com
 |
This page has been machine-translated from the English version of the wiki using Google Translate.
The translation may contain errors and awkward wording. Hover over text to see the original version. You can help to fix errors and improve the translation. For instructions click here. |
| Definido no cabeçalho <type_traits>
|
||
| template< class T > struct is_pointer; |
(desde C++11) | |
Se
T é um tipo de ponteiro de objeto ou um tipo de ponteiro de função (mas não ponteiro para não-estático objeto membro ou função membro), fornece o membro value true constante igual. Para qualquer outro tipo, é value false.Original:
If
T is an object pointer type or a function pointer type (but not pointer to non-static member object or member function), 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.
Índice |
Herdado de std::integral_constant
Member constants
| value [estática] |
true se T is a pointer type , false contrário Original: true if T is a pointer 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
| operator bool |
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> |
[editar] Possível implementação
template< class T > struct is_pointer_helper : std::false_type {}; template< class T > struct is_pointer_helper<T*> : std::true_type {}; template< class T > struct is_pointer : is_pointer_helper<typename std::remove_cv<T>::type> {}; |
[editar] Exemplo
#include <iostream> #include <type_traits> class A {}; int main() { std::cout << std::boolalpha; std::cout << std::is_pointer<A>::value << '\n'; std::cout << std::is_pointer<A*>::value << '\n'; std::cout << std::is_pointer<float>::value << '\n'; std::cout << std::is_pointer<int>::value << '\n'; std::cout << std::is_pointer<int*>::value << '\n'; std::cout << std::is_pointer<int**>::value << '\n'; }
Saída:
false true false false true true
[editar] Veja também
| (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) |
| (C++11) |
verifica se um tipo é tipo escalar Original: checks if a type is scalar 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) |
