std::is_member_pointer - cppreference.com

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Definido no cabeçalho `<type_traits>`

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

Se T é ponteiro para não-estático objeto membro ou um ponteiro para não-estático função de membro, fornece o membro constante value true igual. Para qualquer outro tipo, é value false.

Original:

If T is pointer to non-static member object or a pointer to non-static member function, provides the member constant value equal true. For any other type, value is false.

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You can help to correct and verify the translation. Click here for instructions.

Herdado de std::integral_constant

Member constants


	`true` se `T` is a member pointer type , `false` contrário Original: `true` if `T` is a member 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


	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_member_pointer_helper         : std::false_type {};

template< class T, class U >
struct is_member_pointer_helper<T U::*> : std::true_type {};

template< class T >
struct is_member_pointer : 
    is_member_pointer_helper<typename std::remove_cv<T>::type> {};

Exemplo

#include <iostream>
#include <type_traits>

int main() {
    class cls {};
    std::cout << (std::is_member_pointer<int(cls::*)>::value
                     ? "T is member pointer"
                     : "T is not a member pointer") << '\n';
    std::cout << (std::is_member_pointer<int>::value
                     ? "T is member pointer"
                     : "T is not a member pointer") << '\n';
}

Saída:

T is member pointer
T is not a member pointer

Veja também


is_pointer (C++11)	verifica se um tipo é um tipo de ponteiro Original: checks if a type is a pointer 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]

is_member_object_pointer (C++11)	verifica se um tipo é um ponteiro para um objeto membro não-estático Original: checks if a type is a pointer to a non-static member object 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]

is_member_function_pointer (C++11)	verifica se um tipo é um ponteiro para uma função membro não-estático Original: checks if a type is a pointer to a non-static member function 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]

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