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nullptr pointer literal

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Índice

[editar] Sintaxe

nullptr (desde C++11)

[editar] Explicação

A palavra-chave nullptr denota o ponteiro nulo literal. É um prvalue não especificado de std::nullptr_t tipo. Existem <div class="t-tr-text">conversões implícitas
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implicit conversions
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de nullptr ao valor de ponteiro nulo de qualquer tipo de ponteiro e qualquer ponteiro para tipo de membro. Conversões semelhantes existem para qualquer valor de std::nullptr_t tipo, bem como para o NULL macro, o ponteiro nulo constante.
Original:
The keyword nullptr denotes the null pointer literal. It is an unspecified prvalue of type std::nullptr_t. There exist
conversões implícitas
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implicit conversions
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</div> from nullptr to null pointer value of any pointer type and any pointer to member type. Similar conversions exist for any value of type std::nullptr_t as well as for the macro NULL, the null pointer constant.
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[editar] Exemplo

Demonstra como nullptr permite o encaminhamento através de uma função de modelo .
Original:
Demonstrates how nullptr allows forwarding via a template function.
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#include <cstddef>
#include <iostream>
 
template<class F, class A>
void Fwd(F f, A a)
{
    f(a);
}
 
void g(int* i)
{
    std::cout << "Function g called\n";
}
 
int main()
{
    g(NULL);           // Fine
    g(0);              // Fine
 
    Fwd(g, nullptr);   // Fine
//  Fwd(g, NULL);  // ERROR: No function g(int)
}

Saída: 

Function g called
Function g called
Function g called

[editar] Palavras-chave

nullptr

[editar] Veja também
definida pela implementação ponteiro nulo constante
Original:
implementation-defined null pointer constant
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(macro constante) [edit]
(C++11)
o tipo de nullptr ponteiro nulo literal
Original:
the type of the null pointer literal nullptr
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(typedef) [edit]
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