std::bad_typeid - cppreference.com

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Definido no cabeçalho `<typeinfo>`

`class bad_typeid : public std::exception;`

Uma excepção deste tipo é lançada quando um operador

typeid

é aplicada para um valor nulo dereferenced ponteiro ou um tipo polimórfico.

Original:

An exception of this type is thrown when a

typeid

operator is applied to a dereferenced null pointer value or a polymorphic type.

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Inheritance diagram

Funções de membro


	constrói um objeto `bad_typeid` novo Original: constructs a new `bad_typeid` object 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)

Herdado de std::exception

Member functions


	destrói o objeto de exceção Original: destructs the exception object The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (of `std::exception` função pública virtual membro) [edit]

	retorna uma cadeia explicativa Original: returns an explanatory string The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (of `std::exception` função pública virtual membro) [edit]

Exemplo

#include <iostream>
#include <typeinfo>

struct S { // The type has to be polymorphic
    virtual void f();
}; 

int main()
{
    S* p = nullptr;
    try {
        std::cout << typeid(*p).name() << '\n';
    } catch(const std::bad_typeid& e) {
        std::cout << e.what() << '\n';
    }
}

Saída:

Attempted a typeid of NULL pointer!