std::is_base_of - cppreference.com

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Definido no cabeçalho `<type_traits>`

`template< class B, class D > struct is_base_of;`		(desde C++11)

Se D é derivado B ou se ambos são a classe de não-união mesmo, proporciona o membro value constante igual a true. Caso contrário value é false.

Original:

If D is derived from B or if both are the same non-union class, provides the member constant value equal to true. Otherwise value is false.

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Herdado de std::integral_constant

Member constants


	`true` se `D` is derived from `B` , `false` contrário Original: `true` if `D` is derived from `B` , `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>`

Exemplo

#include <iostream>
#include <type_traits>

class A {};

class B : A {};

class C {};

int main() 
{
    std::cout << std::boolalpha;
    std::cout << "a2b: " << std::is_base_of<A, B>::value << '\n';
    std::cout << "b2a: " << std::is_base_of<B, A>::value << '\n';
    std::cout << "c2b: " << std::is_base_of<C, B>::value << '\n';
}

Saída:

a2b: true
b2a: false
c2b: false