std::is_base_of
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<metanoindex/>
<tbody> </tbody>| definiert in Header <type_traits>
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template< class B, class D > struct is_base_of; |
(seit C++11) | |
Wenn
D von B oder abgeleitet wird beide das gleiche nicht gewerkschaftlich Klasse sind, bietet das Mitglied konstanten value gleich true. Ansonsten value ist 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.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.
Inherited from std::integral_constant
Member constants
value [statisch] |
true wenn D is derived from B , false anders 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. (public static Mitglied konstanten) |
Member functions
operator bool |
wandelt das Objekt bool, gibt 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. (öffentliche Elementfunktion) |
Member types
Type
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
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bool
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type
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std::integral_constant<bool, value>
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Beispiel
#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';
}
Output:
a2b: true
b2a: false
c2b: false