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std::is_base_of

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Revision as of 16:50, 1 July 2013 by P12bot (Talk | contribs)

 
 
 
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is_base_of
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Defined in header <type_traits>
template< class Base, class Derived >
struct is_base_of;
(since C++11)

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

Contents

Inherited from std::integral_constant

Member constants

value
[static]
true if Derived is derived from Base , false otherwise
(public static member constant)

Member functions

operator bool
converts the object to bool, returns value
(public member function)

Member types

Type Definition
value_type bool
type std::integral_constant<bool, value>

Example

#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