std::is_base_of
From cppreference.com
                    
                                        
                    
                    
                                                            
                    |   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.
Requires that Derived is a complete type if it is not the same type as Base and if both Base and Derived are class types.
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> | 
[edit] Example
Run this code
#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