is_base_of Class

Tests whether one type is base of another.

Syntax

template <class Base, class Derived>  
struct is_base_of;  

Parameters

Base
The base class to test for.

Derived
The derived type to test for.

Remarks

An instance of the type predicate holds true if the type Base is a base class of the type Derived, otherwise it holds false.

Example

#include <type_traits>   
#include <iostream>   

struct base   
    {   
    int val;   
    };   

struct derived   
    : public base   
    {   
    };   

int main()   
    {   
    std::cout << "is_base_of<base, base> == " << std::boolalpha   
        << std::is_base_of<base, base>::value << std::endl;   
    std::cout << "is_base_of<base, derived> == " << std::boolalpha   
        << std::is_base_of<base, derived>::value << std::endl;   
    std::cout << "is_base_of<derived, base> == " << std::boolalpha   
        << std::is_base_of<derived, base>::value << std::endl;   

    return (0);   
    }  
is_base_of<base, base> == true  
is_base_of<base, derived> == true  
is_base_of<derived, base> == false  

Requirements

Header: <type_traits>

Namespace: std

See Also

<type_traits>
is_convertible Class