is_base_of Class
Tests if one type is base of another.
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
// std_tr1__type_traits__is_base_of.cpp
// compile with: /EHsc
#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::tr1::is_base_of<base, base>::value << std::endl;
std::cout << "is_base_of<base, derived> == " << std::boolalpha
<< std::tr1::is_base_of<base, derived>::value << std::endl;
std::cout << "is_base_of<derived, base> == " << std::boolalpha
<< std::tr1::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::tr1