std::has_virtual_destructor

 

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Defined in header <type_traits>
template< class T > struct has_virtual_destructor;		(since C++11)

If T is a type with a virtual destructor, provides the member constant value equal true. For any other type, value is false.

Inherited from std::integral_constant

Member constants

value [static]	true if T has a virtual destructor , false otherwise (public static member constant)

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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>

Notes

If a class has a public virtual destructor, it can be derived from, and the derived object can be safely deleted through a pointer to the base object (C++FAQ Lite 20.7)

Example

#include <iostream>
#include <type_traits>
#include <string>
#include <stdexcept>
 
int main()
{
    std::cout << std::boolalpha
              << "std::string has a virtual destructor? "
              << std::has_virtual_destructor<std::string>::value << '\n'
              << "std::runtime_error has a virtual destructor? "
              << std::has_virtual_destructor<std::runtime_error>::value << '\n';
}

Output:

std::string has a virtual destructor? false
std::runtime_error has a virtual destructor? true

See also

is_destructible is_trivially_destructible is_nothrow_destructible (C++11) (C++11) (C++11)	checks if a type has a non-deleted destructor (class template)