std::has_virtual_destructor

From Cppreference

Defined in header `<type_traits>`

template< class T > struct has_virtual_destructor;		(C++11 feature)

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`	true if `T` has a virtual destructor , 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] 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)

[edit] 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

[edit] 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)