FreeBSD Manual Pages
std::has_vi...l_destructor(3) C++ Standard Libarystd::has_vi...l_destructor(3) NAME std::has_virtual_destructor - std::has_virtual_destructor Synopsis Defined in header <type_traits> template< class T > (since C++11) struct has_virtual_destructor; If T is a type with a virtual destructor, provides the member con- stant value equal to true. For any other type, value is false. If T is a non-union class type, T shall be a complete type; other- wise, the behavior is undefined. The behavior of a program that adds specializations for has_vir- tual_destructor or has_virtual_destructor_v (since C++17) is undefined. Template parameters T - a type to check Helper variable template template< class T > inline constexpr bool has_virtual_destructor_v = (since C++17) has_virtual_destructor<T>::value; Inherited from std::integral_constant Member constants value true if T has a virtual destructor , false otherwise [static] (public static member constant) Member functions operator bool converts the object to bool, returns value (public member function) operator() returns value (C++14) (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 (GotW #18). When true, is_polymorphic is true. Example // Run this code #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_er- ror>::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 checks if a type has a non-deleted de- structor (C++11) (class template) (C++11) (C++11) is_polymorphic checks if a type is a polymorphic class type (C++11) (class template) http://cppreference.com 2022.07.31 std::has_vi...l_destructor(3)
NAME | Synopsis | Template parameters | Member constants | Member functions | Member types | Notes | Example | Output: | See also
Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=std::has_virtual_destructor&sektion=3&manpath=FreeBSD+Ports+15.0>