FreeBSD Manual Pages
std::derived_from(3) C++ Standard Libary std::derived_from(3) NAME std::derived_from - std::derived_from Synopsis Defined in header <concepts> template< class Derived, class Base > concept derived_from = (since C++20) std::is_base_of_v<Base, Derived> && std::is_convertible_v<const volatile Derived*, const volatile Base*>; The concept derived_from<Derived, Base> is satisfied if and only if Base is a class type that is either Derived or a public and unambiguous base of De- rived, ignoring cv-qualifiers. Note that this behaviour is different to std::is_base_of when Base is a private or protected base of Derived. Example // Run this code #include <concepts> class A {}; class B: public A {}; class C: private A{}; int main() { // std::derived_from == true only for public inheritance or exact same class static_assert( std::derived_from<B, B> == true ); // same class: true static_assert( std::derived_from<int, int> == false ); // same primitive type: false static_assert( std::derived_from<B, A> == true ); // public inheritance: true static_assert( std::derived_from<C, A> == false ); // private inheritance: false // std::is_base_of == true also for private inheritance static_assert( std::is_base_of_v<B, B> == true ); // same class: true static_assert( std::is_base_of_v<int, int> == false ); // same primitive type: false static_assert( std::is_base_of_v<A, B> == true ); // public inheritance: true static_assert( std::is_base_of_v<A, C> == true ); // private inheritance: true } See also is_base_of checks if a type is derived from the other type (C++11) (class template) is_convertible is_nothrow_convertible checks if a type can be converted to the other type (C++11) (class template) (C++20) http://cppreference.com 2022.07.31 std::derived_from(3)
NAME | Synopsis | Example | See also
Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=std::derived_from&sektion=3&manpath=FreeBSD+Ports+15.0>