Header <variant> implementation status Reference Implementation : Cannot implement with language itself. Need compiler support. Used C++ N STL : Partially implemented with C++ N : Fully implemented with C++ N : Not yet implemented Features Standard Implemented in Includes <compare> Classes variant monostate bad_variant_access variant_size variant_size_v variant_alternative variant_alternative_t ss::hash<ss::variant> Constants variant_npos Functions visit holds_alternative ss::get(ss::variant) get_if operator== operator!= operator< operator<= operator> operator>= operator<=> ss::swap(ss::variant)