Well, it is bad to have error() do UB. It was slightly improved in C++26 under hardening: https://en.cppreference.com/w/cpp/utility/expected/error.html https:

Well, it is bad to have error() do UB. It was slightly improved in C++26 under hardening: https://en.cppreference.com/w/cpp/utility/expected/error.html https://en.cppreference.com/w/cpp/utility/expected/error.htm...