The C++ standard library std::basic_regex attempts to do this by exposing a templated class over a custom character type. https://en.cppreference.com/w/cpp/rege

The C++ standard library std::basic_regex attempts to do this by exposing a templated class over a custom character type. https://en.cppreference.com/w/cpp/regex/basic_regex https://en.cppreference.com/w/cpp/regex/basic_regex You can provide your own trait class to define things for your custom "characters". Unfortunately performance goes out of the window. And it's likely to work as well as storing arbitrary non-character things into a custom std::basic_string.