https://en.cppreference.com/w/cpp/preprocessor/include https://en.cppreference.com/w/cpp/preprocessor/include __has_include and other compile-time checking wou

https://en.cppreference.com/w/cpp/preprocessor/include https://en.cppreference.com/w/cpp/preprocessor/include __has_include and other compile-time checking would work here (eg type_traits and enable_if)