While being a very modest piece of code in and of itself, I believe this offers a significant opportunity that both D compilers and user defined types can exploit.
I did this in C/C++ a while ago, out of which I have forgotten most of it :)
https://github.com/nordlow/justcxx/blob/master/sadd.h https://github.com/nordlow/justcxx/blob/master/ssub.h https://github.com/nordlow/justcxx/blob/master/smul.h Tests are here: https://github.com/nordlow/justcxx/blob/master/t_ranged_and_saturated.cpp Maybe there's something more here that could give further ideas. Pick what you want.