I think you might have hit on the right answer: what about putting the arithmetic in a separate package? What if we had
- FixedPointWrappingArthmetic
- FixedPointSaturatingArithmetic
- FixedPointCheckedArithmetic
- FixedPointFloatArithmetic
and the user/developer just picked one? The main issue I foresee is we now need some mechanism of package exclusion: since they would all override Base operators, we can’t have ImageCore picking FixedPointFloatArithmetic while some other simultaneously-loaded package picks FixedPointCheckedArithmetic.
In the modern world all these could live in the same repository, so it would ensure they all remain closely coupled.
Splitting out the arithmetic and defining in a secondary package is technically type-piracy, but it’s that closely-coupled form of piracy that I’ve long argued has a valid place in the ecosystem.