Nice! Reminds me of the ergonomics of Rebol's money type:

https://www.rebol.com/docs/core23/rebolcore-16.html#section-...

> $100 + 11 $111.00

> $10 / .50 $20.00

In general, Rebol's type system was very expressive. Would love to see more libraries like this provide that type of experience.