Money is not like a unit in a system of units that has fixed relationships. It's not only time-varying but also contextual in other ways, eg. by locale, by fin

Money is not like a unit in a system of units that has fixed relationships. It's not only time-varying but also contextual in other ways, eg. by locale, by financial status or any number of other factors. This is a good analysis of how to represent money so that you can perform arithmetic and check for equality while accounting for contextual conversions: https://deque.blog/2017/08/17/a-study-of-4-money-class-designs-featuring-martin-fowler-kent-beck-and-ward-cunningham-implementations/ https://deque.blog/2017/08/17/a-study-of-4-money-class-desig...