[Sebb767]

> That A and B can work together by default in Julia is really cool, but it also means that as you add new types and packages, you have a quadratically growing set of untested edges.

But as the authors example showed, they clearly can't work together - they just fail at runtime instead of at compile time.

Other languages have generics and interfaces to make stuff like this dynamically exchangeable. Sure, your code needs to be designed to support this, but it also means that the author explicitly thought about what they expect from their data structures. If they don't, you might suddenly find yourself violating implicit assumptions like arrays starting at 1.