[SergeAx]

I got your point, and it's worth mentioning that there's that rare moment when Rust looks more readable than Go.

Concerning resulting API: isn't code generation solves a problem with interface objects and downcasting?

[chrismorgan]

I’m not sure what you’re asking. Generics are code generation (look into the term monomorphisation), just automatic and managed by the compiler for better convenience than manual code generation by other means, and type safe for better correctness and efficiency than interface objects and downcasting.