something very interesting that only swift seems to have implemented (please correct me: I wanna know) is the nesting of enums. Enum cases can reference other types which allows for exiting stuff, as shown in my article: https://decodemeester.medium.com/khipu-rapid-and-sustainable-software-creation-in-swift-using-engineering-and-science-principles-312a933cce57?sk=8359f48cc06571e53de156db8cbc005c