[sixbrx]

> That Rust and Swift require explicitly bubbling error values should be a point in favour of checked exceptions

I thought the explicit bubbling was the nicest thing about error handling in Rust. It's usually just a single character ('?') that the editor can easily highlight, and nicely indicates where the operations are that might fail.

I'd add that checked exceptions don't play nicely with general functional/stream operations like "map" which is why Java went with unchecked exceptions for their streams api in Java 8. Rust on the other hand can handle interior failures in such functions nicely, promoting them to a single overall failure easily via collect(), using the blanket FromIterator<Result<A, E>> implementation for Result<V, E>.

[masklinn]

> I'd add that checked exceptions don't play nicely with general functional/stream operations like "map" which is why Java went with unchecked exceptions for their streams api in Java 8. Rust on the other hand can handle interior failures in such functions nicely, promoting them to a single overall failure easily via collect(), using the blanket FromIterator<Result<A, E>> implementation for Result<V, E>.

And Swift has a `rethrows` marker to transitively do whatever a callback does, it's equivalent to "throws" if the callback throws, and to nothing if it does not. So e.g. `map(_ fn: (A) throws -> B) rethrows` will throw if the callback it is provided throws, and not throw if the callback doesn't throw.