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Comment by oconnor663 | Hacker News Reader

> Exceptions gives us a nice way to let problems bubble up to the surface, while also stating what the problem was, and where it occurred.

Work is ongoing on some of this, but there are popular libraries in Rust (like `anyhow`) that let you attach backtraces to regular errors, add context, etc. Propagating erros to callers is handled with the standard `?` operator, which means "short-circuit and return this if it was an error, otherwise give me the successful result". This has the benefit of making early exits explicit, without interrupting the visual flow of straight-line code.

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OK, I'm not into Rust. It just seems a bit too complicated :-)

The simple explanation is that Rust has an equivalent of Java-style exceptions of "throw here, handle elsewhere", but has a different syntax for this. Instead of try/catch, there's a `?` operator to return ("rethrow") the error to an outer scope. It's a better fit for Rust's use of a generic Result type, but overall its usage is similar to the checked exceptions in Java.

Because Rust uses the type-safe explicit Result/? approach for all non-bug failures in the program, the implicit panic (that behaves similarly to RuntimeException in Java) is reserved for assertion failures and crashes only.

`catch_unwind` is not guaranteed to work in Rust. There's a setting to disable it and always hard abort() the whole process on every panic. Rust is serious with panics being for programmer's bugs only, and not trivialities like "file not found".

Thanks for the explanation. I guess most languages need this feature i.e. fail anywhere below this call, then return the type error + where it occurred + a stack trace. I've even heard of people doing stuff like that in C, where they store the stack trace in a list they populate and return errors as part of the same struct, in order to have something similar to exceptions.

I have to say I really enjoyed Rust when it was in its infancy (version 0.1 - 0.2 or thereabouts), but have since fallen off. It used to be so simple and so clean, and unlike anything else. Today it's just way to complex for me :-)

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