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dvratil ◴[] No.43908097[source]
The one thing that sold me on Rust (going from C++) was that there is a single way errors are propagated: the Result type. No need to bother with exceptions, functions returning bool, functions returning 0 on success, functions returning 0 on error, functions returning -1 on error, functions returning negative errno on error, functions taking optional pointer to bool to indicate error (optionally), functions taking reference to std::error_code to set an error (and having an overload with the same name that throws an exception on error if you forget to pass the std::error_code)...I understand there's 30 years of history, but it still is annoying, that even the standard library is not consistent (or striving for consistency).

Then you top it on with `?` shortcut and the functional interface of Result and suddenly error handling becomes fun and easy to deal with, rather than just "return false" with a "TODO: figure out error handling".

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mdf ◴[] No.43908219[source]
Generally, I agree the situation with errors is much better in Rust in the ways you describe. But, there are also panics which you can catch_unwind[1], set_hook[2] for, define a #[panic_handler][3] for, etc.

[1] https://doc.rust-lang.org/std/panic/fn.catch_unwind.html

[2] https://doc.rust-lang.org/std/panic/fn.set_hook.html

[3] https://doc.rust-lang.org/nomicon/panic-handler.html

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1. ekidd ◴[] No.43908789[source]
Yeah, in anything but heavily multi-threaded servers, it's usually best to immediately crash on a panic. Panics don't mean "a normal error occurred", they mean, "This program is cursed and our fundamental assumptions are wrong." So it's normal for a unit test harness to catch panics. And you may occasionally catch them and kill an entire client connection, sort of the way Erlang handles major failures. But most programs should just exit immediately.