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611 points LorenDB | 1 comments | | HN request time: 0.227s | source
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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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zozbot234 ◴[] No.43908381[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

This isn't really true since Rust has panics. It would be nice to have out-of-the-box support for a "no panics" subset of Rust, which would also make it easier to properly support linear (no auto-drop) types.

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alexeldeib ◴[] No.43908410[source]
that's kind of a thing with https://docs.rs/no-panic/latest/no_panic/ or no std and custom panic handlers.

not sure what the latest is in the space, if I recall there are some subtleties

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zozbot234 ◴[] No.43908453[source]
That's a neat hack, but it would be a lot nicer to have explicit support as part of the language.
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1. nicce ◴[] No.43909043[source]
The problem is with false positives. Even if you clearly see that some function will never panic (but it uses some feature which may panic), compiler might not always see that. If compiler says that there are no panics, then there are no panics, but is it enough to add as part of the language if you need to mostly avoid using features that might panic?