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611 points LorenDB | 1 comments | | HN request time: 0s | 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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codedokode ◴[] No.43908939[source]
It's pretty difficult to have no panics, because many functions allocate memory and what are they supposed to do when there is no memory left? Also many functions use addition and what is one supposed to do in case of overflow?
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kllrnohj ◴[] No.43911645[source]
> Also many functions use addition and what is one supposed to do in case of overflow?

Honestly this is where you'd throw an exception. It's a shame Rust refuses to have them, they are absolutely perfect for things like this...

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1. brooke2k ◴[] No.43912152[source]
I'm confused by this, because a panic is essentially an exception. They can be thrown and caught (although it's extremely discouraged to do so).

The only place where it would be different is if you explicitly set panics to abort instead of unwind, but that's not default behavior.