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Matt Godbolt sold me on Rust by showing me C++

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611 points LorenDB | 2 comments | 06 May 25 17:51 UTC | HN request time: 0.4s | source
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dvratil ◴[06 May 25 18:20 UTC] 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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1. divan ◴[08 May 25 09:42 UTC] No.43924618[source]▶
Convention-wise Go is even better. On the one hand, there is zero magic in error handling ("Errors are values" and interface type 'error' is nothing special), on the other hand it's kind of a convention (slightly enforced by linters) that functions that return errors use this type and it's the last return parameter.

Nothing prevents people from doing their own way (error int codes, bool handling, Result types, etc, panic), but it's just an easiest way that handles well 99% of the error handling cases, so it sticks and gives a nice feeling of predictability of error handling patterns in Go codebases.

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2. ttfkam ◴[08 May 25 15:15 UTC] No.43926895[source]▶
It's also highly dependent upon the team's skill and diligence. You can easily ignore errors and skip error handling in Go with predictably hilarious results.

In Rust, you can't just skip error handling. You have to proactively do something generally unwise (and highly visible!) like call .unwrap() or you have to actually handle the error condition.

Go still relies on goodwill and a good night's sleep. The Rust compiler will guard against laziness and sleep deprivation, because ultimately programming languages are about people, not the computers.