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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: 0s | source
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jpc0 ◴[06 May 25 18:22 UTC] No.43908110[source]▶
Amazing example of how easy it is to get sucked into the rust love. Really sincerely these are really annoying parts of C++.

The conversation function is more language issue. I don’t think there is a simple way of creating a rust equivalent version because C++ has implicit conversions. You could probably create a C++ style turbofish though, parse<uint32_t>([your string]) and have it throw or return std::expected. But you would need to implement that yourself, unless there is some stdlib version I don’t know of.

Don’t conflate language features with library features.

And -Wconversion might be useful for this but I haven’t personally tried it since what Matt is describing with explicit types is the accepted best practice.

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ujkiolp ◴[06 May 25 19:18 UTC] No.43908659[source]▶
meh, rust is still better cos it’s friendlier
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jpc0 ◴[06 May 25 19:27 UTC] No.43908743[source]▶
I don’t disagree. Rust learnt a ton from C++.

I have my gripes with rust, more it’s ecosystem and community that the core language though. I won’t ever say it’s a worse language than C++.

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noelnh ◴[06 May 25 22:33 UTC] No.43910343{3}[source]▶
Could you elaborate on those points, I'm genuinely curious? So far, I have found the Rust community to be immensely helpful, much more so than I experienced the C++ community. Granted, that's quite some time ago and might be at least partially caused by me asking fewer downright idiotic questions. But still, I'm interested in hearing about your experiences.
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1. jpc0 ◴[07 May 25 01:58 UTC] No.43911519{4}[source]▶
Rust libraries tend to over abstract and then need large refactors when those abstractions fall apart. When I’ve complained about it in the past I’ve been met with “You would need the abstraction eventually”. Maybe, but I’m also capable of building it myself it it gets to that.

Maybe that’s more of a bias with rust media stuff, seems to be going deeper into that rabbit hole though.

The community was at least, may still be, very sensitive to rust being criticised. I genuinely brought an example of a provably correct piece of code that the borrow checker wouldn’t accept, interior mutability problem. I was I should build a massive abstraction to avoid the problem and that I’m holding it wrong… Put me off the language for a few years, it shouldn’t have, I should have just ignored the people and continued on but we all get older and learn things.

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2. simonask ◴[07 May 25 08:24 UTC] No.43913356[source]▶
I think there's a bit of mismanaged expectations, combined with a community that, while generally helpful, suffers from a bit of fatigue from constantly dispelling myths and falsehoods about the language, often presented in bad faith.

My favorite is when Rust gets dragged into weird American "culture wars" - somehow, it's a "woke" language? (And somehow, that's a problem?)

But yeah, the language docs are pretty up front about the fact that the borrow checker sometimes rejects code that is provably fine, so it's a weird criticism. The nontrivial breakthrough was that Rust proved that a huge amount of nontrivial code can be written within the restrictions of the borrow checker, eliminating swaths of risk factors without a resource penalty.