alt Hacker NewsI agree that the rust community frowns a little too much on the use of Arc/Cloning/Box. If you use swift, everything is ref counted, why subject yourself to so much pain for marginal gain.
Tutorials and books should be more open about that, instead of pushing complex lifetime hacks etc., also show the safe and easy ways.
The article gives Java a worse devx rank than Go and I can't agree. Java is at least on par with go in every aspect of devx, and better in IDE support, expressiveness, and dependency mgmt.
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Pretty sure by devx they mean something like syntax ergonomics. Because otherwise rust's devx first class (cargo, clippy, crates.io) so kind of a nonstandard definition.
I think it's fair to say Java's "syntax ergonomics" are a little below the rest / somewhat manual like rust or C++ by default.
There is a significant chunk of the rust community that encourages the use of Arc, clone and Box outside of the hot path. Perhaps you're just hooked up with the wrong part of the community?
You're likely to get more pushback when creating public crates: you don't know if it's going to be someone else's hot path.
But the internal code for pretty much any major rust shop contains a lot more Arc, Box and clone than external code.
I am not sure the community frowns on these. In fact I use those in almost every Rust code I write. The point is that i can grep for those because Rust does not do it in a hidden way.
> I agree that the rust community frowns a little too much on the use of Arc/Cloning/Box
As usual, this depends heavily on what you do. I had written a program where Arc reference counting was 25 % of the runtime. All from a single instance as well. I refactored to use borrows and annotated relevant structs with lifetimes. This also enabled additional optimisation where I could also avoid some copies, and in total I saved around 36% of the total runtime compared to before.
The reason Arc was so expensive here is likely that the reference count was contended, so the cacheline was bouncing back and forth between the cores that ran the threads in the threadpool working on the task.
In conclusion, neither extreme is correct. Often Arc is fine, sometimes it really isn't. And the only way to know is to profile. Always profile, humans are terrible at predicting performance.
(And to quite a few people, coming up with ways to avoid Arc/clone/Box, etc can be fun, so there is that too. If you don't enjoy that, then don't participate in that hobby.)