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What it feels like when Rust saves your bacon

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Re: What it feels like when Rust saves your bacon

#181

Post by jesse__ »

Yoric wrote: post #123
jesse__ wrote: post #95

Earlier quoted context omitted.

I'd venture that the development slowdown from using rust is closer to 50% than 5%. Even just compile times probably slow down that much, not to mention you have to write (sometimes) as much as 10x code to express yourself. The specific exercise I have in mind is a lockless thread queue. < 20 lines in C .. ~200 lines in Rust.

My anecdotal experience is the opposite. I write code much faster in Rust than in C++. Part of it is thanks to the type system – fewer opportunities for dev errors means that I can produce code that is more concise, spends less time handling runtime errors because I can have static guarantees that they have already been handled somewhere, etc. Part of it is #[derive(...)], great documentation, Cargo and other QoL com…

Fair enough. I can imagine if you largely write code that plays nice with the compiler it could be faster. That just hasn't been my experience.

Re: What it feels like when Rust saves your bacon

#182

Post by jesse__ »

pkulak wrote: post #108
jesse__ wrote: post #95

Earlier quoted context omitted.

I'd venture that the development slowdown from using rust is closer to 50% than 5%. Even just compile times probably slow down that much, not to mention you have to write (sometimes) as much as 10x code to express yourself. The specific exercise I have in mind is a lockless thread queue. < 20 lines in C .. ~200 lines in Rust.

A lockless thread queue (not entirely sure what that would be, sorry; a queue in front of a pool?) seems like the kind of low-level library that could be written with liberal use of unsafe. No need to flagellate yourself on the altar of compile-time safety.

Then why would I use rust in the first place?

Re: What it feels like when Rust saves your bacon

#183

Post by jesse__ »

ttfkam wrote: post #178
jackmott42 wrote: post #100

Earlier quoted context omitted.

I'm sure there is a ton of variance. I have done some Rust projects where I run into absolutely no safety complaints from Rust because it just isn't the kind of code that does anything the borrow checker cares about. For those development time ends up typically faster than C/C++ due to various syntax and tooling niceties. Other projects will really get into domains where you have to work hard to satisfy the borrow ch…

And you're running at least one static analysis tool and a linter on your C++ code too, right? You're not just deploying the C++ compiler output as-is, right? Those take time to run too and should absolutely be added to the compile time metrics when comparing against "cargo build".

On a personal project I run 2 metaprogramming passes, compile the entire project (~2m LoC) _twice_ and run the entire test suite in I don't run a linter because I hate them, and my metaprogramming passes do a bit of extra static checking clang doesn't. I occationally run extra static tools (valgrind et. al) but they're painfully slow and very rarely catch anything.

Re: What it feels like when Rust saves your bacon

#184

Post by kaba0 »

jnordwick wrote: post #165
kajaktum wrote: post #104

Earlier quoted context omitted.

>The specific exercise I have in mind is a lockless thread queue. Do they have an equivalent API? Rust does have a hard time explaining very, very low level stuff that you'd have to do unsafe and various magicks. But once you get the unsafe details right, the consumer API for them tends to be extremely rigid and fool proof.

> Rust does have a hard time explaining very, very low level stuff A little odd for a supposed system langauge

But it is just not true. Rust has a hard time writing algorithms where objects don’t have a singular owner. That’s all, it is not low level stuff. It for example has proper SIMD support, while the supposedly low level c doesn’t.

Re: What it feels like when Rust saves your bacon

#185

Post by kaba0 »

jesse__ wrote: post #183
ttfkam wrote: post #178

Earlier quoted context omitted.

And you're running at least one static analysis tool and a linter on your C++ code too, right? You're not just deploying the C++ compiler output as-is, right? Those take time to run too and should absolutely be added to the compile time metrics when comparing against "cargo build".

On a personal project I run 2 metaprogramming passes, compile the entire project (~2m LoC) _twice_ and run the entire test suite in I don't run a linter because I hate them, and my metaprogramming passes do a bit of extra static checking clang doesn't. I occationally run extra static tools (valgrind et. al) but they're painfully slow and very rarely catch anything.

Rust in incremental build mode is not slow at all, I really don’t see why people say so.

Re: What it feels like when Rust saves your bacon

#186

Post by phendrenad2 »

ttfkam wrote: post #180
phendrenad2 wrote: post #160

Earlier quoted context omitted.

Nope. In my experience, Rust saves you from very common obvious errors that junior programmers make, certainly not 10x programmers who have been writing C for a long time. It's great when you're starting out (which is why it's massively popular with new graduates or people who are just learning to program), but at some point it's questionable if the hand-holding Rust gives you is worth the extra development time over…

Yep, all those kernel, driver, and database devs out there are all junior devs just starting out. No way anyone with decades of experience will introduce a remote exploit or crashing bug in their C programs and libraries. Never happens. No CVEs to see here! Move along! /s

Why do you think this is a valid argument? Are you saying there are no junior devs working on databases, kernels, drivers? What evidence do you propose to back up that astounding claim?

Re: What it feels like when Rust saves your bacon

#187

Post by ColonelPhantom »

jesse__ wrote: post #182
pkulak wrote: post #108

Earlier quoted context omitted.

A lockless thread queue (not entirely sure what that would be, sorry; a queue in front of a pool?) seems like the kind of low-level library that could be written with liberal use of unsafe. No need to flagellate yourself on the altar of compile-time safety.

Then why would I use rust in the first place?

So that you can write "primitives" such as a queue in unsafe, and assuming it is correct, it is not possible to introduce bugs from other code.

Also, things like queues tend to be implemented in either the stdlib or a very popular library. So they are very well tested and likely to be widely reviewed.

Re: What it feels like when Rust saves your bacon

#188

Post by riking »

strictfp wrote: post #161
jandrewrogers wrote: post #153

Earlier quoted context omitted.

Can you give some examples of what you mean? I use static polymorphism in C++ routinely and haven't felt particularly limited by it.

Sure. I guess template-based polymorphism is alright for code dispatch. But if you want to store the different types of objects involved you have limited choices. There's no straight-forward support for sum types. std::variant is fairly new, has a cumbersome API, and is quite slow (ballpark the same as virtual calls). There's no support for methods on enums nor anything for customizing the fields of different enum co…

"hmm, you call it an 'enum class' yet somehow I cannot define methods on it"

Re: What it feels like when Rust saves your bacon

#189

Post by TonyYayo »

axilmar wrote: post #56

Rust is undoubtedly a step forward in correctness, but boy, the article's code is so thick that for me, that I am a C++ programmer, is almost unreadable, especially for a quick reading... I skipped all the code and only read the text. I got to the point where it mentions that the language prevented them from storing a pointer to a stack object in a heap object, and that's really great, but boy oh boy, the code presen…

Hello Axilmar. Incase you were unaware, a strong push for a DFUW relaunch is making strides, and team members are interested in having some discussion with you that include a possibility of being hired in some capacity. You can contact me on Discord as TonY#2011 and I can put you on direct contact with investors for more details. Hope to hear from you soon!

Re: What it feels like when Rust saves your bacon

#190

Post by hardex »

phendrenad2 wrote: post #160
bestouff wrote: post #22

Earlier quoted context omitted.

Yeah no. In my experience, when several people commit to a common C/C++ codebase this kind of issue become really exhausting when it happens more than once, and the symptoms may be so subtle it's a bitch to debug. Rust lowers your mental load. You spend more time being creative and way less time debugging "obvious" (or not) mechanical problems (reference not-on-stack-anymore variables, use-after-free, concurrent writ…

Nope. In my experience, Rust saves you from very common obvious errors that junior programmers make, certainly not 10x programmers who have been writing C for a long time. It's great when you're starting out (which is why it's massively popular with new graduates or people who are just learning to program), but at some point it's questionable if the hand-holding Rust gives you is worth the extra development time over…

For the unironic use of "10x programmer", I'm hereby sentencing you to death.
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