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The borrowchecker is what I like the least about Rust

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Re: The borrowchecker is what I like the least about Rust

#101

Post by estebank »

pyrale wrote: post #94
mr_00ff00 wrote: post #26

Earlier quoted context omitted.

This is also somewhat backed up by the fact that OCaml (to my understanding) is basically GC Rust without a borrow checker, and yet it’s basically a hobby language.

> and yet it’s basically a hobby language. The difference between academia languages such as ocaml or haskell and industry languages such as Java or C# is hundreds of millions of dollar in advertising. It's not limited to the academy: plenty of languages from other horizons failed, that weren't backed by companies with a vested interest in you using their language. You should probably not infer too much from a langua…

You're making it sound like the success of a language is determined purely by its advertising budget by pointing at languages that had financial backing, which disregards that financial backing allows for more resources to solve technical problems. Java and C# have excellent developer tools which wouldn't have existed in their current state without lots of money being thrown around, and the languages' adoption trajectory wouldn't have looked the way they did if their tooling hasn't been as good as it was. A new language with 3 people behind it can come up with great ideas and excellent execution, but if you can't get enough of the scaffolding built in order to gain development momentum and adoption, then it is very hard to become mainstream, and money can help with that.

Re: The borrowchecker is what I like the least about Rust

#102

Post by forrestthewoods »

lblume wrote: post #87
forrestthewoods wrote: post #22

One day I will write a blog post called “The Rust borrow checker is overrated, kinda”. The borrow checker is certainly Rust’s claim to fame. And a critical reason why the language got popular and grew. But it’s probably not in my Top 10 favorite things about using Rust. And if Rust as it exists today existed without the borrow checker it’d be a great programming experience. Arguably even better than with the borrow c…

> No bumpalo doesn't count. Mind explaining why? I have made good experiences with bumpalo.

Everytime I try to use bumpalo I get frustrated, give up, and fallback to RAII allocation bullshit.

My last attempt is I had a text file with a custom DSL. Pretend it’s JSON. I was parsing this into a collection of nodes. I wanted to dump the file into an arena. And then have all the nodes have &str living in and tied to the arena. I wanted zero unnecessary copies. This is trivially safe code.

I’m sure it’s possible. But it required an ungodly amount of ugly lifetime 'a lifetime markers and I eventually hit a wall where I simply could not get it to compile. It’s been awhile so I forget the details.

I love Rust. But you really really have to embrace the RAII or your life is hell.

Re: The borrowchecker is what I like the least about Rust

#103

Post by mavelikara »

mr_00ff00 wrote: post #26
eigenspace wrote: post #11

I don't use Rust much, but I agree with the thrust of the article. However, I do think that the borrowchecker is the only reason Rust actually caught on. In my opinion, it's really hard for a new language to succeed unless you can point to something and say "You literally can't do this in your language" Without something like that, I think it just would have been impossible for Rust to gain enough momentum, and also…

This is also somewhat backed up by the fact that OCaml (to my understanding) is basically GC Rust without a borrow checker, and yet it’s basically a hobby language.

The first version of Rust compiler, I think, was written in OCaml.

Re: The borrowchecker is what I like the least about Rust

#104

Post by forrestthewoods »

bobajeff wrote: post #89
forrestthewoods wrote: post #22

One day I will write a blog post called “The Rust borrow checker is overrated, kinda”. The borrow checker is certainly Rust’s claim to fame. And a critical reason why the language got popular and grew. But it’s probably not in my Top 10 favorite things about using Rust. And if Rust as it exists today existed without the borrow checker it’d be a great programming experience. Arguably even better than with the borrow c…

This is something I've been thinking about lately. I do think memory safety is an important trait that rust has over c and other languages with manual memory management. However, I think Rust also has other attractive features that those older languages don't have: * a very nice package manager * Libraries written in it tend to be more modular and composable. * You can more confidently compile projects without worryi…

Agree on all points

Re: The borrowchecker is what I like the least about Rust

#105

Post by ChadNauseam »

> [The pain of the borrow checker is felt] when your existing project requires a small modification to ownership structure, and the borrowchecker then refuses to compile your code. Then, once you pull at the tiny loose fiber in your code's fabric, you find you have to unspool half your code before the borrowchecker is satisfied.

Probably I just haven't been writing very "advanced" rust programs in the sense of doing complicated things that require advanced usages of lifetimes and references. But having written rust professionally for 3 years now, I haven't encountered this once. Just putting this out there as another data point.

Of course, partial borrows would make things nicer. So would polonius (which I believe is supposed to resolve the "famous" issue the post mentions, and maybe allow self-referential structs a long way down the road). But it's very rare that I encounter a situation where I actually need these. (example: a much more common need for me is more powerful consteval.)

Before writing Rust professionally, I wrote OCaml professionally. To people who wish for "rust, but with a garbage collector", I suggest you use OCaml! The languages are extremely similar.

Re: The borrowchecker is what I like the least about Rust

#106

Post by [deleted] »

mr_00ff00 wrote: post #42
dismalaf wrote: post #31

Earlier quoted context omitted.

Hobby language? Plenty of commercial and important software has been written in OCaml. Hell, the early versions of the Rust compiler were written in OCaml...

Maybe I’m wrong, but I only really know of Jane Street for OCaml, meanwhile FAANG all has at least some rust code. Also I would argue the rust compiler started as a hobby project

[deleted]

Re: The borrowchecker is what I like the least about Rust

#107

Post by spacechild1 »

tnh wrote: post #58
majormajor wrote: post #10

Earlier quoted context omitted.

This seems to be a golden rule of many languages? `return 3` in a function with a signature that says it's going to return a string is going to fail in a lot of places, especially once you exclude bolted-on-after-the-fact type hinting like what Python has. It's easier to "abuse" in some languages with casts, and of course borrow checking is not common, but it also seems like just "typed function signatures 101". Are…

In C++, the signature of a function template doesn't necessarily tell you what types you can successfully call it with, nor what the return type is. Much analysis is delayed until all templates are instantiated, with famously terrible consequences for error messages, compile times, and tools like IDEs and linters. By contrast, rust's monomorphization achieves many of the same goals, but is less of a headache to use b…

> In C++, the signature of a function template doesn't necessarily tell you what types you can successfully call it with, nor what the return type is.

That's the whole point of Concepts, though.

Re: The borrowchecker is what I like the least about Rust

#108

Post by School-Cotton »

littlestymaar wrote: post #60
School-Cotton wrote: post #35

Earlier quoted context omitted.

I think you are misunderstanding what Copy means, and perhaps confusing it with Clone. A type being Copy has no effect on what machine code is emitted when you write "x = y". In either case, it is moved by copying the bit pattern. The only thing that changes if the type is Copy is that after executing that line, you are still allowed to use y.

I'm not misunderstanding. Ore confusing the two. Copy: Clone . Yes when an item is Copy-ed, you are still allowed to use it, but it means that you now have two independent copies of the same thing, and you may edit one, then use the other, and be surprised that it hasn't been updated. (When I briefly worked with Go, junior developers with mostly JavaScript or Python experience would fall into this trap all the time )…

Got it. Indeed, I misunderstood your point. I agree with you now that you clarified.

Re: The borrowchecker is what I like the least about Rust

#109

Post by amelius »

mr_00ff00 wrote: post #26
eigenspace wrote: post #11

I don't use Rust much, but I agree with the thrust of the article. However, I do think that the borrowchecker is the only reason Rust actually caught on. In my opinion, it's really hard for a new language to succeed unless you can point to something and say "You literally can't do this in your language" Without something like that, I think it just would have been impossible for Rust to gain enough momentum, and also…

This is also somewhat backed up by the fact that OCaml (to my understanding) is basically GC Rust without a borrow checker, and yet it’s basically a hobby language.

Idiomatic programming in a functional language requires garbage collection. There is a reason languages like OCaml and Haskell have a garbage collector. Without it, programming in these languages would be completely different.

If you look at it from that perspective, then Rust is the hobby language.

Re: The borrowchecker is what I like the least about Rust

#110

Post by creata »

pyrale wrote: post #95
creata wrote: post #48

Earlier quoted context omitted.

I had the impression that SML was more popular in academia, and OCaml in industry. Old but funny comparison: http://adam.chlipala.net/mlcomp/

SML was a generation before ocaml. I would say the two languages from the same generation that competed for academia's mindshare were ocaml and Haskell.

Timeline-wise, sure, but I was referring to their present-day use.
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