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Re:All Algorithms Implemented in Rust by filiphorvat on Sunday August 21, 2022 @10:12PM (#32546560)
Linked list strikes again.
Re:All Algorithms Implemented in Rust by MuffinFlavored on Sunday August 21, 2022 @10:24PM (#32546617)
Is there not a way to do safe linked lists in Rust?
Re:All Algorithms Implemented in Rust by msdrigg on Sunday August 21, 2022 @10:41PM (#32546714)
You can do a singly linked list just fine.

But with a doubly linked list, who owns the memory to each node?

In reality, you can do a doubly linked list with something like `RefCell`.

See the famous blog post on linked lists in rust here: https://rust-unofficial.github.io/too-many-lists/fourth-buil...

Re:All Algorithms Implemented in Rust by jackpeterfletch on Monday August 22, 2022 @04:07AM (#32548636)
The borrow checker makes a doublily linked list difficult, from my understanding.

They're almost always a bad data structure to pick though, as the speed difference between being able to iterate a contiguous list, and even completely rebuild it, vs having to follow arbitrary pointers mean that the 'complexity' improvements of a linked list often become irrelevant.

------ Open Question)

I have this intuition that the borrow checker might enforce a way of working that fundamentally stops you from doing things that aren't _really_ compatible with the way a CPU actually works on the lowest level.

Is there any credence to that, and if so, is it happenstance, or is there some more fundamental reason?

Re:All Algorithms Implemented in Rust by kaba0 on Monday August 22, 2022 @11:00AM (#32552413)
> I have this intuition that the borrow checker might enforce a way of working that fundamentally stops you from doing things that aren't _really_ compatible with the way a CPU actually works on the lowest level.

No, I think you are reading too much into it. One is free to Box-allocate/pointer-chase on every line in Rust without any trouble. Sure, as other low level languages, rust also prefers/makes stack-allocation more ergonomic/the default, which is a quite cache-friendly way of operation but not even the stack is “native” in and of itself - it is just a frequently and extensively used part of the “heap”.

Re:All Algorithms Implemented in Rust by howinteresting on Sunday August 21, 2022 @11:57PM (#32547168)
Because of cache locality issues, linked lists are a bad data structure for almost all purposes. A plain old vector, or maybe a VecDeque, wins for almost all workloads.

For the few times they are useful (e.g. if you're writing lock-free algorithms, you want a hard upper bound O(1) append rather than just amortized O(1) append, or you don't have malloc available), Rust is a fine language to write them in. But also there are plenty of high-quality libraries on crates.io, so you probably won't have to write your own.