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Comment by roblabla | Hacker News Reader

The actual context of your quote:

> Just so we're totally 100% clear: I hate linked lists. With a passion. Linked lists are terrible data structures. Now of course there's several great use cases for a linked list: > > - You're writing a kernel/embedded thing and want to use an intrusive list.

So I’ve got no clue what you’re railing about. The project specifically acknowledges that there is a need in kerneldev for those data structures.

I’m a kernel dev using Rust for my kernel. I use both intrusive linked list and growable vectors in it. The thing is, the sentiment expressed in the article really resonates in me: in most cases, growable vectors are a better choice, performance-wise.

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The quote that the GP is talking about is included below, which copy/pasted from the project page, and the Mumble mumble line is the heading for a paragraph:

‘’’Mumble mumble kernel embedded something something intrusive.

It's niche. You're talking about a situation where you're not even using your language's runtime. Is that not a red flag that you're doing something strange?

It's also wildly unsafe.’’’

Also, prior to this author claims the following, where the first line also a section heading:

‘’’ I can't afford amortization

You've already entered a pretty niche space’’’

These fiat rulings based on one an authors generalization of what is ‘niche’ are what I assume GP was commenting on. These are the kinds of dismissals that some developers take issue with, as GP states.

Kernel development is niche. Most of the time you don’t need linked lists.

When all you have is Rust everything starts to look like adjustable array.

What’s an adjustable array? A vector?

A vector is a one-dimensional array. Adjustable arrays can have arbitrary number of dimensions, although am not sure if it's a thing in Rust.

That just sounds like a graph.

How in the heaven an array can sound like a graph?

Sounds like one to me.

I've spent years programming rust and I'm not sure what you mean. Do you mean arrays of tuples, or nested arrays?

I mean a multi-dimensional array.

Thanks! Why does everything look like a multi-dimensional array for you in rust?

An array (an ADT) can be arbitrary dimensional, with one-dimensional case often called vector (and two-dimensional called matrix). An array can also be adjustable, both in one and multi-dimension variants.

So a vector can be both adjustable and non adjustable, and some language do have both versions. Some language have adjustable one-dimensional array/vector as the only dynamic aggregate/ordered datatype.

And to answer the post I replied to originally, a vector in rust is a one-dimensional adjustable array. To answer your question above, no that's not what I meant, sorry for not being clear enough from the beginning.

Thanks for clarifying.

I think we're just using different definitions. The only real definition of an array I've encountered in work and school is that it's just a one dimensional collection of elements, usually of static size. A vector depending on context is usually the same thing as an array but you conveniently change the size dynamically. Lists can whatever you need it to be given the context, just needs to be sequential.

Of course you can represent higher dimension structures by linearizing indices (x + row_size * y, etc).

I think people are getting confused as most don't consider arrays to be arbitrarily dimensional without some scheme.

Completely off topic but you've reminded me of this great article: https://hypirion.com/musings/understanding-persistent-vector...

Rust has singly linked, double linked ( in its minimal std library) and intrusive linked lists - all with APIs that guarantee a lack of memory errors and data races at compiler. I don’t know any good kernel developer that wouldn’t like those guarantees and I work in the Linux kernel professionally full time.

If you can't tell when to break or not break rules then maybe you are not a kernel developer? It's almost like a King only following his own laws instead of being the one making them. Why are you a King again?

(Had to edit in a quote to what I was replying to because you fixed the original):

> The actual context of your fake quote:

Good grief, that was a verbatim quote! Here's a link to the exact text I quoted:

https://rust-unofficial.github.io/too-many-lists/#mumble-mum...

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