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Comment by jasfi | Hacker News Reader

It's great the memory-safe languages that don't sacrifice performance are growing in popularity. But I must ask, what does Rust do better than Nim?

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Nim, while providing the same memory safety as Rust, doesn't do so without overhead. So Nim very expressly sacrifices performance for safety.

In rust, for example, it's possible to safely share data between threads without incurring costs of a garbage collector. Nim uses a different GC for each thread, so it naturally increases costs on a per-thread basis.

No more GC in Nim now there is an optional cycle collector https://nim-lang.org/blog/2020/12/08/introducing-orc.html it also offers experimental view types.

I was sort of vaguely aware of this but thank you for pointing it out! I think the point still stands, and that reference counting like this is just a different kind of garbage collection.

It's not exactly like that there is cursor inference and copy elision. But ok...

It certainly adds (some, not many thanks to static analysis) runtime checks, but it's also fairly distinguished from typical tracing garbage collection by being deterministic. I believe ARC/ORC also works with a shared heap via "isolated" data.

That's correct; there are two chapters of the GC Handbook on reference counting, and ye olde unified theory of garbage collection <https://dl.acm.org/doi/10.1145/1028976.1028982>.

It's been a few years since I've used Nim, but outside of the language itself, the tooling around Rust is absolutely incredible. Rust Analyzer, Clippy, Cargo, etc.

Network effects are big at this point. Nim doesn't have a userbase or ecosystem like Rust.

> what does Rust do better than Nim?

I can install Rust, for one thing (I’m on an M1 mac; trying the three main nim installers, one gives me an out of date version, one gives me the x86 version, and one segfaults)

Also Rust’s error messages and standard library documentation are way more helpful

Also Rust runs nearly twice as fast

(I do like the nim language, but no more or less than I like the rust language; tooling makes a big difference though)

For me (and inv2004) Nim, runs faster than Rust on your RosettaBoy project.. But perf usually depends on an awful lot of territory that is routinely unexplored before conclusions are bandied about.

The Nim installation & tooling experience unfortunately can be rough. OTOH, it has like <1% the funding/exposure. Also, I find the "100s of packages dependencies" for any non-trivial Rust program to be pretty awful, as well as reading other people's Rust code (a point made more salient by all the deps).

Anyway, there are many dimensions/axes by which to evaluate most things in life and usually no objective way to weight/combine them into a single overall score. So, it's often good to keep an open mind. (Not saying you don't do so personally!)

> For me (and inv2004) Nim, runs faster than Rust on your RosettaBoy project

I didn’t spot that it had improved that much; I guess I need to hurry up and brute-force my way past the installer issues to try it out :D

If it helps, I almost always just git clone & compile Nim from source myself.. takes just a couple minutes. Never tried it on an M1, though.

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