[TheNorthman]

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.

[planetis]

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.

[TheNorthman]

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.

[frigid]

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.

[hayley-patton]

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>.

[planetis]

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