rosettaboy VS hashbrown

As somebody who has written the same gameboy emulator in C++, Rust, and Zig (as well as C, Go, Nim, PHP, and Python) - I have yet to find a place where language affected emulation correctness.

Gameboy audio is kind of a pain in the ass (at least compared to CPU, which is fairly easy, and GPU, which is easy to get "good enough” if you don’t care about things like palette colours being swapped mid-scanline) - and some languages take more or less code to do the same thing (eg languages which allow one block of memory to be interpreted in several different ways concurrently will make the “interpret audio RAM as a bunch of registers” code much shorter with less copying) - but in my case at least, each one of my implementations actually has the same audio distortions, presumably because I’m misreading some part of the hardware spec :P

https://github.com/shish/rosettaboy/

(Also yes, the zig version is currently failing because every time I look at it the build system has had breaking changes...)

Niceness is subjective, but Nim is just as valid an addition to that group. Nim compiles to C and has had an --os=standalone mode for like 10 years from its git history, and as mentioned else-thread (https://news.ycombinator.com/item?id=36506087) can be used for Linux kernel modules. Multiple people have written "stub OSes" in it (https://github.com/dom96/nimkernel & further along https://github.com/khaledh/axiom).

While it can use clang as a backend, Nim does not rely upon LLVM support like Zig or Rust (pre-gcc-rust working). Use on embedded devices is fairly popular: https://forum.nim-lang.org/search?q=embedded (or web search).

Latency-wise, for a time, video game programming was a perceived "adoption niche" or maybe "hook" for Nim and games often have stringent frame rendering deadlines. If you are interested in video games, you might appreciate https://github.com/shish/rosettaboy which covers all but Ada in your list with Nim being fastest (on one CPU/version/compiler/etc). Note, however, that cross-PL comparisons are often done by those with much "porting energy" but limited familiarity with any but a few of the PLs. A better way to view it is that "Nim responds well to optimization effort" (like C/Ada/C++/Rust/Zig).

https://github.com/shish/rosettaboy

The same gameboy emulator rewritten in C++, Go, Nim, PHP, Cython, Python, Rust, and Zig (and WIP typescript); mostly to teach myself the languages and to compare and contrast their idioms.

Also, when taken with a very large grain of salt, usable as a language benchmark (As with all benchmarks, there are lots of caveats - but as far as I’m aware this is unique in being “the same code in multiple languages” and “several thousand lines of code”):

  $ ./utils/bench.py

Looks very polished, but major disappointment that it's not showcasing OCaml as part of RosettaBoy (https://github.com/shish/rosettaboy)

I’m working on it :) https://github.com/shish/rosettaboy

(Ok it’s 5-10k lines rather than a million, but it’s non-trivial enough that the differences between languages are noticable)

That's because you're looking at a wrapper around the actual implementation (which lives in an external package). Notice "use hashbrown::hash_map as base;" at the top.

There's far more unsafe there: https://github.com/rust-lang/hashbrown/blob/f2e62124cd947b5e...

You might want to check out how popular ecosystem crates do some of these things. Particularly relevant to you are probably crates providing collections, such as smallvec, hashbrown, or indexmap.

https://github.com/topics/swisstable

rust-lang/hashbrown: https://github.com/rust-lang/hashbrown

CuPy has array but not yet hashmaps, or (GPU) SIMD FWICS?

NumPy does SIMD:

Thanks, great point indeed. I am looking into this https://github.com/rust-lang/hashbrown

The way I think about it -- rather naively, I suppose -- is that I care more about the references cells make to each other than the actual grid of cells displayed on a table. The latter feels more like a "view" of the data than an actual data structure?

This also seems to align with the relative priority of (sorted from highest to lowest): figuring out the order of evaluation, calculating those evaluations, and finally displaying the results of the evaluation

updated std's hashbrown dependency to 0.14 which contains some optimizations

The std hashmap is actually very fast and uses state of the art hashmap design, namely because it's implemented by hashbrown

I believe Rust uses hashbrown as the underlying implementation now. This just calculates the number of buckets based on the number of items requested:

https://github.com/rust-lang/hashbrown/blob/009969a860290849...

Is it really the case that rehashing can guarantee that the number of buckets allocated will be sufficient for any given set of keys? In principle you could fail to rehash in a way that reduces collisions after k attempted rehashings.

For example, since the hashbrown crate is marked with #![no_std], it can be used as a dependency for the standard library.

To implement something that cannot be expressed in safe Rust, or at least cannot be expressed succinctly in safe Rust, like fundamental datastructures. The hashbrown crate contains a lot of unsafe code, but it's such high quality that it's now the backing implementation for std::collections::HashMap.