transit-lang-cmp VS deno_std

> The axum::debug_handler macro is invaluable to debug type errors (there's some with axum too), like for example, accidentally having a non-Send type slip in.

Heh, yeah. For my recent project where I explored implementing the same little app in a few different languages[0], I chose Axum for the rust version.

The whole "extractor" system was pretty magical, and when I had this exact issue (non-Send argument), the compiler error was totally useless. I did see the docs about adding this extra macro crate for error messages but it seemed like a bit of a red flag that the framework was going against the grain of the language. Still, on the whole, I did enjoy working with Axum.

[0] https://github.com/losvedir/transit-lang-cmp

This is great! Just pushed up a commit that uses it and updated the benchmarks[0]. I'm seeing a 1.6X - 2X improvement in overall performance. Not bad for a drop-in replacement. And since it's based on serde, I trust it, and I feel like trying out a different JSON library is within scope for me of not just "gaming the benchmarks", as this is actually something I'd now consider using at work.

It's not quite as high as I was seeing with `jiffy` (3,800 req/sec here vs 4,000+ with jiffy), but I'm not confident that was a totally fair comparison. `jiffy` doesn't integrate as nicely with Phoenix, so I was just calling `:jiffy.encode(...)` in the controller and then doing a `text(...)` response. I need to double-check if `json(...)` is doing more work here.

[0] https://github.com/losvedir/transit-lang-cmp/commit/140d693b...

Nowadays, I reached out for some benchmark results. Scala is slower than Java and Kotlin. Can you explain it? https://github.com/losvedir/transit-lang-cmp https://github.com/kostya/benchmarks

I had a chance to update the Go code (commit) to pre-allocate the arrays based on the known length before all the appends, and saw ~30% increase in performance, with top requests per second going from about 8,600 to 11,000.

I recently did a little project to compare several languages (https://github.com/losvedir/transit-lang-cmp) so I contributed to a bunch of those points!

For reference (for the issues you mentioned): 1. This issue was opened almost immediately to solve the weird .only function not working https://github.com/denoland/deno_std/issues/2979 2. That looks weird to me, will get back to you on this one since it should work I think 3. Generally polluting the global namespace isn't great, but because we're only polluting the namespace of a module (and we choose what parts to import), I personally find it quite freeing. I entirely understand how that might feel awkward. 4. you CAN specifying only writing to certain directories! --allow-write=/path/to/dir would allow that!

At least for the ones related to trees, it's just a renaming. Below is a link to the PR. When I initially implemented these trees, I chose the names BSTree and RBTree to keep the names short. I'm guessing the person that proposed renaming them did so to make it more obvious what they are.

https://github.com/denoland/deno_std/pull/2400

The standard library is separate from the runtime. It wouldn't break backward compatibility if you were to update. For example, if you were importing RBTree and upgraded Deno to the latest release, it would keep working just fine. You would only really need to switch to using RedBlackTree instead if there was a change made to it that you wanted.

I think the only time you would need to update your standard module imports to be able to use newer versions of the Deno runtime if the standard module were depending on runtime APIs that have a breaking change.

It is like Demo deprecating fs.exists().[1]

[1]https://github.com/denoland/deno_std/discussions/2102

This was fun to read through.

I would need to profile the code, but the startup time being bad for Deno seems like maybe a combination of the code in here being unoptimized:

https://github.com/denoland/deno_std/blob/0ce558fec1a1beeda3...

(Ex. Lots of temporaries)

And usage of the readFileSync+TextDecoder API instead of readTextFile (which is also a docs issue since it's suggests the first one). It seems the code loads the 100MB into memory, then converts to another 100MB of utf8, then parses with that inefficient csv decoder. The rust and go versions look to be doing stream/incremental processing instead.

But it there's some talk to reconsider it

Sorry to hear that. I want to provide expect API in deno_std in the future: https://github.com/denoland/deno_std/issues/1779

I just migrated the module to Deno and rewrote the test cases using the Deno test runner. Also contributed a bug fix to the test runner that I encountered during the migration. An npm version is still available and automatically generated from the Deno code via a small bash script (rewriting imports, adding an index.ts, etc.).

Much of Node.js is written in C, yet it's still called Node.js.

Deno has some JavaScript/TypeScript in it. On GitHub https://github.com/denoland/deno is 22.8% JavaScript and 13.2% TypeScript, and https://github.com/denoland/deno_std is 68.2% JavaScript and 31.6% TypeScript.

So to me it's misleading about the name, but not about what Deno is written in.