rfcs VS Cargo

Congrats!

> Similarly, uv does not yet generate a platform-agnostic lockfile. This matches pip-tools, but differs from Poetry and PDM, making uv a better fit for projects built around the pip and pip-tools workflows.

Do you expect to make the higher level workflow independent of requirements.txt / support a platform-agnostic lockfile? Being attached to Rye makes me think "no".

Without being platform agnostic, to me this is dead-on-arrival and unable to meet the "Cargo for Python" aim.

> uv supports alternate resolution strategies. By default, uv follows the standard Python dependency resolution strategy of preferring the latest compatible version of each package. But by passing --resolution=lowest, library authors can test their packages against the lowest-compatible version of their dependencies. (This is similar to Go's Minimal version selection.)

> uv allows for resolutions against arbitrary target Python versions. While pip and pip-tools always resolve against the currently-installed Python version (generating, e.g., a Python 3.12-compatible resolution when running under Python 3.12), uv accepts a --python-version parameter, enabling you to generate, e.g., Python 3.7-compatible resolutions even when running under newer versions.

This is great to see though!

I can understand it being a flag on these lower level, directly invoked dependency resolution operations.

While you aren't onto the higher level operations yet, I think it'd be useful to see if there is any cross-ecosystem learning we can do for my MSRV RFC: https://github.com/rust-lang/rfcs/pull/3537

How are you handling pre-releases in you resolution? Unsure how much of that is specified in PEPs. Its something that Cargo is weak in today but we're slowly improving.

In the early days of Rust there was a debate about whether to support "green threads" and in doing that require runtime support. It was actually implemented and included for a time but it creates problems when trying to do library or embedded code. At the time Go for example chose to go that route, and it was both nice (goroutines are nice to write and well supported) and expensive (effectively requires GC etc). I don't remember the details but there is a Rust RFC from when they removed green threads:

https://github.com/rust-lang/rfcs/blob/0806be4f282144cfcd55b...

I did some more digging. By RFC 899, I believe Alex Crichton meant PR 899 in this repo:

https://github.com/rust-lang/rfcs/pull/899

Still, no real discussion of why unbuffered stderr.

Rust shares Go's "errors as values + panics" philosophy. Rust also has a standard library API for catching panics. Its addition was controversial, but there are two major cases that were specifically enumerated as reasons to add this API: https://github.com/rust-lang/rfcs/blob/master/text/1236-stab...

> It is currently defined as undefined behavior to have a Rust program panic across an FFI boundary. For example if C calls into Rust and Rust panics, then this is undefined behavior. Being able to catch a panic will allow writing C APIs in Rust that do not risk aborting the process they are embedded into.

> Abstractions like thread pools want to catch the panics of tasks being run instead of having the thread torn down (and having to spawn a new thread).

The latter has a few other similar examples, like say, a web server that wants to protect against user code bringing the entire system down.

That said, for various reasons, you don't see catch_unwind used in Rust very often. These are very limited cases.

Rust has had a stable SIMD vector API[1] for a long time. But, it's architecture specific. The portable API[2] isn't stable yet, but you probably can't use the portable API for some of the more exotic uses of SIMD anyway. Indeed, that's true in .NET's case too[3].

Rust does all this SIMD too. It just isn't in the standard library. But the regex crate does it. Indeed, this is where .NET got its SIMD approach for multiple substring search from in the first place[4]. ;-)

You're right that Rust's standard library is conservatively vectorized though[5]. The main thing blocking this isn't the lack of SIMD availability. It's more about how the standard library is internally structured, and the fact that things like substring search are not actually defined in `std` directly, but rather, in `core`. There are plans to fix this[6].

[1]: https://doc.rust-lang.org/std/arch/index.html

[2]: https://doc.rust-lang.org/std/simd/index.html

[3]: https://github.com/dotnet/runtime/blob/72fae0073b35a404f03c3...

[4]: https://github.com/dotnet/runtime/pull/88394#issuecomment-16...

[5]: https://github.com/BurntSushi/memchr#why-is-the-standard-lib...

[6]: https://github.com/rust-lang/rfcs/pull/3469

Mara's blog post also describes the benefits of standardizing Rust.

Since she created the RFC for standardizing Rust (https://github.com/rust-lang/rfcs/pull/3355) and is also on the team that is working on Rust standardization (https://blog.rust-lang.org/inside-rust/2023/11/15/spec-visio...), I think she was making the point that Rust has good controls in place for adding features while compatibility, not that "Rust does not need a standard".

If she really believed that Rust does not need a standard, why would she create the RFC and join the team working on the effort?

Rust is a great language. There is no reason why it should not have a standard to better formalize its requirements and behaviors.

Dependency Management in Other Languages: We've discussed Python and Node.js in this article, but dependency management is a universal concept in programming. Exploring how you handle dependencies in other languages like Java, C#, or Rust could be beneficial. (I think Rust's cargo is an excellent example of a package manager.)

Nice hack! Would it have been possible back then to use cargo to pull in some dependencies?

The clean solution of cargo script is here: https://github.com/rust-lang/cargo/issues/12207

https://github.com/rust-lang/cargo/pull/13257/files#r1464506...

Yes, I am sure this is going to be a part of Rust 1.77.0 and it will release on 21st March. I say that because of the tag in the PR (https://github.com/rust-lang/cargo/pull/13257#event-11505613...).

I'm no expert on Rust compiler development, but my understanding is that all code that is merged into master is available on nightly. If they're not behind a feature flag (this one isn't), they'll be available in a full release within 12 weeks of being merged. Larger features that need a lot more testing remain behind feature flags. Once they are merged into master, they remain on nightly until they're sufficiently tested. The multi-threaded frontend (https://blog.rust-lang.org/2023/11/09/parallel-rustc.html) is an example of such a feature. It'll remain nightly only for several months.

Again, I'm not an expert. This is based on what I've observed of Rust development.

"Beg", and "passive aggressive" from TFA, is an unnecessarily emotional interpretation of that sentence. It's perfectly neutral. When they imported `cargo-vendor` into cargo removed a feature that was not trivial to reimplement, so they asked for an issue to be opened so that they can see if people want it and so that someone can decide to implement it.

That message *could* be updated to point to https://github.com/rust-lang/cargo/issues/10310 instead of asking for new issues to be created or suggesting the old `cargo-vendor`. (The author of TFA already knows about that issue, since they commented on it before they published their article.)

(You might say it would've been better to let cargo-vendor remain instead of importing it into cargo, but the reason that was done was to ensure it would continue to work with changes to cargo. Indeed that is why cargo-vendor does *not* work properly any more.)

The author provides very surface-level criticism of two Rust tools, but they don't look into why those choices were made.

With about five minutes of my time, I found out:

wrap_comments was introduced in 2019 [0]. There are bugs in the implementation (it breaks Markdown tables), so the option hasn't been marked as stable. Progress on the issue has been spotty.

--no-merge-sources is not trivial to re-implement [1]. The author has already explained why the flag no longer works -- Cargo integrated the command, but not all of the flags. This commit [2] explains why this functionality was removed in the first place.

Rust is open source, so the author of this blog post could improve the state of the software they care about by championing these issues. The --no-merge-sources error message even encourages you to open an issue, presumably so that the authors of Cargo can gauge the importance of certain flags/features.

You could even do something much simpler, like adding a comment to the related issues mentioning that you ran into these rough edges and that it made your life a little worse, or with a workaround that you found.

Alternatively, you can continue to write about how much free software sucks.

[0]: https://github.com/rust-lang/rustfmt/issues/3347

[1]: https://github.com/rust-lang/cargo/pull/10344

[2]: https://github.com/rust-lang/cargo/commit/3842d8e6f20067f716...

And there are IMHO some rough edges around workspaced crates. E.g. https://github.com/rust-lang/cargo/issues/3946

Be careful about doing this globally on in a way that shares the target dir, you'll end up hitting a cargo bug that causes it to combine unexpected code in some cases, which can cause unsound behavior. https://github.com/rust-lang/cargo/issues/12516

For filesystem caches, see https://github.com/rust-lang/cargo/issues/12633

I wonder, is cargo gc solve the problem https://github.com/rust-lang/cargo/pull/12634 ?