Hacker News Reader

Comment by nindalf | Hacker News Reader

For those who don't know, rust-analyzer is an implementation of the Language Server Protocol for the Rust programming language, written in Rust. It assists you while you program, for example finding usages of a piece of code or going to the definition of a function. Basically a Rust IDE that you can plug into any text editor (in theory).

View on HN

It is also worth noting that rust-analyzer is the successor to RLS. If anyone is still using the RLS (most editor plugins can be configured to use either), they should switch to rust-analyzer. It is much much better in almost every possible way, and soon to be made the "official" rust LSP [0].

0: https://github.com/rust-analyzer/rust-analyzer/issues/4224

I got convinced to use rust-analyzer instead of RLS by a comment like yours on hacker news ! I can't thank you enough ! It's almost like Rust became a different -much pleasant- language after that !

How is the Emacs support for this LSP implementation? Does it actually work comparably well to VS Code, or is it going to be like trying to use Emacs as a Java IDE back in the day: fighting your tooling constantly and getting little help from it.

The emacs support is great. I use emacs 'racer' and 'lsp' packages full time for development.

There are two popular emacs packages for rust-analyzer: lsp[0] and eglot[1]. lsp (language server protocol) package is the default for racer. Eglot has far more features and is correspondingly resource hungry.

Detailed type information has a super helpful impact on my ability to review Rust code in general. I find reviewing rust code much more productive when I can see what owns a variable, how long it lives, and how it's being used (immutable vs mutable). So yea, lsp or eglot. Super helpful.

[0] https://emacs-lsp.github.io/lsp-mode/ [1] https://github.com/joaotavora/eglot

I use rust-analyzer with Emacs every day for work. There was a small amount of initial setup time (one or two bugs that had to be fixed with line or two in the init file), and since then, I haven't had to do anything; it's just worked fine.

I use it in Emacs every day since a few years. It mainly works, but I still haven't figured out the best way to set the right feature flag combinations if I work in a crate that uses them a lot. In these cases, if some code requires a feature to be enabled, analyzer does nothing because it compiles with the feature disabled.

It's not bothering me that much that I'd find a solution, because I don't need the help of analyzer in crates that I maintain anymore...

Anecdote: it worked fine for me in spacemacs. I switched from spacemacs to VSCode because the latter's vi emulation was better, not because r-a didn't work well.

I use it with Spacemacs for 6+ months now and it's only getting better with time.

It's 99% reliable.

If you want to use the rust-analyzer LSP, you might want to switch to the rust-analyzer VSCode extension instead of the Rust one. There is a reason the "official" one doesn't use it yet and having a flaky autocomplete is the worst.

Reply on news.ycombinator.com