Rust analyzer configuration

[OlekRia]

I use rustic mode in Doom Emacs.

I try to make come changes to rust analyzer:

(use-package lsp-mod
    :ensure t
    :hook ((rust-mode . lsp-deferred))
    :config
    (setq lsp-rust-analyzer-server-display-inlay-hints t)
    (setq lsp-rust-analyzer-inlay-hints-enable t)
    (setq lsp-rust-analyzer-inlay-hints-prefix-type-hints " => ")
    (setq lsp-rust-analyzer-inlay-hints-prefix-parameter-hints "<- ")
    (setq lsp-rust-analyzer-inlay-hints-separator " "))
  
  
  (after! lsp-mode
    (setq lsp-rust-analyzer-server-display-inlay-hints t
          lsp-rust-analyzer-inlay-hints-enable t
          lsp-rust-analyzer-inlay-hints-prefix-type-hints " => "
          lsp-rust-analyzer-inlay-hints-prefix-parameter-hints "<- "
          lsp-rust-analyzer-inlay-hints-separator " "))
  
  ;; Automatically start LSP when opening a Rust file
  (after! rust-mode
    (add-hook 'rust-mode-hook #'lsp-deferred))
  (after! lsp-mode
    (lsp-register-custom-settings
     '(("rust-analyzer.inlayHints.enable" t t)
       ("rust-analyzer.inlayHints.typeHintsPrefix" " => " t)
       ("rust-analyzer.inlayHints.parameterHintsPrefix" "<- " t)
       ("rust-analyzer.inlayHints.separator" " " t)
       ("rust-analyzer.checkOnSave.command" "clippy"))))
```
`

Please take a not on => and <- !
Whatever I do, it's impossible to change that rust analyzer option in emacs.

Please help!

[CeleritasCelery]

If after doom has started and LSP and rustic and loaded (open a rust file). can you change the settings then? you can restart rust-analyzer with lsp-workspace-restart.

[CeleritasCelery]

When you say “doesn’t help” do you mean that you can set the variables, restart rust analyzer but you still don’t see the behavior change? What behavior in RA are you expecting?

[OlekRia]

Exactly. It means: nothing changed. I see the inlayHints in-between code. Like that:

let a: _i32_ = set_a(_num:_ 125);

But I expect seeing what I write above:

let a = set_a(125); => i32 <-i32``

But as I understand it's impossible in emacs. Only in nvim.

[CeleritasCelery]

It looks like this is due to a limitation of neovim where it can only display virtual text at the end of the line. Emacs and VsCode can display it in the correct location. There is a request to build this into rust analyzer. Another option would be to open an issue on Emacs lsp-mode and make this a feature request.

[OlekRia]

Seeing those thread I found, nobody works on it. Meanwhile in Nvim it works. And yes, this is a Rust Analyzer's feature.

here

[CeleritasCelery]

That link is broken. nvim has a translation layer to move the hints to the end of the line since it can't display them inline. lsp-mode could add a translation layer, but I don't believe it exists today.

[psibi]

(use-package lsp-mod

There is a typo here. It should be lsp-mode.

[OlekRia]

Thanks, I fixed. But it doesn't help.