Supporting macro expand for rust.

[YHM404]

When I use vscode, I can expand a rust macro like this example.

How can I do the same things in Helix?

[the-mikedavis]

This is implemented in rust-analyzer as an extension to LSP https://github.com/rust-lang/rust-analyzer/blob/a8d3c46082696b5f7dcf4b960200f2cdc2e48bd8/crates/rust-analyzer/src/lsp_ext.rs

LSP extensions aren't supported currently and should most likely wait for a plugin system. So a plugin system exists and someone creates a plugin to implement rust-analyzer's LSP extensions, macro expansion will not be usable with Helix

[pascalkuthe]

I am sort of confused why tough. It should be possible to create this with an LSP command that either:

• writes the result to a temporary file that is opened with window/showDocument
• replaces the macro with its expansion (potentially separate command)

I might look into submitting a PR for that upstream since RA macro expansion is quite useful

[Velnbur]

This feature is one of the parts, that I'm really missing in helix. Is there a workaround for it for now?