Re:Mastering Emacs: What's new in Emacs 29.1
by nequo on Friday September 08, 2023 @10:43AM
(#37434142)
One benefit is that you don’t have to write a complex tree sitter mode for every editor. You can write an LSP server once and plug it into every editor.
Rust analyzer also provides compilation errors, lints, and code actions. It would be a lot of unnecessary work to implement and maintain these functionalities five times in five different editors.
However, from what I understand it seems to supply just a parser separate from the Rust compiler (https://github.com/rust-lang/rust-analyzer/tree/master/crate...) trying to keep up with Rust‘s development. So, in principle, it could have been just another treesitter parser plugin, too.
So, again, the LSP framework does not directly provide any magical benefit over a static parsing framework. All the semantic analysis capabilities stem from a good parser.