Improving the development experience with language servers

on YouTube ↗30m

" summary

A new Ruby LSP gem plus a VS Code extension implements the Language Server Protocol over JSON stdio, bringing concrete features not promises: folding ranges computed by parsing to an AST (syntax_tree) and traversing it with a visitor, diagnostics and code actions powered by RuboCop, and formatters that fall back to syntax_tree. The server runs per workspace, merges with other servers (Solargraph), supports format-on-save/type, inlay hints and document highlights, and already works with editors like VSCode and Neovim.

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" chapters (16)

1. 0:00Introduction
2. 1:01Understanding language servers
3. 3:17Problems with language plugins
4. 4:27Language Server Protocol LSP
5. 6:53Requests and Notifications
6. 8:09Interactions between editor and server
7. 10:14The Ruby LSP
8. 10:49Other features
9. 12:16How it works
10. 14:02How to Implement
11. 14:51Analysis
12. 15:53Parsing
13. 23:18Nonpositional requests
14. 23:54Currently supported features
15. 25:17Future features
16. 26:08Questions

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