ArchLang — VS Code extension

Published as ChanMeng.archlang. Full IDE support for .arch files: TextMate syntax highlighting (the grammar from ../) plus a proper LSP language server that reuses the core compiler's language services. It provides:

• Live diagnostics — errors and warnings from compile().diagnostics, as squiggles and in the Problems panel.
• Hover — element/keyword docs at the cursor.
• Completion — context-aware suggestions from the core completion() service.
• Go-to-definition — jump to where an id / binding / component is defined.
• Rename — rename an id/binding across the document.
• Signature help — parameter hints for functions and components.

Not part of the published core. All LSP deps live here; the core stays zero-dependency. The extension depends on the core via file:../.. and pulls it in at runtime through a dynamic import (the core is ESM-only). The language-service functions (hover/completion/definition/rename/signatureHelp) all live in the pure core (src/lsp.ts); this server is a thin LSP adapter over them.

Layout

• src/diagnostics.ts — pure mapping of compile().diagnostics → LSP diagnostics (dependency-injected compile, no LSP import). Unit-tested by the core suite: test/lsp-diagnostics.test.ts.
• src/server.ts — the language server: declares the hover/completion/definition/ rename/signature-help capabilities and, on document change, compiles and sendDiagnostics. Each request delegates to the corresponding core function.
• src/extension.ts — the client: launches the server over IPC for language === "arch".

Build & run

npm run build                         # build the core (dist/) first
npm install --prefix editors/vscode   # installs LSP deps + links the core
npm run build --prefix editors/vscode # tsc -> editors/vscode/dist/

Then press F5 in VS Code with editors/vscode open to launch an Extension Development Host, and open any .arch file: keywords highlight and compiler errors/warnings appear inline (squiggles + Problems panel).

Packaging note: contributes.languages/grammars reference the grammar and language-configuration in ../. For vsce package, copy those two files into this folder (or adjust the paths) so they're included in the .vsix.