vscode-decl

The VS Code extension for Decl: the language (syntax from the site's TextMate grammar, comments, brackets, snippets), a client for decl-lsp — the reference server is bundled, any implementation's decl-lsp runs by decl.server.path — and the editor-side features: the live output preview (decl-evaluate: documents beside the editor), input bindings (decl.inputs), validation and tracing into the output channel, the REPL terminal, decl tasks with the $decl problem matcher, and the fixture runner. The design is docs/tooling/04_extension.md §2–§13.

Build and try

npm run build -w decl-lang        # the reference server the extension bundles
cd extension/vscode && npm run build   # dist/extension.js, syntaxes/, server/

Then Run → Start Debugging with this directory open, or npm run package for a .vsix to install anywhere (Extensions → Install from VSIX…).

Status

Scaffolded, not yet published: the client and every command above are written against the server's decl.* commands; the Test Explorer view, the trace tree view, the syntax-tree document, and the web extension (src/web.ts) follow, and the Marketplace / Open VSX release goes with the language's next version.