GreyCat for Visual Studio Code
Language support for GreyCat (.gcl) — completion, diagnostics, formatting, hover, goto-definition, rename, code actions. Backed by greycat-analyzer, which doubles as a CLI linter and formatter for CI.
Analyzer binary
The extension talks to the greycat-analyzer binary over LSP. On first launch in a .gcl workspace, if the binary isn't already installed, the extension offers to download the latest release from GitHub for your platform. The download is per-user and lives in VS Code's extension storage — no shell PATH shenanigans needed.
You can also use a binary you installed yourself: put it on PATH (greycat-analyzer --version should work) or point greycat.serverPath at an absolute path. Discovery order: greycat.serverPath → PATH → managed download → first-run prompt. First hit wins.
The extension periodically checks GitHub for newer releases (daily by default, configurable). When a newer release is available, it shows a notification; updates are never silent. Use GreyCat: Check for Analyzer Updates to force a check, or GreyCat: Download / Update LSP Server to install the latest right now.
Pre-built binaries exist for Linux x86_64 (glibc / musl), Apple Silicon macOS, and Windows x86_64. Intel Mac (darwin/x64) has no native artifact yet — install manually per the project README.
Activation
Auto-activates when the workspace contains a project.gcl. The entrypoint's @library / @include pragmas define the analyzed module set — there is no flat directory walk, so projects nested in subfolders work as long as each has its own project.gcl.
Settings
| Setting |
Default |
What it does |
greycat.trace.server |
info |
LSP server log verbosity. off / info / debug / trace. Output goes to the GreyCat output channel. |
greycat.lintLibs |
false |
Surface lint warnings for vendored modules under lib/<name>/. Off by default so your own code's signal doesn't drown in stdlib noise. Type-relation diagnostics always surface. |
greycat.diagnosticsDebounceMs |
150 |
Debounce window (ms) between full analyzer publishes while you type. 0 runs the analyzer on every keystroke. |
greycat.serverPath |
"" |
Absolute path to a greycat-analyzer binary. When set, overrides every other discovery step. |
greycat.checkForUpdates |
daily |
How often to probe GitHub for newer releases. off / onStartup / daily / weekly. |
Changes to these settings prompt you to restart the server.
Commands
| Command |
Action |
GreyCat: Restart LSP Server |
Stop and re-spawn the LSP server. |
GreyCat: Download / Update LSP Server |
Download the latest analyzer release into the extension's managed storage and restart. |
GreyCat: Show LSP Server Path |
Log the resolved binary path, its source (settings / PATH / managed), its --version output, and the latest known release tag. |
GreyCat: Check for LSP Server updates |
Force an update probe outside the auto-check cadence. |
Troubleshooting
greycat-analyzer not found and the download prompt didn't appear. Try GreyCat: Download / Update LSP Server from the command palette directly. If that fails, install manually via the project README and either restart VS Code (so it picks up the updated PATH) or set greycat.serverPath to the binary's absolute path.
Suggestions not appearing on macOS. Ctrl+Space may be claimed by the system "Select previous input source" shortcut. Disable it under System Settings → Keyboard → Keyboard Shortcuts → Input Sources, then restart VS Code.
Stale diagnostics or hover. Run GreyCat: Restart LSP Server from the command palette. If the issue reproduces from a clean restart, please file an issue with a minimal repro.
Skipped a version notification and want it back. Re-run GreyCat: Check for LSP Server updates — the manual command bypasses the "skip this version" gate.
Bugs and feedback
Issues for the extension, the analyzer, the formatter, and the LSP server all live in the same place: github.com/maxleiko/greycat-analyzer/issues.
License
MIT.
