Pelago for VS Code

Syntax highlighting, bracket and comment settings and snippets for Pelago (.pel) files.

Install

From a .vsix (until the extension is on the Marketplace): npm ci then npm run package (Node 22 or later; works the same in PowerShell) writes dist/pelago-<version>.vsix. In VS Code: Extensions view, ... menu, "Install from VSIX...". CI builds the same file on every push (the vsix artifact), and the release workflow attaches it to a GitHub release when a tag v<version> is pushed (or when run by hand from the Actions tab).

Colours

The grammar in syntaxes/ names the kind of each word with scopes that all end in .pelago. The extension ships no colour theme and never touches your theme or workbench colours. To make .pel files look different from Rust or TypeScript under any theme, package.json contributes configurationDefaults for editor.tokenColorCustomizations: every rule is anchored to source.pelago, so it applies to .pel files only. The colours are mid-tones (about 3.5:1 or better on both white and #1e1e1e) so they read on dark and light themes. To change them, copy a rule into your own editor.tokenColorCustomizations in settings; yours win.

npm run check (run by CI) fails if a theme, a non-token setting or an unscoped rule is ever added, and tokenizes sample code with the real grammar engine (vscode-textmate) to catch a rule that no longer matches anything. node scripts/tokenize.js <files or folders> tokenizes your own .pel files.

The grammar is generated

syntaxes/pelago.tmLanguage.json is a copy of editors/textmate/pelago.tmLanguage.json in pelagolang/pelago, which is generated from the compiler's keyword tables. Do not edit it by hand. When that file changes on pelago's main, a workflow there (sync-vscode-grammar) opens a PR here with the new copy and a patch version bump.

Language server (errors as you type)

The extension starts pelago lsp for every .pel file, so syntax and type errors appear as squiggles and in the Problems panel, with hover, go to definition, find references, completion and outline.

1. Install the pelago executable and make sure pelago --help works in a terminal (on Windows, add the folder holding pelago.exe to your PATH, then restart VS Code). Or skip PATH and set Pelago: Server Path (pelago.serverPath) to the full path of pelago.exe.
2. Open a .pel file. If the binary cannot be started you get an error message with an Open Settings button.
3. After changing the setting, run Pelago: Restart Language Server from the Command Palette.

pelago.semanticHighlighting (off by default) lets the server's semantic tokens recolour code; leave it off to keep the TextMate colours.

Licence

MIT OR Apache-2.0, at your option: see LICENSE-MIT and LICENSE-APACHE.