Sigil Language Support for Visual Studio Code

Syntax highlighting, diagnostics, and editing support for the Sigil programming language (.sl files) in Visual Studio Code.

Features

• Syntax Highlighting for keywords, types, strings, numbers, operators, decorators, and string interpolation.
• Diagnostics via the Sigil compiler (sigil --check --format=json) on save.
• Offside Folding based on the language's indentation-significant syntax.
• Smart Indentation after :-terminated lines and else/elif continuations.
• Bracket Matching for (), [], {}.
• Comment Toggling with # (Ctrl/Cmd + /).
• Auto-Closing Pairs for brackets, quotes, and backticks.
• Snippets for fn, class, if/else, for, loop, lambda, pipe, and more.

Requirements

The diagnostics feature needs the Sigil compiler installed locally. By default the extension invokes:

uv run python -m src.main --check --format=json <file>

from a clone of the compiler repo. Override the command, arguments, and working directory under Settings > Sigil.

Installation

1. Open Visual Studio Code.
2. Launch the Command Palette (Ctrl/Cmd + Shift + P).
3. Run Extensions: Install Extensions.
4. Search for Sigil Language Support and install it.
5. Reload VS Code if prompted.

Usage

The extension activates automatically when a .sl file is opened. Diagnostics refresh on save; you can also run Sigil: Check File from the palette.

Example

# Single-line comment
const PI = 3.14159
let message: string = 'Hello, World!'
let interpolated: string = `Your value is {PI}`

fn greet(name: string) -> string:
    return `Hello, {name}!`

class Calculator:
    pub fn add(a: int32, b: int32) -> int32:
        return a + b

let result = Calculator.add(10, 20)

if result > 25:
    loop:
        print('Result is greater than 25')
        break
else:
    print('Result is not greater than 25')

Settings

Key	Default	Description
sigil.diagnostics.enable	true	Run the compiler on save and surface diagnostics inline.
sigil.compiler.command	uv	Command used to run the Sigil compiler.
sigil.compiler.args	["run", "python", "-m", "src.main"]	Arguments preceding the file path. The extension appends --check --format=json <file>.
sigil.compiler.cwd	""	Working directory of the compiler. Empty triggers auto-discovery.
sigil.compiler.timeoutMs	15000	Cancel a check run that takes longer than this.

Contributing

Issues and pull requests: rdenadai/sigil-vscode-language-support.

License

MIT.