La3 for VS Code

Editor support for Laila Lang (La3) .la3 files:

• Syntax highlighting from a TextMate grammar derived directly from the interpreter's lexer (src/lexer.rs), so keyword, operator, literal, and comment rules match what La3 actually parses (line // and nested /* */ comments, f"..." interpolation with format specs, 0x/0o/0b literals with numeric suffixes, **, ..=, ?., ??, ->, =>, and friends).
• Live diagnostics by running the real la3 check and underlining its lex/parse/type errors as you type. Using the genuine checker means the editor and the command line never disagree.
• Editing support: comment toggling, bracket matching, auto-closing, indentation.
• Commands: La3: Check current file, La3: Run current file, La3: Build interpreter.

How diagnostics work

The extension shells out to the la3 binary (la3 check <file>) and parses its output into editor squiggles. There is no separate language server process and no runtime dependencies; the extension is TypeScript compiled to a single out/extension.js against the vscode API.

It finds the binary in this order:

1. the la3.path setting, if set;
2. target/release/la3, then target/debug/la3 under the workspace (so contributors test against a fresh build);
3. the binary bundled with the extension for your platform (bin/<platform>-<arch>/la3), which makes a plain install self-contained;
4. la3 on your PATH.

If none is found it offers to build the interpreter for you.

Bundled binary

A release build of the interpreter is packaged inside the extension so it works out of the box without a local toolchain. Because the binary is platform-specific, the bundle is keyed by bin/<platform>-<arch>/. Regenerate it for the current platform with:

bun run bundle:bin

The bundled Linux binary is dynamically linked against glibc; on musl-based distros (e.g. Alpine) build your own and point la3.path at it.

Settings

Try it without packaging

1. Build the interpreter once: cargo build --release (from the repo root).
2. Install the extension's build deps: cd editors/vscode && bun install.
3. Open this folder in VS Code and press F5. The bundled launch config compiles the TypeScript first, then opens an Extension Development Host.
4. Open any file under examples/. Highlighting and diagnostics apply immediately to .la3 files. Introduce a typo to see a squiggle, then save and watch it clear.

Develop

The extension is written in TypeScript. Install the build-time dependencies and compile:

cd editors/vscode
bun install
bun run compile      # or: bun run watch

Then press F5 (see above) to launch it.

Install from source

Packaging runs the compile step automatically (vscode:prepublish):

cd editors/vscode
bun install
bunx @vscode/vsce package
code --install-extension la3-language-*.vsix --force

Files