# @lezer/javascript

> lezer-based JavaScript grammar

Latest version **1.5.6** (published 2026-10-01) · MIT license · 0 weekly downloads

## Install

```sh
npm install @lezer/javascript
pnpm add @lezer/javascript
yarn add @lezer/javascript
bun add @lezer/javascript
```

## Health

**Score 70/100 (B)** — status: active.

Positive: has types; esm support; no vulnerabilities; recently updated; high maintenance score; high quality score.

Warnings: low downloads.

## Facts

| | |
|---|---|
| Version | 1.5.6 |
| Published | 2026-10-01 |
| First published | 2021-08-11 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Dependencies | 3 |
| Unpacked size | 319.2 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Author | Marijn Haverbeke |
| Maintainers | marijn |

## Links

- npm: https://www.npmjs.com/package/@lezer/javascript
- Repository: https://code.haverbeke.berlin/lezer/javascript
- npm.io page: https://npm.io/package/@lezer/javascript

## Dependencies (3)

- [@lezer/lr](https://npm.io/package/@lezer/lr.md) ^1.3.0
- [@lezer/common](https://npm.io/package/@lezer/common.md) ^1.2.0
- [@lezer/highlight](https://npm.io/package/@lezer/highlight.md) ^1.1.3

## Recent versions

- 1.5.6 (latest) — 2026-10-01
- 1.5.5 — 2026-09-20
- 1.5.4 — 2025-09-18
- 1.5.3 — 2025-09-09
- 1.5.2 — 2025-09-04
- 1.5.1 — 2025-04-18
- 1.5.0 — 2025-04-17
- 1.4.21 — 2024-12-03
- 1.4.20 — 2024-12-02
- 1.4.19 — 2024-10-08
- 1.4.18 — 2024-09-17
- 1.4.17 — 2024-06-11
- 1.4.16 — 2024-05-04
- 1.4.15 — 2024-04-23
- 1.4.14 — 2024-03-30
- … 28 more at https://npm.io/package/@lezer/javascript/versions

## README

# @lezer/javascript

This is a JavaScript grammar for the
[lezer](https://lezer.codemirror.net/) parser system.

It parses modern JavaScript, and supports a `"ts"`
[dialect](https://lezer.codemirror.net/docs/guide/#dialects) to parse
TypeScript, and a `"jsx"` dialect to parse JSX.

The `top` option can be set to `"SingleExpression"` or
`"SingleClassItem"` to parse an expression or class item instead of a
full program.

The code is licensed under an MIT license.

---
_Source: https://npm.io/package/@lezer/javascript · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._