# @unified-latex/unified-latex-util-pegjs

> PEGjs grammars and tools for constructing unified-latex ASTs

Latest version **1.8.4** (published 2026-04-03) · MIT license · 0 weekly downloads

## Install

```sh
npm install @unified-latex/unified-latex-util-pegjs
pnpm add @unified-latex/unified-latex-util-pegjs
yarn add @unified-latex/unified-latex-util-pegjs
bun add @unified-latex/unified-latex-util-pegjs
```

## Health

**Score 60/100 (C)** — status: active.

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

Warnings: low downloads.

## Facts

| | |
|---|---|
| Version | 1.8.4 |
| Published | 2026-04-03 |
| First published | 2022-05-13 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Dependencies | 2 |
| Unpacked size | 2.3 MB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 127 |
| Author | Jason Siefken |
| Maintainers | siefkenj |
| Keywords | pegjs, latex, parser, prettier, unified-latex, unified |

## Links

- npm: https://www.npmjs.com/package/@unified-latex/unified-latex-util-pegjs
- Repository: https://github.com/siefkenj/unified-latex
- Homepage: https://github.com/siefkenj/unified-latex#readme
- Issues: https://github.com/siefkenj/unified-latex/issues
- npm.io page: https://npm.io/package/@unified-latex/unified-latex-util-pegjs

## Dependencies (2)

- [@unified-latex/unified-latex-types](https://npm.io/package/@unified-latex/unified-latex-types.md) ^1.8.4
- [@unified-latex/unified-latex-util-match](https://npm.io/package/@unified-latex/unified-latex-util-match.md) ^1.8.4

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## Recent versions

- 1.8.4 (latest) — 2026-04-03
- 1.8.1 — 2024-10-21
- 1.8.0 — 2024-08-22
- 1.7.1 — 2024-03-19
- 1.7.0 — 2024-02-25
- 1.6.1 — 2024-02-18
- 1.6.0 — 2024-01-17
- 1.4.2 — 2023-09-30
- 1.4.0 — 2023-06-20
- 1.3.1 — 2023-03-05
- 1.3.0 — 2023-02-06
- 1.2.2 — 2022-12-15
- 1.2.1 — 2022-11-23
- 1.2.0 — 2022-11-13
- 1.1.0 — 2022-11-06
- … 8 more at https://npm.io/package/@unified-latex/unified-latex-util-pegjs/versions

## README

<!-- DO NOT MODIFY -->
<!-- This file was autogenerated by build-docs.ts -->
<!-- Edit the docstring in index.ts and regenerate -->
<!-- rather than editing this file directly. -->
# unified-latex-util-pegjs

## What is this?

Pegjs grammars to help parse strings into a `unified-latex` Abstract Syntax Tree (AST). Note,
because of the dynamic nature of LaTeX, to get a full AST with arguments attached to macros, etc.,
the tree is parsed multiple times.

Also included are functions to decorate a `Ast.Node[]` array so that Pegjs can process it as if it were
a string. This allows for complex second-pass parsing.

## When should I use this?

If you are building libraries to parse specific LaTeX syntax (e.g., to parse `tabular` environments or
`systeme` environments, etc.).

## Install

```bash
npm install @unified-latex/unified-latex-util-pegjs
```

This package contains both esm and commonjs exports. To explicitly access the esm export,
import the `.js` file. To explicitly access the commonjs export, import the `.cjs` file.

# Functions

## `decorateArrayForPegjs(array)`

Pegjs operates on strings. However, strings and arrays are very similar!
This function adds `charAt`, `charCodeAt`, and `substring` methods to
`array` so that `array` can then be fed to a Pegjs generated parser.

```typescript
function decorateArrayForPegjs(array: any[]): StringlikeArray;
```

**Parameters**

| Param | Type    |
| :---- | :------ |
| array | `any[]` |

## `splitStringsIntoSingleChars(nodes)`

Splits all multi-character strings into strings that are all single characters.

```typescript
function splitStringsIntoSingleChars(nodes: Ast.Node[]): Ast.Node[];
```

**Parameters**

| Param | Type         |
| :---- | :----------- |
| nodes | `Ast.Node[]` |

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