# Sort lines of a text document in alphabetical order

Split into lines and sort them by UTF-16 code units.

Canonical: https://1loc.dev/string/sort-lines-of-a-text-document-in-the-alphabetical-order/
Version: 1.0.0
Runtime: JavaScript · Node.js 22 / modern browsers
Verification: Local fixtures; no external services
Updated: 2026-10-28

## Implementation

```javascript
function sortLines(text) { return text.split(/\r?\n/).sort().join('\n'); }
```

## Input

```json
"delivered\nbounced\naccepted"
```

## Expected output

```json
"accepted\nbounced\ndelivered"
```

## Edge case

Input:
```json
"b\nB\na"
```
Output:
```json
"B\na\nb"
```

## Limits

- Default sort order puts uppercase before lowercase, as the edge case shows. Use localeCompare for human ordering.

The lab validates types and size before calling this function. Add equivalent validation at your own trust boundary.

## Source and license

Original: https://github.com/phuocng/1loc/blob/14b481cf60dff1620ab1bb99a43b1f68068cdd9b/contents/sort-lines-of-a-text-document-in-the-alphabetical-order.mdx
Author: Nguyen Huu Phuoc and original contributors
Contributors: See original repository history
Source commit: 14b481cf60dff1620ab1bb99a43b1f68068cdd9b
Copyright (c) 2020 phuoc-ng
License: MIT — https://1loc.dev/licenses/
Maintainer: Oveyon
Modifications: Curated implementation; explicit input contract, edge case and limits. Original MDX retained as inert source evidence.