<h1 align="center">string-collapse-leading-whitespace</h1>

<p align="center">Collapse the leading and trailing whitespace of a string</p>

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## Install

This package is [pure ESM](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c). If you're not ready yet, install an older version of this program, 5.1.0 (`npm i string-collapse-leading-whitespace@5.1.0`).

```bash
npm i string-collapse-leading-whitespace
```

## Quick Take

```js
import { strict as assert } from "assert";

import { collWhitespace } from "string-collapse-leading-whitespace";

// if leading/trailing whitespace doesn't contain \n, collapse to a single space
assert.equal(collWhitespace("  aaa   "), " aaa ");

// otherwise, collapse to a single \n (default setting)
assert.equal(collWhitespace("     \n\n   aaa  \n\n\n    "), "\naaa\n");

// does nothing to trimmed strings:
assert.equal(collWhitespace("aaa"), "aaa");

// if there are multiple lines string is still processed in trim-fashion -
// only beginning and ending whitespace is changed:
assert.equal(
  collWhitespace("  abc  \n  def  \n  ghi  "),
  " abc  \n  def  \n  ghi ",
);
```

## Documentation

Please [visit codsen.com](https://codsen.com/os/string-collapse-leading-whitespace/) for a full description of the API.

## Contributing

To report bugs or request features or assistance, [raise an issue](https://github.com/codsen/codsen/issues/new/choose) on GitHub.

## Licence

MIT License

Copyright © 2010-2025 Roy Revelt and other contributors

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