How does this library handle transliteration of non-ASCII characters?

Question

RepoPilot · Accepted Answer

The **slugify** library handles transliteration of non-ASCII characters through the `transliterate` option, which is **enabled by default**.

## Default Behavior (transliterate: true)

When transliteration is enabled, the library converts Unicode characters to ASCII equivalents. For example [readme.md:L226-L255]:

```js
slugify('Déjà Vu');
//=> 'deja-vu'
```

This works by leveraging the `@sindresorhus/transliterate` dependency [package.json:L26-L55], which handles language-specific transliteration including German umlauts, Vietnamese, Arabic, Russian, and more.

The library also supports locale-specific transliteration through the `locale` option [index.d.ts:L151-L180]:

```js
slugify('Räksmörgås');
//=> 'raeksmoergas'

slugify('Räksmörgås', {locale: 'sv'});
//=> 'raksmorgas'
```

## Disabling Transliteration (transliterate: false)

When transliteration is disabled, non-ASCII characters are **preserved** instead of converted [readme.md:L226-L255]:

```js
slugify('Déjà Vu', {transliterate: false});
//=> 'déjà-vu'
```

The implementation handles this by adjusting the regex pattern used to process characters. When `transliterate === false`, Unicode letter and number categories are preserved in the pattern [index.js:L26-L55]:

```js
if (options.transliterate === false) {
    negationSetPattern += String.raw`\p{L}\p{N}`;
}
```

FOLLOW_UPS:
- What's the difference between transliterate and lowercase options?
- How do custom replacements interact with transliteration?
- Does locale affect transliteration for all languages supported?