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# regex

Use `regex` for regular expressions, replacements, splitting, validation helpers, and text extraction.

```osl
import "std:regex"
```

## Example

```osl
import "std:regex"

log regex.match("[a-z]+", "hello123")
log regex.findAll("[0-9]+", "abc123def456")
```

## API reference

### `regex`

| Method                                                     | Returns   | Notes                                                         |
| ---------------------------------------------------------- | --------- | ------------------------------------------------------------- |
| `regex.match(pattern: any, text: any)`                     | `boolean` |                                                               |
| `regex.find(pattern: any, text: any)`                      | `string`  |                                                               |
| `regex.findAll(pattern: any, text: any)`                   | `array`   | Returns every non-overlapping match.                          |
| `regex.findSubmatch(pattern: any, text: any)`              | `array`   | Returns the full match and capture groups, or an empty array. |
| `regex.replace(pattern: any, text: any, replacement: any)` | `string`  |                                                               |
| `regex.replaceFunc(pattern: any, text: any, fn: any)`      | `string`  |                                                               |
| `regex.split(pattern: any, text: any)`                     | `array`   |                                                               |
| `regex.count(pattern: any, text: any)`                     | `number`  |                                                               |
| `regex.test(pattern: any)`                                 | `boolean` |                                                               |
| `regex.escape(text: any)`                                  | `string`  |                                                               |
| `regex.isValidEmail(email: any)`                           | `boolean` |                                                               |
| `regex.isValidURL(url: any)`                               | `boolean` |                                                               |
| `regex.isValidIPv4(ip: any)`                               | `boolean` |                                                               |
| `regex.isValidIPv6(ip: any)`                               | `boolean` |                                                               |
| `regex.isValidPhone(phone: any)`                           | `boolean` |                                                               |
| `regex.extractEmail(text: any)`                            | `string`  |                                                               |
| `regex.extractEmails(text: any)`                           | `array`   |                                                               |
| `regex.extractURLs(text: any)`                             | `array`   |                                                               |
| `regex.extractHashtags(text: any)`                         | `array`   |                                                               |
| `regex.extractMentions(text: any)`                         | `array`   |                                                               |
| `regex.extractNumbers(text: any)`                          | `array`   |                                                               |
| `regex.extractWords(text: any)`                            | `array`   |                                                               |
| `regex.isAlpha(text: any)`                                 | `boolean` |                                                               |
| `regex.isAlphanumeric(text: any)`                          | `boolean` |                                                               |
| `regex.isNumeric(text: any)`                               | `boolean` |                                                               |
| `regex.isHexadecimal(text: any)`                           | `boolean` |                                                               |
| `regex.isBase64(text: any)`                                | `boolean` |                                                               |
| `regex.isUUID(text: any)`                                  | `boolean` |                                                               |
| `regex.stripTags(text: any)`                               | `string`  |                                                               |
| `regex.stripWhitespace(text: any)`                         | `string`  |                                                               |
| `regex.truncate(text: any, length: any, suffix: any)`      | `string`  |                                                               |
| `regex.slugify(text: any)`                                 | `string`  |                                                               |
| `regex.camelize(text: any)`                                | `string`  |                                                               |
| `regex.snakeCase(text: any)`                               | `string`  |                                                               |
| `regex.kebabCase(text: any)`                               | `string`  |                                                               |
| `regex.maskEmail(email: any)`                              | `string`  |                                                               |
| `regex.maskPhoneNumber(phone: any)`                        | `string`  |                                                               |
| `regex.highlight(text: any, pattern: any, color: any)`     | `string`  |                                                               |
| `regex.wordCount(text: any)`                               | `number`  |                                                               |
| `regex.charCount(text: any, includeSpaces: any)`           | `number`  |                                                               |
| `regex.sentenceCount(text: any)`                           | `number`  |                                                               |

## Notes

* Prefer `import "std:regex"`; the older `import "osl/regex"` spelling remains supported.

## Behavior and limits

Invalid patterns and replacement callback failures return errors. Matching code makes bounded progress after an empty match. Truncation counts Unicode code points and treats a negative limit as zero, while `charCount` reports UTF-8 bytes. IP and Base64 validators use Go's parsers.