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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

Compiled patterns are cached, so calling a helper repeatedly with the same pattern compiles it once. The cache keeps up to 1,024 distinct patterns; further patterns still work and are compiled on each call.

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.