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# WebUndefined

`WebUndefined` objects are simply used to represent the JavaScript “undefined” value in methods when bridging between JavaScript and Objective-C. For example, if you invoke a JavaScript function that returns the JavaScript “undefined” value, then a `WebUndefined` object is returned to the Objective-C calling context.

```
class WebUndefined
```

## Topics

### Getting the shared instance

[`undefined`](/documentation/WebKit/WebUndefined/undefined)

Returns the shared `WebUndefined` instance.


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