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# pathExtension

The path extension. (read-only)

```
var pathExtension: String? { get }
```

## Return Value

The path extension of the receiver, or `nil` if [`path`](/documentation/Foundation/NSURL/path) is `nil`.

## Discussion

This property contains the path extension, unescaped using the [`replacingPercentEscapes(using:)`](/documentation/Foundation/NSString/replacingPercentEscapes(using:)) method. For example, in the URL `file:///path/to/file.txt`, the path extension is `txt`.

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