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# fileTypes

An array containing types of the promised files being written to the destination location.

```
var fileTypes: [String] { get }
```

## Discussion

[`NSFilePromiseProvider`](/documentation/AppKit/NSFilePromiseProvider) promises one file type per item. The `count` of `fileTypes` should tell you the number of promised files in this item, but that’s not always guaranteed. Some legacy file promisers  list each unique `fileType` only once.

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