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# valueTransformerName

The name of the transformer to use for the attribute value.

```
var valueTransformerName: String? { get set }
```

## Discussion

The attribute must be of type `NSTransformedAttributeType`.

The transformer must output an `NSData` object from <doc://com.apple.documentation/documentation/Foundation/ValueTransformer/transformedValue(_:)> and must allow reverse transformations.

If this value is `nil`, Core Data uses a default a transformer that uses <doc://com.apple.documentation/documentation/Foundation/NSCoding> to archive and unarchive the attribute value.

---

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