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# composite

An attribute that derives its value by composing other attributes.

```
static let composite: NSAttributeDescription.AttributeType
```

## Discussion

Composite attributes support all attribute types except the following:

- [`undefined`](/documentation/CoreData/NSAttributeDescription/AttributeType-swift.struct/undefined)
- [`objectID`](/documentation/CoreData/NSAttributeDescription/AttributeType-swift.struct/objectID)
- [`binaryData`](/documentation/CoreData/NSAttributeDescription/AttributeType-swift.struct/binaryData) (when [`allowsExternalBinaryDataStorage`](/documentation/CoreData/NSAttributeDescription/allowsExternalBinaryDataStorage) is <doc://com.apple.documentation/documentation/Swift/true>)

For more information, see [`NSCompositeAttributeDescription`](/documentation/CoreData/NSCompositeAttributeDescription).

---

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