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# NSKeyValueOperator

These constants define the available array operators. See [Using Collection Operators](https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/KeyValueCoding/CollectionOperators.html) for more information.

```
struct NSKeyValueOperator
```

## Topics

### Type Properties

[`NSAverageKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/averageKeyValueOperator)

The @avg array operator.

[`NSCountKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/countKeyValueOperator)

The @count array operator.

[`NSDistinctUnionOfArraysKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/distinctUnionOfArraysKeyValueOperator)

The @distinctUnionOfArrays array operator.

[`NSDistinctUnionOfObjectsKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/distinctUnionOfObjectsKeyValueOperator)

The @distinctUnionOfObjects array operator.

[`NSDistinctUnionOfSetsKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/distinctUnionOfSetsKeyValueOperator)

The @distinctUnionOfSets array operator.

[`NSMaximumKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/maximumKeyValueOperator)

The @max array operator.

[`NSMinimumKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/minimumKeyValueOperator)

The @min array operator.

[`NSSumKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/sumKeyValueOperator)

The @sum array operator.

[`NSUnionOfArraysKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/unionOfArraysKeyValueOperator)

The @unionOfArrays array operator.

[`NSUnionOfObjectsKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/unionOfObjectsKeyValueOperator)

The @unionOfObjects array operator.

[`NSUnionOfSetsKeyValueOperator`](/documentation/Foundation/NSKeyValueOperator/unionOfSetsKeyValueOperator)

The @unionOfSets array operator.

## Relationships

### Conforms To

[`Sendable`](/documentation/Swift/Sendable)

[`Hashable`](/documentation/Swift/Hashable)

[`RawRepresentable`](/documentation/Swift/RawRepresentable)

[`Equatable`](/documentation/Swift/Equatable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

---

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