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# NSEnumerationOptions

Options for block enumeration operations.

```
struct NSEnumerationOptions
```

## Topics

### Constants

[`NSEnumerationConcurrent`](/documentation/Foundation/NSEnumerationOptions/concurrent)

Specifies that the Block enumeration should be concurrent.

[`NSEnumerationReverse`](/documentation/Foundation/NSEnumerationOptions/reverse)

Specifies that the enumeration should be performed in reverse.

## Relationships

### Conforms To

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

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

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

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

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

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

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

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

---

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