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# ArchiveHeader.FieldKeySet

An object that represents a field key set.

```
final class FieldKeySet
```

## Topics

### Creating a Field Key Set

[`init()`](/documentation/AppleArchive/ArchiveHeader/FieldKeySet/init())

Creates a new empty field key set.

[`init?(String)`](/documentation/AppleArchive/ArchiveHeader/FieldKeySet/init(_:))

Creates a new field key set from the specified comma-separated string of three-letter keys.

[`init(copying: ArchiveHeader.FieldKeySet)`](/documentation/AppleArchive/ArchiveHeader/FieldKeySet/init(copying:))

Creates a copy of the specified field key set.

### Specifying Default Field Key Sets

[`static var defaultForArchive: ArchiveHeader.FieldKeySet`](/documentation/AppleArchive/ArchiveHeader/FieldKeySet/defaultForArchive)

A constant that contains the default key set for an archive.

[`static var defaultForManifest: ArchiveHeader.FieldKeySet`](/documentation/AppleArchive/ArchiveHeader/FieldKeySet/defaultForManifest)

A constant that contains the default key set for a manifest.

## Relationships

### Conforms To

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

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

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

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

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

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

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

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

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

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

---

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