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  "identifier" : "/documentation/AppKit/NSHorizontalDirection/Set",
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  "title" : "NSHorizontalDirection.Set"
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# NSHorizontalDirection.Set

An efficient set of horizontal directions.

```
@frozen struct Set
```

## Topics

### Initializers

[`init(NSHorizontalDirection)`](/documentation/AppKit/NSHorizontalDirection/Set/init(_:))

Creates a set of horizontal directions containing only the specified direction.

### Instance Methods

[`func contains(NSHorizontalDirection) -> Bool`](/documentation/AppKit/NSHorizontalDirection/Set/contains(_:))

[`func insert(NSHorizontalDirection) -> (inserted: Bool, memberAfterInsert: NSHorizontalDirection)`](/documentation/AppKit/NSHorizontalDirection/Set/insert(_:))

[`func remove(NSHorizontalDirection) -> NSHorizontalDirection?`](/documentation/AppKit/NSHorizontalDirection/Set/remove(_:))

[`func update(with: NSHorizontalDirection) -> NSHorizontalDirection?`](/documentation/AppKit/NSHorizontalDirection/Set/update(with:))

### Type Properties

[`static let all: NSHorizontalDirection.Set`](/documentation/AppKit/NSHorizontalDirection/Set/all)

A set containing the all horizontal directions (left and right).

[`static let left: NSHorizontalDirection.Set`](/documentation/AppKit/NSHorizontalDirection/Set/left)

A set containing only the left direction.

[`static let right: NSHorizontalDirection.Set`](/documentation/AppKit/NSHorizontalDirection/Set/right)

A set containing only the right direction.

## Relationships

### Conforms To

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

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

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

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

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

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

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

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

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

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

---

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