# CaseIterable A type that provides a collection of all of its values. ``` protocol CaseIterable ``` ## Overview Types that conform to the `CaseIterable` protocol are typically enumerations without associated values. When using a `CaseIterable` type, you can access a collection of all of the type’s cases by using the type’s `allCases` property. For example, the `CompassDirection` enumeration declared in this example conforms to `CaseIterable`. You access the number of cases and the cases themselves through `CompassDirection.allCases`. ``` enum CompassDirection: CaseIterable { case north, south, east, west } print("There are \(CompassDirection.allCases.count) directions.") // Prints "There are 4 directions." let caseList = CompassDirection.allCases .map({ "\($0)" }) .joined(separator: ", ") // caseList == "north, south, east, west" ``` # Conforming to the CaseIterable Protocol The compiler can automatically provide an implementation of the `CaseIterable` requirements for any enumeration without associated values or `@available` attributes on its cases. The synthesized `allCases` collection provides the cases in order of their declaration. You can take advantage of this compiler support when defining your own custom enumeration by declaring conformance to `CaseIterable` in the enumeration’s original declaration. The `CompassDirection` example above demonstrates this automatic implementation. ## Topics ### Accessing Cases [`allCases`](/documentation/Swift/CaseIterable/allCases-swift.type.property) A collection of all values of this type. [`AllCases`](/documentation/Swift/CaseIterable/AllCases-swift.associatedtype) A type that can represent a collection of all values of this type. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)