# AnyBidirectionalCollection.Indices A type that represents the indices that are valid for subscripting the collection, in ascending order. ``` typealias Indices = DefaultIndices> ``` --- 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)