# mutableSpan A mutable span over the elements of this array. ``` var mutableSpan: MutableSpan { mutating get } ``` ## Return Value A `MutableSpan` over the elements of this array. ## Discussion> Complexity: O(1) when the array’s storage is uniquely referenced, > O(*n*) otherwise. --- 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)