# enumerateContainerBoundaries(from:reverse:using:) Enumerates all the container boundaries starting from the location you specify. ``` optional func enumerateContainerBoundaries(from location: any NSTextLocation, reverse: Bool, using block: (any NSTextLocation, UnsafeMutablePointer) -> Void) ``` ## Parameters `location` The location where the enumeration starts. `reverse` A Boolean value that indicates the enumeration starts at the end of the container. `block` A closure to invoke to evaluate the container boundaries; end the enumeration early by returning `false`. ## Discussion This is an optional method you implement to enumerate the text up to the container or page boundary when the text selection data provider supports this layout functionality. --- 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)