# NSAttributedStringCompletionHandler ``` typedef void (^)(NSAttributedString *, NSDictionary *, NSError *) NSAttributedStringCompletionHandler; ``` ## Discussion Document-Level attributes, like NSBackgroundColorDocumentAttribute, or an error. An implementation of this block type must expect to be called asynchronously when passed to HTML loading methods. --- 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)