# preprocessed(from:eventHandler:) Preprocesses a sequence of examples. ``` func preprocessed(from input: S, eventHandler: EventHandler? = nil) async throws -> AnySequence.Annotation>> where S : Sequence, S.Element == AnnotatedFeature ``` ## Parameters `input` A sequence of examples. `eventHandler` An event handler. ## Return Value The preprocessed examples. --- 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)