# init(as:_:transform:) Creates a capture for the given component using the specified reference, transforming with the given closure. ``` init(as reference: Reference, @RegexComponentBuilder _ componentBuilder: () -> some RegexComponent, transform: @escaping (W) throws -> NewCapture) where Output == (Substring, NewCapture, C1, C2, C3, C4, C5, C6, C7, C8, C9) ``` ## Parameters `reference` The reference to use for anything captured by `component`. `componentBuilder` A builder closure that generates a regex component to capture. `transform` A closure that takes the substring matched by `component` and returns a new value to capture. If `transform` throws an error, matching is abandoned and the error is returned to the caller. --- 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)