# init(_:as:) Creates a regular expression with a strongly-typed capture list from the given regular expression. ``` init?(_ regex: Regex, as outputType: Output.Type = Output.self) ``` ## Parameters `regex` A regular expression to convert to use a strongly-typed capture list. `outputType` The capture structure to use. ## Discussion You can use this initializer to convert a regular expression with a dynamic capture list to one with a strongly-typed capture list. If the type you provide as `outputType` doesn’t match the capture structure of `regex`, the initializer returns `nil`. ``` let dynamicRegex = try Regex("(.+?): (.+)") if let stronglyTypedRegex = Regex(dynamicRegex, as: (Substring, Substring, Substring).self) { print("Converted properly") } // Prints "Converted properly" ``` --- 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)