# +(_:_:) Creates a new collection by concatenating the elements of a sequence and a collection. ``` static func + (lhs: Other, rhs: Self) -> Self where Other : Sequence, Self.Element == Other.Element ``` ## Parameters `lhs` A collection or finite sequence. `rhs` A range-replaceable collection. ## Discussion The two arguments must have the same `Element` type. For example, you can concatenate the elements of a `Range` instance and an integer array. ``` let numbers = [7, 8, 9, 10] let moreNumbers = (1...6) + numbers print(moreNumbers) // Prints "[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]" ``` The resulting collection has the type of argument on the right-hand side. In the example above, `moreNumbers` has the same type as `numbers`, which is `[Int]`. --- 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)