# next() Produces the next element in the filter sequence. ``` mutating func next() async rethrows -> Base.Element? ``` ## Discussion This iterator calls `next()` on its base iterator; if this call returns `nil`, `next()` returns nil. Otherwise, `next()` evaluates the result with the `predicate` closure. If the closure returns `true`, `next()` returns the received element; otherwise it awaits the next element from the base iterator. --- 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)