# AsyncFilterSequence An asynchronous sequence that contains, in order, the elements of the base sequence that satisfy a given predicate. ``` struct AsyncFilterSequence where Base : AsyncSequence ``` ## Topics ### Structures [`struct Iterator`](/documentation/Swift/AsyncFilterSequence/Iterator) The iterator that produces elements of the filter sequence. ### Type Aliases [`typealias Failure`](/documentation/Swift/AsyncFilterSequence/Failure) The type of the error that can be produced by the sequence. ### Default Implementations [AsyncSequence Implementations](/documentation/Swift/AsyncFilterSequence/AsyncSequence-Implementations) ## Relationships ### Conforms To [`Sendable`](/documentation/Swift/Sendable) [`SendableMetatype`](/documentation/Swift/SendableMetatype) [`AsyncSequence`](/documentation/Swift/AsyncSequence) [`Copyable`](/documentation/Swift/Copyable) [`Escapable`](/documentation/Swift/Escapable) --- 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)