Transforms elements from the upstream publisher by providing the current element to a closure along with the last value returned by the closure.
- iOS 13.0+
- macOS 10.15+
- Mac Catalyst 13.0+
- tvOS 13.0+
- watchOS 6.0+
- Xcode 11.0+
The previous result returned by the
A closure that takes as its arguments the previous value returned by the closure and the next element emitted from the upstream publisher.
A publisher that transforms elements by applying a closure that receives its previous return value and the next element from the upstream publisher.