switchMap

Transforms each input element into a Source of output elements that is then flattened into the output stream until a new input element is received (at which point the current (now previous) substream is cancelled and the new one is flattened into the output stream).

Nesting and flattening operators

Signature¶

Flow.switchMapFlow.switchMap

Description¶

Transforms each input element into a Source of output elements that is then flattened into the output stream until a new input element is received at which point the current (now previous) substream is cancelled while the Source resulting from the input element is subscribed to and flattened into the output stream. So effectively, only the “latest” Source is flattened into the output stream (which is why this operator is sometimes also called “flatMapLatest”).

Reactive Streams semantics¶