Combining input streams then using scan to track the results is a common scenario when coding with streams. This lesson walks you through setting up two buttons and merging their input events together to build a streaming Counter component.
const CounterStream = componentFromStream( ?props$ => { ???const { stream: onInc$, handler: onInc } = createEventHandler(); ???const { stream: onDec$, handler: onDec } = createEventHandler(); ???return props$ ?????.switchMap( ?????propos => Observable.merge( ???????onInc$.mapTo(1), ???????onDec$.mapTo(-1) ?????) ???????.startWith(propos.value) ???????.scan((acc, curr) => acc + curr) ???????.map((value) => ({ value, onInc, onDec }))) ?????.map( ?????Counter ?????) ?});[Recompose] Merge RxJS Button Event Streams to Build a React Counter Component
原文地址：http://www.cnblogs.com/Answer1215/p/8087375.html