[Observable] #tags:JavaScript,RxJS

rx-observable.js

const obs$ = Rx.Observable.create((observer) => {
  observer.next(1)
  // either:
  observer.error(new Error('404'))
  observer.complete()
})

observable.subscribe(
  value => console.log(value),
  err => console.error(value),
  () => console.log('this is the end')
)