const Rx = await import('https://unpkg.com/rxjs/_esm2015/index.js')

​

function subscribeToObservable(observable) {

  const next = createEvent()

  const error = createEvent()

  const complete = createEvent()

  let subscription = null;

​

  function unsubscribe() {

    subscription?.unsubscribe()

    subscription = null

  }

  function subscribe() {

    unsubscribe()

    subscription = observable.subscribe({

      next,

      error,

      complete

    })

  }

​

  complete.watch(unsubscribe)

  subscribe()

  return {

    next,

    error,

    complete,

    subscribe,

  }

}

​

const sub = subscribeToObservable(Rx.interval(1000))

​

sub.next.watch(x => console.log('x', x))

​