console.clear();

​

const { of, from, timer } = rxjs;

const { scan, concatMap, delay, mapTo } = rxjs.operators;

​

const events = [

  { ts: 100000, value: 'a' },

  { ts: 100100, value: 'b' },

  { ts: 101100, value: 'c' },

  { ts: 101120, value: 'd' },

  { ts: 101150, value: 'e' },

  { ts: 101250, value: 'f' },

  { ts: 101300, value: 'g' },

  { ts: 102000, value: 'h' },

  { ts: 102010, value: 'i' },

  { ts: 103010, value: 'j' }

];

​

const head = (events.length > 0 && events[0]) || 0;

​

from(events)

  .pipe(

    scan((p, event) => ({ ...event, diff: event.ts - p.ts }), head),

    concatMap(event => of(event).pipe(delay(event.diff)))

  )

  .subscribe({

    next: event => console.log(event),

    complete: () => console.log('complete')

  });

​