Tiny Cycle.js 0

first.js

Rx.Observable.timer(0, 1000)
  .map(i => `Seconds elapsed ${i}`)
  .subscribe(text => {
    const container = document.querySelector('#app');
    container.textContent = text;
  });

second.js

function main() {
  return {
    DOM: Rx.Observable.timer(0, 1000)
      .map(i => `Seconds elapsed ${i}`)
  }
}

function DOMSideEffect(text$) {
  text$.subscribe(text => {
    const container = document.querySelector('#app');
    container.textContent = text;
  });
}

DOMSideEffect(main().DOM);