'use strict';

// Hint: you need Node.js >= v19.0.0

class Timer extends EventTarget {

#counter = 0;

constructor(delay) {

super();

setInterval(() => {

const step = this.#counter++;

const data = { detail: { step } };

const event = new CustomEvent('step', data);

this.dispatchEvent(event);

}, delay);

}

}

// Usage

const timer = new Timer(1000);

timer.addEventListener('step', (event) => {

console.log({ event, detail: event.detail });

});