vldvel

function * generator() {
  yield 1;
  return 2;
  yield 3; // we will never reach this yield
}

const gen = generator();

gen.next(); // {value: 1, done: false}
gen.next(); // {value: 2, done: true}

vldvel

function * generator(arr) {
  for (const el in arr)
    yield el;
}

const gen = generator([0, 1, 2]);

for (const g of gen) {
  console.log(g); // 0 -> 1 -> 2
}

vldvel

function * generator() {
  yield 1;
}

generator.prototype.__proto__; // Generator {constructor: GeneratorFunction, next: ƒ, return: ƒ, throw: ƒ, Symbol(Symbol.toStringTag): "Generator"}

// as Generator is not global variable we have to write something like this
generator.prototype.__proto__.math = function(e = 0) {
  return e * Math.PI;
}

vldvel

Notification.requestPermission((permission) => {
  switch (permission) {
    case 'granted': {
      console.log('Now we can send notifications!');
      break;
    }
    case 'denied': {
      console.log('User close the request pop-up!')
    }
    case 'default': {

vldvel

if (!('Notification' in window)) {
  // Place notification logic here
}

vldvel

Notification
  .requestPermission()
  .then((permission) => {
    if (permission !== 'granted') throw new Error('No access!');
  })
  .then(() => {
    console.log('We have an access!');
    // Handle granted permission here
  })
  .catch((err) => {

vldvel

const title = 'I\'m notification!';

notification(title); // wrong - notification is not defined

Notification(title); // wrong - Failed to construct Notification

new Notification(title); // OK

const notification = new Notification(title); // OK

vldvel

const notificationTitle = 'I\'m notification'; // string

const notificationOptions = {
  tag: 'notification', // tag for notification
  renotify: true, // defalt false, renotifying after old notification
  body: 'Here is my desription', // description under title
  icon: 'https://avatars1.githubusercontent.com/u/22643415', // image URL
  vibrate: [50, 100, 150] // vibration on notification
}

vldvel

const notificationProps = {
  title: 'I\'m notification',
  body: 'Here is my desription',
  icon: 'https://avatars1.githubusercontent.com/u/22643415',
  vibrate: [50, 100, 150]
}

const myNotification = new Notification(notificationProps.title, notificationProps);

function closeNotification(notifyID, time) {

vldvel

switch (Notification.permission) {
  case 'granted': {
    new Notification('Hello world!');
    break;
  }
  case 'denied': {
    alert('No notification for you!');
    break;
  }
  case 'default': {