kironroy

'use strict;


const lotteryPromise = new Promise(function (resolve, reject) {
  console.log('lottery draw is happening 🔮');
  setTimeout(function () {
    if (Math.random() >= 0.5) {
      resolve('You WIN 💰');
    } else {
      reject(new Error('You lost your money 😔'));

kironroy

Promise: An object that is used as a placeholder for the future result of an asynchronous operation.
⬇️
Promise: A container for asynchrounusly delivered value.
⬇️
Promise: A container for a future value.

👉 no call backs
👉 no unpredicatable results
👉 we can chain promises for a sequence of asynchrounous operations 

kironroy

'use strict';

// Your tasks:
// 1. Use a constructor function to implement a 'Car'. A car has a 'make' and a
// 'speed' property. The 'speed' property is the current speed of the car in
// km/h
// 2. Implement an 'accelerate' method that will increase the car's speed by 10,
// and log the new speed to the console
// 3. Implement a 'brake' method that will decrease the car's speed by 5, and log
// the new speed to the console

kironroy

class PersonCl {
  constructor(fullName, birthYear) {
    this.fullName = fullName;
    this.birthYear = birthYear;
  }

  // all functions outside the constructor()
  // will be on the prototype
  // not on the object itself

kironroy

const Car = function(make, speed) {
    this.make = make;
    this.speed = speed;
}

Car.prototype.accelerate = function () {
  console.log(`${this.make} is accelerating at ${this.speed + 10} m/hr`);
};

kironroy

'use strict';

// constructor functions

// 1. New {} is created
// 2. function is called, this = {}
// 3. {} linked to prototype
// 4. function automatically return {}

const Person = function (firstName, birthYear) {

kironroy

// setTimeout

const ingredients = ['olives', 'anchovies'];

const pizzaTimer = setTimeout(
  (ing1, ing2) => console.log(`Here is your pizza with ${ing1} and ${ing2} 🍕`),
  3000,
  ...ingredients
);
console.log('Waiting...');

kironroy

const formatCur = function (value, locale, currency) {
  return new Intl.NumberFormat(locale, {
    style: 'currency',
    currency: currency,
  }).format(value);
};

kironroy

const options2 = {
  // style: 'unit',
  style: 'currency',
  // unit: 'mile-per-hour',
  unit: 'celsius',
  currency: 'EUR',
  // useGrouping: false,
};

kironroy

const calcdaysPassed = (date1, date2) =>
  Math.abs((date2 - date1) / (1000 * 60 * 60 * 24));

const days1 = calcdaysPassed(new Date(2037, 3, 4), new Date(2037, 3, 14));
console.log(days1);