practice.js

// Inheritance Example with Getters / Setters & "Lexical This"

class Job {
  #name;
  #age;
  #occupation;

  constructor(setName = '', setAge = 0) {
    this.#name = setName;
    this.#age = setAge;
  }

  outputNameDelay() {
    setTimeout(() => console.log(this.#name), 1000);
  }

  set name(newName) {
    this.#name = newName;
  }

  set age(newAge) {
    this.#age = newAge;
  }

  get name() {
    return this.#name;
  }

  get age() {
    return this.#age;
  }
}

class Architect extends Job {
  #occupation = 'architect';

  constructor(setName = '', setAge = 0) {
    super(setName, setAge); // invoke the "parent" constructor
  }

  #privateMethod() {
    console.log("I'm a private method");
  }
}

let architect1 = new Architect('Joe', 34);

architect1.outputNameDelay();
console.log(architect1.name);

// ////////////////////////////////////////

// Arrow Functions

let adderArrowShort = (num1, num2) => num1 + num2;
console.log(adderArrowShort(1, 3));

let squared = num => num * num;
console.log(squared(3));

let getHello = () => 'Hello World';
console.log(getHello());

// ////////////////////////////////////////

// Destructuring Object Parameters

let product = {
  id: '145be9',
  price: 1.35,
  onSale: false,
};

function outputProduct({ id, price }) {
  console.log('Product', id, price);
}

outputProduct(product);

// ////////////////////////////////////////

// Arrays (Iterating)

let sample = ['A', 'B', 'C'];

for (const element of sample) {
  console.log(element);
}

sample.forEach((element, index) => console.log(element + ' at index: ' + index));

// ////////////////////////////////////////

// Arrays (Destructuring)

let [a, b] = sample;

console.log(a, b);

// ////////////////////////////////////////

// Arrays (Spread Syntax)

let sample1 = ['A', 'B', 'C'];
let sample2 = ['D', 'E', 'F'];

let sample3 = [...sample1, ...sample2];

console.log(sample3);

// ////////////////////////////////////////

// Strings (Template Literals)

let x = 5, y = 6;
console.log(`${x} + ${y} = ${x + y}`); // 5 + 6 = 11

let shapes = ['circle', 'square', 'triangle'];
console.log(`My favourite shapes are:${shapes.map((shape, index) => ` ${index + 1}: ${shape}`)}`);

// ////////////////////////////////////////

// Errors (Try / Catch & Throw

function divide(x, y) {
  if (y == 0) {
    throw new Error('Division by Zero!');
  }
  return x / y;
}

let d = 3, e = 0, f;

try {
  f = divide(d, e);
} catch (ex) {
  console.log(`uh oh, an error occurred: ${ex.message}`);
  f = NaN;
}

console.log(`${d} / ${e} = ${f}`); 

// ////////////////////////////////////////