const set = new Set([1, 1, 2, 3, 4]);

console.log(set);

// counter.js
let counter = 10;
export default counter;

// index.js
import myCounter from './counter';

myCounter += 1;

console.log(myCounter);

const name = 'Lydia';
age = 21;

console.log(delete name);
console.log(delete age);

const numbers = [1, 2, 3, 4, 5];
const [y] = numbers;

console.log(y);

const user = { name: 'Lydia', age: 21 };
const admin = { admin: true, ...user };

console.log(admin);

const person = { name: 'Lydia' };

Object.defineProperty(person, 'age', { value: 21 });

console.log(person);
console.log(Object.keys(person));

const settings = {
  username: 'lydiahallie',
  level: 19,
  health: 90,
};

const data = JSON.stringify(settings, ['level', 'health']);
console.log(data);

let num = 10;

const increaseNumber = () => num++;
const increasePassedNumber = number => number++;

const num1 = increaseNumber();
const num2 = increasePassedNumber(num1);

console.log(num1);
console.log(num2);

const value = { number: 10 };

const multiply = (x = { ...value }) => {
  console.log((x.number *= 2));
};

multiply();
multiply();
multiply(value);
multiply(value);

class Dog {
  constructor(name) {
    this.name = name;
  }
};

class Labrador extends Dog {
  // 1
  constructor(name, size) {
    this.size = size;
  }
  // 2
  constructor(name, size) {
    super(name);
    this.size = size;
  }
  // 3
  constructor(size) {
    super(name);
    this.size = size;
  }
  // 4
  constructor(name, size) {
    this.name = name;
    this.size = size;
  }

};