loading
index.js
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// Object
const obj = {
  name: 'Param',
  city: 'Tallinn',
  age: 20,
  company: 'Learn with Param OU',
};

const { name, age, ...rest } = obj;

console.log(name); // Param
console.log(age); // 20
console.log(rest); // { city: 'Tallinn', company: 'Learn with Param OU', }

// Array example
const personArr = [
  {
    name: 'Param'
  },
  {
    name: 'Ahmed',
  },
  {
    name: 'Jesus',
  }
];

const [first, ...restOfArr] = personArr;

console.log(first);
console.log(restOfArr);

// Destructuring undefined value
const firstObj = {
  name: 'Param',
  city: 'Tallinn',
  age: 20,
  company: 'Learn with Param OU',
};

const { 
  firstName,
  city,
} = firstObj;

console.log(firstName); // undefined
console.log(city); // Tallinn

// Destructuring with default value
const secondObj = {
  firstName: 'Param',
  country: 'Estonia',
};

const { lastName = 'Harrison', country } = secondObj;

console.log(lastName); // Harrison
console.log(country); // Estonia

// false values example
const edgeCase = {
  why: undefined,
  what: null,
  how: 0,
  where: false,
};

const {
  why = 'why',
  what = 'what',
  where = 'where',
  how = 'how',
  notFound = 'Not Found',
} = edgeCase;

console.log(why); // why
console.log(what); // null
console.log(how); // 0
console.log(where); // false
console.log(notFound); // Not Found
node v10.16.0