Answers for "javascript destructuring"

javascript object destructuring

//simple example with object------------------------------
let obj = {name: 'Max', age: 22, address: 'Delhi'};
const {name, age} = obj;

console.log(name);
//expected output: "Max"

console.log(age);
//expected output: 22

console.log(address);
//expected output: Uncaught ReferenceError: address is not defined

// simple example with array-------------------------------
let a, b, rest;
[a, b] = [10, 20];

console.log(a);
// expected output: 10

console.log(b);
// expected output: 20

[a, b, ...rest] = [10, 20, 30, 40, 50];

console.log(rest);
// expected output: Array [30,40,50]

js object destructuring

const hero = {  
  name: 'Batman',  
  realName: 'Bruce Wayne'
};

const { name, realName } = hero;

name;     // => 'Batman',
realName; // => 'Bruce Wayne'

object destructuring javascript

// destructuring object & nested object & combine object into single object
let user = {
  name: 'Mike',
  friend: ["John", "Paul", "Jimmy"],
  location: {
    region:"England",
    country:"United Kingdom"
  },
  aboutMe: {
    status: "Single",
    pet: "Dog",
  }
}

const { name, friend, location, aboutMe: {status , pet} } = user;

console.log(name); // output: "Mike"
console.log(friend);  // output: [ 'John', 'Paul', 'Jimmy' ]
console.log(location); // output: { region: 'England', country: 'United Kingdom' }
console.log(status); // output: "Single"
console.log(pet); // output: "Dog"

//Combining Obj
const newUser = {
  ...user,
  car: {
    make: "Buick",
    year: 2012,
  }
}

console.log(newUser)
// output user obj + car object into one
// {
//   name: 'Mike',
//   friend: [ 'John', 'Paul', 'Jimmy' ],
//   location: { region: 'England', country: 'United Kingdom' },
//   aboutMe: { status: 'Single', pet: 'Dog' },
//   car: { make: 'Buick', year: 2012 }
// }

//Bonus destructuring from object of array
const {friend: [a, ...b]} = user
console.log(a) // output: "John"
console.log(b) // output: ["Paul", "Jimmy"]

object destructuring

const book = {
    title: 'Ego is the Enemy',
    author: 'Ryan Holiday',
    publisher: {
        name: 'Penguin',
        type: 'private'
    }
};

const {title: bookName =  'Ego', author, name: {publisher: { name }} = book, type: {publisher: { type }} = book } = book;

Destructuring Assignment

const HIGH_TEMPERATURES = {
  yesterday: 75,
  today: 77,
  tomorrow: 80
};

//ES6 assignment syntax
const {today, tomorrow} = HIGH_TEMPERATURES;

//ES5 assignment syntax
const today = HIGH_TEMPERATURES.today;
const tomorrow = HIGH_TEMPERATURES.tomorrow;

console.log(today); // 77
console.log(tomorrow); // 80
console.log(yesterday); // "ReferenceError: yesterday is not defined" as it should be.

javascript destructuring

const classDetails = {
  strength: 78,
  benches: 39,
  blackBoard:1
}

const {strength:classStrength, benches:classBenches,blackBoard:classBlackBoard} = classDetails;

console.log(classStrength); // Outputs 78
console.log(classBenches); // Outputs 39
console.log(classBlackBoard); // Outputs 1

javascript object destructuring

//simple example with object------------------------------
let obj = {name: 'Max', age: 22, address: 'Delhi'};
const {name, age} = obj;

console.log(name);
//expected output: "Max"

console.log(age);
//expected output: 22

console.log(address);
//expected output: Uncaught ReferenceError: address is not defined

// simple example with array-------------------------------
let a, b, rest;
[a, b] = [10, 20];

console.log(a);
// expected output: 10

console.log(b);
// expected output: 20

[a, b, ...rest] = [10, 20, 30, 40, 50];

console.log(rest);
// expected output: Array [30,40,50]

js object destructuring

const hero = {  
  name: 'Batman',  
  realName: 'Bruce Wayne'
};

const { name, realName } = hero;

name;     // => 'Batman',
realName; // => 'Bruce Wayne'

object destructuring javascript

// destructuring object & nested object & combine object into single object
let user = {
  name: 'Mike',
  friend: ["John", "Paul", "Jimmy"],
  location: {
    region:"England",
    country:"United Kingdom"
  },
  aboutMe: {
    status: "Single",
    pet: "Dog",
  }
}

const { name, friend, location, aboutMe: {status , pet} } = user;

console.log(name); // output: "Mike"
console.log(friend);  // output: [ 'John', 'Paul', 'Jimmy' ]
console.log(location); // output: { region: 'England', country: 'United Kingdom' }
console.log(status); // output: "Single"
console.log(pet); // output: "Dog"

//Combining Obj
const newUser = {
  ...user,
  car: {
    make: "Buick",
    year: 2012,
  }
}

console.log(newUser)
// output user obj + car object into one
// {
//   name: 'Mike',
//   friend: [ 'John', 'Paul', 'Jimmy' ],
//   location: { region: 'England', country: 'United Kingdom' },
//   aboutMe: { status: 'Single', pet: 'Dog' },
//   car: { make: 'Buick', year: 2012 }
// }

//Bonus destructuring from object of array
const {friend: [a, ...b]} = user
console.log(a) // output: "John"
console.log(b) // output: ["Paul", "Jimmy"]

object destructuring

const book = {
    title: 'Ego is the Enemy',
    author: 'Ryan Holiday',
    publisher: {
        name: 'Penguin',
        type: 'private'
    }
};

const {title: bookName =  'Ego', author, name: {publisher: { name }} = book, type: {publisher: { type }} = book } = book;

Destructuring Assignment

const HIGH_TEMPERATURES = {
  yesterday: 75,
  today: 77,
  tomorrow: 80
};

//ES6 assignment syntax
const {today, tomorrow} = HIGH_TEMPERATURES;

//ES5 assignment syntax
const today = HIGH_TEMPERATURES.today;
const tomorrow = HIGH_TEMPERATURES.tomorrow;

console.log(today); // 77
console.log(tomorrow); // 80
console.log(yesterday); // "ReferenceError: yesterday is not defined" as it should be.

javascript destructuring

const classDetails = {
  strength: 78,
  benches: 39,
  blackBoard:1
}

const {strength:classStrength, benches:classBenches,blackBoard:classBlackBoard} = classDetails;

console.log(classStrength); // Outputs 78
console.log(classBenches); // Outputs 39
console.log(classBlackBoard); // Outputs 1