The Spread Operator Part 2

Part of the Logic & Flow section of Coddy's JavaScript journey — lesson 19 of 65.

The spread operator can merge objects (JSON):

const personalInfo = {name: "John", age: 30};
const jobInfo = {company: "Tech Corp", position: "Developer"};
const completeProfile = {...personalInfo, ...jobInfo};

Now the completeProfile will have all four keys: name, age, company and position:

console.log(completeProfile);
// Output: {name: "John", age: 30, company: "Tech Corp", position: "Developer"}

It can also add new properties and override existing properties while copying:

const user = {name: "Alice", age: 25, mood: "sad"};
const userWithEmail = {
	...user,
	email: "alice@example.com",
	mood: "happy"
};

Challenge

Easy

Create a function named mergeCars that takes two car objects as parameters. The function should merge the second car's properties into the first car's properties and return a new car object without modifying any of the original objects.

Cheat sheet

The spread operator can merge objects:

const personalInfo = {name: "John", age: 30};
const jobInfo = {company: "Tech Corp", position: "Developer"};
const completeProfile = {...personalInfo, ...jobInfo};

It can also add new properties and override existing properties while copying:

const user = {name: "Alice", age: 25, mood: "sad"};
const userWithEmail = {
	...user,
	email: "alice@example.com",
	mood: "happy"
};

Try it yourself

function mergeCars(car1, car2) {
    // Write code here
}
// Do not write anything outside function

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Logic & Flow

1Strings In Depth

String Fundamentals Iterate Over Strings Template Literals String Methods Recap - String Weaver

4JSON Part 2

Iterate Over JSON Nested JSON JSON Optional Chaining Shallow And Deep Copy Recap - Bicycle Shop Recap - Solar System

7Library Management System

Project Overview Adding Books

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Mark As Read

10Manage Festival System

Project Overview Add Movies & Venues