Skip to content

How to copy the properties of an inner object to the outer

Problem: I had a tweet object that for some reason related to the architecture of the app contained the actual tweet data into another object assigned to its data property.

Imagine this:

let tweet = {
  data: {
    id: 1,
    content: 'test'
  }
}

I wanted to move those inner properties on the top level object:

let tweet = {
  id: 1,
  content: 'test'
}

without manually copying those properties over, because the minute I add another property, I introduce a bug.

So here’s what I did:

tweet = Object.assign(tweet, tweet.data)

It’s the same technique you can use to copy properties to another object, but applied in a slightly different way.


→ Here's my latest YouTube video

→ Get my JavaScript Beginner's Handbook

→ I wrote 17 books to help you become a better developer, download them all at $0 cost by joining my newsletter

JOIN MY CODING BOOTCAMP, an amazing cohort course that will be a huge step up in your coding career - covering React, Next.js - next edition February 2025

Bootcamp 2025

Join the waiting list