Why you should migrate your codebase to Typescript

What is typescript?

Typescript is a superset language of JavaScript which means typescript compiles into JavaScript and then executed.

What is JavaScript

JavaScript is a programming language that runs in browsers along with html and CSS.

The Difference

The key difference is that typescript has data types which can catch errors before they are run in JavaScript. JavaScript doesn't catch errors until runtime which can break your application or prevent the way it was designed to run. Typescript can catch these errors before they are complied.

How typescript catches bugs JavaScript doesn't

This is JavaScript code that has an error that is not caught until runtime.

const data = {
 info: {
 name: '',
 date:''
  }
}

function getDate(response) {
 return response.date
}

const date = getDate(data)

Catch the Error? The date property is inside the info object not directly in data.

JavaScript does not count this as an error because in JavaScript you can reference a property that does not exist. This error could crash you site.

How Typescript catches the error

interface data {
  info: {
    name: string,
    date:string,
  }
}

const data:data = {
  info: {
    name: '',
    date: ''
  }
}

function getDate(response:data) {
 return response.date
}

const date = getDate(data)

By using typescript it is able to catch the error as the date property does not exist before it is run.

Now that you know the error you can easily change getDate to

function getDate(response:data) {
 return response.info.date
}

Typescript caught the error before it could be run. Typescript prevents errors and then complies into JavaScript to be run.