is this redundant? -- import React, { Component } from 'react';

Question

at the top of my Create React App created file App.js is the line import React, { Component } from 'react';

Won't React import everything already... and if yes then why is { Component } needed?

Answer 1

Importing Component separately allows you to use Component rather than React.Component. It's a convenience.

Answer 2

It's just a short cut, so that you can write

class MyClass extends Component

Otherwise you'll have to prefix it.

Answer 3

If you don't use webpack and the Tree Shaking feature then It's just syntax sugar

Many people think this

class MyComponent extends Component

is more beautiul than

class MyComponent extends React.Component

But if you're using webpack with tree shaking then webpack will execute dead code elimination in your code

See more:

https://webpack.js.org/guides/tree-shaking/