javascript - Do I need to import React for stateless functional components?

Question

All around me (e.g. blog posts, code) I see code for React stateless functional components in which React is imported even though it's never used.

import React from 'react';

function MyComponent() {
  return <div>Howdy!</div>;
}

export default MyComponent;

I'm wondering why we need to import React when it's not actually used (in any explicit manner).

I'm also surprised that my linter doesn't complain about the un-used import.

Is there some reason to import React into functional components that I'm not aware of?

Answer 1

Yes, there is. Babel transpiles JSX to use React:

<div></div>

To:

React.createElement("div", null);

So your JSX is internally transpiled to use React.createElement in pure JavaScript, which does use React. Remember that JSX is just syntactic sugar over pure JavaScript. If you don't specifically import it, it will report that React isn't defined.

Update Sep 2021: In React 17, a new JSX transform is introduced which automatically transforms JSX without using React.createElement. This allows us to use JSX without importing React. More on docs