React Native - Why do I need babel or webpack?

Question

I am new pretty new in Javascript world and I am trying to learn and understand React Native.

Why do I find babel and webpack in so many react-native boilerplates? (https://github.com/jhabdas/react-native-webpack-starter-kit)

If I understand correctly babel is for supporting older browsers but I am not using a browser with react-native. RN doesn't compile all js code to native?

Same thing with webpack - why would I need to bundle my js files if they are getting compiled by RN anyways?

Answer 1

Babel is already included with react-native so you have the option of either writing in ES6+ or the older ES5 style.

To clarify, React-native runs on the javascript core on mobile, this means its not in a browser but still renders the JS code so babel is there, in-between, to allow you to write next gen JS code and use React's JSX code.

Here is a list of supported ES6+ features

Some people want additional features not in Babel that ships with react-native so they end up using webpack and custom Babel configurations. Recently they've added support for things like async functions (ES7) so personally, i don't think you need to go the webpack route unless you have a very specific need.