mat3e / polyfill

Babel + core-js example

Babel + core-js

1. npm run babel

   • Creates babel/code.js from src/code.js with Babel transformations
   • Uses just @babel/preset-env, with no additional configuration
   • @babel/preset-env uses .browserslistrc to decide what to transform and how

2. npm run babel-core-js

   • Creates babel-core-js/code.js
   • Uses cross-env to change NODE_ENV
   • Then, @babel/preset-env uses core-js (see .babelrc.js)
   • @babel/preset-env uses .browserslistrc to decide what to transform and polyfill and how

3. npm run docs

   • Creates docs folder with
     • polyfill.html
     • babel-core-js.js
     • original.html
     • original.js
   • Executes webpack 2 times - with the original file (default configuration) and with the Babel + core-js version (webpack-babel-core-js.js webpack configuration)

Example in action

• Original script
• Babel + core-js

Why not using Babel inside Webpack?

The idea is to show Babel and core-js. It's simpler with Babel CLI.

Webpack is just for creating the example webpages with the code got from Babel.