babel-polyfill will emulate a full ES6 environment. For example, without the polyfill, the following code:

function allAdd() {
    return Array.from(arguments).map((a) => a + 2);
}

will be transpiled to:

function allAdd() {
    return Array.from(argument).map(function (a) {
        return a + 2;
    });
}

This code will not work everywhere, because Array.from in not supported by every browser:

Uncaught TypeError: Array.from is not a function

To solve this problem we need to use a polyfill. A polyfill is a piece of code, that replicate the native API that does not exist in the current runtime.

To include the Babel polyfill, we need to install it:

npm install babel-polyfill --save-dev

method 01

With require

require("babel-polyfill");

method 02

If you are using ES6’s import syntax in your application’s entry point, you should instead import the polyfill at the top of the entry point to ensure the polyfills are loaded first.

With ES6 import.

import "babel-polyfill";

method 03

With webpack.config.js, add babel-polyfill to your entry array:

module.exports = {
  entry: ["babel-polyfill", "./app/js"]
};

• Babel
• JavaScript (ES6+)