index.jsx

import math from './math.jsx';

console.log(`I can add 2 and 3! ${math.add(2, 3)}`);
console.log(`I can multiply 2 and 3! ${math.multiply(2, 3)}`);

math.jsx

const math = {
  add: (x, y) => { return x + y; },
  multiply: (x, y) => { return x * y; },
};

export default math;

WebpackBlogPostCode.js

var files = [fileA, fileB, fileC];

function(files) {
  var cache = {};
  
  function webpackRequire(index) {
    var module = {
      exports: {},
      cached: false,
    };
    
    var file = files[index];
    file(module, webpackRequire);
    
    return module.exports;
  }
  
  var entryFile = files[0];
  return webpackRequire(entryFile);
}(files);