Part 1 - Javascript module types (CJS, AMD, UMD, ESM, WTF?)

AMD.js

// data/names.js

define('names', [], function() {
  return ({
    john: 'John Doe',
    foo: 'Foo Bar',
    test: 'Test User',
    homer: 'Homer Jay Simpson'
  })
});



// lib/greetings.js

define('greetings',['../data/names'], function(names) {
  return ({
    sayHelloTo: function(user) {
      return `Hello ${names[user]} !`;
  },
  sayGoodbyeTo: function(user) {
    return `Goodbye ${names[user]} !`;
  }
  })
});



// index.js

define('index',['./lib/greetings'], function(greetings) {
  console.info(greetings.sayHelloTo('foo'));
  console.info(greetings.sayGoodbyeTo('foo'));
});

CJS.js

// data/names.js

const names = {
  john: 'John Doe',
  foo: 'Foo Bar',
  test: 'Test User',
  homer: 'Homer Jay Simpson'
};

module.exports = names



// lib/greetings.js

const names = require('../data/names');

module.exports.sayHelloTo = function(user) {
  return `Hello ${names[user]} !`;
}

module.exports.sayGoodbyeTo = function(user) {
  return `Goodbye ${names[user]} !`;
}



// index.js

const greetings = require('./lib/greetings')

console.info(greetings.sayHelloTo('john'));
console.info(greetings.sayGoodbyeTo('john'));

ESM.js

// data/names.js

export const names = {
  john: "John Doe",
  foo: "Foo Bar",
  test: "Test User",
  homer: "Homer Jay Simpson"
};



// lib/greetings.js

import { names } from "../data/names";

export const sayHelloTo = function(user) {
  return `Hello ${names[user]} !`;
};

export const sayGoodbyeTo = function(user) {
  return `Goodbye ${names[user]} !`;
};



// index.js

import {sayHelloTo, sayGoodbyeTo} from "./lib/greetings";

console.info(sayHelloTo("homer"));
console.info(sayGoodbyeTo("homer"));

UMD.js

// data/names.js

(function(root, factory) {
  if (typeof define === "function" && define.amd) {
    define([], factory);
  } else if (typeof exports === "object") {
    module.exports = factory();
  } else {
    root.returnExports = factory(root);
  }
})(this, function() {
  return {
    john: "John Doe",
    foo: "Foo Bar",
    test: "Test User",
    homer: "Homer Jay Simpson"
  };
});



// lib/greetings.js

(function(root, factory) {
  if (typeof define === "function" && define.amd) {
    define(["../data/names"], factory);
  } else if (typeof exports === "object") {
    module.exports = factory(require("../data/names"));
  } else {
    root.returnExports = factory(root.names);
  }
})(this, function(names) {
  function sayHelloTo(user) {
    return `Hello ${names[user]} !`;
  }

  function sayGoodbyeTo(user) {
    return `Hello ${names[user]} !`;
  }

  return {
    sayHelloTo,
    sayGoodbyeTo
  };
});



// index.js

(function(root, factory) {
  if (typeof define === "function" && define.amd) {
    define(["./lib/greetings"], factory);
  } else if (typeof exports === "object") {
    module.exports = factory(require("./lib/greetings"));
  } else {
    root.returnExports = factory(root.greetings);
  }
})(this, function(greetings) {
  console.info(greetings.sayHelloTo("test"));
  console.info(greetings.sayGoodbyeTo("test"));

  return null;
});