OLOO JavaScript

index.js

'use strict';

// Worker as a module, not as an object.
// Encapsulates behavior.
const Worker = require('./worker');

// Factory method instead of constructor
const jd = Worker.create('Jenny Doe', 19, 'CEO');

// Own properties
console.log(jd); // { name: 'Jenny Doe', age: 19, job: 'CEO' }
// Prototypes' chain!
console.log(jd.__proto__); // { job: 'Offinist' }
console.log(jd.__proto__.__proto__); // { name: 'John Doe', age: 20 }

person.js

'use strict';

// Base Object, default values.
const Person = {
  name: 'John Doe',
  age: 20
};

// Factory function
const createPerson = function (name, age) {
  const proto = Object.create(Person);
  const props = { name, age };
  
  return Object.assign(proto, props);
}

// Exposing the module
exports.proto = Person;
exports.create = createPerson;

worker.js

'use strict';

// Person as a module, not as an object.
// Encapsulates behavior.
const Person = require('./person');

// Parent: Person, default values.
const Worker = {
  __proto__: Person.proto,
  job: 'Officinist'
};

// Factory function
const createWorker = function (name, age, job) {
  const parent = Person.create(name, age);
  const proto = Object.create(worker);
  const props = { __proto__: parent, job };
  
  return Object.assign(proto, props);
}

// Exposing the module
exports.proto = Worker;
exports.create = createWorker;