ES6 composition

es6-composition.js

const greeter = {
  doGreeting(msg) {
    console.log(msg);
  }
};

const newYearGreeter = {
  setYear(year) {
	this.year = year;
  },

  doNewYearGreeting() {
    const newYearMsg = `Happy New ${this.year} Year!`;
    this.doGreeting(newYearMsg);
  }
};

Object.assign(newYearGreeter, greeter);
newYearGreeter.setYear(2017);

newYearGreeter.doNewYearGreeting();