es.js

/* ES5 */

var standardFunction = function () {
  /* do stuff */
}

function otherStandardFunction () {

}

var objectThing = {
  methodName: function () {}
}

/* access self in a function */

/* self binding stuff */
var objectThing = {
  someProperty: 'stuff',
  methodName: function () {
    var self = this;

    var someStupidFunction = function () {
      return self.someProperty;
    };

    return someStupidFunction();
  }
}

/* ES6+ */

/* all of the above + */

/* ARROW FUNCTIONS */
/* referentially transparent */
let arrowFunction = (argument) => {

}

let arrowFunction = argument => {

}

/* no more self binding stuff */

var objectThing = {
  someProperty: 'stuff',
  methodName: function () {
    var someStupidFunction = () => {
      return this.someProperty;
    };

    return someStupidFunction();
  }
}

/* parenthesis(sp?) notation
/* implicitly returns the return value of someFunction */
/* note: you can't do more than one operation */
let arrowFunction = argument => (
  someFunction()
)
let arrowFunction = argument => someFunction()

/* object literals */

es6ObjectLiteral = {
  es5Function: function () { console.log(es6ObjectLiteral === this) },
  es6Function() { console.log(es6ObjectLiteral === this) }
  arrowFunction: () => { console.log(es6ObjectLiteral === this) }
}

es6ObjectLiteral.es5Function()   // true
es6ObjectLiteral.es6Function()   // true
es6ObjectLiteral.arrowFunction() // false