// 'use strict';

// my js compiler currently didn't support arrow function;
var fn = x => x * x;
console.log(fn(3));



@@ -11,16 +11,37 @@
 rict';%0A%0A
+// node -v = v5.9.1%0A%0A
 // my js
@@ -134,8 +134,280 @@
 (3));%0A%0A%0A
+var square = (x, y) =%3E x * x + y * y;%0A%0A%0Aconsole.log(square(3, 4));%0A%0A%0Avar obj = %7B%0A    birth: 1990,%0A    getAge: function() %7B%0A        var b = this.birth;%0A        var fn = () =%3E new Date().getFullYear() - this.birth;%0A        return fn();%0A    %7D%0A%7D%0A%0Aconsole.log(obj.getAge());%0A%0A%0A

add 14-arrow.js to learn js arrow function