var str = "This is object for string, globle val...";
var obj = { des: 'this is number variable of obj...' };
var fun = function() {
	console.log('this is function obj, i will be long of caller..' + this);
};

obj.fun = fun;
console.log(this === window);
console.log(window.str === str);
console.log(window.obj === obj);
console.log(window.fun === fun);
fun();  ///caller is window
obj.fun();  // caller is obj
fun.apply(str);  // caller is function

for (let value of [0, 'one', true]) {
  console.log(value);
}