some useful piece of js code

functions.js

//All this following function expression will 
//throw the refrence error, which will raise
//when de-referencing an invalid reference
(function foo() {
	console.log('hello world');
})();
//foo();

!function foo() {
	console.log('beep boop');
}
//foo();

var bar = function foo() {
	console.log('beep boop');
}
//foo();


//Constructor & instanceof
function Beep() {
}
var beep = new Beep();

Boop.prototype = new Beep();
function Boop() {
}
var boop = new Boop();

console.log(beep.constructor === Beep);
console.log(beep instanceof Beep);
console.log(boop.constructor === Beep);
console.log(boop.constructor === Boop);
console.log(boop instanceof Beep);
console.log(boop instanceof Boop);


//Objects private and public members
function MyConstructor(pub, priv) {
	var privateVar = priv;
	this.publicVar = pub;

	this.getPrivateVar = function() {
		return privateVar;
	}

	this.setPrivateVar = function(variable) {
		privateVar = variable;
	}

	this.print = function() {
		console.log('public: ' + this.publicVar + ' private: ' + privateVar);
	}
}
var o = new MyConstructor(100, 200);
console.log(o.privateVar);
console.log(o.getPrivateVar());