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<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JS Bin</title>
</head>
<body>

<script id="jsbin-javascript">
/*prototype introduction:

1: all JS object has a default protptype called:
Object.prototype which is an object has lots of built-in methods: to String:
*/

/*
var person = {}
Object.prototype.name = "david";
console.log(person.name);

var p20obj = {}
console.log(p20obj);
*/

/*prototype chain! :
first starts from object itself, if cant find, go to object's prototype,
if can't find, go to prototype of  ocject's prototype, until goes to the ROOT
Object.prototype, if still can't find, then throw error */
var person ={
  name : "person",
  age :20
}

var davidobj = Object.create(person);
davidobj.name = "david";
Object.prototype.name = "object prototype";

/* console.log(davidobj.name);
 console.log(person.name);
 console.log(Object.prototype.name);
*/

//Object.getPrototypeOf(obj) : get the prototype of obj

/*console.log(Object.getPrototypeOf(davidobj) == person) ; //true
console.log(Object.getPrototypeOf(davidobj) == Object.prototype) ; //false*/

/*constructor
when you call the function, it returns you an object*/
function Person(name, age){
  this.name = name;
  this.age = age;
}

var davidObj = new Person("david", 30);
console.log(davidObj);
</script>


<script id="jsbin-source-javascript" type="text/javascript">/*prototype introduction:

1: all JS object has a default protptype called:
Object.prototype which is an object has lots of built-in methods: to String:
*/

/*
var person = {}
Object.prototype.name = "david";
console.log(person.name);

var p20obj = {}
console.log(p20obj);
*/

/*prototype chain! :
first starts from object itself, if cant find, go to object's prototype,
if can't find, go to prototype of  ocject's prototype, until goes to the ROOT
Object.prototype, if still can't find, then throw error */
var person ={
  name : "person",
  age :20
}

var davidobj = Object.create(person);
davidobj.name = "david";
Object.prototype.name = "object prototype";

/* console.log(davidobj.name);
 console.log(person.name);
 console.log(Object.prototype.name);
*/

//Object.getPrototypeOf(obj) : get the prototype of obj

/*console.log(Object.getPrototypeOf(davidobj) == person) ; //true
console.log(Object.getPrototypeOf(davidobj) == Object.prototype) ; //false*/

/*constructor
when you call the function, it returns you an object*/
function Person(name, age){
  this.name = name;
  this.age = age;
}

var davidObj = new Person("david", 30);
console.log(davidObj);

</script></body>
</html>