var Foo = function(){}
var foo = new Foo()
foo.a = 1
Foo.prototype.a = 2
console.log(foo)

console.log(foo.prototype === undefined)
console.log(foo.__proto__ === Foo.prototype)
console.log(foo.__proto__.constructor === Foo)
console.log(Foo.prototype.constructor === Foo)

//对象
var obj = {}
console.log(obj)
console.log( obj.__proto__ === Object.prototype)
console.log(Object.prototype.__proto__ === null)

//函数
var fn = function(){}
console.log( fn )
console.log(fn.__proto__ === Function.prototype)
console.log(Function.prototype.__proto__ === Object.prototype)
console.log(Object.prototype.__proto__ === null)

//正则
var regExp = /a/
console.log( regExp )
console.log( regExp.__proto__ === RegExp.prototype)
console.log( RegExp.prototype.__proto__ === Object.prototype)
console.log( Object.prototype.__proto__ === null)

//数组

var array = []
console.log(array)
console.log(array.__proto__ === Array.prototype)
console.log(Array.prototype.__proto__ === Object.prototype)
console.log(Object.prototype.__proto__ === null)