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new F() .

' . new [[Prototype]] .

. "prototype" . .

(F) F.prototype "prototype" F . F.prototype "prototype" ' .

let animal = {
  eats: true
};

function Rabbit(name) {
  this.name = name;
}

Rabbit.prototype = animal;

let rabbit = new Rabbit(" "); //  rabbit.__proto__ == animal

alert( rabbit.eats ); // true

Rabbit.prototype = animal "new Rabbit [[Prototype]] animal ." .

[]

"prototype", [[Prototype]] . rabbit animal .

F.prototype new F . new F [[Prototype]] .

F.prototype (F.prototype = <another object>) new F another object [[Prototype]] . , [[Prototype]] .

prototype constructor

"prototype" .

( ) "prototype" constructor , constructor .

          function Rabbit() {}

/*  prototype
Rabbit.prototype = { constructor: Rabbit };
*/
        

[]

function Rabbit() {}
//      prototype .
// Rabbit.prototype = { constructor: Rabbit }

alert( Rabbit.prototype.constructor == Rabbit ); // true

new Rabbit constructor , [[Prototype]] .

function Rabbit() {}
//  prototype:
// Rabbit.prototype = { constructor: Rabbit }

let rabbit = new Rabbit(); // {constructor: Rabbit} 

alert(rabbit.constructor == Rabbit); // true ([[Prototype]]  )

[]

constructor constructor .

function Rabbit(name) {
  this.name = name;
  alert(name);
}

let rabbit = new Rabbit(" ");

let rabbit2 = new rabbit.constructor(" ");

( ) .

"constructor"

"constructor" .

"prototype" . "constructor" .

"prototype" . new "constructor" .

function Rabbit() {}
Rabbit.prototype = {
  jumps: true
};

let rabbit = new Rabbit();
alert(rabbit.constructor === Rabbit); // false

constructor "prototype" "prototype" "prototype" , .

          function Rabbit() {}

// Rabbit.prototype   
//     .
Rabbit.prototype.jumps = true
//     Rabbit.prototype.constructor .
        

"prototype" constructor constructor .

          Rabbit.prototype = {
  jumps: true,
  constructor: Rabbit
};

//  constructor       constructor     .
        

[[Prototype]] . .

(F.prototype) [[Prototype]] . F.prototype new F() [[Prototype]] .
F.prototype null . .
new .

"prototype" .

          let user = {
  name: "John",
  prototype: "Bla-bla" //   .
};
        

F.prototype = { constructor : F } "constructor" .

'prototype'

new Rabbit Rabbit "prototype" .

function Rabbit() {}
Rabbit.prototype = {
  eats: true
};

let rabbit = new Rabbit();

alert( rabbit.eats ); // true

( ) ?

          function Rabbit() {}
Rabbit.prototype = {
  eats: true
};

let rabbit = new Rabbit();

Rabbit.prototype = {};

alert( rabbit.eats ); // ?
        

          function Rabbit() {}
Rabbit.prototype = {
  eats: true
};

let rabbit = new Rabbit();

Rabbit.prototype.eats = false;

alert( rabbit.eats ); // ?
        

delete ?

          function Rabbit() {}
Rabbit.prototype = {
  eats: true
};

let rabbit = new Rabbit();

delete rabbit.eats;

alert( rabbit.eats ); // ?
        

          function Rabbit() {}
Rabbit.prototype = {
  eats: true
};

let rabbit = new Rabbit();

delete Rabbit.prototype.eats;

alert( rabbit.eats ); // ?
        

true

Rabbit.prototype [[Prototype]] . .
false

. Rabbit.prototype , Rabbit.prototype rabbit [[Prototype]] .

.
true

delete . delete rabbit.eats rabbit eats , rabbit eats . delete .
undefined

eats eats .

, obj . .

let obj2 = new obj.constructor();

. .

"constructor" .

"prototype" .

function User(name) {
  this.name = name;
}

let user = new User('John');
let user2 = new user.constructor('Pete');

alert( user2.name ); // Pete ( !)

User.prototype.constructor == User .

User.prototype User constructor .

function User(name) {
  this.name = name;
}
User.prototype = {}; // (*)

let user = new User('John');
let user2 = new user.constructor('Pete');

alert( user2.name ); // undefined

user2.name undefined ?

new user.constructor('Pete') .

new user.constructor('Pete') user constructor .
. user User.prototype, User.prototype .
User.prototype {}, Object.prototype. Object.prototype.constructor == Object Object .

let user2 = new user.constructor('Pete'); let user2 = new Object('Pete') . Object . let user2 = new Object('Pete') let user2 = {} . user2.name undefined .