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new F().

F.prototype new [[Prototype]] .

. .

. "prototype" . .

F.prototype "prototype" F . 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 [[Prototype]] .

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

F.prototype

"prototype" .

"prototype" constructor .

          function Rabbit() {}

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

[]

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

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

constructor [[Prototype]] :

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

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

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

[]

constructor .

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

let rabbit = new Rabbit(" ");

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

( ) .

"constructor"

*** "constructor" .**

"prototype" . .

"constructor" .

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

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

"constructor" "prototype" :

          function Rabbit() {}

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

constructor :

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

//            
        

[[Prototype]] . .

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

prototype :

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

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

"prototype"

new Rabbit .

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

let rabbit = new Rabbit();

alert( rabbit.eats ); // true

( ). alert

          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 ); // ?
        

( )

          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 [[Prototype]] rabbit .

.
true.

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

eats .

obj .

let obj2 = new obj.constructor();

obj . .

"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 constructor User .

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') :

constructor user . .
. user User.prototype constructor ( !).
User.prototype Object.prototype .
Object.prototype Object.prototype.constructor == Object . .

let user2 = new Object('Pete') .

. new User new Object. constructor .

( new Object(...) . new Object new Object ).