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, - new F().

F.prototype , new [[Prototype]] .

JavaScript . .

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, F.prototype "prototype" F. , F .

let animal = {
  eats: true
};

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

Rabbit.prototype = animal;

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

alert( rabbit.eats ); // true

Rabbit.prototype = animal : new Rabbit() animal [[Prototype]].

[]

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

F.prototype new F [[Prototype]] .

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F.prototype , constructor

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          function Rabbit() {}

/*   
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("White Rabbit");

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

, , , (, ), .

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JavaScript "constructor".

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, , "constructor" .

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

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

, "constructor", // , :

          function Rabbit() {}

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

constructor:

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

//   constructor  ,     
        

[[Prototype]] , -. , .

. :

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

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true.

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

, obj, - , .

let obj2 = new obj.constructor();

- obj, . -, .

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, "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, .
, User.prototype {}, Object.prototype.
, Object.prototype Object.prototype.constructor == Object. , constructor - .

let user2 = new Object('Pete').

, , . new User, new Object. .

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