CODEWITHSUNDEEP
javascriptobjectinheritanceecmascript-6prototype
user10581168
user10581168

Reputation:

How Object.create() should create obj2.__proto__ from ob1.prototype when ob1.prototype is undefined?

If we assume this sentence is true: "prototype is the object that is used to build __proto__", how Object.create works? If you do:

let obj1 = {
  name: "obj1",
}

const obj2 = Object.create(obj1);

How Object.create() should create obj2.__proto__ from ob1.prototype when ob1.prototype is undefined??

Maybe Object.create() uses another method of creating prototypical inheritance than constructor or factory functions??

Because, in Object.create() example above this is true:

console.log(obj2.__proto__ === obj1);

but if we do the same thing with constructor function, this will be true:

console.log(obj2.__proto__ === obj1.prototype);

Constructing the object with the function:

function obj1(name) {
  this.name = name;
}

const obj2 = new obj1();

Am I missing something?

Upvotes: 0

Views: 86

Answers (1)

Jonas Wilms
Jonas Wilms

Reputation: 138277

Your sentence "prototype is the object that is used to build __proto__" only applies to functions that get called with new. E.g.

  let dog = new Animal();

equals:

 let dog = Object.create(Animal.prototype); // <<<
 Animal.call(dog);

Prototypal inheritance itself just means that objects contain an "internal" (__proto__) reference to it's prototype. With Object.create you create an object whose prototype is set to the object passed. Therefore

  let inherited = Object.create(obj)

is rather equal to

 let inherited = {};
  inherited.__proto__ = obj;

Upvotes: 1

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