How does primitive types in Javascript have methods and Properties?

user_1728869 0
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var num1 = new Number(5);
typeof(num1); //returns "object"
num1.toString(); //returns "5"

I understand that num1 being an object has a property .__proto__ via which it gets access to .toString() by going down the prototype (.__proto__) chain. 

var num = 5;
typeof(num); //returns "number"
num.toString(); //returns "5"

In above case, num is a primitive type number. It means that it won't have any properties and methods. Then how's it able to get access to .toString() method?

javascript
2 Answers

It means that it won't have any properties and methods.

Javascript has a property called coercion when it comes to primitives; it silently converts the primitive to any object and then accesses the prototype method of the newly constructed number object.

user_63953880

Javascript coerces between primitives and objects. In this case number converts to object in order to access to string.

You can get the object using

//tweaking the to string
Number.prototype.toString = function() {
    return typeof this;
}
var num = 5;
typeof(num); 
num.toString(); //returns "object"
user_50121750
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