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Maybe this question is easy,but I can't understand now.
String.prototype.self=function()
{
return this;
}
var s="s";
alert("s".self()=="s".self()) //false;
alert(s.self()==s.self()) //false;
If you know the reason, please tell me why the result is "false".
825
Mainly there are three types of inheritance in JavaScript. They are, prototypal, pseudo classical, and functional.
JavaScript doesn't use classical inheritance. Instead, it uses prototypal inheritance. In prototypal inheritance, an object “inherits” properties from another object via the prototype linkage.
The ES6 JavaScript supports Object-Oriented programming components such as Object, Class and Methods. Further in Classes we can implement inheritance to make child inherits all methods of Parent Class. This can be done using the extends and super keywords. We use the extends keyword to implement the inheritance in ES6.
By calling the super() method in the constructor method, we call the parent's constructor method and gets access to the parent's properties and methods. Inheritance is useful for code reusability: reuse properties and methods of an existing class when you create a new class.
That's because when a property is accessed from a primitive value, such as "s", the property accesors coerce it internally ToObject, and the comparison fails because it checks two different object references.
For example:
String.prototype.test = function() {
return typeof this;
}
"s".test(); // "object"
It's like comparing:
new String("s") == new String("s"); // false
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