Tutorial by Examples

Start by defining a Foo function that we'll use as a constructor. function Foo (){} By editing Foo.prototype, we can define properties and methods that will be shared by all instances of Foo. Foo.prototype.bar = function() { return 'I am bar'; }; We can then create an instance using the ...

Unlike in languages like Python, static properties of the constructor function are not inherited to instances. Instances only inherit from their prototype, which inherits from the parent type's prototype. Static properties are never inherited. function Foo() {}; Foo.style = 'bold'; var foo = ne...

In JavaScript, any object can be the prototype of another. When an object is created as a prototype of another, it will inherit all of its parent's properties. var proto = { foo: "foo", bar: () => this.foo }; var obj = Object.create(proto); console.log(obj.foo); console.log(obj....

Suppose we have a plain object called prototype: var prototype = { foo: 'foo', bar: function () { return this.foo; } }; Now we want another object called obj that inherits from prototype, which is the same as saying that prototype is the prototype of obj var obj = Object.create(prototype); N...

It's an emulation of classical inheritance using prototypical inheritance which shows how powerful prototypes are. It was made to make the language more attractive to programmers coming from other languages. 6 IMPORTANT NOTE: Since ES6 it doesn't make sense to use pseudo-calssical inheritance sinc...

5 With ES5+, the Object.create function can be used to create an Object with any other Object as it's prototype. const anyObj = { hello() { console.log(`this.foo is ${this.foo}`); }, }; let objWithProto = Object.create(anyObj); objWithProto.foo = 'bar'; objWithProto.hell...