Very simply said, new X is Object.create(X.prototype) with additionally running the constructor function. (And giving the constructor the chance to return the actual object that should be the result of the expression instead of this.) That’s it. 🙂 The rest of the answers are just confusing, because apparently nobody else reads the definition of new … Read more
__proto__ VS. prototype in JavaScript
WeatherWidget.prototype = new Widget; The new keyword calls Widget as a constructor and the return value is assigned to the prototype property. (If you would omit new, you would not call Widget unless you added an argument list, (). However, calling Widget that way might not be possible. It would certainly have the potential to … Read more
When you extend an object, you change its behaviour. Changing the behaviour of an object that will only be used by your own code is fine. But when you change the behaviour of something that is also used by other code there is a risk you will break that other code. When it comes adding … Read more
The examples have very different outcomes. Before looking at the differences, the following should be noted: A constructor’s prototype provides a way to share methods and values among instances via the instance’s private [[Prototype]] property. A function’s this is set by how the function is called or by the use of bind (not discussed here). … Read more
Quick answer: A child scope normally prototypically inherits from its parent scope, but not always. One exception to this rule is a directive with scope: { … } — this creates an “isolate” scope that does not prototypically inherit. This construct is often used when creating a “reusable component” directive. As for the nuances, scope … Read more
Constructor function introduction You can use a function as a constructor to create objects, if the constructor function is named Person then the object(s) created with that constructor are instances of Person. var Person = function(name){ this.name = name; }; Person.prototype.walk=function(){ this.step().step().step(); }; var bob = new Person(“Bob”); Person is the constructor function. When you … Read more