Question

So if I was to create an object literal like this..

var person1 = {

  age : 28,
  name : 'Pete'  }

Then I add a function to the object…

  person1.sayHelloName = function(){

     return 'Hello ' + this.name;

  };

  alert(person1.sayHelloName());

Im wondering where the ‘prototype’ keyword comes into all this. I cant add a prototype to an object (only to a function constructor) so would I be able/have to use the prototype in this scenario.

Answer 1

You can’t use the prototype in this way because, like you say, it’s used to add properties to a constructor which must be defined with the function() keyword. What you are doing in your example is extending the person1 object, but that object is just a single variable and not an instantiable class. Meaning you can’t “create” another person1 using the new keyword, whereas you could if it were an instance of a defined class.