Mastering JavaScript

Object-Oriented JavaScript
To have a side effect-free and accurate inheritance mechanism, we have to make sure
that we perform the following:
• Setting the prototype to an instance of the parent initializes the prototype
chain (inheritance); this is done only once (as the prototype object is shared)
• Calling the parent's constructor initializes the object itself; this is done
with every instantiation (you can pass different parameters each time you
construct it)
With this understanding in place, let's define the rest of the objects:
function IndividualContributor() {
Employee.call(this);
this.active_projects = [];
}
IndividualContributor.prototype = Object.create(Employee.prototype);
function TeamLead() {
Manager.call(this);
this.dept = "Software";
this.salary = 100000;
}
TeamLead.prototype = Object.create(Manager.prototype);
function Engineer() {
TeamLead.call(this);
this.dept = "JavaScript";
this.desktop_id = "8822" ;
this.salary = 80000;
}
Engineer.prototype = Object.create(TeamLead.prototype);
Based on this hierarchy, we can instantiate these objects:
var genericEmployee = new Employee();
console.log(genericEmployee);
You can see the following output for the preceding code snippet:
[object Object] {
dept: "None",
name: "",
salary: 0
}
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