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JavaScript Object-Oriented JavaScript (2015) Prototypal Inheritance Setting Up the Prototype Chain

Tiffany White
Tiffany White
5,373 Points
Posted by Tiffany White
Tiffany White
5,373 Points

I don't understand what I am doing wrong.

I am doing exactly what MDN said I should do and the example from Treehouse. What I am doing wrong here? It says I don't need the firstName or lastName properties but when I remove them it tells me to add them. I'm lost.

person.js 
function Person(firstName, lastName) {
  this.firstName = firstName;
  this.lastName = lastName;
}

Person.prototype.fullName = function() {
 return this.firstName + " " + this.lastName; 
};
teacher.js 
function Teacher(firstName, lastName, roomNumber) {
  Person.call(this, firstName, lastName);
  this.firstName = firstName;
  this.lastName = lastName;
  this.room = roomNumber;
}
Ryan Zimmerman
Ryan Zimmerman
3,854 Points
Ryan Zimmerman
Ryan Zimmerman
3,854 Points

So are you creating a prototype of Person for which Teacher will be a new Person?

2 Answers

Ryan Zimmerman
Ryan Zimmerman
3,854 Points
Ryan Zimmerman
Ryan Zimmerman
3,854 Points

So I don't know the exact challenge and I don't want to send you in the wrong direction but I would think it is something like this.

function Person (firstName, lastName) { this.firstName: firstName, this.lastName: lastName }

var Teacher = new Person();

Person.prototype.fullName = function () { return this.firstName + ' ' + this.lastName; }

Teacher.prototype.roomNumber = //how ever you want to build it

Tiffany White
Tiffany White
5,373 Points
Tiffany White
Tiffany White
5,373 Points

I need to use the call() method for prototypal inheritance/chaining. Thanks anyway.