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

Stephen Selvey
Stephen Selvey
366 Points
Posted by Stephen Selvey
Stephen Selvey
366 Points

Don't need to set firstName or lastName? Why does it say to include them in the call method then?

Don't need to set firstName or lastName? Why does it say to include them in the call method then?

I'm missing something or the prompt is misleading.

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;
}

1 Answer

Erik Nuber
Erik Nuber
20,629 Points
Erik Nuber
Erik Nuber
20,629 Points

This should work. It is giving you the error because you no longer need to set this.firstName and this.lastName.

function Teacher(firstName, lastName, roomNumber) {
  Person.call(this, firstName, lastName);
  this.room = roomNumber;
}

Teacher.prototype = Object.create(Person.prototype);