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

Where does .fullName come from ?

Where does .fullName come from ?

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

Person.prototype.fullName = function() {
 return this.firstName + " " + this.lastName; 
function Teacher(firstName, lastName, roomNumber) {
Person.call(this, firstName, lastName);
 this.room = roomNumber;

What do you mean by where does it come from?

2 Answers

Steven Parker
Steven Parker
227,114 Points

Based on the code shown above, it's a method of the Person object, defined in person.js.

Graham Tonelli
Graham Tonelli
11,968 Points

You are using a constructor function to instantiate the variable fullname which is a property of the Person object. .fullname 'Comes' from the function itself.

Hope this helps, cheers.