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JavaScript Object-Oriented JavaScript (2015) Constructor Functions and Prototypes Adding a Prototype

Aaron HARPT
Aaron HARPT
19,845 Points
Posted by Aaron HARPT
Aaron HARPT
19,845 Points

Code challenge question

I am having trouble with the following code challenge:

We're adding a new method to every instance when a Monster is created. Use a prototype instead for the takeDamage method.

monster.js 
function Monster(name) {
  this.name = name;
  this.health = 100;
  Monster.prototype.takeDamage = function (){
    this.health--;
  }
}

3 Answers

Ryan Broughan
Ryan Broughan
12,742 Points
Ryan Broughan
Ryan Broughan
12,742 Points

Here's the passing code:

function Monster(name) {
  this.name = name;
  this.health = 100;
}

Monster.prototype.takeDamage = function (){
    this.health--;
  }

So, you write the Monster() function so it can create the monster with all it's basic properties.

Then in a separate step, you add method(s) you want your Monster(s) to have, by adding them to the prototype.

The prototype then says "All new Monster(s) get this method".

Darryn Smith
Darryn Smith
32,043 Points
Darryn Smith
Darryn Smith
32,043 Points

You're doing great, the only catch is, you want to take the prototype function you wrote and move it OUTSIDE of the main monster constructor.

Ishan Vyas
Ishan Vyas
30,284 Points
Ishan Vyas
Ishan Vyas
30,284 Points

function Monster(name) { this.name = name; this.health = 100; };

Monster.prototype.takeDamage = function (){ this.health--; }