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

Posted by Lewis Long
Lewis Long
2,823 Points

[SOLVED] Please help, I'm afraid I don't quite understand the prototype method.

So I must just be missing something because of right now I don't understand at all what the prototype method is doing or how to create one. Can someone take a look at my work and see what I am doing wrong?

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

1 Answer

Jennifer Nordell
seal-mask
STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

We want to avoid creating a function every single time Monster is called. So we make the prototype. And we do this like this:

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

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

Now the monster will still take damage, but it doesn't need to create a new function every time it does :) Hope that clears things up!