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

Posted by Barry Ort
Barry Ort
12,373 Points

what is missing?

what am i doing wrong?

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

1 Answer

Nejc Vukovic
.a{fill-rule:evenodd;}techdegree seal-36
Nejc Vukovic
Full Stack JavaScript Techdegree Graduate 51,574 Points

Hi.

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

When you are extending a "Prototype Class" you have to give the object name . prototype . extension function.

That should work.

P.S.: some additional reading about Prototypes: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/prototype