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

San Francisco
San Francisco
28,373 Points
Posted by San Francisco
San Francisco
28,373 Points

Halp please

not sure how to fix can anyone please show a working solution

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

2 Answers

Maciej Sitko
Maciej Sitko
16,164 Points
Maciej Sitko
Maciej Sitko
16,164 Points

Is this supposed to add a prototype? If so, try:

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

Monster.prototype.takeDamage = function (){
    this.health--;
  }
John Tasto
John Tasto
21,587 Points
John Tasto
John Tasto
21,587 Points

They want you to take the takeDamage function out of the constructor so it doesn't create a copy of the function every time a Monster object is made. Instead it should go in Monster.prototype, an object shared across all objects created by the Monster constructor:

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

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