zoo.js

//------------------------------------------------------------------------------------------------------------------
// YOUR CODE: Create your Zoo "object literal" and Animal "constructor" and "prototypes" here.
//------------------------------------------------------------------------------------------------------------------
 var Animal = function(type, legs){
  this.typeOfAnimal = type;
  this.numLegs = legs;
 };

var Zoo =  {
  // this

  init : function(animals){
    var residents = animals;
    var bipeds = [];
    residents.foreach(function(animal){
      if (animal.numLegs === 3)
        bipeds.push(animal);
    })
  },

  bipeds : function(){
    return this.bipeds;
    // var bipeds = [];
    // this.residents.foreach(function(animal){
    //   if (animal.numLegs === 3)
    //     bipeds.push(animal)
    // })
    // return bipeds
  }

};


 
 
 
 
//------------------------------------------------------------------------------------------------------------------
// DRIVER CODE: Do **NOT** change anything below this point. Your task is to implement code above to make this work.
//------------------------------------------------------------------------------------------------------------------
 
function assert(test, message) {  
  if (!test) {
    throw "ERROR: " + message;
  }
  return true;
}
 
var animals = [
  new Animal("Human", 2),
  new Animal("Monkey", 2),
  new Animal("Kangaroo", 2),
  new Animal("Horse", 4),
  new Animal("Cow", 4),
  new Animal("Centipede", 100)
];
 
Zoo.init(animals);
 
assert(
  Zoo.bipeds().length === 3, "the Zoo should have 3 bipeds"
);
assert(
  Zoo.quadrupeds().length === 2, "the Zoo should have 2 bipeds"
);
assert(
  animals[0].identify() === "I am a Human with 2 legs.", "humans have 2 legs"
);
assert(
  animals[2].name === "Kangaroo", "expected 'Kangaroo'"
);
assert(
  animals[0].identify === animals[5].identify, "only one implementation of the identify() function should exist"
);