Nodejs Utililty Methods Array Count

Array.prototype.countCattle = function(kind) {
  var numKind = 0;
  for (var i = 0; i<this.length; i++) {
    if (this.type == kind){
      numKind++;
  return numKind;
};
...

Array.prototype.countCattle = function(kind) {
  var numKind = 0;
  for (var i = 0; i < this.length; i++) {
    if (this[i].type == kind) {
      numKind++;
  return numKind;
};
...

Array.prototype.countCattle = function (kind) {
  var numKind = 0;
  for (var i = 0; i < this.length; i++) {
    if (this[i].type == kind) {
      numKind++
  return numKind
var canyonCows = [
  { name: "Bessie", type: 'cow', hadCalf: 'Burt'},
  { name: "Bessie", type: 'bull', hadCalf: 'Burt'},
  { name: "Bessie", type: 'cow', hadCalf: 'Burt'},
  { name: "Bessie", type: 'cow', hadCalf: 'Burt'},
  { name: "Bessie", type: 'calf', hadCalf: null},
]
console.log(canyonCows.countCattle('cow'))

Array.prototype.countCattle = function(kind) {
  var numKind = 0;
  for (i in this) {
    if (this[i]["type"] == kind) numKind++;
  return numKind;
};

Array.prototype.calculateCount = function() {
    return this.length;
};
var a = ["1", "2"];
var count = a.calculateCount();
console.log(count);

Array.prototype.countForBreeding = function() {
  var numToBreed = 0;
  for (var i = 0; i < this.length; i++) {
    if (this[i].noCalvesYet()) {
      numToBreed++;
  return numToBreed;
};
...

Array.prototype.countItem = function (item) {
        return this.filter(function (i) {
            return i === item
        }).length;
};

Array.prototype.countOf = function (pValue){
    var count   = 0;
    var lArray  = this || [];
    var lLength = lArray.length
    for (var i = 0 ; i < lLength; i++){
        if (lArray[i] == pValue){
            count++;
    return count;

Array.prototype.countType = function (type) {
  var count = 0
  for( var i = 0, x = this.length; i < x; i++) {
    if (this[i] === type) {
      count++
  return count

Array.prototype.element_count = function(){
  var count = 0;
  for(var i=0; i<this.length; i++){
    if(this[i] != undefined){
      count++;
  return count;