Nodejs Utililty Methods Array Value

Array.prototype.aggregate = function (initialValue, aggregateItemCallback) {
  var result = initialValue; 
  this.each(function (item) {
    result = aggregateItemCallback(result, item);
  })
  return result;

Array.prototype.allValuesSame = function() {
    for(var i = 1; i < this.length; i++)
        if(this[i] !== this[0])
            return false;
    return true;

Array.prototype.allValuesSame = function() {
  for(var i = 1; i < this.length; i++)
    if(this[i] !== this[0])
      return false;
  return true;

var canvas = {};
Array.prototype.allValuesSame = function() {
  for(var i = 1; i < this.length; i++) {
      if(this[i] !== this[0])
          return false;
  return true;

Array.prototype.byField = function(field, value) {
  return this.filter(function ( obj ) {
    return obj[field] == value;
  })[0]

Array.prototype.defaultIfEmpty = function (val) {
  return this.length == 0 ? [val == null ? null : val] : this;
};

Array.prototype.elementWithAttr = function (attr, value) {
    for(var i = 0; i < this.length; i += 1) {
        if(this[i][attr] === value) {
            return this[i];
    return null;
};

Array.prototype.first = function (attribut, value) {
    for (var i = 0; i < this.length; i++) {
        if (this[i][attribut] == value)
            return this.slice(i, i + 1)[0];
    return null;
};

Array.prototype.getNextValue = function(index) {
  let nextIndex = index + 1;
  if(nextIndex < this.length) {
    return this[nextIndex];
  return null;

Array.prototype.hasWhere = function (property, value) {
    "use strict";
    for(var i = 0; i < this.length; i++) {
        if(this[i][property] === value) {
            return true;
    return false;
};
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