Nodejs Utililty Methods Array Distinct

"use strict";
Array.prototype.distinct = function () { 
  return Array.from(new Set(this)); 
};

Array.prototype.distinct = function () {
  var d = {},
    i;
  this.push(d);
  while ((i = this.shift()) != d) {
    if (!d.hasOwnProperty(i)) {
      this.push(i);
      d[i] = 1;
  return this;
};

Array.prototype.distinct = function() {
    var ret = [];
    for (var i = 0; i < this.length; i++) {
        for (var j = i + 1; j < this.length; ) {
            if (this[i] === this[j]) {
                ret.push(this.splice(j, 1)[0]);
            } else {
                j++;
    return ret;
};
console.log([1, 2, 3, 4, 4, "4", 5].distinct());

Array.prototype.distinct = function(){
  for(var i = 0; i< this.length; i++){
    var n = this[i];
    this.splice(i, 1);
    if(this.indexOf(n) < 0){
      this.splice(i,1,n);
  return this;
...

Array.prototype.distinct = function(){
  for(var i = 0;i < this.length;i++){
    for(var j = i+1;j < this.length;){
      if(this[j] === this[i]){
      for(var k = j;k < this.length;k++){
        this[k] = this[k + 1];
         delete this[this.length - 1];
        this.length--;
...

Array.prototype.distinct = function() {
    var hash = {};
    var a = [];
    for(var i = 0; i < this.length; i++) {
        if(hash.hasOwnProperty(this[i])) {
            continue;
        hash[this[i]] = true;
        a.push(this[i]);
...

Array.prototype.distinct = function () {
    var result = new Array();
    this.forEach(x => {
        if (!result.contains(x))
            result.push(x);
    });
    return result;
};

Array.prototype.distinct = function(){
  var self = this
  var _array = []
  self.forEach(function(e){
    if(_array.contains(e)){
      _array.push(e)
  })
  return _array
...

Array.prototype.distinct = function () {
  var result = [];
  var hash = new Dictionary();
  forEach(this, function (element) {
    if (!hash.contains(element)) {
      result.push(element);
      hash.store(element, element);
  });
...

Array.prototype.distinct = function () {
    var sameObj = function (a, b) {
        var tag = true;
        if (!a || !b) return false;
        for (var x in a) {
            if (!b[x])
                return false;
            if (typeof (a[x]) === 'object') {
                tag = sameObj(a[x], b[x]);
...