Nodejs Utililty Methods Array Clean

Array.prototype.clean = function() {
  for(let i = 0; i < this.length; i++) {
    if(this[i] === "") {
      this.splice(i, 1);
  return this;
};

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

Array.prototype.clean = function() {
    var i = this.length;
    var clean = []
    while (i--) {
        this[i] = this[i].trim()
        if (this[i] && this[i].length) {
            clean.push(this[i])
    return clean.reverse();

Array.prototype.clean = function() {
  return this.filter(function(a) { 
    return a;
  });

Array.prototype.clean = function(deleteValue) {
  for (var i = 0; i < this.length; i++) {
    if (this[i] == deleteValue) {
      this.splice(i, 1);
      i--;
  return this;
};
...

Array.prototype.clean = function(deleteValue) {
  for (var i = 0; i < this.length; i++) {
    if (this[i] === deleteValue) {         
      this.splice(i, 1);
      i--;
  return this;
};
...

'use strict';
Array.prototype.clean = Array.prototype.clean || function(deleteValue) {
  for (var i = 0; i < this.length; i++) {
    if (this[i] == deleteValue) {         
      this.splice(i, 1);
      i--;
  return this;
...

Array.prototype.clean = function(deleteValue) {
  for (var i = 0; i < this.length; i++) {
    if (this[i] == deleteValue) {         
      this.splice(i, 1);
      i--;
  return this;
};
...

Array.prototype.clean = function(deleteValue) {
    for (var i = 0; i < this.length; i++) {
        if (this[i] === deleteValue) {
            this.splice(i, 1);
            i--;
    return this;
};
...

function rand(from,to)
    return Math.floor(Math.random()*(to-from+1)+from);
Array.prototype.clean = function(deleteValue) {
  for (var i = 0; i < this.length; i++) {
    if (this[i] == deleteValue) {         
      this.splice(i, 1);
      i--;
...