Nodejs Utililty Methods String Soundex

String.prototype.soundex = function( ){
  var i, j, r;
  var keyLength = 4; 
  var map = { B:1,F:1,P:1,V:1,C:2,G:2,J:2,K:2,Q:2,S:2,X:2,Z:2,D:3,T:3,L:4,M:5,N:5,R:6 };
  var r = (s = this.toUpperCase().replace(/[^A-Z]/g, "").split("")).splice(0, 1);
  var key = {
      items : [],
      _check: function(e) {
      var m = map[e]; 
...

String.prototype.soundex = function()
  return this.charAt(0).toUpperCase() + this.slice(1).toLowerCase()
    .replace(/\w/g, function($0)
      return String.prototype.soundex.table[$0];
    })
    .replace(/(.)\1+/g, '$1')
    .slice(0, 3)
...

String.prototype.soundex = function(p){
  var i, j, l, r, p = isNaN(p) ? 4 : p > 10 ? 10 : p < 4 ? 4 : p,
  m = {BFPV: 1, CGJKQSXZ: 2, DT: 3, L: 4, MN: 5, R: 6},
  r = (s = this.toUpperCase().replace(/[^A-Z]/g, "").split("")).splice(0, 1);
  for(i = -1, l = s.length; ++i < l;)
    for(j in m)
      if(j.indexOf(s[i]) + 1 && r[r.length-1] != m[j] && r.push(m[j]))
        break;
  return r.length > p && (r.length = p), r.join("") + (new Array(p - r.length + 1)).join("0");
...

String.prototype.soundex = function(p){ 
    var i, j, r, p = isNaN(p) ? 4 : p > 10 ? 10 : p < 4 ? 4 : p,
    m = {BFPV: 1, CGJKQSXZ: 2, DT: 3, L: 4, MN: 5, R: 6},
    r = (s = this.toUpperCase().replace(/[^A-Z]/g, "").split("")).splice(0, 1);
    for(i in s)
        for(j in m)
            if(j.indexOf(s[i]) + 1 && r[r.length-1] != m[j] && r.push(m[j]))
                break;
    return r.length > p && (r.length = p), r.join("") + (new Array(p - r.length + 1)).join("0");
...

String.prototype.soundex.init = function(table)
  String.prototype.soundex.table = {};
  table = table || {
    'bfpv': '1', 
    'cgjkqsxz': '2', 
    'dt': '3', 
    'l': '4', 
    'mn': '5', 
...

var US_ENGLISH_MAPPING = "01360240043788015936020505".split("");
var lookup = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".split("");
String.prototype.soundexRefined = function(){
        if (this == null){ 
            return null;
        var str = this.toUpperCase().replace(/[^A-Z]/g, "");
        if (this.length == 0) {
            return str;
...