Nodejs Utililty Methods Number Value Check

Number.prototype.odd = function(){
  return ( ( this % 2 ) == 1 )

Number.prototype.isBetween = function(l,h){
  return (this >= l.val() && this <= h.val());

Number.prototype.isBetween = function (min, max, inclusive) {
  return inclusive
    ? this >= min && this <= max
    : this > min && this < max;
};

Number.prototype.isBetween = function isBetween(a, b) {
  if(a <= this) {
    return this <= b;
  return this >= b;

Number.prototype.even = function(){
    return (this % 2 === 0);
};

var puts = require("sys").puts;
Number.square = function(n) {
  return n * n
Number.even = function(n) {
  return n % 2 == 0
Number.odd = function(n) {
  return !this.even(n)
...

String.prototype.isNumber = function(){
  return !isNaN(this);
};

String.prototype.isNumber = function(){
  var pattern=/^[+\-]?\d+(.\d+)?$/;
  flag=pattern.test(this);
  if(flag) return true;
  return false;

String.prototype.isNumber = function (){
    var str = this;
    return !isNaN(str);

String.prototype.isNumber = function()
  return (/^\d+$/.test(this.Trim()));