Javascript Date fromISO(s)

/* formatted ISO 8601 timestrings-

2010-06-21T10:41:37.132-04:00/*from  w w  w  .  j  a v a 2s .  co  m*/
2010-06-21T14:41:37Z
2010-06-21
*/
Date.prototype.fromISO= function(s){
 var day, tz, rx=  /^(\d{4}\-\d\d\-\d\d([tT][\d:\.]*)?)([zZ]|([+\-])(\d\d):(\d\d))?$/, p= rx.exec(s) || [];
 if(p[1]){
  day= p[1].split(/\D/).map(function(itm){
   return parseInt(itm, 10) || 0;
  });
  day[1]-= 1;
  day= new Date(Date.UTC.apply(Date, day));
  if(!day.getDate()) return NaN;
  if(p[5]){
   tz= parseInt(p[5], 10)*60;
   if(p[6]) tz += parseInt(p[6], 10);
   if(p[4]== "+") tz*= -1;
   if(tz) day.setUTCMinutes(day.getUTCMinutes()+ tz);
  }
  return day;
 }
 return NaN;
}
if(![].map){
 Array.prototype.map= function(fun, scope){
  var L= this.length, A= Array(this.length), i= 0, val;
  if(typeof fun== 'function'){
   while(i< L){
    if(i in this){
     A[i]= fun.call(scope, this[i], i, this);
    }
    ++i;
   }
   return A;
  }
 }
}