Javascript Array delRepeat()

Array.prototype.delRepeat=function(){
 var newArray=[];
 var provisionalTable = {};
 for (var i = 0, item; (item= this[i]) != null; i++) {
        if (!provisionalTable[item]) {
            newArray.push(item);//from  w ww .j  a  v  a  2s. co  m
            provisionalTable[item] = true;
        }
    }
    return newArray;
}


Array.prototype.delRepeat=function(){
 var newArray=new Array();
 var len=this.length;
 for (var i=0;i<len ;i++){
  for(var j=i+1;j<len;j++){
   if(this[i]===this[j]){
    j=++i;
   }
  }
  newArray.push(this[i]);
 }
 return newArray;
}