code: function(index){
      
          //check for out-of-bounds values
          if (index > -1 && index < this._length){
          
              var current = this._head,
                  i = 0;
                  
              //special case: removing first item
              if (index === 0){
                  this._head = current.next;
                  
                  /*
                   * If there's only one item in the list and you remove it,
                   * then this._head will be null. In that case, you should
                   * also set this._tail to be null to effectively destroy
                   * the list. Otherwise, set the previous pointer on the new
                   * this._head to be null.
                   */
                  if (!this._head){
                      this._tail = null;
                  } else {
                      this._head.prev = null;
                  }
         
              //special case: removing last item
              } else if (index === this._length -1){
                  current = this._tail;
                  this._tail = current.prev;
                  this._tail.next = null;
              } else {
          
                  //find the right location
                  while(i++ < index){
                      current = current.next;            
                  }
              
                  //skip over the item to remove
                  current.prev.next = current.next;
                  current.next.prev = current.prev;
              }
          
              //decrement the length
              this._length--;
          
              //return the value
              return current.data;            
          
          } else {
              return null;
          }
                 
      
      }
docs: Removes the item from the given location in the list.
  @param {int} index The zero-based index of the item to remove.
  @return {variant} The data in the given position in the list or null if
  the item doesn't exist.
  @method remove