docs: function(itemSet, symbol){
  
              var self = this,
                  gotoItemSet = new DataTypes.ItemSet();
  
              _.each(itemSet.subItems, function(item){
                  if(item.dotSymbol === symbol){
                      gotoItemSet.push(new DataTypes.Item(item.production, item.dotPosition+1, item.lookaheads));
                  }
              });
  
              return gotoItemSet;
          }