anchor.diff:  
   $dart$core.Object times([$dart$core.Object x, $dart$core.Object y]) => $package$times(x, y);
   
  -Tuple $package$unzip([Iterable tuples]) => new Tuple.$withList([tuples.map(new dart$Callable(([Tuple tuple]) => tuple.first)), tuples.map(new dart$Callable(([Tuple tuple]) => tuple.rest))], null);
  +Tuple $package$unzip([Iterable tuples]) => new Tuple.$withList([tuples.map(new dart$Callable(([Tuple tuple]) => tuple.first)), tuples.map(new dart$Callable(([Tuple tuple]) => tuple.rest))]);
   
   Tuple unzip([Iterable tuples]) => $package$unzip(tuples);
   
  -Tuple $package$unzipPairs([Iterable pairs]) => new Tuple.$withList([pairs.map(new dart$Callable(([Tuple pair]) => pair.get(Integer.instance(0)))), pairs.map(new dart$Callable(([Tuple pair]) => pair.get(Integer.instance(1))))], null);
  +Tuple $package$unzipPairs([Iterable pairs]) => new Tuple.$withList([pairs.map(new dart$Callable(([Tuple pair]) => pair.get(Integer.instance(0)))), pairs.map(new dart$Callable(([Tuple pair]) => pair.get(Integer.instance(1))))]);
   
   Tuple unzipPairs([Iterable pairs]) => $package$unzipPairs(pairs);
   
  -Tuple $package$unzipEntries([Iterable entries]) => new Tuple.$withList([entries.map(new dart$Callable(([$dart$core.Object $r$]) => ($r$ as Entry).key)), entries.map(new dart$Callable(([$dart$core.Object $r$]) => ($r$ as Entry).item))], null);
  +Tuple $package$unzipEntries([Iterable entries]) => new Tuple.$withList([entries.map(new dart$Callable(([$dart$core.Object $r$]) => ($r$ as Entry).key)), entries.map(new dart$Callable(([$dart$core.Object $r$]) => ($r$ as Entry).item))]);
   
   Tuple unzipEntries([Iterable entries]) => $package$unzipEntries(entries);
   
  
positive.code:     })();
      Tuple slice([$dart$core.int index]) => (() {
          if (Integer.instance(index).equals(Integer.instance(firstSeq.size))) {
              return new Tuple.$withList([firstSeq, secondSeq], null);
          } else {
              return Sequence.$slice(this, index);
          }
  
negative.code: 
  Iterable zipEntries([Iterable keys, Iterable items]) => $package$zipEntries(keys, items);
  
  Iterable $package$zipPairs([Iterable firstElements, Iterable secondElements]) => $package$mapPairs(new dart$Callable(([$dart$core.Object first, $dart$core.Object second]) => new Tuple.$withList([first, second])), firstElements, secondElements);
  
  Iterable zipPairs([Iterable firstElements, Iterable secondElements]) => $package$zipPairs(firstElements, secondElements);
  
  