anchor.diff:    }
   
     static void _filter(List source,
  -                      bool test(E element),
  +                      bool test(var element),
                         bool retainMatching) {
       List retained = [];
       int length = source.length;
       for (int i = 0; i < length; i++) {
  -      E element = source[i];
  +      var element = source[i];
         if (test(element) == retainMatching) {
           retained.add(element);
         }
  
positive.code: 
    Iterable<E> skip(int count) => new SubListIterable(this, count, null);
  
    Iterable<E> skipWhile(bool test(E element)) => super.skipWhile(test);
  
    Iterable<E> take(int count) => new SubListIterable(this, 0, count);
  
    Iterable<E> takeWhile(bool test(E element)) => super.takeWhile(test);
  
    List<E> toList({ bool growable: true }) {
      List<E> result;
  
negative.code:     }
    }
  
    Iterable<E> where(bool test(E element)) => new WhereIterable<E>(this, test);
  
    Iterable map(f(E element)) => new MappedListIterable(this, f);
  
  