}
      T result = output(index);
      toRemove = index;
      index++;
      return result;
    }

    @Override
    public void remove() {
      checkRemove(toRemove >= 0);
      if (counts[toRemove] > 0) {
        distinctElements--;
        size -= counts[toRemove];
        counts[toRemove] = 0;
      }
      toRemove = -1;
    }
  }

  @Override

    Multiset<String> multiset = HashMultiset.create();
    Iterable<String> toRemove = asList("a", "b", "a");
    assertFalse(Multisets.removeOccurrences(multiset, toRemove));
    assertTrue(multiset.isEmpty());
  }

  public void testRemoveOccurrencesMultisetEmpty() {
    Multiset<String> multiset = HashMultiset.create();
    Multiset<String> toRemove = HashMultiset.create(asList("a", "b", "a"));

      }

      @Override
      public void remove() {
        checkState(toRemove != null, "no calls to next() since the last call to remove()");
        LinkedHashMultimap.this.remove(toRemove.getKey(), toRemove.getValue());
        toRemove = null;
      }
    };
  }

  @Override
  Iterator<V> valueIterator() {
    return Maps.valueIterator(entryIterator());
  }

  /**

        List<Range<K>> toRemove = new ArrayList<>();
        for (Entry<Range<K>, V> entry : entrySet()) {
          if (predicate.apply(entry)) {
            toRemove.add(entry.getKey());
          }
        }
        for (Range<K> range : toRemove) {
          TreeRangeMap.this.remove(range);
        }
        return !toRemove.isEmpty();
      }

      @Override

      if (hasNext()) {
        toRemove = iterator;
        return iterator.next();
      } else {
        throw new NoSuchElementException();
      }
    }

    @Override
    public void remove() {
      if (toRemove == null) {
        throw new IllegalStateException("no calls to next() since the last call to remove()");
      }
      toRemove.remove();
      toRemove = null;
    }

        documentList.add(doc3);

        QueryResponseList qrList = new QueryResponseList(documentList, 0, 10, 0);

        Collection<Map<String, Object>> toRemove = Arrays.asList(doc2);
        assertTrue(qrList.removeAll(toRemove));
        assertEquals(2, qrList.size());
        assertFalse(qrList.contains(doc2));

        Collection<Map<String, Object>> toRetain = Arrays.asList(doc1);