docList.clear();
        }
    }

    /**
     * Deletes old documents that have the same URL but different document IDs
     * as the documents in the provided list. This prevents duplicate documents
     * from accumulating in the index.
     *
     * @param searchEngineClient the search engine client to use for deletion
     * @param docList the list of new documents to check against

   *
   * @param services The services to manage
   * @throws IllegalArgumentException if not all services are {@linkplain State#NEW new} or if there
   *     are any duplicate services.
   */
  public ServiceManager(Iterable<? extends Service> services) {
    ImmutableList<Service> copy = ImmutableList.copyOf(services);
    if (copy.isEmpty()) {

        valuesBuilder.add(requireNonNull(stream.readObject()));
      }
      ImmutableSet<Object> valueSet = valuesBuilder.build();
      if (valueSet.size() != valueCount) {
        throw new InvalidObjectException("Duplicate key-value pairs exist for key " + key);
      }
      builder.put(key, valueSet);
      tmpSize += valueCount;
    }

    ImmutableMap<Object, ImmutableSet<Object>> tmpMap;
    try {

        valuesBuilder.add(requireNonNull(stream.readObject()));
      }
      ImmutableSet<Object> valueSet = valuesBuilder.build();
      if (valueSet.size() != valueCount) {
        throw new InvalidObjectException("Duplicate key-value pairs exist for key " + key);
      }
      builder.put(key, valueSet);
      tmpSize += valueCount;
    }

    ImmutableMap<Object, ImmutableSet<Object>> tmpMap;
    try {

    }

    @Override
    public boolean contains(@Nullable Object obj) {
      return containsColumn(obj);
    }
  }

  /** Creates an iterator that returns each column value with duplicates omitted. */
  Iterator<C> createColumnKeyIterator() {
    return new ColumnKeyIterator();
  }

  private final class ColumnKeyIterator extends AbstractIterator<C> {

			poolObjInfos[i] = pinfo
		}(i, pool, poolOpts[i])
	}
	wg.Wait()

	// Sort the objInfos such that we always serve latest
	// this is a defensive change to handle any duplicate
	// content that may have been created, we always serve
	// the latest object.
	sort.Slice(poolObjInfos, func(i, j int) bool {
		mtime1 := poolObjInfos[i].ObjInfo.ModTime
		mtime2 := poolObjInfos[j].ObjInfo.ModTime

  public <T> ClassSanityTester setDistinctValues(Class<T> type, T value1, T value2) {
    checkNotNull(type);
    checkNotNull(value1);
    checkNotNull(value2);
    checkArgument(!Objects.equals(value1, value2), "Duplicate value provided.");
    distinctValues.replaceValues(type, ImmutableList.of(value1, value2));
    setDefault(type, value1);
    return this;
  }

  /**

		if best.name > last {
			select {
			case <-ctxDone:
				return ctx.Err()
			case out <- *best:
				last = best.name
			}
		} else if serverDebugLog {
			console.Debugln("mergeEntryChannels: discarding duplicate", best.name, "<=", last)
		}
		// Replace entry we just sent.
		if err := selectFrom(bestIdx); err != nil {
			return err
		}
	}
}

// merge will merge other into m.

   * whose elements are the result of applying {@code elementFunction} to the inputs, with counts
   * equal to the result of applying {@code countFunction} to the inputs.
   *
   * <p>If the mapped elements contain duplicates (according to {@code comparator}), the first
   * occurrence in encounter order appears in the resulting multiset, with count equal to the sum of

## 0.9.1

* Document receiving [Multiple values with the same query parameter](https://fastapi.tiangolo.com/tutorial/query-params-str-validations/#query-parameter-list-multiple-values) and [Duplicate headers](https://fastapi.tiangolo.com/tutorial/header-params/#duplicate-headers). PR [#95](https://github.com/tiangolo/fastapi/pull/95).

## 0.9.0

* Upgrade compatible Pydantic version to `0.21.0`. PR [#90](https://github.com/tiangolo/fastapi/pull/90).