// We need to test with two input futures since ExecutionList.execute
    // doesn't catch Errors and we cannot depend on the order that our
    // transformations run. (So it is possible that the Error being thrown
    // could prevent our second transformations from running).
    SettableFuture<Integer> exceptionInput = SettableFuture.create();
    ListenableFuture<Integer> exceptionComposedFuture =

    // We need to test with two input futures since ExecutionList.execute
    // doesn't catch Errors and we cannot depend on the order that our
    // transformations run. (So it is possible that the Error being thrown
    // could prevent our second transformations from running).
    SettableFuture<Integer> exceptionInput = SettableFuture.create();
    ListenableFuture<Integer> exceptionComposedFuture =

            ClosingFunction<? super V, U> transformation, @ParametricNullness V input)
            throws Exception {
      // TODO(dpb): Consider ways to defer closing without creating a separate CloseableList.
      CloseableList newCloseables = new CloseableList();
      try {
        return immediateFuture(transformation.apply(newCloseables.closer, input));
      } finally {

    return new TransformedEntriesNavigableMap<>(fromMap, transformer);
  }

  /**
   * A transformation of the value of a key-value pair, using both key and value as inputs. To apply
   * the transformation to a map, use {@link Maps#transformEntries(Map, EntryTransformer)}.
   *
   * @param <K> the key type of the input and output entries