* successfully cancelled step will immediately start closing all objects captured for later closing
 * by it and by its input steps.
 *
 * <h3>Ending a pipeline</h3>
 *
 * Each {@code ClosingFuture} pipeline must be ended. To end a pipeline, decide whether you want to
 * close the captured objects automatically or manually.
 *
 * <h4>Automatically closing</h4>
 *

appearing and vanishing so suddenly:  you make one quite giddy.'

  `All right,' said the Cat; and this time it vanished quite slowly,
beginning with the end of the tail, and ending with the grin,
which remained some time after the rest of it had gone.

  `Well!  I've often seen a cat without a grin,' thought Alice;
`but a grin without a cat!  It's the most curious thing I ever
saw in my life!'

 * successfully cancelled step will immediately start closing all objects captured for later closing
 * by it and by its input steps.
 *
 * <h3>Ending a pipeline</h3>
 *
 * Each {@code ClosingFuture} pipeline must be ended. To end a pipeline, decide whether you want to
 * close the captured objects automatically or manually.
 *
 * <h4>Automatically closing</h4>
 *