Need ability to conditionally cancel events

From W3C XForms Group Wiki (Public)

We have the ability to conditionally dispatch events, but no ability to conditionally cancel them.

For example, what if I want to conditionally cancel a rebuild, recalculate, revalidate, or refresh event. Or if we add another event to represent receiving the result of a submission, then its default processing would complete tasks like instance replacement. It would be nice to cancel that event.