Tries to cancel the entry. Cancelation may not be possible if:
neverCancelThe promised value
If true, the entry was canceled. It may or may not have already been started.
If true, the entry was completed either successfully or not. wasStarted will always be true if wasCompleted is true.
wasCanceled will never be true if wasCompleted is true.
If true, the entry was started. It may or may not also be either canceled or completed.
An entry reference, which can be used to cancel the entry, check its status, or to get the promised value.