5.13 Discarding Deferred Event Objects
A potential issue arises where deferred event objects are returned from method calls that are part of a higher level API. There may be situations where the caller just wants to initiate a transaction and is not concerned with processing the returned callbacks. If the returned deferred event object is allowed to go out of scope without being correctly terminated, a warning will be appended to the reactor logs on object finalisation.
To prevent the generation of these warning messages in the reactor logs, the deferred event object may be explicitly discarded by calling the discard method on the Deferred interface. This has the effect of terminating the callback chain with an implicit `empty' terminal deferrable.