pub fn is_unsubscribe(requested: Duration) -> boolExpand description
Whether a SUBSCRIBE is asking to end the subscription rather than to have one (§3.1.1).
“A SUBSCRIBE request with an ‘Expires’ of 0 constitutes a request to unsubscribe from the matching subscription.” It is not a degenerate subscription of no duration — the notifier still owes a terminating NOTIFY (§4.2.1.4), which is the part that is easy to miss.