chaplinjs/chaplin — pull request #488 by andriijas (2013-03-21 16:29:13+00:00)
Title: mediator.once/Backbone.Events.once with EventBroker support

Caveat:

The current way the EventBroker works is to unsubscribe existing handlers with the same name.

So if you have one handler listening for events and then add a once handler for the same event, the handler will be unsubscribed and replaced with a once subscriber, and the other way around.

I think this is correct :)