untilunitl is a very simple helper object that helps on waiting multiple EventEmitter. It is an EventEmitter itselt, and it waits for all the EventEmitter firing success events, or one of them firing failure event.
The APIs are
var waitings = new require('until').Waitings(); waitings.add(EventEmitter e, Array or String success events, Array or String fail events, Array or String notification events)
var waitings = new until.Waitings(); waitings.add(emitter, // The emitter object ['ok', 'done'], // A list of event names that stand for success. ['bad', 'fail'], // A list of event names that stand for failure. ['progress']); // A list of event names will continuously send.