abstract fun once(event: String, listener: Function<*>): AutoUpdater
abstract fun once(event: String, listener: (Error) -> Unit): AutoUpdater
abstract fun once(event: String, listener: Function<*>): AutoUpdater
abstract fun once(event: String, listener: (event: Event, releaseNotes: String, releaseName: String, releaseDate: Date, updateURL: String) -> Unit): AutoUpdater
abstract fun once(event: String, listener: Function<*>): AutoUpdater
Overrides EventEmitter.once