import { Handler } from '../EventEmitter';
export interface Eventable {
    /**
     * Emits an event for target
     * @param eventName  The name of the event to publish
     * @param event      Optionally pass an event data object to the handler
     */
    emit(eventName: string, event: any): void;
    /**
     * Subscribe an event handler to a particular event name, multiple handlers per event name are allowed.
     * @param eventName  The name of the event to subscribe to
     * @param handler    The handler callback to fire on this event
     */
    on(eventName: string, handler: Handler<any>): void;
    /**
     * Unsubscribe an event handler(s) from an event. If a specific handler
     * is specified for an event, only that handler will be unsubscribed.
     * Otherwise all handlers will be unsubscribed for that event.
     * @param eventName  The name of the event to unsubscribe
     * @param handler    Optionally the specific handler to unsubscribe
     */
    off(eventName: string, handler?: Handler<any>): void;
    /**
     * Once listens to an event once then auto unsubscribes from that event
     * @param eventName The name of the event to subscribe to once
     * @param handler   The handler of the event that will be auto unsubscribed
     */
    once(eventName: string, handler: Handler<any>): void;
}