import Subscription from './Subscription';
export default class PersistentEvent<PayloadType> {
    private canceled;
    private isAccumulating;
    private listeners;
    private completedListeners;
    private resolve?;
    private reject?;
    private mayCancelAfterCallback;
    promise: Promise<void>;
    constructor(listeners: Subscription<PayloadType>[], payload?: PayloadType, mayCancelAfterCallback?: boolean);
    private completeCallback;
    cancel(): void;
}