import { EventData, EventEmitterInterface, EventHandler } from './types';
export declare class EventEmitter implements EventEmitterInterface {
    private handlers;
    on<T extends EventData = EventData>(eventName: string, handler: EventHandler<T>): () => void;
    off<T extends EventData = EventData>(eventName: string, handler: EventHandler<T>): void;
    emit<T extends EventData = EventData>(eventName: string, data?: T): void;
    once<T extends EventData = EventData>(eventName: string, handler: EventHandler<T>): () => void;
    listenerCount(eventName: string): number;
    clear(): void;
}