type CallbackFunction<T = unknown> = (eventPayload: T) => void;
declare class EventEmitter {
    _events: Record<string, CallbackFunction[]>;
    constructor();
    on<T>(event: string, callback: CallbackFunction<T>): void;
    off(event: string, callback: CallbackFunction): void;
    emit(event: string, eventPayload?: unknown): void;
    hasListener(event: string): boolean;
}
export = EventEmitter;