import Emitter from 'events';
export interface listener<T> {
    (data: T): void;
}
export declare const off: <T>(emitter: Emitter, eventName: string, listener: listener<T>) => void;
export declare const emit: <T>(emitter: Emitter, eventName: string, data: T) => boolean;
export declare const setMaxListeners: (emitter: Emitter, n: number) => void;
export declare const on: <T>(emitter: Emitter, eventName: string, listener: listener<T>) => () => void;