export type ESMitterEventName = string | symbol;
export interface ESMitterEvent<EventArguments extends unknown[], EventContext = undefined> {
    arguments: EventArguments;
    fn: (this: EventContext, ...args: EventArguments) => void;
    context: EventContext;
}
export interface ESMitterEvents {
    [key: ESMitterEventName]: ESMitterEvent<any[], any>;
}
export declare class ESMitter<Events extends ESMitterEvents> {
    private events;
    private eventsCount;
    constructor();
    /**
     * Add a listener for a given event.
     *
     * @param {(String|Symbol)} event The event name.
     * @param {Function} fn The listener function.
     * @param {*} context The context to invoke the listener with.
     * @param {Boolean} once Specify if the listener is a one-time listener.
     * @returns {EventEmitter}
     */
    addListener<EventName extends keyof Events>(event: EventName, fn: Events[EventName]["fn"], context?: ESMitterEvents[EventName]["context"], once?: boolean): this;
    /**
     * Clear event by name.
     *
     * @param {(String|Symbol)} event The Event name.
     */
    private clearEvent;
    /**
     * Return an array listing the events for which the emitter has registered
     * listeners.
     *
     * @returns {Array}
     */
    eventNames(): ESMitterEventName[];
    /**
     * Return the listeners registered for a given event.
     *
     * @param {(String|Symbol)} event The event name.
     * @returns {Array} The registered listeners.
     */
    listeners<EventName extends keyof Events>(event: EventName): (() => unknown)[];
    /**
     * Return the number of listeners listening to a given event.
     *
     * @param {(String|Symbol)} event The event name.
     * @returns {Number} The number of listeners.
     */
    listenerCount<EventName extends keyof Events>(event: EventName): number;
    /**
     * Calls each of the listeners registered for a given event.
     *
     * @param {(String|Symbol)} event The event name.
     * @returns {Boolean} `true` if the event had listeners, else `false`.
     */
    emit<EventName extends keyof Events>(event: EventName, ...args: Events[EventName]["arguments"]): boolean;
    /**
     * Add a listener for a given event.
     *
     * @param {(String|Symbol)} event The event name.
     * @param {Function} fn The listener function.
     * @param {*} [context=this] The context to invoke the listener with.
     * @returns {EventEmitter} `this`.
     */
    on<EventName extends keyof Events>(event: EventName, fn: Events[EventName]["fn"], context?: Events[EventName]["context"]): this;
    /**
     * Add a one-time listener for a given event.
     *
     * @param {(String|Symbol)} event The event name.
     * @param {Function} fn The listener function.
     * @param {*} [context=this] The context to invoke the listener with.
     * @returns {EventEmitter} `this`.
     */
    once<EventName extends keyof Events>(event: EventName, fn: Events[EventName]["fn"], context?: Events[EventName]["context"]): this;
    /**
     * Remove the listeners of a given event.
     *
     * @param {(String|Symbol)} event The event name.
     * @param {Function} fn Only remove the listeners that match this function.
     * @param {*} context Only remove the listeners that have this context.
     * @param {Boolean} once Only remove one-time listeners.
     * @returns {EventEmitter} `this`.
     */
    removeListener<EventName extends keyof Events>(event: EventName, fn?: Events[EventName]["fn"], context?: Events[EventName]["context"], once?: boolean): this;
    /**
     * Remove the listeners of a given event. Alias of removeListener().
     *
     * @param {(String|Symbol)} event The event name.
     * @param {Function} fn Only remove the listeners that match this function.
     * @param {*} context Only remove the listeners that have this context.
     * @param {Boolean} once Only remove one-time listeners.
     * @returns {EventEmitter} `this`.
     */
    off: <EventName extends keyof Events>(event: EventName, fn?: Events[EventName]["fn"], context?: Events[EventName]["context"], once?: boolean) => this;
    /**
     * Remove all listeners, or those of the specified event.
     *
     * @param {(String|Symbol)} [event] The event name.
     * @returns {EventEmitter} `this`.
     */
    removeAllListeners<EventName extends keyof Events>(event?: EventName): this;
}