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type Listener<E extends Event> = [EventListener<E>, EventOptions | undefined];
/** * Class to manage the event listeners * and dispatch events */export default class Events<E extends Event> {  listeners = new Map<string, Set<Listener<E>>>();
  /** Assign a listener to an event */  addEventListener(    type: string,    listenerFn: EventListener<E>,    options?: EventOptions,  ) {    const listeners = this.listeners.get(type) || new Set();    const listener: Listener<E> = [listenerFn, options];
    listeners.add(listener);    this.listeners.set(type, listeners);
    // Remove on abort    if (options?.signal) {      options.signal.addEventListener("abort", () => {        listeners.delete(listener);      });    }
    return this;  }
  /** Dispatch an event */  async dispatchEvent(event: E) {    const { type } = event;    const listeners = this.listeners.get(type);
    if (!listeners) {      return true;    }
    for (const listener of listeners) {      const [listenerFn, listenerOptions] = listener;
      // Remove the listener if it's a once listener      if (listenerOptions?.once) {        listeners.delete(listener);      }
      if (await listenerFn(event) === false) {        return false;      }    }
    return true;  }}
/** An event object */export interface Event {  /** The event type */  type: string;}
/** Event listener */export type EventListener<E extends Event> = (event: E) => unknown;
/** The available options for events */export interface EventOptions {  /**   * To indicate that the listener should be invoked at most once   * after being added   */  once?: boolean;
  /**   * The listener will be removed   * when the given AbortSignal object's abort() method is called   */  signal?: AbortSignal;}