text: module.exports = createEventHub = () => ({
  hub: Object.create(null),
  emit(event, data) {
  (this.hub[event] || []).forEach(handler => handler(data));
  },
  on(event, handler) {
  if (!this.hub[event]) this.hub[event] = [];
  this.hub[event].push(handler);
  },
  off(event, handler) {
  const i = (this.hub[event] || []).findIndex(h => h === handler);
  if (i > -1) this.hub[event].splice(i, 1);
  }
  });