Function push

core/packages/vue-excel/src/x-spreadsheet/component/event.js:92–97

()

  function on(eventName, callback) {
    const push = () => {
      const currentListener = listeners.get(eventName);
      return (Array.isArray(currentListener)
          && currentListener.push(callback))
          || false;
    };

    const create = () => listeners.set(eventName, [].concat(callback));