docs: function set (obj, key, val) {
  	  if (Array.isArray(obj)) {
  	    obj.splice(key, 1, val);
  	    return val
  	  }
  	  if (hasOwn(obj, key)) {
  	    obj[key] = val;
  	    return
  	  }
  	  var ob = obj.__ob__;
  	  if (obj._isVue || (ob && ob.vmCount)) {
  	    "development" !== 'production' && warn(
  	      'Avoid adding reactive properties to a Vue instance or its root $data ' +
  	      'at runtime - declare it upfront in the data option.'
  	    );
  	    return
  	  }
  	  if (!ob) {
  	    obj[key] = val;
  	    return
  	  }
  	  defineReactive$$1(ob.value, key, val);
  	  ob.dep.notify();
  	  return val
  	}