code: function urlSync(urlKeyOrTarget, property, descriptor) {
    if (invokedWithArgs(arguments)) {
      let options = property
      return (target, property, descriptor) =>
        urlsync(urlKeyOrTarget || property, { ...keyMap, ...options }, target, property, descriptor)
    }
  
    return urlsync(property, keyMap, urlKeyOrTarget, property, descriptor)
  }
docs: 用于同步状态至 URL
  @namespace urlSync
  @name urlSync
  @example
  class Model extends Root {
  \@urlSync
  \@observable sync = 'abc'
  // 未使用 @observable 修饰, urlSync会自动将其转为 observable
  \@urlSync('g')
  value = 'abcdef'
  }
  @public