text: import start from './start';
  import end from './end';
  import condition from './condition';
  import operation from './operation';
  const shapes = [start, end, condition, operation];
  const fn = {};
  /**
   * 从文件加载shape类型配置
   * 把配置类型挂载到对象的fn属性上
   * shapes  定义好的配置数组集合
   * shapes中的元素结构如下
   * {
   *     type: String, // 类型名称
   *     fn: Function // 执行函数
   * }
   */
  for (let i = 0, length = shapes.length; i < length; i++) {
      if (fn[shapes[i].type]) {
          throw new Error(`已经存在[${shapes[i].type}]类型了`);
      }
      fn[shapes[i].type] = shapes[i].fn;
  }
  export default fn;