TypeScript: egg.Application 导出了接口而非类

[waitingsong]

• Node Version: 8.10.0
• Egg Version: 2.4.10
• Plugin Name:
• Plugin Version:
• Platform: win7
• Mini Showcase Repository:

参照 框架扩展文档
用 TS 实现提示错误：

import * as path from 'path'
import { Application as EggApplication } from 'egg'

export const EGG_PATH = Symbol.for('egg#eggPath');

export default class Application extends EggApplication {
  get [EGG_PATH]() {
    return path.dirname(__dirname);
  }
}

[waitingsong]

[waitingsong]

also error during this usage:

import * as path from 'path'
import {Agent as EggAgent} from 'egg'

export const EGG_PATH = Symbol.for('egg#eggPath');

export default class Agent extends EggAgent {
  get [EGG_PATH]() {
    return path.dirname(__dirname);
  }
}