Node.js和ES6中的module.exports与export默认

Node module.exports和ES6 之间有什么区别export default？我试图弄清楚为什么export default在Node.js 6.2.2中尝试出现“ __不是构造函数”错误。

什么有效

'use strict'
class SlimShady {
  constructor(options) {
    this._options = options
  }

  sayName() {
    return 'My name is Slim Shady.'
  }
}

// This works
module.exports = SlimShady

什么不工作

'use strict'
class SlimShady {
  constructor(options) {
    this._options = options
  }

  sayName() {
    return 'My name is Slim Shady.'
  }
}

// This will cause the "SlimShady is not a constructor" error
// if in another file I try `let marshall = new SlimShady()`
export default SlimShady