Question

在Node.js和Coffeescript中，我定义了一个类Connector，它继承自Node的EventEmitter。

我想定义Connector的子类，名为Foo。当我尝试定义Foo的新实例时，我会收到：TypeError: Cannot read property 'prototype' of undefined。

我认为这是因为我没有在我的Connector中导出module.exports类，但我如何导出_.tap()函数，以及Connector其他类可以作为要扩展的父类使用吗？

# connectors.coffee
{ EventEmitter } = require 'events'
FS               = require 'fs'
Q                = require 'q'
_                = require 'underscore'
logger           = require './logger'

class Connector extends EventEmitter
  constructor: (@credential) ->

  name : 'Unnamed Connector'
  group: undefined

  search: (query) ->
    @_search(query)
    this

  _results: (results) ->
    @emit 'results', results

  _end: ->
    @emit 'end'

  _error: (error) ->
    @emit 'error', error

  module.exports = _.tap {}, (connectors) ->
    FS.readdirSync("#{__dirname}/connectors").forEach (file) ->
      # some logic


# foo.coffee
Connector = require '../connectors'
logger    = require '../logger'

class Foo extends Connector
  constructor: ->

  name: "test_connector"

  _search: (query) ->
    logger.info "Foo connector queried: #{query}"
    logger.info "Returning fake results, stand by"

module.exports = Foo

Answer 1

那可以这样做（顺序很重要）：

module.exports = _.tap {}, (connectors) ->
  #
  # your logic here
  #

module.exports.Connector = Connector

#i_use_tap.coffee
tapFunctionResult = require('../connectors')

#foo.coffee
Connector = require('../connectors').Connector
class Foo extends Connector

Node.js + Coffeescript类具有多个导出的继承？

1 个答案: