Javascript CoffeeScript类扩展-TypeError:Object#<；谷歌>；没有方法'；执行'；

当我执行

class Search
  perform: (text) ->
    query = encodeURIComponent text
    results = ''
    request {uri: @uri + query }, (error, response, body) =>
      if !error? && response.statusCode == 200
        window = jsdom.jsdom(body).createWindow()
        jsdom.jQueryify window, './jquery-1.5.min.js', (window, jquery) =>
          $ = window.$
          jquery(@pattern).each (i, lmn) =>
            link = $(lmn).text() + " - " +  $(lmn).attr('href') 
            if requiresHttp? && /^http/.exec  $(lmn).attr('href')
              results = results + link + "\n"
            else
              results = results + link + "\n"
          @emit 'end', results

sys.inherits(Search, process.EventEmitter)

class Google extends Search
  @uri     = 'http://www.google.com/search?q='
  @pattern = '#ires ol li .r a'

它返回错误“TypeError:Object”#谷歌没有“perform”方法。extend不应该提供这种方法吗

更新

发布后不久，我重新考虑了代码。工作结果如下：

google = new Google
google.perform 'blah'

---

CD Sandchez的评论是正确的。如果您剪掉

sys.inherits

行，则

perform

运行

您应该做的是始终使用CoffeeScript继承：

{EventEmitter} = require "events"
request        = require 'request'
jsdom          = require 'jsdom'


class Search extends EventEmitter
  constructor: ->
    @linkPrefix   = ''
    @requiresHttp = false
    @uri          = ''
    @pattern      = ''
  perform: (text) ->
    query = encodeURIComponent text
    results = ''
    request {uri: @uri + query }, (error, response, body) =>
      if !error? && response.statusCode == 200
        window = jsdom.jsdom(body).createWindow()
        jsdom.jQueryify window, './jquery-1.5.min.js', (window, jquery) =>
          $ = window.$
          jquery(@pattern).each (i, lmn) =>
            link = $(lmn).text() + " - " + @linkPrefix + $(lmn).attr('href') 
            if @requiresHttp?
              if /^http/.exec  $(lmn).attr('href')
                results = results + link + "\n"
            else
              results = results + link + "\n"
          @emit 'end', results

class Google extends Search
  constructor: ->
    @uri          = 'http://www.google.com/search?q='
    @pattern      = '#ires ol li .r a'
    @requiresHttp = true

class Youtube extends Search
  constructor: ->
    @uri          = 'http://www.youtube.com/results?search_query='
    @pattern      = '#search-results h3 a'
    @linkPrefix   = 'http://www.youtube.com'


exports.Google  = Google
exports.Youtube = Youtube

---

它应该会起作用。也许当您从

EventEmitter

继承时，它会弄乱原型？您应该查看生成的代码。顺便说一句，您可以做的另一个更改是编写

class exports.Google

和

class exports.Youtube

，而不是单独执行

exports.Google=Google

和

exports.Youtube=Youtube

行。当然，这两种方法都有效；这只是一种风格的选择。整洁-我会试一试，谢谢。是的，事实证明这是问题的一部分。无论出于什么原因，我从未收到有人回复的电子邮件通知。不过，谢谢！

class Search extends process.EventEmitter