将模块模式与Prototype相结合(Combining Module pattern with Prototype)

 我试图通过使用模块模式封装一些方法。 我也试图通过使用原型来避免新对象创建的新函数定义。 问题是我必须实现一个构造函数，我无法弄清楚如何。 我的代码： 
 
 // constructor
function Anagram(original) {
  this.original = original.toLowerCase()
  this.sortedOriginal = this.sort(this.original)
}

// prototype as a module
Anagram.prototype = (function() {
  function isAnagram(word) {
    word = word.toLowerCase()
    return this.original != word && sameLetters(word)
  }
  function sameLetters(word) {
    return this.sortedOriginal === sort(word)
  }
  function sort(str) {
    return str.split('').sort().join('')
  }
  return {
    match: function(words) {
      return words.filter(isAnagram, this)
    }
  }
}())

module.exports = Anagram
 
 运行 
 
Anagram.new('ant').match(['tan', 'stand', 'at'])
 
 失败了 
 
TypeError: Object #<Object> has no method 'sort'
 
 我理解为什么， sort没有在构造函数中定义。 我该如何解决？ 

I am trying to encapsulate some methods by using module pattern. I am also trying to avoid new function definitions on new object creation by using a prototype. The problem is I have to implement a constructor and I couldn't figure how. My code:
 
 // constructor
function Anagram(original) {
  this.original = original.toLowerCase()
  this.sortedOriginal = this.sort(this.original)
}

// prototype as a module
Anagram.prototype = (function() {
  function isAnagram(word) {
    word = word.toLowerCase()
    return this.original != word && sameLetters(word)
  }
  function sameLetters(word) {
    return this.sortedOriginal === sort(word)
  }
  function sort(str) {
    return str.split('').sort().join('')
  }
  return {
    match: function(words) {
      return words.filter(isAnagram, this)
    }
  }
}())

module.exports = Anagram
 
Running
 
Anagram.new('ant').match(['tan', 'stand', 'at'])
 
Fails with 
 
TypeError: Object #<Object> has no method 'sort'
 
And I understand why, sort is not defined in the constructor. How can I fix it?

原文：https://stackoverflow.com/questions/21191599