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我正在尝试重用 node.jsBuffer模块以在其之上创建一个改进的 Buffer 。问题是，如果我直接从它继承，我不能应用构造函数并且一些属性会丢失（因为它们没有被初始化）。上的使用EventEmitter按预期工作。

恐怕问题出在if(!(this instanceof Buffer)){}代码上，即评估为假，因为代码实际上并没有从原型继承，所以我需要一种方法来欺骗instanceof操作员以使其工作。

我正在使用 ES5 类模块https://npmjs.org/package/es5class

var Class = require('es5class');

var MyBuffer = Class.define('MyBuffer').implement(Buffer, true);

// MyBuffer.prototype.write exists
// (new MyBuffer(4)).length is undefined
// (new MyBuffer(4)).parent is undefined, etc

但EventEmitter照常工作

var Class = require('es5class');

var MyEventEmitter = Class.define('MyEventEmitter').implement(require('events').EventEmitter, true);

// MyEventEmitter.prototype.emit exists
// (new MyEventEmitter())._events is an object as expected

我正在尝试更改 ES5 类模块以使其工作，尝试覆盖constructorbefore call f.apply()，但无济于事。

// $apply is an array of mixin'd classes, for example, Buffer or EventEmitter
self.$apply.forEach(function (f){
  var oldctor = instance.constructor; // current instance constructor

  Object.defineProperty(instance, 'constructor', {
    value       : f, // trying to change it
    writable    : true,
    configurable: true,
    enumerable  : false
  });

  console.log(instance instanceof f); // false, this needs to evaluate to true just before the f.apply, how to? instance.prototype cannot "redefine" prototype

  f.apply(instance, arguments); // works the same as EventEmitter.apply(this, arguments);

  Object.defineProperty(instance, 'constructor', {
    value       : oldctor, // try to restore it
    writable    : true,
    configurable: true,
    enumerable  : false
  });
});

Bergi 在https://github.com/pocesar/ES5-Class/blob/master/index.js#L24中指出，设法用一个相当丑陋的黑客来修复它

superApply = function(instance, object, args){
  if (object.$apply.length) {
    object.$apply.forEach(function (f){
      // dirty little hack to make classes like Buffer think the prototype is instanceof itself
      spo(instance, f.prototype);
      f.apply(instance, args);
    });
  }
},
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