JS实现self的resend

ECMA V5定义了一个期待已久的方法：Object.getPrototypeOf，它可以无视型别信息得到某对象的原型（[[prototype]]），基于此，我们可以构造出一个resend：（请用Chrome 5、IE9预览第三版测试）

obj.resend = function() { 
var pof = Object.getPrototypeOf; 
var has = function() {......} // hasOwnProperty的封装 
var make = function(obj, old) { 
return function(name, args) { 
var step = pof(obj), 
r; 
while (step && !has(step, name)) step = pof(step); 
if (!step) throw new Error('Unable to resend: method missing'); var foundMethod = step[name]; 
var backup = arguments.callee; 
this.resend = make(this, backup); 
r = foundMethod.apply(this, Array.prototype.slice.call(arguments, 1)); 
this.resend = old; 
return r 
} 
}; 
return function(name, args__) { 
var rv; 
var old = this.resend; 
this.resend = make(this, old); 
rv = this.resend.apply(this, arguments); 
this.resend = original; 
return rv; 
} 
}()