자바스크립트에서 함수 이름과 매개변수 메서드 인스턴스를 얻는 방법에 대한 자세한 설명

Function.prototype.getName = function(){
    return this.name || this.toString().match(/function\s*([^(]*)\(/)[1]
}

 var getFnName = function(callee){
      var _callee = callee.toString().replace(/[\s\?]*/g,""),
      comb = _callee.length >= 50 ? 50 :_callee.length;
      _callee = _callee.substring(0,comb);
      var name = _callee.match(/^function([^\(]+?)\(/);
      if(name && name[1]){
        return name[1];
      }
      var caller = callee.caller,
      _caller = caller.toString().replace(/[\s\?]*/g,"");
      var last = _caller.indexOf(_callee),
      str = _caller.substring(last-30,last);
      name = str.match(/var([^\=]+?)\=/);
      if(name && name[1]){
        return name[1];
      }
      return "anonymous"
};

function  ee(){
      //+++++++++++++++++++++++++++++++++
      var fnname =getFnName(arguments.callee)
      //+++++++++++++++++++++++++++++++++
      alert(fnname)
    };
ee();

function getFuncName(_callee)
{
 var _text = _callee.toString();
 var _scriptArr = document.scripts;
 for (var i=0; i<_scriptArr.length; i++)
 {
  var _start = _scriptArr[i].text.indexOf(_text);
  if (_start != -1)
  {
   if (/^function\s*\(.*\).*\r\n/.test(_text))
   {
    var _tempArr = _scriptArr[i].text.substr(0, _start).split(&#39;\r\n&#39;);
    return _tempArr[_tempArr.length - 1].replace(/(var)|(\s*)/g, &#39;&#39;).replace(/=/g, &#39;&#39;);
   }
   else
    return _text.match(/^function\s*([^\(]+).*\r\n/)[1];
  }
 }
}
function a()
{
 return getFuncName(arguments.callee);
}
var b = function()
{
 return getFuncName(arguments.callee);
}
window.alert(a());
window.alert(b());

function test(){
for(var i=0;i<arguments.length;i++) document.write(arguments[i]);
}