Function.prototype._makeLikeNative.js

Function.prototype._makeLikeNative = function()
{
  if(Object.defineProperty)
  {
    var blackLabelProp = 
    {
      enumerable: false,
      configurable: false,
      writable: false,
      value: true 
    };

    Function.prototype._makeLikeNative = function()
    {
      Object.defineProperty(this, 'isSourceHided', blackLabelProp);
    };

    var _oldFnToString = Function.prototype.toString;
    
    Object.defineProperty(Function.prototype, 'toString',
      {
        configurable: false,
        writable: false,
        value: function()
        {
          if(this.isSourceHided === true)
            return 'function () { [native code] }';
            
          return _oldFnToString.call(this);  
        }
      }
    );

    Function.prototype.toString._makeLikeNative();
  }
  else
  {
    var _hider = function()
    {
      return 'function () { [native code] }';
    }; 

    _hider.toString = _hider;

    Function.prototype._makeLikeNative = function()
    {
      // also dont remember that IE do not enum valueOf and toString properties :P
      this.toString = _hider;
    };
  }
  
  Function.prototype._makeLikeNative._makeLikeNative();
  
  this._makeLikeNative();
};