In python you can define a object having __getattr__(self,key) method to handle all unknown attributes to be solvable in programmatic manner, but in javascript you can only define getters and setters for pre-defined attributes. Is there a generic way of getting the former thing done also in javascript?

Sample code would be smth like:

function X() {};

X.prototype={

  __getattr__:function(attrname) {

    return Value for attribute '+attrname+';

  }

}



x=new X()

alert(x.lskdjoau); // produces message: Value of attribute 'lskdjoau'

Key point is getting value of attribute programmatically depending on the name of the attribute. Pre-setting attribute does not help because during init there is no information what attributes might be requested.