Question

When creating a new object, you are able to reference any member of the object class. For example:

var obj = new Object();
obj["watch"];  //returns the watch() function of Object

Is there a way to override this default behavior so that obj[“watch”] returns undefined instead? Note that I only see this behavior in Firefox

Answer 1

Since EcmaScript 5.1, you can generate objects without a prototype (and without Object.protoype) this way:

var empty = Object.create(null);
empty.watch; // undefined

You will need the native function, the simple polyfill that utilizes new is not capable of doing this. See also this docs section of es5-shim.

Note that I only see this behavior in Firefox

That’s because watch is a non-standard FF extension. You should be able to obtain the standard properties in other browsers as well, though.