can stringToProxy return nil pointer?

It looks like exceptions get thrown when this function doesn't work. Is there any situation where an exception would not get thrown, however the function returns a nil pointer?

i.e. is this accurate?

ObjectPrx base = communicator()->stringToProxy("...");
assert(base);

Thank you

It would return null if you pass it an empty string, i.e., the string representation of a null proxy is an empty string.