Hi,

In message "Re: Oppinions on RCR for dup on immutable classes"
    on Sat, 17 Feb 2007 01:45:17 +0900, Stefan Rusterholz <apeiros / gmx.net> writes:

|> Seconded.  It pretty trivial for us core developers to make dup for
|> immutable objects to return themselves, but _I_ don't understand why
|> it is needed.  I assume obj.object_id != obj.dup.object_id, and see no
|> good reason enough to break the assumption.

|That's why I have 2 suggestions. The issue arises when you don't know 
|what you dup.

But your other suggestion was just removing dup altogether, right?  In
that case, I see no fundamental difference from the current behavior
that raises TypeError with message "can't dup" rather than
NoMethodError.  Exception handling is your friend.

							matz.