From: Gregory Brown Date: 2007-02-17T07:28:35+09:00 Subject: Re: Oppinions on RCR for dup on immutable classes On 2/16/07, Robert Dober wrote: > On 2/16/07, Phrogz wrote: > > b) You should never ever write "a.dup rescue a" because it will give > > you strange problems if a might refer to a mutable object that doesn't > > respond to #dup. > Neve say never ;) but when you write > a.dup rescue a > you should be aware of that potential danger Right. My only point was that this solved what the OP asked for without being hard. It just seems like that solution is no better or worse than changing the behaviour of dup, except for the fact that it puts the burden of bad design into the programmer's hands, and not that of the programming language :)