On Fri, 29 Oct 2010 21:24:23 +1300, Gregory Ewing wrote: > John Nagle wrote: >> On 10/21/2010 2:51 PM, Chris Rebert wrote: > >>> This is a common newbie stumbling-block: Don't use lists (or anything >>> mutable) as default argument values > >> That really should be an error. > > No, it shouldn't. The criterion isn't whether the object is mutable, but > whether you actually mutate it. If you treat it as read-only, there's no > problem.
And how does Python know whether some arbitrary default object is mutable or not? > Since not all Python data types have immutable variants, sometimes it's > necessary to do this. And sometimes you want the behaviour as it is. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
