what does 'a=b=c=[]' do

[Robert Kern]

On 12/23/11 10:22 AM, rusi wrote:
> On Dec 23, 2:39 pm, Steven D'Aprano<steve
> +comp.lang.pyt... at pearwood.info>  wrote:
>> On Fri, 23 Dec 2011 00:38:07 -0800, rusi wrote:
>>> Likewise function arguments that default to mutable entities is a known
>>> gotcha of python which is best treated as a bug in python.
>>
>> Nonsense. It is a feature, not a bug.
>
> Tsk Tsk How can python have a bug? And that too on the python mailing
> list?
>
> Others however feel differently. See Chris Rebert's
> http://mail.python.org/pipermail/python-ideas/2007-January/000073.html
> and the links cited there.
>
>>
>> Some people might argue that it is a mistake, a minor feature which
>> allegedly causes more difficulties than benefits. I do not hold with that
>> idea. But either way, it is not a bug to be fixed, but a deliberate
>> consequence of intended semantics.
>
> I did not ask or imply that it should be 'fixed', just that language
> misfeatures should be treated with extra care.

"Bug" means, roughly, "something that should be fixed" not just any "thing that 
has some unwanted consequences". So yes, by calling it a bug you are asking and 
implying just that. If you don't mean that, don't use the word "bug".

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco