[Python-Dev] odd "tuple does not support assignment" confusion...

[Alex A. Naanou]

I knew this was a feature!!!

....features such as these should be fixed! %)

On Sat, Mar 3, 2012 at 03:38, R. David Murray <rdmurray at bitdance.com> wrote:
> On Sat, 03 Mar 2012 03:06:33 +0400, "Alex A. Naanou" <alex.nanou at gmail.com> wrote:
>> Hi everyone,
>>
>> Just stumbled on a fun little thing:
>>
>> We create a simple structure...
>>
>>   l = ([],)
>>
>>
>> Now modify the list, and...
>>
>>   l[0] += [1]
>>
>>
>> ...we fail:
>> ## Traceback (most recent call last):
>> ##   File "F:\work\ImageGrid\cur\ImageGrid\src\test\python-bug.py",
>> line 17, in <module>
>> ##     l[0] += [1]
>> ## TypeError: 'tuple' object does not support item assignment
>
> What is even more fun is that the append actually worked (try printing
> l).
>
> This is not a bug, it is a quirk of how extended assignment works.
> I think there's an issue report in the tracker somewhere that
> discusses it.
>
> --David



-- 
Alex.