[Python-Dev] PySequence_Fast_GET_ITEM in string join

[Jeremy Hylton]

On 5/23/06, Andrew Dalke <dalke at dalkescientific.com> wrote:
> Me [Andrew Dalke] said:
> > The relevant code in stringobject uses PySequence_Fast_GET_ITEM(seq,
> > i),
> > which likely doesn't know about my derived __getitem__.
>
> Oops, I didn't know what the code was doing well enough.  The
> relevant problem is
>
>          seq = PySequence_Fast(orig, "");
>
> That calls __iter__ on my derived list object, which knows nothing
> about my overridden __getitem__

Put another way, the problem is related to your initial claim:
> I can derive from list and override __getitem__

You can do that, but you should not.  It's almost a bug that you can.

Jeremy


>
> So things are working as designed.
>
> Well, back to blundering about.  Too much brennivin. ;)
>
>                                         Andrew
>                                         dalke at dalkescientific.com
>
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