[Python-Dev] PySequence_Check but no __len__
brett at python.org
Thu Jun 21 12:29:52 EDT 2018
Sorry, I don't quite follow.
On Thu, 21 Jun 2018 at 08:50 Christian Tismer <tismer at stackless.com> wrote:
> Hi friends,
> there is a case in the Python API where I am not sure what to do:
> If an object defines __getitem__() only but no __len__(),
> then PySequence_Check() already is true and does not care.
return s != NULL && s->ob_type->tp_as_sequence &&
s->ob_type->tp_as_sequence->sq_item != NULL;
> So if I define no __len__, it simply fails. Is this intended?
What is "it" in this case that is failing? It isn't PySequence_Check() so
I'm not sure what the issue is.
> I was mislead and thought this was the unlimited case, but
> it seems still to be true that sequences are always finite.
> Can someone please enlighten me?
> Christian Tismer-Sperling :^) tismer at stackless.com
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