On Wed, Apr 30, 2008 at 12:41 PM, Guido van Rossum
<report@bugs.python.org> wrote:
>
>  Guido van Rossum <guido@python.org> added the comment:
>
>  > ..  builtin_next() should return
>  > NULL without an exception set and thus trigger a SystemError.
>
>  Wrong; the iternext slot is designed to return NULL without setting an
>  exception.  See e.g. listiter_next().

I did not know that.  Thanks for the explanation.  In this case,
wouldn't it be cleaner to call PyIter_Next which is documented to
return NULL with no exception?