I submitted the patch to make the csv module use an OrderedDict in DictReader. It doesn't, AFAIR, use anything but the ordering property of ordered dict, so the reversion to a simple dict should be perfectly OK as long as no consumers have started to make use of specific OrderedDict properties.
regards Steve Holden
On Thu, Jan 31, 2019 at 7:55 AM INADA Naoki firstname.lastname@example.org wrote:
csv.DictReader uses OrderedDict by default, from Python 3.6. But it doesn't make sense anymore, like namedtuple._asdict(). How about changing default dict type back to regular dict.
Python is widely used for handling learge data. So I think changing default dict type to OrderedDict was performance and memory usage regression in 3.6.
Additionally, configparser uses OrderedDict by default from Python 3.6 too.
I am not sure about `parser['section1'] == parser['section2']` is not used yet. But we broke it once in 3.6 by changing dict to OrderedDict. Are there any issue report caused by this backward incompatibility?
And I think performance and memory efficiency is not so important for configparser, unlike csv.
- +1 about changing csv.DictReader's default dict type
- +0.5 about changing configparser's default dict type.
How do you think?
INADA Naoki email@example.com _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/steve%40holdenweb.com