I'm sorry, configparser is changed already. https://bugs.python.org/issue33504 On Thu, Jan 31, 2019 at 4:52 PM INADA Naoki wrote:

Hi,

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.

I'm

* +1 about changing csv.DictReader's default dict type * +0.5 about changing configparser's default dict type.

How do you think?

Regards, -- INADA Naoki

-- INADA Naoki

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 wrote:

Hi,

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.

I'm

* +1 about changing csv.DictReader's default dict type * +0.5 about changing configparser's default dict type.

How do you think?

Regards, -- INADA Naoki _______________________________________________ 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