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Author malin
Recipients beardypig, ezio.melotti, malin, mrabarnett, serhiy.storchaka, xtreak
Date 2019-01-21.14:34:58
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <1548081298.41.0.259852391421.issue34294@roundup.psfhosted.org>
In-reply-to
Content
Original post's bug was introduced in Python 3.7.0

When investigate the code, I found another bug about capturing groups. This bug exists since very early version.
regex module doesn't have this bug.

Python 3.4.4 (v3.4.4:737efcadf5a6, Dec 20 2015, 19:28:18) [MSC v.1600 32 bit (Intel)] on win32
>>> import re
>>> re.search(r"\b(?=(\t)|(x))x", "a\tx").groups()
('', 'x')

Expected result: (None, 'x')

Python 3.7.2 (tags/v3.7.2:9a3ffc0492, Dec 23 2018, 23:09:28) [MSC v.1916 64 bit (AMD64)] on win32
>>> import regex
>>> regex.search(r"\b(?=(\t)|(x))x", "a\tx").groups()
(None, 'x')
History
Date User Action Args
2019-01-21 14:35:00malinsetrecipients: + malin, ezio.melotti, mrabarnett, serhiy.storchaka, beardypig, xtreak
2019-01-21 14:34:58malinsetmessageid: <1548081298.41.0.259852391421.issue34294@roundup.psfhosted.org>
2019-01-21 14:34:58malinlinkissue34294 messages
2019-01-21 14:34:58malincreate