Why regular expression's "non-capturing" group is not working

Posted by Jim Horng on Stack Overflow See other posts from Stack Overflow or by Jim Horng
Published on 2010-04-24T02:48:14Z Indexed on 2010/04/24 3:03 UTC
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python

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regex

In my snippet below, the non-capturing group "(?:aaa)" should be ignored in matching result, so the result should be "_bbb" only.
However, I get "aaa_bbb" in matching result; only when I specify group(2) does it show "_bbb".

import re

string1 = "aaa_bbb"
print(re.match(r"(?:aaa)(_bbb)", string1).group())

>>> aaa_bbb

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