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From: Devin Jeanpierre <jeanpierreda@gmail.com>
Date: Tue, 14 Feb 2012 10:53:38 -0500
Subject: Re: re module: Nothing to repeat, but no sre_constants.error: nothing to repeat ?
To: Vlastimil Brom <vlastimil.brom@gmail.com>
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On Tue, Feb 14, 2012 at 10:05 AM, Vlastimil Brom
<vlastimil.brom@gmail.com> wrote:
> However, is there any realistic usecase for repeated zero-width anchors?

Maybe. There is a repeated zero-width anchor is used in the Python re
test suite, which is what made me notice this. I assume that came from
some actual use-case. (see:
http://hg.python.org/cpython/file/096e856a01aa/Lib/test/test_re.py#l599
)

And yeah, even something as crazy as ()* works, but as soon as it
becomes (a*)* it doesn't work. Weird.

-- Devin