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From: Devin Jeanpierre <jeanpierreda@gmail.com>
Date: Wed, 2 Jul 2014 01:11:57 -0700
Subject: Re: Get named groups from a regular expression
To: Chris Angelico <rosuav@gmail.com>
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On Tue, Jul 1, 2014 at 8:58 AM, Chris Angelico <rosuav@gmail.com> wrote:
> On Wed, Jul 2, 2014 at 1:29 AM, Peter Otten <__peter__@web.de> wrote:
>> Easy, just write a regular expression to parse regular expressions ;)
>
> Hmm, is that even possible? AIUI you can't make a regex that correctly
> parses nested tokens, and named groups can definitely be nested.

Nesting isn't inherently a problem. Since nesting doesn't change the
way they parse, you can ignore nesting for the purposes of pulling out
named groups. Find each unescaped "(?P<...>".

(Making sure they are unescaped is annoying, though.)

-- Devin