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Date: Sun, 16 Apr 2017 15:47:56 +0200
From: Jilles Tjoelker <jilles@stack.nl>
To: Kyle Evans <kevans91@ksu.edu>
Cc: freebsd-hackers@freebsd.org
Subject: Re: Replacing libgnuregex
Message-ID: <20170416134756.GA88424@stack.nl>
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On Tue, Apr 11, 2017 at 03:20:58PM -0500, Kyle Evans wrote:
> On the other hand, I think I could fairly easily implement most of these
> into libc/regex. Here's a summary of what this option entails adding to
> libc/regex, from what I've found:

> [snip]
> * Add backreferences (\1 through \9) to EREs
> [snip]

Adding this enforces that EREs, like BREs, may sometimes require
exponential time to match. I would prefer to avoid that.

-- 
Jilles Tjoelker