[Python-ideas] Updated PEP 428 (pathlib)

Devin Jeanpierre jeanpierreda at gmail.com
Wed Mar 6 23:49:00 CET 2013

On Wed, Mar 6, 2013 at 5:40 PM, MRAB <python at mrabarnett.plus.com> wrote:
> If there aren't capture groups, then you can use a DFA.

You can use a variant of DFA even if there are capture groups, it just
takes more effort.

> The re and regex modules use NFA because of the various other features
> required.

I take it you mean that both the re and regex modules use backtracking search.

I was asking whether or not it can reach the exponential time
worst-case on regexps without capture groups. If the answer is no, as
you seem to be implying, then how does it prevent a DOS attack?

-- Devin

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