Good catch on issue 1647489 Matthew; it looks like this is where that
bug fix will end up going.  But, I am unsure if the solution for this
issue is going to be the same as for 3262.  I think the solution here is
to add an internal flag that will keep track of whether the current
character had previously participated in a Zero-Width match and thus not
allow any subsequent zero-width matches associated beyond the first, and
at the same time not consuming any characters in a Zero-width match.

Thus, I have allocated this fix as Item 24, but it may be later merged
with 22 if the solutions turn out to be more or less the same, likely
via a 22+24 thread.  The main difference, though, as I see it, is that
the change in 24 may be considered a bug where the general consensus of
22 is that it is more of a feature request and given Guido's acceptance
of a flag-based approach, I suggest we allocate re.ZEROWIDTH, re.Z and
(?z) flags to turn on the behaviour you and I expect, but still think
that be best as a 2.7 / 3.1 solution.  I would also like to add a from
__futurue__ import ZeroWidthRegularExpressions or some such to make this
the default behaviour so that by version 3.2 it may indeed be considered
the default.

Anyway, I've allocated all the new items in the launchpad repository so
feel free to go to http://www.bazaar-vcs.org/ and install Bazaar for
windows so you can download any of the individual item development
threads and try them out for yourself.  Also, please consider setting up
a free launchpad account of your very own so that I can perhaps create a
group that would allow us to better share development.

Thanks again Matthew for all your greatly appreciated contributions!