I wanna get a "right-to-left" substitution.
See reverse. 
$d = reverse "123456789";
$d =~ s/(?<=\d)(?=(\d\d)+$)/-/g;
print scalar reverse "$d\n";

[download]
update: added obvious solution

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re: Another puzzled RegEx Problem. by shmem
in thread Another puzzled RegEx Problem. by pysome

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