Jesse arrives in 6 hours, so I'll keep this short.
Today I asked on #perl6 which one should I do first: Perl 5 regex (via PCRE), or a Perl 6 to C compiler (via Template Haskell)? pjcj suggested that the former is more practical, so I went with it. I'm glad to report that it now works, with full $/ as arrayref and $0 $1 $2 etc capturing magic.
The beginning of RRegex.hs in Pugs now reads:
A king he was on carven throne In many-pillared halls of stone With golden roof and silver floor, And runes of power upon the door...
To wit:
pugs> "(balanced)" ~~ rx:perl5{^(\()?[^()]+(?(1)\))$};
bool::true
pugs> "(unbalanced" ~~ rx:perl5{^(\()?[^()]+(?(1)\))$};
bool::false
Much thanks to John Meacham of hs-regex and Philip Hazel of PCRE for their excellent libraries. Now the runes are with us, 6.0.12 draws near. Stay tuned!