#!/usr/bin/perl6
my regex paren_any { '(' ~ ')' [ <-[()]>+ || <&paren_any> ]* }
say "Extract (a(b)c) and ((d)f(g))" ~~ m:g/<&paren_any>/;
say "Extract (a(b)c) and ((d)f(g))" ~~ m:ov:g/<&paren_any>/;