From: ts Date: 2001-06-14T16:56:13+09:00 Subject: [ruby-talk:16463] Re: Opinion sought: parsing non-regular languages >>>>> "R" == Robert Feldt writes: R> /%q(.)(?while count(\1) != count(balancing(\1)))\1/ You are on the road of a P language with this, and there is some madness in it :-))) See (?{}), (??{}), etc and there are *VERY GOOD* reasons for this (from perlre) ------------------------------------------------------------ For reasons of security, this construct is forbidden if the regular expression involves run-time interpolation of variables, unless the perilous C pragma has been used (see L), or the variables contain results of C operator (see L). ------------------------------------------------------------ Guy Decoux