in reply to Re: Storing part of a regex in a variable
in thread Storing part of a regex in a variable

Correction: it looks like this
(?^x:((?^:(?<identifier> \w+
</code>

(I also forgot x :)

Also, you may find this useful: http://stackoverflow.com/questions/4231382/regular-expression-pattern-not-matching-anywhere-in-string/4234491#4234491