What version of perl are you using? It works as posted for me running perl 5.6.1 on Redhat linux 8.
From perlre:
(??{ code })
WARNING: This extended regular expression feature is considered hi
+ghly experimental, and may be changed or deleted without notice. A si
+mplified version of the syntax may be introduced for commonly used id
+ioms.
This is a ``postponed'' regular subexpression. The code is evaluat
+ed at run time, at the moment this subexpression may match. The resul
+t of evaluation is considered as a regular expression and matched as
+if it were inserted instead of this construct.
The code is not interpolated. As before, the rules to determine wh
+ere the code ends are currently somewhat convoluted.
The following pattern matches a parenthesized group:
$re = qr{
\(
(?:
(?> [^()]+ ) # Non-parens without backtracking
|
(??{ $re }) # Group with matching parens
)*
\)
}x;
They say that time changes things, but you actually have to change them yourself. Andy Warhol
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Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
<u> <ul>
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Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
intervention).
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Want more info? How to link
or How to display code and escape characters
are good places to start.
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