Instead of trying to do everything with a single regular expression, consider breaking it up into two. 

$str =~ s/\[id=(\d+)\]/<a href='...$1'>/g;
$str =~ s/\[\/id\]/<\/a>/g;
print $str;

[download]

This will deal more gracefully with links that span multiple lines (which often happens when people write in a auto-wrapping editor.)

In reply to Re: Re: Monks' Expression by eg
in thread Monks' Expression by sinan

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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