Surely the code can be simplified by using a s///g at the top level instead of looping? 
$source =~ s/(\[link title:(.*?)\](.*?)\[\/link])/<a href='$3'>$2<\/a>
+/gi;

[download]
The obvious limitation over the original solution is that it doesn't allow one to loop, but perhaps this would work? 
while ($source =~ s/\G(\[link title:(.*?)\](.*?)\[\/link])/<a href='$3
+'>$2<\/a>/i) {
  print "complete: $1\ntitle: $2\nurl: $3\n";
}

[download]

--
integral, resident of freenode's #perl

In reply to Re: replacing variable in regex - probs with special chars? by integral
in thread replacing variable in regex - probs with special chars? by Emanuel

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