Here is another, perhaps less pretty, way to do it: 
substr($string, index($string, '<tag>'), rindex($string, '</tag>')) =~
+ s/\n(?!$)/<br>/g;

[download]

Update: I was using the return value of rindex as the length parameter to substr. Oops! Here is a correct, albeit even less pretty, version of the above: 
substr($string, index($string, '<tag>'), rindex($string, '</tag>') - i
+ndex($string, '<tag>')) =~ s/\n/<br>/g;

[download]
Yech! It gets rid of the negative look-ahead assertion (since the length is corrected), but it's ugly, and duplicates some function calls. A better version (but uses temp vars) is: 
my $st = index($string, '<tag>');
my $en = rindex($string, '</tag>') - $st;

substr($string, $st, $en) =~ s/\n/<br>/g;

[download]
Much better. Though I'm still not sure if it's an improvement over the other suggestions above.

--sacked

In reply to (sacked: substr) Re: Editting Part of Regex by sacked
in thread Editting Part of Regex by mt2k

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