With all due respect to jlistf, there were a couple of problems with his solution. Here's one that's easy to understand: 
if ($filename =~ /^[A-Z]{5}/) {
    ($section_title = $filename) =~ s!:!:</B>\n<BR><BR>!;
    $filename = "";
}

[download]
For $filename, we're just testing for the first five letters, so the {5,} syntax just makes the regex engine do more work.

For the actual substitution, the slash in </B> needs to be escaped unless we choose different delimiters like I have above.

Also, we can't do 

$section_title = ($filename =~ s/?[:]./':</B>\n< BR>< B>\n');

[download]
because the substitution returns a true/false value and if successful, $section_title receives a value of 1. The assignment to $section_title needs to be on a different line or assigned to as above (that's from a suggestion by KM).

Cheers,
Ovid

Update: Cleaned up the code in response to KM's point.

In reply to (Ovid) RE: Regular Expression Help by Ovid
in thread Regular Expression Help by Anonymous Monk

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