sub escapeHTML {
    my ( $escape, $whitespace ) = @_;
  return undef unless defined $escape ;
    # make the essential escapes
    $escape =~ s/&/&/g;
    $escape =~ s/"/"/g;
    $escape =~ s/</&lt;/g;
    $escape =~ s/>/&gt;/g;
    # these next optional escapes make text look the same when rendered in HTML
    if ( $whitespace ) {  
        $escape =~ s/\t/    /g;                         # tabs to 4 spaces 
        $escape =~ s/( {2,})/"&nbsp;" x length $1/eg;   # whitespace escapes
        $escape =~  s/\n/<br>\n/g;                      # newlines to <br>
    }
  return $escape;
}