##
DB<40> %h = ( '*'=>'b', '/' => 'i' , '_' => 'u' )
DB<59> sub tf { s{ $pre ([_*/]) (.*?) \2 $post}{$1<$h{$2}>$3$h{$2}>$4}xg }
DB<62> $pre = qr/(^|\s|>)/
DB<63> $post = qr/($|\s|<)/
DB<65> $wiki='_*one /two/*_ _*three /four/*_ _*five /six/*_'
##
##
DB<90> sub tf { s{ $pre ([_*/]) (.*?) \2 (?=$post)}{$1<$h{$2}>$3$h{$2}>}xg }