{
   for ($text) {  # Alias $_ to $text.
      /\G ``   (.*?) ``   /gcsx && do { print($1         ); redo };
      /\G \*\* (.*?) \*\* /gcsx && do { print("<b>$1</b>"); redo };

      /\G
         (
            .            # Catchall.

            (?:          # These four lines are optional.
               (?!``)    # They are here to speed things up
               (?!\*\*)  # by avoiding calling print for
            .)*          # single characters.
         )
      /gcsx && do { print($1); redo };
   }
}