Natools

   begin
      for I in Result'Range loop
         if Result (I) = Plus then
            Result (I) := Digit_62;
         elsif Result (I) = Slash then
            Result (I) := Digit_63;
         elsif Result (I) = Base64_Filler then
            for J in I + 1 .. Result'Last loop
               pragma Assert (Result (J) = Base64_Filler);
            end loop;
            Last := I - 1;
            exit;
         end if;
      end loop;

      return Result (Result'First .. Last);
   end Encode_Base64;