# filset --- expand set at  array (i)  into  set (j),  stop at  delim

   subroutine filset (delim, array, i, set, j, maxset)
   integer i, j, maxset
   character array (ARB), delim, set (maxset)

   character esc
   integer addset, index
   integer junk
   string digits "0123456789"
   string lowalf "abcdefghijklmnopqrstuvwxyz"
   string upalf "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

   for ( ; array (i) ~= delim && array (i) ~= EOS; i += 1)
      if (array (i) == ESCAPE)
         junk = addset (esc (array, i), set, j, maxset)
      else if (array (i) ~= PAT_DASH)
         junk = addset (array (i), set, j, maxset)
      else if (j <= 1 || array (i + 1) == EOS)   # literal -
         junk = addset (PAT_DASH, set, j, maxset)
      else if (index (digits, set (j - 1)) > 0)
         call dodash (digits, array, i, set, j, maxset)
      else if (index (lowalf, set (j - 1)) > 0)
         call dodash (lowalf, array, i, set, j, maxset)
      else if (index (upalf, set (j - 1)) > 0)
         call dodash (upalf, array, i, set, j, maxset)
      else
         junk = addset (PAT_DASH, set, j, maxset)

   return
   end