range$ = " 0,  1,  2,  4,  6,  7,  8, 11, 12, 14, " + \
      \        "15, 16, 17, 18, 19, 20, 21, 22, 23, 24, " + \
      \        "25, 27, 28, 29, 30, 31, 32, 33, 35, 36, " + \
      \        "37, 38, 39"
      PRINT FNrangeextract(range$)
      END

      DEF FNrangeextract(r$)
      LOCAL f%, i%, r%, t%, t$
      f% = VAL(r$)
      REPEAT
        i% = INSTR(r$, ",", i%+1)
        t% = VALMID$(r$, i%+1)
        IF t% = f% + r% + 1 THEN
          r% += 1
        ELSE
          CASE r% OF
            WHEN 0: t$ += STR$(f%) + ","
            WHEN 1: t$ += STR$(f%) + "," + STR$(f% + r%) + ","
            OTHERWISE: t$ += STR$(f%) + "-" + STR$(f% + r%) + ","
          ENDCASE
          r% = 0
          f% = t%
        ENDIF
      UNTIL i% = 0
      = LEFT$(t$)