lpeg pattern repetition

[Nick Gammon <nick@...>]

Hi,

I have been trying out lpeg, and am wondering if there is an easy way  
of representing the notion of something like this:

  I see 4567 cattle

... where the number is a 4 to 6-digit number.

In PCRE I would write it like this:

  I see [0-9]{4,6} cattle

The best I could come up with in lpeg is:

  require "lpeg"

  digits = lpeg.R "09"
  patt = lpeg.P "I see " * digits * digits * digits * digits *  
digits^-2 * " cattle"

  print (lpeg.match (patt, "I see 4567 cattle"))  --> 18


This requires the explicit repetition of the digits four times,  
followed by no more than 2 extra ones.

Is there an easier or less wordy way of doing this? I know I can use a  
"for" loop to concatenate "digits", but apart from that?

- Nick Gammon