The ugly way is to do something like: 
$num =~ m{
  \A
  5
  (?:
    2 (?: 7[89] | [89][0-9] )
    |
    3 (?: [0-8][0-9] | 9[01] )
  )
  \z
}x;

[download]
You can see why I say it's ugly. But it works. I think I could even come up with a range-to-regex converter, for people in such a sad predicament. ;)

Originally posted as a Categorized Answer.

In reply to Re: How do I match a number range? by japhy
in thread How do I match a number range? by Anonymous Monk

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