Won't \w match any letter, number, or underscore?
if ($str =~ m/\d[A-Z]\d+/) {
  print "Ok!\n";
} else {
  print "Invalid format! Must be: [digit][letter][digit][digit] ... \n
+";
}

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Joshua

In reply to Re: Re: Comparing lower to upper case by joshua
in thread Comparing lower to upper case by bobothesmart

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