Another way (stealing james2vegas's die message): 
use warnings;
use strict;
use Getopt::Long;

my $_debug = 1; # or whatever default you want it to be
GetOptions('d=i' => \$_debug) or die("Invalid commmand line options.")
+;

die "Invalid Debug Level ($_debug)" if $_debug<1 or $_debug>4;

print "\$_debug = $_debug\n";

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In reply to Re: Range in Getopt by toolic
in thread Range in Getopt by Ammu

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