#!/usr/bin/perl -w

use strict;

if ($ARGV[0] !~ /(.).*(??{"[^$1-z]"})/ix)
{
  print "alpha\n";
}
else
{
  print "non-alpha\n";
}
__END__
[sgifford@sglaptop sgifford]$ perl /tmp/t4 abcxz
alpha
[sgifford@sglaptop sgifford]$ perl /tmp/t4 abcda
non-alpha
[sgifford@sglaptop sgifford]$ perl /tmp/t4 aaaaaaab
alpha
[sgifford@sglaptop sgifford]$ perl /tmp/t4 aaaaaaabcccccccz
alpha
[sgifford@sglaptop sgifford]$ perl /tmp/t4 aaaaaaabcccccdccz
non-alpha
[sgifford@sglaptop sgifford]$ perl /tmp/t4 aaaaaaaaaaaaa    
alpha
[sgifford@sglaptop sgifford]$ perl /tmp/t4 abcdefghijklmnopqrstuvwxyz
alpha