The plain old C way: 
#!perl

use strict;
use warnings;

sub contains_alpha($) {
   my ($ord_a, $ord_z, $ord_A, $ord_Z) = map ord, qw/a z A Z/;
   for (split //, $_[0]) {
      $_ = ord $_;
      return 1
         if ($ord_a <= $_ and $_ <= $ord_z) || ($ord_A <= $_ and $_ <=
+ $ord_Z);
   }
   return 0;
}

for (<DATA>) {
   chomp;
   print "'$_' " . (contains_alpha $_ ? 'contains' : 'does not contain
+')
       . " standard alphabet characters\n";
}
__DATA__
Hi
123456789o
1234567890
xAFCE3
xAFCEA
... --- ...
.s. -o- .s.

[download]
Not really creative, though...
CombatSquirrel.
Entropy is the tendency of everything going to hell.

In reply to Re: Challenge - Creative Way To Detect Alpha Characters by CombatSquirrel
in thread Challenge - Creative Way To Detect Alpha Characters by Limbic~Region

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