#! /usr/bin/perl -T

use utf8;
use Scalar::Util 'tainted';

use warnings;
use strict;

binmode(STDOUT, ":utf8");

my @chars = qw(x r Ä a L ö K f Ü r T b u);

my @sorted;
if (shift) {
    use locale;
    @sorted = sort @chars;
} else {
    @sorted = sort @chars;
}

my $s = "hubert";
my ($res) = $s =~ /(\w)/;
die "res is tainted!\n" if tainted($res);

print join (' ', @sorted), "\n";