my %hash = qw/John 1 Bob 1 xavier 1 alice 1/;

my @keys = map { (my $x = $_) =~ tr/a-zA-Z/A-Za-z/; $x }
           sort
           map { (my $x = $_) =~ tr/a-zA-Z/A-Za-z/; $x }
           keys %hash;

print "@keys\n";

##</code><code>##

alice xavier Bob John