#!/usr/bin/perl

use strict;
use warnings;

my @list = (1, 2, 1);
print join ',', sort (unique (@list));
print join ',', sort (unique(@list));

sub unique { 
  my %new = ();
  return grep (!$new{$_}++, @_);
}

##</code><code>##

Chromium:~ lexicon$ perl -l little2.pl 
Unquoted string "unique" may clash with future reserved word at little2.pl line 7.
1,2,1
1,2      

##</code><code>##

Chromium:~ lexicon$ perl -l -MO=Deparse little2.pl 
Unquoted string "unique" may clash with future reserved word at little2.pl line 7.
BEGIN { $/ = "\n"; $\ = "\n"; }
use warnings;
use strict 'refs';
my(@list) = (1, 2, 1);
print join(',', (sort unique @list));
print join(',', sort(unique(@list)));
sub unique {
    use warnings;
    use strict 'refs';
    my %new;
    return grep((!$new{$_}++), @_);
}
little2.pl syntax OK