@array = sort { $a <=> $b } keys %{ { map { $_ => 0 } @array } };

##</code><code>##

use strict;
use warnings;
use Benchmark;

my @testdata;
push @testdata, int rand (100) for 1..500;

sub map_test {
	my @array = @{[ @testdata ]};
	@array = sort { $a <=> $b } keys %{ { map { $_ => 0 } @array } };
	1;
}

sub grep_test {
	my %h;
	my @array = @{[ @testdata ]};
	@array = sort {$a <=> $b} grep { ! $h{$_}++ } @array;
	1;
}

sub do_test {
	my %h;
	my @array = @{[ @testdata ]};
	@array = do { my %h; @h{ @array } = (); sort keys %h };
	1;
}

my $count = 1000;

timethese ( $count, {
	'Map' 	=> \&map_test,
	'Grep' 	=> \&grep_test,
	'Do'	=> \&do_test
} );


##</code><code>##

Benchmark: timing 1000 iterations of Do, Grep, Map...
  Do:  8 wallclock secs ( 7.90 usr +  0.00 sys =  7.90 CPU) @ 126.58/s (n=1000)
  Grep:  9 wallclock secs ( 8.74 usr +  0.00 sys =  8.74 CPU) @ 114.42/s (n=1000)
  Map: 11 wallclock secs (11.26 usr +  0.00 sys = 11.26 CPU) @ 88.81/s (n=1000)