Here's a way that uses map in a non-void context: 
use Data::Dumper;

my %counts;
my @array = qw (aa bb cc aa aa cc cc dd aa aa);
%counts = map {$_ => ++$counts{$_} } @array;
print Dumper(\%counts);

[download]
Here's another: 
my %counts = map {
    my $n;
    do { $n = (($last=$_) ... ($last ne $_)) } while $n =~ /E0$/;
    ($last => $n);
} sort @array;

[download]
Why they work is left as an exercise for the reader. ;-)
Caution: Contents may have been coded under pressure.

In reply to Re^2: Counting unique elements in an array by Roy Johnson
in thread Counting unique elements in an array by Anonymous Monk

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