this will fail under certain circumstances. for instance:

my @non_unique = qw/carpet car pet/; # fails on 'car' and 'pet'
my @non_unique = ("bob and sue","bob"); # fails on space seperated wor
+ds
[download]

i could go on, but i think you get the point. if you don't want to alter the order of the items, and you want to use some perl 5 magic, you can use a pseudo-hash. before i go on, i must say that pseudo-hashes are considered a failed experiment, and will most likely not be suppored in Perl 6. the example below is simply to provide some enlightenment as to how they work (which i like.)

check Returning A Pseudo-Hash in Array Context for a little discussion on pseudo-hashes
for an offsite explanation on pseudo-hashes, find the link on japhy's homepage, http://www.crusoe.net/~jeffp/
also, check the documentation: fields and the Pseudo-hashes section of perlref

#!/usr/local/bin/perl -w
use strict;
$|++;

# array of non-unique words
my @non_unique = ('bob and sue', 'bobcat', 'carpet', 'bob', 'car', 'ca
+rpet');

# create empty pseudo-hash
#   hash key is unique word, hash value is array index, array value is
+ count
my $ph = [{},]; 

for(@non_unique) 
{
    if(exists $ph->{$_})     # if word already in hash,
    {
        $ph->{$_}++;         #   increment word count
    }
    else                     # else
    {
        $ph->[0]{$_} = @$ph; #   set hash key to last array index (end
+ of array)
        $ph->{$_}++;         #   increment word count to 1
#         or in one line... (a little obfuscated)
#         $ph->[$ph->[0]{$_} = @$ph]++;
    }
#     or on one line... (a little more obfuscated - not recommended)
#     exists $ph->{$_} ? $ph->{$_}++ : $ph->[$ph->[0]{$_} = @$ph]++;
}
# or on one line... (even more obfuscated - really not recommended)
# map{exists$ph->{$_}?$ph->{$_}++:$ph->[$ph->[0]{$_}=@$ph]++}@non_uniq
+ue;

# array of unique words, same order as non-unique words
#   (the extraction procedure looks a little messy)
#   it says, for the keys of the hash section of the pseudo-hash,
#     sort by the value, ascending
my @unique = sort { $ph->[0]{$a} <=> $ph->[0]{$b} } keys %{$ph->[0]};

# pretty formatted output of unique array and word count
format SortedWordsAndCountHeader =
Words               Count
.
format SortedWordsAndCount =
@<<<<<<<<<<<<<<<<<< @>>>>
$_,                 $ph->{$_}
.

$^ = "SortedWordsAndCountHeader";
$~ = "SortedWordsAndCount";
write for @unique;
[download]

this produces the output

Words               Count
bob and sue             1
bobcat                  1
carpet                  2
bob                     1
car                     1
[download]

~Particle

---

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