perlMunger,
If you have what you believe to be a common question, chances are it has been asked. Try to use Super Search first to see if someone has already solved your problem. In this case, I offered this solution when it was asked at Adding Unique Elements to Array

Incidently, if you really don't want to use a hash you will be able to do the following in Perl6 which is hiding the search under the covers.

push @array, $value if $value eq none( @array );
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