Note that this is slightly broken as is. To be entirely correct, you have to say 
my (%seen, $seen_undef);
my @uniq = grep defined() ? !$seen{$_}++ : !$seen_undef++, @list;

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Of course, if you're fiddling with objects which cannot be compared for equity by stringification, it is still broken.

Makeshifts last the longest.

In reply to Re^2: Perl Idioms Explained - keys %{{map{$_=>1}@list}} by Aristotle
in thread Perl Idioms Explained - keys %{{map{$_=>1}@list}} by broquaint

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