I use the following (from perlfaq4): 

my %seen;
my @mergedkeys = grep !$seen{$_}++, @array1, @array2;

[download]

It's a bit of a doozie to understand, but it's just one of those patterns you keep seeing and you memorise.

Bonus: it preserves order.

In reply to Re: Merge arrays - seeking slicker approach by ikegami
in thread Merge arrays - seeking slicker approach by puterboy

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