Agreed. Your version can be simplified a little though. 

my @big = qw( a b c d e f g h i a );
my @small = qw(f c d g c);
my %seen;
my @wanted = grep{ !$seen{ $_ }++ } @small, @big;

print "@wanted";
f c d g a b e h i

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^3: Keeping order, no duplicate and the complete keyset by BrowserUk
in thread Keeping order, no duplicate and the complete keyset by Ace128

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