One way 

perl> @big = qw(a b c d e f g h i);;
perl> @small = qw(f c d g);;
perl> undef @found{ @small };;

perl> @wanted = ( @small, grep{ !exists $found{ $_ } } @big );;

perl> 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: 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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