A simple hash can be made to maintain order and since zero extra lines are used in the foregoing example (just a couple of inline additions), the overheads of interfacing to a module seem way too much. One should not reach for the nearest module the minute the going gets the slightest bit non-trivial - rather later in the thought process perhaps - it also seems appropriate to encourage people to think rather than be mentally lazy.
my %h = ();
while (<$fh>) {
    $h{ $_ } ||= $.;
}
close $fh;
print sort { $h{a} <=> $h{b} } keys %h;

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-M

Free your mind

In reply to Re^2: To Hash or to Array--Uniqueness is the question. by Moron
in thread To Hash or to Array--Uniqueness is the question. by eff_i_g

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