I have two array refs, and I'd like back an array ref of the unique values in the two. My problem is I can't seem to figure out how to return a reference to keys %hash from my function.

Here is what I have: 
sub unique {
  my @refs = @_;
  my %files = ();
  foreach my $ref (@refs) {
    $files{$_}++ foreach (@$ref);
  }
  my @arr = keys %files;
  return \@arr;
}

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I'd like to simplify the last two lines so that I don't need to declare a new array. (I'm using Perl 5.005_03) Any other suggestions for improvement are welcome.

In reply to Return reference to hash keys by miketosh

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