use warnings;
use strict;
use 5.012;
use Smart::Comments '###';

my @foo;

sub ding {
	@{$_[0]} || ();
}

my @a = qw(apple banana pear grapes);
my @b = qw(lettuce onions);
my @c = qw(popcorn ice-cream);

@foo = ding(\@a, \@b, \@c);

### @foo

#--- Result:
#### @foo: [
####         4
####       ]