use strict;
use Data::Dumper;

my $ref = \&bar;
my @arry = foo($ref);
$ref = \&baz;
my $scal = foo($ref);

print Dumper @arry;
print Dumper $scal;

sub foo {
	my $ref = shift;
	my @a = &$ref;
	return wantarray ? @a : $a[0];
}

sub bar { (1..4) }
sub baz { [(1..4)] }