#! perl -slw
use strict;

my $foo;

sub test{ print "@$foo" }

for my $ref ( [ 1,2,3 ], [ 4,5,6 ] ) {
	$foo = $ref;
	test();
}
__END__
P:\test>test3
1 2 3
4 5 6

##</code><code>##

#! perl -slw
use strict;

my $foo;

sub test{ print "@$foo" }

for $foo ( [ 1,2,3 ], [ 4,5,6 ] ) {
	test();
}
__END__
P:\test>test3
Can't use an undefined value as an ARRAY reference at P:\test\test3.pl line 6.