If you don't pass a reference, the array is flattened, and passed out as a simple list - not something you want in this case.
Er, wha? This is a perfectly valid case to pass a list back and forth. Since the code is only dealing with a single array this is not an issue, it would be an issue however if multiple arrays were being passed about e.g 
sub f { print "got: ", @_, $/ }

my @a = qw( one two three );
my @b = qw( four five six );

## @a & @b will be flattened into a single list
f(@a, @b);

## pass references to keep array integrity
f(\@a, \@b);

## only @a is passed, so only @a is received
f(@a);

__output__

got: onetwothreefourfivesix
got: ARRAY(0x8107e50)ARRAY(0x8107f34)
got: onetwothree

[download]

HTH

_________
broquaint

In reply to Re: Re: Passing Array of Arrays by broquaint
in thread Passing Array of Arrays by marctwo

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