the trap of cross-reference happens like this:
firstly you have an aoa: 
@array1=(
    [1,2,3],
    [4,5,6],
    [7,8,9]
);

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then if you make this: 
$array2[1]=$array1[1]

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and change value in $array1 
$array1[1][0]='something';

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you will get 
print $array2[1][0]; # shows 'something'

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the $array21 is virtually have the same memory space with corresponding value in @array1, because the thing stored in $array1 is actually a reference to the anonymous list 4,5,6. So, what you give to array2 is the same reference, but not the values.

In reply to Re: Updating 1 array affects the other array by llancet
in thread Updating 1 array affects the other array by iphony

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