Hello Monks,

I have a problem with ref array which i have spent sometimes debugging it. I fixed it but still don't understand how this can happen. Below is a shorten version of the code:

my $ra = [ 'A', 'B', 'C' ];

print STDERR '1. ra = ' . Dumper( $ra );

test_ra( $ra );

print STDERR '2. ra = ' . Dumper( $ra );

exit;


sub test_ra
{
    my $data = shift;
    foreach my $item ( @{ $data } )
    {
        $item = 'Z';
    }
}

[download]
After running the code: 
1. ra = [ 'A','B','C' ]
2. ra = [ 'Z','Z','Z' ]

[download]

Apparently assigning some other value to $item modifies my ref array. This is something i'm not expecting. Off course when i copy the content of the array to another one (my @dup_array = @{$data}) and use it, the problem will disappeared.

Maybe i've overlooked something, but hopefully you can shine some light on the darkness.

TIA

PS: i'm using v5.8.8

In reply to ref array being modified unexpectively by duyet

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