Folks,

I am having a problem which I have so far failed to solve myself mainly, I suspect, because I don't understand the problem well enough!

I have a package with an object TESTOBJ which includes a name and, as one of the elements, an array (__mpp). When I use this object I want to be able to store up to ten values in __mpp.

In my application I am trying to build an array of TESTOBJ using the constructor to create each object. The problem is that I seem only to have one array (__mpp) shared between all my objects!

In the sample code below I create two TESTOBJ and populate them but when I set __mpp in the second object it affects __mpp in the first. Why is this ?

use TESTOBJ;
my @res = ();

my $t = new TESTOBJ;
$t->name("first");
$t->mpp0(111);
$res[0] = $t;
printf "Dump \$res[0]:  name '%s' mpp '%d'\n", 
                     $res[0]->name(), $res[0]->mpp0();

$t = new TESTOBJ;
$t->name("second");
$t->mpp0(222);
$res[1] = $t;
printf "Dump \$res[0]:  name '%s' mpp '%d'\n", 
                     $res[0]->name(), $res[0]->mpp0();
printf "Dump \$res[1]:  name '%s' mpp '%d'\n", 
                     $res[1]->name(), $res[1]->mpp0();

[download]

And TESTOBJ.pm contains

package TESTOBJ;

my %fields = (
    __name   => undef,
    __mpp    => [ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 ]
);

sub new {
    my $that  = shift;
    my $class = ref($that) || $that;
    my $self  = { %fields };
    bless $self, $class;
    return $self;
} 

sub name {
    my $obj = shift;
    @_ ? $obj->{__name} = shift    # modify attribute
       : $obj->{__name};           # retrieve attribute
}

sub mpp0 {
    my $obj = shift;
    @_ ? $obj->{__mpp}[0] = shift  # modify attribute
       : $obj->{__mpp}[0];         # retrieve attribute
}

[download]

Regards, Gavin

In reply to Anonymous array in object by GGGav

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