As I noted in a previous post 175510 I am writing a simple Set object. However... I've hit a problem. Code is below then I explain:

package Abh::SimpleSet;

sub new {
  my $self = {};
  bless $self;
  return $self; 
}

sub add {
  my ($self, $item) = @_;
  $self{$item} = undef; 
}

sub remove {
  my ($self, $item) = @_;
  delete($self{$item});
}

sub contains {
  my ($self, $item) = @_;
  return exists($self{$item});  
}

sub to_string {
  my $self = shift;
  return $class, "(" . join (", ", keys %self) . ")";
}

sub union {
  my ($self, $otherSet) = @_;
  foreach $key (keys %otherSet) {
    $self{$key} = undef;
  }  
}

# Must return true
1;

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When I run the following using the above module...

use Abh::SimpleSet;

$set1 = Abh::SimpleSet->new();
$set2 = Abh::SimpleSet->new();

$set1->add("a");
$set1->add("b");
$set1->add("c");
print "Set 1: " . $set1->to_string() . "\n";

$set2->add("d");
$set2->add("e");
$set2->add("f");
print "Set 2: " . $set2->to_string() . "\n";

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... I get this output.

Set 1: (a, b, c)
Set 2: (e, f, a, b, c, d)

[download]

I was expecting set 2 to contain just (d, e, f)... can someone help? I'm sure its a simple problem, but I checked the various OO tutorials and perlobj docs to no avail :(

Thanks,

____________
Arun

In reply to Problem with My New Perl Object by arunhorne

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