package Adder;

sub new{
  my ($class) = @_;
  my $self = {sum => 0};
  bless $self,$class;
  return $self;
}

sub connectSum{
  my ($self,$var) = @_;
  $self->{SumVar} = $var;
}

sub refresh{
  my ($self,$old,$new) = @_;
  $self->{sum} += ($new - $old);
  $self->{SumVar}->setValueSqrtVar($self->{sum});
}

1;