#!/usr/bin/perl
use strict;
use warnings;
use Mypackage;

my $object = new Mypackage();
$object->setValue(100);
print $object->getValue() . "\n"; # retrievable from any script

__END__

$ perl main.pl
100

##</code><code>##

package Mypackage;
use strict;
use warnings;

sub new {
    my $class = shift;
    my $self = {
	_value => shift,
    };
    bless $self, $class;
    return $self;
}

sub getValue {
    my( $self ) = @_;
    return $self->{_value};
}

sub setValue {
    my ( $self, $value ) = @_;
    $self->{_value} = $value if defined($value);
    # return $self->{_value};
}

1;

##</code><code>##

#!/usr/bin/perl
use strict;
use warnings;
use Mypackage;

my $object = new Mypackage(100);
print $object->getValue() . "\n";
$object->setValue(200);
print $object->getValue() . "\n";

__END__

$ perl main.pl
100
200